Commit a21f9edb authored by Benjamin Marzinski's avatar Benjamin Marzinski Committed by Mikulas Patocka
Browse files

dm: factor out helper function from dm_get_device 



Factor out a helper function, dm_devt_from_path(), from dm_get_device()
for use in dm targets.

Signed-off-by: default avatarBenjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
parent 3708c726

drivers/md/dm-table.c

+24 −9
Original line number Diff line number Diff line
@@ -331,23 +331,15 @@ static int upgrade_mode(struct dm_dev_internal *dd, blk_mode_t new_mode, 
}



/*

 * Add a device to the list, or just increment the usage count if

 * it's already present.

 *

 * Note: the __ref annotation is because this function can call the __init

 * marked early_lookup_bdev when called during early boot code from dm-init.c.

 */

int __ref dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode,

		  struct dm_dev **result)

int __ref dm_devt_from_path(const char *path, dev_t *dev_p)

{

	int r;

	dev_t dev;

	unsigned int major, minor;

	char dummy;

	struct dm_dev_internal *dd;

	struct dm_table *t = ti->table;



	BUG_ON(!t);



	if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) {

		/* Extract the major/minor numbers */
@@ -363,6 +355,29 @@ int __ref dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode, 
		if (r)

			return r;

	}

	*dev_p = dev;

	return 0;

}

EXPORT_SYMBOL(dm_devt_from_path);



/*

 * Add a device to the list, or just increment the usage count if

 * it's already present.

 */

int dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode,

		  struct dm_dev **result)

{

	int r;

	dev_t dev;

	struct dm_dev_internal *dd;

	struct dm_table *t = ti->table;



	BUG_ON(!t);



	r = dm_devt_from_path(path, &dev);

	if (r)

		return r;



	if (dev == disk_devt(t->md->disk))

		return -EINVAL;

include/linux/device-mapper.h

+5 −0
Original line number Diff line number Diff line
@@ -179,6 +179,11 @@ int dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode, 
		  struct dm_dev **result);

void dm_put_device(struct dm_target *ti, struct dm_dev *d);



/*

 * Helper function for getting devices

 */

int dm_devt_from_path(const char *path, dev_t *dev_p);



/*

 * Information about a target type

 */