[PATCH v2 10/10] ntoskrnl.exe: Implement Ex(Acquire/Release)FastMutex.

[Derek Lesho]

Signed-off-by: Derek Lesho <dereklesho52 at Gmail.com>
---
 dlls/ntoskrnl.exe/ntoskrnl.c         |  1 +
 dlls/ntoskrnl.exe/ntoskrnl.exe.spec  |  2 ++
 dlls/ntoskrnl.exe/ntoskrnl_private.h |  1 +
 dlls/ntoskrnl.exe/sync.c             | 34 ++++++++++++++++++++++++++++
 include/ddk/wdm.h                    |  4 ++++
 5 files changed, 42 insertions(+)

diff --git a/dlls/ntoskrnl.exe/ntoskrnl.c b/dlls/ntoskrnl.exe/ntoskrnl.c
index 46fd243d75..32ead1ff20 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.c
+++ b/dlls/ntoskrnl.exe/ntoskrnl.c
@@ -2518,6 +2518,7 @@ static void *create_thread_object( HANDLE handle )
     ObDereferenceObject( thread->process );
 
     thread->critical_region = FALSE;
+    thread->irql = PASSIVE_LEVEL;
 
     return thread;
 }
diff --git a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
index 399258cdfd..f4e6d8f710 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
+++ b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
@@ -1,4 +1,5 @@
 @ stdcall -fastcall ExAcquireFastMutexUnsafe(ptr)
+@ stdcall ExAcquireFastMutex(ptr)
 @ stub ExAcquireRundownProtection
 @ stub ExAcquireRundownProtectionEx
 @ stub ExInitializeRundownProtection
@@ -9,6 +10,7 @@
 @ stdcall -fastcall -arch=i386 ExInterlockedPushEntrySList (ptr ptr ptr) NTOSKRNL_ExInterlockedPushEntrySList
 @ stub ExReInitializeRundownProtection
 @ stdcall -fastcall ExReleaseFastMutexUnsafe(ptr)
+@ stdcall ExReleaseFastMutex(ptr)
 @ stdcall ExReleaseResourceLite(ptr)
 @ stub ExReleaseRundownProtection
 @ stub ExReleaseRundownProtectionEx
diff --git a/dlls/ntoskrnl.exe/ntoskrnl_private.h b/dlls/ntoskrnl.exe/ntoskrnl_private.h
index 940ff526f9..84f8387262 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl_private.h
+++ b/dlls/ntoskrnl.exe/ntoskrnl_private.h
@@ -38,6 +38,7 @@ struct _KTHREAD
     CLIENT_ID id;
     PEPROCESS process;
     BOOLEAN critical_region;
+    UCHAR irql;
 };
 
 void *alloc_kernel_object( POBJECT_TYPE type, HANDLE handle, SIZE_T size, LONG ref ) DECLSPEC_HIDDEN;
diff --git a/dlls/ntoskrnl.exe/sync.c b/dlls/ntoskrnl.exe/sync.c
index bb2d318e56..15a602d3f4 100644
--- a/dlls/ntoskrnl.exe/sync.c
+++ b/dlls/ntoskrnl.exe/sync.c
@@ -689,3 +689,37 @@ void WINAPI ExReleaseFastMutexUnsafe( FAST_MUTEX *mutex )
     if (InterlockedIncrement(&mutex->Count) < 1)
         KeSetEvent( &mutex->Event, IO_NO_INCREMENT, FALSE );
 }
+
+
+/*********************************************************************
+ *           ExAcquireFastMutex    (NTOSKRNL.@)
+ */
+DEFINE_FASTCALL1_WRAPPER(ExAcquireFastMutex)
+void WINAPI ExAcquireFastMutex(PFAST_MUTEX mutex)
+{
+    KIRQL old_irql;
+    PKTHREAD thread = KeGetCurrentThread();
+
+    /* The safe variant raises thread to APC_LEVEL */
+    old_irql = thread->irql;
+    thread->irql = APC_LEVEL;
+
+    ExAcquireFastMutexUnsafe( mutex );
+
+    mutex->OldIrql = old_irql;
+}
+
+
+ /*********************************************************************
+ *           ExReleaseFastMutex    (NTOSKRNL.@)
+ */
+DEFINE_FASTCALL1_WRAPPER(ExReleaseFastMutex)
+void WINAPI ExReleaseFastMutex(PFAST_MUTEX mutex)
+{
+    KIRQL old_irql = mutex->OldIrql;
+    PKTHREAD thread = mutex->Owner;
+
+    ExReleaseFastMutexUnsafe( mutex );
+
+    thread->irql = old_irql;
+}
diff --git a/include/ddk/wdm.h b/include/ddk/wdm.h
index 02c1bf3f20..3611c7cd90 100644
--- a/include/ddk/wdm.h
+++ b/include/ddk/wdm.h
@@ -168,6 +168,10 @@ typedef struct _LOOKASIDE_LIST_EX *PLOOKASIDE_LIST_EX;
 
 #define FM_LOCK_BIT 0x1
 
+/* irqls */
+#define PASSIVE_LEVEL 0
+#define APC_LEVEL     1
+
 typedef struct _FAST_MUTEX
 {
     LONG Count;
-- 
2.20.1