kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-16 22:39:48 +00:00
Code Issues Releases Packages Activity
linux/fs/sysfs/file.c

759 lines
19 KiB
Raw Normal View History

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
sysfs: add copyrights Sysfs has gone through considerable amount of reimplementation. Add copyrights. Any objections? :-) Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 17:31:38 +09:00
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
driver core: debug for bad dev_attr_show() return value. Try to find the culprit who caused http://bugzilla.kernel.org/show_bug.cgi?id=10150 Cc: <balajirrao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-04 15:09:07 -08:00
SYSFS: Explicitly include required header file slab.h. After an experimental deletion of the unnecessary inclusion of <linux/slab.h> from the header file <linux/percpu.h>, the following files under fs/sysfs were exposed as needing to explicitly include <linux/slab.h>. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-13 22:41:52 -04:00
sysfs: don't call notify_change sysfs_chmod_file() calls notify_change() to change the permission bits on a sysfs file. Replace with explicit call to sysfs_setattr() and fsnotify_change(). This is equivalent, except that security_inode_setattr() is not called. This function is called by drivers, so the security checks do not make any sense. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-06-16 13:46:47 +02:00
[PATCH] remove duplicate get_dentry functions in various places Various filesystem drivers have grown a get_dentry() function that's a duplicate of lookup_one_len, except that it doesn't take a maximum length argument and doesn't check for \0 or / in the passed in filename. Switch all these places to use lookup_one_len. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Greg KH <greg@kroah.com> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 00:09:12 -07:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
Driver core: fix race in sysfs between sysfs_remove_file() and read()/write() This patch prevents a race between IO and removing a file from sysfs. It introduces a list of sysfs_buffers associated with a file at the inode. Upon removal of a file the list is walked and the buffers marked orphaned. IO to orphaned buffers fails with -ENODEV. The driver can safely free associated data structures or be unloaded. Signed-off-by: Oliver Neukum <oliver@neukum.name> Acked-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:52:44 +01:00
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +00:00
sysfs: crash debugging Print the name of the last-accessed sysfs file when we oops, to help track down oopses which occur in sysfs store/read handlers. Because these oopses tend to not leave any trace of the offending code in the stack traces. Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-24 16:11:54 -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
sysfs: crash debugging Print the name of the last-accessed sysfs file when we oops, to help track down oopses which occur in sysfs store/read handlers. Because these oopses tend to not leave any trace of the offending code in the stack traces. Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-24 16:11:54 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: remove SPIN_LOCK_UNLOCKED SPIN_LOCK_UNLOCKED is deprecated, use DEFINE_SPINLOCK instead Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Tejun Heo <teheo@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-21 14:55:19 -08:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill attribute file orphaning Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
Driver core: Constify struct sysfs_ops in struct kobj_type Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-19 02:58:23 +01:00
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +00:00
sysfs: kill attribute file orphaning Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill attribute file orphaning Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
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
sysfs: error handling in sysfs, fill_read_buffer() if a driver returns an error in fill_read_buffer(), the buffer will be marked as filled. Subsequent reads will return eof. But there is no data because of an error, not because it has been read. Not marking the buffer filled is the obvious fix. Signed-off-by: Oliver Neukum <oliver@neukum.name> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-02 08:48:08 +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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
Driver core: Constify struct sysfs_ops in struct kobj_type Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-19 02:58:23 +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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: fix off-by-one error in fill_read_buffer() I found that there is a off-by-one problem in the following code. Version: 2.6.24-rc2 File: fs/sysfs/file.c:118-122 Function: fill_read_buffer -------------------------------------------------------------------- count = ops->show(kobj, attr_sd->s_attr.attr, buffer->page); sysfs_put_active_two(attr_sd); BUG_ON(count > (ssize_t)PAGE_SIZE); -------------------------------------------------------------------- Because according to the specification of the sysfs and the implement of the show methods, the show methods return the number of bytes which would be generated for the given input, excluding the trailing null.So if the return value of the show methods equals PAGE_SIZE - 1, the buffer is full in fact. And if the return value equals PAGE_SIZE, the resulting string was already truncated,or buffer overflow occurred. This patch fixes an off-by-one error in fill_read_buffer. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Tejun Heo <teheo@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-21 14:55:19 -08:00
driver core: debug for bad dev_attr_show() return value. Try to find the culprit who caused http://bugzilla.kernel.org/show_bug.cgi?id=10150 Cc: <balajirrao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-03-04 15:09:07 -08:00
sysfs: error handling in sysfs, fill_read_buffer() if a driver returns an error in fill_read_buffer(), the buffer will be marked as filled. Subsequent reads will return eof. But there is no data because of an error, not because it has been read. Not marking the buffer filled is the obvious fix. Signed-off-by: Oliver Neukum <oliver@neukum.name> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-02 08:48:08 +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
sysfs: error handling in sysfs, fill_read_buffer() if a driver returns an error in fill_read_buffer(), the buffer will be marked as filled. Subsequent reads will return eof. But there is no data because of an error, not because it has been read. Not marking the buffer filled is the obvious fix. Signed-off-by: Oliver Neukum <oliver@neukum.name> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-02 08:48:08 +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
sysfs: error handling in sysfs, fill_read_buffer() if a driver returns an error in fill_read_buffer(), the buffer will be marked as filled. Subsequent reads will return eof. But there is no data because of an error, not because it has been read. Not marking the buffer filled is the obvious fix. Signed-off-by: Oliver Neukum <oliver@neukum.name> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-02 08:48:08 +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
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +00:00
sysfs: refill attribute buffer when reading from offset 0 Requiring userspace to close and re-open sysfs attributes has been the policy since before 2.6.12. It allows userspace to get a consistent snapshot of kernel state and consume it with incremental reads and seeks. Now, if the file position is zero the kernel assumes userspace wants to see the new value. The application for this change is to allow a userspace RAID metadata handler to check the state of an array without causing any memory allocations. Thus not causing writeback to a raid array that might be blocked waiting for userspace to take action. Cc: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-07 15:35:01 -07:00
