[PATCH v8 0/2] MR2044: ntoskrnl.exe: Implement acquiring and releasing guarded mutexes

[Etaash Mathamsetty (＠etaash.mathamsetty)]

according to MSDN they are implemented in the same way as a fast mutex.

--
  v8: ntoskrnl.exe: Implement KeReleaseGuardedMutex.
      ntoskrnl.exe: Implement KeAcquireGuardedMutex.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/2044

[PATCH v8 1/2] ntoskrnl.exe: Implement KeAcquireGuardedMutex.

[Etaash Mathamsetty]

From: Etaash Mathamsetty <[e-mail]>

---
 dlls/ntoskrnl.exe/ntoskrnl.exe.spec |  2 ++
 dlls/ntoskrnl.exe/sync.c            | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
index 4426e5066e0..cea2538c719 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
+++ b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
@@ -52,6 +52,8 @@
 @ stdcall -fastcall IofCompleteRequest(ptr long)
 @ stdcall -arch=!i386 KeAcquireInStackQueuedSpinLock(ptr ptr)
 @ stdcall -fastcall KeAcquireInStackQueuedSpinLockAtDpcLevel(ptr ptr)
+@ stdcall KeAcquireGuardedMutexUnsafe(ptr)
+@ stdcall KeAcquireGuardedMutex(ptr)
 @ stdcall KeEnterGuardedRegion()
 @ stdcall KeExpandKernelStackAndCallout(ptr ptr long)
 @ stdcall KeExpandKernelStackAndCalloutEx(ptr ptr long long ptr)
diff --git a/dlls/ntoskrnl.exe/sync.c b/dlls/ntoskrnl.exe/sync.c
index 2183df351b2..773c241a17e 100644
--- a/dlls/ntoskrnl.exe/sync.c
+++ b/dlls/ntoskrnl.exe/sync.c
@@ -438,6 +438,29 @@ void WINAPI KeInitializeGuardedMutex(PKGUARDED_MUTEX mutex)
     KeInitializeEvent(&mutex->Event, SynchronizationEvent, FALSE);
 }
 
+/***********************************************************************
+ *           KeAcquireGuardedMutexUnsafe   (NTOSKRNL.EXE.@)
+ */
+void WINAPI KeAcquireGuardedMutexUnsafe(PKGUARDED_MUTEX mutex)
+{
+    LONG count; 
+
+    TRACE("mutex %p.\n", mutex);
+
+    count = InterlockedDecrement( &mutex->Count );
+    if (count < 0)
+        KeWaitForSingleObject( &mutex->Event, Executive, KernelMode, FALSE, NULL );
+}
+
+/***********************************************************************
+ *           KeAcquireGuardedMutex   (NTOSKRNL.EXE.@)
+ */
+void WINAPI KeAcquireGuardedMutex(PKGUARDED_MUTEX mutex)
+{
+    /* FIXME: Enter Guarded Region */
+    KeAcquireGuardedMutexUnsafe(mutex);
+}
+
 static void CALLBACK ke_timer_complete_proc(PTP_CALLBACK_INSTANCE instance, void *timer_, PTP_TIMER tp_timer)
 {
     KTIMER *timer = timer_;
-- 
GitLab


https://gitlab.winehq.org/wine/wine/-/merge_requests/2044

[PATCH v8 2/2] ntoskrnl.exe: Implement KeReleaseGuardedMutex.

[Etaash Mathamsetty]

From: Etaash Mathamsetty <[e-mail]>

---
 dlls/ntoskrnl.exe/ntoskrnl.exe.spec |  2 ++
 dlls/ntoskrnl.exe/sync.c            | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
index cea2538c719..70999698499 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
+++ b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
@@ -60,6 +60,8 @@
 @ stdcall KeLeaveGuardedRegion()
 @ stdcall -arch=!i386 KeReleaseInStackQueuedSpinLock(ptr)
 @ stdcall -fastcall KeReleaseInStackQueuedSpinLockFromDpcLevel(ptr)
+@ stdcall KeReleaseGuardedMutexUnsafe(ptr)
+@ stdcall KeReleaseGuardedMutex(ptr)
 @ stub KeSetTimeUpdateNotifyRoutine
 @ stub KefAcquireSpinLockAtDpcLevel
 @ stub KefReleaseSpinLockFromDpcLevel
diff --git a/dlls/ntoskrnl.exe/sync.c b/dlls/ntoskrnl.exe/sync.c
index 773c241a17e..ea97c0deead 100644
--- a/dlls/ntoskrnl.exe/sync.c
+++ b/dlls/ntoskrnl.exe/sync.c
@@ -461,6 +461,29 @@ void WINAPI KeAcquireGuardedMutex(PKGUARDED_MUTEX mutex)
     KeAcquireGuardedMutexUnsafe(mutex);
 }
 
+/***********************************************************************
+ *           KeReleaseGuardedMutexUnsafe   (NTOSKRNL.EXE.@)
+ */
+void WINAPI KeReleaseGuardedMutexUnsafe(PKGUARDED_MUTEX mutex)
+{
+    LONG count;
+
+    TRACE("mutex %p.\n", mutex);
+
+    count = InterlockedIncrement( &mutex->Count );
+    if (count < 1)
+        KeSetEvent( &mutex->Event, IO_NO_INCREMENT, FALSE );
+}
+
+/***********************************************************************
+ *           KeReleaseGuardedMutex   (NTOSKRNL.EXE.@)
+ */
+void WINAPI KeReleaseGuardedMutex(PKGUARDED_MUTEX mutex)
+{
+    KeReleaseGuardedMutexUnsafe(mutex);
+    /* FIXME: Leave Guarded Region */
+}
+
 static void CALLBACK ke_timer_complete_proc(PTP_CALLBACK_INSTANCE instance, void *timer_, PTP_TIMER tp_timer)
 {
     KTIMER *timer = timer_;
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/2044

[Etaash Mathamsetty (＠etaash.mathamsetty)]

On Wed Jan 28 07:10:25 2026 +0000, Etaash Mathamsetty wrote:
> Both unsafe and safe versions are fastcall? in wine the fast lock (safe
> version) is winapi (stdcall) for safe and fastcall for unsafe
> also what about KeInitializeGuardedMutex?

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/2044#note_128233