linux

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

Convert files to UTF-8 and some cleanups * Convert files to UTF-8. * Also correct some people's names (one example is Eißfeldt, which was found in a source file. Given that the author used an ß at all in a source file indicates that the real name has in fact a 'ß' and not an 'ss', which is commonly used as a substitute for 'ß' when limited to 7bit.) * Correct town names (Goettingen -> Göttingen) * Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313) Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Adrian Bunk <bunk@kernel.org>

2007-10-19 23:21:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

fs: remove prepare_write/commit_write Nothing uses prepare_write or commit_write. Remove them from the tree completely. [akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting] Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2008-10-29 14:00:55 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

Freezer: make kernel threads nonfreezable by default Currently, the freezer treats all tasks as freezable, except for the kernel threads that explicitly set the PF_NOFREEZE flag for themselves. This approach is problematic, since it requires every kernel thread to either set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't care for the freezing of tasks at all. It seems better to only require the kernel threads that want to or need to be frozen to use some freezer-related code and to remove any freezer-related code from the other (nonfreezable) kernel threads, which is done in this patch. The patch causes all kernel threads to be nonfreezable by default (ie. to have PF_NOFREEZE set by default) and introduces the set_freezable() function that should be called by the freezable kernel threads in order to unset PF_NOFREEZE. It also makes all of the currently freezable kernel threads call set_freezable(), so it shouldn't cause any (intentional) change of behaviour to appear. Additionally, it updates documentation to describe the freezing of tasks more accurately. [akpm@linux-foundation.org: build fixes] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: Pavel Machek <pavel@ucw.cz> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-07-17 04:03:35 -07:00

block: autoconvert trivial BKL users to private mutex The block device drivers have all gained new lock_kernel calls from a recent pushdown, and some of the drivers were already using the BKL before. This turns the BKL into a set of per-driver mutexes. Still need to check whether this is safe to do. file=$1 name=$2 if grep -q lock_kernel ${file} ; then if grep -q 'include.*linux.mutex.h' ${file} ; then sed -i '/include.*<linux\/smp_lock.h>/d' ${file} else sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file} fi sed -i ${file} \ -e "/^#include.*linux.mutex.h/,$ { 1,/^$static\|int\|long$/ { /^$static\|int\|long$/istatic DEFINE_MUTEX(${name}_mutex); } }" \ -e "s/$un$*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \ -e '/[ ]*cycle_kernel_lock();/d' else sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \ -e '/cycle_kernel_lock()/d' fi Signed-off-by: Arnd Bergmann <arnd@arndb.de>

2010-06-02 14:28:52 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] kthread: convert loop.c to kthread Convert loop.c from the deprecated kernel_thread to kthread. This patch simplifies the code quite a bit and passes similar testing to the previous submission on both emulated x86 and s390. Changes since last submission: switched to using a rather simple loop based on wait_event_interruptible. Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-09-29 01:59:11 -07:00

splice: divorce the splice structure/function definitions from the pipe header We need to move even more stuff into the header so that folks can use the splice_to_pipe() implementation instead of open-coding a lot of pipe knowledge (see relay implementation), so move to our own header file finally. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-04 09:59:47 +02:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

switch /dev/loop to vfs_iter_write() all writable files that might be used as backing store for /dev/loop already support ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-03 15:21:59 -04:00

move linux/loop.h to drivers/block Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-05-12 10:14:07 -04:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2008-03-26 12:11:53 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: remove the second argument of k[un]map_atomic() Signed-off-by: Cong Wang <amwang@redhat.com>

2011-11-25 23:14:18 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: remove the second argument of k[un]map_atomic() Signed-off-by: Cong Wang <amwang@redhat.com>

2011-11-25 23:14:18 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: ignore negative offset when calculate loop device size Negative offset may cause loop device size larger than backing file size. $ fallocate -l 1M a $ losetup --offset 0xffffffffffff0000 /dev/loop0 a $ blockdev --getsize64 /dev/loop0 1114112 $ ls -l a -rw-r--r-- 1 root root 1048576 Jan 23 12:46 a $ cat /dev/loop0 cat: /dev/loop0: Input/output error It makes no sense to do that. Only apply offset when it's positive. Fix a typo in the comment by the way. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:50 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: ignore negative offset when calculate loop device size Negative offset may cause loop device size larger than backing file size. $ fallocate -l 1M a $ losetup --offset 0xffffffffffff0000 /dev/loop0 a $ blockdev --getsize64 /dev/loop0 1114112 $ ls -l a -rw-r--r-- 1 root root 1048576 Jan 23 12:46 a $ cat /dev/loop0 cat: /dev/loop0: Input/output error It makes no sense to do that. Only apply offset when it's positive. Fix a typo in the comment by the way. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:50 -08:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: move common code into loop_figure_size() Update block device size in accord with gendisk size and let userspace know the change in loop_figure_size(). This is a clean up to remove common code of loop_figure_size()'s two callers. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:47 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loopdev: move common code into loop_figure_size() Update block device size in accord with gendisk size and let userspace know the change in loop_figure_size(). This is a clean up to remove common code of loop_figure_size()'s two callers. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:47 -08:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

switch /dev/loop to vfs_iter_write() all writable files that might be used as backing store for /dev/loop already support ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-03 15:21:59 -04:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

lift sb_start_write() out of ->write() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-03-20 13:04:20 -04:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

lift sb_start_write() out of ->write() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-03-20 13:04:20 -04:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

block: loop: say goodby to bio Switch to block request completely. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:22:58 +00:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

block: Convert bio_for_each_segment() to bvec_iter More prep work for immutable biovecs - with immutable bvecs drivers won't be able to use the biovec directly, they'll need to use helpers that take into account bio->bi_iter.bi_bvec_done. This updates callers for the new usage without changing the implementation yet. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Paul Clements <Paul.Clements@steeleye.com> Cc: Jim Paris <jim@jtan.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com> Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com> Cc: support@lsi.com Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jan Kara <jack@suse.cz> Cc: linux-m68k@lists.linux-m68k.org Cc: linuxppc-dev@lists.ozlabs.org Cc: drbd-user@lists.linbit.com Cc: nbd-general@lists.sourceforge.net Cc: cbe-oss-dev@lists.ozlabs.org Cc: xen-devel@lists.xensource.com Cc: virtualization@lists.linux-foundation.org Cc: linux-raid@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: DL-MPTFusionLinux@lsi.com Cc: linux-scsi@vger.kernel.org Cc: devel@driverdev.osuosl.org Cc: linux-fsdevel@vger.kernel.org Cc: cluster-devel@redhat.com Cc: linux-mm@kvack.org Acked-by: Geoff Levand <geoff@infradead.org>

2013-11-23 17:19:00 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

block: loop: say goodby to bio Switch to block request completely. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:22:58 +00:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: convert to using splice_direct_to_actor() instead of sendfile() This gets rid of the dependency on ->sendfile() for receiving data and converts loop to ->splice_read() instead. Also includes an IV offset fix from Hugh Dickins. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-12 21:20:37 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: convert to using splice_direct_to_actor() instead of sendfile() This gets rid of the dependency on ->sendfile() for receiving data and converts loop to ->splice_read() instead. Also includes an IV offset fix from Hugh Dickins. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-12 21:20:37 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: convert to using splice_direct_to_actor() instead of sendfile() This gets rid of the dependency on ->sendfile() for receiving data and converts loop to ->splice_read() instead. Also includes an IV offset fix from Hugh Dickins. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-12 21:20:37 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: convert to using splice_direct_to_actor() instead of sendfile() This gets rid of the dependency on ->sendfile() for receiving data and converts loop to ->splice_read() instead. Also includes an IV offset fix from Hugh Dickins. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-12 21:20:37 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: convert to using splice_direct_to_actor() instead of sendfile() This gets rid of the dependency on ->sendfile() for receiving data and converts loop to ->splice_read() instead. Also includes an IV offset fix from Hugh Dickins. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2007-06-12 21:20:37 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: zero fill bio instead of return -EIO for partial read commit 8268f5a741 ("deny partial write for loop dev fd") tried to fix the loop device partial read information leak problem. But it changed the semantics of read behavior. When we read beyond the end of the device we should get 0 bytes, which is normal behavior, we should not just return -EIO Instead of returning -EIO, zero out the bio to avoid information leak in case of partail read. Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Tested-by: Jeff Moyer <jmoyer@redhat.com> Cc: Dmitry Monakhov <dmonakhov@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2012-02-08 22:07:19 +01:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

block: loop: say goodby to bio Switch to block request completely. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:22:58 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: zero fill bio instead of return -EIO for partial read commit 8268f5a741 ("deny partial write for loop dev fd") tried to fix the loop device partial read information leak problem. But it changed the semantics of read behavior. When we read beyond the end of the device we should get 0 bytes, which is normal behavior, we should not just return -EIO Instead of returning -EIO, zero out the bio to avoid information leak in case of partail read. Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Tested-by: Jeff Moyer <jmoyer@redhat.com> Cc: Dmitry Monakhov <dmonakhov@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2012-02-08 22:07:19 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: introduce lo_discard() and lo_req_flush() No behaviour change, just move the handling for REQ_DISCARD and REQ_FLUSH in these two functions. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:22:59 +00:00

2015-08-17 10:31:51 +08:00

block, drivers, cgroup: use op_is_write helper instead of checking for REQ_WRITE We currently set REQ_WRITE/WRITE for all non READ IOs like discard, flush, writesame, etc. In the next patches where we no longer set up the op as a bitmap, we will not be able to detect a operation direction like writesame by testing if REQ_WRITE is set. This patch converts the drivers and cgroup to use the op_is_write helper. This should just cover the simple cases. I did dm, md and bcache in their own patches because they were more involved. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-06-05 14:31:45 -05:00

2015-08-17 10:31:51 +08:00

Merge branch 'for-4.4/core' into for-4.4/drivers Signed-off-by: Jens Axboe <axboe@fb.com>

2015-10-09 10:40:29 -06:00

2015-08-17 10:31:51 +08:00

block: loop: fix filesystem corruption in case of aio/dio Starting from commit e36f620428(block: split bios to max possible length), block core starts to split bio in the middle of bvec. Unfortunately loop dio/aio doesn't consider this situation, and always treat 'iter.iov_offset' as zero. Then filesystem corruption is observed. This patch figures out the offset of the base bvevc via 'bio->bi_iter.bi_bvec_done' and fixes the issue by passing the offset to iov iterator. Fixes: e36f6204288088f (block: split bios to max possible length) Cc: Keith Busch <keith.busch@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org (4.5) Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-04-15 18:51:28 +08:00

2015-08-17 10:31:51 +08:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

2015-08-17 10:31:51 +08:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

2015-08-17 10:31:51 +08:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

block: loop: don't handle REQ_FUA explicitly block core handles REQ_FUA by its flush state machine, so won't do it in loop explicitly. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:23:00 +00:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

loop: make do_req_filebacked more robust Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:01 +02:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