sysfs: kill attribute file orphaning Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
[PATCH] sysfs: reinstate exclusion between method calls and attribute unregistration This patch (as869) reinstates the mutual exclusion between sysfs attribute method calls and attribute unregistration. The previously-reported deadlocks have been fixed, and this exclusion is by far the simplest way to avoid races during driver unbinding. The check for orphaned read-buffers has been moved down slightly, so that the remainder of a partially-read buffer will still be available to userspace even after the attribute has been unregistered. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:51:28 -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] pr_debug: sysfs: use size_t length modifier in pr_debug format arguments sysfs: use size_t length modifier in pr_debug format arguments Signed-off-by: Zach Brown <zach.brown@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03 01:16:06 -07:00
fs: replace remaining __FUNCTION__ occurrences __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 00:55:09 -07:00
use simple_read_from_buffer() in fs/ Cleanup using simple_read_from_buffer() in binfmt_misc, configfs, and sysfs. Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Joel Becker <joel.becker@oracle.com> 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>
2007-05-09 02:33:32 -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
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +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
[PATCH] DocBook: fix some descriptions Some KernelDoc descriptions are updated to match the current code. No code changes. Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:26 -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] sysfs: zero terminate sysfs write buffers No one should be writing a PAGE_SIZE worth of data to a normal sysfs file, so properly terminate the buffer. Thanks to Al Viro for pointing out my supidity here. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 15:37:06 -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
sysfs: sysfs_write_file() writes zero terminated data since most of the files in sysfs are text files, it would be nice, if the "store" function called during sysfs_write_file() gets a zero terminated string / data. The current implementation seems not to ensure this. (But only if it is the first time the zeroed buffer page is allocated.) So the buffer can be scanned by sscanf() easily, for example. This patch simply sets a \0 char behind the data in buffer->page. Signed-off-by: Thomas Maier <balagi@justmail.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-22 19:17:47 +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] DocBook: update comments This patch updates some comments to match code changes. Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 22:05:21 -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] DocBook: update comments This patch updates some comments to match code changes. Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 22:05:21 -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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
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
sysfs: make sysfs_dirent->s_element a union Make sd->s_element a union of sysfs_elem_{dir|symlink|attr|bin_attr} and rename it to s_elem. This is to achieve... * some level of type checking : changing symlink to point to sysfs_dirent instead of kobject is much safer and less painful now. * easier / standardized dereferencing * allow sysfs_elem_* to contain more than one entry Where possible, pointer is obtained by directly deferencing from sd instead of going through other entities. This reduces dependencies to dentry, inode and kobject. to_attr() and to_bin_attr() are unused now and removed. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:15 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
Driver core: Constify struct sysfs_ops in struct kobj_type Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-19 02:58:23 +01:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
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
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +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
[PATCH] sysfs: change uses of f_{dentry, vfsmnt} to use f_path Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the sysfs filesystem code. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 02:36:36 -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
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +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
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
Driver core: fix race in sysfs between sysfs_remove_file() and read()/write() This patch prevents a race between IO and removing a file from sysfs. It introduces a list of sysfs_buffers associated with a file at the inode. Upon removal of a file the list is walked and the buffers marked orphaned. IO to orphaned buffers fails with -ENODEV. The driver can safely free associated data structures or be unloaded. Signed-off-by: Oliver Neukum <oliver@neukum.name> Acked-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:52:44 +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
sysfs: make sysfs_dirent->s_element a union Make sd->s_element a union of sysfs_elem_{dir|symlink|attr|bin_attr} and rename it to s_elem. This is to achieve... * some level of type checking : changing symlink to point to sysfs_dirent instead of kobject is much safer and less painful now. * easier / standardized dereferencing * allow sysfs_elem_* to contain more than one entry Where possible, pointer is obtained by directly deferencing from sd instead of going through other entities. This reduces dependencies to dentry, inode and kobject. to_attr() and to_bin_attr() are unused now and removed. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:15 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +01:00
Driver core: Constify struct sysfs_ops in struct kobj_type Constify struct sysfs_ops. This is part of the ops structure constification effort started by Arjan van de Ven et al. Benefits of this constification: * prevents modification of data that is shared (referenced) by many other structure instances at runtime * detects/prevents accidental (but not intentional) modification attempts on archs that enforce read-only kernel data at runtime * potentially better optimized code as the compiler can assume that the const data cannot be changed * the compiler/linker move const data into .rodata and therefore exclude them from false sharing Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: David Teigland <teigland@redhat.com> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Hans J. Koch <hjk@linutronix.de> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-19 02:58:23 +01:00
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +01:00
sysfs: crash debugging Print the name of the last-accessed sysfs file when we oops, to help track down oopses which occur in sysfs store/read handlers. Because these oopses tend to not leave any trace of the offending code in the stack traces. Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-24 16:11:54 -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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
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
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +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
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +01:00
Use WARN() in fs/sysfs Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes part of the warning section for better reporting/collection. Also, with this, one fo the if() sections collapses entirely into the WARN(). Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 19:45:41 -07:00
