Commit Graph

12 Commits

Author SHA1 Message Date
Alexey Dobriyan
0d54b217a2 const: make struct super_block::s_qcop const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan
61e225dc34 const: make struct super_block::dq_op const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Jan Kara
dee865656f quota: Silence lockdep on quota_on
Commit d01730d74d didn't completely fix
the problem since we still take dqio_mutex and i_mutex in the wrong
order. Move taking of i_mutex further down (luckily it's needed only
for updating inode flags) below where dqio_mutex is taken.

Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-07-30 17:31:23 +02:00
Jiaying Zhang
d01730d74d quota: Fix possible deadlock during parallel quotaon and quotaoff
The following test script triggers a deadlock on ext2 filesystem:
while true; do quotaon /dev/hda >&/dev/null; usleep $RANDOM; done &
while true; do quotaoff /dev/hda >&/dev/null; usleep $RANDOM; done &

I found there is a potential deadlock between quotaon and quotaoff (or
quotasync). Basically, all of quotactl operations need to be protected by
dqonoff_mutex. vfs_quota_off and vfs_quota_sync also call sb->s_op->quota_write
that needs to grab the i_mutex of the quota file.  But in vfs_quota_on_inode
(called from quotaon operation), the current code tries to grab  the i_mutex of
the quota file first before getting quonoff_mutex.

Reverse the order in which we take locks in vfs_quota_on_inode().

Jan Kara: Changed changelog to be more readable, made lockdep happy with
  I_MUTEX_QUOTA.

Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2009-07-07 18:15:21 +02:00
Wu Fengguang
b6fac63cc1 vfs: skip I_CLEAR state inodes
clear_inode() will switch inode state from I_FREEING to I_CLEAR, and do so
_outside_ of inode_lock.  So any I_FREEING testing is incomplete without a
coupled testing of I_CLEAR.

So add I_CLEAR tests to drop_pagecache_sb(), generic_sync_sb_inodes() and
add_dquot_ref().

Masayoshi MIZUMA discovered the bug in drop_pagecache_sb() and Jan Kara
reminds fixing the other two cases.

Masayoshi MIZUMA has a nice panic flow:

=====================================================================
            [process A]               |        [process B]
 |                                    |
 |    prune_icache()                  | drop_pagecache()
 |      spin_lock(&inode_lock)        |   drop_pagecache_sb()
 |      inode->i_state |= I_FREEING;  |       |
 |      spin_unlock(&inode_lock)      |       V
 |          |                         |     spin_lock(&inode_lock)
 |          V                         |         |
 |      dispose_list()                |         |
 |        list_del()                  |         |
 |        clear_inode()               |         |
 |          inode->i_state = I_CLEAR  |         |
 |            |                       |         V
 |            |                       |      if (inode->i_state & (I_FREEING|I_WILL_FREE))
 |            |                       |              continue;           <==== NOT MATCH
 |            |                       |
 |            |                       | (DANGER from here on! Accessing disposing inode!)
 |            |                       |
 |            |                       |      __iget()
 |            |                       |        list_move() <===== PANIC on poisoned list !!
 V            V                       |
(time)
=====================================================================

Reported-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:48 -07:00
Linus Torvalds
3ae5080f4c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (37 commits)
  fs: avoid I_NEW inodes
  Merge code for single and multiple-instance mounts
  Remove get_init_pts_sb()
  Move common mknod_ptmx() calls into caller
  Parse mount options just once and copy them to super block
  Unroll essentials of do_remount_sb() into devpts
  vfs: simple_set_mnt() should return void
  fs: move bdev code out of buffer.c
  constify dentry_operations: rest
  constify dentry_operations: configfs
  constify dentry_operations: sysfs
  constify dentry_operations: JFS
  constify dentry_operations: OCFS2
  constify dentry_operations: GFS2
  constify dentry_operations: FAT
  constify dentry_operations: FUSE
  constify dentry_operations: procfs
  constify dentry_operations: ecryptfs
  constify dentry_operations: CIFS
  constify dentry_operations: AFS
  ...
2009-03-27 16:23:12 -07:00
Linus Torvalds
2c9e15a011 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6: (27 commits)
  ext2: Zero our b_size in ext2_quota_read()
  trivial: fix typos/grammar errors in fs/Kconfig
  quota: Coding style fixes
  quota: Remove superfluous inlines
  quota: Remove uppercase aliases for quota functions.
  nfsd: Use lowercase names of quota functions
  jfs: Use lowercase names of quota functions
  udf: Use lowercase names of quota functions
  ufs: Use lowercase names of quota functions
  reiserfs: Use lowercase names of quota functions
  ext4: Use lowercase names of quota functions
  ext3: Use lowercase names of quota functions
  ext2: Use lowercase names of quota functions
  ramfs: Remove quota call
  vfs: Use lowercase names of quota functions
  quota: Remove dqbuf_t and other cleanups
  quota: Remove NODQUOT macro
  quota: Make global quota locks cacheline aligned
  quota: Move quota files into separate directory
  ext4: quota reservation for delayed allocation
  ...
2009-03-27 14:48:34 -07:00
Jan Kara
268157ba67 quota: Coding style fixes
Wrap long lines, remove assignments from conditions, rewrite two
overcomplicated for loops.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:38 +01:00
Jan Kara
7a2435d874 quota: Remove superfluous inlines
Remove inlines of large functions to decrease code size (saved 1543
bytes).

Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:37 +01:00
Jan Kara
dd6f3c6d5a quota: Remove NODQUOT macro
Remove this macro which is just a definition of NULL. Fix a few coding style
issues along the way.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:35 +01:00
Jan Kara
c516610cfe quota: Make global quota locks cacheline aligned
Andrew Morton has suggested that three global quota locks can end up in the
same cacheline which can result in bad cacheline ping-pong on SMP machines.
Make locks cacheline aligned so that we avoid this problem (thanks goes to
Andrew for the idea).

Signed-off-by: Jan Kara <jack@suse.cz>
CC: Andrew Morton <akpm@linux-foundation.org>
2009-03-26 02:18:35 +01:00
Jan Kara
884d179dff quota: Move quota files into separate directory
Quota subsystem has more and more files. It's time to create a dir for it.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-03-26 02:18:35 +01:00