vdev_find
top_vdev = vdev_find(&spa->spa_root_vdev->v_children, top_guid);
vdev = vdev_find(&root->v_children, top_guid);
vdev = vdev_find(&root->v_children, guid);
vdev = vdev_find(&spa->spa_root_vdev->v_children, guid);
(vdev_find(&top->v_children, guid) != NULL);
vdev = vdev_find(&spa->spa_root_vdev->v_children, guid);
vdev = vdev_find(&spa->spa_root_vdev->v_children, guid);
if ((vdev = vdev_find(&vdev->v_children, guid)) != NULL)
if ((vdev = vdev_find(&orphans, guid))) {