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linux/fs/fuse/file.c

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[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: style fixes Fix coding style errors reported by checkpatch and others. Uptdate copyright date to 2008. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:54 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
Detach sched.h from mm.h First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-21 01:22:52 +04:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: fix ioctl when server is 32bit If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: mark pages accessed when written to As fuse does not use the page cache library functions when userspace writes to a file, it did not benefit from 'c8236db mm: mark page accessed before we write_end()' that made sure pages are properly marked accessed when written to. Signed-off-by: Johannes Weiner <jweiner@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-07-25 22:35:35 +02:00
fuse: truncate pagecache range on hole punch fuse supports hole punch via the fallocate() FALLOC_FL_PUNCH_HOLE interface. When a hole punch is passed through, the page cache is not cleared and thus allows reading stale data from the cache. This is easily demonstrable (using FOPEN_KEEP_CACHE) by reading a smallish random data file into cache, punching a hole and creating a copy of the file. Drop caches or remount and observe that the original file no longer matches the file copied after the hole punch. The original file contains a zeroed range and the latter file contains stale data. Protect against writepage requests in progress and punch out the associated page cache range after a successful client fs hole punch. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 09:30:32 -04:00
fs: move struct kiocb to fs.h struct kiocb now is a generic I/O container, so move it to fs.h. Also do a #include diet for aio.h while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 08:58:50 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 01:56:42 -08:00
[PATCH] fuse: more flexible caching Make data caching behavior selectable on a per-open basis instead of per-mount. Compatibility for the old mount options 'kernel_cache' and 'direct_io' is retained in the userspace library (version 2.4.0-pre1 or later). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:37 -07:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: add atomic open+truncate support This patch allows fuse filesystems to implement open(..., O_TRUNC) as a single request, instead of separate truncate and open requests. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: add file kernel handle The file handle, fuse_file->fh, is opaque value supplied by userland FUSE server and uniqueness is not guaranteed. Add file kernel handle, fuse_file->kh, which is allocated by the kernel on file allocation and guaranteed to be unique. This will be used by poll to match notification to the respective file but can be used for other purposes where unique file handle is necessary. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: add members to struct fuse_file Add new members ->fc and ->nodeid to struct fuse_file. This will aid in converting functions for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: general infrastructure for pages[] of variable size The patch removes inline array of FUSE_MAX_PAGES_PER_REQ page pointers from fuse_req. Instead of that, req->pages may now point either to small inline array or to an array allocated dynamically. This essentially means that all callers of fuse_request_alloc[_nofs] should pass the number of pages needed explicitly. The patch doesn't make any logic changes. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:07 +04:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
[PATCH] fuse: ensure FLUSH reaches userspace All POSIX locks owned by the current task are removed on close(). If the FLUSH request resulting initiated by close() fails to reach userspace, there might be locks remaining, which cannot be removed. The only reason it could fail, is if allocating the request fails. In this case use the request reserved for RELEASE, or if that is currently used by another FLUSH, wait for it to become available. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
fuse: cleanup in release Move dput/mntput pair from request_end() to fuse_release_end(), because there's no other place they are used. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:04 -07:00
fuse: hold inode instead of path after release path_put() in release could trigger a DESTROY request in fuseblk. The possible deadlock was worked around by doing the path_put() with schedule_work(). This complexity isn't needed if we just hold the inode instead of the path. Since we now flush all requests before destroying the super block we can be sure that all held inodes will be dropped. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:04 +01:00
fuse: cleanup in release Move dput/mntput pair from request_end() to fuse_release_end(), because there's no other place they are used. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:04 -07:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: support clients that don't implement 'open' open/release operations require userspace transitions to keep track of the open count and to perform any FS-specific setup. However, for some purely read-only FSs which don't need to perform any setup at open/release time, we can avoid the performance overhead of calling into userspace for open/release calls. This patch adds the necessary support to the fuse kernel modules to prevent open/release operations from hitting in userspace. When the client returns ENOSYS, we avoid sending the subsequent release to userspace, and also remember this so that future opens also don't trigger a userspace operation. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 16:05:52 +01:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: hold inode instead of path after release path_put() in release could trigger a DESTROY request in fuseblk. The possible deadlock was worked around by doing the path_put() with schedule_work(). This complexity isn't needed if we just hold the inode instead of the path. Since we now flush all requests before destroying the super block we can be sure that all held inodes will be dropped. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:04 +01:00
fuse: support clients that don't implement 'open' open/release operations require userspace transitions to keep track of the open count and to perform any FS-specific setup. However, for some purely read-only FSs which don't need to perform any setup at open/release time, we can avoid the performance overhead of calling into userspace for open/release calls. This patch adds the necessary support to the fuse kernel modules to prevent open/release operations from hitting in userspace. When the client returns ENOSYS, we avoid sending the subsequent release to userspace, and also remember this so that future opens also don't trigger a userspace operation. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 16:05:52 +01:00
fuse: add missing FR_FORCE commit 2e38bea99a80eab408adee27f873a188d57b76cb upstream. fuse_file_put() was missing the "force" flag for the RELEASE request when sending synchronously (fuseblk). If this flag is not set, then a sync request may be interrupted before it is dequeued by the userspace filesystem. In this case the OPEN won't be balanced with a RELEASE. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 5a18ec176c93 ("fuse: fix hang of single threaded fuseblk filesystem") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-22 20:08:25 +01:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
fuse: hold inode instead of path after release path_put() in release could trigger a DESTROY request in fuseblk. The possible deadlock was worked around by doing the path_put() with schedule_work(). This complexity isn't needed if we just hold the inode instead of the path. Since we now flush all requests before destroying the super block we can be sure that all held inodes will be dropped. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:04 +01:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: support clients that don't implement 'open' open/release operations require userspace transitions to keep track of the open count and to perform any FS-specific setup. However, for some purely read-only FSs which don't need to perform any setup at open/release time, we can avoid the performance overhead of calling into userspace for open/release calls. This patch adds the necessary support to the fuse kernel modules to prevent open/release operations from hitting in userspace. When the client returns ENOSYS, we avoid sending the subsequent release to userspace, and also remember this so that future opens also don't trigger a userspace operation. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 16:05:52 +01:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: support clients that don't implement 'open' open/release operations require userspace transitions to keep track of the open count and to perform any FS-specific setup. However, for some purely read-only FSs which don't need to perform any setup at open/release time, we can avoid the performance overhead of calling into userspace for open/release calls. This patch adds the necessary support to the fuse kernel modules to prevent open/release operations from hitting in userspace. When the client returns ENOSYS, we avoid sending the subsequent release to userspace, and also remember this so that future opens also don't trigger a userspace operation. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 16:05:52 +01:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: Linking file to inode helper When writeback is ON every writeable file should be in per-inode write list, not only mmap-ed ones. Thus introduce a helper for this linkage. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:04 +04:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: fix attributes after open(O_TRUNC) The attribute cache for a file was not being cleared when a file is opened with O_TRUNC. If the filesystem's open operation truncates the file ("atomic_o_trunc" feature flag is set) then the kernel should invalidate the cached st_mtime and st_ctime attributes. Also i_size should be explicitly be set to zero as it is used sometimes without refreshing the cache. Signed-off-by: Ken Sumrall <ksumrall@android.com> Cc: Anfei <anfei.zhou@gmail.com> Cc: "Anand V. Avati" <avati@gluster.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-24 12:57:00 -08:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: fix page invalidation Other than truncate, there are two cases, when fuse tries to get rid of cached pages: a) in open, if KEEP_CACHE flag is not set b) in getattr, if file size changed spontaneously Until now invalidate_mapping_pages() were used, which didn't get rid of mapped pages. This is wrong, and becomes more wrong as dirty pages are introduced. So instead properly invalidate all pages with invalidate_inode_pages2(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:01 -07:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: implement nonseekable open Let the client request nonseekable open using FOPEN_NONSEEKABLE and call nonseekable_open() on the file if requested. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-10-16 16:08:57 +02:00
fuse: fix attributes after open(O_TRUNC) The attribute cache for a file was not being cleared when a file is opened with O_TRUNC. If the filesystem's open operation truncates the file ("atomic_o_trunc" feature flag is set) then the kernel should invalidate the cached st_mtime and st_ctime attributes. Also i_size should be explicitly be set to zero as it is used sometimes without refreshing the cache. Signed-off-by: Ken Sumrall <ksumrall@android.com> Cc: Anfei <anfei.zhou@gmail.com> Cc: "Anand V. Avati" <avati@gluster.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-24 12:57:00 -08:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
fuse: fix attributes after open(O_TRUNC) The attribute cache for a file was not being cleared when a file is opened with O_TRUNC. If the filesystem's open operation truncates the file ("atomic_o_trunc" feature flag is set) then the kernel should invalidate the cached st_mtime and st_ctime attributes. Also i_size should be explicitly be set to zero as it is used sometimes without refreshing the cache. Signed-off-by: Ken Sumrall <ksumrall@android.com> Cc: Anfei <anfei.zhou@gmail.com> Cc: "Anand V. Avati" <avati@gluster.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-24 12:57:00 -08:00
fuse: Turn writeback cache on Introduce a bit kernel and userspace exchange between each-other on the init stage and turn writeback on if the userspace want this and mount option 'allow_wbcache' is present (controlled by fusermount). Also add each writable file into per-inode write list and call the generic_file_aio_write to make use of the Linux page cache engine. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:18 +04:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: add file kernel handle The file handle, fuse_file->fh, is opaque value supplied by userland FUSE server and uniqueness is not guaranteed. Add file kernel handle, fuse_file->kh, which is allocated by the kernel on file allocation and guaranteed to be unique. This will be used by poll to match notification to the respective file but can be used for other purposes where unique file handle is necessary. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: update mtime on open(O_TRUNC) in atomic_o_trunc mode In case of fc->atomic_o_trunc is set, fuse does nothing in fuse_do_setattr() while handling open(O_TRUNC). Hence, i_mtime must be updated explicitly in fuse_finish_open(). The patch also adds extra locking encompassing open(O_TRUNC) operation to avoid races between the truncation and updating i_mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
[PATCH] fuse: add asynchronous request support Add possibility for requests to run asynchronously and call an 'end' callback when finished. With this, the special handling of the INIT and RELEASE requests can be cleaned up too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:42 -08:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
[PATCH] fuse: ensure FLUSH reaches userspace All POSIX locks owned by the current task are removed on close(). If the FLUSH request resulting initiated by close() fails to reach userspace, there might be locks remaining, which cannot be removed. The only reason it could fail, is if allocating the request fails. In this case use the request reserved for RELEASE, or if that is currently used by another FLUSH, wait for it to become available. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: save space in struct fuse_req Move the fields 'dentry' and 'vfsmount' into the request specific union, since these are only used for the RELEASE request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 01:38:39 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: wakeup pollers on connection release/abort If a fuse dev connection is broken, wake up any processes that are blocking, in a poll system call, on one of the files in the now defunct filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-03-01 16:43:52 -08:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
[PATCH] fuse: no backgrounding on interrupt Don't put requests into the background when a fatal interrupt occurs while the request is in userspace. This removes a major wart from the implementation. Backgrounding of requests was introduced to allow breaking of deadlocks. However now the same can be achieved by aborting the filesystem through the 'abort' sysfs attribute. This is a change in the interface, but should not cause problems, since these kinds of deadlocks never happen during normal operation. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:50 -07:00
fuse: clean up args in fuse_finish_open() and fuse_release_fill() Move setting ff->fh, ff->nodeid and file->private_data outside fuse_finish_open(). Add ->open_flags member to struct fuse_file. This simplifies the argument passing to fuse_finish_open() and fuse_release_fill(), and paves the way for creating an open helper that doesn't need an inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
[PATCH] FUSE: atomic create+open This patch adds an atomic create+open operation. This does not yet work if the file type changes between lookup and create+open, but solves the permission checking problems for the separte create and open methods. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 00:59:51 -08:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: fix flock Commit a9ff4f87 "fuse: support BSD locking semantics" overlooked a number of issues with supporing flock locks over existing POSIX locking infrastructure: - it's not backward compatible, passing flock(2) calls to userspace unconditionally (if userspace sets FUSE_POSIX_LOCKS) - it doesn't cater for the fact that flock locks are automatically unlocked on file release - it doesn't take into account the fact that flock exclusive locks (write locks) don't need an fd opened for write. The last one invalidates the original premise of the patch that flock locks can be emulated with POSIX locks. This patch fixes the first two issues. The last one needs to be fixed in userspace if the filesystem assumed that a write lock will happen only on a file operned for write (as in the case of the current fuse library). Reported-by: Sebastian Pipping <webmaster@hartwork.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
fuse: hold inode instead of path after release path_put() in release could trigger a DESTROY request in fuseblk. The possible deadlock was worked around by doing the path_put() with schedule_work(). This complexity isn't needed if we just hold the inode instead of the path. Since we now flush all requests before destroying the super block we can be sure that all held inodes will be dropped. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:04 +01:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
fuse: misc cleanups * fuse_file_alloc() was structured in weird way. The success path was split between else block and code following the block. Restructure the code such that it's easier to read and modify. * Unindent success path of fuse_release_common() to ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:49 +09:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
fuse: create fuse_do_open() helper for CUSE Create a helper for sending an OPEN request that doesn't need a struct inode pointer. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
fuse: Flush files on wb close Any write request requires a file handle to report to the userspace. Thus when we close a file (and free the fuse_file with this info) we have to flush all the outstanding dirty pages. filemap_write_and_wait() is enough because every page under fuse writeback is accounted in ff->count. This delays actual close until all fuse wb is completed. In case of "write cache" turned off, the flush is ensured by fuse_vma_close(). Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:19:06 +04:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: don't use inode in fuse_sync_release() Make fuse_sync_release() a generic helper function that doesn't need a struct inode pointer. This makes it suitable for use by CUSE. Change return value of fuse_release_common() from int to void. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
[PATCH] fuse: scramble lock owner ID VFS uses current->files pointer as lock owner ID, and it wouldn't be prudent to expose this value to userspace. So scramble it with XTEA using a per connection random key, known only to the kernel. Only one direction needs to be implemented, since the ID is never sent in the reverse direction. The XTEA algorithm is implemented inline since it's simple enough to do so, and this adds less complexity than if the crypto API were used. Thanks to Jesper Juhl for the idea. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:55 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
[PATCH] fuse: scramble lock owner ID VFS uses current->files pointer as lock owner ID, and it wouldn't be prudent to expose this value to userspace. So scramble it with XTEA using a per connection random key, known only to the kernel. Only one direction needs to be implemented, since the ID is never sent in the reverse direction. The XTEA algorithm is implemented inline since it's simple enough to do so, and this adds less complexity than if the crypto API were used. Thanks to Jesper Juhl for the idea. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:55 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: fuse_flush() should wait on writeback The aim of .flush fop is to hint file-system that flushing its state or caches or any other important data to reliable storage would be desirable now. fuse_flush() passes this hint by sending FUSE_FLUSH request to userspace. However, dirty pages and pages under writeback may be not visible to userspace yet if we won't ensure it explicitly. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:54 +04:00
[PATCH] vfs: add lock owner argument to flush operation Pass the POSIX lock owner ID to the flush operation. This is useful for filesystems which don't want to store any locking state in inode->i_flock but want to handle locking/unlocking POSIX locks internally. FUSE is one such filesystem but I think it possible that some network filesystems would need this also. Also add a flag to indicate that a POSIX locking request was generated by close(), so filesystems using the above feature won't send an extra locking request in this case. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 02:05:12 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: fuse_flush() should wait on writeback The aim of .flush fop is to hint file-system that flushing its state or caches or any other important data to reliable storage would be desirable now. fuse_flush() passes this hint by sending FUSE_FLUSH request to userspace. However, dirty pages and pages under writeback may be not visible to userspace yet if we won't ensure it explicitly. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:54 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: fuse_flush() should wait on writeback The aim of .flush fop is to hint file-system that flushing its state or caches or any other important data to reliable storage would be desirable now. fuse_flush() passes this hint by sending FUSE_FLUSH request to userspace. However, dirty pages and pages under writeback may be not visible to userspace yet if we won't ensure it explicitly. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:54 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: fuse_flush() should wait on writeback The aim of .flush fop is to hint file-system that flushing its state or caches or any other important data to reliable storage would be desirable now. fuse_flush() passes this hint by sending FUSE_FLUSH request to userspace. However, dirty pages and pages under writeback may be not visible to userspace yet if we won't ensure it explicitly. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:54 +04:00
