blk-mq: use BLK_MQ_NO_TAG in more places

Replace various magic -1 constants for tags with BLK_MQ_NO_TAG.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-mq-tag.c

@@ -92,7 +92,7 @@ static int __blk_mq_get_tag(struct blk_mq_alloc_data *data,
 {
 	if (!(data->flags & BLK_MQ_REQ_INTERNAL) &&
 	    !hctx_may_queue(data->hctx, bt))
-		return -1;
+		return BLK_MQ_NO_TAG;
 	if (data->shallow_depth)
 		return __sbitmap_queue_get_shallow(bt, data->shallow_depth);
 	else
@@ -121,7 +121,7 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
 	}
 
 	tag = __blk_mq_get_tag(data, bt);
-	if (tag != -1)
+	if (tag != BLK_MQ_NO_TAG)
 		goto found_tag;
 
 	if (data->flags & BLK_MQ_REQ_NOWAIT)
@@ -143,13 +143,13 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
 		 * as running the queue may also have found completions.
 		 */
 		tag = __blk_mq_get_tag(data, bt);
-		if (tag != -1)
+		if (tag != BLK_MQ_NO_TAG)
 			break;
 
 		sbitmap_prepare_to_wait(bt, ws, &wait, TASK_UNINTERRUPTIBLE);
 
 		tag = __blk_mq_get_tag(data, bt);
-		if (tag != -1)
+		if (tag != BLK_MQ_NO_TAG)
 			break;
 
 		bt_prev = bt;

block/blk-mq.c

@@ -278,7 +278,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 	req_flags_t rq_flags = 0;
 
 	if (data->flags & BLK_MQ_REQ_INTERNAL) {
-		rq->tag = -1;
+		rq->tag = BLK_MQ_NO_TAG;
 		rq->internal_tag = tag;
 	} else {
 		if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) {
@@ -286,7 +286,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 			atomic_inc(&data->hctx->nr_active);
 		}
 		rq->tag = tag;
-		rq->internal_tag = -1;
+		rq->internal_tag = BLK_MQ_NO_TAG;
 		data->hctx->tags->rqs[rq->tag] = rq;
 	}
 
@@ -483,9 +483,9 @@ static void __blk_mq_free_request(struct request *rq)
 	blk_crypto_free_request(rq);
 	blk_pm_mark_last_busy(rq);
 	rq->mq_hctx = NULL;
-	if (rq->tag != -1)
+	if (rq->tag != BLK_MQ_NO_TAG)
 		blk_mq_put_tag(hctx->tags, ctx, rq->tag);
-	if (sched_tag != -1)
+	if (sched_tag != BLK_MQ_NO_TAG)
 		blk_mq_put_tag(hctx->sched_tags, ctx, sched_tag);
 	blk_mq_sched_restart(hctx);
 	blk_queue_exit(q);
@@ -534,7 +534,7 @@ inline void __blk_mq_end_request(struct request *rq, blk_status_t error)
 		blk_stat_add(rq, now);
 	}
 
-	if (rq->internal_tag != -1)
+	if (rq->internal_tag != BLK_MQ_NO_TAG)
 		blk_mq_sched_completed_request(rq, now);
 
 	blk_account_io_done(rq, now);
@@ -1044,7 +1044,7 @@ bool blk_mq_get_driver_tag(struct request *rq)
 	};
 	bool shared;
 
-	if (rq->tag != -1)
+	if (rq->tag != BLK_MQ_NO_TAG)
 		return true;
 
 	if (blk_mq_tag_is_reserved(data.hctx->sched_tags, rq->internal_tag))
@@ -1060,7 +1060,7 @@ bool blk_mq_get_driver_tag(struct request *rq)
 		data.hctx->tags->rqs[rq->tag] = rq;
 	}
 
-	return rq->tag != -1;
+	return rq->tag != BLK_MQ_NO_TAG;
 }
 
 static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode,

block/blk-mq.h

@@ -201,7 +201,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
 					   struct request *rq)
 {
 	blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
-	rq->tag = -1;
+	rq->tag = BLK_MQ_NO_TAG;
 
 	if (rq->rq_flags & RQF_MQ_INFLIGHT) {
 		rq->rq_flags &= ~RQF_MQ_INFLIGHT;
@@ -211,7 +211,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
 
 static inline void blk_mq_put_driver_tag(struct request *rq)
 {
-	if (rq->tag == -1 || rq->internal_tag == -1)
+	if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
 		return;
 
 	__blk_mq_put_driver_tag(rq->mq_hctx, rq);