diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-rbd | 4 | ||||
| -rw-r--r-- | drivers/block/rbd.c | 131 | ||||
| -rw-r--r-- | include/linux/ceph/rados.h | 2 |
3 files changed, 137 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-rbd b/Documentation/ABI/testing/sysfs-bus-rbd index 1cf2adf46b11..cd9213ccf3dc 100644 --- a/Documentation/ABI/testing/sysfs-bus-rbd +++ b/Documentation/ABI/testing/sysfs-bus-rbd @@ -70,6 +70,10 @@ snap_* A directory per each snapshot +parent + + Information identifying the pool, image, and snapshot id for + the parent image in a layered rbd image (format 2 only). Entries under /sys/bus/rbd/devices/<dev-id>/snap_<snap-name> ------------------------------------------------------------- diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 28052ff679ca..bce1fcfb5185 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -217,6 +217,9 @@ struct rbd_device { struct ceph_osd_event *watch_event; struct ceph_osd_request *watch_request; + struct rbd_spec *parent_spec; + u64 parent_overlap; + /* protects updating the header */ struct rw_semaphore header_rwsem; @@ -2009,6 +2012,49 @@ static ssize_t rbd_snap_show(struct device *dev, return sprintf(buf, "%s\n", rbd_dev->spec->snap_name); } +/* + * For an rbd v2 image, shows the pool id, image id, and snapshot id + * for the parent image. If there is no parent, simply shows + * "(no parent image)". + */ +static ssize_t rbd_parent_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); + struct rbd_spec *spec = rbd_dev->parent_spec; + int count; + char *bufp = buf; + + if (!spec) + return sprintf(buf, "(no parent image)\n"); + + count = sprintf(bufp, "pool_id %llu\npool_name %s\n", + (unsigned long long) spec->pool_id, spec->pool_name); + if (count < 0) + return count; + bufp += count; + + count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id, + spec->image_name ? spec->image_name : "(unknown)"); + if (count < 0) + return count; + bufp += count; + + count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n", + (unsigned long long) spec->snap_id, spec->snap_name); + if (count < 0) + return count; + bufp += count; + + count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap); + if (count < 0) + return count; + bufp += count; + + return (ssize_t) (bufp - buf); +} + static ssize_t rbd_image_refresh(struct device *dev, struct device_attribute *attr, const char *buf, @@ -2032,6 +2078,7 @@ static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL); static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL); static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh); static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); +static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL); static struct attribute *rbd_attrs[] = { &dev_attr_size.attr, @@ -2043,6 +2090,7 @@ static struct attribute *rbd_attrs[] = { &dev_attr_name.attr, &dev_attr_image_id.attr, &dev_attr_current_snap.attr, + &dev_attr_parent.attr, &dev_attr_refresh.attr, NULL }; @@ -2192,6 +2240,7 @@ struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, static void rbd_dev_destroy(struct rbd_device *rbd_dev) { + rbd_spec_put(rbd_dev->parent_spec); kfree(rbd_dev->header_name); rbd_put_client(rbd_dev->rbd_client); rbd_spec_put(rbd_dev->spec); @@ -2400,6 +2449,71 @@ static int rbd_dev_v2_features(struct rbd_device *rbd_dev) &rbd_dev->header.features); } +static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) +{ + struct rbd_spec *parent_spec; + size_t size; + void *reply_buf = NULL; + __le64 snapid; + void *p; + void *end; + char *image_id; + u64 overlap; + size_t len = 0; + int ret; + + parent_spec = rbd_spec_alloc(); + if (!parent_spec) + return -ENOMEM; + + size = sizeof (__le64) + /* pool_id */ + sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */ + sizeof (__le64) + /* snap_id */ + sizeof (__le64); /* overlap */ + reply_buf = kmalloc(size, GFP_KERNEL); + if (!reply_buf) { + ret = -ENOMEM; + goto out_err; + } + + snapid = cpu_to_le64(CEPH_NOSNAP); + ret = rbd_req_sync_exec(rbd_dev, rbd_dev->header_name, + "rbd", "get_parent", + (char *) &snapid, sizeof (snapid), + (char *) reply_buf, size, + CEPH_OSD_FLAG_READ, NULL); + dout("%s: rbd_req_sync_exec returned %d\n", __func__, ret); + if (ret < 0) + goto out_err; + + ret = -ERANGE; + p = reply_buf; + end = (char *) reply_buf + size; + ceph_decode_64_safe(&p, end, parent_spec->pool_id, out_err); + if (parent_spec->pool_id == CEPH_NOPOOL) + goto out; /* No parent? No problem. */ + + image_id = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); + if (IS_ERR(image_id)) { + ret = PTR_ERR(image_id); + goto out_err; + } + parent_spec->image_id = image_id; + ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err); + ceph_decode_64_safe(&p, end, overlap, out_err); + + rbd_dev->parent_overlap = overlap; + rbd_dev->parent_spec = parent_spec; + parent_spec = NULL; /* rbd_dev now owns this */ +out: + ret = 0; +out_err: + kfree(reply_buf); + rbd_spec_put(parent_spec); + + return ret; +} + static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver) { size_t size; @@ -3154,6 +3268,12 @@ static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) ret = rbd_read_header(rbd_dev, &rbd_dev->header); if (ret < 0) goto out_err; + + /* Version 1 images have no parent (no layering) */ + + rbd_dev->parent_spec = NULL; + rbd_dev->parent_overlap = 0; + rbd_dev->image_format = 1; dout("discovered version 1 image, header name is %s\n", @@ -3205,6 +3325,14 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) if (ret < 0) goto out_err; + /* If the image supports layering, get the parent info */ + + if (rbd_dev->header.features & RBD_FEATURE_LAYERING) { + ret = rbd_dev_v2_parent_info(rbd_dev); + if (ret < 0) + goto out_err; + } + /* crypto and compression type aren't (yet) supported for v2 images */ rbd_dev->header.crypt_type = 0; @@ -3224,6 +3352,9 @@ static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) return 0; out_err: + rbd_dev->parent_overlap = 0; + rbd_spec_put(rbd_dev->parent_spec); + rbd_dev->parent_spec = NULL; kfree(rbd_dev->header_name); rbd_dev->header_name = NULL; kfree(rbd_dev->header.object_prefix); diff --git a/include/linux/ceph/rados.h b/include/linux/ceph/rados.h index 0a99099801a4..15077db662ed 100644 --- a/include/linux/ceph/rados.h +++ b/include/linux/ceph/rados.h @@ -87,6 +87,8 @@ struct ceph_pg { * * lpgp_num -- as above. */ +#define CEPH_NOPOOL ((__u64) (-1)) /* pool id not defined */ + #define CEPH_PG_TYPE_REP 1 #define CEPH_PG_TYPE_RAID4 2 #define CEPH_PG_POOL_VERSION 2 |