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +01:00
sysfs: kill unnecessary attribute->owner sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:17 +09:00
Driver Core: kill subsys_attribute and default sysfs ops Remove the no longer needed subsys_attributes, they are all converted to the more sensical kobj_attributes. There is no longer a magic fallback in sysfs attribute operations, all kobjects which create simple attributes need explicitely a ktype assigned, which tells the core what was intended here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-11-02 13:47:53 +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
sysfs: kill unnecessary attribute->owner sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:17 +09:00
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
sysfs: kill unnecessary attribute->owner sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:17 +09:00
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
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
[PATCH] sysfs: kzalloc conversion this converts fs/sysfs to kzalloc() usage. compile tested with make allyesconfig Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-22 11:18:15 +01:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: kill unnecessary attribute->owner sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:17 +09:00
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
sysfs/file.c - use mutex instead of semaphore Use mutex instead of semaphore in sysfs/file.c : sys_buffer. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-26 11:03:54 +00:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill unnecessary sysfs_get() in open paths There's no reason to get an extra reference to sysfs_dirent for an open file. Open file has a reference to the dentry which in turn has a reference to sysfs_dirent. This is fairly obvious as otherwise open itself won't be able to access the sysfs_dirent. Kill the extra sysfs_get() and matching sysfs_put(). Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:10 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill unnecessary attribute->owner sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:17 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -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
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
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
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill attribute file orphaning Now that sysfs_dirent can be disconnected from kobject on deletion, there is no need to orphan each attribute files. All [bin_]attribute nodes are automatically orphaned when the parent node is deleted. Kill attribute file orphaning. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
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
sysfs: implement sysfs_open_dirent Implement sysfs_open_dirent which represents an open file (attribute) sysfs_dirent. A file sysfs_dirent with one or more open files have one sysfs_dirent and all sysfs_buffers (one for each open instance) are linked to it. sysfs_open_dirent doesn't actually do anything yet but will be used to off-load things which are specific for open file sysfs_dirent from it. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: kill unnecessary NULL pointer check in sysfs_release() In sysfs_release(), sysfs_buffer pointed to by filp->private_data is guaranteed to exist. Kill the unnecessary NULL check. This also makes the code more consistent with the counterpart in fs/sysfs/bin.c. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:10 +09:00
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] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: refill attribute buffer when reading from offset 0 Requiring userspace to close and re-open sysfs attributes has been the policy since before 2.6.12. It allows userspace to get a consistent snapshot of kernel state and consume it with incremental reads and seeks. Now, if the file position is zero the kernel assumes userspace wants to see the new value. The application for this change is to allow a userspace RAID metadata handler to check the state of an array without causing any memory allocations. Thus not causing writeback to a raid array that might be blocked waiting for userspace to take action. Cc: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-07 15:35:01 -07:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: Fix typos in fs/sysfs/file.c Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-10 13:51:07 -07:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: Remove sysfs_get/put_active_two It turns out that holding an active reference on a directory is pointless. The purpose of the active references are to allows us to block when removing sysfs entries that have custom methods so we don't remove modules while running modular code and to keep those custom methods from accessing data structures after the files have been removed. Further sysfs_remove_dir remove all elements in the directory before removing the directory itself, so there is no chance we will remove a directory with active children. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:18:38 -08:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: move sysfs file poll implementation to sysfs_open_dirent Sysfs file poll implementation is scattered over sysfs and kobject. Event numbering is done in sysfs_dirent but wait itself is done on kobject. This not only unecessarily bloats both kobject and sysfs_dirent but is also buggy - if a sysfs_dirent is removed while there still are pollers, the associaton betwen the kobject and sysfs_dirent breaks and kobject may be freed with the pollers still sleeping on it. This patch moves whole poll implementation into sysfs_open_dirent. Each time a sysfs_open_dirent is created, event number restarts from 1 and pollers sleep on sysfs_open_dirent. As event sequence number is meaningless without any open file and pollers should have open file and thus sysfs_open_dirent, this ephemeral event counting works and is a saner implementation. This patch fixes the dnagling sleepers bug and reduces the sizes of kobject and sysfs_dirent by one pointer. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:12 +09:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: sysfs poll keep the poll rule of regular file. Currently, following test programs don't finished. % ruby -e ' Thread.new { sleep } File.read("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies") ' strace expose the reason. ... open("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies", O_RDONLY|O_LARGEFILE) = 3 ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbf9fa6b8) = -1 ENOTTY (Inappropriate ioctl for device) fstat64(3, {st_mode=S_IFREG|0444, st_size=4096, ...}) = 0 _llseek(3, 0, [0], SEEK_CUR) = 0 select(4, [3], NULL, NULL, NULL) = 1 (in [3]) read(3, "1400000 1300000 1200000 1100000 1"..., 4096) = 62 select(4, [3], NULL, NULL, NULL Because Ruby (the scripting language) VM assume select system-call against regular file don't block. it because SUSv3 says "Regular files shall always poll TRUE for reading and writing". see http://www.opengroup.org/onlinepubs/009695399/functions/poll.html it seems valid assumption. But sysfs_poll() don't keep this rule although sysfs file can read and write always. This patch restore proper poll behavior to sysfs. /sys/block/md*/md/sync_action polling application and another sysfs updating sensitive application still can use POLLERR and POLLPRI. Cc: Neil Brown <neilb@suse.de> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-09 13:53:22 +09:00
