We are gradually moving away from sector-based interfaces, towards
byte-based.  Update the generic helpers, and all passthrough clients
(blkdebug, commit, mirror, throttle) accordingly.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>