diff --git a/VoldNativeService.h b/VoldNativeService.h
index e446185..d5de707 100644
--- a/VoldNativeService.h
+++ b/VoldNativeService.h
@@ -118,6 +118,9 @@
             int32_t userId, int32_t userSerial, int32_t flags);
     binder::Status destroyUserStorage(const std::unique_ptr<std::string>& uuid,
             int32_t userId, int32_t flags);
+
+    binder::Status mountExternalStorageForApp(const std::string& packageName, int32_t appId,
+            const std::string& sandboxId, int32_t userId);
 };
 
 }  // namespace vold