2005-06-23 00:09:06 -07:00

2014-12-31 13:22:57 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: Flush possible running bios when loop device is released. When there are still queued bios and reference count drops to zero, loop device must flush all queued bios. Otherwise it can lead to situation that caller closes the device, but some bios are still running and endio() function call later OOpses when uses unallocated mempool. This happens for example when running dm-crypt over loop, here is typical oops backtrace: Oops: 0000 [#1] PREEMPT SMP EIP is at mempool_free+0x12/0x6b ... crypt_dec_pending+0x50/0x54 [dm_crypt] crypt_endio+0x9f/0xa7 [dm_crypt] crypt_endio+0x0/0xa7 [dm_crypt] bio_endio+0x2b/0x2e loop_thread+0x37a/0x3b1 do_lo_send_aops+0x0/0x165 autoremove_wake_function+0x0/0x33 loop_thread+0x0/0x3b1 kthread+0x3b/0x61 kthread+0x0/0x61 kernel_thread_helper+0x7/0x10 (But crash is reproducible with different dm targets running over loop device too.) Patch fixes it by flushing the bios in release call, reusing the flush mechanism for switching backing store. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2008-12-12 14:48:27 +01:00

block: loop: fix another reread part failure loop_clr_fd() can be run piggyback with lo_release(), and under this situation, reread partition may always fail because bd_mutex has been held already. This patch detects the situation by the reference count, and call __blkdev_reread_part() to avoid acquiring the lock again. In the meantime, this patch switches to new kernel APIs of blkdev_reread_part() and __blkdev_reread_part(). Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:24 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: fix another reread part failure loop_clr_fd() can be run piggyback with lo_release(), and under this situation, reread partition may always fail because bd_mutex has been held already. This patch detects the situation by the reference count, and call __blkdev_reread_part() to avoid acquiring the lock again. In the meantime, this patch switches to new kernel APIs of blkdev_reread_part() and __blkdev_reread_part(). Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:24 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: fix deadlock when sysfs and LOOP_CLR_FD race against each other LOOP_CLR_FD takes lo->lo_ctl_mutex and tries to remove the loop sysfs files. Sysfs calls show() and waits for lo->lo_ctl_mutex. LOOP_CLR_FD waits for show() to finish to remove the sysfs file. cat /sys/class/block/loop0/loop/backing_file mutex_lock_nested+0x176/0x350 ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] loop_attr_do_show_backing_file+0x2f/0xd0 [loop] dev_attr_show+0x1b/0x60 ? sysfs_read_file+0x86/0x1a0 ? __get_free_pages+0x12/0x50 sysfs_read_file+0xaf/0x1a0 ioctl(LOOP_CLR_FD): wait_for_common+0x12c/0x180 ? try_to_wake_up+0x2a0/0x2a0 wait_for_completion+0x18/0x20 sysfs_deactivate+0x178/0x180 ? sysfs_addrm_finish+0x43/0x70 ? sysfs_addrm_start+0x1d/0x20 sysfs_addrm_finish+0x43/0x70 sysfs_hash_and_remove+0x85/0xa0 sysfs_remove_group+0x59/0x100 loop_clr_fd+0x1dc/0x3f0 [loop] lo_ioctl+0x223/0x7a0 [loop] Instead of taking the lo_ctl_mutex from sysfs code, take the inner lo->lo_lock, to protect the access to the backing_file data. Thanks to Tejun for help debugging and finding a solution. Cc: Milan Broz <mbroz@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: stable@kernel.org Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:21:35 +02:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

vfs: add file_path() helper Turn d_path(&file->f_path, ...); into file_path(file, ...); Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-06-19 10:29:13 +02:00

loop: fix deadlock when sysfs and LOOP_CLR_FD race against each other LOOP_CLR_FD takes lo->lo_ctl_mutex and tries to remove the loop sysfs files. Sysfs calls show() and waits for lo->lo_ctl_mutex. LOOP_CLR_FD waits for show() to finish to remove the sysfs file. cat /sys/class/block/loop0/loop/backing_file mutex_lock_nested+0x176/0x350 ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] loop_attr_do_show_backing_file+0x2f/0xd0 [loop] dev_attr_show+0x1b/0x60 ? sysfs_read_file+0x86/0x1a0 ? __get_free_pages+0x12/0x50 sysfs_read_file+0xaf/0x1a0 ioctl(LOOP_CLR_FD): wait_for_common+0x12c/0x180 ? try_to_wake_up+0x2a0/0x2a0 wait_for_completion+0x18/0x20 sysfs_deactivate+0x178/0x180 ? sysfs_addrm_finish+0x43/0x70 ? sysfs_addrm_start+0x1d/0x20 sysfs_addrm_finish+0x43/0x70 sysfs_hash_and_remove+0x85/0xa0 sysfs_remove_group+0x59/0x100 loop_clr_fd+0x1dc/0x3f0 [loop] lo_ioctl+0x223/0x7a0 [loop] Instead of taking the lo_ctl_mutex from sysfs code, take the inner lo->lo_lock, to protect the access to the backing_file data. Thanks to Tejun for help debugging and finding a solution. Cc: Milan Broz <mbroz@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: stable@kernel.org Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:21:35 +02:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

drivers/block/loop.c: fix comment typo in loop_config_discard Discard requests are ignored if the encryption is enabled for the given loop device. Update comment to match the code, and similar comments elsewhere in the file. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2014-01-21 14:39:24 -08:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

block: have drivers use blk_queue_max_discard_sectors() Some drivers use it now, others just set the limits field manually. But in preparation for splitting this into a hard and soft limit, ensure that they all call the proper function for setting the hw limit for discards. Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-07-14 08:15:12 -06:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

loop: Fix discard_alignment default setting discard_alignment is not relevant to the loop driver since it is supposed to be set as a workaround for the old sector 63 alignments. So set it to zero rather than block size. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reported-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-12-02 14:47:03 +01:00

block: have drivers use blk_queue_max_discard_sectors() Some drivers use it now, others just set the limits field manually. But in preparation for splitting this into a hard and soft limit, ensure that they all call the proper function for setting the hw limit for discards. Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-07-14 08:15:12 -06:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

switch /dev/loop to vfs_iter_write() all writable files that might be used as backing store for /dev/loop already support ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-03 15:21:59 -04:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

[PATCH] inode-diet: Eliminate i_blksize from the inode structure This eliminates the i_blksize field from struct inode. Filesystems that want to provide a per-inode st_blksize can do so by providing their own getattr routine instead of using the generic_fillattr() function. Note that some filesystems were providing pretty much random (and incorrect) values for i_blksize. [bunk@stusta.de: cleanup] [akpm@osdl.org: generic_fillattr() fix] Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-09-27 01:50:49 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

block: loop: convert to per-device workqueue Documentation/workqueue.txt: If there is dependency among multiple work items used during memory reclaim, they should be queued to separate wq each with WQ_MEM_RECLAIM. Loop devices can be stacked, so we have to convert to per-device workqueue. One example is Fedora live CD. Fixes: b5dd2f6047ca108001328aac0e8588edd15f1778 Cc: stable@vger.kernel.org (v4.0) Cc: Justin M. Forbes <jforbes@fedoraproject.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-05 19:49:54 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: remove the incorrect write_begin/write_end shortcut Currently the loop device tries to call directly into write_begin/write_end instead of going through ->write if it can. This is a fairly nasty shortcut as write_begin and write_end are only callbacks for the generic write code and expect to be called with filesystem specific locks held. This code currently causes various issues for clustered filesystems as it doesn't take the required cluster locks, and it also causes issues for XFS as it doesn't properly lock against the swapext ioctl as called by the defragmentation tools. This in case causes data corruption if defragmentation hits a busy loop device in the wrong time window, as reported by RH QA. The reason why we have this shortcut is that it saves a data copy when doing a transformation on the loop device, which is the technical term for using cryptoloop (or an XOR transformation). Given that cryptoloop has been deprecated in favour of dm-crypt my opinion is that we should simply drop this shortcut instead of finding complicated ways to to introduce a formal interface for this shortcut. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-10-17 12:57:20 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: support barrier writes Honour barrier requests in the loop back block device driver. In case of barrier bios, flush the backing file once before processing the barrier and once after to guarantee ordering. In case of filesystems that does not support fsync, barrier bios would be failed with -EOPNOTSUPP. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:29:54 +01:00

loop: switch to using blk_queue_write_cache() Signed-off-by: Jens Axboe <axboe@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de>

2016-03-30 10:09:35 -06:00

loop: support barrier writes Honour barrier requests in the loop back block device driver. In case of barrier bios, flush the backing file once before processing the barrier and once after to guarantee ordering. In case of filesystems that does not support fsync, barrier bios would be failed with -EOPNOTSUPP. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:29:54 +01:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: add some basic read-only sysfs attributes Create /sys/block/loopX/loop directory and provide these attributes: - backing_file - autoclear - offset - sizelimit This loop directory is present only if loop device is configured. To be used in util-linux-ng (and possibly elsewhere like udev rules) where code need to get loop attributes from kernel (and not store duplicate info in userspace). Moreover loop ioctls are not even able to provide full backing file info because of buffer limits. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-08-23 15:16:00 +02:00

generate "change" uevent for loop device Recent udev versions probe loop devices for filesystems meaning that the /dev/disk hierarchy may contain useful entries such as $ ls -l /dev/disk/by-label/Fedora-12-x86_64-Live lrwxrwxrwx 1 root root 11 Mar 11 13:41 /dev/disk/by-label/Fedora-12-x86_64-Live -> ../../loop0 Unfortunately, no "change" uevent is generated when the loop device is detached so the symlink persists. Additionally, no "change" uevent is guaranteed to be generated when attaching an fd or changing capacity. For example, user space could open the loop device O_RDONLY (in fact, recent util-linux-ng does this) so udev's OPTIONS+="watch" machinery may not trigger the "change" uevent. This patch ensures that the "change" uevent is generated in all of these cases. As a result, the /dev/disk hierarchy works as expected for loop devices. Signed-off-by: David Zeuthen <davidz@redhat.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2010-05-03 14:08:59 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] kthread: convert loop.c to kthread Convert loop.c from the deprecated kernel_thread to kthread. This patch simplifies the code quite a bit and passes similar testing to the previous submission on both emulated x86 and s390. Changes since last submission: switched to using a rather simple loop based on wait_event_interruptible. Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-09-29 01:59:11 -07:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: fix another reread part failure loop_clr_fd() can be run piggyback with lo_release(), and under this situation, reread partition may always fail because bd_mutex has been held already. This patch detects the situation by the reference count, and call __blkdev_reread_part() to avoid acquiring the lock again. In the meantime, this patch switches to new kernel APIs of blkdev_reread_part() and __blkdev_reread_part(). Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:24 +08:00

