blk-mq: use the introduced blk_mq_unquiesce_queue()

blk_mq_unquiesce_queue() is used for unquiescing the
queue explicitly, so replace blk_mq_start_stopped_hw_queues()
with it.

For the scsi part, this patch takes Bart's suggestion to
switch to block quiesce/unquiesce API completely.

Cc: linux-nvme@lists.infradead.org
Cc: linux-scsi@vger.kernel.org
Cc: dm-devel@redhat.com
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

drivers/md/dm-rq.c

@@ -71,7 +71,7 @@ static void dm_old_start_queue(struct request_queue *q)
 
 static void dm_mq_start_queue(struct request_queue *q)
 {
-	blk_mq_start_stopped_hw_queues(q, true);
+	blk_mq_unquiesce_queue(q);
 	blk_mq_kick_requeue_list(q);
 }
 

drivers/nvme/host/core.c

@@ -2672,7 +2672,7 @@ void nvme_start_queues(struct nvme_ctrl *ctrl)
 
 	mutex_lock(&ctrl->namespaces_mutex);
 	list_for_each_entry(ns, &ctrl->namespaces, list) {
-		blk_mq_start_stopped_hw_queues(ns->queue, true);
+		blk_mq_unquiesce_queue(ns->queue);
 		blk_mq_kick_requeue_list(ns->queue);
 	}
 	mutex_unlock(&ctrl->namespaces_mutex);

drivers/scsi/scsi_lib.c

@@ -2962,7 +2962,7 @@ scsi_internal_device_block(struct scsi_device *sdev, bool wait)
 		if (wait)
 			blk_mq_quiesce_queue(q);
 		else
-			blk_mq_stop_hw_queues(q);
+			blk_mq_quiesce_queue_nowait(q);
 	} else {
 		spin_lock_irqsave(q->queue_lock, flags);
 		blk_stop_queue(q);
@@ -3016,7 +3016,7 @@ scsi_internal_device_unblock(struct scsi_device *sdev,
 		return -EINVAL;
 
 	if (q->mq_ops) {
-		blk_mq_start_stopped_hw_queues(q, false);
+		blk_mq_unquiesce_queue(q);
 	} else {
 		spin_lock_irqsave(q->queue_lock, flags);
 		blk_start_queue(q);