/* $Id: alloc-r0drv.cpp 14743 2008-11-27 21:17:06Z vboxsync $ */ /** @file * IPRT - Memory Allocation, Ring-0 Driver. */ /* * 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 #include #include #include #include "r0drv/alloc-r0drv.h" /******************************************************************************* * Defined Constants And Macros * *******************************************************************************/ #ifdef RT_STRICT # define RTR0MEM_STRICT #endif #ifdef RTR0MEM_STRICT # define RTR0MEM_FENCE_EXTRA 16 #else # define RTR0MEM_FENCE_EXTRA 0 #endif /******************************************************************************* * Global Variables * *******************************************************************************/ #ifdef RTR0MEM_STRICT /** Fence data. */ static uint8_t const g_abFence[RTR0MEM_FENCE_EXTRA] = { 0x77, 0x88, 0x66, 0x99, 0x55, 0xaa, 0x44, 0xbb, 0x33, 0xcc, 0x22, 0xdd, 0x11, 0xee, 0x00, 0xff }; #endif /** * Allocates temporary memory. * * Temporary memory blocks are used for not too large memory blocks which * are believed not to stick around for too long. Using this API instead * of RTMemAlloc() not only gives the heap manager room for optimization * but makes the code easier to read. * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param cb Size in bytes of the memory block to allocated. */ RTDECL(void *) RTMemTmpAlloc(size_t cb) RT_NO_THROW { return RTMemAlloc(cb); } /** * Allocates zero'ed temporary memory. * * Same as RTMemTmpAlloc() but the memory will be zero'ed. * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param cb Size in bytes of the memory block to allocated. */ RTDECL(void *) RTMemTmpAllocZ(size_t cb) RT_NO_THROW { return RTMemAllocZ(cb); } /** * Free temporary memory. * * @param pv Pointer to memory block. */ RTDECL(void) RTMemTmpFree(void *pv) RT_NO_THROW { return RTMemFree(pv); } /** * Allocates memory. * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param cb Size in bytes of the memory block to allocated. */ RTDECL(void *) RTMemAlloc(size_t cb) RT_NO_THROW { PRTMEMHDR pHdr = rtMemAlloc(cb + RTR0MEM_FENCE_EXTRA, 0); if (pHdr) { #ifdef RTR0MEM_STRICT pHdr->cbReq = (uint32_t)cb; Assert(pHdr->cbReq == cb); memcpy((uint8_t *)(pHdr + 1) + cb, &g_abFence[0], RTR0MEM_FENCE_EXTRA); #endif return pHdr + 1; } return NULL; } /** * Allocates zero'ed memory. * * Instead of memset(pv, 0, sizeof()) use this when you want zero'ed * memory. This keeps the code smaller and the heap can skip the memset * in about 0.42% of calls :-). * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param cb Size in bytes of the memory block to allocated. */ RTDECL(void *) RTMemAllocZ(size_t cb) RT_NO_THROW { PRTMEMHDR pHdr = rtMemAlloc(cb + RTR0MEM_FENCE_EXTRA, RTMEMHDR_FLAG_ZEROED); if (pHdr) { #ifdef RTR0MEM_STRICT pHdr->cbReq = (uint32_t)cb; Assert(pHdr->cbReq == cb); memcpy((uint8_t *)(pHdr + 1) + cb, &g_abFence[0], RTR0MEM_FENCE_EXTRA); return memset(pHdr + 1, 0, cb); #else return memset(pHdr + 1, 0, pHdr->cb); #endif } return NULL; } /** * Reallocates memory. * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param