Merge commit '9249e17fe094d853d1ef7475dd559a2cc7e23d42' into nfs-for-3.6

Resolve conflicts with the VFS atomic open and sget changes.

Conflicts:
	fs/nfs/nfs4proc.c

1 files changed, 19 insertions, 6 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 3c923a7aeb56..93eb3e4f88ce 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -361,9 +361,10 @@ EXPORT_SYMBOL(blk_put_queue);
  */
 void blk_drain_queue(struct request_queue *q, bool drain_all)
 {
+	int i;
+
 	while (true) {
 		bool drain = false;
-		int i;
 
 		spin_lock_irq(q->queue_lock);
 
@@ -408,6 +409,18 @@ void blk_drain_queue(struct request_queue *q, bool drain_all)
 			break;
 		msleep(10);
 	}
+
+	/*
+	 * With queue marked dead, any woken up waiter will fail the
+	 * allocation path, so the wakeup chaining is lost and we're
+	 * left with hung waiters. We need to wake up those waiters.
+	 */
+	if (q->request_fn) {
+		spin_lock_irq(q->queue_lock);
+		for (i = 0; i < ARRAY_SIZE(q->rq.wait); i++)
+			wake_up_all(&q->rq.wait[i]);
+		spin_unlock_irq(q->queue_lock);
+	}
 }
 
 /**
@@ -467,7 +480,6 @@ void blk_cleanup_queue(struct request_queue *q)
 	/* mark @q DEAD, no new request or merges will be allowed afterwards */
 	mutex_lock(&q->sysfs_lock);
 	queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q);
-
 	spin_lock_irq(lock);
 
 	/*
@@ -485,10 +497,6 @@ void blk_cleanup_queue(struct request_queue *q)
 	queue_flag_set(QUEUE_FLAG_NOMERGES, q);
 	queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
 	queue_flag_set(QUEUE_FLAG_DEAD, q);
-
-	if (q->queue_lock != &q->__queue_lock)
-		q->queue_lock = &q->__queue_lock;
-
 	spin_unlock_irq(lock);
 	mutex_unlock(&q->sysfs_lock);
 
@@ -499,6 +507,11 @@ void blk_cleanup_queue(struct request_queue *q)
 	del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
 	blk_sync_queue(q);
 
+	spin_lock_irq(lock);
+	if (q->queue_lock != &q->__queue_lock)
+		q->queue_lock = &q->__queue_lock;
+	spin_unlock_irq(lock);
+
 	/* @q is and will stay empty, shutdown and put */
 	blk_put_queue(q);
 }