blk-mq: Export blk_mq_freeze_queue_wait

Drivers can start a freeze, so this provides a way to wait for frozen.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit 6bae363ee3057a14eec93440826813603559273a)

Orabug: 26486098

Signed-off-by: Ashok Vairavan <ashok.vairavan@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index bebb92640a6c9efbd7242900e4904bfb6c90d5ef..ed0a92268c7627b384c84e00958220b48557e0fd 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -89,10 +89,11 @@ void blk_mq_freeze_queue_start(struct request_queue *q)
 }
 EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_start);
 
-static void blk_mq_freeze_queue_wait(struct request_queue *q)
+void blk_mq_freeze_queue_wait(struct request_queue *q)
 {
        wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->q_usage_counter));
 }
+EXPORT_SYMBOL_GPL(blk_mq_freeze_queue_wait);
 
 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
                                     unsigned long timeout)

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 6de02be8f349de27b9ca95b4de0f9c9350830307..de01a0710b457e76758472b4ca6d608f43ba9ca9 100644 (file)
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -238,6 +238,7 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
 void blk_mq_freeze_queue(struct request_queue *q);
 void blk_mq_unfreeze_queue(struct request_queue *q);
 void blk_mq_freeze_queue_start(struct request_queue *q);
+void blk_mq_freeze_queue_wait(struct request_queue *q);
 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
                                     unsigned long timeout);