Drivers can start a freeze, so this provides a way to wait for frozen. Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxx> --- block/blk-mq.c | 3 ++- include/linux/blk-mq.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 94593c6..8da2c04 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -75,10 +75,11 @@ 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); /* * Guarantee no request is in use, so we can change any data structure of diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 001d30d..8dacf68 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -245,6 +245,7 @@ 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_reinit_tagset(struct blk_mq_tag_set *set); int blk_mq_map_queues(struct blk_mq_tag_set *set); -- 2.5.5