fuse: use filemap_check_errors() Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 14:10:57 +02:00
fuse: fuse_flush must check mapping->flags for errors fuse_flush() calls write_inode_now() that triggers writeback, but actual writeback will happen later, on fuse_sync_writes(). If an error happens, fuse_writepage_end() will set error bit in mapping->flags. So, we have to check mapping->flags after fuse_sync_writes(). Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: <stable@vger.kernel.org> # v3.15+
2016-07-19 18:12:26 -07:00
fuse: categorize fuse_get_req() The patch categorizes all fuse_get_req() invocations into two categories: - fuse_get_req_nopages(fc) - when caller doesn't care about req->pages - fuse_get_req(fc, n) - when caller need n page pointers (n > 0) Adding fuse_get_req_nopages() helps to avoid numerous fuse_get_req(fc, 0) scattered over code. Now it's clear from the first glance when a caller need fuse_req with page pointers. The patch doesn't make any logic changes. In multi-page case, it silly allocates array of FUSE_MAX_PAGES_PER_REQ page pointers. This will be amended by future patches. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:30 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: scramble lock owner ID VFS uses current->files pointer as lock owner ID, and it wouldn't be prudent to expose this value to userspace. So scramble it with XTEA using a per connection random key, known only to the kernel. Only one direction needs to be implemented, since the ID is never sent in the reverse direction. The XTEA algorithm is implemented inline since it's simple enough to do so, and this adds less complexity than if the crypto API were used. Thanks to Jesper Juhl for the idea. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:55 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
drop unused dentry argument to ->fsync Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-26 17:53:25 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: clean up fsync Don't need to start I/O twice (once without i_mutex and one within). Also make sure that even if the userspace filesystem doesn't support FSYNC we do all the steps other than sending the message. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: fsync() did not return IO errors Due to implementation of fuse writeback filemap_write_and_wait_range() does not catch errors. We have to do this directly after fuse_sync_writes() Signed-off-by: Alexey Kuznetsov <kuznet@virtuozzo.com> Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: <stable@vger.kernel.org> # v3.15+
2016-07-19 12:48:01 -07:00
fuse: use filemap_check_errors() Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 14:10:57 +02:00
fuse: fsync() did not return IO errors Due to implementation of fuse writeback filemap_write_and_wait_range() does not catch errors. We have to do this directly after fuse_sync_writes() Signed-off-by: Alexey Kuznetsov <kuznet@virtuozzo.com> Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: <stable@vger.kernel.org> # v3.15+
2016-07-19 12:48:01 -07:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: clean up fsync Don't need to start I/O twice (once without i_mutex and one within). Also make sure that even if the userspace filesystem doesn't support FSYNC we do all the steps other than sending the message. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] FUSE: add fsync operation for directories This patch adds a new FSYNCDIR request, which is sent when fsync is called on directories. This operation is available in libfuse 2.3-pre1 or greater. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:38 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
[PATCH] FUSE: add fsync operation for directories This patch adds a new FSYNCDIR request, which is sent when fsync is called on directories. This operation is available in libfuse 2.3-pre1 or greater. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:38 -07:00
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-16 20:44:56 -04:00
[PATCH] FUSE: add fsync operation for directories This patch adds a new FSYNCDIR request, which is sent when fsync is called on directories. This operation is available in libfuse 2.3-pre1 or greater. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:38 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: pass open flags to read and write Some open flags (O_APPEND, O_DIRECT) can be changed with fcntl(F_SETFL, ...) after open, but fuse currently only sends the flags to userspace in open. To make it possible to correcly handle changing flags, send the current value to userspace in each read and write. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:22:00 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: READ request initialization Add a separate function for filling in the READ request. This will make it possible to send asynchronous READ requests as well as synchronous ones. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:45 -08:00
fuse: pass open flags to read and write Some open flags (O_APPEND, O_DIRECT) can be changed with fcntl(F_SETFL, ...) after open, but fuse currently only sends the flags to userspace in open. To make it possible to correcly handle changing flags, send the current value to userspace in each read and write. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:22:00 -08:00
[PATCH] fuse: READ request initialization Add a separate function for filling in the READ request. This will make it possible to send asynchronous READ requests as well as synchronous ones. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:45 -08:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: direct-io: don't dirty ITER_BVEC pages When reading from a loop device backed by a fuse file it deadlocks on lock_page(). This is because the page is already locked by the read() operation done on the loop device. In this case we don't want to either lock the page or dirty it. So do what fs/direct-io.c does: only dirty the page for ITER_IOVEC vectors. Reported-by: Sheng Yang <sheng@yasker.org> Fixes: aa4d86163e4e ("block: loop: switch to VFS ITER_BVEC") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.1+ Reviewed-by: Sheng Yang <sheng@yasker.org> Reviewed-by: Ashish Samant <ashish.samant@oracle.com> Tested-by: Sheng Yang <sheng@yasker.org> Tested-by: Ashish Samant <ashish.samant@oracle.com>
2016-08-24 18:17:04 +02:00
fuse: move fuse_release_user_pages() up fuse_release_user_pages() will be indirectly used by fuse_send_read/write in future patches. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:25 +04:00
fuse: direct-io: don't dirty ITER_BVEC pages When reading from a loop device backed by a fuse file it deadlocks on lock_page(). This is because the page is already locked by the read() operation done on the loop device. In this case we don't want to either lock the page or dirty it. So do what fs/direct-io.c does: only dirty the page for ITER_IOVEC vectors. Reported-by: Sheng Yang <sheng@yasker.org> Fixes: aa4d86163e4e ("block: loop: switch to VFS ITER_BVEC") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.1+ Reviewed-by: Sheng Yang <sheng@yasker.org> Reviewed-by: Ashish Samant <ashish.samant@oracle.com> Tested-by: Sheng Yang <sheng@yasker.org> Tested-by: Ashish Samant <ashish.samant@oracle.com>
2016-08-24 18:17:04 +02:00
fuse: move fuse_release_user_pages() up fuse_release_user_pages() will be indirectly used by fuse_send_read/write in future patches. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:25 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fs: split generic and aio kiocb Most callers in the kernel want to perform synchronous file I/O, but still have to bloat the stack with a full struct kiocb. Split out the parts needed in filesystem code from those in the aio code, and only allocate those needed to pass down argument on the stack. The aio code embedds the generic iocb in the one it allocates and can easily get back to it by using container_of. Also add a ->ki_complete method to struct kiocb, this is used to call into the aio code and thus removes the dependency on aio for filesystems impementing asynchronous operations. It will also allow other callers to substitute their own completion callback. We also add a new ->ki_flags field to work around the nasty layering violation recently introduced in commit 5e33f6 ("usb: gadget: ffs: add eventfd notification about ffs events"). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:49:06 +01:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: add support of async IO The patch implements a framework to process an IO request asynchronously. The idea is to associate several fuse requests with a single kiocb by means of fuse_io_priv structure. The structure plays the same role for FUSE as 'struct dio' for direct-io.c. The framework is supposed to be used like this: - someone (who wants to process an IO asynchronously) allocates fuse_io_priv and initializes it setting 'async' field to non-zero value. - as soon as fuse request is filled, it can be submitted (in non-blocking way) by fuse_async_req_send() - when all submitted requests are ACKed by userspace, io->reqs drops to zero triggering aio_complete() In case of IO initiated by libaio, aio_complete() will finish processing the same way as in case of dio_complete() calling aio_complete(). But the framework may be also used for internal FUSE use when initial IO request was synchronous (from user perspective), but it's beneficial to process it asynchronously. Then the caller should wait on kiocb explicitly and aio_complete() will wake the caller up. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:41 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] fuse: READ request initialization Add a separate function for filling in the READ request. This will make it possible to send asynchronous READ requests as well as synchronous ones. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:45 -08:00
[PATCH] fuse: transfer readdir data through device This patch removes a long lasting "hack" in FUSE, which used a separate channel (a file descriptor refering to a disk-file) to transfer directory contents from userspace to the kernel. The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which have semantics and implementation exactly maching the respective file operations (OPEN, READ, RELEASE). This simplifies the directory reading code. Also disk space is not necessary, which can be important in embedded systems. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:36 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: hotfix truncate_pagecache() issue The way how fuse calls truncate_pagecache() from fuse_change_attributes() is completely wrong. Because, w/o i_mutex held, we never sure whether 'oldsize' and 'attr->size' are valid by the time of execution of truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we released fc->lock in the middle of fuse_change_attributes(), we completely loose control of actions which may happen with given inode until we reach truncate_pagecache. The list of potentially dangerous actions includes mmap-ed reads and writes, ftruncate(2) and write(2) extending file size. The typical outcome of doing truncate_pagecache() with outdated arguments is data corruption from user point of view. This is (in some sense) acceptable in cases when the issue is triggered by a change of the file on the server (i.e. externally wrt fuse operation), but it is absolutely intolerable in scenarios when a single fuse client modifies a file without any external intervention. A real life case I discovered by fsx-linux looked like this: 1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends FUSE_SETATTR to the server synchronously, but before getting fc->lock ... 2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP to the server synchronously, then calls fuse_change_attributes(). The latter updates i_size, releases fc->lock, but before comparing oldsize vs attr->size.. 3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and updating attributes and i_size, but now oldsize is equal to outarg.attr.size because i_size has just been updated (step 2). Hence, fuse_do_setattr() returns w/o calling truncate_pagecache(). 4. As soon as ftruncate(2) completes, the user extends file size by write(2) making a hole in the middle of file, then reads data from the hole either by read(2) or mmap-ed read. The user expects to get zero data from the hole, but gets stale data because truncate_pagecache() is not executed yet. The scenario above illustrates one side of the problem: not truncating the page cache even though we should. Another side corresponds to truncating page cache too late, when the state of inode changed significantly. Theoretically, the following is possible: 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size changed (due to our own fuse_do_setattr()) and is going to call truncate_pagecache() for some 'new_size' it believes valid right now. But by the time that particular truncate_pagecache() is called ... 2. fuse_do_setattr() returns (either having called truncate_pagecache() or not -- it doesn't matter). 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). 4. mmap-ed write makes a page in the extended region dirty. The result will be the lost of data user wrote on the fourth step. The patch is a hotfix resolving the issue in a simplistic way: let's skip dangerous i_size update and truncate_pagecache if an operation changing file size is in progress. This simplistic approach looks correct for the cases w/o external changes. And to handle them properly, more sophisticated and intrusive techniques (e.g. NFS-like one) would be required. I'd like to postpone it until the issue is well discussed on the mailing list(s). Changed in v2: - improved patch description to cover both sides of the issue. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-08-30 17:06:04 +04:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: Trust kernel i_size only Make fuse think that when writeback is on the inode's i_size is always up-to-date and not update it with the value received from the userspace. This is done because the page cache code may update i_size without letting the FS know. This assumption implies fixing the previously introduced short-read helper -- when a short read occurs the 'hole' is filled with zeroes. fuse_file_fallocate() is also fixed because now we should keep i_size up to date, so it must be updated if FUSE_FALLOCATE request succeeded. Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:46 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: Trust kernel i_size only Make fuse think that when writeback is on the inode's i_size is always up-to-date and not update it with the value received from the userspace. This is done because the page cache code may update i_size without letting the FS know. This assumption implies fixing the previously introduced short-read helper -- when a short read occurs the 'hole' is filled with zeroes. fuse_file_fallocate() is also fixed because now we should keep i_size up to date, so it must be updated if FUSE_FALLOCATE request succeeded. Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:46 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Trust kernel i_size only Make fuse think that when writeback is on the inode's i_size is always up-to-date and not update it with the value received from the userspace. This is done because the page cache code may update i_size without letting the FS know. This assumption implies fixing the previously introduced short-read helper -- when a short read occurs the 'hole' is filled with zeroes. fuse_file_fallocate() is also fixed because now we should keep i_size up to date, so it must be updated if FUSE_FALLOCATE request succeeded. Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:46 +04:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: restructure fuse_readpage() Move the code filling and sending read request to a separate function. Future patches will use it for .write_begin -- partial modification of a page requires reading the page from the storage very similarly to what fuse_readpage does. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:25 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
Fix common misspellings Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-30 22:57:33 -03:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: categorize fuse_get_req() The patch categorizes all fuse_get_req() invocations into two categories: - fuse_get_req_nopages(fc) - when caller doesn't care about req->pages - fuse_get_req(fc, n) - when caller need n page pointers (n > 0) Adding fuse_get_req_nopages() helps to avoid numerous fuse_get_req(fc, 0) scattered over code. Now it's clear from the first glance when a caller need fuse_req with page pointers. The patch doesn't make any logic changes. In multi-page case, it silly allocates array of FUSE_MAX_PAGES_PER_REQ page pointers. This will be amended by future patches. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:30 +04:00
[PATCH] fuse: clean up request accounting FUSE allocated most requests from a fixed size pool filled at mount time. However in some cases (release/forget) non-pool requests were used. File locking operations aren't well served by the request pool, since they may block indefinetly thus exhausting the pool. This patch removes the request pool and always allocates requests on demand. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:58 -07:00
fuse: restructure fuse_readpage() Move the code filling and sending read request to a separate function. Future patches will use it for .write_begin -- partial modification of a page requires reading the page from the storage very similarly to what fuse_readpage does. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:25 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: restructure fuse_readpage() Move the code filling and sending read request to a separate function. Future patches will use it for .write_begin -- partial modification of a page requires reading the page from the storage very similarly to what fuse_readpage does. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:25 +04:00
fuse: don't invalidate attrs when not using atime Various read operations (e.g. readlink, readdir) invalidate the cached attrs for atime changes. This patch adds a new function 'fuse_invalidate_atime', which checks for a read-only super block and avoids the attr invalidation in that case. Signed-off-by: Andrew Gallagher <andrewjcg@fb.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 03:55:43 -08:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
fuse: Prepare to handle short reads A helper which gets called when read reports less bytes than was requested. See patch "trust kernel i_size only" for details. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:16 +04:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
fuse: don't invalidate attrs when not using atime Various read operations (e.g. readlink, readdir) invalidate the cached attrs for atime changes. This patch adds a new function 'fuse_invalidate_atime', which checks for a read-only super block and avoids the attr invalidation in that case. Signed-off-by: Andrew Gallagher <andrewjcg@fb.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 03:55:43 -08:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
fuse: fix hang of single threaded fuseblk filesystem Single threaded NTFS-3G could get stuck if a delayed RELEASE reply triggered a DESTROY request via path_put(). Fix this by a) making RELEASE requests synchronous, whenever possible, on fuseblk filesystems b) if not possible (triggered by an asynchronous read/write) then do the path_put() in a separate thread with schedule_work(). Reported-by: Oliver Neukum <oneukum@suse.de> Cc: stable@kernel.org Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-25 14:44:58 +01:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
[PATCH] fuse: use asynchronous READ requests for readpages This patch changes fuse_readpages() to send READ requests asynchronously. This makes it possible for userspace filesystems to utilize the kernel readahead logic instead of having to implement their own (resulting in double caching). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 22:14:46 -08:00
fuse: allow splice to move pages When splicing buffers to the fuse device with SPLICE_F_MOVE, try to move pages from the pipe buffer into the page cache. This allows populating the fuse filesystem's cache without ever touching the page contents, i.e. zero copy read capability. The following steps are performed when trying to move a page into the page cache: - buf->ops->confirm() to make sure the new page is uptodate - buf->ops->steal() to try to remove the new page from it's previous place - remove_from_page_cache() on the old page - add_to_page_cache_locked() on the new page If any of the above steps fail (non fatally) then the code falls back to copying the page. In particular ->steal() will fail if there are external references (other than the page cache and the pipe buffer) to the page. Also since the remove_from_page_cache() + add_to_page_cache_locked() are non-atomic it is possible that the page cache is repopulated in between the two and add_to_page_cache_locked() will fail. This could be fixed by creating a new atomic replace_page_cache_page() function. fuse_readpages_end() needed to be reworked so it works even if page->mapping is NULL for some or all pages which can happen if the add_to_page_cache_locked() failed. A number of sanity checks were added to make sure the stolen pages don't have weird flags set, etc... These could be moved into generic splice/steal code. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-05-25 15:06:07 +02:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: update file size on short read If the READ request returned a short count, then either - cached size is incorrect - filesystem is buggy, as short reads are only allowed on EOF So assume that the size is wrong and refresh it, so that cached read() doesn't zero fill the missing chunk. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:43 -07:00
[PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 03:04:40 -08:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
[PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 03:04:40 -08:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 03:04:40 -08:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
[PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 03:04:40 -08:00
fuse: don't let fuse_req->end() put the base reference fuse_req->end() was supposed to be put the base reference but there's no reason why it should. It only makes things more complex. Move it out of ->end() and make it the responsibility of request_end(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:54 +01:00
[PATCH] fuse: fix async read for legacy filesystems While asynchronous reads mean a performance improvement in most cases, if the filesystem assumed that reads are synchronous, then async reads may degrade performance (filesystem may receive reads out of order, which can confuse it's own readahead logic). With sshfs a 1.5 to 4 times slowdown can be measured. There's also a need for userspace filesystems to know whether asynchronous reads are supported by the kernel or not. To achive these, negotiate in the INIT request whether async reads will be used and the maximum readahead value. Update interface version to 7.6 If userspace uses a version earlier than 7.6, then disable async reads, and set maximum readahead value to the maximum read size, as done in previous versions. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 03:04:40 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: pass open flags to read and write Some open flags (O_APPEND, O_DIRECT) can be changed with fcntl(F_SETFL, ...) after open, but fuse currently only sends the flags to userspace in open. To make it possible to correcly handle changing flags, send the current value to userspace in each read and write. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:22:00 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: make request allocations for background processing explicit There are two types of processing requests in FUSE: synchronous (via fuse_request_send()) and asynchronous (via adding to fc->bg_queue). Fortunately, the type of processing is always known in advance, at the time of request allocation. This preparatory patch utilizes this fact making fuse_get_req() aware about the type. Next patches will use it. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-03-21 18:02:04 +04:00
[PATCH] fuse: clean up request accounting FUSE allocated most requests from a fixed size pool filled at mount time. However in some cases (release/forget) non-pool requests were used. File locking operations aren't well served by the request pool, since they may block indefinetly thus exhausting the pool. This patch removes the request pool and always allocates requests on demand. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:58 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
[PATCH] fuse: clean up request accounting FUSE allocated most requests from a fixed size pool filled at mount time. However in some cases (release/forget) non-pool requests were used. File locking operations aren't well served by the request pool, since they may block indefinetly thus exhausting the pool. This patch removes the request pool and always allocates requests on demand. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:58 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: style fixes Fix coding style errors reported by checkpatch and others. Uptdate copyright date to 2008. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:54 +01:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: add reference counting to fuse_file Make lifetime of 'struct fuse_file' independent from 'struct file' by adding a reference counter and destructor. This will enable asynchronous page writeback, where it cannot be guaranteed, that the file is not released while a request with this file handle is being served. The actual RELEASE request is only sent when there are no more references to the fuse_file. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:31:00 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
[PATCH] fuse: fix error case in fuse_readpages Don't let fuse_readpages leave the @pages list not empty when exiting on error. [akpm@osdl.org: kernel-doc fixes] Signed-off-by: Alexander Zarochentsev <zam@namesys.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-13 23:24:27 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
[PATCH] fuse: ->readpages() cleanup This just ignore the remaining pages. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Steven French <sfrench@us.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-02 22:07:09 -08:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
fuse: pass open flags to read and write Some open flags (O_APPEND, O_DIRECT) can be changed with fcntl(F_SETFL, ...) after open, but fuse currently only sends the flags to userspace in open. To make it possible to correcly handle changing flags, send the current value to userspace in each read and write. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:22:00 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: make request allocations for background processing explicit There are two types of processing requests in FUSE: synchronous (via fuse_request_send()) and asynchronous (via adding to fc->bg_queue). Fortunately, the type of processing is always known in advance, at the time of request allocation. This preparatory patch utilizes this fact making fuse_get_req() aware about the type. Next patches will use it. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-03-21 18:02:04 +04:00
fuse: rework fuse_readpages() The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the number of page pointers to allocate. This can be improved further by taking in consideration fc->max_read and gaps between page indices, but it's not clear whether it's worthy or not. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:51 +04:00
[PATCH] fuse: fix error case in fuse_readpages Don't let fuse_readpages leave the @pages list not empty when exiting on error. [akpm@osdl.org: kernel-doc fixes] Signed-off-by: Alexander Zarochentsev <zam@namesys.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-13 23:24:27 -07:00
[PATCH] fuse: clean up request accounting FUSE allocated most requests from a fixed size pool filled at mount time. However in some cases (release/forget) non-pool requests were used. File locking operations aren't well served by the request pool, since they may block indefinetly thus exhausting the pool. This patch removes the request pool and always allocates requests on demand. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:58 -07:00
[PATCH] fuse: ->readpages() cleanup This just ignore the remaining pages. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Steven French <sfrench@us.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-02 22:07:09 -08:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
[PATCH] fuse: fix oops in fuse_send_readpages() During heavy parallel filesystem activity it was possible to Oops the kernel. The reason is that read_cache_pages() could skip pages which have already been inserted into the cache by another task. Occasionally this may result in zero pages actually being sent, while fuse_send_readpages() relies on at least one page being in the request. So check this corner case and just free the request instead of trying to send it. Reported and tested by Konstantin Isakov. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:49 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] fuse: fix oops in fuse_send_readpages() During heavy parallel filesystem activity it was possible to Oops the kernel. The reason is that read_cache_pages() could skip pages which have already been inserted into the cache by another task. Occasionally this may result in zero pages actually being sent, while fuse_send_readpages() relies on at least one page being in the request. So check this corner case and just free the request instead of trying to send it. Reported and tested by Konstantin Isakov. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:49 -07:00
[PATCH] fuse: ->readpages() cleanup This just ignore the remaining pages. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Steven French <sfrench@us.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-02 22:07:09 -08:00
[PATCH] fuse: fix error case in fuse_readpages Don't let fuse_readpages leave the @pages list not empty when exiting on error. [akpm@osdl.org: kernel-doc fixes] Signed-off-by: Alexander Zarochentsev <zam@namesys.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-13 23:24:27 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse_file_aio_read(): convert to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-02 14:47:09 -04:00
fuse: fix reading past EOF Currently reading a fuse file will stop at cached i_size and return EOF, even though the file might have grown since the attributes were last updated. So detect if trying to read past EOF, and refresh the attributes before continuing with the read. Thanks to mpb for the report. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:21:59 -08:00
fuse: update attributes on aio_read A fuse-based network filesystem might allow for the inode and/or file data to change unexpectedly. A local client that opens and repeatedly reads a file might never pick up on such changes and indefinitely return stale data. Always invoke fuse_update_attributes() in the read path to cause an attr revalidation when the attributes expire. This leads to a page cache invalidation if necessary and ensures fuse issues new read requests to the fuse client. The original logic (reval only on reads beyond EOF) is preserved unless the client specifies FUSE_AUTO_INVAL_DATA on init. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-16 15:23:50 -04:00
fuse: fix reading past EOF Currently reading a fuse file will stop at cached i_size and return EOF, even though the file might have grown since the attributes were last updated. So detect if trying to read past EOF, and refresh the attributes before continuing with the read. Thanks to mpb for the report. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:21:59 -08:00
fuse: update attributes on aio_read A fuse-based network filesystem might allow for the inode and/or file data to change unexpectedly. A local client that opens and repeatedly reads a file might never pick up on such changes and indefinitely return stale data. Always invoke fuse_update_attributes() in the read path to cause an attr revalidation when the attributes expire. This leads to a page cache invalidation if necessary and ensures fuse issues new read requests to the fuse client. The original logic (reval only on reads beyond EOF) is preserved unless the client specifies FUSE_AUTO_INVAL_DATA on init. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-16 15:23:50 -04:00
fuse_file_aio_read(): convert to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-02 14:47:09 -04:00
fuse: fix reading past EOF Currently reading a fuse file will stop at cached i_size and return EOF, even though the file might have grown since the attributes were last updated. So detect if trying to read past EOF, and refresh the attributes before continuing with the read. Thanks to mpb for the report. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:21:59 -08:00
fuse_file_aio_read(): convert to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-02 14:47:09 -04:00
fuse: fix reading past EOF Currently reading a fuse file will stop at cached i_size and return EOF, even though the file might have grown since the attributes were last updated. So detect if trying to read past EOF, and refresh the attributes before continuing with the read. Thanks to mpb for the report. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-28 16:21:59 -08:00
fuse: clean up fuse_write_fill() Move out code from fuse_write_fill() which is not common to all callers. Remove two function arguments which become unnecessary. Also remove unnecessary memset(), the request is already initialized to zero. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: clean up fuse_write_fill() Move out code from fuse_write_fill() which is not common to all callers. Remove two function arguments which become unnecessary. Also remove unnecessary memset(), the request is already initialized to zero. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: clean up fuse_write_fill() Move out code from fuse_write_fill() which is not common to all callers. Remove two function arguments which become unnecessary. Also remove unnecessary memset(), the request is already initialized to zero. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: add support for mandatory locking For mandatory locking the userspace filesystem needs to know the lock ownership for read, write and truncate operations. This patch adds the necessary fields to the protocol. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:04 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: add helper for asynchronous writes This patch adds a new helper function fuse_write_fill() which makes it possible to send WRITE requests asynchronously. A new flag for WRITE requests is also added which indicates that this a write from the page cache, and not a "normal" file write. This patch is in preparation for writable mmap support. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:03 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: clean up setting i_size in write Extract common code for setting i_size in write functions into a common helper. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: clean up setting i_size in write Extract common code for setting i_size in write functions into a common helper. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: clean up setting i_size in write Extract common code for setting i_size in write functions into a common helper. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: clean up setting i_size in write Extract common code for setting i_size in write functions into a common helper. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: clean up setting i_size in write Extract common code for setting i_size in write functions into a common helper. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: add per-page descriptor <offset, length> to fuse_req The ability to save page pointers along with lengths and offsets in fuse_req will be useful to cover several iovec-s with a single fuse_req. Per-request page_offset is removed because anybody who need it can use req->page_descs[0].offset instead. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:24 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: add per-page descriptor <offset, length> to fuse_req The ability to save page pointers along with lengths and offsets in fuse_req will be useful to cover several iovec-s with a single fuse_req. Per-request page_offset is removed because anybody who need it can use req->page_descs[0].offset instead. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:24 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fs: symlink write_begin allocation context fix With the write_begin/write_end aops, page_symlink was broken because it could no longer pass a GFP_NOFS type mask into the point where the allocations happened. They are done in write_begin, which would always assume that the filesystem can be entered from reclaim. This bug could cause filesystem deadlocks. The funny thing with having a gfp_t mask there is that it doesn't really allow the caller to arbitrarily tinker with the context in which it can be called. It couldn't ever be GFP_ATOMIC, for example, because it needs to take the page lock. The only thing any callers care about is __GFP_FS anyway, so turn that into a single flag. Add a new flag for write_begin, AOP_FLAG_NOFS. Filesystems can now act on this flag in their write_begin function. Change __grab_cache_page to accept a nofs argument as well, to honour that flag (while we're there, change the name to grab_cache_page_write_begin which is more instructive and does away with random leading underscores). This is really a more flexible way to go in the end anyway -- if a filesystem happens to want any extra allocations aside from the pagecache ones in ints write_begin function, it may now use GFP_KERNEL (rather than GFP_NOFS) for common case allocations (eg. ocfs2_alloc_write_ctxt, for a random example). [kosaki.motohiro@jp.fujitsu.com: fix ubifs] [kosaki.motohiro@jp.fujitsu.com: fix fuse] Signed-off-by: Nick Piggin <npiggin@suse.de> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <stable@kernel.org> [2.6.28.x] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Cleaned up the calling convention: just pass in the AOP flags untouched to the grab_cache_page_write_begin() function. That just simplifies everybody, and may even allow future expansion of the logic. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 12:00:53 -08:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm: flush dcache before writing into page to avoid alias The cache alias problem will happen if the changes of user shared mapping is not flushed before copying, then user and kernel mapping may be mapped into two different cache line, it is impossible to guarantee the coherence after iov_iter_copy_from_user_atomic. So the right steps should be: flush_dcache_page(page); kmap_atomic(page); write to page; kunmap_atomic(page); flush_dcache_page(page); More precisely, we might create two new APIs flush_dcache_user_page and flush_dcache_kern_page to replace the two flush_dcache_page accordingly. Here is a snippet tested on omap2430 with VIPT cache, and I think it is not ARM-specific: int val = 0x11111111; fd = open("abc", O_RDWR); addr = mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); *(addr+0) = 0x44444444; tmp = *(addr+0); *(addr+1) = 0x77777777; write(fd, &val, sizeof(int)); close(fd); The results are not always 0x11111111 0x77777777 at the beginning as expected. Sometimes we see 0x44444444 0x77777777. Signed-off-by: Anfei <anfei.zhou@gmail.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: <linux-arch@vger.kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-02 13:44:02 -08:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: break infinite loop in fuse_fill_write_pages() I got a report about unkillable task eating CPU. Further investigation shows, that the problem is in the fuse_fill_write_pages() function. If iov's first segment has zero length, we get an infinite loop, because we never reach iov_iter_advance() call. Fix this by calling iov_iter_advance() before repeating an attempt to copy data from userspace. A similar problem is described in 124d3b7041f ("fix writev regression: pan hanging unkillable and un-straceable"). If zero-length segmend is followed by segment with invalid address, iov_iter_fault_in_readable() checks only first segment (zero-length), iov_iter_copy_from_user_atomic() skips it, fails at second and returns zero -> goto again without skipping zero-length segment. Patch calls iov_iter_advance() before goto again: we'll skip zero-length segment at second iteraction and iov_iter_fault_in_readable() will detect invalid address. Special thanks to Konstantin Khlebnikov, who helped a lot with the commit description. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Maxim Patlasov <mpatlasov@parallels.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Fixes: ea9b9907b82a ("fuse: implement perform_write") Cc: <stable@vger.kernel.org>
