diff --git a/VoldNativeService.h b/VoldNativeService.h
index d0c31e8..40ce3a4 100644
--- a/VoldNativeService.h
+++ b/VoldNativeService.h
@@ -111,6 +111,9 @@ class VoldNativeService : public BinderService<VoldNativeService>, public os::Bn
     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);
+
     binder::Status startCheckpoint(int32_t retry);
     binder::Status needsCheckpoint(bool* _aidl_return);
     binder::Status needsRollback(bool* _aidl_return);