expandable RAID-Z

@@ -1224,16 +1224,24 @@
                 vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE);
         else
                 vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE);
 }
 
+static uint8_t
+vdev_raidz_grid(vdev_t *vd)
+{
+        ASSERT(vd->vdev_nparity - 1 <= 1);
+        return (((vd->vdev_nparity - 1) << 6) | vd->vdev_children);
+}
+
 vdev_ops_t vdev_raidz_ops = {
         vdev_raidz_open,
         vdev_raidz_close,
         NULL,
         vdev_raidz_asize,
         vdev_raidz_io_start,
         vdev_raidz_io_done,
         vdev_raidz_state_change,
+        vdev_raidz_grid,
         VDEV_TYPE_RAIDZ,        /* name of this vdev type */
         B_FALSE                 /* not a leaf vdev */
 };