diff options
| -rw-r--r-- | drivers/block/rbd.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index bce1fcfb5185..842caf4aab47 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -70,7 +70,10 @@ #define RBD_SNAP_HEAD_NAME "-" +/* This allows a single page to hold an image name sent by OSD */ +#define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1) #define RBD_IMAGE_ID_LEN_MAX 64 + #define RBD_OBJ_PREFIX_LEN_MAX 64 /* Feature bits */ @@ -658,6 +661,20 @@ out_err: return -ENOMEM; } +static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) +{ + struct rbd_snap *snap; + + if (snap_id == CEPH_NOSNAP) + return RBD_SNAP_HEAD_NAME; + + list_for_each_entry(snap, &rbd_dev->snaps, node) + if (snap_id == snap->id) + return snap->name; + + return NULL; +} + static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name) { @@ -2499,6 +2516,7 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) goto out_err; } parent_spec->image_id = image_id; + parent_spec->image_id_len = len; ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err); ceph_decode_64_safe(&p, end, overlap, out_err); @@ -2514,6 +2532,117 @@ out_err: return ret; } +static char *rbd_dev_image_name(struct rbd_device *rbd_dev) +{ + size_t image_id_size; + char *image_id; + void *p; + void *end; + size_t size; + void *reply_buf = NULL; + size_t len = 0; + char *image_name = NULL; + int ret; + + rbd_assert(!rbd_dev->spec->image_name); + + image_id_size = sizeof (__le32) + rbd_dev->spec->image_id_len; + image_id = kmalloc(image_id_size, GFP_KERNEL); + if (!image_id) + return NULL; + + p = image_id; + end = (char *) image_id + image_id_size; + ceph_encode_string(&p, end, rbd_dev->spec->image_id, + (u32) rbd_dev->spec->image_id_len); + + size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX; + reply_buf = kmalloc(size, GFP_KERNEL); + if (!reply_buf) + goto out; + + ret = rbd_req_sync_exec(rbd_dev, RBD_DIRECTORY, + "rbd", "dir_get_name", + image_id, image_id_size, + (char *) reply_buf, size, + CEPH_OSD_FLAG_READ, NULL); + if (ret < 0) + goto out; + p = reply_buf; + end = (char *) reply_buf + size; + image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); + if (IS_ERR(image_name)) + image_name = NULL; + else + dout("%s: name is %s len is %zd\n", __func__, image_name, len); +out: + kfree(reply_buf); + kfree(image_id); + + return image_name; +} + +/* + * When a parent image gets probed, we only have the pool, image, + * and snapshot ids but not the names of any of them. This call + * is made later to fill in those names. It has to be done after + * rbd_dev_snaps_update() has completed because some of the + * information (in particular, snapshot name) is not available + * until then. + */ +static int rbd_dev_probe_update_spec(struct rbd_device *rbd_dev) +{ + struct ceph_osd_client *osdc; + const char *name; + void *reply_buf = NULL; + int ret; + + if (rbd_dev->spec->pool_name) + return 0; /* Already have the names */ + + /* Look up the pool name */ + + osdc = &rbd_dev->rbd_client->client->osdc; + name = ceph_pg_pool_name_by_id(osdc->osdmap, rbd_dev->spec->pool_id); + if (!name) + return -EIO; /* pool id too large (>= 2^31) */ + + rbd_dev->spec->pool_name = kstrdup(name, GFP_KERNEL); + if (!rbd_dev->spec->pool_name) + return -ENOMEM; + + /* Fetch the image name; tolerate failure here */ + + name = rbd_dev_image_name(rbd_dev); + if (name) { + rbd_dev->spec->image_name_len = strlen(name); + rbd_dev->spec->image_name = (char *) name; + } else { + pr_warning(RBD_DRV_NAME "%d " + "unable to get image name for image id %s\n", + rbd_dev->major, rbd_dev->spec->image_id); + } + + /* Look up the snapshot name. */ + + name = rbd_snap_name(rbd_dev, rbd_dev->spec->snap_id); + if (!name) { + ret = -EIO; + goto out_err; + } + rbd_dev->spec->snap_name = kstrdup(name, GFP_KERNEL); + if(!rbd_dev->spec->snap_name) + goto out_err; + + return 0; +out_err: + kfree(reply_buf); + kfree(rbd_dev->spec->pool_name); + rbd_dev->spec->pool_name = NULL; + + return ret; +} + static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver) { size_t size; @@ -3372,6 +3501,10 @@ static int rbd_dev_probe_finish(struct rbd_device *rbd_dev) if (ret) return ret; + ret = rbd_dev_probe_update_spec(rbd_dev); + if (ret) + goto err_out_snaps; + ret = rbd_dev_set_mapping(rbd_dev); if (ret) goto err_out_snaps; |