sysfs: implement sysfs_dirent active reference and immediate disconnect sysfs: implement sysfs_dirent active reference and immediate disconnect Opening a sysfs node references its associated kobject, so userland can arbitrarily prolong lifetime of a kobject which complicates lifetime rules in drivers. This patch implements active reference and makes the association between kobject and sysfs immediately breakable. Now each sysfs_dirent has two reference counts - s_count and s_active. s_count is a regular reference count which guarantees that the containing sysfs_dirent is accessible. As long as s_count reference is held, all sysfs internal fields in sysfs_dirent are accessible including s_parent and s_name. The newly added s_active is active reference count. This is acquired by invoking sysfs_get_active() and it's the caller's responsibility to ensure sysfs_dirent itself is accessible (should be holding s_count one way or the other). Dereferencing sysfs_dirent to access objects out of sysfs proper requires active reference. This includes access to the associated kobjects, attributes and ops. The active references can be drained and denied by calling sysfs_deactivate(). All active sysfs_dirents must be deactivated after deletion but before the default reference is dropped. This enables immediate disconnect of sysfs nodes. Once a sysfs_dirent is deleted, it won't access any entity external to sysfs proper. Because attr/bin_attr ops access both the node itself and its parent for kobject, they need to hold active references to both. sysfs_get/put_active_two() helpers are provided to help grabbing both references. Parent's is acquired first and released last. Unlike other operations, mmapped area lingers on after mmap() is finished and the module implement implementing it and kobj need to stay referenced till all the mapped pages are gone. This is accomplished by holding one set of active references to the bin_attr and its parent if there have been any mmap during lifetime of an openfile. The references are dropped when the openfile is released. This change makes sysfs lifetime rules independent from both kobject's and module's. It not only fixes several race conditions caused by sysfs not holding onto the proper module when referencing kobject, but also helps fixing and simplifying lifetime management in driver model and drivers by taking sysfs out of the equation. Please read the following message for more info. http://article.gmane.org/gmane.linux.kernel/510293 Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:16 +09:00
sysfs: sysfs poll keep the poll rule of regular file. Currently, following test programs don't finished. % ruby -e ' Thread.new { sleep } File.read("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies") ' strace expose the reason. ... open("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies", O_RDONLY|O_LARGEFILE) = 3 ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbf9fa6b8) = -1 ENOTTY (Inappropriate ioctl for device) fstat64(3, {st_mode=S_IFREG|0444, st_size=4096, ...}) = 0 _llseek(3, 0, [0], SEEK_CUR) = 0 select(4, [3], NULL, NULL, NULL) = 1 (in [3]) read(3, "1400000 1300000 1200000 1100000 1"..., 4096) = 62 select(4, [3], NULL, NULL, NULL Because Ruby (the scripting language) VM assume select system-call against regular file don't block. it because SUSv3 says "Regular files shall always poll TRUE for reading and writing". see http://www.opengroup.org/onlinepubs/009695399/functions/poll.html it seems valid assumption. But sysfs_poll() don't keep this rule although sysfs file can read and write always. This patch restore proper poll behavior to sysfs. /sys/block/md*/md/sync_action polling application and another sysfs updating sensitive application still can use POLLERR and POLLPRI. Cc: Neil Brown <neilb@suse.de> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-09 13:53:22 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16 08:58:04 +10:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16 08:58:04 +10:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16 08:58:04 +10:00
sysfs: Allow sysfs_notify_dirent to be called from interrupt context. sysfs_notify_dirent is a simple atomic operation that can be used to alert user-space that new data can be read from a sysfs attribute. Unfortunately it cannot currently be called from non-process context because of its use of spin_lock which is sometimes taken with interrupts enabled. So change all lockers of sysfs_open_dirent_lock to disable interrupts, thus making sysfs_notify_dirent safe to be called from non-process context (as drivers/md does in md_safemode_timeout). sysfs_get_open_dirent is (documented as being) only called from process context, so it uses spin_lock_irq. Other places use spin_lock_irqsave. The usage for sysfs_notify_dirent in md_safemode_timeout was introduced in 2.6.28, so this patch is suitable for that and more recent kernels. Reported-by: Joel Andres Granados <jgranado@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 16:05:51 -07:00
sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16 08:58:04 +10:00
sysfs: Make dir and name args to sysfs_notify() const Because they can be, and because code like this produces a warning if they're not: struct device_attribute dev_attr; sysfs_notify(&kobj, NULL, dev_attr.attr.name); Signed-off-by: Trent Piepho <tpiepho@freescale.com> CC: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-09-25 16:45:13 -07:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
sysfs: Support sysfs_notify from atomic context with new sysfs_notify_dirent Support sysfs_notify from atomic context with new sysfs_notify_dirent sysfs_notify currently takes sysfs_mutex. This means that it cannot be called in atomic context. sysfs_mutex is sometimes held over a malloc (sysfs_rename_dir) so it can block on low memory. In md I want to be able to notify on a sysfs attribute from atomic context, and I don't want to block on low memory because I could be in the writeout path for freeing memory. So: - export the "sysfs_dirent" structure along with sysfs_get, sysfs_put and sysfs_get_dirent so I can get the sysfs_dirent that I want to notify on and hold it in an md structure. - split sysfs_notify_dirent out of sysfs_notify so the sysfs_dirent can be notified on with no blocking (just a spinlock). Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16 08:58:04 +10:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 01:56:42 -08:00
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] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 17:53:53 +11:00
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
[SCSI] sysfs: make group is_valid return a mode_t We have a problem in scsi_transport_spi in that we need to customise not only the visibility of the attributes, but also their mode. Fix this by making the is_visible() callback return a mode, with 0 indicating is not visible. Also add a sysfs_update_group() API to allow us to change either the visibility or mode of the files at any time on the fly. Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-03-20 20:47:52 -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
[SCSI] sysfs: make group is_valid return a mode_t We have a problem in scsi_transport_spi in that we need to customise not only the visibility of the attributes, but also their mode. Fix this by making the is_visible() callback return a mode, with 0 indicating is not visible. Also add a sysfs_update_group() API to allow us to change either the visibility or mode of the files at any time on the fly. Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-03-20 20:47:52 -05:00
sysfs: restructure add/remove paths and fix inode update The original add/remove code had the following problems. * parent's timestamps are updated on dentry instantiation. this is incorrect with reclaimable files. * updating parent's timestamps isn't synchronized. * parent nlink update assumes the inode is accessible which won't be true once directory dentries are made reclaimable. This patch restructures add/remove paths to resolve the above problems. Add/removal are done in the following steps. 1. sysfs_addrm_start() : acquire locks including sysfs_mutex and other resources. 2-a. sysfs_add_one() : add new sd. linking the new sd into the children list is caller's responsibility. 2-b. sysfs_remove_one() : remove a sd. unlinking the sd from the children list is caller's responsibility. 3. sysfs_addrm_finish() : release all resources and clean up. Steps 2-a and/or 2-b can be repeated multiple times. Parent's inode is looked up during sysfs_addrm_start(). If available (always at the moment), it's pinned and nlink is updated as sd's are added and removed. Timestamps are updated during finish if any sd has been added or removed. If parent's inode is not available during start, sysfs_mutex ensures that parent inode is not created till add/remove is complete. All the complexity is contained inside the helper functions. Especially, dentry/inode handling is properly hidden from the rest of sysfs which now mostly operate on sysfs_dirents. As an added bonus, codes which use these helpers to add and remove sysfs_dirents are now more structured and simpler. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:24 +09:00