2015-10-12 16:33:44 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: add flag to turn on big writes Prior to 2.6.26 fuse only supported single page write requests. In theory all fuse filesystem should be able support bigger than 4k writes, as there's nothing in the API to prevent it. Unfortunately there's a known case in NTFS-3G where big writes cause filesystem corruption. There could also be other filesystems, where the lack of testing with big write requests would result in bugs. To prevent such problems on a kernel upgrade, disable big writes by default, but let filesystems set a flag to turn it on. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Szabolcs Szakacsits <szaka@ntfs-3g.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-12 14:02:32 -07:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: rework fuse_perform_write() The patch allocates as many page pointers in fuse_req as needed to cover interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced to hide this cumbersome arithmetic. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:00 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: rework fuse_perform_write() The patch allocates as many page pointers in fuse_req as needed to cover interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced to hide this cumbersome arithmetic. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:00 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: rework fuse_perform_write() The patch allocates as many page pointers in fuse_req as needed to cover interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced to hide this cumbersome arithmetic. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:00 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: hotfix truncate_pagecache() issue The way how fuse calls truncate_pagecache() from fuse_change_attributes() is completely wrong. Because, w/o i_mutex held, we never sure whether 'oldsize' and 'attr->size' are valid by the time of execution of truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we released fc->lock in the middle of fuse_change_attributes(), we completely loose control of actions which may happen with given inode until we reach truncate_pagecache. The list of potentially dangerous actions includes mmap-ed reads and writes, ftruncate(2) and write(2) extending file size. The typical outcome of doing truncate_pagecache() with outdated arguments is data corruption from user point of view. This is (in some sense) acceptable in cases when the issue is triggered by a change of the file on the server (i.e. externally wrt fuse operation), but it is absolutely intolerable in scenarios when a single fuse client modifies a file without any external intervention. A real life case I discovered by fsx-linux looked like this: 1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends FUSE_SETATTR to the server synchronously, but before getting fc->lock ... 2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP to the server synchronously, then calls fuse_change_attributes(). The latter updates i_size, releases fc->lock, but before comparing oldsize vs attr->size.. 3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and updating attributes and i_size, but now oldsize is equal to outarg.attr.size because i_size has just been updated (step 2). Hence, fuse_do_setattr() returns w/o calling truncate_pagecache(). 4. As soon as ftruncate(2) completes, the user extends file size by write(2) making a hole in the middle of file, then reads data from the hole either by read(2) or mmap-ed read. The user expects to get zero data from the hole, but gets stale data because truncate_pagecache() is not executed yet. The scenario above illustrates one side of the problem: not truncating the page cache even though we should. Another side corresponds to truncating page cache too late, when the state of inode changed significantly. Theoretically, the following is possible: 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size changed (due to our own fuse_do_setattr()) and is going to call truncate_pagecache() for some 'new_size' it believes valid right now. But by the time that particular truncate_pagecache() is called ... 2. fuse_do_setattr() returns (either having called truncate_pagecache() or not -- it doesn't matter). 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). 4. mmap-ed write makes a page in the extended region dirty. The result will be the lost of data user wrote on the fourth step. The patch is a hotfix resolving the issue in a simplistic way: let's skip dangerous i_size update and truncate_pagecache if an operation changing file size is in progress. This simplistic approach looks correct for the cases w/o external changes. And to handle them properly, more sophisticated and intrusive techniques (e.g. NFS-like one) would be required. I'd like to postpone it until the issue is well discussed on the mailing list(s). Changed in v2: - improved patch description to cover both sides of the issue. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-08-30 17:06:04 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: hotfix truncate_pagecache() issue The way how fuse calls truncate_pagecache() from fuse_change_attributes() is completely wrong. Because, w/o i_mutex held, we never sure whether 'oldsize' and 'attr->size' are valid by the time of execution of truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we released fc->lock in the middle of fuse_change_attributes(), we completely loose control of actions which may happen with given inode until we reach truncate_pagecache. The list of potentially dangerous actions includes mmap-ed reads and writes, ftruncate(2) and write(2) extending file size. The typical outcome of doing truncate_pagecache() with outdated arguments is data corruption from user point of view. This is (in some sense) acceptable in cases when the issue is triggered by a change of the file on the server (i.e. externally wrt fuse operation), but it is absolutely intolerable in scenarios when a single fuse client modifies a file without any external intervention. A real life case I discovered by fsx-linux looked like this: 1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends FUSE_SETATTR to the server synchronously, but before getting fc->lock ... 2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP to the server synchronously, then calls fuse_change_attributes(). The latter updates i_size, releases fc->lock, but before comparing oldsize vs attr->size.. 3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and updating attributes and i_size, but now oldsize is equal to outarg.attr.size because i_size has just been updated (step 2). Hence, fuse_do_setattr() returns w/o calling truncate_pagecache(). 4. As soon as ftruncate(2) completes, the user extends file size by write(2) making a hole in the middle of file, then reads data from the hole either by read(2) or mmap-ed read. The user expects to get zero data from the hole, but gets stale data because truncate_pagecache() is not executed yet. The scenario above illustrates one side of the problem: not truncating the page cache even though we should. Another side corresponds to truncating page cache too late, when the state of inode changed significantly. Theoretically, the following is possible: 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size changed (due to our own fuse_do_setattr()) and is going to call truncate_pagecache() for some 'new_size' it believes valid right now. But by the time that particular truncate_pagecache() is called ... 2. fuse_do_setattr() returns (either having called truncate_pagecache() or not -- it doesn't matter). 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). 4. mmap-ed write makes a page in the extended region dirty. The result will be the lost of data user wrote on the fourth step. The patch is a hotfix resolving the issue in a simplistic way: let's skip dangerous i_size update and truncate_pagecache if an operation changing file size is in progress. This simplistic approach looks correct for the cases w/o external changes. And to handle them properly, more sophisticated and intrusive techniques (e.g. NFS-like one) would be required. I'd like to postpone it until the issue is well discussed on the mailing list(s). Changed in v2: - improved patch description to cover both sides of the issue. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-08-30 17:06:04 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: rework fuse_perform_write() The patch allocates as many page pointers in fuse_req as needed to cover interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced to hide this cumbersome arithmetic. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:00 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: rework fuse_perform_write() The patch allocates as many page pointers in fuse_req as needed to cover interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced to hide this cumbersome arithmetic. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:00 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: hotfix truncate_pagecache() issue The way how fuse calls truncate_pagecache() from fuse_change_attributes() is completely wrong. Because, w/o i_mutex held, we never sure whether 'oldsize' and 'attr->size' are valid by the time of execution of truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we released fc->lock in the middle of fuse_change_attributes(), we completely loose control of actions which may happen with given inode until we reach truncate_pagecache. The list of potentially dangerous actions includes mmap-ed reads and writes, ftruncate(2) and write(2) extending file size. The typical outcome of doing truncate_pagecache() with outdated arguments is data corruption from user point of view. This is (in some sense) acceptable in cases when the issue is triggered by a change of the file on the server (i.e. externally wrt fuse operation), but it is absolutely intolerable in scenarios when a single fuse client modifies a file without any external intervention. A real life case I discovered by fsx-linux looked like this: 1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends FUSE_SETATTR to the server synchronously, but before getting fc->lock ... 2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP to the server synchronously, then calls fuse_change_attributes(). The latter updates i_size, releases fc->lock, but before comparing oldsize vs attr->size.. 3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and updating attributes and i_size, but now oldsize is equal to outarg.attr.size because i_size has just been updated (step 2). Hence, fuse_do_setattr() returns w/o calling truncate_pagecache(). 4. As soon as ftruncate(2) completes, the user extends file size by write(2) making a hole in the middle of file, then reads data from the hole either by read(2) or mmap-ed read. The user expects to get zero data from the hole, but gets stale data because truncate_pagecache() is not executed yet. The scenario above illustrates one side of the problem: not truncating the page cache even though we should. Another side corresponds to truncating page cache too late, when the state of inode changed significantly. Theoretically, the following is possible: 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size changed (due to our own fuse_do_setattr()) and is going to call truncate_pagecache() for some 'new_size' it believes valid right now. But by the time that particular truncate_pagecache() is called ... 2. fuse_do_setattr() returns (either having called truncate_pagecache() or not -- it doesn't matter). 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). 4. mmap-ed write makes a page in the extended region dirty. The result will be the lost of data user wrote on the fourth step. The patch is a hotfix resolving the issue in a simplistic way: let's skip dangerous i_size update and truncate_pagecache if an operation changing file size is in progress. This simplistic approach looks correct for the cases w/o external changes. And to handle them properly, more sophisticated and intrusive techniques (e.g. NFS-like one) would be required. I'd like to postpone it until the issue is well discussed on the mailing list(s). Changed in v2: - improved patch description to cover both sides of the issue. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-08-30 17:06:04 +04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: switch to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-03 14:33:23 -04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: Turn writeback cache on Introduce a bit kernel and userspace exchange between each-other on the init stage and turn writeback on if the userspace want this and mount option 'allow_wbcache' is present (controlled by fusermount). Also add each writable file into per-inode write list and call the generic_file_aio_write to make use of the Linux page cache engine. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:18 +04:00
fuse: switch to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-03 14:33:23 -04:00
fuse: Turn writeback cache on Introduce a bit kernel and userspace exchange between each-other on the init stage and turn writeback on if the userspace want this and mount option 'allow_wbcache' is present (controlled by fusermount). Also add each writable file into per-inode write list and call the generic_file_aio_write to make use of the Linux page cache engine. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:18 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info Now that we got rid of the bdi abuse on character devices we can always use sb->s_bdi to get at the backing_dev_info for a file, except for the block device special case. Export inode_to_bdi and replace uses of mapping->backing_dev_info with it to prepare for the removal of mapping->backing_dev_info. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:36 +01:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
switch generic_write_checks() to iocb and iter ... returning -E... upon error and amount of data left in iter after (possible) truncation upon success. Note, that normal case gives a non-zero (positive) return value, so any tests for != 0 _must_ be updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: fs/ext4/file.c
2015-04-09 12:55:47 -04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fs: Rename file_remove_suid() to file_remove_privs() file_remove_suid() is a misnomer since it removes also file capabilities stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells something else than whether file_remove_suid() call is necessary which leads to bugs. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-21 16:05:53 +02:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fs: introduce inode operation ->update_time Btrfs has to make sure we have space to allocate new blocks in order to modify the inode, so updating time can fail. We've gotten around this by having our own file_update_time but this is kind of a pain, and Christoph has indicated he would like to make xfs do something different with atime updates. So introduce ->update_time, where we will deal with i_version an a/m/c time updates and indicate which changes need to be made. The normal version just does what it has always done, updates the time and marks the inode dirty, and then filesystems can choose to do something different. I've gone through all of the users of file_update_time and made them check for errors with the exception of the fault code since it's complicated and I wasn't quite sure what to do there, also Jan is going to be pushing the file time updates into page_mkwrite for those who have it so that should satisfy btrfs and make it not a big deal to check the file_update_time() return code in the generic fault path. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-03-26 09:59:21 -04:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
mirror O_APPEND and O_DIRECT into iocb->ki_flags ... avoiding write_iter/fcntl races. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-09 13:52:01 -04:00
switch generic_write_checks() to iocb and iter ... returning -E... upon error and amount of data left in iter after (possible) truncation upon success. Note, that normal case gives a non-zero (positive) return value, so any tests for != 0 _must_ be updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: fs/ext4/file.c
2015-04-09 12:55:47 -04:00
filemap: remove the pos argument to generic_file_direct_write Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-07 08:51:56 -07:00
fuse: switch to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-03 14:33:23 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: switch to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-03 14:33:23 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
switch generic_write_checks() to iocb and iter ... returning -E... upon error and amount of data left in iter after (possible) truncation upon success. Note, that normal case gives a non-zero (positive) return value, so any tests for != 0 _must_ be updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: fs/ext4/file.c
2015-04-09 12:55:47 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
switch generic_write_checks() to iocb and iter ... returning -E... upon error and amount of data left in iter after (possible) truncation upon success. Note, that normal case gives a non-zero (positive) return value, so any tests for != 0 _must_ be updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: fs/ext4/file.c
2015-04-09 12:55:47 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: implement perform_write Introduce fuse_perform_write. With fusexmp (a passthrough filesystem), large (1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times (256MB/s vs 71MB/s). [mszeredi@suse.cz]: - split into smaller functions - testing - duplicate generic_file_aio_write(), so that there's no need to add a new ->perform_write() a_op. Comment from hch. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:42 -07:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: pass iov[] to fuse_get_user_pages() The patch makes preliminary work for the next patch optimizing scatter-gather direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s to each fuse request as possible. So, here we only rework all related call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages(). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:15 +04:00
fuse: fix argument type in fuse_get_user_pages() Fix the following warning: fs/fuse/file.c: In function 'fuse_direct_io': fs/fuse/file.c:1002: warning: passing argument 3 of 'fuse_get_user_pages' from incompatible pointer type This was introduced by commit f4975c67 "fuse: allow kernel to access "direct_io" files". Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-09 17:37:52 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
fuse: pass iov[] to fuse_get_user_pages() The patch makes preliminary work for the next patch optimizing scatter-gather direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s to each fuse request as possible. So, here we only rework all related call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages(). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:15 +04:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
bio_vec-backed iov_iter New variant of iov_iter - ITER_BVEC in iter->type, backed with bio_vec array instead of iovec one. Primitives taught to deal with such beasts, __swap_write() switched to using that kind of iov_iter. Note that bio_vec is just a <page, offset, length> triple - there's nothing block-specific about it. I've left the definition where it was, but took it from under ifdef CONFIG_BLOCK. Next target: ->splice_write()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-04 23:12:29 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: pass iov[] to fuse_get_user_pages() The patch makes preliminary work for the next patch optimizing scatter-gather direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s to each fuse request as possible. So, here we only rework all related call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages(). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:15 +04:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: optimize __fuse_direct_io() __fuse_direct_io() allocates fuse-requests by calling fuse_get_req(fc, n). The patch calculates 'n' based on iov[] array. This is useful because allocating FUSE_MAX_PAGES_PER_REQ page pointers and descriptors for each fuse request would be waste of memory in case of iov-s of smaller size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:36 +04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
new helper: iov_iter_npages() counts the pages covered by iov_iter, up to given limit. do_block_direct_io() and fuse_iter_npages() switched to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-19 01:16:16 -04:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
fuse: honour max_read and max_write in direct_io mode The third argument of fuse_get_user_pages() "nbytesp" refers to the number of bytes a caller asked to pack into fuse request. This value may be lesser than capacity of fuse request or iov_iter. So fuse_get_user_pages() must ensure that *nbytesp won't grow. Now, when helper iov_iter_get_pages() performs all hard work of extracting pages from iov_iter, it can be done by passing properly calculated "maxsize" to the helper. The other caller of iov_iter_get_pages() (dio_refill_pages()) doesn't need this capability, so pass LONG_MAX as the maxsize argument here. Fixes: c9c37e2e6378 ("fuse: switch to iov_iter_get_pages()") Reported-by: Werner Baumann <werner.baumann@onlinehome.de> Tested-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-09-24 17:09:11 +02:00
switch iov_iter_get_pages() to passing maximal number of pages ... instead of maximal size. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-18 20:34:33 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: switch to iov_iter_get_pages() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 16:08:30 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: switch to iov_iter_get_pages() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 16:08:30 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: switch to iov_iter_get_pages() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 16:08:30 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: switch to iov_iter_get_pages() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 16:08:30 -04:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: Fix return value from fuse_get_user_pages() fuse_get_user_pages() should return error or 0. Otherwise fuse_direct_io read will not return 0 to indicate that read has completed. Fixes: 742f992708df ("fuse: return patrial success from fuse_direct_io()") Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-25 10:53:41 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: optimize __fuse_direct_io() __fuse_direct_io() allocates fuse-requests by calling fuse_get_req(fc, n). The patch calculates 'n' based on iov[] array. This is useful because allocating FUSE_MAX_PAGES_PER_REQ page pointers and descriptors for each fuse request would be waste of memory in case of iov-s of smaller size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:36 +04:00
new helper: iov_iter_npages() counts the pages covered by iov_iter, up to given limit. do_block_direct_io() and fuse_iter_npages() switched to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-19 01:16:16 -04:00
fuse: optimize __fuse_direct_io() __fuse_direct_io() allocates fuse-requests by calling fuse_get_req(fc, n). The patch calculates 'n' based on iov[] array. This is useful because allocating FUSE_MAX_PAGES_PER_REQ page pointers and descriptors for each fuse request would be waste of memory in case of iov-s of smaller size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:36 +04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: direct-io: don't dirty ITER_BVEC pages When reading from a loop device backed by a fuse file it deadlocks on lock_page(). This is because the page is already locked by the read() operation done on the loop device. In this case we don't want to either lock the page or dirty it. So do what fs/direct-io.c does: only dirty the page for ITER_IOVEC vectors. Reported-by: Sheng Yang <sheng@yasker.org> Fixes: aa4d86163e4e ("block: loop: switch to VFS ITER_BVEC") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.1+ Reviewed-by: Sheng Yang <sheng@yasker.org> Reviewed-by: Ashish Samant <ashish.samant@oracle.com> Tested-by: Sheng Yang <sheng@yasker.org> Tested-by: Ashish Samant <ashish.samant@oracle.com>
2016-08-24 18:17:04 +02:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
[PATCH] fuse: fail file operations on bad inode Make file operations on a bad inode fail. This just makes things a bit more consistent. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 00:19:39 -08:00
fuse: allocate for_background dio requests based on io->async state Commit 8b41e671 introduced explicit background checking for fuse_req structures with BUG_ON() checks for the appropriate type of request in in the associated send functions. Commit bcba24cc introduced the ability to send dio requests as background requests but does not update the request allocation based on the type of I/O request. As a result, a BUG_ON() triggers in the fuse_request_send_background() background path if an async I/O is sent. Allocate a request based on the async state of the fuse_io_priv to avoid the BUG. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-14 11:25:39 -04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
