/* $Id: alloc-win.cpp 11020 2008-07-30 22:48:35Z vboxsync $ */ /** @file * IPRT - Memory Allocation, Win32. */ /* * 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 * *******************************************************************************/ #define LOG_GROUP RTLOGGROUP_MEM #include #include #include #include #include #include #ifndef USE_VIRTUAL_ALLOC # include #endif /** * 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 { /* * Allocate first. */ AssertMsg(cb, ("Allocating ZERO bytes is really not a good idea! Good luck with the next assertion!\n")); cb = RT_ALIGN_Z(cb, 32); void *pv = malloc(cb); AssertMsg(pv, ("malloc(%d) failed!!!\n", cb)); if (pv) { /* * Add PROT_EXEC flag to the page. * * This is in violation of the SuS where I think it saith that mprotect() shall * only be used with mmap()'ed memory. Works on linux and OS/2 LIBC v0.6. */ memset(pv, 0xcc, cb); void *pvProt = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK); size_t cbProt = ((uintptr_t)pv & PAGE_OFFSET_MASK) + cb; cbProt = RT_ALIGN_Z(cbProt, PAGE_SIZE); DWORD fFlags = 0; if (!VirtualProtect(pvProt, cbProt, PAGE_EXECUTE_READWRITE, &fFlags)) { AssertMsgFailed(("VirtualProtect(%p, %#x,,) -> lasterr=%d\n", pvProt, cbProt, GetLastError())); free(pv); pv = NULL; } } return pv; } /** * Free executable/read/write memory allocated by RTMemExecAlloc(). * * @param pv Pointer to memory block. */ RTDECL(void) RTMemExecFree(void *pv) RT_NO_THROW { if (pv) free(pv); } /** * Allocate page aligned memory. * * @returns Pointer to the allocated memory. * @returns NULL if we're out of memory. * @param cb Size of the memory block. Will be rounded up to page size. */ RTDECL(void *) RTMemPageAlloc(size_t cb) RT_NO_THROW { #ifdef USE_VIRTUAL_ALLOC void *pv = VirtualAlloc(NULL, RT_ALIGN_Z(cb, PAGE_SIZE), MEM_COMMIT, PAGE_READWRITE); #else void *pv = _aligned_malloc(cb, PAGE_SIZE); #endif AssertMsg(pv, ("cb=%d lasterr=%d\n", cb, GetLastError())); return pv; } /** * Allocate zero'ed page aligned memory. * * @returns Pointer to the allocated memory. * @returns NULL if we're out of memory. * @param cb Size of the memory block. Will be rounded up to page size. */ RTDECL(void *) RTMemPageAllocZ(size_t cb) RT_NO_THROW { #ifdef USE_VIRTUAL_ALLOC void *pv = VirtualAlloc(NULL, RT_ALIGN_Z(cb, PAGE_SIZE), MEM_COMMIT, PAGE_READWRITE); #else void *pv = _aligned_malloc(cb, PAGE_SIZE); #endif if (pv) { memset(pv, 0, RT_ALIGN_Z(cb, PAGE_SIZE)); return pv; } AssertMsgFailed(("cb=%d lasterr=%d\n", cb, GetLastError())); return NULL; } /** * Free a memory block allocated with RTMemPageAlloc() or RTMemPageAllocZ(). * * @param pv Pointer to the block as it was returned by the allocation function. * NULL will be ignored. */ RTDECL(void) RTMemPageFree(void *pv) RT_NO_THROW { if (pv) { #ifdef USE_VIRTUAL_ALLOC if (!VirtualFree(pv, 0, MEM_RELEASE)) AssertMsgFailed(("pv=%p lasterr=%d\n", pv, GetLastError())); #else _aligned_free(pv); #endif } } /** * Change the page level protection of a memory region. * * @returns iprt status code. * @param pv Start of the region. Will be rounded down to nearest page boundary. * @param cb Size of the region. Will be rounded up to the nearest page boundary. * @param fProtect The new protection, a combination of the RTMEM_PROT_* defines. */ RTDECL(int) RTMemProtect(void *pv, size_t cb, unsigned fProtect) RT_NO_THROW { /* * Validate input. */ if (cb == 0) { AssertMsgFailed(("!cb\n")); return VERR_INVALID_PARAMETER; } if (fProtect & ~(RTMEM_PROT_NONE | RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC)) { AssertMsgFailed(("fProtect=%#x\n", fProtect)); return VERR_INVALID_PARAMETER; } /* * Convert the flags. */ int fProt; Assert(!RTMEM_PROT_NONE); switch (fProtect & (RTMEM_PROT_NONE | RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC)) { case RTMEM_PROT_NONE: fProt = PAGE_NOACCESS; break; case RTMEM_PROT_READ: fProt = PAGE_READONLY; break; case RTMEM_PROT_READ | RTMEM_PROT_WRITE: fProt = PAGE_READWRITE; break; case RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC: fProt = PAGE_EXECUTE_READWRITE; break; case RTMEM_PROT_READ | RTMEM_PROT_EXEC: fProt = PAGE_EXECUTE_READWRITE; break; case RTMEM_PROT_WRITE: fProt = PAGE_READWRITE; break; case RTMEM_PROT_WRITE | RTMEM_PROT_EXEC: fProt = PAGE_EXECUTE_READWRITE; break; case RTMEM_PROT_EXEC: fProt = PAGE_EXECUTE_READWRITE; break; /* If the compiler had any brains it would warn about this case. */ default: AssertMsgFailed(("fProtect=%#x\n", fProtect)); return VERR_INTERNAL_ERROR; } /* * Align the request. */ cb += (uintptr_t)pv & PAGE_OFFSET_MASK; pv = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK); /* * Change the page attributes. */ DWORD fFlags = 0; if (VirtualProtect(pv, cb, fProt, &fFlags)) return VINF_SUCCESS; return RTErrConvertFromWin32(GetLastError()); }