+ * inputs:
+ * zc_name name of new filesystem or snapshot
+ * zc_value full name of old snapshot
+ *
+ * outputs:
+ * zc_cookie space in bytes
+ * zc_objset_type compressed space in bytes
+ * zc_perm_action uncompressed space in bytes
+ */
+static int
+zfs_ioc_space_written(zfs_cmd_t *zc)
+{
+ int error;
+ dsl_dataset_t *new, *old;
+
+ error = dsl_dataset_hold(zc->zc_name, FTAG, &new);
+ if (error != 0)
+ return (error);
+ error = dsl_dataset_hold(zc->zc_value, FTAG, &old);
+ if (error != 0) {
+ dsl_dataset_rele(new, FTAG);
+ return (error);
+ }
+
+ error = dsl_dataset_space_written(old, new, &zc->zc_cookie,
+ &zc->zc_objset_type, &zc->zc_perm_action);
+ dsl_dataset_rele(old, FTAG);
+ dsl_dataset_rele(new, FTAG);
+ return (error);
+}
+
+/*
+ * inputs:
+ * zc_name full name of last snapshot
+ * zc_value full name of first snapshot
+ *
+ * outputs:
+ * zc_cookie space in bytes
+ * zc_objset_type compressed space in bytes
+ * zc_perm_action uncompressed space in bytes
+ */
+static int
+zfs_ioc_space_snaps(zfs_cmd_t *zc)
+{
+ int error;
+ dsl_dataset_t *new, *old;
+
+ error = dsl_dataset_hold(zc->zc_name, FTAG, &new);
+ if (error != 0)
+ return (error);
+ error = dsl_dataset_hold(zc->zc_value, FTAG, &old);
+ if (error != 0) {
+ dsl_dataset_rele(new, FTAG);
+ return (error);
+ }
+
+ error = dsl_dataset_space_wouldfree(old, new, &zc->zc_cookie,
+ &zc->zc_objset_type, &zc->zc_perm_action);
+ dsl_dataset_rele(old, FTAG);
+ dsl_dataset_rele(new, FTAG);
+ return (error);
+}
+
+/*