--- old/usr/src/uts/common/fs/zfs/vdev_raidz.c	Mon Apr  7 00:45:28 2008
+++ new/usr/src/uts/common/fs/zfs/vdev_raidz.c	Mon Apr  7 00:45:28 2008
@@ -1226,6 +1226,13 @@
 		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,
@@ -1234,6 +1241,7 @@
 	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 */
 };