Format 2 objects use 16 characters for the object name suffix to be able to express the full 64-bit range of object numbers. Format 1 images only use 12 characters for this. Using 12-character names for format 2 caused userspace and kernel rbd clients to read differently named objects, which made an image written by one client look empty to the other client.
Reported-by: Chris Dunlop <[email protected]> Signed-off-by: Josh Durgin <[email protected]> --- drivers/block/rbd.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 9f72125..39ee017 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1028,12 +1028,16 @@ static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset) char *name; u64 segment; int ret; + char *name_format; name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO); if (!name) return NULL; segment = offset >> rbd_dev->header.obj_order; - ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx", + name_format = "%s.%012llx"; + if (rbd_dev->image_format == 2) + name_format = "%s.%016llx"; + ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, name_format, rbd_dev->header.object_prefix, segment); if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) { pr_err("error formatting segment name for #%llu (%d)\n", -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