pvOld The memory block to reallocate. * @param cbNew The new block size (in bytes). */ RTDECL(void *) RTMemRealloc(void *pvOld, size_t cbNew) RT_NO_THROW { if (!cbNew) RTMemFree(pvOld); else if (!pvOld) return RTMemAlloc(cbNew); else { PRTMEMHDR pHdrOld = (PRTMEMHDR)pvOld - 1; if (pHdrOld->u32Magic == RTMEMHDR_MAGIC) { PRTMEMHDR pHdrNew; if (pHdrOld->cb >= cbNew && pHdrOld->cb - cbNew <= 128) return pvOld; pHdrNew = rtMemAlloc(cbNew + RTR0MEM_FENCE_EXTRA, 0); if (pHdrNew) { size_t cbCopy = RT_MIN(pHdrOld->cb, pHdrNew->cb); memcpy(pHdrNew + 1, pvOld, cbCopy); #ifdef RTR0MEM_STRICT pHdrNew->cbReq = (uint32_t)cbNew; Assert(pHdrNew->cbReq == cbNew); memcpy((uint8_t *)(pHdrNew + 1) + cbNew, &g_abFence[0], RTR0MEM_FENCE_EXTRA); AssertReleaseMsg(!memcmp((uint8_t *)(pHdrOld + 1) + pHdrOld->cbReq, &g_abFence[0], RTR0MEM_FENCE_EXTRA), ("pHdr=%p pvOld=%p cb=%zu cbNew=%zu\n" "fence: %.*Rhxs\n" "expected: %.*Rhxs\n", pHdrOld, pvOld, pHdrOld->cb, cbNew, RTR0MEM_FENCE_EXTRA, (uint8_t *)(pHdrOld + 1) + pHdrOld->cb, RTR0MEM_FENCE_EXTRA, &g_abFence[0])); #endif rtMemFree(pHdrOld); return pHdrNew + 1; } } else AssertMsgFailed(("pHdrOld->u32Magic=%RX32 pvOld=%p cbNew=%#zx\n", pHdrOld->u32Magic, pvOld, cbNew)); } return NULL; } /** * Free memory related to an virtual machine * * @param pv Pointer to memory block. */ RTDECL(void) RTMemFree(void *pv) RT_NO_THROW { PRTMEMHDR pHdr; if (!pv) return; pHdr = (PRTMEMHDR)pv - 1; if (pHdr->u32Magic == RTMEMHDR_MAGIC) { Assert(!(pHdr->fFlags & RTMEMHDR_FLAG_EXEC)); #ifdef RTR0MEM_STRICT AssertReleaseMsg(!memcmp((uint8_t *)(pHdr + 1) + pHdr->cbReq, &g_abFence[0], RTR0MEM_FENCE_EXTRA), ("pHdr=%p pv=%p cb=%zu\n" "fence: %.*Rhxs\n" "expected: %.*Rhxs\n", pHdr, pv, pHdr->cb, RTR0MEM_FENCE_EXTRA, (uint8_t *)(pHdr + 1) + pHdr->cb, RTR0MEM_FENCE_EXTRA, &g_abFence[0])); #endif rtMemFree(pHdr); } else AssertMsgFailed(("pHdr->u32Magic=%RX32 pv=%p\n", pHdr->u32Magic, pv)); } /** * Allocates memory which may contain code. * * @returns Pointer to the allocated memory. * @returns NULL on failure. * @param cb Size in bytes of the memory block to allocate. */ RTDECL(void *) RTMemExecAlloc(size_t cb) RT_NO_THROW { PRTMEMHDR pHdr = rtMemAlloc(cb + RTR0MEM_FENCE_EXTRA, RTMEMHDR_FLAG_EXEC); if (pHdr) { #ifdef RTR0MEM_STRICT pHdr->cbReq = (uint32_t)cb; Assert(pHdr->cbReq == cb); memcpy((uint8_t *)(pHdr + 1) + cb, &g_abFence[0], RTR0MEM_FENCE_EXTRA); #endif return pHdr + 1; } return NULL; } /** * Free executable/read/write memory allocated by RTMemExecAlloc(). * * @param pv Pointer to memory block. */ RTDECL(void) RTMemExecFree(void *pv) RT_NO_THROW { PRTMEMHDR pHdr; if (!pv) return; pHdr = (PRTMEMHDR)pv - 1; if (pHdr->u32Magic == RTMEMHDR_MAGIC) { #ifdef RTR0MEM_STRICT AssertReleaseMsg(!memcmp((uint8_t *)(pHdr + 1) + pHdr->cbReq, &g_abFence[0], RTR0MEM_FENCE_EXTRA), ("pHdr=%p pv=%p cb=%zu\n" "fence: %.*Rhxs\n" "expected: %.*Rhxs\n", pHdr, pv, pHdr->cb, RTR0MEM_FENCE_EXTRA, (uint8_t *)(pHdr + 1) + pHdr->cb, RTR0MEM_FENCE_EXTRA, &g_abFence[0])); #endif rtMemFree(pHdr); } else AssertMsgFailed(("pHdr->u32Magic=%RX32 pv=%p\n", pHdr->u32Magic, pv)); }