fuse: allocate for_background dio requests based on io->async state Commit 8b41e671 introduced explicit background checking for fuse_req structures with BUG_ON() checks for the appropriate type of request in in the associated send functions. Commit bcba24cc introduced the ability to send dio requests as background requests but does not update the request allocation based on the type of I/O request. As a result, a BUG_ON() triggers in the fuse_request_send_background() background path if an async I/O is sent. Allocate a request based on the async state of the fuse_io_priv to avoid the BUG. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-14 11:25:39 -04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
[PATCH] fuse: clean up request accounting FUSE allocated most requests from a fixed size pool filled at mount time. However in some cases (release/forget) non-pool requests were used. File locking operations aren't well served by the request pool, since they may block indefinetly thus exhausting the pool. This patch removes the request pool and always allocates requests on demand. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-10 22:54:58 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: Fix O_DIRECT operations vs cached writeback misorder The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:12:05 +04:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: don't use inode in helpers called by fuse_direct_io() Use ff->fc and ff->nodeid instead of passing down the inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: direct-io: don't dirty ITER_BVEC pages When reading from a loop device backed by a fuse file it deadlocks on lock_page(). This is because the page is already locked by the read() operation done on the loop device. In this case we don't want to either lock the page or dirty it. So do what fs/direct-io.c does: only dirty the page for ITER_IOVEC vectors. Reported-by: Sheng Yang <sheng@yasker.org> Fixes: aa4d86163e4e ("block: loop: switch to VFS ITER_BVEC") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # v4.1+ Reviewed-by: Sheng Yang <sheng@yasker.org> Reviewed-by: Ashish Samant <ashish.samant@oracle.com> Tested-by: Sheng Yang <sheng@yasker.org> Tested-by: Ashish Samant <ashish.samant@oracle.com>
2016-08-24 18:17:04 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
[fuse] Direct I/O should not use fuse_reset_request It's cleaner to allocate a new request, otherwise the uid/gid/pid fields of the request won't be filled in. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2006-04-11 21:16:51 +02:00
fuse: allocate for_background dio requests based on io->async state Commit 8b41e671 introduced explicit background checking for fuse_req structures with BUG_ON() checks for the appropriate type of request in in the associated send functions. Commit bcba24cc introduced the ability to send dio requests as background requests but does not update the request allocation based on the type of I/O request. As a result, a BUG_ON() triggers in the fuse_request_send_background() background path if an async I/O is sent. Allocate a request based on the async state of the fuse_io_priv to avoid the BUG. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-14 11:25:39 -04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
fuse: allocate for_background dio requests based on io->async state Commit 8b41e671 introduced explicit background checking for fuse_req structures with BUG_ON() checks for the appropriate type of request in in the associated send functions. Commit bcba24cc introduced the ability to send dio requests as background requests but does not update the request allocation based on the type of I/O request. As a result, a BUG_ON() triggers in the fuse_request_send_background() background path if an async I/O is sent. Allocate a request based on the async state of the fuse_io_priv to avoid the BUG. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-14 11:25:39 -04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
[fuse] Direct I/O should not use fuse_reset_request It's cleaner to allocate a new request, otherwise the uid/gid/pid fields of the request won't be filled in. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2006-04-11 21:16:51 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: prevent fuse_put_request on invalid pointer fuse_direct_io() has a loop where requests are allocated in each iteration. if allocation fails, the loop is broken out and follows into an unconditional fuse_put_request() on that invalid pointer. Signed-off-by: Anand V. Avati <avati@gluster.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@kernel.org
2009-10-22 06:24:52 -07:00
fuse: prepare fuse_direct_io() for CUSE Move code operating on the inode out from fuse_direct_io(). This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: return patrial success from fuse_direct_io() If a user calls writev/readv in direct io mode with partially valid data in the iovec array such that any vector other than the first one in the array contains invalid data, we currently return the error for the invalid iovec. Instead, we should return the number of bytes already written/read and not the error as we do in the non direct_io case. Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14 21:57:35 -07:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: prepare fuse_direct_io() for CUSE Move code operating on the inode out from fuse_direct_io(). This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
fuse: prepare fuse_direct_io() for CUSE Move code operating on the inode out from fuse_direct_io(). This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
fuse: prepare fuse_direct_io() for CUSE Move code operating on the inode out from fuse_direct_io(). This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
fuse: pass iov[] to fuse_get_user_pages() The patch makes preliminary work for the next patch optimizing scatter-gather direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s to each fuse request as possible. So, here we only rework all related call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages(). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:15 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
fuse: pass iov[] to fuse_get_user_pages() The patch makes preliminary work for the next patch optimizing scatter-gather direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s to each fuse request as possible. So, here we only rework all related call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages(). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:15 +04:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
switch generic_write_checks() to iocb and iter ... returning -E... upon error and amount of data left in iter after (possible) truncation upon success. Note, that normal case gives a non-zero (positive) return value, so any tests for != 0 _must_ be updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Conflicts: fs/ext4/file.c
2015-04-09 12:55:47 -04:00
expand __fuse_direct_write() in both callers it's actually shorter that way *and* later we'll want iocb in scope of generic_write_check() caller. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:15:58 -04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info Now that we got rid of the bdi abuse on character devices we can always use sb->s_bdi to get at the backing_dev_info for a file, except for the block device special case. Export inode_to_bdi and replace uses of mapping->backing_dev_info with it to prepare for the removal of mapping->backing_dev_info. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:36 +01:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
mm: move most file-based accounting to the node There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 15:46:20 -07:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: writepages: crop secondary requests If writeback happens while fuse is in FUSE_NOWRITE condition, the request will be queued but not processed immediately (see fuse_flush_writepages()). Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will be queued as "secondary" requests to that first ("primary") request. Existing implementation crops only primary request. This is not correct because a subsequent extending write(2) may increase i_size and then secondary requests won't be cropped properly. The result would be stale data written to the server to a file offset where zeros must be. Similar problem may happen if secondary requests are attached to an in-flight request that was already cropped. The patch solves the issue by cropping all secondary requests in fuse_writepage_end(). Thanks to Miklos for idea. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:32 +04:00
fuse: fix lock annotations Sparse doesn't understand lock annotations of the form __releases(&foo->lock). Change them to __releases(foo->lock). Same for __acquires(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-09-07 13:42:41 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Prepare to handle multiple pages in writeback The .writepages callback will issue writeback requests with more than one page aboard. Make existing end/check code be aware of this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:48 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: don't let fuse_req->end() put the base reference fuse_req->end() was supposed to be put the base reference but there's no reason why it should. It only makes things more complex. Move it out of ->end() and make it the responsibility of request_end(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:54 +01:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: fix lock annotations Sparse doesn't understand lock annotations of the form __releases(&foo->lock). Change them to __releases(foo->lock). Same for __acquires(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2010-09-07 13:42:41 +02:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: writepages: crop secondary requests If writeback happens while fuse is in FUSE_NOWRITE condition, the request will be queued but not processed immediately (see fuse_flush_writepages()). Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will be queued as "secondary" requests to that first ("primary") request. Existing implementation crops only primary request. This is not correct because a subsequent extending write(2) may increase i_size and then secondary requests won't be cropped properly. The result would be stale data written to the server to a file offset where zeros must be. Similar problem may happen if secondary requests are attached to an in-flight request that was already cropped. The patch solves the issue by cropping all secondary requests in fuse_writepage_end(). Thanks to Miklos for idea. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:32 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: writepages: crop secondary requests If writeback happens while fuse is in FUSE_NOWRITE condition, the request will be queued but not processed immediately (see fuse_flush_writepages()). Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will be queued as "secondary" requests to that first ("primary") request. Existing implementation crops only primary request. This is not correct because a subsequent extending write(2) may increase i_size and then secondary requests won't be cropped properly. The result would be stale data written to the server to a file offset where zeros must be. Similar problem may happen if secondary requests are attached to an in-flight request that was already cropped. The patch solves the issue by cropping all secondary requests in fuse_writepage_end(). Thanks to Miklos for idea. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:32 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: crop secondary requests If writeback happens while fuse is in FUSE_NOWRITE condition, the request will be queued but not processed immediately (see fuse_flush_writepages()). Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will be queued as "secondary" requests to that first ("primary") request. Existing implementation crops only primary request. This is not correct because a subsequent extending write(2) may increase i_size and then secondary requests won't be cropped properly. The result would be stale data written to the server to a file offset where zeros must be. Similar problem may happen if secondary requests are attached to an in-flight request that was already cropped. The patch solves the issue by cropping all secondary requests in fuse_writepage_end(). Thanks to Miklos for idea. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:32 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: protect secondary requests from fuse file release All async fuse requests must be supplied with extra reference to a fuse file. This is necessary to ensure that the fuse file is not released until all in-flight requests are completed. Fuse secondary writeback requests must obey this rule as well. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:54 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: crop secondary requests If writeback happens while fuse is in FUSE_NOWRITE condition, the request will be queued but not processed immediately (see fuse_flush_writepages()). Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will be queued as "secondary" requests to that first ("primary") request. Existing implementation crops only primary request. This is not correct because a subsequent extending write(2) may increase i_size and then secondary requests won't be cropped properly. The result would be stale data written to the server to a file offset where zeros must be. Similar problem may happen if secondary requests are attached to an in-flight request that was already cropped. The patch solves the issue by cropping all secondary requests in fuse_writepage_end(). Thanks to Miklos for idea. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:32 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: Getting file for writeback helper There will be a .writepageS callback implementation which will need to get a fuse_file out of a fuse_inode, thus make a helper for this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:20 +04:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: Getting file for writeback helper There will be a .writepageS callback implementation which will need to get a fuse_file out of a fuse_inode, thus make a helper for this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:20 +04:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: Getting file for writeback helper There will be a .writepageS callback implementation which will need to get a fuse_file out of a fuse_inode, thus make a helper for this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:20 +04:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: allow ctime flushing to userspace The patch extends fuse_setattr_in, and extends the flush procedure (fuse_flush_times()) called on ->write_inode() to send the ctime as well as mtime. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:24 +02:00
fuse: add .write_inode ...and flush mtime from this. This allows us to use the kernel infrastructure for writing out dirty metadata (mtime at this point, but ctime in the next patches and also maybe atime). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:23 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: general infrastructure for pages[] of variable size The patch removes inline array of FUSE_MAX_PAGES_PER_REQ page pointers from fuse_req. Instead of that, req->pages may now point either to small inline array or to an array allocated dynamically. This essentially means that all callers of fuse_request_alloc[_nofs] should pass the number of pages needed explicitly. The patch doesn't make any logic changes. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:48:07 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: release temporary page if fuse_writepage_locked() failed tmp_page to be freed if fuse_write_file_get() returns NULL. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-07-10 15:32:43 +04:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: Getting file for writeback helper There will be a .writepageS callback implementation which will need to get a fuse_file out of a fuse_inode, thus make a helper for this. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:42:20 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: clean up fuse_write_fill() Move out code from fuse_write_fill() which is not common to all callers. Remove two function arguments which become unnecessary. Also remove unnecessary memset(), the request is already initialized to zero. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: allow kernel to access "direct_io" files Allow the kernel read and write on "direct_io" files. This is necessary for nfs export and execute support. The implementation is simple: if an access from the kernel is detected, don't perform get_user_pages(), just use the kernel address provided by the requester to copy from/to the userspace filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: add per-page descriptor <offset, length> to fuse_req The ability to save page pointers along with lengths and offsets in fuse_req will be useful to cover several iovec-s with a single fuse_req. Per-request page_offset is removed because anybody who need it can use req->page_descs[0].offset instead. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:24 +04:00
fuse: use req->page_descs[] for argpages cases Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:33 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
mm: move most file-based accounting to the node There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 15:46:20 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: postpone end_page_writeback() in fuse_writepage_locked() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepage_locked fills FUSE_WRITE request and releases the original page by end_page_writeback. 4) fuse_do_setattr() completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepage_locked proceeds by queueing FUSE_WRITE request. fuse_send_writepage is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback to the end of fuse_writepage_locked fixes the race because now the fact that truncate_pagecache is successfully returned infers that fuse_writepage_locked has already called end_page_writeback. And this, in turn, infers that fuse_flush_writepages has already called fuse_send_writepage, and the latter used valid (shrunk) i_size. write(2) could not extend it because of i_mutex held by ftruncate(2). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-08-12 20:39:30 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: release temporary page if fuse_writepage_locked() failed tmp_page to be freed if fuse_write_file_get() returns NULL. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-07-10 15:32:43 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: don't BUG on no write file Don't bug if there's no writable files found for page writeback. If ever this is triggered, a WARN_ON helps debugging it much better then a BUG_ON. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: writepage: skip already in flight If ->writepage() tries to write back a page whose copy is still in flight, then just skip by calling redirty_page_for_writepage(). This is OK, since now ->writepage() should never be called for data integrity sync. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: roll back changes if request not found fuse_writepage_in_flight() returns false if it fails to find request with given index in fi->writepages. Then the caller proceeds with populating data->orig_pages[] and incrementing req->num_pages. Hence, fuse_writepage_in_flight() must revert changes it made in request before returning false. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 15:01:07 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: roll back changes if request not found fuse_writepage_in_flight() returns false if it fails to find request with given index in fi->writepages. Then the caller proceeds with populating data->orig_pages[] and incrementing req->num_pages. Hence, fuse_writepage_in_flight() must revert changes it made in request before returning false. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 15:01:07 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: writepages: roll back changes if request not found fuse_writepage_in_flight() returns false if it fails to find request with given index in fi->writepages. Then the caller proceeds with populating data->orig_pages[] and incrementing req->num_pages. Hence, fuse_writepage_in_flight() must revert changes it made in request before returning false. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 15:01:07 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: req state use flags Use flags for representing the state in fuse_req. This is needed since req->list will be protected by different locks in different states, hence we'll want the state itself to be split into distinct bits, each protected with the relevant lock in that state. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:01 +02:00
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info Now that we got rid of the bdi abuse on character devices we can always use sb->s_bdi to get at the backing_dev_info for a file, except for the block device special case. Export inode_to_bdi and replace uses of mapping->backing_dev_info with it to prepare for the removal of mapping->backing_dev_info. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-14 10:42:36 +01:00
fuse: writepages: update bdi writeout when deleting secondary request BDI_WRITTEN counter is used to estimate bdi bandwidth. It must be incremented every time as bdi ends page writeback. No matter whether it was fulfilled by actual write or by discarding the request (e.g. due to shrunk i_size). Note that even before writepages patches, the case "Got truncated off completely" was handled in fuse_send_writepage() by calling fuse_writepage_finish() which updated BDI_WRITTEN unconditionally. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-02 21:38:43 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
