semfastmutex-r0drv-nt.cpp revision 7a99c98125959dcc22e09cf74a744ccf37c0e55b
/* $Id$ */
/** @file
* IPRT - Fast Mutex Semaphores, Ring-0 Driver, NT.
*/
/*
* Copyright (C) 2006-2007 Sun Microsystems, Inc.
*
* 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.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 USA or visit http://www.sun.com if you need
* additional information or have any questions.
*/
/*******************************************************************************
* 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/err.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 pMutexSem)
{
/*
* Allocate.
*/
PRTSEMFASTMUTEXINTERNAL pFastInt;
Assert(sizeof(*pFastInt) > sizeof(void *));
pFastInt = (PRTSEMFASTMUTEXINTERNAL)RTMemAlloc(sizeof(*pFastInt));
if (!pFastInt)
return VERR_NO_MEMORY;
/*
* Initialize.
*/
pFastInt->u32Magic = RTSEMFASTMUTEX_MAGIC;
ExInitializeFastMutex(&pFastInt->Mutex);
*pMutexSem = pFastInt;
return VINF_SUCCESS;
}
RTDECL(int) RTSemFastMutexDestroy(RTSEMFASTMUTEX MutexSem)
{
/*
* Validate.
*/
PRTSEMFASTMUTEXINTERNAL pFastInt = (PRTSEMFASTMUTEXINTERNAL)MutexSem;
if (!pFastInt)
return VERR_INVALID_PARAMETER;
if (pFastInt->u32Magic != RTSEMFASTMUTEX_MAGIC)
{
AssertMsgFailed(("pFastInt->u32Magic=%RX32 pMutexInt=%p\n", pFastInt->u32Magic, pFastInt));
return VERR_INVALID_PARAMETER;
}
ASMAtomicIncU32(&pFastInt->u32Magic);
Assert(pFastInt->Mutex.Count == 1);
/* It's not very clear what this Contention field really means. Seems to be a counter for the number of times contention occurred. (see e.g. http://winprogger.com/?p=6)
* The following assertion is therefor wrong:
* Assert(pFastInt->Mutex.Contention == 0);
*/
RTMemFree(pFastInt);
return VINF_SUCCESS;
}
RTDECL(int) RTSemFastMutexRequest(RTSEMFASTMUTEX MutexSem)
{
/*
* Validate.
*/
PRTSEMFASTMUTEXINTERNAL pFastInt = (PRTSEMFASTMUTEXINTERNAL)MutexSem;
if ( !pFastInt
|| pFastInt->u32Magic != RTSEMFASTMUTEX_MAGIC)
{
AssertMsgFailed(("pFastInt->u32Magic=%RX32 pMutexInt=%p\n", pFastInt ? pFastInt->u32Magic : 0, pFastInt));
return VERR_INVALID_PARAMETER;
}
#if 1
/*
* ExAcquireFastMutex will set the IRQL to APC regardless of our current
* level. Lowering the IRQL may screw things up, so to 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(&pFastInt->Mutex);
return VINF_SUCCESS;
}
RTDECL(int) RTSemFastMutexRelease(RTSEMFASTMUTEX MutexSem)
{
/*
* Validate.
*/
PRTSEMFASTMUTEXINTERNAL pFastInt = (PRTSEMFASTMUTEXINTERNAL)MutexSem;
if ( !pFastInt
|| pFastInt->u32Magic != RTSEMFASTMUTEX_MAGIC)
{
AssertMsgFailed(("pFastInt->u32Magic=%RX32 pMutexInt=%p\n", pFastInt ? pFastInt->u32Magic : 0, pFastInt));
return VERR_INVALID_PARAMETER;
}
ExReleaseFastMutex(&pFastInt->Mutex);
return VINF_SUCCESS;
}