rtmemlocked-posix.cpp revision cb62273b023a1efb7864e02410a10fce430bc050
/* $Id$ */
/** @file
* IPRT - RTMemLocked*, POSIX.
*/
/*
* Copyright (C) 2014 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 "internal/iprt.h"
#include <iprt/mem.h>
#include <iprt/assert.h>
#include <iprt/err.h>
#include <iprt/param.h>
#include <iprt/string.h>
#include "internal/mem.h"
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/errno.h>
/*******************************************************************************
* Defined Constants And Macros *
*******************************************************************************/
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
/**
* Header for a locked memory region.
*/
typedef struct RTMEMLOCKEDHDR
{
/** Magic value. */
uint32_t u32Magic;
/** Size of the region in bytes including the header, rounded to a page aligned value. */
size_t cbRegion;
#if HC_ARCH_BITS == 64
/** 8 byte alignment of the structure on 64bit platforms. */
uint32_t u32Alignment;
#endif
} RTMEMLOCKEDHDR;
/** Pointer to a locked memory region header. */
typedef RTMEMLOCKEDHDR *PRTMEMLOCKEDHDR;
/** Magic for the header. (Vienna Teng) */
#define RTMEMLOCKEDHDR_MAGIC UINT32_C(0x19781003)
RTDECL(int) RTMemLockedAllocExTag(size_t cb, const char *pszTag, void **ppv) RT_NO_THROW
{
int rc = VINF_SUCCESS;
size_t cbAlloc = RT_ALIGN_Z(cb + sizeof(RTMEMLOCKEDHDR), PAGE_SIZE);
void *pv;
NOREF(pszTag);
pv = mmap(NULL, cbAlloc, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS,
-1, 0);
if (pv != MAP_FAILED)
{
int rcPosix = mlock(pv, cbAlloc);
if (!rcPosix)
{
PRTMEMLOCKEDHDR pHdr = (PRTMEMLOCKEDHDR)pv;
AssertPtr(pHdr);
pHdr->u32Magic = RTMEMLOCKEDHDR_MAGIC;
pHdr->cbRegion = cbAlloc;
*ppv = pHdr + 1;
}
else
rc = RTErrConvertFromErrno(errno);
}
return rc;
}
RTDECL(int) RTMemLockedAllocZExTag(size_t cb, const char *pszTag, void **ppv) RT_NO_THROW
{
void *pv = NULL;
int rc = RTMemLockedAllocExTag(cb, pszTag, &pv);
if (RT_SUCCESS(rc))
{
RT_BZERO(pv, cb);
*ppv = pv;
}
return rc;
}
RTDECL(void *) RTMemLockedAllocTag(size_t cb, const char *pszTag) RT_NO_THROW
{
void *pv = NULL;
int rc = RTMemLockedAllocExTag(cb, pszTag, &pv);
if (RT_FAILURE(rc))
return NULL;
return pv;
}
RTDECL(void *) RTMemLockedAllocZTag(size_t cb, const char *pszTag) RT_NO_THROW
{
void *pv = NULL;
int rc = RTMemLockedAllocZExTag(cb, pszTag, &pv);
if (RT_FAILURE(rc))
return NULL;
return pv;
}
RTDECL(void) RTMemLockedFree(void *pv) RT_NO_THROW
{
/*
* Validate & adjust the input.
*/
if (!pv)
return;
AssertPtr(pv);
int rcPosix;
PRTMEMLOCKEDHDR pHdr = ((PRTMEMLOCKEDHDR)pv) - 1;
AssertReturnVoid(pHdr->u32Magic == RTMEMLOCKEDHDR_MAGIC);
pHdr->u32Magic = ~RTMEMLOCKEDHDR_MAGIC;
rcPosix = munlock(pHdr, pHdr->cbRegion);
AssertMsg(rcPosix == 0, ("rc=%d errno=%d pv=%p\n", rcPosix, errno, pHdr)); NOREF(rcPosix);
rcPosix = munmap(pHdr, pHdr->cbRegion);
AssertMsg(rcPosix == 0, ("rc=%d errno=%d pv=%p\n", rcPosix, errno, pHdr)); NOREF(rcPosix);
}