summaryrefslogtreecommitdiff
path: root/fs/ocfs2/file.c
diff options
context:
space:
mode:
authorWengang Wang <wen.gang.wang@oracle.com>2014-04-03 14:46:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-03 16:20:53 -0700
commitc18ceab01240fd4c354b78d877571b729908e4a3 (patch)
treed9c0107c30019e3299fe1b712d2eebaf832e55ed /fs/ocfs2/file.c
parent181a9a043b5424f2e6451297bbc27b196fe88475 (diff)
ocfs2: change ip_unaligned_aio to of type mutex from atomit_t
There is a problem that waitqueue_active() may check stale data thus miss a wakeup of threads waiting on ip_unaligned_aio. The valid value of ip_unaligned_aio is only 0 and 1 so we can change it to be of type mutex thus the above prolem is avoid. Another benifit is that mutex which works as FIFO is fairer than wake_up_all(). Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ocfs2/file.c')
-rw-r--r--fs/ocfs2/file.c15
1 files changed, 3 insertions, 12 deletions
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 51632c40e896..1673438789fe 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2061,13 +2061,6 @@ out:
return ret;
}
-static void ocfs2_aiodio_wait(struct inode *inode)
-{
- wait_queue_head_t *wq = ocfs2_ioend_wq(inode);
-
- wait_event(*wq, (atomic_read(&OCFS2_I(inode)->ip_unaligned_aio) == 0));
-}
-
static int ocfs2_is_io_unaligned(struct inode *inode, size_t count, loff_t pos)
{
int blockmask = inode->i_sb->s_blocksize - 1;
@@ -2345,10 +2338,8 @@ relock:
* Wait on previous unaligned aio to complete before
* proceeding.
*/
- ocfs2_aiodio_wait(inode);
-
- /* Mark the iocb as needing a decrement in ocfs2_dio_end_io */
- atomic_inc(&OCFS2_I(inode)->ip_unaligned_aio);
+ mutex_lock(&OCFS2_I(inode)->ip_unaligned_aio);
+ /* Mark the iocb as needing an unlock in ocfs2_dio_end_io */
ocfs2_iocb_set_unaligned_aio(iocb);
}
@@ -2428,7 +2419,7 @@ out_dio:
if (unaligned_dio) {
ocfs2_iocb_clear_unaligned_aio(iocb);
- atomic_dec(&OCFS2_I(inode)->ip_unaligned_aio);
+ mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
}
out: