ocfs2: Do not downconvert if the lock level is already compatible

[deliverable/linux.git] / fs / ocfs2 / dlmglue.c

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 85d7c490755bf985f1b5eda7932a50428a7a3ade..ac24f49ae2fb0ac489cca96af8579ee6aebd7399 100644 (file)
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -3445,6 +3445,19 @@ recheck:
        if (lockres->l_flags & OCFS2_LOCK_UPCONVERT_FINISHING)
                goto leave_requeue;
 
+       /*
+        * How can we block and yet be at NL?  We were trying to upconvert
+        * from NL and got canceled.  The code comes back here, and now
+        * we notice and clear BLOCKING.
+        */
+       if (lockres->l_level == DLM_LOCK_NL) {
+               BUG_ON(lockres->l_ex_holders || lockres->l_ro_holders);
+               lockres->l_blocking = DLM_LOCK_NL;
+               lockres_clear_flags(lockres, OCFS2_LOCK_BLOCKED);
+               spin_unlock_irqrestore(&lockres->l_lock, flags);
+               goto leave;
+       }
+
        /* if we're blocking an exclusive and we have *any* holders,
         * then requeue. */
        if ((lockres->l_blocking == DLM_LOCK_EX)