linux/fs
Tejun Heo fb6896da37 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>
2007-07-11 16:09:09 -07:00
..
9p Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
adfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
affs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
afs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
autofs Replace pid_t in autofs with struct pid reference 2007-05-11 08:29:36 -07:00
autofs4 Fix some coding-style errors in autofs 2007-05-11 08:29:36 -07:00
befs Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
bfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
cifs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
coda sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
configfs Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
cramfs mm: make read_cache_page synchronous 2007-05-07 12:12:51 -07:00
debugfs debugfs: add rename for debugfs files 2007-07-11 16:09:00 -07:00
devpts devpts: add fsnotify create event 2007-05-08 11:14:59 -07:00
dlm [DLM] dump more lock values 2007-07-09 08:24:13 +01:00
ecryptfs sysfs: kill unnecessary attribute->owner 2007-07-11 16:09:06 -07:00
efs Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
exportfs header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
ext2 xip sendfile removal 2007-07-10 08:04:15 +02:00
ext3 sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
ext4 sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
fat sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
freevxfs freevxfs: possible null pointer dereference fix 2007-05-08 11:14:59 -07:00
fuse sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
gfs2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw 2007-07-10 13:56:13 -07:00
hfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
hfsplus sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
hostfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
hpfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
hppfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
hugetlbfs shm: fix the filename of hugetlb sysv shared memory 2007-06-16 13:16:16 -07:00
isofs Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
jbd fix file specification in comments 2007-05-09 08:58:16 +02:00
jbd2 fix file specification in comments 2007-05-09 08:58:16 +02:00
jffs2 sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
jfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
lockd NLM: Fix sparse warnings 2007-05-14 19:33:46 -04:00
minix sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
msdos [PATCH] mark struct inode_operations const 2 2007-02-12 09:48:46 -08:00
ncpfs Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
nfs sendfile: convert nfs to using splice_read() 2007-07-10 08:04:14 +02:00
nfs_common
nfsd pipe: change the ->pin() operation to ->confirm() 2007-07-10 08:04:15 +02:00
nls
ntfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
ocfs2 sysfs: kill unnecessary attribute->owner 2007-07-11 16:09:06 -07:00
openpromfs Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
partitions sysfs: kill unnecessary attribute->owner 2007-07-11 16:09:06 -07:00
proc sched: scheduler debugging, core 2007-07-09 18:52:00 +02:00
qnx4 sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
ramfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
reiserfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
romfs Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
smbfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
sysfs sysfs: restructure add/remove paths and fix inode update 2007-07-11 16:09:09 -07:00
sysv sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
udf sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
ufs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
vfat [PATCH] mark struct inode_operations const 3 2007-02-12 09:48:46 -08:00
xfs sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
aio.c signal/timer/event: KAIO eventfd support example 2007-05-11 08:29:37 -07:00
anon_inodes.c signal/timer/event fds: anonymous inode source 2007-05-11 08:29:36 -07:00
attr.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
bad_inode.c sendfile: remove bad_sendfile() from bad_file_ops 2007-07-10 08:04:15 +02:00
binfmt_aout.c
binfmt_elf_fdpic.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
binfmt_elf.c Fix elf_core_dump() when writing arch specific notes (spu coredumps) 2007-07-06 10:23:43 -07:00
binfmt_em86.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
binfmt_flat.c nommu: report correct errno in message 2007-06-08 17:23:32 -07:00
binfmt_misc.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
binfmt_script.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
binfmt_som.c
bio.c unexport bio_{,un}map_user 2007-07-10 08:03:34 +02:00
block_dev.c sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
buffer.c Fix "fs: convert core functions to zero_user_page" 2007-05-21 09:15:32 -07:00
char_dev.c [PATCH] remove protection of LANANA-reserved majors 2007-04-04 21:12:47 -07:00
compat_ioctl.c fix compat console unimap regression 2007-05-25 17:37:46 -07:00
compat.c optimize compat_core_sys_select() by a using stack space for small fd sets 2007-05-23 20:14:12 -07:00
dcache.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
dcookies.c
direct-io.c dio: remove bogus refcounting BUG_ON 2007-07-03 18:23:23 -07:00
dnotify.c
dquot.c circular locking dependency found in QUOTA OFF 2007-05-17 05:23:05 -07:00
drop_caches.c [PATCH] remove invalidate_inode_pages() 2007-02-11 10:51:31 -08:00
eventfd.c eventfd use waitqueue lock ... 2007-05-18 13:09:34 -07:00
eventpoll.c epoll: move kfree inside ep_free 2007-05-15 08:54:00 -07:00
exec.c uselib: add missing MNT_NOEXEC check 2007-05-23 20:14:13 -07:00
fcntl.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
fifo.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
file_table.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
file.c [PATCH] fdtable: Provide free_fdtable() wrapper 2006-12-22 08:55:50 -08:00
filesystems.c add filesystem subtype support 2007-05-08 11:15:01 -07:00
fs-writeback.c Write back inode data pages even when the inode itself is locked 2007-01-26 12:53:20 -08:00
generic_acl.c
inode.c Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
inotify_user.c [PATCH] inotify: read return val fix 2007-02-12 09:48:28 -08:00
inotify.c Introduce a handy list_first_entry macro 2007-05-08 11:15:11 -07:00
internal.h cleanup compat ioctl handling 2007-05-08 11:15:09 -07:00
ioctl.c vanishing ioctl handler debugging 2007-06-04 13:25:10 -07:00
ioprio.c [PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task 2007-02-12 09:48:32 -08:00
Kconfig Remove obsolete fat_cvf help text 2007-05-09 08:58:15 +02:00
Kconfig.binfmt fs: Kill sh dependency for binfmt_flat. 2007-05-21 14:34:00 +09:00
libfs.c fs/libfs.c: >80 columns line break fix 2007-05-09 06:44:57 +02:00
locks.c Remove SLAB_CTOR_CONSTRUCTOR 2007-05-17 05:23:04 -07:00
Makefile signal/timer/event: eventfd core 2007-05-11 08:29:36 -07:00
mbcache.c
mpage.c consolidate generic_writepages and mpage_writepages 2007-05-11 08:29:35 -07:00
namei.c [PATCH] complete message queue auditing 2007-05-11 05:38:26 -04:00
namespace.c check privileges before setting mount propagation 2007-05-08 11:15:12 -07:00
nfsctl.c
no-block.c
open.c Remove suid/sgid bits on [f]truncate() 2007-05-08 20:10:00 -07:00
pipe.c pipe: add documentation and comments 2007-07-10 08:04:16 +02:00
pnode.c Introduce a handy list_first_entry macro 2007-05-08 11:15:11 -07:00
pnode.h
posix_acl.c
quota_v1.c
quota_v2.c
quota.c circular locking dependency found in QUOTA OFF 2007-05-17 05:23:05 -07:00
read_write.c Remove remnants of sendfile() 2007-07-10 08:04:15 +02:00
read_write.h
readdir.c ROUND_UP macro cleanup in fs/(select|compat|readdir).c 2007-05-08 11:15:09 -07:00
select.c Style fix in fs/select.c 2007-05-09 07:10:02 +02:00
seq_file.c Make common helpers for seq_files that work with list_heads 2007-07-10 17:51:13 -07:00
signalfd.c avoid spurious POLLIN returns in signalfd 2007-06-28 11:34:54 -07:00
splice.c pipe: add documentation and comments 2007-07-10 08:04:16 +02:00
stack.c [PATCH] fs/stack.c: Copy i_nlink after all other attributes are copied 2007-02-19 14:21:50 -08:00
stat.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
super.c add filesystem subtype support 2007-05-08 11:15:01 -07:00
sync.c Introduce fixed sys_sync_file_range2() syscall, implement on PowerPC and ARM 2007-06-28 11:38:30 -07:00
timerfd.c timerfd use waitqueue lock ... 2007-05-18 13:09:34 -07:00
utimes.c Fix permission checking for the new utimensat() system call 2007-07-08 12:02:55 -07:00
xattr_acl.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
xattr.c [PATCH] audit inode for all xattr syscalls 2007-05-11 05:38:26 -04:00