raw: Implement copy offloading

Just pass down to ->file.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20180601092648.24614-4-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
1 file changed