mm: move most file-based accounting to the node There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 15:46:20 -07:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: req use bitops Finer grained locking will mean there's no single lock to protect modification of bitfileds in fuse_req. So move to using bitops. Can use the non-atomic variants for those which happen while the request definitely has only one reference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
writeback: move backing_dev_info->bdi_stat[] into bdi_writeback Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback) and the role of the separation is unclear. For cgroup support for writeback IOs, a bdi will be updated to host multiple wb's where each wb serves writeback IOs of a different cgroup on the bdi. To achieve that, a wb should carry all states necessary for servicing writeback IOs for a cgroup independently. This patch moves bdi->bdi_stat[] into wb. * enum bdi_stat_item is renamed to wb_stat_item and the prefix of all enums is changed from BDI_ to WB_. * BDI_STAT_BATCH() -> WB_STAT_BATCH() * [__]{add|inc|dec|sum}_wb_stat(bdi, ...) -> [__]{add|inc}_wb_stat(wb, ...) * bdi_stat[_error]() -> wb_stat[_error]() * bdi_writeout_inc() -> wb_writeout_inc() * stat init is moved to bdi_wb_init() and bdi_wb_exit() is added and frees stat. * As there's still only one bdi_writeback per backing_dev_info, all uses of bdi->stat[] are mechanically replaced with bdi->wb.stat[] introducing no behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-22 17:13:27 -04:00
mm: move most file-based accounting to the node There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 15:46:20 -07:00
fuse: writepages: handle same page rewrites As Maxim Patlasov pointed out, it's possible to get a dirty page while it's copy is still under writeback, despite fuse_page_mkwrite() doing its thing (direct IO). This could result in two concurrent write request for the same offset, with data corruption if they get mixed up. To prevent this, fuse needs to check and delay such writes. This implementation does this by: 1. check if page is still under writeout, if so create a new, single page secondary request for it 2. chain this secondary request onto the in-flight request 2/a. if a seconday request for the same offset was already chained to the in-flight request, then just copy the contents of the page and discard the new secondary request. This makes sure that for each page will have at most two requests associated with it 3. when the in-flight request finished, send off all secondary requests chained onto it Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: replace count*size kzalloc by kcalloc kcalloc manages count*sizeof overflow. Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-06-23 18:35:15 +02:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: fix race in fuse_writepages() The patch fixes a race between ftruncate(2), mmap-ed write and write(2): 1) An user makes a page dirty via mmap-ed write. 2) The user performs shrinking truncate(2) intended to purge the page. 3) Before fuse_do_setattr calls truncate_pagecache, the page goes to writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request, then releases the original page by end_page_writeback and unlock it. 4) fuse_do_setattr completes and successfully returns. Since now, i_mutex is free. 5) Ordinary write(2) extends i_size back to cover the page. Note that fuse_send_write_pages do wait for fuse writeback, but for another page->index. 6) fuse_writepages_fill attaches more pages to the request (if any), then fuse_writepages_send is eventually called. It is supposed to crop inarg->size of the request, but it doesn't because i_size has already been extended back. Moving end_page_writeback behind fuse_writepages_send guarantees that __fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size of the request before write(2) gets the chance to extend i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-08-16 15:51:41 +04:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
assorted conversions to %p[dD] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-21 20:11:25 -04:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
fuse: fix fuse_write_end() if zero bytes were copied If pos is at the beginning of a page and copied is zero then page is not zeroed but is marked uptodate. Fix by skipping everything except unlock/put of page if zero bytes were copied. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Fixes: 6b12c1b37e55 ("fuse: Implement write_begin/write_end callbacks") Cc: <stable@vger.kernel.org> # v3.15+ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-08-18 09:10:44 +02:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
fuse: fix fuse_write_end() if zero bytes were copied If pos is at the beginning of a page and copied is zero then page is not zeroed but is marked uptodate. Fix by skipping everything except unlock/put of page if zero bytes were copied. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Fixes: 6b12c1b37e55 ("fuse: Implement write_begin/write_end callbacks") Cc: <stable@vger.kernel.org> # v3.15+ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-08-18 09:10:44 +02:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 15:29:47 +03:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
mm: page_mkwrite change prototype to match fault Change the page_mkwrite prototype to take a struct vm_fault, and return VM_FAULT_xxx flags. There should be no functional change. This makes it possible to return much more detailed error information to the VM (and also can provide more information eg. virtual_address to the driver, which might be important in some special cases). This is required for a subsequent fix. And will also make it easier to merge page_mkwrite() with fault() in future. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Chris Mason <chris.mason@oracle.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <joel.becker@oracle.com> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Felix Blyakher <felixb@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-31 15:23:21 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
mm: page_mkwrite change prototype to match fault Change the page_mkwrite prototype to take a struct vm_fault, and return VM_FAULT_xxx flags. There should be no functional change. This makes it possible to return much more detailed error information to the VM (and also can provide more information eg. virtual_address to the driver, which might be important in some special cases). This is required for a subsequent fix. And will also make it easier to merge page_mkwrite() with fault() in future. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Chris Mason <chris.mason@oracle.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <joel.becker@oracle.com> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Felix Blyakher <felixb@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-31 15:23:21 -07:00
fuse: lock page in mkwrite Lock the page in fuse_page_mkwrite() to protect against a race with fuse_writepage() where the page is redirtied before the actual writeback begins. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:51 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: lock page in mkwrite Lock the page in fuse_page_mkwrite() to protect against a race with fuse_writepage() where the page is redirtied before the actual writeback begins. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:51 +02:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
const: mark struct vm_struct_operations * mark struct vm_area_struct::vm_ops as const * mark vm_ops in AGP code But leave TTM code alone, something is fishy there with global vm_ops being used. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 22:29:37 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
mm: implement ->map_pages for page cache filemap_map_pages() is generic implementation of ->map_pages() for filesystems who uses page cache. It should be safe to use filemap_map_pages() for ->map_pages() if filesystem use filemap_fault() for ->fault(). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Dave Chinner <david@fromorbit.com> Cc: Ning Qu <quning@gmail.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 15:37:19 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Linking file to inode helper When writeback is ON every writeable file should be in per-inode write list, not only mmap-ed ones. Thus introduce a helper for this linkage. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:10:04 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: allow private mappings of "direct_io" files Allow MAP_PRIVATE mmaps of "direct_io" files. This is necessary for execute support. MAP_SHARED mappings require some sort of coherency between the underlying file and the mapping. With "direct_io" it is difficult to provide this, so for the moment just disallow shared (read-write and read-only) mappings altogether. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:35 +02:00
fuse: fix "direct_io" private mmap MAP_PRIVATE mmap could return stale data from the cache for "direct_io" files. Fix this by flushing the cache on mmap. Found with a slightly modified fsx-linux. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-09 17:37:53 +02:00
fuse: allow private mappings of "direct_io" files Allow MAP_PRIVATE mmaps of "direct_io" files. This is necessary for execute support. MAP_SHARED mappings require some sort of coherency between the underlying file and the mapping. With "direct_io" it is difficult to provide this, so for the moment just disallow shared (read-write and read-only) mappings altogether. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:35 +02:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
[PATCH] fuse: scramble lock owner ID VFS uses current->files pointer as lock owner ID, and it wouldn't be prudent to expose this value to userspace. So scramble it with XTEA using a per connection random key, known only to the kernel. Only one direction needs to be implemented, since the ID is never sent in the reverse direction. The XTEA algorithm is implemented inline since it's simple enough to do so, and this adds less complexity than if the crypto API were used. Thanks to Jesper Juhl for the idea. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:55 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
locks: rename lock-manager ops Both the filesystem and the lock manager can associate operations with a lock. Confusingly, one of them (fl_release_private) actually has the same name in both operation structures. It would save some confusion to give the lock-manager ops different names. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-07-20 20:21:59 -04:00
fuse: lockd support If fuse filesystem doesn't define it's own lock operations, then allow the lock manager to work with fuse. Adding lockd support for remote locking is also possible, but more rarely used, so leave it till later. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:49:02 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
[PATCH] fuse: add request interruption Add synchronous request interruption. This is needed for file locking operations which have to be interruptible. However filesystem may implement interruptibility of other operations (e.g. like NFS 'intr' mount option). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:54 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: lockd support If fuse filesystem doesn't define it's own lock operations, then allow the lock manager to work with fuse. Adding lockd support for remote locking is also possible, but more rarely used, so leave it till later. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:49:02 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
locks: give posix_test_lock same interface as ->lock posix_test_lock() and ->lock() do the same job but have gratuitously different interfaces. Modify posix_test_lock() so the two agree, simplifying some code in the process. Signed-off-by: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
2007-02-21 00:55:18 -05:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: lockd support If fuse filesystem doesn't define it's own lock operations, then allow the lock manager to work with fuse. Adding lockd support for remote locking is also possible, but more rarely used, so leave it till later. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Matthew Wilcox <matthew@wil.cx> Cc: David Teigland <teigland@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 01:49:02 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: fix flock Commit a9ff4f87 "fuse: support BSD locking semantics" overlooked a number of issues with supporing flock locks over existing POSIX locking infrastructure: - it's not backward compatible, passing flock(2) calls to userspace unconditionally (if userspace sets FUSE_POSIX_LOCKS) - it doesn't cater for the fact that flock locks are automatically unlocked on file release - it doesn't take into account the fact that flock exclusive locks (write locks) don't need an fd opened for write. The last one invalidates the original premise of the patch that flock locks can be emulated with POSIX locks. This patch fixes the first two issues. The last one needs to be fixed in userspace if the filesystem assumed that a write lock will happen only on a file operned for write (as in the case of the current fuse library). Reported-by: Sebastian Pipping <webmaster@hartwork.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
Move locks API users to locks_lock_inode_wait() Instead of having users check for FL_POSIX or FL_FLOCK to call the correct locks API function, use the check within locks_lock_inode_wait(). This allows for some later cleanup. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
2015-10-22 13:38:14 -04:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: fix flock Commit a9ff4f87 "fuse: support BSD locking semantics" overlooked a number of issues with supporing flock locks over existing POSIX locking infrastructure: - it's not backward compatible, passing flock(2) calls to userspace unconditionally (if userspace sets FUSE_POSIX_LOCKS) - it doesn't cater for the fact that flock locks are automatically unlocked on file release - it doesn't take into account the fact that flock exclusive locks (write locks) don't need an fd opened for write. The last one invalidates the original premise of the patch that flock locks can be emulated with POSIX locks. This patch fixes the first two issues. The last one needs to be fixed in userspace if the filesystem assumed that a write lock will happen only on a file operned for write (as in the case of the current fuse library). Reported-by: Sebastian Pipping <webmaster@hartwork.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: fix flock Commit a9ff4f87 "fuse: support BSD locking semantics" overlooked a number of issues with supporing flock locks over existing POSIX locking infrastructure: - it's not backward compatible, passing flock(2) calls to userspace unconditionally (if userspace sets FUSE_POSIX_LOCKS) - it doesn't cater for the fact that flock locks are automatically unlocked on file release - it doesn't take into account the fact that flock exclusive locks (write locks) don't need an fd opened for write. The last one invalidates the original premise of the patch that flock locks can be emulated with POSIX locks. This patch fixes the first two issues. The last one needs to be fixed in userspace if the filesystem assumed that a write lock will happen only on a file operned for write (as in the case of the current fuse library). Reported-by: Sebastian Pipping <webmaster@hartwork.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
[PATCH] fuse: add bmap support Add support for the BMAP operation for block device based filesystems. This is needed to support swap-files and lilo. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 20:35:51 -08:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add bmap support Add support for the BMAP operation for block device based filesystems. This is needed to support swap-files and lilo. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 20:35:51 -08:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
[PATCH] fuse: add bmap support Add support for the BMAP operation for block device based filesystems. This is needed to support swap-files and lilo. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 20:35:51 -08:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
lseek: the "whence" argument is called "whence" But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 15:59:39 -08:00
fuse: fix race in llseek Fuse doesn't use i_mutex to protect setting i_size, and so generic_file_llseek() can be racy: it doesn't use i_size_read(). So do a fuse specific llseek method, which does use i_size_read(). [akpm@linux-foundation.org: make `retval' loff_t] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:45 -07:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
fuse: fix race in llseek Fuse doesn't use i_mutex to protect setting i_size, and so generic_file_llseek() can be racy: it doesn't use i_size_read(). So do a fuse specific llseek method, which does use i_size_read(). [akpm@linux-foundation.org: make `retval' loff_t] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:45 -07:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
lseek: the "whence" argument is called "whence" But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 15:59:39 -08:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: add support for SEEK_HOLE and SEEK_DATA in lseek A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
2015-06-30 23:40:22 +05:30
fuse: llseek optimize SEEK_CUR and SEEK_SET Use generic_file_llseek() instead of open coding the seek function. i_mutex protection is only necessary for SEEK_END (and SEEK_HOLE, SEEK_DATA), so move SEEK_CUR and SEEK_SET out from under i_mutex. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:48 +01:00
fuse: fix race in llseek Fuse doesn't use i_mutex to protect setting i_size, and so generic_file_llseek() can be racy: it doesn't use i_size_read(). So do a fuse specific llseek method, which does use i_size_read(). [akpm@linux-foundation.org: make `retval' loff_t] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:45 -07:00
fuse: fix ioctl when server is 32bit If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: fix ioctl ABI In kernel ABI version 7.16 and later FUSE_IOCTL_RETRY reply from a unrestricted IOCTL request shall return with an array of 'struct fuse_ioctl_iovec' instead of 'struct iovec'. This fixes the ABI ambiguity of 32bit vs. 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: fix ioctl when server is 32bit If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: verify ioctl retries Verify that the total length of the iovec returned in FUSE_IOCTL_RETRY doesn't overflow iov_length(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: verify all ioctl retry iov elements Commit 7572777eef78ebdee1ecb7c258c0ef94d35bad16 attempted to verify that the total iovec from the client doesn't overflow iov_length() but it only checked the first element. The iovec could still overflow by starting with a small element. The obvious fix is to check all the elements. The overflow case doesn't look dangerous to the kernel as the copy is limited by the length after the overflow. This fix restores the intention of returning an error instead of successfully copying less than the iovec represented. I found this by code inspection. I built it but don't have a test case. I'm cc:ing stable because the initial commit did as well. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: <stable@vger.kernel.org> [2.6.37+]
2012-07-24 12:10:11 -07:00
fuse: verify ioctl retries Verify that the total length of the iovec returned in FUSE_IOCTL_RETRY doesn't overflow iov_length(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: fix ioctl ABI In kernel ABI version 7.16 and later FUSE_IOCTL_RETRY reply from a unrestricted IOCTL request shall return with an array of 'struct fuse_ioctl_iovec' instead of 'struct iovec'. This fixes the ABI ambiguity of 32bit vs. 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use inode in fuse_do_ioctl() helper Create a helper for sending an IOCTL request that doesn't use a struct inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use fuse_ioctl_copy_user() helper The two invocations share little code. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: fix ioctl ABI In kernel ABI version 7.16 and later FUSE_IOCTL_RETRY reply from a unrestricted IOCTL request shall return with an array of 'struct fuse_ioctl_iovec' instead of 'struct iovec'. This fixes the ABI ambiguity of 32bit vs. 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: fix ioctl ABI In kernel ABI version 7.16 and later FUSE_IOCTL_RETRY reply from a unrestricted IOCTL request shall return with an array of 'struct fuse_ioctl_iovec' instead of 'struct iovec'. This fixes the ABI ambiguity of 32bit vs. 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: Use kcalloc instead of kzalloc to allocate array The advantage of kcalloc is, that will prevent integer overflows which could result from the multiplication of number of elements and size and it is also a bit nicer to read. The semantic patch that makes this change is available in https://lkml.org/lkml/2011/11/25/107 Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-11-29 22:08:00 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: fix sparse warning in ioctl Fix sparse warning: CHECK fs/fuse/file.c fs/fuse/file.c:1615:17: warning: incorrect type in assignment (different address spaces) fs/fuse/file.c:1615:17: expected void [noderef] <asn:1>*iov_base fs/fuse/file.c:1615:17: got void *<noident> This was introduced by "fuse: implement ioctl support". Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-12-02 14:49:42 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: rework fuse_do_ioctl() fuse_do_ioctl() already calculates the number of pages it's going to use. It is stored in 'num_pages' variable. So the patch simply uses it for allocating fuse_req. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:49:13 +04:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: optimize fuse_get_user_pages() Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as possible. This is very beneficial in case of iov[] consisting of many iov-s of relatively small sizes (e.g. PAGE_SIZE). Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-10-26 19:50:29 +04:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use inode in fuse_do_ioctl() helper Create a helper for sending an IOCTL request that doesn't use a struct inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use fuse_ioctl_copy_user() helper The two invocations share little code. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: add fuse_ prefix to several functions Add fuse_ prefix to request_send*() and get_root_inode() as some of those functions will be exported for CUSE. With or without CUSE export, having the function names scoped is a good idea for debuggability. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: remove the second argument of k[un]map_atomic() Signed-off-by: Cong Wang <amwang@redhat.com>
