vdev_get_min_asize
oldsize = vdev_get_min_asize(oldvd);
newsize = vdev_get_min_asize(newvd);
adddev->l2ad_end = VDEV_LABEL_START_SIZE + vdev_get_min_asize(vd);
if (newvd->vdev_asize < vdev_get_min_asize(oldvd))
extern uint64_t vdev_get_min_asize(vdev_t *vd);
vd->vdev_min_asize = vdev_get_min_asize(vd);
vd->vdev_min_asize = vdev_get_min_asize(vd);
vs->vs_rsize = vdev_get_min_asize(vd);