ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang
authorJunxiao Bi <junxiao.bi@oracle.com>
Thu, 12 May 2016 22:42:15 +0000 (15:42 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 12 May 2016 22:52:50 +0000 (15:52 -0700)
commit5ee0fbd50fdf1c1329de8bee35ea9d7c6a81a2e0
treead5472be43466ea27f8a6804f0de9a8631d67cc6
parent422ce5a97570cb8a37d016b6bc2021ae4dac5499
ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang

Commit 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
introduced this issue.  ocfs2_setattr called by chmod command holds
cluster wide inode lock when calling posix_acl_chmod.  This latter
function in turn calls ocfs2_iop_get_acl and ocfs2_iop_set_acl.  These
two are also called directly from vfs layer for getfacl/setfacl commands
and therefore acquire the cluster wide inode lock.  If a remote
conversion request comes after the first inode lock in ocfs2_setattr,
OCFS2_LOCK_BLOCKED will be set.  And this will cause the second call to
inode lock from the ocfs2_iop_get_acl() to block indefinetly.

The deleted version of ocfs2_acl_chmod() calls __posix_acl_chmod() which
does not call back into the filesystem.  Therefore, we restore
ocfs2_acl_chmod(), modify it slightly for locking as needed, and use that
instead.

Fixes: 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
Signed-off-by: Tariq Saeed <tariq.x.saeed@oracle.com>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ocfs2/acl.c
fs/ocfs2/acl.h
fs/ocfs2/file.c