diff options
| author | Dave Chinner <dchinner@redhat.com> | 2011-03-22 22:23:36 +1100 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2011-03-24 21:16:31 -0400 |
| commit | 250df6ed274d767da844a5d9f05720b804240197 (patch) | |
| tree | b74f49a86c4451d9e3e82f90e3f791163025be21 /fs/quota | |
| parent | 3dc8fe4dca9cd3e4aa828ed36451e2bcfd2350da (diff) | |
| download | linux-250df6ed274d767da844a5d9f05720b804240197.tar.bz2 | |
fs: protect inode->i_state with inode->i_lock
Protect inode state transitions and validity checks with the
inode->i_lock. This enables us to make inode state transitions
independently of the inode_lock and is the first step to peeling
away the inode_lock from the code.
This requires that __iget() is done atomically with i_state checks
during list traversals so that we don't race with another thread
marking the inode I_FREEING between the state check and grabbing the
reference.
Also remove the unlock_new_inode() memory barrier optimisation
required to avoid taking the inode_lock when clearing I_NEW.
Simplify the code by simply taking the inode->i_lock around the
state change and wakeup. Because the wakeup is no longer tricky,
remove the wake_up_inode() function and open code the wakeup where
necessary.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/quota')
| -rw-r--r-- | fs/quota/dquot.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index a2a622e079f0..a1470fda366c 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -902,18 +902,19 @@ static void add_dquot_ref(struct super_block *sb, int type) spin_lock(&inode_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { - if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) + spin_lock(&inode->i_lock); + if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || + !atomic_read(&inode->i_writecount) || + !dqinit_needed(inode, type)) { + spin_unlock(&inode->i_lock); continue; + } #ifdef CONFIG_QUOTA_DEBUG if (unlikely(inode_get_rsv_space(inode) > 0)) reserved = 1; #endif - if (!atomic_read(&inode->i_writecount)) - continue; - if (!dqinit_needed(inode, type)) - continue; - __iget(inode); + spin_unlock(&inode->i_lock); spin_unlock(&inode_lock); iput(old_inode); |