+/*
+ * Generate a view of the top-level vdevs. If we currently have holes
+ * in the namespace, then generate an array which contains a list of holey
+ * vdevs. Additionally, add the number of top-level children that currently
+ * exist.
+ */
+void
+vdev_top_config_generate(spa_t *spa, nvlist_t *config)
+{
+ vdev_t *rvd = spa->spa_root_vdev;
+ uint64_t *array;
+ uint_t c, idx;
+
+ array = kmem_alloc(rvd->vdev_children * sizeof (uint64_t), KM_SLEEP);
+
+ for (c = 0, idx = 0; c < rvd->vdev_children; c++) {
+ vdev_t *tvd = rvd->vdev_child[c];
+
+ if (tvd->vdev_ishole)
+ array[idx++] = c;
+ }
+
+ if (idx) {
+ VERIFY(nvlist_add_uint64_array(config, ZPOOL_CONFIG_HOLE_ARRAY,
+ array, idx) == 0);
+ }
+
+ VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VDEV_CHILDREN,
+ rvd->vdev_children) == 0);
+
+ kmem_free(array, rvd->vdev_children * sizeof (uint64_t));
+}
+