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linux/fs/sysfs/sysfs.h

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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
sysfs: Add lockdep annotations for the sysfs active reference Holding locks over device_del -> kobject_del -> sysfs_deactivate can cause deadlocks if those same locks are grabbed in sysfs show or store methods. The I model s_active count + completion as a sleeping read/write lock. I describe to lockdep sysfs_get_active as a read_trylock, sysfs_put_active as a read_unlock, and sysfs_deactivate as a write_lock and write_unlock pair. This seems to capture the essence for purposes of finding deadlocks, and in my testing gives finds real issues and ignores non-issues. This brings us back to holding locks over kobject_del is a problem that ideally we should find a way of addressing, but at least lockdep can tell us about the problems instead of requiring developers to debug rare strange system deadlocks, that happen when sysfs files are removed while being written to. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 13:37:12 -08:00
sysfs: Add labeling support for sysfs This patch adds a setxattr handler to the file, directory, and symlink inode_operations structures for sysfs. The patch uses hooks introduced in the previous patch to handle the getting and setting of security information for the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the sysfs_dirent structure has been replaced by a structure which contains the iattr, secdata and secdata length to allow the changes to persist in the event that the inode representing the sysfs_dirent is evicted. Because sysfs only stores this information when a change is made all the optional data is moved into one dynamically allocated field. This patch addresses an issue where SELinux was denying virtd access to the PCI configuration entries in sysfs. The lack of setxattr handlers for sysfs required that a single label be assigned to all entries in sysfs. Granting virtd access to every entry in sysfs is not an acceptable solution so fine grained labeling of sysfs is required such that individual entries can be labeled appropriately. [sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.] Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-09 14:25:37 -04:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir Children list head is only meaninful for directory nodes. Move it into s_dir. This doesn't save any space currently but it will with further changes. 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 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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: 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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: don't block indefinitely for unmapped files. Modify sysfs bin files so that we can remove the bin file while they are still mapped. When the kobject is removed we unmap the bin file and arrange for future accesses to the mapping to receive SIGBUS. Implementing this prevents a nasty DOS when pci devices are hot plugged and unplugged. Where if any of their resources were mmaped the kernel could not free up their pci resources or release their pci data structures. [akpm@linux-foundation.org: remove unused var] Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-04 11:57:20 -08:00
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: Add labeling support for sysfs This patch adds a setxattr handler to the file, directory, and symlink inode_operations structures for sysfs. The patch uses hooks introduced in the previous patch to handle the getting and setting of security information for the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the sysfs_dirent structure has been replaced by a structure which contains the iattr, secdata and secdata length to allow the changes to persist in the event that the inode representing the sysfs_dirent is evicted. Because sysfs only stores this information when a change is made all the optional data is moved into one dynamically allocated field. This patch addresses an issue where SELinux was denying virtd access to the PCI configuration entries in sysfs. The lack of setxattr handlers for sysfs required that a single label be assigned to all entries in sysfs. Granting virtd access to every entry in sysfs is not an acceptable solution so fine grained labeling of sysfs is required such that individual entries can be labeled appropriately. [sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.] Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-09 14:25:37 -04:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: move struct sysfs_dirent to private header struct sysfs_dirent is private to the fs/sysfs/ subtree. It is not even referenced as an opaque structure outside of that subtree. The following patch moves the declaration from include/linux/sysfs.h to fs/sysfs/sysfs.h, making it clearer that nothing else in the kernel dereferences it. I have been running this patch for years. Please integrate and forward upstream if there are no objections. From: "Adam J. Richter" <adam@yggdrasil.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 21:35:25 +08:00
sysfs: slim down sysfs_dirent->s_active Make sysfs_dirent->s_active an atomic_t instead of rwsem. This reduces the size of sysfs_dirent from 136 to 104 on 64bit and from 76 to 60 on 32bit with lock debugging turned off. With lock debugging turned on the reduction is much larger. s_active starts at zero and each active reference increments s_active. Putting a reference decrements s_active. Deactivation subtracts SD_DEACTIVATED_BIAS which is currently INT_MIN and assumed to be small enough to make s_active negative. If s_active is negative, sysfs_get() no longer grants new references. Deactivation succeeds immediately if there is no active user; otherwise, it waits using a completion for the last put. Due to the removal of lockdep tricks, this change makes things less trickier in release_sysfs_dirent(). As all the complexity is contained in three s_active functions, I think it's more readable this way. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 03:45:18 +09:00
