[libvirt] Why not add snapshot operations for Sheepdog storage driver in Libvirt

Hi all, Virsh has following operations about snapshot. Snapshot (help keyword 'snapshot') snapshot-create Create a snapshot from XML snapshot-create-as Create a snapshot from a set of args snapshot-current Get or set the current snapshot snapshot-delete Delete a domain snapshot snapshot-dumpxml Dump XML for a domain snapshot snapshot-edit edit XML for a snapshot snapshot-info snapshot information snapshot-list List snapshots for a domain snapshot-parent Get the name of the parent of a snapshot snapshot-revert Revert a domain to a snapshot But i cannot find relevant realization in Sheepdog storage driver in Libvirt. I am sure Sheepdog storage driver, now, cannot support snapshot operations in Libvirt. I wonder whether Sheepdog can realize snapshot operations in Libvirt? Maybe i can finish these jobs. I am not clear about how to let Sheepdog storage driver support snapshot operations. Could anyone give me some suggestions? Thanks in advance. -- Thanks Harry Wei