It used to be an internal helper function just for implementing bdrv_co_do_readv/writev(), but now that it's a public interface, it deserves a name without "do" in it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>