sysfs: Add lockdep annotations for the sysfs active reference Holding locks over device_del -> kobject_del -> sysfs_deactivate can cause deadlocks if those same locks are grabbed in sysfs show or store methods. The I model s_active count + completion as a sleeping read/write lock. I describe to lockdep sysfs_get_active as a read_trylock, sysfs_put_active as a read_unlock, and sysfs_deactivate as a write_lock and write_unlock pair. This seems to capture the essence for purposes of finding deadlocks, and in my testing gives finds real issues and ignores non-issues. This brings us back to holding locks over kobject_del is a problem that ideally we should find a way of addressing, but at least lockdep can tell us about the problems instead of requiring developers to debug rare strange system deadlocks, that happen when sysfs files are removed while being written to. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 13:37:12 -08:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
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: Comment sysfs directory tagging logic Add some in-line comments to explain the new infrastructure, which was introduced to support sysfs directory tagging with namespaces. I think an overall description someplace might be good too, but it didn't really seem to fit into Documentation/filesystems/sysfs.txt, which appears more geared toward users, rather than maintainers, of sysfs. (Tejun, please let me know if I can make anything clearer or failed altogether to comment something that should be commented.) Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-03 16:23:15 -05:00
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
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: rename sysfs_dirent->s_type to s_flags and make room for flags Rename sysfs_dirent->s_type to s_flags, pack type into lower eight bits and reserve the rest for flags. sysfs_type() can used to access the type. All existing sd->s_type accesses are converted to use sysfs_type(). While at it, type test is changed to equality test instead of bit-and test where appropriate. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-14 04:27:21 +09:00
sysfs: Pack sysfs_dirent more tightly. Placing the 16bit s_mode between a pointer and a long doesn't pack well especailly on 64bit where we wast 48 bits. So move s_mode and declare it as a unsigned short. This is the sysfs backing store after all we don't need fields extra large just in case someday we want userspace to be able to use a larger value. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-12 19:22:24 -08:00
sysfs: store sysfs inode nrs in s_ino to avoid readdir oopses Backport of ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc1/2.6.22-rc1-mm1/broken-out/gregkh-driver-sysfs-allocate-inode-number-using-ida.patch For regular files in sysfs, sysfs_readdir wants to traverse sysfs_dirent->s_dentry->d_inode->i_ino to get to the inode number. But, the dentry can be reclaimed under memory pressure, and there is no synchronization with readdir. This patch follows Tejun's scheme of allocating and storing an inode number in the new s_ino member of a sysfs_dirent, when dirents are created, and retrieving it from there for readdir, so that the pointer chain doesn't have to be traversed. Tejun's upstream patch uses a new-ish "ida" allocator which brings along some extra complexity; this -stable patch has a brain-dead incrementing counter which does not guarantee uniqueness, but because sysfs doesn't hash inodes as iunique expects, uniqueness wasn't guaranteed today anyway. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-11 14:02:45 +09:00
sysfs: Add labeling support for sysfs This patch adds a setxattr handler to the file, directory, and symlink inode_operations structures for sysfs. The patch uses hooks introduced in the previous patch to handle the getting and setting of security information for the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the sysfs_dirent structure has been replaced by a structure which contains the iattr, secdata and secdata length to allow the changes to persist in the event that the inode representing the sysfs_dirent is evicted. Because sysfs only stores this information when a change is made all the optional data is moved into one dynamically allocated field. This patch addresses an issue where SELinux was denying virtd access to the PCI configuration entries in sysfs. The lack of setxattr handlers for sysfs required that a single label be assigned to all entries in sysfs. Granting virtd access to every entry in sysfs is not an acceptable solution so fine grained labeling of sysfs is required such that individual entries can be labeled appropriately. [sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.] Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-09 14:25:37 -04:00
sysfs: move struct sysfs_dirent to private header struct sysfs_dirent is private to the fs/sysfs/ subtree. It is not even referenced as an opaque structure outside of that subtree. The following patch moves the declaration from include/linux/sysfs.h to fs/sysfs/sysfs.h, making it clearer that nothing else in the kernel dereferences it. I have been running this patch for years. Please integrate and forward upstream if there are no objections. From: "Adam J. Richter" <adam@yggdrasil.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 21:35:25 +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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: make sysfs_root a regular directory dirent sysfs_root is different from a regular directory dirent in that it's of type SYSFS_ROOT and doesn't have a name. These differences aren't used by anybody and only adds to complexity. Make sysfs_root a regular directory dirent. 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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Comment sysfs directory tagging logic Add some in-line comments to explain the new infrastructure, which was introduced to support sysfs directory tagging with namespaces. I think an overall description someplace might be good too, but it didn't really seem to fit into Documentation/filesystems/sysfs.txt, which appears more geared toward users, rather than maintainers, of sysfs. (Tejun, please let me know if I can make anything clearer or failed altogether to comment something that should be commented.) Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-03 16:23:15 -05:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Comment sysfs directory tagging logic Add some in-line comments to explain the new infrastructure, which was introduced to support sysfs directory tagging with namespaces. I think an overall description someplace might be good too, but it didn't really seem to fit into Documentation/filesystems/sysfs.txt, which appears more geared toward users, rather than maintainers, of sysfs. (Tejun, please let me know if I can make anything clearer or failed altogether to comment something that should be commented.) Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-03 16:23:15 -05:00
