[PATCH 15/17] blk-mq: pass a tagset to blk_mq_wait_quiesce_done

[Christoph Hellwig]

Nothing in blk_mq_wait_quiesce_done needs the request_queue now, so just
pass the tagset, and move the non-mq check into the only caller that
needs it.

Signed-off-by: Christoph Hellwig <hch at lst.de>
Reviewed-by: Keith Busch <kbusch at kernel.org>
Reviewed-by: Sagi Grimberg <sagi at grimberg.me>
Reviewed-by: Chao Leng <lengchao at huawei.com>
Reviewed-by: Hannes Reinecke <hare at suse.de>
---
 block/blk-mq.c           | 14 ++++++++------
 drivers/nvme/host/core.c |  4 ++--
 drivers/scsi/scsi_lib.c  |  2 +-
 include/linux/blk-mq.h   |  2 +-
 4 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 6cbf34921e33f..8f88c24a55c94 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -254,15 +254,17 @@ EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue_nowait);
 
 /**
  * blk_mq_wait_quiesce_done() - wait until in-progress quiesce is done
- * @q: request queue.
+ * @set: tag_set to wait on
  *
  * Note: it is driver's responsibility for making sure that quiesce has
- * been started.
+ * been started on or more of the request_queues of the tag_set.  This
+ * function only waits for the quiesce on those request_queues that had
+ * the quiesce flag set using blk_mq_quiesce_queue_nowait.
  */
-void blk_mq_wait_quiesce_done(struct request_queue *q)
+void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set)
 {
-	if (q->tag_set->flags & BLK_MQ_F_BLOCKING)
-		synchronize_srcu(q->tag_set->srcu);
+	if (set->flags & BLK_MQ_F_BLOCKING)
+		synchronize_srcu(set->srcu);
 	else
 		synchronize_rcu();
 }
@@ -282,7 +284,7 @@ void blk_mq_quiesce_queue(struct request_queue *q)
 	blk_mq_quiesce_queue_nowait(q);
 	/* nothing to wait for non-mq queues */
 	if (queue_is_mq(q))
-		blk_mq_wait_quiesce_done(q);
+		blk_mq_wait_quiesce_done(q->tag_set);
 }
 EXPORT_SYMBOL_GPL(blk_mq_quiesce_queue);
 
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 00612e6857295..012ef0772f5b3 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -5090,7 +5090,7 @@ static void nvme_stop_ns_queue(struct nvme_ns *ns)
 	if (!test_and_set_bit(NVME_NS_STOPPED, &ns->flags))
 		blk_mq_quiesce_queue(ns->queue);
 	else
-		blk_mq_wait_quiesce_done(ns->queue);
+		blk_mq_wait_quiesce_done(ns->queue->tag_set);
 }
 
 /* let I/O to all namespaces fail in preparation for surprise removal */
@@ -5180,7 +5180,7 @@ void nvme_stop_admin_queue(struct nvme_ctrl *ctrl)
 	if (!test_and_set_bit(NVME_CTRL_ADMIN_Q_STOPPED, &ctrl->flags))
 		blk_mq_quiesce_queue(ctrl->admin_q);
 	else
-		blk_mq_wait_quiesce_done(ctrl->admin_q);
+		blk_mq_wait_quiesce_done(ctrl->admin_q->tag_set);
 }
 EXPORT_SYMBOL_GPL(nvme_stop_admin_queue);
 
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 8b89fab7c4206..249757ddd8fea 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2735,7 +2735,7 @@ static void scsi_stop_queue(struct scsi_device *sdev, bool nowait)
 			blk_mq_quiesce_queue(sdev->request_queue);
 	} else {
 		if (!nowait)
-			blk_mq_wait_quiesce_done(sdev->request_queue);
+			blk_mq_wait_quiesce_done(sdev->request_queue->tag_set);
 	}
 }
 
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index dc189d6b1a367..678ce8a661ec9 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -881,7 +881,7 @@ void blk_mq_start_hw_queues(struct request_queue *q);
 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
 void blk_mq_quiesce_queue(struct request_queue *q);
-void blk_mq_wait_quiesce_done(struct request_queue *q);
+void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set);
 void blk_mq_unquiesce_queue(struct request_queue *q);
 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
 void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
-- 
2.30.2