Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 04077599 authored by Ilya Dryomov's avatar Ilya Dryomov
Browse files

rbd: split rbd_dev_spec_update() into two functions 



rbd_dev_spec_update() has two modes of operation, with nothing in
common between them.  Split it into two functions, one for each mode
and make our expectations more clear.

Signed-off-by: default avatarIlya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: default avatarAlex Elder <elder@linaro.org>
parent 7626eb7d

drivers/block/rbd.c

+48 −31
Original line number Diff line number Diff line
@@ -3798,6 +3798,9 @@ static struct rbd_spec *rbd_spec_alloc(void) 
	spec = kzalloc(sizeof (*spec), GFP_KERNEL);

	if (!spec)

		return NULL;



	spec->pool_id = CEPH_NOPOOL;

	spec->snap_id = CEPH_NOSNAP;

	kref_init(&spec->kref);



	return spec;
@@ -4257,37 +4260,23 @@ static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 
}



/*

 * When an rbd image has a parent image, it is identified by the

 * pool, image, and snapshot ids (not names).  This function fills

 * in the names for those ids.  (It's OK if we can't figure out the

 * name for an image id, but the pool and snapshot ids should always

 * exist and have names.)  All names in an rbd spec are dynamically

 * allocated.

 *

 * When an image being mapped (not a parent) is probed, we have the

 * pool name and pool id, image name and image id, and the snapshot

 * name.  The only thing we're missing is the snapshot id.

 * An image being mapped will have everything but the snap id.

 */

static int rbd_dev_spec_update(struct rbd_device *rbd_dev)

static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)

{

	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;

	struct rbd_spec *spec = rbd_dev->spec;

	const char *pool_name;

	const char *image_name;

	const char *snap_name;

	int ret;



	/*

	 * An image being mapped will have the pool name (etc.), but

	 * we need to look up the snapshot id.

	 */

	if (spec->pool_name) {

	rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);

	rbd_assert(spec->image_id && spec->image_name);

	rbd_assert(spec->snap_name);



	if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {

		u64 snap_id;



		snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);

		if (snap_id == CEPH_NOSNAP)

			return -ENOENT;



		spec->snap_id = snap_id;

	} else {

		spec->snap_id = CEPH_NOSNAP;
@@ -4296,6 +4285,25 @@ static int rbd_dev_spec_update(struct rbd_device *rbd_dev) 
	return 0;

}



/*

 * A parent image will have all ids but none of the names.

 *

 * All names in an rbd spec are dynamically allocated.  It's OK if we

 * can't figure out the name for an image id.

 */

static int rbd_spec_fill_names(struct rbd_device *rbd_dev)

{

	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;

	struct rbd_spec *spec = rbd_dev->spec;

	const char *pool_name;

	const char *image_name;

	const char *snap_name;

	int ret;



	rbd_assert(spec->pool_id != CEPH_NOPOOL);

	rbd_assert(spec->image_id);

	rbd_assert(spec->snap_id != CEPH_NOSNAP);



	/* Get the pool name; we have to make our own copy of this */



	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
@@ -4313,7 +4321,7 @@ static int rbd_dev_spec_update(struct rbd_device *rbd_dev) 
	if (!image_name)

		rbd_warn(rbd_dev, "unable to get image name");



	/* Look up the snapshot name, and make a copy */

	/* Fetch the snapshot name */



	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);

	if (IS_ERR(snap_name)) {
@@ -4326,10 +4334,10 @@ static int rbd_dev_spec_update(struct rbd_device *rbd_dev) 
	spec->snap_name = snap_name;



	return 0;



out_err:

	kfree(image_name);

	kfree(pool_name);



	return ret;

}
@@ -5158,7 +5166,16 @@ static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping) 
	if (ret)

		goto err_out_watch;



	ret = rbd_dev_spec_update(rbd_dev);

	/*

	 * If this image is the one being mapped, we have pool name and

	 * id, image name and id, and snap name - need to fill snap id.

	 * Otherwise this is a parent image, identified by pool, image

	 * and snap ids - need to fill in names for those ids.

	 */

	if (mapping)

		ret = rbd_spec_fill_snap_id(rbd_dev);

	else

		ret = rbd_spec_fill_names(rbd_dev);

	if (ret)

		goto err_out_probe;