sysfs: consolidate sysfs_dirent creation functions Currently there are four functions to create sysfs_dirent - __sysfs_new_dirent(), sysfs_new_dirent(), __sysfs_make_dirent() and sysfs_make_dirent(). Other than sysfs_make_dirent(), no function has two users if calls to implement other functions are excluded. This patch consolidates sysfs_dirent creation functions into the following two. * sysfs_new_dirent() : allocate and initialize * sysfs_attach_dirent() : attach to sysfs_dirent hierarchy and/or associate with dentry This simplifies interface and gives callers more flexibility. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:14 +09:00
sysfs: make sysfs_add_one() automatically check for duplicate entry Make sysfs_add_one() check for duplicate entry and return -EEXIST if such entry exists. This simplifies node addition code a bit. This patch doesn't introduce any noticeable behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 21:38:03 +09:00
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
sysfs: use sysfs_mutex to protect the sysfs_dirent tree As kobj sysfs dentries and inodes are gonna be made reclaimable, i_mutex can't be used to protect sysfs_dirent tree. Use sysfs_mutex globally instead. As the whole tree is protected with sysfs_mutex, there is no reason to keep sysfs_rename_sem. Drop it. While at it, add docbook comments to functions which require sysfs_mutex locking. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:23 +09:00
sysfs: make s_elem an anonymous union Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:11 +09:00
sysfs: Only take active references on attributes. If we exclude directories and symlinks from the set of sysfs dirents where we need active references we are left with sysfs attributes (binary or not). - Tweak sysfs_deactivate to only do something on attributes - Move lockdep initialization into sysfs_file_add_mode to limit it to just attributes. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-11 15:20:00 -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
sysfs: restructure add/remove paths and fix inode update The original add/remove code had the following problems. * parent's timestamps are updated on dentry instantiation. this is incorrect with reclaimable files. * updating parent's timestamps isn't synchronized. * parent nlink update assumes the inode is accessible which won't be true once directory dentries are made reclaimable. This patch restructures add/remove paths to resolve the above problems. Add/removal are done in the following steps. 1. sysfs_addrm_start() : acquire locks including sysfs_mutex and other resources. 2-a. sysfs_add_one() : add new sd. linking the new sd into the children list is caller's responsibility. 2-b. sysfs_remove_one() : remove a sd. unlinking the sd from the children list is caller's responsibility. 3. sysfs_addrm_finish() : release all resources and clean up. Steps 2-a and/or 2-b can be repeated multiple times. Parent's inode is looked up during sysfs_addrm_start(). If available (always at the moment), it's pinned and nlink is updated as sd's are added and removed. Timestamps are updated during finish if any sd has been added or removed. If parent's inode is not available during start, sysfs_mutex ensures that parent inode is not created till add/remove is complete. All the complexity is contained inside the helper functions. Especially, dentry/inode handling is properly hidden from the rest of sysfs which now mostly operate on sysfs_dirents. As an added bonus, codes which use these helpers to add and remove sysfs_dirents are now more structured and simpler. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:24 +09:00
sysfs: make sysfs_add_one() automatically check for duplicate entry Make sysfs_add_one() check for duplicate entry and return -EEXIST if such entry exists. This simplifies node addition code a bit. This patch doesn't introduce any noticeable behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 21:38:03 +09:00
sysfs: consolidate sysfs_dirent creation functions Currently there are four functions to create sysfs_dirent - __sysfs_new_dirent(), sysfs_new_dirent(), __sysfs_make_dirent() and sysfs_make_dirent(). Other than sysfs_make_dirent(), no function has two users if calls to implement other functions are excluded. This patch consolidates sysfs_dirent creation functions into the following two. * sysfs_new_dirent() : allocate and initialize * sysfs_attach_dirent() : attach to sysfs_dirent hierarchy and/or associate with dentry This simplifies interface and gives callers more flexibility. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:14 +09:00
sysfs: make sysfs_add_one() automatically check for duplicate entry Make sysfs_add_one() check for duplicate entry and return -EEXIST if such entry exists. This simplifies node addition code a bit. This patch doesn't introduce any noticeable behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 21:38:03 +09:00
sysfs: cosmetic clean up on node creation failure paths Node addition failure is detected by testing return value of sysfs_addfm_finish() which returns the number of added and removed nodes. As the function is called as the last step of addition right on top of error handling block, the if blocks looked like the following. if (sysfs_addrm_finish(&acxt)) success handling, usually return; /* fall through to error handling */ This is the opposite of usual convention in sysfs and makes the code difficult to understand. This patch inverts the test and makes those blocks look more like others. Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Gabriel C <nix.or.die@googlemail.com> Cc: Miles Lane <miles.lane@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-18 16:38:11 +09:00
sysfs: use sysfs_mutex to protect the sysfs_dirent tree As kobj sysfs dentries and inodes are gonna be made reclaimable, i_mutex can't be used to protect sysfs_dirent tree. Use sysfs_mutex globally instead. As the whole tree is protected with sysfs_mutex, there is no reason to keep sysfs_rename_sem. Drop it. While at it, add docbook comments to functions which require sysfs_mutex locking. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:23 +09:00
sysfs: make sysfs_add_one() automatically check for duplicate entry Make sysfs_add_one() check for duplicate entry and return -EEXIST if such entry exists. This simplifies node addition code a bit. This patch doesn't introduce any noticeable behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 21:38:03 +09:00
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
[SCSI] sysfs: make group is_valid return a mode_t We have a problem in scsi_transport_spi in that we need to customise not only the visibility of the attributes, but also their mode. Fix this by making the is_visible() callback return a mode, with 0 indicating is not visible. Also add a sysfs_update_group() API to allow us to change either the visibility or mode of the files at any time on the fly. Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-03-20 20:47:52 -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
sysfs: trivial: fix sysfs_create_file kerneldoc spelling mistake Spelling error in sysfs_create_file kerneldoc. Signed-off-by: Chris Malley <mail@chrismalley.co.uk> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 03:14:32 +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