2011-11-25 23:14:30 +08:00
fuse: fix ioctl ABI In kernel ABI version 7.16 and later FUSE_IOCTL_RETRY reply from a unrestricted IOCTL request shall return with an array of 'struct fuse_ioctl_iovec' instead of 'struct iovec'. This fixes the ABI ambiguity of 32bit vs. 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: fix ioctl when server is 32bit If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: remove the second argument of k[un]map_atomic() Signed-off-by: Cong Wang <amwang@redhat.com>
2011-11-25 23:14:30 +08:00
fuse: fix ioctl when server is 32bit If a 32bit CUSE server is run on 64bit this results in EIO being returned to the caller. The reason is that FUSE_IOCTL_RETRY reply was defined to use 'struct iovec', which is different on 32bit and 64bit archs. Work around this by looking at the size of the reply to determine which struct was used. This is only needed if CONFIG_COMPAT is defined. A more permanent fix for the interface will be to use the same struct on both 32bit and 64bit. Reported-by: "ccmail111" <ccmail111@yahoo.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: verify ioctl retries Verify that the total length of the iovec returned in FUSE_IOCTL_RETRY doesn't overflow iov_length(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org> CC: <stable@kernel.org> [2.6.31+]
2010-11-30 16:39:27 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use fuse_ioctl_copy_user() helper The two invocations share little code. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-10-01 07:32:33 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: ioctl cleanup Get rid of unnecessary page_address()-es. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Tejun Heo <tj@kernel.org>
2010-12-07 20:16:56 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: support ioctl on directories Multiplexing filesystems may want to support ioctls on the underlying files and directores (e.g. FS_IOC_{GET,SET}FLAGS). Ioctl support on directories was missing so add it now. Reported-by: Antonio SJ Musumeci <bile@landofbile.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
fuse: don't use inode in fuse_do_ioctl() helper Create a helper for sending an IOCTL request that doesn't use a struct inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
more file_inode() open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
fuse: don't use inode in fuse_do_ioctl() helper Create a helper for sending an IOCTL request that doesn't use a struct inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
Do not use RCU for current process credentials Commit c69e8d9c0 added rcu lock to fuse/dir.c It was assuming that 'task' is some other process but in fact this parameter always equals to 'current'. Inline this parameter to make it more readable and remove RCU lock as it is not needed when access current process credentials. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-14 22:30:00 -08:00
fuse: don't use inode in fuse_do_ioctl() helper Create a helper for sending an IOCTL request that doesn't use a struct inode. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: support ioctl on directories Multiplexing filesystems may want to support ioctls on the underlying files and directores (e.g. FS_IOC_{GET,SET}FLAGS). Ioctl support on directories was missing so add it now. Reported-by: Antonio SJ Musumeci <bile@landofbile.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: support ioctl on directories Multiplexing filesystems may want to support ioctls on the underlying files and directores (e.g. FS_IOC_{GET,SET}FLAGS). Ioctl support on directories was missing so add it now. Reported-by: Antonio SJ Musumeci <bile@landofbile.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: fix "uninitialized variable" warning Fix the following warning: In file included from include/linux/fs.h:16:0, from fs/fuse/fuse_i.h:13, from fs/fuse/file.c:9: fs/fuse/file.c: In function 'fuse_file_poll': include/linux/rbtree.h:82:28: warning: 'parent' may be used uninitialized in this function [-Wmaybe-uninitialized] fs/fuse/file.c:2592:27: note: 'parent' was declared here Signed-off-by: Rajat Jain <rajatxjain@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-02-05 15:24:57 -08:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: don't use inode in fuse_file_poll Use ff->fc and ff->nodeid instead of file->f_dentry->d_inode in the fuse_file_poll() implementation. This prepares this function for use by CUSE, where the inode is not owned by a fuse filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:41 +02:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: send poll events commit 626cf23660 "poll: add poll_requested_events()..." enabled us to send the requested events to the filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-02-04 16:14:32 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: export symbols to be used by CUSE Export the following symbols for CUSE. fuse_conn_put() fuse_conn_get() fuse_conn_kill() fuse_send_init() fuse_do_open() fuse_sync_release() fuse_direct_io() fuse_do_ioctl() fuse_file_poll() fuse_request_alloc() fuse_get_req() fuse_put_request() fuse_request_send() fuse_abort_conn() fuse_dev_release() fuse_dev_operations Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-14 10:54:53 +09:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: truncate file if async dio failed The patch improves error handling in fuse_direct_IO(): if we successfully submitted several fuse requests on behalf of synchronous direct write extending file and some of them failed, let's try to do our best to clean-up. Changed in v2: reuse fuse_do_setattr(). Thanks to Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-18 14:05:08 +04:00
fuse: Propagate dentry down to inode_change_ok() To avoid clearing of capabilities or security related extended attributes too early, inode_change_ok() will need to take dentry instead of inode. Propagate it down to fuse_do_setattr(). Acked-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2016-05-26 17:12:41 +02:00
fuse: truncate file if async dio failed The patch improves error handling in fuse_direct_IO(): if we successfully submitted several fuse requests on behalf of synchronous direct write extending file and some of them failed, let's try to do our best to clean-up. Changed in v2: reuse fuse_do_setattr(). Thanks to Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-18 14:05:08 +04:00
fuse: fix alignment in short read optimization for async_dio The bug was introduced with async_dio feature: trying to optimize short reads, we cut number-of-bytes-to-read to i_size boundary. Hence the following example: truncate --size=300 /mnt/file dd if=/mnt/file of=/dev/null iflag=direct led to FUSE_READ request of 300 bytes size. This turned out to be problem for userspace fuse implementations who rely on assumption that kernel fuse does not change alignment of request from client FS. The patch turns off the optimization if async_dio is disabled. And, if it's enabled, the patch fixes adjustment of number-of-bytes-to-read to preserve alignment. Note, that we cannot throw out short read optimization entirely because otherwise a direct read of a huge size issued on a tiny file would generate a huge amount of fuse requests and most of them would be ACKed by userspace with zero bytes read. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-30 16:41:34 +04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
direct-io: eliminate the offset argument to ->direct_IO Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually work, so eliminate the superflous argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-07 08:51:58 -07:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: add flag to turn on async direct IO Without async DIO write requests to a single file were always serialized. With async DIO that's no longer the case. So don't turn on async DIO by default for fear of breaking backward compatibility. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-01 14:37:21 +02:00
fuse: fix alignment in short read optimization for async_dio The bug was introduced with async_dio feature: trying to optimize short reads, we cut number-of-bytes-to-read to i_size boundary. Hence the following example: truncate --size=300 /mnt/file dd if=/mnt/file of=/dev/null iflag=direct led to FUSE_READ request of 300 bytes size. This turned out to be problem for userspace fuse implementations who rely on assumption that kernel fuse does not change alignment of request from client FS. The patch turns off the optimization if async_dio is disabled. And, if it's enabled, the patch fixes adjustment of number-of-bytes-to-read to preserve alignment. Note, that we cannot throw out short read optimization entirely because otherwise a direct read of a huge size issued on a tiny file would generate a huge amount of fuse requests and most of them would be ACKed by userspace with zero bytes read. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-30 16:41:34 +04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
get rid of pointless iov_length() in ->direct_IO() all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-04 22:38:00 -05:00
direct-io: eliminate the offset argument to ->direct_IO Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually work, so eliminate the superflous argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-07 08:51:58 -07:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
direct_IO: use iov_iter_rw() instead of rw everywhere The rw parameter to direct_IO is redundant with iov_iter->type, and treated slightly differently just about everywhere it's used: some users do rw & WRITE, and others do rw == WRITE where they should be doing a bitwise check. Simplify this with the new iov_iter_rw() helper, which always returns either READ or WRITE. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-16 04:33:52 -07:00
Fix race when checking i_size on direct i/o read So far I've had one ACK for this, and no other comments. So I think it is probably time to send this via some suitable tree. I'm guessing that the vfs tree would be the most appropriate route, but not sure that there is one at the moment (don't see anything recent at kernel.org) so in that case I think -mm is the "back up plan". Al, please let me know if you will take this? Steve. --------------------- Following on from the "Re: [PATCH v3] vfs: fix a bug when we do some dio reads with append dio writes" thread on linux-fsdevel, this patch is my current version of the fix proposed as option (b) in that thread. Removing the i_size test from the direct i/o read path at vfs level means that filesystems now have to deal with requests which are beyond i_size themselves. These I've divided into three sets: a) Those with "no op" ->direct_IO (9p, cifs, ceph) These are obviously not going to be an issue b) Those with "home brew" ->direct_IO (nfs, fuse) I've been told that NFS should not have any problem with the larger i_size, however I've added an extra test to FUSE to duplicate the original behaviour just to be on the safe side. c) Those using __blockdev_direct_IO() These call through to ->get_block() which should deal with the EOF condition correctly. I've verified that with GFS2 and I believe that Zheng has verified it for ext4. I've also run the test on XFS and it passes both before and after this change. The part of the patch in filemap.c looks a lot larger than it really is - there are only two lines of real change. The rest is just indentation of the contained code. There remains a test of i_size though, which was added for btrfs. It doesn't cause the other filesystems a problem as the test is performed after ->direct_IO has been called. It is possible that there is a race that does matter to btrfs, however this patch doesn't change that, so its still an overall improvement. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Reported-by: Zheng Liu <gnehzuil.liu@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-01-24 14:42:22 +00:00
fuse: optimize short direct reads If user requested direct read beyond EOF, we can skip sending fuse requests for positions beyond EOF because userspace would ACK them with zero bytes read anyway. We can trust to i_size in fuse_direct_IO for such cases because it's called from fuse_file_aio_read() and the latter updates fuse attributes including i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:26 +04:00
direct_IO: use iov_iter_rw() instead of rw everywhere The rw parameter to direct_IO is redundant with iov_iter->type, and treated slightly differently just about everywhere it's used: some users do rw & WRITE, and others do rw == WRITE where they should be doing a bitwise check. Simplify this with the new iov_iter_rw() helper, which always returns either READ or WRITE. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-16 04:33:52 -07:00
fuse: optimize short direct reads If user requested direct read beyond EOF, we can skip sending fuse requests for positions beyond EOF because userspace would ACK them with zero bytes read anyway. We can trust to i_size in fuse_direct_IO for such cases because it's called from fuse_file_aio_read() and the latter updates fuse attributes including i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:26 +04:00
fuse: ->direct_IO() doesn't need generic_write_checks() already done by caller. We used to call __fuse_direct_write(), which called generic_write_checks(); now the former got expanded, bringing the latter to the surface. It used to be called all along and calling it from there had been wrong all along... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-07 15:06:19 -04:00
fuse: optimize short direct reads If user requested direct read beyond EOF, we can skip sending fuse requests for positions beyond EOF because userspace would ACK them with zero bytes read anyway. We can trust to i_size in fuse_direct_IO for such cases because it's called from fuse_file_aio_read() and the latter updates fuse attributes including i_size. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:26 +04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
direct_IO: use iov_iter_rw() instead of rw everywhere The rw parameter to direct_IO is redundant with iov_iter->type, and treated slightly differently just about everywhere it's used: some users do rw & WRITE, and others do rw == WRITE where they should be doing a bitwise check. Simplify this with the new iov_iter_rw() helper, which always returns either READ or WRITE. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-16 04:33:52 -07:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: add flag to turn on async direct IO Without async DIO write requests to a single file were always serialized. With async DIO that's no longer the case. So don't turn on async DIO by default for fear of breaking backward compatibility. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-01 14:37:21 +02:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: fix alignment in short read optimization for async_dio The bug was introduced with async_dio feature: trying to optimize short reads, we cut number-of-bytes-to-read to i_size boundary. Hence the following example: truncate --size=300 /mnt/file dd if=/mnt/file of=/dev/null iflag=direct led to FUSE_READ request of 300 bytes size. This turned out to be problem for userspace fuse implementations who rely on assumption that kernel fuse does not change alignment of request from client FS. The patch turns off the optimization if async_dio is disabled. And, if it's enabled, the patch fixes adjustment of number-of-bytes-to-read to preserve alignment. Note, that we cannot throw out short read optimization entirely because otherwise a direct read of a huge size issued on a tiny file would generate a huge amount of fuse requests and most of them would be ACKed by userspace with zero bytes read. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-30 16:41:34 +04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
direct_IO: use iov_iter_rw() instead of rw everywhere The rw parameter to direct_IO is redundant with iov_iter->type, and treated slightly differently just about everywhere it's used: some users do rw & WRITE, and others do rw == WRITE where they should be doing a bitwise check. Simplify this with the new iov_iter_rw() helper, which always returns either READ or WRITE. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-16 04:33:52 -07:00
fuse: ->direct_IO() doesn't need generic_write_checks() already done by caller. We used to call __fuse_direct_write(), which called generic_write_checks(); now the former got expanded, bringing the latter to the surface. It used to be called all along and calling it from there had been wrong all along... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-07 15:06:19 -04:00
expand __fuse_direct_write() in both callers it's actually shorter that way *and* later we'll want iocb in scope of generic_write_check() caller. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:15:58 -04:00
fuse: pull iov_iter initializations up ... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-16 15:50:47 -04:00
expand __fuse_direct_write() in both callers it's actually shorter that way *and* later we'll want iocb in scope of generic_write_check() caller. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:15:58 -04:00
fuse: make fuse_direct_io() aware about AIO The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:20:51 +04:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: improve aio directIO write performance for size extending writes While sending the blocking directIO in fuse, the write request is broken into sub-requests, each of default size 128k and all the requests are sent in non-blocking background mode if async_dio mode is supported by libfuse. The process which issue the write wait for the completion of all the sub-requests. Sending multiple requests parallely gives a chance to perform parallel writes in the user space fuse implementation if it is multi-threaded and hence improves the performance. When there is a size extending aio dio write, we switch to blocking mode so that we can properly update the size of the file after completion of the writes. However, in this situation all the sub-requests are sent in serialized manner where the next request is sent only after receiving the reply of the current request. Hence the multi-threaded user space implementation is not utilized properly. This patch changes the size extending aio dio behavior to exactly follow blocking dio. For multi threaded fuse implementation having 10 threads and using buffer size of 64MB to perform async directIO, we are getting double the speed. Signed-off-by: Ashish Sangwan <ashishsangwan2@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-04-07 17:18:11 +05:30
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
fuse: enable asynchronous processing direct IO In case of synchronous DIO request (i.e. read(2) or write(2) for a file opened with O_DIRECT), the patch submits fuse requests asynchronously, but waits for their completions before return from fuse_direct_IO(). In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened with O_DIRECT), the patch submits fuse requests asynchronously and return -EIOCBQUEUED immediately. The only special case is async DIO extending file. Here the patch falls back to old behaviour because we can't return -EIOCBQUEUED and update i_size later, without i_mutex hold. And we have no method to wait on real async I/O requests. The patch also clean __fuse_direct_write() up: it's better to update i_size in its callers. Thanks Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-14 19:21:08 +04:00
fuse: Add reference counting for fuse_io_priv The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-11 10:35:34 -06:00
fuse: handle synchronous iocbs internally Based on a patch from Maxim Patlasov <MPatlasov@parallels.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-02 14:59:43 +01:00
direct_IO: use iov_iter_rw() instead of rw everywhere The rw parameter to direct_IO is redundant with iov_iter->type, and treated slightly differently just about everywhere it's used: some users do rw & WRITE, and others do rw == WRITE where they should be doing a bitwise check. Simplify this with the new iov_iter_rw() helper, which always returns either READ or WRITE. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-16 04:33:52 -07:00
fuse: truncate file if async dio failed The patch improves error handling in fuse_direct_IO(): if we successfully submitted several fuse requests on behalf of synchronous direct write extending file and some of them failed, let's try to do our best to clean-up. Changed in v2: reuse fuse_do_setattr(). Thanks to Brian for suggestion. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-12-18 14:05:08 +04:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: make fuse_file_fallocate() static Fix the following sparse warning: fs/fuse/file.c:2249:6: warning: symbol 'fuse_file_fallocate' was not declared. Should it be static? Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-11-10 16:55:56 +01:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
fuse: use file_inode() in fuse_file_fallocate() Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 10:04:51 +01:00
fuse: fix fallocate vs. ftruncate race A former patch introducing FUSE_I_SIZE_UNSTABLE flag provided detailed description of races between ftruncate and anyone who can extend i_size: > 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size > changed (due to our own fuse_do_setattr()) and is going to call > truncate_pagecache() for some 'new_size' it believes valid right now. But by > the time that particular truncate_pagecache() is called ... > 2. fuse_do_setattr() returns (either having called truncate_pagecache() or > not -- it doesn't matter). > 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). > 4. mmap-ed write makes a page in the extended region dirty. This patch adds necessary bits to fuse_file_fallocate() to protect from that race. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-09-13 19:20:16 +04:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
