VirtualBox

source: vbox/trunk/src/VBox/Runtime/r3/posix/alloc-posix.cpp@ 31158

Last change on this file since 31158 was 31158, checked in by vboxsync, 14 years ago

iprt,++: Tag allocation in all builds with a string, defaulting to FILE.

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1/* $Id: alloc-posix.cpp 31158 2010-07-28 03:24:30Z vboxsync $ */
2/** @file
3 * IPRT - Memory Allocation, POSIX.
4 */
5
6/*
7 * Copyright (C) 2006-2010 Oracle Corporation
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 *
17 * The contents of this file may alternatively be used under the terms
18 * of the Common Development and Distribution License Version 1.0
19 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20 * VirtualBox OSE distribution, in which case the provisions of the
21 * CDDL are applicable instead of those of the GPL.
22 *
23 * You may elect to license modified versions of this file under the
24 * terms and conditions of either the GPL or the CDDL or both.
25 */
26
27
28/*******************************************************************************
29* Header Files *
30*******************************************************************************/
31#include <iprt/alloc.h>
32#include <iprt/assert.h>
33#include <iprt/param.h>
34#include <iprt/err.h>
35#include <iprt/string.h>
36
37#include <stdlib.h>
38#ifndef RT_OS_FREEBSD /* Deprecated on FreeBSD */
39# include <malloc.h>
40#endif
41#include <errno.h>
42#include <sys/mman.h>
43
44
45/*******************************************************************************
46* Defined Constants And Macros *
47*******************************************************************************/
48#if !defined(RT_USE_MMAP_EXEC) && (defined(RT_OS_LINUX))
49# define RT_USE_MMAP_EXEC
50#endif
51
52#if !defined(RT_USE_MMAP_PAGE) && 0 /** @todo mmap is too slow for full scale EF setup. */
53# define RT_USE_MMAP_PAGE
54#endif
55
56
57/*******************************************************************************
58* Structures and Typedefs *
59*******************************************************************************/
60#ifdef RT_USE_MMAP_EXEC
61/**
62 * RTMemExecAlloc() header used when using mmap for allocating the memory.
63 */
64typedef struct RTMEMEXECHDR
65{
66 /** Magic number (RTMEMEXECHDR_MAGIC). */
67 size_t uMagic;
68 /** The size we requested from mmap. */
69 size_t cb;
70# if ARCH_BITS == 32
71 uint32_t Alignment[2];
72# endif
73} RTMEMEXECHDR, *PRTMEMEXECHDR;
74
75/** Magic for RTMEMEXECHDR. */
76# define RTMEMEXECHDR_MAGIC (~(size_t)0xfeedbabe)
77
78#endif /* RT_USE_MMAP_EXEC */
79
80
81
82RTDECL(void *) RTMemExecAllocTag(size_t cb, const char *pszTag) RT_NO_THROW
83{
84 AssertMsg(cb, ("Allocating ZERO bytes is really not a good idea! Good luck with the next assertion!\n"));
85
86#ifdef RT_USE_MMAP_EXEC
87 /*
88 * Use mmap to get low memory.
89 */
90 size_t cbAlloc = RT_ALIGN_Z(cb + sizeof(RTMEMEXECHDR), PAGE_SIZE);
91 void *pv = mmap(NULL, cbAlloc, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS
92# if defined(RT_ARCH_AMD64) && defined(MAP_32BIT)
93 | MAP_32BIT
94# endif
95 , -1, 0);
96 AssertMsgReturn(pv != MAP_FAILED, ("errno=%d cb=%#zx\n", errno, cb), NULL);
97 PRTMEMEXECHDR pHdr = (PRTMEMEXECHDR)pv;
98 pHdr->uMagic = RTMEMEXECHDR_MAGIC;
99 pHdr->cb = cbAlloc;
100 pv = pHdr + 1;
101
102#else
103 /*
104 * Allocate first.
105 */
106 cb = RT_ALIGN_Z(cb, 32);
107 void *pv = NULL;
108 int rc = posix_memalign(&pv, 32, cb);
109 AssertMsg(!rc && pv, ("posix_memalign(%zd) failed!!! rc=%d\n", cb, rc));
110 if (pv && !rc)
111 {
112 /*
113 * Add PROT_EXEC flag to the page.
114 *
115 * This is in violation of the SuS where I think it saith that mprotect() shall
116 * only be used with mmap()'ed memory. Works on linux and OS/2 LIBC v0.6.
117 */
118 memset(pv, 0xcc, cb);
119 void *pvProt = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK);
