ocfs2/dlm: fix race between convert and recovery

[pandora-kernel.git] / fs / ocfs2 / dlm / dlmconvert.c

diff --git a/fs/ocfs2/dlm/dlmconvert.c b/fs/ocfs2/dlm/dlmconvert.c
index 29a886d..093200f 100644 (file)
--- a/fs/ocfs2/dlm/dlmconvert.c
+++ b/fs/ocfs2/dlm/dlmconvert.c
@@ -265,6 +265,7 @@ enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
                                  struct dlm_lock *lock, int flags, int type)
 {
        enum dlm_status status;
+       u8 old_owner = res->owner;
 
        mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
             lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
@@ -319,11 +320,19 @@ enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
        spin_lock(&res->spinlock);
        res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
        lock->convert_pending = 0;
-       /* if it failed, move it back to granted queue */
+       /* if it failed, move it back to granted queue.
+        * if master returns DLM_NORMAL and then down before sending ast,
+        * it may have already been moved to granted queue, reset to
+        * DLM_RECOVERING and retry convert */
        if (status != DLM_NORMAL) {
                if (status != DLM_NOTQUEUED)
                        dlm_error(status);
                dlm_revert_pending_convert(res, lock);
+       } else if ((res->state & DLM_LOCK_RES_RECOVERING) ||
+                       (old_owner != res->owner)) {
+               mlog(0, "res %.*s is in recovering or has been recovered.\n",
+                               res->lockname.len, res->lockname.name);
+               status = DLM_RECOVERING;
        }
 bail:
        spin_unlock(&res->spinlock);