diff --git a/thin-provisioning/thin_delta.cc b/thin-provisioning/thin_delta.cc
index c12c084..ed32763 100644
--- a/thin-provisioning/thin_delta.cc
+++ b/thin-provisioning/thin_delta.cc
@@ -117,10 +117,10 @@ namespace {
if (oend_ - obegin_ > 1) {
cout << "" << endl;
+ << " length=\"" << oend_ - obegin_ << "\"/>" << '\n';
} else {
cout << "" << endl;
+ << " data_block=\"" << dbegin_ << "\"/>" << '\n';
}
obegin_ = oblock;