Commit f525464a authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: add blk_alloc_disk and blk_cleanup_disk APIs 



Add two new APIs to allocate and free a gendisk including the
request_queue for use with BIO based drivers.  This is to avoid
boilerplate code in drivers.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-6-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 958229a7

block/genhd.c

+35 −0
Original line number Diff line number Diff line
@@ -1293,6 +1293,25 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) 
}

EXPORT_SYMBOL(__alloc_disk_node);



struct gendisk *__blk_alloc_disk(int node)

{

	struct request_queue *q;

	struct gendisk *disk;



	q = blk_alloc_queue(node);

	if (!q)

		return NULL;



	disk = __alloc_disk_node(0, node);

	if (!disk) {

		blk_cleanup_queue(q);

		return NULL;

	}

	disk->queue = q;

	return disk;

}

EXPORT_SYMBOL(__blk_alloc_disk);



/**

 * put_disk - decrements the gendisk refcount

 * @disk: the struct gendisk to decrement the refcount for
@@ -1310,6 +1329,22 @@ void put_disk(struct gendisk *disk) 
}

EXPORT_SYMBOL(put_disk);



/**

 * blk_cleanup_disk - shutdown a gendisk allocated by blk_alloc_disk

 * @disk: gendisk to shutdown

 *

 * Mark the queue hanging off @disk DYING, drain all pending requests, then mark

 * the queue DEAD, destroy and put it and the gendisk structure.

 *

 * Context: can sleep

 */

void blk_cleanup_disk(struct gendisk *disk)

{

	blk_cleanup_queue(disk->queue);

	put_disk(disk);

}

EXPORT_SYMBOL(blk_cleanup_disk);



static void set_disk_ro_uevent(struct gendisk *gd, int ro)

{

	char event[] = "DISK_RO=1";

include/linux/genhd.h

+22 −0
Original line number Diff line number Diff line
@@ -278,6 +278,28 @@ extern void put_disk(struct gendisk *disk); 


#define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)



/**

 * blk_alloc_disk - allocate a gendisk structure

 * @node_id: numa node to allocate on

 *

 * Allocate and pre-initialize a gendisk structure for use with BIO based

 * drivers.

 *

 * Context: can sleep

 */

#define blk_alloc_disk(node_id)						\

({									\

	struct gendisk *__disk = __blk_alloc_disk(node_id);		\

	static struct lock_class_key __key;				\

									\

	if (__disk)							\

		lockdep_init_map(&__disk->lockdep_map,			\

			"(bio completion)", &__key, 0);			\

	__disk;								\

})

struct gendisk *__blk_alloc_disk(int node);

void blk_cleanup_disk(struct gendisk *disk);



int __register_blkdev(unsigned int major, const char *name,

		void (*probe)(dev_t devt));

#define register_blkdev(major, name) \