loop: prevent bdev freeing while device in use struct block_device lifecycle is defined by its inode (see fs/block_dev.c) - block_device allocated first time we access /dev/loopXX and deallocated on bdev_destroy_inode. When we create the device "losetup /dev/loopXX afile" we want that block_device stay alive until we destroy the loop device with "losetup -d". But because we do not hold /dev/loopXX inode its counter goes 0, and inode/bdev can be destroyed at any moment. Usually it happens at memory pressure or when user drops inode cache (like in the test below). When later in loop_clr_fd() we want to use bdev we have use-after-free error with following stack: BUG: unable to handle kernel NULL pointer dereference at 0000000000000280 bd_set_size+0x10/0xa0 loop_clr_fd+0x1f8/0x420 [loop] lo_ioctl+0x200/0x7e0 [loop] lo_compat_ioctl+0x47/0xe0 [loop] compat_blkdev_ioctl+0x341/0x1290 do_filp_open+0x42/0xa0 compat_sys_ioctl+0xc1/0xf20 do_sys_open+0x16e/0x1d0 sysenter_dispatch+0x7/0x1a To prevent use-after-free we need to grab the device in loop_set_fd() and put it later in loop_clr_fd(). The issue is reprodusible on current Linus head and v3.3. Here is the test: dd if=/dev/zero of=loop.file bs=1M count=1 while [ true ]; do losetup /dev/loop0 loop.file echo 2 > /proc/sys/vm/drop_caches losetup -d /dev/loop0 done [ Doing bdgrab/bput in loop_set_fd/loop_clr_fd is safe, because every time we call loop_set_fd() we check that loop_device->lo_state is Lo_unbound and set it to Lo_bound If somebody will try to set_fd again it will get EBUSY. And if we try to loop_clr_fd() on unbound loop device we'll get ENXIO. loop_set_fd/loop_clr_fd (and any other loop ioctl) is called under loop_device->lo_ctl_mutex. ] Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-04-01 09:47:56 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() If the loop device is associated (lo->lo_state == Lo_bound), it will have a valid bdev pointed to by lo->lo_device. There is no reason to ever pass an additional block_device pointer. Signed-off-by: Ayan George <ayan.george@canonical.com> Cc: Phillip Susi <psusi@cfl.rr.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-09-21 10:02:13 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] gfp_t: remaining bits of drivers/* Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2005-10-21 03:22:34 -04:00

drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() If the loop device is associated (lo->lo_state == Lo_bound), it will have a valid bdev pointed to by lo->lo_device. There is no reason to ever pass an additional block_device pointer. Signed-off-by: Ayan George <ayan.george@canonical.com> Cc: Phillip Susi <psusi@cfl.rr.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-09-21 10:02:13 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: Make explicit loop device destruction lazy xfstests has always had random failures of tests due to loop devices failing to be torn down and hence leaving filesytems that cannot be unmounted. This causes test runs to immediately stop. Over the past 6 or 7 years we've added hacks like explicit unmount -d commands for loop mounts, losetup -d after unmount -d fails, etc, but still the problems persist. Recently, the frequency of loop related failures increased again to the point that xfstests 259 will reliably fail with a stray loop device that was not torn down. That is despite the fact the test is above as simple as it gets - loop 5 or 6 times running mkfs.xfs with different paramters: lofile=$(losetup -f) losetup $lofile "$testfile" "$MKFS_XFS_PROG" -b size=512 $lofile >/dev/null || echo "mkfs failed!" sync losetup -d $lofile And losteup -d $lofile is failing with EBUSY on 1-3 of these loops every time the test is run. Turns out that blkid is running simultaneously with losetup -d, and so it sees an elevated reference count and returns EBUSY. But why is blkid running? It's obvious, isn't it? udev has decided to try and find out what is on the block device as a result of a creation notification. And it is racing with mkfs, so might still be scanning the device when mkfs finishes and we try to tear it down. So, make losetup -d force autoremove behaviour. That is, when the last reference goes away, tear down the device. xfstests wants it *gone*, not causing random teardown failures when we know that all the operations the tests have specifically run on the device have completed and are no longer referencing the loop device. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2012-09-28 10:42:23 +02:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

loop: Make explicit loop device destruction lazy xfstests has always had random failures of tests due to loop devices failing to be torn down and hence leaving filesytems that cannot be unmounted. This causes test runs to immediately stop. Over the past 6 or 7 years we've added hacks like explicit unmount -d commands for loop mounts, losetup -d after unmount -d fails, etc, but still the problems persist. Recently, the frequency of loop related failures increased again to the point that xfstests 259 will reliably fail with a stray loop device that was not torn down. That is despite the fact the test is above as simple as it gets - loop 5 or 6 times running mkfs.xfs with different paramters: lofile=$(losetup -f) losetup $lofile "$testfile" "$MKFS_XFS_PROG" -b size=512 $lofile >/dev/null || echo "mkfs failed!" sync losetup -d $lofile And losteup -d $lofile is failing with EBUSY on 1-3 of these loops every time the test is run. Turns out that blkid is running simultaneously with losetup -d, and so it sees an elevated reference count and returns EBUSY. But why is blkid running? It's obvious, isn't it? udev has decided to try and find out what is on the block device as a result of a creation notification. And it is racing with mkfs, so might still be scanning the device when mkfs finishes and we try to tear it down. So, make losetup -d force autoremove behaviour. That is, when the last reference goes away, tear down the device. xfstests wants it *gone*, not causing random teardown failures when we know that all the operations the tests have specifically run on the device have completed and are no longer referencing the loop device. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2012-09-28 10:42:23 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: fix deadlock when sysfs and LOOP_CLR_FD race against each other LOOP_CLR_FD takes lo->lo_ctl_mutex and tries to remove the loop sysfs files. Sysfs calls show() and waits for lo->lo_ctl_mutex. LOOP_CLR_FD waits for show() to finish to remove the sysfs file. cat /sys/class/block/loop0/loop/backing_file mutex_lock_nested+0x176/0x350 ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] ? loop_attr_do_show_backing_file+0x2f/0xd0 [loop] loop_attr_do_show_backing_file+0x2f/0xd0 [loop] dev_attr_show+0x1b/0x60 ? sysfs_read_file+0x86/0x1a0 ? __get_free_pages+0x12/0x50 sysfs_read_file+0xaf/0x1a0 ioctl(LOOP_CLR_FD): wait_for_common+0x12c/0x180 ? try_to_wake_up+0x2a0/0x2a0 wait_for_completion+0x18/0x20 sysfs_deactivate+0x178/0x180 ? sysfs_addrm_finish+0x43/0x70 ? sysfs_addrm_start+0x1d/0x20 sysfs_addrm_finish+0x43/0x70 sysfs_hash_and_remove+0x85/0xa0 sysfs_remove_group+0x59/0x100 loop_clr_fd+0x1dc/0x3f0 [loop] lo_ioctl+0x223/0x7a0 [loop] Instead of taking the lo_ctl_mutex from sysfs code, take the inner lo->lo_lock, to protect the access to the backing_file data. Thanks to Tejun for help debugging and finding a solution. Cc: Milan Broz <mbroz@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: stable@kernel.org Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:21:35 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: prevent bdev freeing while device in use struct block_device lifecycle is defined by its inode (see fs/block_dev.c) - block_device allocated first time we access /dev/loopXX and deallocated on bdev_destroy_inode. When we create the device "losetup /dev/loopXX afile" we want that block_device stay alive until we destroy the loop device with "losetup -d". But because we do not hold /dev/loopXX inode its counter goes 0, and inode/bdev can be destroyed at any moment. Usually it happens at memory pressure or when user drops inode cache (like in the test below). When later in loop_clr_fd() we want to use bdev we have use-after-free error with following stack: BUG: unable to handle kernel NULL pointer dereference at 0000000000000280 bd_set_size+0x10/0xa0 loop_clr_fd+0x1f8/0x420 [loop] lo_ioctl+0x200/0x7e0 [loop] lo_compat_ioctl+0x47/0xe0 [loop] compat_blkdev_ioctl+0x341/0x1290 do_filp_open+0x42/0xa0 compat_sys_ioctl+0xc1/0xf20 do_sys_open+0x16e/0x1d0 sysenter_dispatch+0x7/0x1a To prevent use-after-free we need to grab the device in loop_set_fd() and put it later in loop_clr_fd(). The issue is reprodusible on current Linus head and v3.3. Here is the test: dd if=/dev/zero of=loop.file bs=1M count=1 while [ true ]; do losetup /dev/loop0 loop.file echo 2 > /proc/sys/vm/drop_caches losetup -d /dev/loop0 done [ Doing bdgrab/bput in loop_set_fd/loop_clr_fd is safe, because every time we call loop_set_fd() we check that loop_device->lo_state is Lo_unbound and set it to Lo_bound If somebody will try to set_fd again it will get EBUSY. And if we try to loop_clr_fd() on unbound loop device we'll get ENXIO. loop_set_fd/loop_clr_fd (and any other loop ioctl) is called under loop_device->lo_ctl_mutex. ] Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-04-01 09:47:56 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

loop: prevent bdev freeing while device in use struct block_device lifecycle is defined by its inode (see fs/block_dev.c) - block_device allocated first time we access /dev/loopXX and deallocated on bdev_destroy_inode. When we create the device "losetup /dev/loopXX afile" we want that block_device stay alive until we destroy the loop device with "losetup -d". But because we do not hold /dev/loopXX inode its counter goes 0, and inode/bdev can be destroyed at any moment. Usually it happens at memory pressure or when user drops inode cache (like in the test below). When later in loop_clr_fd() we want to use bdev we have use-after-free error with following stack: BUG: unable to handle kernel NULL pointer dereference at 0000000000000280 bd_set_size+0x10/0xa0 loop_clr_fd+0x1f8/0x420 [loop] lo_ioctl+0x200/0x7e0 [loop] lo_compat_ioctl+0x47/0xe0 [loop] compat_blkdev_ioctl+0x341/0x1290 do_filp_open+0x42/0xa0 compat_sys_ioctl+0xc1/0xf20 do_sys_open+0x16e/0x1d0 sysenter_dispatch+0x7/0x1a To prevent use-after-free we need to grab the device in loop_set_fd() and put it later in loop_clr_fd(). The issue is reprodusible on current Linus head and v3.3. Here is the test: dd if=/dev/zero of=loop.file bs=1M count=1 while [ true ]; do losetup /dev/loop0 loop.file echo 2 > /proc/sys/vm/drop_caches losetup -d /dev/loop0 done [ Doing bdgrab/bput in loop_set_fd/loop_clr_fd is safe, because every time we call loop_set_fd() we check that loop_device->lo_state is Lo_unbound and set it to Lo_bound If somebody will try to set_fd again it will get EBUSY. And if we try to loop_clr_fd() on unbound loop device we'll get ENXIO. loop_set_fd/loop_clr_fd (and any other loop ioctl) is called under loop_device->lo_ctl_mutex. ] Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-04-01 09:47:56 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: Properly clear sysfs in autoclear mode In autoclear mode bdev is NULL but the sysfs entry should be destroyed otherwise this warning appears: WARNING: at fs/sysfs/dir.c:451 sysfs_add_one+0x82/0x95() sysfs: cannot create duplicate filename '/devices/virtual/block/loop0/loop' Fixes commit ee86273062cbb310665fe49e1f1937d2cf85b0b9 Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2010-10-27 19:51:30 -06:00

generate "change" uevent for loop device Recent udev versions probe loop devices for filesystems meaning that the /dev/disk hierarchy may contain useful entries such as $ ls -l /dev/disk/by-label/Fedora-12-x86_64-Live lrwxrwxrwx 1 root root 11 Mar 11 13:41 /dev/disk/by-label/Fedora-12-x86_64-Live -> ../../loop0 Unfortunately, no "change" uevent is generated when the loop device is detached so the symlink persists. Additionally, no "change" uevent is guaranteed to be generated when attaching an fd or changing capacity. For example, user space could open the loop device O_RDONLY (in fact, recent util-linux-ng does this) so udev's OPTIONS+="watch" machinery may not trigger the "change" uevent. This patch ensures that the "change" uevent is generated in all of these cases. As a result, the /dev/disk hierarchy works as expected for loop devices. Signed-off-by: David Zeuthen <davidz@redhat.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2010-05-03 14:08:59 +02:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

generate "change" uevent for loop device Recent udev versions probe loop devices for filesystems meaning that the /dev/disk hierarchy may contain useful entries such as $ ls -l /dev/disk/by-label/Fedora-12-x86_64-Live lrwxrwxrwx 1 root root 11 Mar 11 13:41 /dev/disk/by-label/Fedora-12-x86_64-Live -> ../../loop0 Unfortunately, no "change" uevent is generated when the loop device is detached so the symlink persists. Additionally, no "change" uevent is guaranteed to be generated when attaching an fd or changing capacity. For example, user space could open the loop device O_RDONLY (in fact, recent util-linux-ng does this) so udev's OPTIONS+="watch" machinery may not trigger the "change" uevent. This patch ensures that the "change" uevent is generated in all of these cases. As a result, the /dev/disk hierarchy works as expected for loop devices. Signed-off-by: David Zeuthen <davidz@redhat.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2010-05-03 14:08:59 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

