ocfs2: unlock super lock if lockres refresh failed

commit 3278bb74 upstream.

If lockres refresh failed, the super lock will never be released which
will cause some processes on other cluster nodes hung forever.
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

fs/ocfs2/dlmglue.c

@@ -2545,6 +2545,7 @@ int ocfs2_super_lock(struct ocfs2_super *osb,
 	 * everything is up to the caller :) */
 	status = ocfs2_should_refresh_lock_res(lockres);
 	if (status < 0) {
+		ocfs2_cluster_unlock(osb, lockres, level);
 		mlog_errno(status);
 		goto bail;
 	}
@@ -2553,8 +2554,10 @@ int ocfs2_super_lock(struct ocfs2_super *osb,
 
 		ocfs2_complete_lock_res_refresh(lockres, status);
 
-		if (status < 0)
+		if (status < 0) {
+			ocfs2_cluster_unlock(osb, lockres, level);
 			mlog_errno(status);
+		}
 		ocfs2_track_lock_refresh(lockres);
 	}
 bail: