diff --git a/thin-provisioning/metadata_dumper.cc b/thin-provisioning/metadata_dumper.cc
index 5006fc0..9ba0614 100644
--- a/thin-provisioning/metadata_dumper.cc
+++ b/thin-provisioning/metadata_dumper.cc
@@ -244,3 +244,14 @@ thin_provisioning::metadata_dump(metadata::ptr md, emitter::ptr e, bool repair)
 }
 
 //----------------------------------------------------------------
+
+void
+thin_provisioning::metadata_dump_subtree(metadata::ptr md, emitter::ptr e, bool repair, uint64_t subtree_root) {
+	mapping_emitter me(e);
+	single_mapping_tree tree(*md->tm_, subtree_root,
+				 mapping_tree_detail::block_time_ref_counter(md->data_sm_));
+	walk_mapping_tree(tree, static_cast<mapping_tree_detail::mapping_visitor &>(me),
+			  *mapping_damage_policy(repair));
+}
+
+//----------------------------------------------------------------
diff --git a/thin-provisioning/metadata_dumper.h b/thin-provisioning/metadata_dumper.h
index c96d22e..007256a 100644
--- a/thin-provisioning/metadata_dumper.h
+++ b/thin-provisioning/metadata_dumper.h
@@ -29,6 +29,7 @@ namespace thin_provisioning {
 	// the dumper to do it's best to recover info.  If not set, any
 	// corruption encountered will cause an exception to be thrown.
 	void metadata_dump(metadata::ptr md, emitter::ptr e, bool repair);
+	void metadata_dump_subtree(metadata::ptr md, emitter::ptr e, bool repair, uint64_t subtree_root);
 }
 
 //----------------------------------------------------------------