1 files changed, 25 insertions, 52 deletions

diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c
index dc75bea0d541..9d7275fb541a 100644
--- a/drivers/md/dm-rq.c
+++ b/drivers/md/dm-rq.c
@@ -23,11 +23,7 @@ static unsigned dm_mq_queue_depth = DM_MQ_QUEUE_DEPTH;
 #define RESERVED_REQUEST_BASED_IOS	256
 static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS;
 
-#ifdef CONFIG_DM_MQ_DEFAULT
-static bool use_blk_mq = true;
-#else
-static bool use_blk_mq = false;
-#endif
+static bool use_blk_mq = IS_ENABLED(CONFIG_DM_MQ_DEFAULT);
 
 bool dm_use_blk_mq_default(void)
 {
@@ -75,12 +71,6 @@ static void dm_old_start_queue(struct request_queue *q)
 
 static void dm_mq_start_queue(struct request_queue *q)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-	queue_flag_clear(QUEUE_FLAG_STOPPED, q);
-	spin_unlock_irqrestore(q->queue_lock, flags);
-
 	blk_mq_start_stopped_hw_queues(q, true);
 	blk_mq_kick_requeue_list(q);
 }
@@ -105,20 +95,10 @@ static void dm_old_stop_queue(struct request_queue *q)
 
 static void dm_mq_stop_queue(struct request_queue *q)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-	if (blk_queue_stopped(q)) {
-		spin_unlock_irqrestore(q->queue_lock, flags);
+	if (blk_mq_queue_stopped(q))
 		return;
-	}
 
-	queue_flag_set(QUEUE_FLAG_STOPPED, q);
-	spin_unlock_irqrestore(q->queue_lock, flags);
-
-	/* Avoid that requeuing could restart the queue. */
-	blk_mq_cancel_requeue_work(q);
-	blk_mq_stop_hw_queues(q);
+	blk_mq_quiesce_queue(q);
 }
 
 void dm_stop_queue(struct request_queue *q)
@@ -226,6 +206,9 @@ static void rq_end_stats(struct mapped_device *md, struct request *orig)
  */
 static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
 {
+	struct request_queue *q = md->queue;
+	unsigned long flags;
+
 	atomic_dec(&md->pending[rw]);
 
 	/* nudge anyone waiting on suspend queue */
@@ -238,8 +221,11 @@ static void rq_completed(struct mapped_device *md, int rw, bool run_queue)
 	 * back into ->request_fn() could deadlock attempting to grab the
 	 * queue lock again.
 	 */
-	if (!md->queue->mq_ops && run_queue)
-		blk_run_queue_async(md->queue);
+	if (!q->mq_ops && run_queue) {
+		spin_lock_irqsave(q->queue_lock, flags);
+		blk_run_queue_async(q);
+		spin_unlock_irqrestore(q->queue_lock, flags);
+	}
 
 	/*
 	 * dm_put() must be at the end of this function. See the comment above
@@ -313,7 +299,7 @@ static void dm_unprep_request(struct request *rq)
 
 	if (!rq->q->mq_ops) {
 		rq->special = NULL;
-		rq->cmd_flags &= ~REQ_DONTPREP;
+		rq->rq_flags &= ~RQF_DONTPREP;
 	}
 
 	if (clone)
@@ -338,12 +324,7 @@ static void dm_old_requeue_request(struct request *rq)
 
 static void __dm_mq_kick_requeue_list(struct request_queue *q, unsigned long msecs)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-	if (!blk_queue_stopped(q))
-		blk_mq_delay_kick_requeue_list(q, msecs);
-	spin_unlock_irqrestore(q->queue_lock, flags);
+	blk_mq_delay_kick_requeue_list(q, msecs);
 }
 
 void dm_mq_kick_requeue_list(struct mapped_device *md)
@@ -354,7 +335,7 @@ EXPORT_SYMBOL(dm_mq_kick_requeue_list);
 
 static void dm_mq_delay_requeue_request(struct request *rq, unsigned long msecs)
 {
-	blk_mq_requeue_request(rq);
+	blk_mq_requeue_request(rq, false);
 	__dm_mq_kick_requeue_list(rq->q, msecs);
 }
 
