Commit 34b13184 authored by Alex Elder's avatar Alex Elder
Browse files

rbd: add an rbd features field 



Record the features values for each rbd image and each of its
snapshots.  This is really something that only becomes meaningful
for version 2 images, so this is just putting in place code
that will form common infrastructure.

It may be useful to expand the sysfs entries--and therefore the
information we maintain--for the image and for each snapshot.
But I'm going to hold off doing that until we start making
active use of the feature bits.

Signed-off-by: default avatarAlex Elder <elder@inktank.com>
Reviewed-by: default avatarJosh Durgin <josh.durgin@inktank.com>
parent c8d18425

Documentation/ABI/testing/sysfs-bus-rbd

+7 −0
Original line number Diff line number Diff line
@@ -25,6 +25,10 @@ client_id 


	The ceph unique client id that was assigned for this specific session.



features



	A hexadecimal encoding of the feature bits for this image.



major



	The block device major number.
@@ -78,4 +82,7 @@ snap_size 


	The size of the image when this snapshot was taken.



snap_features



	A hexadecimal encoding of the feature bits for this snapshot.

drivers/block/rbd.c

+41 −2
Original line number Diff line number Diff line
@@ -85,6 +85,7 @@ 
struct rbd_image_header {

	/* These four fields never change for a given rbd image */

	char *object_prefix;

	u64 features;

	__u8 obj_order;

	__u8 crypt_type;

	__u8 comp_type;
@@ -148,12 +149,14 @@ struct rbd_snap { 
	u64			size;

	struct list_head	node;

	u64			id;

	u64			features;

};



struct rbd_mapping {

	char                    *snap_name;

	u64                     snap_id;

	u64                     size;

	u64                     features;

	bool                    snap_exists;

	bool			read_only;

};
@@ -590,6 +593,7 @@ static int rbd_header_from_disk(struct rbd_image_header *header, 
		header->snap_sizes = NULL;

	}



	header->features = 0;	/* No features support in v1 images */

	header->obj_order = ondisk->options.order;

	header->crypt_type = ondisk->options.crypt_type;

	header->comp_type = ondisk->options.comp_type;
@@ -632,6 +636,7 @@ static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name) 
		if (!strcmp(snap_name, snap->name)) {

			rbd_dev->mapping.snap_id = snap->id;

			rbd_dev->mapping.size = snap->size;

			rbd_dev->mapping.features = snap->features;



			return 0;

		}
@@ -648,6 +653,7 @@ static int rbd_dev_set_mapping(struct rbd_device *rbd_dev, char *snap_name) 
		    sizeof (RBD_SNAP_HEAD_NAME))) {

		rbd_dev->mapping.snap_id = CEPH_NOSNAP;

		rbd_dev->mapping.size = rbd_dev->header.image_size;

		rbd_dev->mapping.features = rbd_dev->header.features;

		rbd_dev->mapping.snap_exists = false;

		rbd_dev->mapping.read_only = rbd_dev->rbd_opts.read_only;

		ret = 0;
@@ -1835,6 +1841,19 @@ static ssize_t rbd_size_show(struct device *dev, 
	return sprintf(buf, "%llu\n", (unsigned long long) size * SECTOR_SIZE);

}



/*

 * Note this shows the features for whatever's mapped, which is not

 * necessarily the base image.

 */

static ssize_t rbd_features_show(struct device *dev,

			     struct device_attribute *attr, char *buf)

{

	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);



	return sprintf(buf, "0x%016llx\n",

			(unsigned long long) rbd_dev->mapping.features);

}



static ssize_t rbd_major_show(struct device *dev,

			      struct device_attribute *attr, char *buf)

{
@@ -1884,6 +1903,10 @@ static ssize_t rbd_image_id_show(struct device *dev, 
	return sprintf(buf, "%s\n", rbd_dev->image_id);

}



/*

 * Shows the name of the currently-mapped snapshot (or

 * RBD_SNAP_HEAD_NAME for the base image).

 */

static ssize_t rbd_snap_show(struct device *dev,

			     struct device_attribute *attr,

			     char *buf)
@@ -1907,6 +1930,7 @@ static ssize_t rbd_image_refresh(struct device *dev, 
}



static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);

static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);

static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);

static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);

static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
@@ -1918,6 +1942,7 @@ static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); 


static struct attribute *rbd_attrs[] = {

	&dev_attr_size.attr,

	&dev_attr_features.attr,

	&dev_attr_major.attr,

	&dev_attr_client_id.attr,

	&dev_attr_pool.attr,
@@ -1971,12 +1996,24 @@ static ssize_t rbd_snap_id_show(struct device *dev, 
	return sprintf(buf, "%llu\n", (unsigned long long)snap->id);

}



static ssize_t rbd_snap_features_show(struct device *dev,

				struct device_attribute *attr,

				char *buf)

{

	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);



	return sprintf(buf, "0x%016llx\n",

			(unsigned long long) snap->features);

}



static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);

static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);

static DEVICE_ATTR(snap_features, S_IRUGO, rbd_snap_features_show, NULL);



static struct attribute *rbd_snap_attrs[] = {

	&dev_attr_snap_size.attr,

	&dev_attr_snap_id.attr,

	&dev_attr_snap_features.attr,

	NULL,

};
@@ -2037,7 +2074,8 @@ static int rbd_register_snap_dev(struct rbd_snap *snap, 


static struct rbd_snap *__rbd_add_snap_dev(struct rbd_device *rbd_dev,

						const char *snap_name,

						u64 snap_id, u64 snap_size)

						u64 snap_id, u64 snap_size,

						u64 snap_features)

{

	struct rbd_snap *snap;

	int ret;
@@ -2053,6 +2091,7 @@ static struct rbd_snap *__rbd_add_snap_dev(struct rbd_device *rbd_dev, 


	snap->id = snap_id;

	snap->size = snap_size;

	snap->features = snap_features;



	return snap;
@@ -2123,7 +2162,7 @@ static int rbd_dev_snaps_update(struct rbd_device *rbd_dev) 
			/* We haven't seen this snapshot before */



			new_snap = __rbd_add_snap_dev(rbd_dev, snap_name,

					snap_id, header->snap_sizes[index]);

					snap_id, header->snap_sizes[index], 0);

			if (IS_ERR(new_snap)) {

				int err = PTR_ERR(new_snap);

CRA Git | Maintained and supported by SUSTech CRA and CCSE