diff --git a/VolumeManager.h b/VolumeManager.h
index 943a144..2d6b968 100644
--- a/VolumeManager.h
+++ b/VolumeManager.h
@@ -242,4 +242,10 @@
     bool mSecureKeyguardShowing;
 };
 
+namespace android {
+namespace vold {
+android::status_t GetStorageSize(int64_t* storageSize);
+}
+}  // namespace android
+
 #endif