Revert "loop: cleanup partitions when detaching loop device" This reverts commit 8761a3dc1f07b163414e2215a2cadbb4cfe2a107. There are situations where the destruction path is called with the bdev->bd_mutex already held, which then deadlocks in loop_clr_fd(). The normal partition cleanup does a trylock() on the mutex, but it'd be nice to have a more bullet proof method in loop. So punt this more involved fix to the next merge window, and just back out this buggy fix for now. Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-04-08 10:12:11 +02:00

block: loop: fix another reread part failure loop_clr_fd() can be run piggyback with lo_release(), and under this situation, reread partition may always fail because bd_mutex has been held already. This patch detects the situation by the reference count, and call __blkdev_reread_part() to avoid acquiring the lock again. In the meantime, this patch switches to new kernel APIs of blkdev_reread_part() and __blkdev_reread_part(). Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:24 +08:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

loop: fix circular locking in loop_clr_fd() With CONFIG_PROVE_LOCKING enabled $ losetup /dev/loop0 file $ losetup -o 32256 /dev/loop1 /dev/loop0 $ losetup -d /dev/loop1 $ losetup -d /dev/loop0 triggers a [ INFO: possible circular locking dependency detected ] I think this warning is a false positive. Open/close on a loop device acquires bd_mutex of the device before acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of a device, if backing file is a device and this is the last reference to the file being dropped . But it is guaranteed that it is impossible to have a circular list of backing devices.(say loop2->loop1->loop0->loop2 is not possible), which guarantees that this can never deadlock. So this warning should be suppressed. It is very difficult to annotate lockdep not to warn here in the correct way. A simple way to silence lockdep could be to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some other real bugs. @@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, struct loop_device *lo = bdev->bd_disk->private_data; int err; - mutex_lock(&lo->lo_ctl_mutex); + mutex_lock_nested(&lo->lo_ctl_mutex, 1); switch (cmd) { case LOOP_SET_FD: err = loop_set_fd(lo, mode, bdev, arg); Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be a better solution. Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex held, so no lockdep annotation is required. If you do not like the special handling of the lo_ctl_mutex just for the LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside each of the individual ioctl handlers and I could send you another patch. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:33:41 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

userns: Convert loop to use kuid_t instead of uid_t Cc: Jens Axboe <jaxboe@fusionio.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

2012-02-11 11:23:51 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

CRED: Wrap task credential accesses in the block loopback driver Wrap access to task credentials so that they can be separated more easily from the task_struct during the introduction of COW creds. Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id(). Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more sense to use RCU directly rather than a convenient wrapper; these will be addressed by later patches. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: James Morris <jmorris@namei.org>

2008-11-14 10:38:41 +11:00

userns: Convert loop to use kuid_t instead of uid_t Cc: Jens Axboe <jaxboe@fusionio.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

2012-02-11 11:23:51 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: move common code into loop_figure_size() Update block device size in accord with gendisk size and let userspace know the change in loop_figure_size(). This is a clean up to remove common code of loop_figure_size()'s two callers. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:47 -08:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: update block device size in loop_set_status() Loop device driver sometimes fails to impose the size limit on the device. Keep issuing following two commands: losetup --offset 7517244416 --sizelimit 3224971264 /dev/loop0 backed_file blockdev --getsize64 /dev/loop0 blockdev reports file size instead of sizelimit several out of 100 times. The problems are: - losetup set up the device in two ioctl: LOOP_SET_FD and LOOP_SET_STATUS64. - LOOP_SET_STATUS64 only update size of gendisk. Block device size will be updated lazily when device comes to use. If udev rushes in between the two ioctl, it will bring in a block device whose size is backing file size. If the device is not released after LOOP_SET_STATUS64 ioctl, blockdev will not see the updated size. Update block size in LOOP_SET_STATUS64 ioctl. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Reported-by: M. Hindess <hindessm@uk.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:46 -08:00

loop: add discard support for loop devices This commit adds discard support for loop devices. Discard is usually supported by SSD and thinly provisioned devices as a method for reclaiming unused space. This is no different than trying to reclaim back space which is not used by the file system on the image, but it still occupies space on the host file system. We can do the reclamation on file system which does support hole punching. So when discard request gets to the loop driver we can translate that to punch a hole to the underlying file, hence reclaim the free space. This is very useful for trimming down the size of the image to only what is really used by the file system on that image. Fstrim may be used for that purpose. It has been tested on ext4, xfs and btrfs with the image file systems ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has some problems but it seems that ext4 punch hole implementation is somewhat flawed and it is unrelated to this commit. Also this is a very good method of validating file systems punch hole implementation. Note that when encryption is used, discard support is disabled, because using it might leak some information useful for possible attacker. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-19 14:50:46 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

Allow auto-destruction of loop devices This allows a flag to be set on loop devices so that when they are closed for the last time, they'll self-destruct. In general, so that we can automatically allocate loop devices (as with losetup -f) and have them disappear when we're done with them. In particular, right now, so that we can stop relying on the hackish special-case in umount(8) which kills off loop devices which were set up by 'mount -oloop'. That means we can stop putting crap in /etc/mtab which doesn't belong there, which means it can be a symlink to /proc/mounts, which means yet another writable file on the root filesystem is eliminated and the 'stateless' folks get happier... and OLPC trac #356 can be closed. The mount(8) side of that is at http://marc.info/?l=util-linux-ng&m=119362955431694&w=2 [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: David Woodhouse <dwmw2@infradead.org> Cc: Bernardo Innocenti <bernie@codewiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2008-02-06 01:36:27 -08:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

block: loop: fix another reread part failure loop_clr_fd() can be run piggyback with lo_release(), and under this situation, reread partition may always fail because bd_mutex has been held already. This patch detects the situation by the reference count, and call __blkdev_reread_part() to avoid acquiring the lock again. In the meantime, this patch switches to new kernel APIs of blkdev_reread_part() and __blkdev_reread_part(). Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:24 +08:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

CRED: Wrap task credential accesses in the block loopback driver Wrap access to task credentials so that they can be separated more easily from the task_struct during the introduction of COW creds. Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id(). Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more sense to use RCU directly rather than a convenient wrapper; these will be addressed by later patches. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: James Morris <jmorris@namei.org>

2008-11-14 10:38:41 +11:00

block: loop: switch to VFS ITER_BVEC Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2015-04-07 18:23:29 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: prepare for supporing direct IO This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:49 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

switch vfs_getattr() to struct path Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-01-24 02:18:08 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2009-03-31 15:23:43 -07:00

loopdev: move common code into loop_figure_size() Update block device size in accord with gendisk size and let userspace know the change in loop_figure_size(). This is a clean up to remove common code of loop_figure_size()'s two callers. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:47 -08:00

2009-03-31 15:23:43 -07:00

loopdev: move common code into loop_figure_size() Update block device size in accord with gendisk size and let userspace know the change in loop_figure_size(). This is a clean up to remove common code of loop_figure_size()'s two callers. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:47 -08:00

2009-03-31 15:23:43 -07:00

block: loop: introduce ioctl command of LOOP_SET_DIRECT_IO If loop block is mounted via 'mount -o loop', it isn't easy to pass file descriptor opened as O_DIRECT, so this patch introduces a new command to support direct IO for this case. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:50 +08:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: fix circular locking in loop_clr_fd() With CONFIG_PROVE_LOCKING enabled $ losetup /dev/loop0 file $ losetup -o 32256 /dev/loop1 /dev/loop0 $ losetup -d /dev/loop1 $ losetup -d /dev/loop0 triggers a [ INFO: possible circular locking dependency detected ] I think this warning is a false positive. Open/close on a loop device acquires bd_mutex of the device before acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of a device, if backing file is a device and this is the last reference to the file being dropped . But it is guaranteed that it is impossible to have a circular list of backing devices.(say loop2->loop1->loop0->loop2 is not possible), which guarantees that this can never deadlock. So this warning should be suppressed. It is very difficult to annotate lockdep not to warn here in the correct way. A simple way to silence lockdep could be to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some other real bugs. @@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, struct loop_device *lo = bdev->bd_disk->private_data; int err; - mutex_lock(&lo->lo_ctl_mutex); + mutex_lock_nested(&lo->lo_ctl_mutex, 1); switch (cmd) { case LOOP_SET_FD: err = loop_set_fd(lo, mode, bdev, arg); Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be a better solution. Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex held, so no lockdep annotation is required. If you do not like the special handling of the lo_ctl_mutex just for the LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside each of the individual ioctl handlers and I could send you another patch. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:33:41 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: fix circular locking in loop_clr_fd() With CONFIG_PROVE_LOCKING enabled $ losetup /dev/loop0 file $ losetup -o 32256 /dev/loop1 /dev/loop0 $ losetup -d /dev/loop1 $ losetup -d /dev/loop0 triggers a [ INFO: possible circular locking dependency detected ] I think this warning is a false positive. Open/close on a loop device acquires bd_mutex of the device before acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of a device, if backing file is a device and this is the last reference to the file being dropped . But it is guaranteed that it is impossible to have a circular list of backing devices.(say loop2->loop1->loop0->loop2 is not possible), which guarantees that this can never deadlock. So this warning should be suppressed. It is very difficult to annotate lockdep not to warn here in the correct way. A simple way to silence lockdep could be to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some other real bugs. @@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, struct loop_device *lo = bdev->bd_disk->private_data; int err; - mutex_lock(&lo->lo_ctl_mutex); + mutex_lock_nested(&lo->lo_ctl_mutex, 1); switch (cmd) { case LOOP_SET_FD: err = loop_set_fd(lo, mode, bdev, arg); Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be a better solution. Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex held, so no lockdep annotation is required. If you do not like the special handling of the lo_ctl_mutex just for the LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside each of the individual ioctl handlers and I could send you another patch. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:33:41 +01:00

drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() If the loop device is associated (lo->lo_state == Lo_bound), it will have a valid bdev pointed to by lo->lo_device. There is no reason to ever pass an additional block_device pointer. Signed-off-by: Ayan George <ayan.george@canonical.com> Cc: Phillip Susi <psusi@cfl.rr.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-09-21 10:02:13 +02:00

loop: fix circular locking in loop_clr_fd() With CONFIG_PROVE_LOCKING enabled $ losetup /dev/loop0 file $ losetup -o 32256 /dev/loop1 /dev/loop0 $ losetup -d /dev/loop1 $ losetup -d /dev/loop0 triggers a [ INFO: possible circular locking dependency detected ] I think this warning is a false positive. Open/close on a loop device acquires bd_mutex of the device before acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of a device, if backing file is a device and this is the last reference to the file being dropped . But it is guaranteed that it is impossible to have a circular list of backing devices.(say loop2->loop1->loop0->loop2 is not possible), which guarantees that this can never deadlock. So this warning should be suppressed. It is very difficult to annotate lockdep not to warn here in the correct way. A simple way to silence lockdep could be to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some other real bugs. @@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, struct loop_device *lo = bdev->bd_disk->private_data; int err; - mutex_lock(&lo->lo_ctl_mutex); + mutex_lock_nested(&lo->lo_ctl_mutex, 1); switch (cmd) { case LOOP_SET_FD: err = loop_set_fd(lo, mode, bdev, arg); Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be a better solution. Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex held, so no lockdep annotation is required. If you do not like the special handling of the lo_ctl_mutex just for the LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside each of the individual ioctl handlers and I could send you another patch. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:33:41 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: cleanup set_status interface 1) Anyone who has read access to loopdev has permission to call set_status and may change important parameters such as lo_offset, lo_sizelimit and so on, which contradicts to read access pattern and definitely equals to write access pattern. 2) Add lo_offset over i_size check to prevent blkdev_size overflow. ##Testcase_bagin #dd if=/dev/zero of=./file bs=1k count=1 #losetup /dev/loop0 ./file /* userspace_application */ struct loop_info64 loinf; fd = open("/dev/loop0", O_RDONLY); ioctl(fd, LOOP_GET_STATUS64, &loinf); /* Set offset to any value which is bigger than i_size, and sizelimit * to nonzero value*/ loinf.lo_offset = 4096*1024; loinf.lo_sizelimit = 1024; ioctl(fd, LOOP_SET_STATUS64, &loinf); /* After this loop device will have size similar to 0x7fffffffffxxxx */ #blockdev --getsz /dev/loop0 ##OUTPUT: 36028797018955968 ##Testcase_end [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-11-16 09:21:49 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2009-03-31 15:23:43 -07:00

block: loop: introduce ioctl command of LOOP_SET_DIRECT_IO If loop block is mounted via 'mount -o loop', it isn't easy to pass file descriptor opened as O_DIRECT, so this patch introduces a new command to support direct IO for this case. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:50 +08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] sem2mutex: drivers/block/loop.c Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-03-23 03:00:38 -08:00

loop: fix circular locking in loop_clr_fd() With CONFIG_PROVE_LOCKING enabled $ losetup /dev/loop0 file $ losetup -o 32256 /dev/loop1 /dev/loop0 $ losetup -d /dev/loop1 $ losetup -d /dev/loop0 triggers a [ INFO: possible circular locking dependency detected ] I think this warning is a false positive. Open/close on a loop device acquires bd_mutex of the device before acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of a device, if backing file is a device and this is the last reference to the file being dropped . But it is guaranteed that it is impossible to have a circular list of backing devices.(say loop2->loop1->loop0->loop2 is not possible), which guarantees that this can never deadlock. So this warning should be suppressed. It is very difficult to annotate lockdep not to warn here in the correct way. A simple way to silence lockdep could be to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some other real bugs. @@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode, struct loop_device *lo = bdev->bd_disk->private_data; int err; - mutex_lock(&lo->lo_ctl_mutex); + mutex_lock_nested(&lo->lo_ctl_mutex, 1); switch (cmd) { case LOOP_SET_FD: err = loop_set_fd(lo, mode, bdev, arg); Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be a better solution. Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex held, so no lockdep annotation is required. If you do not like the special handling of the lo_ctl_mutex just for the LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside each of the individual ioctl handlers and I could send you another patch. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-03-24 12:33:41 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] __user annotations: loop.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-10-10 22:48:27 +01:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

2009-03-31 15:23:43 -07:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block_device_operations->release() should return void The value passed is 0 in all but "it can never happen" cases (and those only in a couple of drivers) *and* it would've been lost on the way out anyway, even if something tried to pass something meaningful. Just don't bother. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-05-05 21:52:57 -04:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

loop: mutex already unlocked in loop_clr_fd() mount/1865 is trying to release lock (&lo->lo_ctl_mutex) at: but there are no more locks to release! mutex is already unlocked in loop_clr_fd(), we should not try to unlock it in lo_release() again. Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-04-07 13:48:21 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

loop: Flush possible running bios when loop device is released. When there are still queued bios and reference count drops to zero, loop device must flush all queued bios. Otherwise it can lead to situation that caller closes the device, but some bios are still running and endio() function call later OOpses when uses unallocated mempool. This happens for example when running dm-crypt over loop, here is typical oops backtrace: Oops: 0000 [#1] PREEMPT SMP EIP is at mempool_free+0x12/0x6b ... crypt_dec_pending+0x50/0x54 [dm_crypt] crypt_endio+0x9f/0xa7 [dm_crypt] crypt_endio+0x0/0xa7 [dm_crypt] bio_endio+0x2b/0x2e loop_thread+0x37a/0x3b1 do_lo_send_aops+0x0/0x165 autoremove_wake_function+0x0/0x33 loop_thread+0x0/0x3b1 kthread+0x3b/0x61 kthread+0x0/0x61 kernel_thread_helper+0x7/0x10 (But crash is reproducible with different dm targets running over loop device too.) Patch fixes it by flushing the bios in release call, reusing the flush mechanism for switching backing store. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2008-12-12 14:48:27 +01:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

loop: Flush possible running bios when loop device is released. When there are still queued bios and reference count drops to zero, loop device must flush all queued bios. Otherwise it can lead to situation that caller closes the device, but some bios are still running and endio() function call later OOpses when uses unallocated mempool. This happens for example when running dm-crypt over loop, here is typical oops backtrace: Oops: 0000 [#1] PREEMPT SMP EIP is at mempool_free+0x12/0x6b ... crypt_dec_pending+0x50/0x54 [dm_crypt] crypt_endio+0x9f/0xa7 [dm_crypt] crypt_endio+0x0/0xa7 [dm_crypt] bio_endio+0x2b/0x2e loop_thread+0x37a/0x3b1 do_lo_send_aops+0x0/0x165 autoremove_wake_function+0x0/0x33 loop_thread+0x0/0x3b1 kthread+0x3b/0x61 kthread+0x0/0x61 kernel_thread_helper+0x7/0x10 (But crash is reproducible with different dm targets running over loop device too.) Patch fixes it by flushing the bios in release call, reusing the flush mechanism for switching backing store. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2008-12-12 14:48:27 +01:00

drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd() If the loop device is associated (lo->lo_state == Lo_bound), it will have a valid bdev pointed to by lo->lo_device. There is no reason to ever pass an additional block_device pointer. Signed-off-by: Ayan George <ayan.george@canonical.com> Cc: Phillip Susi <psusi@cfl.rr.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-09-21 10:02:13 +02:00

loop: mutex already unlocked in loop_clr_fd() mount/1865 is trying to release lock (&lo->lo_ctl_mutex) at: but there are no more locks to release! mutex is already unlocked in loop_clr_fd(), we should not try to unlock it in lo_release() again. Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2009-04-07 13:48:21 +02:00

block_device_operations->release() should return void The value passed is 0 in all but "it can never happen" cases (and those only in a couple of drivers) *and* it would've been lost on the way out anyway, even if something tried to pass something meaningful. Just don't bother. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2013-05-05 21:52:57 -04:00

loop: Flush possible running bios when loop device is released. When there are still queued bios and reference count drops to zero, loop device must flush all queued bios. Otherwise it can lead to situation that caller closes the device, but some bios are still running and endio() function call later OOpses when uses unallocated mempool. This happens for example when running dm-crypt over loop, here is typical oops backtrace: Oops: 0000 [#1] PREEMPT SMP EIP is at mempool_free+0x12/0x6b ... crypt_dec_pending+0x50/0x54 [dm_crypt] crypt_endio+0x9f/0xa7 [dm_crypt] crypt_endio+0x0/0xa7 [dm_crypt] bio_endio+0x2b/0x2e loop_thread+0x37a/0x3b1 do_lo_send_aops+0x0/0x165 autoremove_wake_function+0x0/0x33 loop_thread+0x0/0x3b1 kthread+0x3b/0x61 kthread+0x0/0x61 kernel_thread_helper+0x7/0x10 (But crash is reproducible with different dm targets running over loop device too.) Patch fixes it by flushing the bios in release call, reusing the flush mechanism for switching backing store. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

2008-12-12 14:48:27 +01:00

Allow auto-destruction of loop devices This allows a flag to be set on loop devices so that when they are closed for the last time, they'll self-destruct. In general, so that we can automatically allocate loop devices (as with losetup -f) and have them disappear when we're done with them. In particular, right now, so that we can stop relying on the hackish special-case in umount(8) which kills off loop devices which were set up by 'mount -oloop'. That means we can stop putting crap in /etc/mtab which doesn't belong there, which means it can be a symlink to /proc/mounts, which means yet another writable file on the root filesystem is eliminated and the 'stateless' folks get happier... and OLPC trac #356 can be closed. The mount(8) side of that is at http://marc.info/?l=util-linux-ng&m=119362955431694&w=2 [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: David Woodhouse <dwmw2@infradead.org> Cc: Bernardo Innocenti <bernie@codewiz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2008-02-06 01:36:27 -08:00

[PATCH] sem2mutex: drivers/block/loop.c Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2006-03-23 03:00:38 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

const: make block_device_operations const Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2009-09-21 17:01:13 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

[PATCH] switch loop ioctl doesn't need BKL here Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2008-03-02 09:29:48 -05:00

