1 files changed, 138 insertions, 0 deletions
diff --git a/src/VBox/Runtime/r0drv/nt/semfastmutex-r0drv-nt.cpp b/src/VBox/Runtime/r0drv/nt/semfastmutex-r0drv-nt.cpp
new file mode 100644
index 00000000..0780a2dd
--- /dev/null
+++ b/src/VBox/Runtime/r0drv/nt/semfastmutex-r0drv-nt.cpp
@@ -0,0 +1,138 @@
+/* $Id: semfastmutex-r0drv-nt.cpp $ */
+/** @file
+ * IPRT - Fast Mutex Semaphores, Ring-0 Driver, NT.
+ */
+
+/*
+ * Copyright (C) 2006-2020 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include "the-nt-kernel.h"
+#include <iprt/semaphore.h>
+#include <iprt/alloc.h>
+#include <iprt/assert.h>
+#include <iprt/asm.h>
+#include <iprt/errcore.h>
+
+#include "internal/magics.h"
+
+
+/*********************************************************************************************************************************
+*   Structures and Typedefs                                                                                                      *
+*********************************************************************************************************************************/
+/**
+ * Wrapper for the linux semaphore structure.
+ */
+typedef struct RTSEMFASTMUTEXINTERNAL
+{
+    /** Magic value (RTSEMFASTMUTEX_MAGIC). */
+    uint32_t            u32Magic;
+    /** the NT fast mutex. */
+    FAST_MUTEX          Mutex;
+} RTSEMFASTMUTEXINTERNAL, *PRTSEMFASTMUTEXINTERNAL;
+
+
+
+RTDECL(int)  RTSemFastMutexCreate(PRTSEMFASTMUTEX phFastMtx)
+{
+    /*
+     * Allocate.
+     */
+    PRTSEMFASTMUTEXINTERNAL pThis;
+    Assert(sizeof(*pThis) > sizeof(void *));
+    pThis = (PRTSEMFASTMUTEXINTERNAL)RTMemAlloc(sizeof(*pThis));
+    if (!pThis)
+        return VERR_NO_MEMORY;
+
+    /*
+     * Initialize.
+     */
+    pThis->u32Magic = RTSEMFASTMUTEX_MAGIC;
+    ExInitializeFastMutex(&pThis->Mutex);
+
+    *phFastMtx = pThis;
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int)  RTSemFastMutexDestroy(RTSEMFASTMUTEX hFastMtx)
+{
+    /*
+     * Validate.
+     */
+    PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
+    if (pThis == NIL_RTSEMFASTMUTEX)
+        return VINF_SUCCESS;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("%p: u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);
+
+    ASMAtomicWriteU32(&pThis->u32Magic, RTSEMFASTMUTEX_MAGIC_DEAD);
+    Assert(pThis->Mutex.Count == 1);
+    RTMemFree(pThis);
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int)  RTSemFastMutexRequest(RTSEMFASTMUTEX hFastMtx)
+{
+    /*
+     * Validate.
+     */
+    PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("%p: u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);
+
+#if 1
+    /*
+     * ExAcquireFastMutex will set the IRQL to APC regardless of our current
+     * level.  Lowering the IRQL may screw things up, so do not allow this.
+     */
+# if 0 /** @todo enable this when the logger has been fixed. */
+    AssertMsg(KeGetCurrentIrql() <= APC_LEVEL, ("%d\n", KeGetCurrentIrql()), VERR_INVALID_STATE);
+# else  /* the gentler approach. */
+    KIRQL Irql = KeGetCurrentIrql();
+    if (Irql > APC_LEVEL)
+        return VERR_INVALID_STATE;
+# endif
+#endif
+
+    ExAcquireFastMutex(&pThis->Mutex);
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int)  RTSemFastMutexRelease(RTSEMFASTMUTEX hFastMtx)
+{
+    /*
+     * Validate.
+     */
+    PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
+    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
+    AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("%p: u32Magic=%RX32\n", pThis, pThis->u32Magic), VERR_INVALID_HANDLE);
+
+    ExReleaseFastMutex(&pThis->Mutex);
+    return VINF_SUCCESS;
+}
+