linux/fs/sysfs
Tejun Heo 0cae60f914 sysfs: rename sysfs_assoc_lock and explain what it's about
sysfs_assoc_lock is an odd piece of locking.  In general, whoever owns
a kobject is responsible for synchronizing sysfs operations and sysfs
proper assumes that, for example, removal won't race with any other
operation; however, this doesn't work for symlinking because an entity
performing symlink doesn't usually own the target kobject and thus has
no control over its removal.

sysfs_assoc_lock synchronizes symlink operations against kobj->sd
disassociation so that symlink code doesn't end up dereferencing
already freed sysfs_dirent by racing with removal of the target
kobject.

This is quite obscure and the generic name of the lock and lack of
comments make it difficult to understand its role.  Let's rename it to
sysfs_symlink_target_lock and add comments explaining what's going on.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-01 12:13:37 -07:00
..
dir.c sysfs: rename sysfs_assoc_lock and explain what it's about 2013-11-01 12:13:37 -07:00
file.c sysfs: use generic_file_llseek() for sysfs_file_operations 2013-11-01 12:13:37 -07:00
group.c sysfs: introduce [__]sysfs_remove() 2013-10-03 16:38:52 -07:00
inode.c sysfs: move sysfs_hash_and_remove() to fs/sysfs/dir.c 2013-10-29 15:12:07 -07:00
Kconfig kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
Makefile sysfs: merge regular and bin file handling 2013-10-05 17:27:40 -07:00
mount.c sysfs: drop kobj_ns_type handling 2013-09-26 15:30:22 -07:00
symlink.c sysfs: rename sysfs_assoc_lock and explain what it's about 2013-11-01 12:13:37 -07:00
sysfs.h sysfs: rename sysfs_assoc_lock and explain what it's about 2013-11-01 12:13:37 -07:00