@@ -431,7 +412,7 @@ static void dm_softirq_done(struct request *rq)
 		return;
 	}
 
-	if (rq->cmd_flags & REQ_FAILED)
+	if (rq->rq_flags & RQF_FAILED)
 		mapped = false;
 
 	dm_done(clone, tio->error, mapped);
@@ -460,7 +441,7 @@ static void dm_complete_request(struct request *rq, int error)
  */
 static void dm_kill_unmapped_request(struct request *rq, int error)
 {
-	rq->cmd_flags |= REQ_FAILED;
+	rq->rq_flags |= RQF_FAILED;
 	dm_complete_request(rq, error);
 }
 
@@ -476,7 +457,7 @@ static void end_clone_request(struct request *clone, int error)
 		 * For just cleaning up the information of the queue in which
 		 * the clone was dispatched.
 		 * The clone is *NOT* freed actually here because it is alloced
-		 * from dm own mempool (REQ_ALLOCED isn't set).
+		 * from dm own mempool (RQF_ALLOCED isn't set).
 		 */
 		__blk_put_request(clone->q, clone);
 	}
@@ -497,7 +478,7 @@ static void dm_dispatch_clone_request(struct request *clone, struct request *rq)
 	int r;
 
 	if (blk_queue_io_stat(clone->q))
-		clone->cmd_flags |= REQ_IO_STAT;
+		clone->rq_flags |= RQF_IO_STAT;
 
 	clone->start_time = jiffies;
 	r = blk_insert_cloned_request(clone->q, clone);
@@ -633,7 +614,7 @@ static int dm_old_prep_fn(struct request_queue *q, struct request *rq)
 		return BLKPREP_DEFER;
 
 	rq->special = tio;
-	rq->cmd_flags |= REQ_DONTPREP;
+	rq->rq_flags |= RQF_DONTPREP;
 
 	return BLKPREP_OK;
 }
@@ -819,7 +800,7 @@ static void dm_old_request_fn(struct request_queue *q)
 			pos = blk_rq_pos(rq);
 
 		if ((dm_old_request_peeked_before_merge_deadline(md) &&
-		     md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
+		     md_in_flight(md) && rq->bio && !bio_multiple_segments(rq->bio) &&
 		     md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
 		    (ti->type->busy && ti->type->busy(ti))) {
 			blk_delay_queue(q, 10);
@@ -856,8 +837,11 @@ int dm_old_init_request_queue(struct mapped_device *md)
 	kthread_init_worker(&md->kworker);
 	md->kworker_task = kthread_run(kthread_worker_fn, &md->kworker,
 				       "kdmwork-%s", dm_device_name(md));
-	if (IS_ERR(md->kworker_task))
-		return PTR_ERR(md->kworker_task);
+	if (IS_ERR(md->kworker_task)) {
+		int error = PTR_ERR(md->kworker_task);
+		md->kworker_task = NULL;
+		return error;
+	}
 
 	elv_register_queue(md->queue);
 
@@ -901,17 +885,6 @@ static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 		dm_put_live_table(md, srcu_idx);
 	}
 
-	/*
-	 * On suspend dm_stop_queue() handles stopping the blk-mq
-	 * request_queue BUT: even though the hw_queues are marked
-	 * BLK_MQ_S_STOPPED at that point there is still a race that
-	 * is allowing block/blk-mq.c to call ->queue_rq against a
-	 * hctx that it really shouldn't.  The following check guards
-	 * against this rarity (albeit _not_ race-free).
-	 */
-	if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state)))
-		return BLK_MQ_RQ_QUEUE_BUSY;
-
 	if (ti->type->busy && ti->type->busy(ti))
 		return BLK_MQ_RQ_QUEUE_BUSY;