-extern nvlist_t *vdev_label_read_config(vdev_t *vd);
-extern void vdev_uberblock_load(zio_t *zio, vdev_t *vd, struct uberblock *ub);
+extern nvlist_t *vdev_label_read_config(vdev_t *vd, uint64_t txg);
+extern void vdev_uberblock_load(vdev_t *, struct uberblock *, nvlist_t **);