Current File : //usr/src/vboxhost-6.0.14/vboxdrv/r0drv/linux/semfastmutex-r0drv-linux.c
/* $Id: semfastmutex-r0drv-linux.c 127855 2019-01-01 01:45:53Z bird $ */
/** @file
* IPRT - Fast Mutex Semaphores, Ring-0 Driver, Linux.
*/
/*
* Copyright (C) 2006-2019 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-linux-kernel.h"
#include "internal/iprt.h"
#include <iprt/semaphore.h>
#include <iprt/alloc.h>
#include <iprt/assert.h>
#include <iprt/asm.h>
#include <iprt/errcore.h>
#if defined(RT_STRICT) || defined(IPRT_DEBUG_SEMS)
# include <iprt/thread.h>
#endif
#include "internal/magics.h"
/*********************************************************************************************************************************
* Structures and Typedefs *
*********************************************************************************************************************************/
/**
* Wrapper for the linux semaphore structure.
*/
typedef struct RTSEMFASTMUTEXINTERNAL
{
/** Magic value (RTSEMFASTMUTEX_MAGIC). */
uint32_t u32Magic;
/** the linux semaphore. */
struct semaphore Semaphore;
#if defined(RT_STRICT) || defined(IPRT_DEBUG_SEMS)
/** For check. */
RTNATIVETHREAD volatile Owner;
#endif
} RTSEMFASTMUTEXINTERNAL, *PRTSEMFASTMUTEXINTERNAL;
RTDECL(int) RTSemFastMutexCreate(PRTSEMFASTMUTEX phFastMtx)
{
IPRT_LINUX_SAVE_EFL_AC();
/*
* Allocate.
*/
PRTSEMFASTMUTEXINTERNAL pThis;
pThis = (PRTSEMFASTMUTEXINTERNAL)RTMemAlloc(sizeof(*pThis));
if (!pThis)
return VERR_NO_MEMORY;
/*
* Initialize.
*/
pThis->u32Magic = RTSEMFASTMUTEX_MAGIC;
sema_init(&pThis->Semaphore, 1);
#if defined(RT_STRICT) || defined(IPRT_DEBUG_SEMS)
pThis->Owner = NIL_RTNATIVETHREAD;
#endif
*phFastMtx = pThis;
IPRT_LINUX_RESTORE_EFL_AC();
return VINF_SUCCESS;
}
RT_EXPORT_SYMBOL(RTSemFastMutexCreate);
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, ("u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), VERR_INVALID_HANDLE);
ASMAtomicWriteU32(&pThis->u32Magic, RTSEMFASTMUTEX_MAGIC_DEAD);
RTMemFree(pThis);
return VINF_SUCCESS;
}
RT_EXPORT_SYMBOL(RTSemFastMutexDestroy);
RTDECL(int) RTSemFastMutexRequest(RTSEMFASTMUTEX hFastMtx)
{
IPRT_LINUX_SAVE_EFL_AC();
/*
* Validate.
*/
PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), VERR_INVALID_HANDLE);
IPRT_DEBUG_SEMS_STATE(pThis, 'd');
down(&pThis->Semaphore);
#if defined(RT_STRICT) || defined(IPRT_DEBUG_SEMS)
IPRT_DEBUG_SEMS_STATE(pThis, 'o');
AssertRelease(pThis->Owner == NIL_RTNATIVETHREAD);
ASMAtomicUoWriteSize(&pThis->Owner, RTThreadNativeSelf());
#endif
IPRT_LINUX_RESTORE_EFL_ONLY_AC();
return VINF_SUCCESS;
}
RT_EXPORT_SYMBOL(RTSemFastMutexRequest);
RTDECL(int) RTSemFastMutexRelease(RTSEMFASTMUTEX hFastMtx)
{
IPRT_LINUX_SAVE_EFL_AC();
/*
* Validate.
*/
PRTSEMFASTMUTEXINTERNAL pThis = hFastMtx;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertMsgReturn(pThis->u32Magic == RTSEMFASTMUTEX_MAGIC, ("u32Magic=%RX32 pThis=%p\n", pThis->u32Magic, pThis), VERR_INVALID_HANDLE);
#if defined(RT_STRICT) || defined(IPRT_DEBUG_SEMS)
AssertRelease(pThis->Owner == RTThreadNativeSelf());
ASMAtomicUoWriteSize(&pThis->Owner, NIL_RTNATIVETHREAD);
#endif
up(&pThis->Semaphore);
IPRT_DEBUG_SEMS_STATE(pThis, 'u');
IPRT_LINUX_RESTORE_EFL_ONLY_AC();
return VINF_SUCCESS;
}
RT_EXPORT_SYMBOL(RTSemFastMutexRelease);
Mini Shell