[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6] Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop driver so that the loop header file doesn't need to be included. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2006-08-29 19:06:14 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: export module parameters Export 'max_loop' and 'max_part' parameters to sysfs so user can know that how many devices are allowed and how many partitions are supported. If 'max_loop' is 0, there is no restriction on the number of loop devices. User can create/use the devices as many as minor numbers available. If 'max_part' is 0, it means simply the device doesn't support partitioning. Also note that 'max_part' can be adjusted to power of 2 minus 1 form if needed. User should check this value after the module loading if he/she want to use that number correctly (i.e. fdisk, mknod, etc.). Signed-off-by: Namhyung Kim <namhyung@gmail.com> Cc: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-05-27 07:59:25 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: export module parameters Export 'max_loop' and 'max_part' parameters to sysfs so user can know that how many devices are allowed and how many partitions are supported. If 'max_loop' is 0, there is no restriction on the number of loop devices. User can create/use the devices as many as minor numbers available. If 'max_part' is 0, it means simply the device doesn't support partitioning. Also note that 'max_part' can be adjusted to power of 2 minus 1 form if needed. User should check this value after the module loading if he/she want to use that number correctly (i.e. fdisk, mknod, etc.). Signed-off-by: Namhyung Kim <namhyung@gmail.com> Cc: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-05-27 07:59:25 +02:00

2008-03-26 12:11:53 +01:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2014-12-31 13:22:57 +00:00

block: loop: convert to per-device workqueue Documentation/workqueue.txt: If there is dependency among multiple work items used during memory reclaim, they should be queued to separate wq each with WQ_MEM_RECLAIM. Loop devices can be stacked, so we have to convert to per-device workqueue. One example is Fedora live CD. Fixes: b5dd2f6047ca108001328aac0e8588edd15f1778 Cc: stable@vger.kernel.org (v4.0) Cc: Justin M. Forbes <jforbes@fedoraproject.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-05 19:49:54 +08:00

2014-12-31 13:22:57 +00:00

block: loop: convert to per-device workqueue Documentation/workqueue.txt: If there is dependency among multiple work items used during memory reclaim, they should be queued to separate wq each with WQ_MEM_RECLAIM. Loop devices can be stacked, so we have to convert to per-device workqueue. One example is Fedora live CD. Fixes: b5dd2f6047ca108001328aac0e8588edd15f1778 Cc: stable@vger.kernel.org (v4.0) Cc: Justin M. Forbes <jforbes@fedoraproject.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-05 19:49:54 +08:00

loop: don't try to use AIO for discards Fix a fat-fingered conversion to the req_op accessors, and also use a switch statement to make it more obvious what is being checked. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Dave Chinner <david@fromorbit.com> Fixes: c2df40 ("drivers: use req op accessor"); Reviewed-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:00 +02:00

2015-08-17 10:31:51 +08:00

loop: don't try to use AIO for discards Fix a fat-fingered conversion to the req_op accessors, and also use a switch statement to make it more obvious what is being checked. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Dave Chinner <david@fromorbit.com> Fixes: c2df40 ("drivers: use req op accessor"); Reviewed-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-08-04 16:10:00 +02:00

2015-08-17 10:31:51 +08:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

2014-12-31 13:22:57 +00:00

block, drivers, cgroup: use op_is_write helper instead of checking for REQ_WRITE We currently set REQ_WRITE/WRITE for all non READ IOs like discard, flush, writesame, etc. In the next patches where we no longer set up the op as a bitmap, we will not be able to detect a operation direction like writesame by testing if REQ_WRITE is set. This patch converts the drivers and cgroup to use the op_is_write helper. This should just cover the simple cases. I did dm, md and bcache in their own patches because they were more involved. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-06-05 14:31:45 -05:00

2014-12-31 13:22:57 +00:00

blk-mq: fix racy updates of rq->errors blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-09-27 21:01:50 +02:00

2014-12-31 13:22:57 +00:00

blk-mq: fix racy updates of rq->errors blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-09-27 21:01:50 +02:00

2014-12-31 13:22:57 +00:00

blk-mq: fix racy updates of rq->errors blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-09-27 21:01:50 +02:00

2014-12-31 13:22:57 +00:00

block: loop: say goodby to bio Switch to block request completely. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2014-12-31 13:22:58 +00:00

2014-12-31 13:22:57 +00:00

2015-08-17 10:31:51 +08:00

Merge branch 'for-4.4/core' into for-4.4/drivers Signed-off-by: Jens Axboe <axboe@fb.com>

2015-10-09 10:40:29 -06:00

2014-12-31 13:22:57 +00:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

2014-12-31 13:22:57 +00:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

2014-12-31 13:22:57 +00:00

block: loop: use kthread_work The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:48 +08:00

2014-12-31 13:22:57 +00:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

blk: fix wrong idr_pre_get() error check in loop.c The idr_pre_get() function never returns a value < 0. It returns 0 (no memory) or 1 (OK). Reported-by: Silva Paulo <psdasilva@yahoo.com> [ Rewrote Silva's patch, but attributing it to Silva anyway - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2012-07-14 15:39:58 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

blk: fix wrong idr_pre_get() error check in loop.c The idr_pre_get() function never returns a value < 0. It returns 0 (no memory) or 1 (OK). Reported-by: Silva Paulo <psdasilva@yahoo.com> [ Rewrote Silva's patch, but attributing it to Silva anyway - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2012-07-14 15:39:58 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

2013-10-15 14:14:38 -06:00

block/loop: convert to idr_alloc() Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-02-27 17:03:58 -08:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

block/loop: convert to idr_alloc() Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-02-27 17:03:58 -08:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

block/loop: convert to idr_alloc() Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-02-27 17:03:58 -08:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

block/loop: convert to idr_alloc() Convert to the much saner new idr interface. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-02-27 17:03:58 -08:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: fix error return code in loop_add() Fix to return a negative error code from the error handling case, as returned elsewhere in this function. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-03-22 08:59:19 -06:00

2014-12-31 13:22:57 +00:00

loop: fix crash if blk_alloc_queue fails loop: fix crash if blk_alloc_queue fails If blk_alloc_queue fails, loop_add cleans up, but it doesn't clean up the identifier allocated with idr_alloc. That causes crash on module unload in idr_for_each(&loop_index_idr, &loop_exit_cb, NULL); where we attempt to remove non-existed device with that id. BUG: unable to handle kernel NULL pointer dereference at 0000000000000380 IP: [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 PGD 43d399067 PUD 43d0ad067 PMD 0 Oops: 0000 [#1] PREEMPT SMP Modules linked in: loop(-) dm_snapshot dm_zero dm_mirror dm_region_hash dm_log dm_loop dm_mod ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_userspace cpufreq_stats cpufreq_ondemand cpufreq_conservative cpufreq_powersave spadfs fuse hid_generic usbhid hid raid0 md_mod dmi_sysfs nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd_usb_audio snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc lm85 hwmon_vid snd_hwdep snd_usbmidi_lib snd_rawmidi snd soundcore acpi_cpufreq ohci_hcd freq_table tg3 ehci_pci mperf ehci_hcd kvm_amd kvm sata_svw serverworks libphy libata ide_core k10temp usbcore hwmon microcode ptp pcspkr pps_core e100 skge mii usb_common i2c_piix4 floppy evdev rtc_cmos i2c_core processor but! ton unix CPU: 7 PID: 2735 Comm: rmmod Tainted: G W 3.10.15-devel #15 Hardware name: empty empty/S3992-E, BIOS 'V1.06 ' 06/09/2009 task: ffff88043d38e780 ti: ffff88043d21e000 task.ti: ffff88043d21e000 RIP: 0010:[<ffffffff812057c9>] [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 RSP: 0018:ffff88043d21fe10 EFLAGS: 00010282 RAX: ffffffffa05102e0 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88043ea82800 RDI: 0000000000000000 RBP: ffff88043d21fe48 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000000ff R13: 0000000000000080 R14: 0000000000000000 R15: ffff88043ea82800 FS: 00007ff646534700(0000) GS:ffff880447000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000380 CR3: 000000043e9bf000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffffffff8100aba4 0000000000000092 ffff88043d21fe48 ffff88043ea82800 00000000000000ff ffff88043d21fe98 0000000000000000 ffff88043d21fe60 ffffffffa05102b4 0000000000000000 ffff88043d21fe70 ffffffffa05102ec Call Trace: [<ffffffff8100aba4>] ? native_sched_clock+0x24/0x80 [<ffffffffa05102b4>] loop_remove+0x14/0x40 [loop] [<ffffffffa05102ec>] loop_exit_cb+0xc/0x10 [loop] [<ffffffff81217b74>] idr_for_each+0x104/0x190 [<ffffffffa05102e0>] ? loop_remove+0x40/0x40 [loop] [<ffffffff8109adc5>] ? trace_hardirqs_on_caller+0x105/0x1d0 [<ffffffffa05135dc>] loop_exit+0x34/0xa58 [loop] [<ffffffff810a98ea>] SyS_delete_module+0x13a/0x260 [<ffffffff81221d5e>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f Code: f0 4c 8b 6d f8 c9 c3 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 56 41 55 4c 8d af 80 00 00 00 41 54 53 48 89 fb 48 83 ec 18 <48> 83 bf 80 03 00 00 00 74 4d e8 98 fe ff ff 31 f6 48 c7 c7 20 RIP [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 RSP <ffff88043d21fe10> CR2: 0000000000000380 ---[ end trace 64ec069ec70f1309 ]--- Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org # 3.1+ Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-10-14 12:12:24 -04:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

2014-12-31 13:22:57 +00:00

2013-10-15 14:14:38 -06:00

block: loop: set QUEUE_FLAG_NOMERGES for request queue of loop It doesn't make sense to enable merge because the I/O submitted to backing file is handled page by page. Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-08-17 10:31:47 +08:00

loop: Make user notify for adding loop device failed There is no error number returned if loop driver fails in function alloc_disk to add new loop device. Add a correct error number to make user notify in this case. Signed-off-by: Minfei Huang <mnghuan@gmail.com> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2016-06-07 10:05:15 +08:00

2008-03-26 12:11:53 +01:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: always allow userspace partitions and optionally support automatic scanning Automatic partition scanning can be requested individually per loop device during its setup by setting LO_FLAGS_PARTSCAN. By default, no partition tables are scanned. Userspace can now always add and remove partitions from all loop devices, regardless if the in-kernel partition scanner is enabled or not. The needed partition minor numbers are allocated from the extended minors space, the main loop device numbers will continue to match the loop minors, regardless of the number of partitions used. # grep . /sys/class/block/loop1/loop/* /sys/block/loop1/loop/autoclear:0 /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img /sys/block/loop1/loop/offset:0 /sys/block/loop1/loop/partscan:1 /sys/block/loop1/loop/sizelimit:0 # ls -l /dev/loop* brw-rw---- 1 root disk 7, 0 Aug 14 20:22 /dev/loop0 brw-rw---- 1 root disk 7, 1 Aug 14 20:23 /dev/loop1 brw-rw---- 1 root disk 259, 0 Aug 14 20:23 /dev/loop1p1 brw-rw---- 1 root disk 259, 1 Aug 14 20:23 /dev/loop1p2 brw-rw---- 1 root disk 7, 99 Aug 14 20:23 /dev/loop99 brw-rw---- 1 root disk 259, 2 Aug 14 20:23 /dev/loop99p1 brw-rw---- 1 root disk 259, 3 Aug 14 20:23 /dev/loop99p2 crw------T 1 root root 10, 237 Aug 14 20:22 /dev/loop-control Cc: Karel Zak <kzak@redhat.com> Cc: Davidlohr Bueso <dave@gnu.org> Acked-By: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-08-23 20:12:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

