This provides the lib/lvol wrapper around blobstore's external
snapshots. Later commits make this work with vbdev_lvol.
The blobstore external snapshot implementation stores an opaque
identifier in an internal xattr. Lvstore uses this to store the
stringified UUID of the bdev that will act as the external snapshot.
This is used by the newly introduced spdk_lvol_create_esnap_clone() to
store the bdev UUID in the blob's metadata.
Change-Id: I58c7b32b656ad1d21a446e3b91e59e655efac7e4
Signed-off-by: Mike Gerdts <mgerdts@nvidia.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/14977
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Community-CI: Mellanox Build Bot
609205739e