ocfs2: avoid blocking in ocfs2_mark_lockres_freeing() in downconvert thread

If we are dropping last inode reference from downconvert thread, we will
end up calling ocfs2_mark_lockres_freeing() which can block if the lock
we are freeing is queued thus creating an A-A deadlock.  Luckily, since
we are the downconvert thread, we can immediately dequeue the lock and
thus avoid waiting in this case.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.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>
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 809b5d5..d437f3b 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -1080,6 +1080,7 @@
 {
 	int status;
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
+	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
 	clear_inode(inode);
 	trace_ocfs2_clear_inode((unsigned long long)oi->ip_blkno,
@@ -1096,9 +1097,9 @@
 
 	/* Do these before all the other work so that we don't bounce
 	 * the downconvert thread while waiting to destroy the locks. */
-	ocfs2_mark_lockres_freeing(&oi->ip_rw_lockres);
-	ocfs2_mark_lockres_freeing(&oi->ip_inode_lockres);
-	ocfs2_mark_lockres_freeing(&oi->ip_open_lockres);
+	ocfs2_mark_lockres_freeing(osb, &oi->ip_rw_lockres);
+	ocfs2_mark_lockres_freeing(osb, &oi->ip_inode_lockres);
+	ocfs2_mark_lockres_freeing(osb, &oi->ip_open_lockres);
 
 	ocfs2_resv_discard(&OCFS2_SB(inode->i_sb)->osb_la_resmap,
 			   &oi->ip_la_data_resv);