1 files changed, 15 insertions, 1 deletions

diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index 251c48028ea3..a65a87726d6a 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -2707,8 +2707,15 @@ static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm,
         __dlm_lockres_reserve_ast(res);
         spin_unlock(&res->spinlock);
 
-        /* now flush all the pending asts.. hang out for a bit */
+        /* now flush all the pending asts */
         dlm_kick_thread(dlm, res);
+        /* before waiting on DIRTY, block processes which may
+         * try to dirty the lockres before MIGRATING is set */
+        spin_lock(&res->spinlock);
+        BUG_ON(res->state & DLM_LOCK_RES_BLOCK_DIRTY);
+        res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
+        spin_unlock(&res->spinlock);
+        /* now wait on any pending asts and the DIRTY state */
         wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
         dlm_lockres_release_ast(dlm, res);
 
@@ -2734,6 +2741,13 @@ again:
                 mlog(0, "trying again...\n");
                 goto again;
         }
+        /* now that we are sure the MIGRATING state is there, drop
+         * the unneded state which blocked threads trying to DIRTY */
+        spin_lock(&res->spinlock);
+        BUG_ON(!(res->state & DLM_LOCK_RES_BLOCK_DIRTY));
+        BUG_ON(!(res->state & DLM_LOCK_RES_MIGRATING));
+        res->state &= ~DLM_LOCK_RES_BLOCK_DIRTY;
+        spin_unlock(&res->spinlock);
 
         /* did the target go down or die? */
         spin_lock(&dlm->spinlock);