120 size_t cbProt = ((uintptr_t)pv & PAGE_OFFSET_MASK) + cb;
121 cbProt = RT_ALIGN_Z(cbProt, PAGE_SIZE);
122 rc = mprotect(pvProt, cbProt, PROT_READ | PROT_WRITE | PROT_EXEC);
123 if (rc)
124 {
125 AssertMsgFailed(("mprotect(%p, %#zx,,) -> rc=%d, errno=%d\n", pvProt, cbProt, rc, errno));
126 free(pv);
127 pv = NULL;
128 }
129 }
130#endif
131 return pv;
132}
133
134
135RTDECL(void) RTMemExecFree(void *pv) RT_NO_THROW
136{
137 if (pv)
138 {
139#ifdef RT_USE_MMAP_EXEC
140 PRTMEMEXECHDR pHdr = (PRTMEMEXECHDR)pv - 1;
141 AssertMsgReturnVoid(RT_ALIGN_P(pHdr, PAGE_SIZE) == pHdr, ("pHdr=%p pv=%p\n", pHdr, pv));
142 AssertMsgReturnVoid(pHdr->uMagic == RTMEMEXECHDR_MAGIC, ("pHdr=%p(uMagic=%#zx) pv=%p\n", pHdr, pHdr->uMagic, pv));
143 int rc = munmap(pHdr, pHdr->cb);
144 AssertMsg(!rc, ("munmap -> %d errno=%d\n", rc, errno)); NOREF(rc);
145#else
146 free(pv);
147#endif
148 }
149}
150
151
152RTDECL(void *) RTMemPageAllocTag(size_t cb, const char *pszTag) RT_NO_THROW
153{
154#ifdef RT_USE_MMAP_PAGE
155 size_t cbAligned = RT_ALIGN_Z(cb, PAGE_SIZE);
156 void *pv = mmap(NULL, cbAligned, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
157 AssertMsgReturn(pv != MAP_FAILED, ("errno=%d cb=%#zx\n", errno, cb), NULL);
158 return pv;
159
160#else
161# if defined(RT_OS_FREEBSD) /** @todo huh? we're using posix_memalign in the next function... */
162 void *pv;
163 int rc = posix_memalign(&pv, PAGE_SIZE, RT_ALIGN_Z(cb, PAGE_SIZE));
164 if (!rc)
165 return pv;
166 return NULL;
167# else /* !RT_OS_FREEBSD */
168 return memalign(PAGE_SIZE, cb);
169# endif
170#endif
171}
172
173
174RTDECL(void *) RTMemPageAllocZTag(size_t cb, const char *pszTag) RT_NO_THROW
175{
176#ifdef RT_USE_MMAP_PAGE
177 size_t cbAligned = RT_ALIGN_Z(cb, PAGE_SIZE);
178 void *pv = mmap(NULL, cbAligned, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
179 AssertMsgReturn(pv != MAP_FAILED, ("errno=%d cb=%#zx\n", errno, cb), NULL);
180 return pv;
181
182#else
183 void *pv;
184 int rc = posix_memalign(&pv, PAGE_SIZE, RT_ALIGN_Z(cb, PAGE_SIZE));
185 if (!rc)
186 {
187 RT_BZERO(pv, RT_ALIGN_Z(cb, PAGE_SIZE));
188 return pv;
189 }
190 return NULL;
191#endif
192}
193
194
195RTDECL(void) RTMemPageFree(void *pv, size_t cb) RT_NO_THROW
196{
197 if (pv)
198 {
199 Assert(!((uintptr_t)pv & PAGE_OFFSET_MASK));
200
201#ifdef RT_USE_MMAP_PAGE
202 size_t cbAligned = RT_ALIGN_Z(cb, PAGE_SIZE);
203 int rc = munmap(pv, cbAligned);
204 AssertMsg(!rc, ("munmap(%p, %#zx) -> %d errno=%d\n", pv, cbAligned, rc, errno)); NOREF(rc);
205#else
206 free(pv);
207#endif
208 }
209}
210
211
212RTDECL(int) RTMemProtect(void *pv, size_t cb, unsigned fProtect) RT_NO_THROW
213{
214 /*
215 * Validate input.
216 */
217 if (cb == 0)
218 {
219 AssertMsgFailed(("!cb\n"));
220 return VERR_INVALID_PARAMETER;
221 }
222 if (fProtect & ~(RTMEM_PROT_NONE | RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC))
223 {
224 AssertMsgFailed(("fProtect=%#x\n", fProtect));
225 return VERR_INVALID_PARAMETER;
226 }
227
228 /*
229 * Convert the flags.
230 */
231 int fProt;
232#if RTMEM_PROT_NONE == PROT_NONE \
233 && RTMEM_PROT_READ == PROT_READ \
234 && RTMEM_PROT_WRITE == PROT_WRITE \
235 && RTMEM_PROT_EXEC == PROT_EXEC
236 fProt = fProtect;
237#else
238 Assert(!RTMEM_PROT_NONE);
239 if (!fProtect)
240 fProt = PROT_NONE;
241 else
242 {
243 fProt = 0;
244 if (fProtect & RTMEM_PROT_READ)
245 fProt |= PROT_READ;
246 if (fProtect & RTMEM_PROT_WRITE)
247 fProt |= PROT_WRITE;
248 if (fProtect & RTMEM_PROT_EXEC)
249 fProt |= PROT_EXEC;
250 }
251#endif
252
253 /*
254 * Align the request.
255 */
256 cb += (uintptr_t)pv & PAGE_OFFSET_MASK;
257 pv = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK);
258
259 /*
260 * Change the page attributes.
261 */
262 int rc = mprotect(pv, cb, fProt);
263 if (!rc)
264 return rc;
265 return RTErrConvertFromErrno(errno);
266}
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