diff --git a/binder/android/os/IVold.aidl b/binder/android/os/IVold.aidl
index de381d3..19ce9ba 100644
--- a/binder/android/os/IVold.aidl
+++ b/binder/android/os/IVold.aidl
@@ -54,6 +54,7 @@
 
     void remountUid(int uid, int remountMode);
     void remountAppStorageDirs(int uid, int pid, in @utf8InCpp String[] packageNames);
+    void unmountAppStorageDirs(int uid, int pid, in @utf8InCpp String[] packageNames);
 
     void setupAppDir(@utf8InCpp String path, int appUid);
     void fixupAppDir(@utf8InCpp String path, int appUid);