From: Christoph Hellwig <hch@lst.de>
Date: Wed, 2 Jun 2021 06:53:18 +0000 (+0300)
Subject: blk-mq: add the blk_mq_alloc_disk APIs
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=b461dfc49eb6fbabc60b9dad476e787ada56b7b4;p=uclinux-h8%2Flinux.git

blk-mq: add the blk_mq_alloc_disk APIs

Add a new API to allocate a gendisk including the request_queue for use
with blk-mq based drivers.  This is to avoid boilerplate code in drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210602065345.355274-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 8550ad64982f..b123077a0dc4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3137,6 +3137,25 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
 }
 EXPORT_SYMBOL(blk_mq_init_queue);
 
+struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata)
+{
+	struct request_queue *q;
+	struct gendisk *disk;
+
+	q = blk_mq_init_queue_data(set, queuedata);
+	if (IS_ERR(q))
+		return ERR_CAST(q);
+
+	disk = __alloc_disk_node(0, set->numa_node);
+	if (!disk) {
+		blk_cleanup_queue(q);
+		return ERR_PTR(-ENOMEM);
+	}
+	disk->queue = q;
+	return disk;
+}
+EXPORT_SYMBOL(__blk_mq_alloc_disk);
+
 /*
  * Helper for setting up a queue with mq ops, given queue depth, and
  * the passed in mq ops flags.
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 73750b2838d2..f496c6c5b5d2 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -426,6 +426,18 @@ enum {
 	((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \
 		<< BLK_MQ_F_ALLOC_POLICY_START_BIT)
 
+#define blk_mq_alloc_disk(set, queuedata)				\
+({									\
+	static struct lock_class_key __key;				\
+	struct gendisk *__disk = __blk_mq_alloc_disk(set, queuedata);	\
+									\
+	if (__disk)							\
+		lockdep_init_map(&__disk->lockdep_map,			\
+			"(bio completion)", &__key, 0);			\
+	__disk;								\
+})
+struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set,
+		void *queuedata);
 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
 struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set,
 		void *queuedata);