diff --git a/reactos/include/ddk/wdm.h b/reactos/include/ddk/wdm.h
index b658c77faa3..b21aac4f80f 100644
--- a/reactos/include/ddk/wdm.h
+++ b/reactos/include/ddk/wdm.h
@@ -2463,6 +2463,18 @@ FASTCALL
 ExTryToAcquireFastMutex(
     IN OUT PFAST_MUTEX FastMutex);
 
+NTKERNELAPI
+VOID
+FASTCALL
+ExAcquireFastMutexUnsafe(
+    IN OUT PFAST_MUTEX FastMutex);
+
+NTKERNELAPI
+VOID
+FASTCALL
+ExReleaseFastMutexUnsafe(
+    IN OUT PFAST_MUTEX FastMutex);
+
 NTKERNELAPI
 BOOLEAN
 NTAPI