fuse: hold i_mutex in fuse_file_fallocate() Changing size of a file on server and local update (fuse_write_update_size) should be always protected by inode->i_mutex. Otherwise a race like this is possible: 1. Process 'A' calls fallocate(2) to extend file (~FALLOC_FL_KEEP_SIZE). fuse_file_fallocate() sends FUSE_FALLOCATE request to the server. 2. Process 'B' calls ftruncate(2) shrinking the file. fuse_do_setattr() sends shrinking FUSE_SETATTR request to the server and updates local i_size by i_size_write(inode, outarg.attr.size). 3. Process 'A' resumes execution of fuse_file_fallocate() and calls fuse_write_update_size(inode, offset + length). But 'offset + length' was obsoleted by ftruncate from previous step. Changed in v2 (thanks Brian and Anand for suggestions): - made relation between mutex_lock() and fuse_set_nowrite(inode) more explicit and clear. - updated patch description to use ftruncate(2) in example Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-13 12:16:39 +04:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
fuse: check fallocate mode Don't allow new fallocate modes until we figure out what (if anything) that takes. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:21 +02:00
fuse: optimize fallocate on permanent failure If userspace filesystem doesn't support fallocate, remember this and don't send request next time. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-26 10:56:36 +02:00
fuse: hold i_mutex in fuse_file_fallocate() Changing size of a file on server and local update (fuse_write_update_size) should be always protected by inode->i_mutex. Otherwise a race like this is possible: 1. Process 'A' calls fallocate(2) to extend file (~FALLOC_FL_KEEP_SIZE). fuse_file_fallocate() sends FUSE_FALLOCATE request to the server. 2. Process 'B' calls ftruncate(2) shrinking the file. fuse_do_setattr() sends shrinking FUSE_SETATTR request to the server and updates local i_size by i_size_write(inode, outarg.attr.size). 3. Process 'A' resumes execution of fuse_file_fallocate() and calls fuse_write_update_size(inode, offset + length). But 'offset + length' was obsoleted by ftruncate from previous step. Changed in v2 (thanks Brian and Anand for suggestions): - made relation between mutex_lock() and fuse_set_nowrite(inode) more explicit and clear. - updated patch description to use ftruncate(2) in example Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-13 12:16:39 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: wait for writeback in fuse_file_fallocate() The patch fixes a race between mmap-ed write and fallocate(PUNCH_HOLE): 1) An user makes a page dirty via mmap-ed write. 2) The user performs fallocate(2) with mode == PUNCH_HOLE|KEEP_SIZE and <offset, size> covering the page. 3) Before truncate_pagecache_range call from fuse_file_fallocate, the page goes to write-back. The page is fully processed by fuse_writepage (including end_page_writeback on the page), but fuse_flush_writepages did nothing because fi->writectr < 0. 4) truncate_pagecache_range is called and fuse_file_fallocate is finishing by calling fuse_release_nowrite. The latter triggers processing queued write-back request which will write stale data to the hole soon. Changed in v2 (thanks to Brian for suggestion): - Do not truncate page cache until FUSE_FALLOCATE succeeded. Otherwise, we can end up in returning -ENOTSUPP while user data is already punched from page cache. Use filemap_write_and_wait_range() instead. Changed in v3 (thanks to Miklos for suggestion): - fuse_wait_on_writeback() is prone to livelocks; use fuse_set_nowrite() instead. So far as we need a dirty-page barrier only, fuse_sync_writes() should be enough. - rebased to for-linus branch of fuse.git Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-09-13 19:19:54 +04:00
fuse: truncate pagecache range on hole punch fuse supports hole punch via the fallocate() FALLOC_FL_PUNCH_HOLE interface. When a hole punch is passed through, the page cache is not cleared and thus allows reading stale data from the cache. This is easily demonstrable (using FOPEN_KEEP_CACHE) by reading a smallish random data file into cache, punching a hole and creating a copy of the file. Drop caches or remount and observe that the original file no longer matches the file copied after the hole punch. The original file contains a zeroed range and the latter file contains stale data. Protect against writepage requests in progress and punch out the associated page cache range after a successful client fs hole punch. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 09:30:32 -04:00
fuse: fix fallocate vs. ftruncate race A former patch introducing FUSE_I_SIZE_UNSTABLE flag provided detailed description of races between ftruncate and anyone who can extend i_size: > 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size > changed (due to our own fuse_do_setattr()) and is going to call > truncate_pagecache() for some 'new_size' it believes valid right now. But by > the time that particular truncate_pagecache() is called ... > 2. fuse_do_setattr() returns (either having called truncate_pagecache() or > not -- it doesn't matter). > 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). > 4. mmap-ed write makes a page in the extended region dirty. This patch adds necessary bits to fuse_file_fallocate() to protect from that race. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-09-13 19:20:16 +04:00
fuse: introduce fuse_simple_request() helper The following pattern is repeated many times: req = fuse_get_req_nopages(fc); /* Initialize req->(in|out).args */ fuse_request_send(fc, req); err = req->out.h.error; fuse_put_request(req); Create a new replacement helper: /* Initialize args */ err = fuse_simple_request(fc, &args); In addition to reducing the code size, this will ease moving from the complex arg-based to a simpler page-based I/O on the fuse device. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-12-12 09:49:05 +01:00
fuse: optimize fallocate on permanent failure If userspace filesystem doesn't support fallocate, remember this and don't send request next time. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-26 10:56:36 +02:00
fuse: update inode size and invalidate attributes on fallocate An fallocate request without FALLOC_FL_KEEP_SIZE set can extend the size of a file. Update the inode size after a successful fallocate. Also invalidate the inode attributes after a successful fallocate to ensure we pick up the latest attribute values (i.e., i_blocks). Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 15:27:34 -04:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: fuse: fallocate: use file_update_time() in preparation for getting rid of FUSE_I_MTIME_DIRTY. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-28 14:19:22 +02:00
fuse: Trust kernel i_mtime only Let the kernel maintain i_mtime locally: - clear S_NOCMTIME - implement i_op->update_time() - flush mtime on fsync and last close - update i_mtime explicitly on truncate and fallocate Fuse inode flag FUSE_I_MTIME_DIRTY serves as indication that local i_mtime should be flushed to the server eventually. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-12-26 19:51:11 +04:00
fuse: update inode size and invalidate attributes on fallocate An fallocate request without FALLOC_FL_KEEP_SIZE set can extend the size of a file. Update the inode size after a successful fallocate. Also invalidate the inode attributes after a successful fallocate to ensure we pick up the latest attribute values (i.e., i_blocks). Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 15:27:34 -04:00
fuse: truncate pagecache range on hole punch fuse supports hole punch via the fallocate() FALLOC_FL_PUNCH_HOLE interface. When a hole punch is passed through, the page cache is not cleared and thus allows reading stale data from the cache. This is easily demonstrable (using FOPEN_KEEP_CACHE) by reading a smallish random data file into cache, punching a hole and creating a copy of the file. Drop caches or remount and observe that the original file no longer matches the file copied after the hole punch. The original file contains a zeroed range and the latter file contains stale data. Protect against writepage requests in progress and punch out the associated page cache range after a successful client fs hole punch. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 09:30:32 -04:00
fuse: fix fallocate vs. ftruncate race A former patch introducing FUSE_I_SIZE_UNSTABLE flag provided detailed description of races between ftruncate and anyone who can extend i_size: > 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size > changed (due to our own fuse_do_setattr()) and is going to call > truncate_pagecache() for some 'new_size' it believes valid right now. But by > the time that particular truncate_pagecache() is called ... > 2. fuse_do_setattr() returns (either having called truncate_pagecache() or > not -- it doesn't matter). > 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2). > 4. mmap-ed write makes a page in the extended region dirty. This patch adds necessary bits to fuse_file_fallocate() to protect from that race. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-09-13 19:20:16 +04:00
fuse: wait for writeback in fuse_file_fallocate() The patch fixes a race between mmap-ed write and fallocate(PUNCH_HOLE): 1) An user makes a page dirty via mmap-ed write. 2) The user performs fallocate(2) with mode == PUNCH_HOLE|KEEP_SIZE and <offset, size> covering the page. 3) Before truncate_pagecache_range call from fuse_file_fallocate, the page goes to write-back. The page is fully processed by fuse_writepage (including end_page_writeback on the page), but fuse_flush_writepages did nothing because fi->writectr < 0. 4) truncate_pagecache_range is called and fuse_file_fallocate is finishing by calling fuse_release_nowrite. The latter triggers processing queued write-back request which will write stale data to the hole soon. Changed in v2 (thanks to Brian for suggestion): - Do not truncate page cache until FUSE_FALLOCATE succeeded. Otherwise, we can end up in returning -ENOTSUPP while user data is already punched from page cache. Use filemap_write_and_wait_range() instead. Changed in v3 (thanks to Miklos for suggestion): - fuse_wait_on_writeback() is prone to livelocks; use fuse_set_nowrite() instead. So far as we need a dirty-page barrier only, fuse_sync_writes() should be enough. - rebased to for-linus branch of fuse.git Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: stable@vger.kernel.org
2013-09-13 19:19:54 +04:00
wrappers for ->i_mutex access parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 15:40:57 -05:00
fuse: truncate pagecache range on hole punch fuse supports hole punch via the fallocate() FALLOC_FL_PUNCH_HOLE interface. When a hole punch is passed through, the page cache is not cleared and thus allows reading stale data from the cache. This is easily demonstrable (using FOPEN_KEEP_CACHE) by reading a smallish random data file into cache, punching a hole and creating a copy of the file. Drop caches or remount and observe that the original file no longer matches the file copied after the hole punch. The original file contains a zeroed range and the latter file contains stale data. Protect against writepage requests in progress and punch out the associated page cache range after a successful client fs hole punch. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-17 09:30:32 -04:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 01:56:42 -08:00
fuse: fix race in llseek Fuse doesn't use i_mutex to protect setting i_size, and so generic_file_llseek() can be racy: it doesn't use i_size_read(). So do a fuse specific llseek method, which does use i_size_read(). [akpm@linux-foundation.org: make `retval' loff_t] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:45 -07:00
fuse_file_aio_read(): convert to ->read_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-02 14:47:09 -04:00
fuse: switch to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-03 14:33:23 -04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
sendfile: remove .sendfile from filesystems that use generic_file_sendfile() They can use generic_file_splice_read() instead. Since sys_sendfile() now prefers that, there should be no change in behaviour. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-06-01 11:49:19 +02:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 01:56:42 -08:00
fuse: fix race in llseek Fuse doesn't use i_mutex to protect setting i_size, and so generic_file_llseek() can be racy: it doesn't use i_size_read(). So do a fuse specific llseek method, which does use i_size_read(). [akpm@linux-foundation.org: make `retval' loff_t] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:45 -07:00
fuse: switch fuse_direct_io_file_operations to ->{read,write}_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-30 22:08:36 -04:00
fuse: allow private mappings of "direct_io" files Allow MAP_PRIVATE mmaps of "direct_io" files. This is necessary for execute support. MAP_SHARED mappings require some sort of coherency between the underlying file and the mapping. With "direct_io" it is difficult to provide this, so for the moment just disallow shared (read-write and read-only) mappings altogether. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:35 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
[PATCH] fuse: add POSIX file locking support This patch adds POSIX file locking support to the fuse interface. This implementation doesn't keep any locking state in kernel. Unlocking on close() is handled by the FLUSH message, which now contains the lock owner id. Mandatory locking is not supported. The filesystem may enfoce mandatory locking in userspace if needed. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 05:48:52 -07:00
fuse: support BSD locking semantics It is trivial to add support for flock(2) semantics to the existing protocol, by setting the lock owner field to the file pointer, and passing a new FUSE_LK_FLOCK flag with the locking request. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 03:07:02 -07:00
fuse: implement ioctl support Generic ioctl support is tricky to implement because only the ioctl implementation itself knows which memory regions need to be read and/or written. To support this, fuse client can request retry of ioctl specifying memory regions to read and write. Deep copying (nested pointers) can be implemented by retrying multiple times resolving one depth of dereference at a time. For security and cleanliness considerations, ioctl implementation has restricted mode where the kernel determines data transfer directions and sizes using the _IOC_*() macros on the ioctl command. In this mode, retry is not allowed. For all FUSE servers, restricted mode is enforced. Unrestricted ioctl will be used by CUSE. Plese read the comment on top of fs/fuse/file.c::fuse_file_do_ioctl() for more information. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: implement poll support Implement poll support. Polled files are indexed using kh in a RB tree rooted at fuse_conn->polled_files. Client should send FUSE_NOTIFY_POLL notification once after processing FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set. Sending notification unconditionally after the latest poll or everytime file content might have changed is inefficient but won't cause malfunction. fuse_file_poll() can sleep and requires patches from the following thread which allows f_op->poll() to sleep. http://thread.gmane.org/gmane.linux.kernel/726176 Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
fuse: add FALLOCATE operation fallocate filesystem operation preallocates media space for the given file. If fallocate returns success then any subsequent write to the given range never fails with 'not enough space' error. Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-22 18:45:24 -07:00
fuse: allow private mappings of "direct_io" files Allow MAP_PRIVATE mmaps of "direct_io" files. This is necessary for execute support. MAP_SHARED mappings require some sort of coherency between the underlying file and the mapping. With "direct_io" it is difficult to provide this, so for the moment just disallow shared (read-write and read-only) mappings altogether. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:35 +02:00
[PATCH] FUSE - direct I/O This patch adds support for the "direct_io" mount option of FUSE. When this mount option is specified, the page cache is bypassed for read and write operations. This is useful for example, if the filesystem doesn't know the size of files before reading them, or when any kind of caching is harmful. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:35 -07:00
[PATCH] mark address_space_operations const Same as with already do with the file operations: keep them in .rodata and prevents people from doing runtime patching. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 04:26:44 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
fuse: Implement writepages callback The .writepages one is required to make each writeback request carry more than one page on it. The patch enables optimized behaviour unconditionally, i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0. [SzM: simplify, add comments] Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-29 21:45:29 +04:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] FUSE - readpages operation This patch adds readpages support to FUSE. With the help of the readpages() operation multiple reads are bundled together and sent as a single request to userspace. This can improve reading performace. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:33 -07:00
fuse: support writable mmap Quoting Linus (3 years ago, FUSE inclusion discussions): "User-space filesystems are hard to get right. I'd claim that they are almost impossible, unless you limit them somehow (shared writable mappings are the nastiest part - if you don't have those, you can reasonably limit your problems by limiting the number of dirty pages you accept through normal "write()" calls)." Instead of attempting the impossible, I've just waited for the dirty page accounting infrastructure to materialize (thanks to Peter Zijlstra and others). This nicely solved the biggest problem: limiting the number of pages used for write caching. Some small details remained, however, which this largish patch attempts to address. It provides a page writeback implementation for fuse, which is completely safe against VM related deadlocks. Performance may not be very good for certain usage patterns, but generally it should be acceptable. It has been tested extensively with fsx-linux and bash-shared-mapping. Fuse page writeback design -------------------------- fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM. It copies the contents of the original page, and queues a WRITE request to the userspace filesystem using this temp page. The writeback is finished instantly from the MM's point of view: the page is removed from the radix trees, and the PageDirty and PageWriteback flags are cleared. For the duration of the actual write, the NR_WRITEBACK_TEMP counter is incremented. The per-bdi writeback count is not decremented until the actual write completes. On dirtying the page, fuse waits for a previous write to finish before proceeding. This makes sure, there can only be one temporary page used at a time for one cached page. This approach is wasteful in both memory and CPU bandwidth, so why is this complication needed? The basic problem is that there can be no guarantee about the time in which the userspace filesystem will complete a write. It may be buggy or even malicious, and fail to complete WRITE requests. We don't want unrelated parts of the system to grind to a halt in such cases. Also a filesystem may need additional resources (particularly memory) to complete a WRITE request. There's a great danger of a deadlock if that allocation may wait for the writepage to finish. Currently there are several cases where the kernel can block on page writeback: - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER - page migration - throttle_vm_writeout (through NR_WRITEBACK) - sync(2) Of course in some cases (fsync, msync) we explicitly want to allow blocking. So for these cases new code has to be added to fuse, since the VM is not tracking writeback pages for us any more. As an extra safetly measure, the maximum dirty ratio allocated to a single fuse filesystem is set to 1% by default. This way one (or several) buggy or malicious fuse filesystems cannot slow down the rest of the system by hogging dirty memory. With appropriate privileges, this limit can be raised through '/sys/class/bdi/<bdi>/max_ratio'. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:54:41 -07:00
[PATCH] fuse: add bmap support Add support for the BMAP operation for block device based filesystems. This is needed to support swap-files and lilo. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 20:35:51 -08:00
fuse: O_DIRECT support for files Implement ->direct_IO() method in aops. The ->direct_IO() method combines the existing fuse_direct_read/fuse_direct_write methods to implement O_DIRECT functionality. Reaching ->direct_IO() in the read path via generic_file_aio_read ensures proper synchronization with page cache with its existing framework. Reaching ->direct_IO() in the write path via fuse_file_aio_write is made to come via generic_file_direct_write() which makes it play nice with the page cache w.r.t other mmap pages etc. On files marked 'direct_io' by the filesystem server, IO always follows the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT) and it always succeeds. On files not marked with 'direct_io' by the filesystem server, the IO path depends on O_DIRECT flag by the application. This can be passed at the time of open() as well as via fcntl(). Note that asynchronous O_DIRECT iocb jobs are completed synchronously always (this has been the case with FUSE even before this patch) Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-02-17 12:46:25 -05:00
fuse: Implement write_begin/write_end callbacks The .write_begin and .write_end are requiered to use generic routines (generic_file_aio_write --> ... --> generic_perform_write) for buffered writes. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-10 17:11:43 +04:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00
[PATCH] fuse: more flexible caching Make data caching behavior selectable on a per-open basis instead of per-mount. Compatibility for the old mount options 'kernel_cache' and 'direct_io' is retained in the userspace library (version 2.4.0-pre1 or later). Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:37 -07:00
[PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:10:30 -07:00