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: Add lockdep annotations for the sysfs active reference Holding locks over device_del -> kobject_del -> sysfs_deactivate can cause deadlocks if those same locks are grabbed in sysfs show or store methods. The I model s_active count + completion as a sleeping read/write lock. I describe to lockdep sysfs_get_active as a read_trylock, sysfs_put_active as a read_unlock, and sysfs_deactivate as a write_lock and write_unlock pair. This seems to capture the essence for purposes of finding deadlocks, and in my testing gives finds real issues and ignores non-issues. This brings us back to holding locks over kobject_del is a problem that ideally we should find a way of addressing, but at least lockdep can tell us about the problems instead of requiring developers to debug rare strange system deadlocks, that happen when sysfs files are removed while being written to. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 13:37:12 -08:00
sysfs: Use one lockdep class per sysfs attribute. Acknowledge that the logical sysfs rwsem has one instance per sysfs attribute with different locking depencencies for different attributes. There is a sysfs idiom where writing to one sysfs file causes the addition or removal of other sysfs files. Lumping all of the sysfs attributes together in one lock class causes lockdep to generate lots of false positives. This introduces the requirement that non-static sysfs attributes need to be initialized with sysfs_attr_init or sysfs_bin_attr_init. Strictly speaking this requirement only exists when lockdep is enabled, and when lockdep is enabled we get a bit fat warning if this requirement is not met. 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 15:21:53 -08:00
sysfs: Add lockdep annotations for the sysfs active reference Holding locks over device_del -> kobject_del -> sysfs_deactivate can cause deadlocks if those same locks are grabbed in sysfs show or store methods. The I model s_active count + completion as a sleeping read/write lock. I describe to lockdep sysfs_get_active as a read_trylock, sysfs_put_active as a read_unlock, and sysfs_deactivate as a write_lock and write_unlock pair. This seems to capture the essence for purposes of finding deadlocks, and in my testing gives finds real issues and ignores non-issues. This brings us back to holding locks over kobject_del is a problem that ideally we should find a way of addressing, but at least lockdep can tell us about the problems instead of requiring developers to debug rare strange system deadlocks, that happen when sysfs files are removed while being written to. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 13:37:12 -08:00
sysfs: Use one lockdep class per sysfs attribute. Acknowledge that the logical sysfs rwsem has one instance per sysfs attribute with different locking depencencies for different attributes. There is a sysfs idiom where writing to one sysfs file causes the addition or removal of other sysfs files. Lumping all of the sysfs attributes together in one lock class causes lockdep to generate lots of false positives. This introduces the requirement that non-static sysfs attributes need to be initialized with sysfs_attr_init or sysfs_bin_attr_init. Strictly speaking this requirement only exists when lockdep is enabled, and when lockdep is enabled we get a bit fat warning if this requirement is not met. 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 15:21:53 -08:00
sysfs: Add lockdep annotations for the sysfs active reference Holding locks over device_del -> kobject_del -> sysfs_deactivate can cause deadlocks if those same locks are grabbed in sysfs show or store methods. The I model s_active count + completion as a sleeping read/write lock. I describe to lockdep sysfs_get_active as a read_trylock, sysfs_put_active as a read_unlock, and sysfs_deactivate as a write_lock and write_unlock pair. This seems to capture the essence for purposes of finding deadlocks, and in my testing gives finds real issues and ignores non-issues. This brings us back to holding locks over kobject_del is a problem that ideally we should find a way of addressing, but at least lockdep can tell us about the problems instead of requiring developers to debug rare strange system deadlocks, that happen when sysfs files are removed while being written to. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-02 13:37:12 -08:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Comment sysfs directory tagging logic Add some in-line comments to explain the new infrastructure, which was introduced to support sysfs directory tagging with namespaces. I think an overall description someplace might be good too, but it didn't really seem to fit into Documentation/filesystems/sysfs.txt, which appears more geared toward users, rather than maintainers, of sysfs. (Tejun, please let me know if I can make anything clearer or failed altogether to comment something that should be commented.) Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-03 16:23:15 -05:00
sysfs: Basic support for multiple super blocks Add all of the necessary bioler plate to support multiple superblocks in sysfs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:24 -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
sysfs: Basic support for multiple super blocks Add all of the necessary bioler plate to support multiple superblocks in sysfs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30 11:31:24 -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
[PATCH] slab: remove kmem_cache_t Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06 20:33:20 -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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 01:56:42 -08:00
