[PATCH v1 3/9] blk-mq: export blk_mq_freeze_queue and blk_mq_unfreeze_queue

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

It is handy to use the two helpers for switching backend file
in loop driver, so export them.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
 block/blk-mq.c         |    4 +++-
 block/blk-mq.h         |    1 -
 include/linux/blk-mq.h |    2 ++
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 5189cb1..07e1033 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -120,8 +120,9 @@ void blk_mq_freeze_queue(struct request_queue *q)
 	blk_mq_run_queues(q, false);
 	wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter));
 }
+EXPORT_SYMBOL(blk_mq_freeze_queue);
 
-static void blk_mq_unfreeze_queue(struct request_queue *q)
+void blk_mq_unfreeze_queue(struct request_queue *q)
 {
 	bool wake = false;
 
@@ -134,6 +135,7 @@ static void blk_mq_unfreeze_queue(struct request_queue *q)
 		wake_up_all(&q->mq_freeze_wq);
 	}
 }
+EXPORT_SYMBOL(blk_mq_unfreeze_queue);
 
 bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx)
 {
diff --git a/block/blk-mq.h b/block/blk-mq.h
index ca4964a..3800316 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -28,7 +28,6 @@ struct blk_mq_ctx {
 void __blk_mq_complete_request(struct request *rq);
 void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
 void blk_mq_init_flush(struct request_queue *q);
-void blk_mq_freeze_queue(struct request_queue *q);
 void blk_mq_free_queue(struct request_queue *q);
 void blk_mq_clone_flush_request(struct request *flush_rq,
 		struct request *orig_rq);
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index eb726b9..1cc1baa 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -175,6 +175,8 @@ void blk_mq_start_hw_queues(struct request_queue *q);
 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
 void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
 void blk_mq_tag_busy_iter(struct blk_mq_tags *tags, void (*fn)(void *data, unsigned long *), void *data);
+void blk_mq_freeze_queue(struct request_queue *q);
+void blk_mq_unfreeze_queue(struct request_queue *q);
 
 /*
  * Driver command data is immediately after the request. So subtract request
-- 
1.7.9.5