[PATCH v4 03/11] blk-mq: introduce blk_mq_quiesce_queue_nowait()

[Ming Lei <ming.lei@redhat.com>]

This patch introduces blk_mq_quiesce_queue_nowait() so
that we can workaround mpt3sas for quiescing its queue.

Once mpt3sas is fixed, we can remove this helper.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 include/linux/blk-mq.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 1e480015d172..13d1196f492f 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -266,6 +266,14 @@ int blk_mq_map_queues(struct blk_mq_tag_set *set);
 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
 
 /*
+ * FIXME: this helper is just for working around mpt3sas.
+ */
+static inline void blk_mq_quiesce_queue_nowait(struct request_queue *q)
+{
+	blk_mq_stop_hw_queues(q);
+}
+
+/*
  * Driver command data is immediately after the request. So subtract request
  * size to get back to the original request, add request size to get the PDU.
  */
-- 
2.9.4