[PATCH] mark struct inode_operations const 3 Many struct inode_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. 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>
2007-02-12 00:55:40 -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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
driver core: Suppress sysfs warnings for device_rename(). driver core: Suppress sysfs warnings for device_rename(). Renaming network devices to an already existing name is not something we want sysfs to print a scary warning for, since the callers can deal with this correctly. So let's introduce sysfs_create_link_nowarn() which gets rid of the common warning. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-06-10 11:09:08 +02:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Factor out sysfs_rename from sysfs_rename_dir and sysfs_move_dir These two functions do 90% of the same work and it doesn't significantly obfuscate the function to allow both the parent dir and the name to change at the same time. So merge them together to simplify maintenance, and increase testing. 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 16:08:57 -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: Factor out sysfs_rename from sysfs_rename_dir and sysfs_move_dir These two functions do 90% of the same work and it doesn't significantly obfuscate the function to allow both the parent dir and the name to change at the same time. So merge them together to simplify maintenance, and increase testing. 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 16:08:57 -08:00
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
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: 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
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: 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
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: 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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Pass super_block to sysfs_get_inode Currently sysfs_get_inode magically returns an inode on sysfs_sb. Make the super_block parameter explicit and the code becomes clearer. 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>
2010-02-12 19:22:27 -08:00
switch sysfs to ->evict_inode() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-06-04 22:21:54 -04:00
sysfs: Fix locking and factor out sysfs_sd_setattr Cleanly separate the work that is specific to setting the attributes of a sysfs_dirent from what is needed to update the attributes of a vfs inode. Additionally grab the sysfs_mutex to keep any nasties from surprising us when updating the sysfs_dirent. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-11-20 16:08:50 -08:00
fs: provide rcu-walk aware permission i_ops Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:49:58 +11:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: Implement sysfs_getattr & sysfs_permission With the implementation of sysfs_getattr and sysfs_permission sysfs becomes able to lazily propogate inode attribute changes from the sysfs_dirents to the vfs inodes. This paves the way for deleting significant chunks of now unnecessary code. While doing this we did not reference sysfs_setattr from sysfs_symlink_inode_operations so I added along with sysfs_getattr and sysfs_permission. 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 16:08:53 -08:00
sysfs: Add labeling support for sysfs This patch adds a setxattr handler to the file, directory, and symlink inode_operations structures for sysfs. The patch uses hooks introduced in the previous patch to handle the getting and setting of security information for the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the sysfs_dirent structure has been replaced by a structure which contains the iattr, secdata and secdata length to allow the changes to persist in the event that the inode representing the sysfs_dirent is evicted. Because sysfs only stores this information when a change is made all the optional data is moved into one dynamically allocated field. This patch addresses an issue where SELinux was denying virtd access to the PCI configuration entries in sysfs. The lack of setxattr handlers for sysfs required that a single label be assigned to all entries in sysfs. Granting virtd access to every entry in sysfs is not an acceptable solution so fine grained labeling of sysfs is required such that individual entries can be labeled appropriately. [sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.] Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-09 14:25:37 -04:00
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
mm: bdi init hooks provide BDI constructor/destructor hooks [akpm@linux-foundation.org: compile fix] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 23:25:46 -07:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
[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: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00
sysfs: don't block indefinitely for unmapped files. Modify sysfs bin files so that we can remove the bin file while they are still mapped. When the kobject is removed we unmap the bin file and arrange for future accesses to the mapping to receive SIGBUS. Implementing this prevents a nasty DOS when pci devices are hot plugged and unplugged. Where if any of their resources were mmaped the kernel could not free up their pci resources or release their pci data structures. [akpm@linux-foundation.org: remove unused var] Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-03-04 11:57:20 -08:00
sysfs: clean up header files sysfs is about to go through major overhaul making this a pretty good opportunity to clean up (out-of-tree changes and pending patches will need regeneration anyway). Clean up headers. * Kill space between * and symbolname. * Move SYSFS_* type constants and flags into fs/sysfs/sysfs.h. They're internal to sysfs. * Reformat function prototypes and add argument symbol names. * Make dummy function definition order match that of function prototypes. * Add some comments. * Reorganize fs/sysfs/sysfs.h according to which file the declared variable or feature lives in. This patch does not introduce any 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>
2007-09-20 16:05:10 +09:00