[PATCH 07/14] block: pass a queue_limits argument to blk_alloc_queue

[Christoph Hellwig]

Pass a queue_limits to blk_alloc_queue and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Signed-off-by: Christoph Hellwig <hch at lst.de>
Reviewed-by: John Garry <john.g.garry at oracle.com>
Reviewed-by: Damien Le Moal <dlemoal at kernel.org>
Reviewed-by: Hannes Reinecke <hare at suse.de>
---
 block/blk-core.c | 30 ++++++++++++++++++++++--------
 block/blk-mq.c   |  6 +++---
 block/blk.h      |  2 +-
 block/genhd.c    |  4 ++--
 4 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 09f4a44a4aa3cc..26d3be06bcc0fd 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -393,24 +393,38 @@ static void blk_timeout_work(struct work_struct *work)
 {
 }
 
-struct request_queue *blk_alloc_queue(int node_id)
+struct request_queue *blk_alloc_queue(struct queue_limits *lim, int node_id)
 {
 	struct request_queue *q;
+	int error;
 
 	q = kmem_cache_alloc_node(blk_requestq_cachep, GFP_KERNEL | __GFP_ZERO,
 				  node_id);
 	if (!q)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	q->last_merge = NULL;
 
+	if (lim) {
+		error = blk_validate_limits(lim);
+		if (error)
+			goto fail_q;
+		q->limits = *lim;
+	} else {
+		blk_set_default_limits(&q->limits);
+	}
+
 	q->id = ida_alloc(&blk_queue_ida, GFP_KERNEL);
-	if (q->id < 0)
+	if (q->id < 0) {
+		error = q->id;
 		goto fail_q;
+	}
 
 	q->stats = blk_alloc_queue_stats();
-	if (!q->stats)
+	if (!q->stats) {
+		error = -ENOMEM;
 		goto fail_id;
+	}
 
 	q->node = node_id;
 
@@ -435,12 +449,12 @@ struct request_queue *blk_alloc_queue(int node_id)
 	 * Init percpu_ref in atomic mode so that it's faster to shutdown.
 	 * See blk_register_queue() for details.
 	 */
-	if (percpu_ref_init(&q->q_usage_counter,
+	error = percpu_ref_init(&q->q_usage_counter,
 				blk_queue_usage_counter_release,
-				PERCPU_REF_INIT_ATOMIC, GFP_KERNEL))
+				PERCPU_REF_INIT_ATOMIC, GFP_KERNEL);
+	if (error)
 		goto fail_stats;
 
-	blk_set_default_limits(&q->limits);
 	q->nr_requests = BLKDEV_DEFAULT_RQ;
 
 	return q;
@@ -451,7 +465,7 @@ struct request_queue *blk_alloc_queue(int node_id)
 	ida_free(&blk_queue_ida, q->id);
 fail_q:
 	kmem_cache_free(blk_requestq_cachep, q);
-	return NULL;
+	return ERR_PTR(error);
 }
 
 /**
diff --git a/block/blk-mq.c b/block/blk-mq.c
index aa87fcfda1ecfc..2ddbefdeae93e4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -4092,9 +4092,9 @@ static struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set,
 	struct request_queue *q;
 	int ret;
 
-	q = blk_alloc_queue(set->numa_node);
-	if (!q)
-		return ERR_PTR(-ENOMEM);
+	q = blk_alloc_queue(NULL, set->numa_node);
+	if (IS_ERR(q))
+		return q;
 	q->queuedata = queuedata;
 	ret = blk_mq_init_allocated_queue(set, q);
 	if (ret) {
diff --git a/block/blk.h b/block/blk.h
index 58b5dbac2a487d..100c7a02854bfd 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -448,7 +448,7 @@ static inline void bio_release_page(struct bio *bio, struct page *page)
 }
 
 int blk_validate_limits(struct queue_limits *lim);
-struct request_queue *blk_alloc_queue(int node_id);
+struct request_queue *blk_alloc_queue(struct queue_limits *lim, int node_id);
 
 int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode);
 
diff --git a/block/genhd.c b/block/genhd.c
index d74fb5b4ae6818..defcd35b421bdd 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1396,8 +1396,8 @@ struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass)
 	struct request_queue *q;
 	struct gendisk *disk;
 
-	q = blk_alloc_queue(node);
-	if (!q)
+	q = blk_alloc_queue(NULL, node);
+	if (IS_ERR(q))
 		return NULL;
 
 	disk = __alloc_disk_node(q, node, lkclass);
-- 
2.39.2