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
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
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
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
sysfs: Add sysfs_add/remove_files utility functions Adding/Removing a whole array of attributes is very common. Add a standard utility function to do this with a simple function call, instead of requiring drivers to open code this. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-05 12:48:01 +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
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
[SCSI] sysfs: fix the sysfs_add_file_to_group interfaces I can't see a reason why these shouldn't work on every group. However, they only seem to work on named groups. This patch allows the group functions to work on anonymous groups (those with NULL names). Acked-by: Tejun Heo <htejun@gmail.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-02 18:44:05 -06:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
[SCSI] sysfs: fix the sysfs_add_file_to_group interfaces I can't see a reason why these shouldn't work on every group. However, they only seem to work on named groups. This patch allows the group functions to work on anonymous groups (those with NULL names). Acked-by: Tejun Heo <htejun@gmail.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-02 18:44:05 -06:00
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
[PATCH] sysfs: add sysfs_chmod_file() sysfs: allow changing the permissions for already created attributes Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-18 21:57:32 -07:00
sysfs: sysfs_chmod_file's attr can be const sysfs_chmod_file doesn't change the attribute it operates on, so this attribute can be marked const. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-02 16:54:05 +02:00
[PATCH] sysfs: add sysfs_chmod_file() sysfs: allow changing the permissions for already created attributes Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-18 21:57:32 -07:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
[PATCH] sysfs: fix sysfs_chmod_file o sysfs_chmod_file() must update the new iattr field in sysfs_dirent else the mode change will not be persistent in case of inode evacuation from cache. Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29 12:13:35 -07:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: fix sysfs_chmod_file() such that it updates sd->s_mode too sysfs_chmod_file() looked and updated only inode of the target file. Dentry and inode are reclaimable and the update mode data will go away when the inode is reclaimed. This patch makes sysfs_chmod_file() update sd->s_mode too such that the change is permanent. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:10 +09:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: Simplify sysfs_chmod_file semantics Currently every caller of sysfs_chmod_file happens at either file creation time to set a non-default mode or in response to a specific user requested space change in policy. Making timestamps of when the chmod happens and notification of a file changing mode uninteresting. Remove the unnecessary time stamp and filesystem change notification, and removes the last of the explicit inotify and donitfy support from sysfs. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-07 23:27:02 -08:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: fix sysfs_chmod_file() such that it updates sd->s_mode too sysfs_chmod_file() looked and updated only inode of the target file. Dentry and inode are reclaimable and the update mode data will go away when the inode is reclaimed. This patch makes sysfs_chmod_file() update sd->s_mode too such that the change is permanent. Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-20 16:05:10 +09:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
sysfs: In sysfs_chmod_file lazily propagate the mode change. Now that sysfs_getattr and sysfs_permission refresh the vfs inode there is no need to immediatly push the mode change into the vfs cache. Reducing the amount of work needed and simplifying the locking. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:54 -08:00
sysfs: make directory dentries and inodes reclaimable This patch makes dentries and inodes for sysfs directories reclaimable. * sysfs_notify() is modified to walk sysfs_dirent tree instead of dentry tree. * sysfs_update_file() and sysfs_chmod_file() use sysfs_get_dentry() to grab the victim dentry. * sysfs_rename_dir() and sysfs_move_dir() grab all dentries using sysfs_get_dentry() on startup. * Dentries for all shadowed directories are pinned in memory to serve as lookup start point. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:25 +09:00
[PATCH] sysfs: add sysfs_chmod_file() sysfs: allow changing the permissions for already created attributes Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-18 21:57:32 -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
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -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
sysfs: Add sysfs_add/remove_files utility functions Adding/Removing a whole array of attributes is very common. Add a standard utility function to do this with a simple function call, instead of requiring drivers to open code this. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-05 12:48:01 +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
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
[SCSI] sysfs: fix the sysfs_add_file_to_group interfaces I can't see a reason why these shouldn't work on every group. However, they only seem to work on named groups. This patch allows the group functions to work on anonymous groups (those with NULL names). Acked-by: Tejun Heo <htejun@gmail.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-02 18:44:05 -06:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
[SCSI] sysfs: fix the sysfs_add_file_to_group interfaces I can't see a reason why these shouldn't work on every group. However, they only seem to work on named groups. This patch allows the group functions to work on anonymous groups (those with NULL names). Acked-by: Tejun Heo <htejun@gmail.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-02 18:44:05 -06:00
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
sysfs: Implement sysfs tagged directory support. The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:26 -07:00
sysfs: make kobj point to sysfs_dirent instead of dentry As kobj sysfs dentries and inodes are gonna be made reclaimable, dentry can't be used as naming token for sysfs file/directory, replace kobj->dentry with kobj->sd. The only external interface change is shadow directory handling. All other changes are contained in kobj and sysfs. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:22 +09:00
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -05:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: don't use global workqueue in sysfs_schedule_callback() A sysfs attribute using sysfs_schedule_callback() to commit suicide may end up calling device_unregister(), which will eventually call a driver's ->remove function. Drivers may call flush_scheduled_work() in their shutdown routines, in which case lockdep will complain with something like the following: ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc8-kk #1 --------------------------------------------- events/4/56 is trying to acquire lock: (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 but task is already holding lock: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 other info that might help us debug this: 3 locks held by events/4/56: #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c10d1>] remove_callback+0x21/0x40 stack backtrace: Pid: 56, comm: events/4 Not tainted 2.6.29-rc8-kk #1 Call Trace: [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 [<ffffffff8026f148>] lock_acquire+0x58/0x80 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 [<ffffffffa0144065>] e1000_remove+0x55/0xfe [e1000e] [<ffffffff8033ee30>] ? sysfs_schedule_callback_work+0x0/0x50 [<ffffffff803bfeb2>] pci_device_remove+0x32/0x70 [<ffffffff80441da9>] __device_release_driver+0x59/0x90 [<ffffffff80441edb>] device_release_driver+0x2b/0x40 [<ffffffff804419d6>] bus_remove_device+0xa6/0x120 [<ffffffff8043e46b>] device_del+0x12b/0x190 [<ffffffff8043e4f6>] device_unregister+0x26/0x70 [<ffffffff803ba969>] pci_stop_dev+0x49/0x60 [<ffffffff803baab0>] pci_remove_bus_device+0x40/0xc0 [<ffffffff803c10d9>] remove_callback+0x29/0x40 [<ffffffff8033ee4f>] sysfs_schedule_callback_work+0x1f/0x50 [<ffffffff8025769a>] run_workqueue+0x15a/0x230 [<ffffffff80257648>] ? run_workqueue+0x108/0x230 [<ffffffff8025846f>] worker_thread+0x9f/0x100 [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff802583d0>] ? worker_thread+0x0/0x100 [<ffffffff8025b89d>] kthread+0x4d/0x80 [<ffffffff8020d4ba>] child_rip+0xa/0x20 [<ffffffff8020cebc>] ? restore_args+0x0/0x30 [<ffffffff8025b850>] ? kthread+0x0/0x80 [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 Although we know that the device_unregister path will never acquire a lock that a driver might try to acquire in its ->remove, in general we should never attempt to flush a workqueue from within the same workqueue, and lockdep rightly complains. So as long as sysfs attributes cannot commit suicide directly and we are stuck with this callback mechanism, put the sysfs callbacks on their own workqueue instead of the global one. This has the side benefit that if a suicidal sysfs attribute kicks off a long chain of ->remove callbacks, we no longer induce a long delay on the global queue. This also fixes a missing module_put in the error path introduced by sysfs-only-allow-one-scheduled-removal-callback-per-kobj.patch. We never destroy the workqueue, but I'm not sure that's a problem. Reported-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-25 15:11:36 -06:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
sysfs: don't use global workqueue in sysfs_schedule_callback() A sysfs attribute using sysfs_schedule_callback() to commit suicide may end up calling device_unregister(), which will eventually call a driver's ->remove function. Drivers may call flush_scheduled_work() in their shutdown routines, in which case lockdep will complain with something like the following: ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc8-kk #1 --------------------------------------------- events/4/56 is trying to acquire lock: (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 but task is already holding lock: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 other info that might help us debug this: 3 locks held by events/4/56: #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c10d1>] remove_callback+0x21/0x40 stack backtrace: Pid: 56, comm: events/4 Not tainted 2.6.29-rc8-kk #1 Call Trace: [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 [<ffffffff8026f148>] lock_acquire+0x58/0x80 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 [<ffffffffa0144065>] e1000_remove+0x55/0xfe [e1000e] [<ffffffff8033ee30>] ? sysfs_schedule_callback_work+0x0/0x50 [<ffffffff803bfeb2>] pci_device_remove+0x32/0x70 [<ffffffff80441da9>] __device_release_driver+0x59/0x90 [<ffffffff80441edb>] device_release_driver+0x2b/0x40 [<ffffffff804419d6>] bus_remove_device+0xa6/0x120 [<ffffffff8043e46b>] device_del+0x12b/0x190 [<ffffffff8043e4f6>] device_unregister+0x26/0x70 [<ffffffff803ba969>] pci_stop_dev+0x49/0x60 [<ffffffff803baab0>] pci_remove_bus_device+0x40/0xc0 [<ffffffff803c10d9>] remove_callback+0x29/0x40 [<ffffffff8033ee4f>] sysfs_schedule_callback_work+0x1f/0x50 [<ffffffff8025769a>] run_workqueue+0x15a/0x230 [<ffffffff80257648>] ? run_workqueue+0x108/0x230 [<ffffffff8025846f>] worker_thread+0x9f/0x100 [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff802583d0>] ? worker_thread+0x0/0x100 [<ffffffff8025b89d>] kthread+0x4d/0x80 [<ffffffff8020d4ba>] child_rip+0xa/0x20 [<ffffffff8020cebc>] ? restore_args+0x0/0x30 [<ffffffff8025b850>] ? kthread+0x0/0x80 [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 Although we know that the device_unregister path will never acquire a lock that a driver might try to acquire in its ->remove, in general we should never attempt to flush a workqueue from within the same workqueue, and lockdep rightly complains. So as long as sysfs attributes cannot commit suicide directly and we are stuck with this callback mechanism, put the sysfs callbacks on their own workqueue instead of the global one. This has the side benefit that if a suicidal sysfs attribute kicks off a long chain of ->remove callbacks, we no longer induce a long delay on the global queue. This also fixes a missing module_put in the error path introduced by sysfs-only-allow-one-scheduled-removal-callback-per-kobj.patch. We never destroy the workqueue, but I'm not sure that's a problem. Reported-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-25 15:11:36 -06:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
sysfs: don't use global workqueue in sysfs_schedule_callback() A sysfs attribute using sysfs_schedule_callback() to commit suicide may end up calling device_unregister(), which will eventually call a driver's ->remove function. Drivers may call flush_scheduled_work() in their shutdown routines, in which case lockdep will complain with something like the following: ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc8-kk #1 --------------------------------------------- events/4/56 is trying to acquire lock: (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 but task is already holding lock: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 other info that might help us debug this: 3 locks held by events/4/56: #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c10d1>] remove_callback+0x21/0x40 stack backtrace: Pid: 56, comm: events/4 Not tainted 2.6.29-rc8-kk #1 Call Trace: [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 [<ffffffff8026f148>] lock_acquire+0x58/0x80 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 [<ffffffffa0144065>] e1000_remove+0x55/0xfe [e1000e] [<ffffffff8033ee30>] ? sysfs_schedule_callback_work+0x0/0x50 [<ffffffff803bfeb2>] pci_device_remove+0x32/0x70 [<ffffffff80441da9>] __device_release_driver+0x59/0x90 [<ffffffff80441edb>] device_release_driver+0x2b/0x40 [<ffffffff804419d6>] bus_remove_device+0xa6/0x120 [<ffffffff8043e46b>] device_del+0x12b/0x190 [<ffffffff8043e4f6>] device_unregister+0x26/0x70 [<ffffffff803ba969>] pci_stop_dev+0x49/0x60 [<ffffffff803baab0>] pci_remove_bus_device+0x40/0xc0 [<ffffffff803c10d9>] remove_callback+0x29/0x40 [<ffffffff8033ee4f>] sysfs_schedule_callback_work+0x1f/0x50 [<ffffffff8025769a>] run_workqueue+0x15a/0x230 [<ffffffff80257648>] ? run_workqueue+0x108/0x230 [<ffffffff8025846f>] worker_thread+0x9f/0x100 [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff802583d0>] ? worker_thread+0x0/0x100 [<ffffffff8025b89d>] kthread+0x4d/0x80 [<ffffffff8020d4ba>] child_rip+0xa/0x20 [<ffffffff8020cebc>] ? restore_args+0x0/0x30 [<ffffffff8025b850>] ? kthread+0x0/0x80 [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 Although we know that the device_unregister path will never acquire a lock that a driver might try to acquire in its ->remove, in general we should never attempt to flush a workqueue from within the same workqueue, and lockdep rightly complains. So as long as sysfs attributes cannot commit suicide directly and we are stuck with this callback mechanism, put the sysfs callbacks on their own workqueue instead of the global one. This has the side benefit that if a suicidal sysfs attribute kicks off a long chain of ->remove callbacks, we no longer induce a long delay on the global queue. This also fixes a missing module_put in the error path introduced by sysfs-only-allow-one-scheduled-removal-callback-per-kobj.patch. We never destroy the workqueue, but I'm not sure that's a problem. Reported-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-25 15:11:36 -06:00
sysfs: file.c: use create_singlethread_workqueue() We don't need a kernel thread per CPU for this application. Acked-by: Alex Chiang <achiang@hp.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-05-07 12:36:53 -07:00
sysfs: don't use global workqueue in sysfs_schedule_callback() A sysfs attribute using sysfs_schedule_callback() to commit suicide may end up calling device_unregister(), which will eventually call a driver's ->remove function. Drivers may call flush_scheduled_work() in their shutdown routines, in which case lockdep will complain with something like the following: ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc8-kk #1 --------------------------------------------- events/4/56 is trying to acquire lock: (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 but task is already holding lock: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 other info that might help us debug this: 3 locks held by events/4/56: #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c10d1>] remove_callback+0x21/0x40 stack backtrace: Pid: 56, comm: events/4 Not tainted 2.6.29-rc8-kk #1 Call Trace: [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 [<ffffffff8026f148>] lock_acquire+0x58/0x80 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 [<ffffffffa0144065>] e1000_remove+0x55/0xfe [e1000e] [<ffffffff8033ee30>] ? sysfs_schedule_callback_work+0x0/0x50 [<ffffffff803bfeb2>] pci_device_remove+0x32/0x70 [<ffffffff80441da9>] __device_release_driver+0x59/0x90 [<ffffffff80441edb>] device_release_driver+0x2b/0x40 [<ffffffff804419d6>] bus_remove_device+0xa6/0x120 [<ffffffff8043e46b>] device_del+0x12b/0x190 [<ffffffff8043e4f6>] device_unregister+0x26/0x70 [<ffffffff803ba969>] pci_stop_dev+0x49/0x60 [<ffffffff803baab0>] pci_remove_bus_device+0x40/0xc0 [<ffffffff803c10d9>] remove_callback+0x29/0x40 [<ffffffff8033ee4f>] sysfs_schedule_callback_work+0x1f/0x50 [<ffffffff8025769a>] run_workqueue+0x15a/0x230 [<ffffffff80257648>] ? run_workqueue+0x108/0x230 [<ffffffff8025846f>] worker_thread+0x9f/0x100 [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff802583d0>] ? worker_thread+0x0/0x100 [<ffffffff8025b89d>] kthread+0x4d/0x80 [<ffffffff8020d4ba>] child_rip+0xa/0x20 [<ffffffff8020cebc>] ? restore_args+0x0/0x30 [<ffffffff8025b850>] ? kthread+0x0/0x80 [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 Although we know that the device_unregister path will never acquire a lock that a driver might try to acquire in its ->remove, in general we should never attempt to flush a workqueue from within the same workqueue, and lockdep rightly complains. So as long as sysfs attributes cannot commit suicide directly and we are stuck with this callback mechanism, put the sysfs callbacks on their own workqueue instead of the global one. This has the side benefit that if a suicidal sysfs attribute kicks off a long chain of ->remove callbacks, we no longer induce a long delay on the global queue. This also fixes a missing module_put in the error path introduced by sysfs-only-allow-one-scheduled-removal-callback-per-kobj.patch. We never destroy the workqueue, but I'm not sure that's a problem. Reported-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-25 15:11:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-26 00:12:04 -07:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: only allow one scheduled removal callback per kobj The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-13 12:07:36 -06:00
sysfs: don't use global workqueue in sysfs_schedule_callback() A sysfs attribute using sysfs_schedule_callback() to commit suicide may end up calling device_unregister(), which will eventually call a driver's ->remove function. Drivers may call flush_scheduled_work() in their shutdown routines, in which case lockdep will complain with something like the following: ============================================= [ INFO: possible recursive locking detected ] 2.6.29-rc8-kk #1 --------------------------------------------- events/4/56 is trying to acquire lock: (events){--..}, at: [<ffffffff80257fc0>] flush_workqueue+0x0/0xa0 but task is already holding lock: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 other info that might help us debug this: 3 locks held by events/4/56: #0: (events){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #1: (&ss->work){--..}, at: [<ffffffff80257648>] run_workqueue+0x108/0x230 #2: (pci_remove_rescan_mutex){--..}, at: [<ffffffff803c10d1>] remove_callback+0x21/0x40 stack backtrace: Pid: 56, comm: events/4 Not tainted 2.6.29-rc8-kk #1 Call Trace: [<ffffffff8026dfcd>] validate_chain+0xb7d/0x1260 [<ffffffff8026eade>] __lock_acquire+0x42e/0xa40 [<ffffffff8026f148>] lock_acquire+0x58/0x80 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff8025800d>] flush_workqueue+0x4d/0xa0 [<ffffffff80257fc0>] ? flush_workqueue+0x0/0xa0 [<ffffffff80258070>] flush_scheduled_work+0x10/0x20 [<ffffffffa0144065>] e1000_remove+0x55/0xfe [e1000e] [<ffffffff8033ee30>] ? sysfs_schedule_callback_work+0x0/0x50 [<ffffffff803bfeb2>] pci_device_remove+0x32/0x70 [<ffffffff80441da9>] __device_release_driver+0x59/0x90 [<ffffffff80441edb>] device_release_driver+0x2b/0x40 [<ffffffff804419d6>] bus_remove_device+0xa6/0x120 [<ffffffff8043e46b>] device_del+0x12b/0x190 [<ffffffff8043e4f6>] device_unregister+0x26/0x70 [<ffffffff803ba969>] pci_stop_dev+0x49/0x60 [<ffffffff803baab0>] pci_remove_bus_device+0x40/0xc0 [<ffffffff803c10d9>] remove_callback+0x29/0x40 [<ffffffff8033ee4f>] sysfs_schedule_callback_work+0x1f/0x50 [<ffffffff8025769a>] run_workqueue+0x15a/0x230 [<ffffffff80257648>] ? run_workqueue+0x108/0x230 [<ffffffff8025846f>] worker_thread+0x9f/0x100 [<ffffffff8025bce0>] ? autoremove_wake_function+0x0/0x40 [<ffffffff802583d0>] ? worker_thread+0x0/0x100 [<ffffffff8025b89d>] kthread+0x4d/0x80 [<ffffffff8020d4ba>] child_rip+0xa/0x20 [<ffffffff8020cebc>] ? restore_args+0x0/0x30 [<ffffffff8025b850>] ? kthread+0x0/0x80 [<ffffffff8020d4b0>] ? child_rip+0x0/0x20 Although we know that the device_unregister path will never acquire a lock that a driver might try to acquire in its ->remove, in general we should never attempt to flush a workqueue from within the same workqueue, and lockdep rightly complains. So as long as sysfs attributes cannot commit suicide directly and we are stuck with this callback mechanism, put the sysfs callbacks on their own workqueue instead of the global one. This has the side benefit that if a suicidal sysfs attribute kicks off a long chain of ->remove callbacks, we no longer induce a long delay on the global queue. This also fixes a missing module_put in the error path introduced by sysfs-only-allow-one-scheduled-removal-callback-per-kobj.patch. We never destroy the workqueue, but I'm not sure that's a problem. Reported-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-25 15:11:36 -06:00
[PATCH] sysfs and driver core: add callback helper, used by SCSI and S390 This patch (as868) adds a helper routine for device drivers that need to set up a callback to perform some action in a different process's context. This is intended for use by attribute methods that want to unregister themselves or their parent device. Attribute method calls are mutually exclusive with unregistration, so such actions cannot be taken directly. Two attribute methods are converted to use the new helper routine: one for SCSI device deletion and one for System/390 ccwgroup devices. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Hugh Dickins <hugh@veritas.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Oliver Neukum <oneukum@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-15 15:50:34 -04:00
sysfs: allow attributes to be added to groups This patch (as860) adds two new sysfs routines: sysfs_add_file_to_group() and sysfs_remove_file_from_group(). A later patch adds code that uses the new routines. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-20 15:02:44 -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
sysfs: Add sysfs_add/remove_files utility functions Adding/Removing a whole array of attributes is very common. Add a standard utility function to do this with a simple function call, instead of requiring drivers to open code this. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-05 12:48:01 +01:00