vdev_mirror_read
if (vdev->v_read == vdev_mirror_read) {
static int vdev_mirror_read(vdev_t *, const blkptr_t *, void *, off_t,
if (vd->v_read == vdev_mirror_read)
if (vd->v_read == vdev_mirror_read) {
vdev = vdev_create(guid, vdev_mirror_read);