2008-03-26 12:11:53 +01:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

2014-12-31 13:22:57 +00:00

loop: fix crash if blk_alloc_queue fails loop: fix crash if blk_alloc_queue fails If blk_alloc_queue fails, loop_add cleans up, but it doesn't clean up the identifier allocated with idr_alloc. That causes crash on module unload in idr_for_each(&loop_index_idr, &loop_exit_cb, NULL); where we attempt to remove non-existed device with that id. BUG: unable to handle kernel NULL pointer dereference at 0000000000000380 IP: [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 PGD 43d399067 PUD 43d0ad067 PMD 0 Oops: 0000 [#1] PREEMPT SMP Modules linked in: loop(-) dm_snapshot dm_zero dm_mirror dm_region_hash dm_log dm_loop dm_mod ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_userspace cpufreq_stats cpufreq_ondemand cpufreq_conservative cpufreq_powersave spadfs fuse hid_generic usbhid hid raid0 md_mod dmi_sysfs nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd_usb_audio snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc lm85 hwmon_vid snd_hwdep snd_usbmidi_lib snd_rawmidi snd soundcore acpi_cpufreq ohci_hcd freq_table tg3 ehci_pci mperf ehci_hcd kvm_amd kvm sata_svw serverworks libphy libata ide_core k10temp usbcore hwmon microcode ptp pcspkr pps_core e100 skge mii usb_common i2c_piix4 floppy evdev rtc_cmos i2c_core processor but! ton unix CPU: 7 PID: 2735 Comm: rmmod Tainted: G W 3.10.15-devel #15 Hardware name: empty empty/S3992-E, BIOS 'V1.06 ' 06/09/2009 task: ffff88043d38e780 ti: ffff88043d21e000 task.ti: ffff88043d21e000 RIP: 0010:[<ffffffff812057c9>] [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 RSP: 0018:ffff88043d21fe10 EFLAGS: 00010282 RAX: ffffffffa05102e0 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88043ea82800 RDI: 0000000000000000 RBP: ffff88043d21fe48 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000000ff R13: 0000000000000080 R14: 0000000000000000 R15: ffff88043ea82800 FS: 00007ff646534700(0000) GS:ffff880447000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000380 CR3: 000000043e9bf000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffffffff8100aba4 0000000000000092 ffff88043d21fe48 ffff88043ea82800 00000000000000ff ffff88043d21fe98 0000000000000000 ffff88043d21fe60 ffffffffa05102b4 0000000000000000 ffff88043d21fe70 ffffffffa05102ec Call Trace: [<ffffffff8100aba4>] ? native_sched_clock+0x24/0x80 [<ffffffffa05102b4>] loop_remove+0x14/0x40 [loop] [<ffffffffa05102ec>] loop_exit_cb+0xc/0x10 [loop] [<ffffffff81217b74>] idr_for_each+0x104/0x190 [<ffffffffa05102e0>] ? loop_remove+0x40/0x40 [loop] [<ffffffff8109adc5>] ? trace_hardirqs_on_caller+0x105/0x1d0 [<ffffffffa05135dc>] loop_exit+0x34/0xa58 [loop] [<ffffffff810a98ea>] SyS_delete_module+0x13a/0x260 [<ffffffff81221d5e>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f Code: f0 4c 8b 6d f8 c9 c3 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 56 41 55 4c 8d af 80 00 00 00 41 54 53 48 89 fb 48 83 ec 18 <48> 83 bf 80 03 00 00 00 74 4d e8 98 fe ff ff 31 f6 48 c7 c7 20 RIP [<ffffffff812057c9>] del_gendisk+0x19/0x2d0 RSP <ffff88043d21fe10> CR2: 0000000000000380 ---[ end trace 64ec069ec70f1309 ]--- Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org # 3.1+ Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-10-14 12:12:24 -04:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

block: destroy bdi before blockdev is unregistered. Because of the peculiar way that md devices are created (automatically when the device node is opened), a new device can be created and registered immediately after the blk_unregister_region(disk_devt(disk), disk->minors); call in del_gendisk(). Therefore it is important that all visible artifacts of the previous device are removed before this call. In particular, the 'bdi'. Since: commit c4db59d31e39ea067c32163ac961e9c80198fd37 Author: Christoph Hellwig <hch@lst.de> fs: don't reassign dirty inodes to default_backing_dev_info moved the device_unregister(bdi->dev); call from bdi_unregister() to bdi_destroy() it has been quite easy to lose a race and have a new (e.g.) "md127" be created after the blk_unregister_region() call and before bdi_destroy() is ultimately called by the final 'put_disk', which must come after del_gendisk(). The new device finds that the bdi name is already registered in sysfs and complains > [ 9627.630029] WARNING: CPU: 18 PID: 3330 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x5a/0x70() > [ 9627.630032] sysfs: cannot create duplicate filename '/devices/virtual/bdi/9:127' We can fix this by moving the bdi_destroy() call out of blk_release_queue() (which can happen very late when a refcount reaches zero) and into blk_cleanup_queue() - which happens exactly when the md device driver calls it. Then it is only necessary for md to call blk_cleanup_queue() before del_gendisk(). As loop.c devices are also created on demand by opening the device node, we make the same change there. Fixes: c4db59d31e39ea067c32163ac961e9c80198fd37 Reported-by: Azat Khuzhin <a3at.mail@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org (v4.0) Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-04-27 14:12:22 +10:00

2014-12-31 13:22:57 +00:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

fix deadlock in loop.c ... doh Jeremy Fitzhardinge noted that the recent loop.c cleanups worked, but cause lockdep to complain. Ouch. OK, the deadlock is real and yes, I'm an idiot. Speaking of which, we probably want to s/lock/pin/ in drivers/base/map.c to avoid such brainos again. And yes, this stuff needs clear documentation. Will try to put one together once I get some sleep... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-13 05:52:32 -04:00

fix the dynamic allocation and probe in loop.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Ken Chen <kenchen@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-12 16:23:15 -04:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

block: fix a probe argument to blk_register_region The probe function is supposed to return NULL on failure (as we can see in kobj_lookup: kobj = probe(dev, index, data); ... if (kobj) return kobj; However, in loop and brd, it returns negative error from ERR_PTR. This causes a crash if we simulate disk allocation failure and run less -f /dev/loop0 because the negative number is interpreted as a pointer: BUG: unable to handle kernel NULL pointer dereference at 00000000000002b4 IP: [<ffffffff8118b188>] __blkdev_get+0x28/0x450 PGD 23c677067 PUD 23d6d1067 PMD 0 Oops: 0000 [#1] PREEMPT SMP Modules linked in: loop hpfs nvidia(PO) ip6table_filter ip6_tables uvesafb cfbcopyarea cfbimgblt cfbfillrect fbcon font bitblit fbcon_rotate fbcon_cw fbcon_ud fbcon_ccw softcursor fb fbdev msr ipt_MASQUERADE iptable_nat nf_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp llc tun ipv6 cpufreq_stats cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_conservative hid_generic spadfs usbhid hid fuse raid0 snd_usb_audio snd_pcm_oss snd_mixer_oss md_mod snd_pcm snd_timer snd_page_alloc snd_hwdep snd_usbmidi_lib dmi_sysfs snd_rawmidi nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack snd soundcore lm85 hwmon_vid ohci_hcd ehci_pci ehci_hcd serverworks sata_svw libata acpi_cpufreq freq_table mperf ide_core usbcore kvm_amd kvm tg3 i2c_piix4 libphy microcode e100 usb_common ptp skge i2c_core pcspkr k10temp evdev floppy hwmon pps_core mii rtc_cmos button processor unix [last unloaded: nvidia] CPU: 1 PID: 6831 Comm: less Tainted: P W O 3.10.15-devel #18 Hardware name: empty empty/S3992-E, BIOS 'V1.06 ' 06/09/2009 task: ffff880203cc6bc0 ti: ffff88023e47c000 task.ti: ffff88023e47c000 RIP: 0010:[<ffffffff8118b188>] [<ffffffff8118b188>] __blkdev_get+0x28/0x450 RSP: 0018:ffff88023e47dbd8 EFLAGS: 00010286 RAX: ffffffffffffff74 RBX: ffffffffffffff74 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88023e47dc18 R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88023f519658 R13: ffffffff8118c300 R14: 0000000000000000 R15: ffff88023f519640 FS: 00007f2070bf7700(0000) GS:ffff880247400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000002b4 CR3: 000000023da1d000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: 0000000000000002 0000001d00000000 000000003e47dc50 ffff88023f519640 ffff88043d5bb668 ffffffff8118c300 ffff88023d683550 ffff88023e47de60 ffff88023e47dc98 ffffffff8118c10d 0000001d81605698 0000000000000292 Call Trace: [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60 [<ffffffff8118c10d>] blkdev_get+0x1dd/0x370 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50 [<ffffffff8118c300>] ? blkdev_get_by_dev+0x60/0x60 [<ffffffff8118c365>] blkdev_open+0x65/0x80 [<ffffffff8114d12e>] do_dentry_open.isra.18+0x23e/0x2f0 [<ffffffff8114d214>] finish_open+0x34/0x50 [<ffffffff8115e122>] do_last.isra.62+0x2d2/0xc50 [<ffffffff8115eb58>] path_openat.isra.63+0xb8/0x4d0 [<ffffffff81115a8e>] ? might_fault+0x4e/0xa0 [<ffffffff8115f4f0>] do_filp_open+0x40/0x90 [<ffffffff813cea6c>] ? _raw_spin_unlock+0x2c/0x50 [<ffffffff8116db85>] ? __alloc_fd+0xa5/0x1f0 [<ffffffff8114e45f>] do_sys_open+0xef/0x1d0 [<ffffffff8114e559>] SyS_open+0x19/0x20 [<ffffffff813cff16>] system_call_fastpath+0x1a/0x1f Code: 44 00 00 55 48 89 e5 41 57 49 89 ff 41 56 41 89 d6 41 55 41 54 4c 8d 67 18 53 48 83 ec 18 89 75 cc e9 f2 00 00 00 0f 1f 44 00 00 <48> 8b 80 40 03 00 00 48 89 df 4c 8b 68 58 e8 d5 a4 07 00 44 89 RIP [<ffffffff8118b188>] __blkdev_get+0x28/0x450 RSP <ffff88023e47dbd8> CR2: 00000000000002b4 ---[ end trace bb7f32dbf02398dc ]--- The brd change should be backported to stable kernels starting with 2.6.25. The loop change should be backported to stable kernels starting with 2.6.22. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org # 2.6.22+ Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-10-14 12:13:24 -04:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

fix the dynamic allocation and probe in loop.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Ken Chen <kenchen@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-12 16:23:15 -04:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

block: loop: don't hold lo_ctl_mutex in lo_open The lo_ctl_mutex is held for running all ioctl handlers, and in some ioctl handlers, ioctl_by_bdev(BLKRRPART) is called for rereading partitions, which requires bd_mutex. So it is easy to cause failure because trylock(bd_mutex) may fail inside blkdev_reread_part(), and follows the lock context: blkid or other application: ->open() ->mutex_lock(bd_mutex) ->lo_open() ->mutex_lock(lo_ctl_mutex) losetup(set fd ioctl): ->mutex_lock(lo_ctl_mutex) ->ioctl_by_bdev(BLKRRPART) ->trylock(bd_mutex) This patch trys to eliminate the ABBA lock dependency by removing lo_ctl_mutext in lo_open() with the following approach: 1) make lo_refcnt as atomic_t and avoid acquiring lo_ctl_mutex in lo_open(): - for open vs. add/del loop, no any problem because of loop_index_mutex - freeze request queue during clr_fd, so I/O can't come until clearing fd is completed, like the effect of holding lo_ctl_mutex in lo_open - both open() and release() have been serialized by bd_mutex already 2) don't hold lo_ctl_mutex for decreasing/checking lo_refcnt in lo_release(), then lo_ctl_mutex is only required for the last release. Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Jarod Wilson <jarod@redhat.com> Acked-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>

