From b8b1e2db52de61f575981d0c23da785a7c5b4a77 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Tue, 3 Jul 2012 16:01:19 -0500 Subject: [PATCH] rbd: get snapshot name for a v2 image Define rbd_dev_v2_snap_name() to fetch the name for a particular snapshot in a format 2 rbd image. Define rbd_dev_v2_snap_info() to to be a wrapper for getting the name, size, and features for a particular snapshot, using an interface that matches the equivalent function for version 1 images. Define rbd_dev_snap_info() wrapper function and use it to call the appropriate function for getting the snapshot name, size, and features, dependent on the rbd image format. Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- drivers/block/rbd.c | 81 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 79 insertions(+), 2 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index b673a8dc161d..b51f1c997c1d 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -2319,6 +2319,83 @@ out: return 0; } +static char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, u32 which) +{ + size_t size; + void *reply_buf; + __le64 snap_id; + int ret; + void *p; + void *end; + size_t snap_name_len; + char *snap_name; + + size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN; + reply_buf = kmalloc(size, GFP_KERNEL); + if (!reply_buf) + return ERR_PTR(-ENOMEM); + + snap_id = cpu_to_le64(rbd_dev->header.snapc->snaps[which]); + ret = rbd_req_sync_exec(rbd_dev, rbd_dev->header_name, + "rbd", "get_snapshot_name", + (char *) &snap_id, sizeof (snap_id), + reply_buf, size, + CEPH_OSD_FLAG_READ, NULL); + dout("%s: rbd_req_sync_exec returned %d\n", __func__, ret); + if (ret < 0) + goto out; + + p = reply_buf; + end = (char *) reply_buf + size; + snap_name_len = 0; + snap_name = ceph_extract_encoded_string(&p, end, &snap_name_len, + GFP_KERNEL); + if (IS_ERR(snap_name)) { + ret = PTR_ERR(snap_name); + goto out; + } else { + dout(" snap_id 0x%016llx snap_name = %s\n", + (unsigned long long) le64_to_cpu(snap_id), snap_name); + } + kfree(reply_buf); + + return snap_name; +out: + kfree(reply_buf); + + return ERR_PTR(ret); +} + +static char *rbd_dev_v2_snap_info(struct rbd_device *rbd_dev, u32 which, + u64 *snap_size, u64 *snap_features) +{ + __le64 snap_id; + u8 order; + int ret; + + snap_id = rbd_dev->header.snapc->snaps[which]; + ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, &order, snap_size); + if (ret) + return ERR_PTR(ret); + ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, snap_features); + if (ret) + return ERR_PTR(ret); + + return rbd_dev_v2_snap_name(rbd_dev, which); +} + +static char *rbd_dev_snap_info(struct rbd_device *rbd_dev, u32 which, + u64 *snap_size, u64 *snap_features) +{ + if (rbd_dev->image_format == 1) + return rbd_dev_v1_snap_info(rbd_dev, which, + snap_size, snap_features); + if (rbd_dev->image_format == 2) + return rbd_dev_v2_snap_info(rbd_dev, which, + snap_size, snap_features); + return ERR_PTR(-EINVAL); +} + /* * Scan the rbd device's current snapshot list and compare it to the * newly-received snapshot context. Remove any existing snapshots @@ -2372,8 +2449,8 @@ static int rbd_dev_snaps_update(struct rbd_device *rbd_dev) continue; } - snap_name = rbd_dev_v1_snap_info(rbd_dev, index, - &snap_size, &snap_features); + snap_name = rbd_dev_snap_info(rbd_dev, index, + &snap_size, &snap_features); if (IS_ERR(snap_name)) return PTR_ERR(snap_name); -- 2.39.5