2015-05-06 12:26:23 +08:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

2008-03-26 12:11:53 +01:00

loop: export module parameters Export 'max_loop' and 'max_part' parameters to sysfs so user can know that how many devices are allowed and how many partitions are supported. If 'max_loop' is 0, there is no restriction on the number of loop devices. User can create/use the devices as many as minor numbers available. If 'max_part' is 0, it means simply the device doesn't support partitioning. Also note that 'max_part' can be adjusted to power of 2 minus 1 form if needed. User should check this value after the module loading if he/she want to use that number correctly (i.e. fdisk, mknod, etc.). Signed-off-by: Namhyung Kim <namhyung@gmail.com> Cc: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-05-27 07:59:25 +02:00

2008-03-26 12:11:53 +01:00

loop: export module parameters Export 'max_loop' and 'max_part' parameters to sysfs so user can know that how many devices are allowed and how many partitions are supported. If 'max_loop' is 0, there is no restriction on the number of loop devices. User can create/use the devices as many as minor numbers available. If 'max_part' is 0, it means simply the device doesn't support partitioning. Also note that 'max_part' can be adjusted to power of 2 minus 1 form if needed. User should check this value after the module loading if he/she want to use that number correctly (i.e. fdisk, mknod, etc.). Signed-off-by: Namhyung Kim <namhyung@gmail.com> Cc: Laurent Vivier <Laurent.Vivier@bull.net> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-05-27 07:59:25 +02:00

loopdev: remove an user triggerable oops When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:49 -08:00

loop: limit 'max_part' module param to DISK_MAX_PARTS The 'max_part' parameter controls the number of maximum partition a loop block device can have. However if a user specifies very large value it would exceed the limitation of device minor number and can cause a kernel panic (or, at least, produce invalid device nodes in some cases). On my desktop system, following command kills the kernel. On qemu, it triggers similar oops but the kernel was alive: $ sudo modprobe loop max_part0000 ------------[ cut here ]------------ kernel BUG at /media/Linux_Data/project/linux/fs/sysfs/group.c:65! invalid opcode: 0000 [#1] SMP last sysfs file: CPU 0 Modules linked in: loop(+) Pid: 43, comm: insmod Tainted: G W 2.6.39-qemu+ #155 Bochs Bochs RIP: 0010:[<ffffffff8113ce61>] [<ffffffff8113ce61>] internal_create_group= +0x2a/0x170 RSP: 0018:ffff880007b3fde8 EFLAGS: 00000246 RAX: 00000000ffffffef RBX: ffff880007b3d878 RCX: 00000000000007b4 RDX: ffffffff8152da50 RSI: 0000000000000000 RDI: ffff880007b3d878 RBP: ffff880007b3fe38 R08: ffff880007b3fde8 R09: 0000000000000000 R10: ffff88000783b4a8 R11: ffff880007b3d878 R12: ffffffff8152da50 R13: ffff880007b3d868 R14: 0000000000000000 R15: ffff880007b3d800 FS: 0000000002137880(0063) GS:ffff880007c00000(0000) knlGS:00000000000000= 00 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000422680 CR3: 0000000007b50000 CR4: 00000000000006b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000 Process insmod (pid: 43, threadinfo ffff880007b3e000, task ffff880007afb9c= 0) Stack: ffff880007b3fe58 ffffffff811e66dd ffff880007b3fe58 ffffffff811e570b 0000000000000010 ffff880007b3d800 ffff880007a7b390 ffff880007b3d868 0000000000400920 ffff880007b3d800 ffff880007b3fe48 ffffffff8113cfc8 Call Trace: [<ffffffff811e66dd>] ? device_add+0x4bc/0x5af [<ffffffff811e570b>] ? dev_set_name+0x3c/0x3e [<ffffffff8113cfc8>] sysfs_create_group+0xe/0x12 [<ffffffff810b420e>] blk_trace_init_sysfs+0x14/0x16 [<ffffffff8116a090>] blk_register_queue+0x47/0xf7 [<ffffffff8116f527>] add_disk+0xdf/0x290 [<ffffffffa00060eb>] loop_init+0xeb/0x1b8 [loop] [<ffffffffa0006000>] ? 0xffffffffa0005fff [<ffffffff8100020a>] do_one_initcall+0x7a/0x12e [<ffffffff81096804>] sys_init_module+0x9c/0x1e0 [<ffffffff813329bb>] system_call_fastpath+0x16/0x1b Code: c3 55 48 89 e5 41 57 41 56 41 89 f6 41 55 41 54 49 89 d4 53 48 89 fb= 48 83 ec 28 48 85 ff 74 0b 85 f6 75 0b 48 83 7f 30 00 75 14 <0f> 0b eb fe = 48 83 7f 30 00 b9 ea ff ff ff 0f 84 18 01 00 00 49 RIP [<ffffffff8113ce61>] internal_create_group+0x2a/0x170 RSP <ffff880007b3fde8> ---[ end trace a123eb592043acad ]--- Signed-off-by: Namhyung Kim <namhyung@gmail.com> Cc: Laurent Vivier <Laurent.Vivier@bull.net> Cc: stable@kernel.org Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-05-24 16:48:54 +02:00

loopdev: remove an user triggerable oops When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:49 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: add BLK_DEV_LOOP_MIN_COUNT=%i to allow distros 0 pre-allocated loop devices Instead of unconditionally creating a fixed number of dead loop devices which need to be investigated by storage handling services, even when they are never used, we allow distros start with 0 loop devices and have losetup(8) and similar switch to the dynamic /dev/loop-control interface instead of searching /dev/loop%i for free devices. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

2011-05-24 16:48:55 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add BLK_DEV_LOOP_MIN_COUNT=%i to allow distros 0 pre-allocated loop devices Instead of unconditionally creating a fixed number of dead loop devices which need to be investigated by storage handling services, even when they are never used, we allow distros start with 0 loop devices and have losetup(8) and similar switch to the dynamic /dev/loop-control interface instead of searching /dev/loop%i for free devices. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

2011-05-24 16:48:55 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loopdev: remove an user triggerable oops When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:49 -08:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: add BLK_DEV_LOOP_MIN_COUNT=%i to allow distros 0 pre-allocated loop devices Instead of unconditionally creating a fixed number of dead loop devices which need to be investigated by storage handling services, even when they are never used, we allow distros start with 0 loop devices and have losetup(8) and similar switch to the dynamic /dev/loop-control interface instead of searching /dev/loop%i for free devices. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loopdev: remove an user triggerable oops When loopdev is built as module and we pass an invalid parameter, loop_init() will return directly without deregister misc device, which will cause an oops when insert loop module next time because we left some garbage in the misc device list. Test case: sudo modprobe loop max_part=1024 (failed due to invalid parameter) sudo modprobe loop (oops) Clean up nicely to avoid such oops. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: M. Hindess <hindessm@uk.ibm.com> Cc: Nikanth Karthikesan <knikanth@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>

2013-02-21 15:16:49 -08:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2011-05-24 16:48:55 +02:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

loop: replace linked list of allocated devices with an idr index Replace the linked list, that keeps track of allocated devices, with an idr index to allow a more efficient lookup of devices. Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

remove artificial software max_loop limit Remove artificial maximum 256 loop device that can be created due to a legacy device number limit. Searching through lkml archive, there are several instances where users complained about the artificial limit that the loop driver impose. There is no reason to have such limit. This patch rid the limit entirely and make loop device and associated block queue instantiation on demand. With on-demand instantiation, it also gives the benefit of not wasting memory if these devices are not in use (compare to current implementation that always create 8 loop devices), a net improvement in both areas. This version is both tested with creation of large number of loop devices and is compatible with existing losetup/mount user land tools. There are a number of people who worked on this and provided valuable suggestions, in no particular order, by: Jens Axboe Jan Engelhardt Christoph Hellwig Thomas M Signed-off-by: Ken Chen <kenchen@google.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-05-08 00:28:20 -07:00

loop: preallocate eight loop devices The kernel on-demand loop device instantiation breaks several user space tools as the tools are not ready to cope with the "on-demand feature". Fix it by instantiate default 8 loop devices and also reinstate max_loop module parameter. Signed-off-by: Ken Chen <kenchen@google.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-06-08 13:46:44 -07:00

unregister_blkdev() delete redundant messages in callers No need to warn unregister_blkdev() failure by the callers. (The previous patch makes unregister_blkdev() print error message in error case) Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2007-07-17 04:03:46 -07:00

loop: add management interface for on-demand device allocation Loop devices today have a fixed pre-allocated number of usually 8. The number can only be changed at module init time. To find a free device to use, /dev/loop%i needs to be scanned, and all devices need to be opened until a free one is possibly found. This adds a new /dev/loop-control device node, that allows to dynamically find or allocate a free device, and to add and remove loop devices from the running system: LOOP_CTL_ADD adds a specific device. Arg is the number of the device. It returns the device i or a negative error code. LOOP_CTL_REMOVE removes a specific device, Arg is the number the device. It returns the device i or a negative error code. LOOP_CTL_GET_FREE finds the next unbound device or allocates a new one. No arg is given. It returns the device i or a negative error code. The loop kernel module gets automatically loaded when /dev/loop-control is accessed the first time. The alias specified in the module, instructs udev to create this 'dead' device node, even when the module is not loaded. Example: cfd = open("/dev/loop-control", O_RDWR); # add a new specific loop device err = ioctl(cfd, LOOP_CTL_ADD, devnr); # remove a specific loop device err = ioctl(cfd, LOOP_CTL_REMOVE, devnr); # find or allocate a free loop device to use devnr = ioctl(cfd, LOOP_CTL_GET_FREE); sprintf(loopname, "/dev/loop%i", devnr); ffd = open("backing-file", O_RDWR); lfd = open(loopname, O_RDWR); err = ioctl(lfd, LOOP_SET_FD, ffd); Cc: Tejun Heo <tj@kernel.org> Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2011-07-31 22:08:04 +02:00

Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!

2005-04-16 15:20:36 -07:00

2052 lines 50 KiB Raw Permalink Normal View History

2052 lines

50 KiB

Raw Permalink Normal View History