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1 | 54936004 | bellard | /*
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2 | 54936004 | bellard | * mmap support for qemu
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3 | 5fafdf24 | ths | *
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4 | 54936004 | bellard | * Copyright (c) 2003 Fabrice Bellard
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5 | 54936004 | bellard | *
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6 | 54936004 | bellard | * This program is free software; you can redistribute it and/or modify
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7 | 54936004 | bellard | * it under the terms of the GNU General Public License as published by
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8 | 54936004 | bellard | * the Free Software Foundation; either version 2 of the License, or
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9 | 54936004 | bellard | * (at your option) any later version.
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10 | 54936004 | bellard | *
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11 | 54936004 | bellard | * This program is distributed in the hope that it will be useful,
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12 | 54936004 | bellard | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | 54936004 | bellard | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 | 54936004 | bellard | * GNU General Public License for more details.
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15 | 54936004 | bellard | *
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16 | 54936004 | bellard | * You should have received a copy of the GNU General Public License
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17 | 54936004 | bellard | * along with this program; if not, write to the Free Software
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18 | 530e7615 | blueswir1 | * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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19 | 530e7615 | blueswir1 | * MA 02110-1301, USA.
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20 | 54936004 | bellard | */
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21 | 54936004 | bellard | #include <stdlib.h> |
22 | 54936004 | bellard | #include <stdio.h> |
23 | 54936004 | bellard | #include <stdarg.h> |
24 | 54936004 | bellard | #include <string.h> |
25 | 54936004 | bellard | #include <unistd.h> |
26 | 54936004 | bellard | #include <errno.h> |
27 | 54c5a2ae | edgar_igl | #include <sys/types.h> |
28 | 54c5a2ae | edgar_igl | #include <sys/stat.h> |
29 | 54936004 | bellard | #include <sys/mman.h> |
30 | 3af72a4d | blueswir1 | #include <linux/mman.h> |
31 | 3af72a4d | blueswir1 | #include <linux/unistd.h> |
32 | 54936004 | bellard | |
33 | 54936004 | bellard | #include "qemu.h" |
34 | 78f5bf1e | blueswir1 | #include "qemu-common.h" |
35 | 54936004 | bellard | |
36 | 54936004 | bellard | //#define DEBUG_MMAP
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37 | 54936004 | bellard | |
38 | c8a706fe | pbrook | #if defined(USE_NPTL)
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39 | c8a706fe | pbrook | pthread_mutex_t mmap_mutex; |
40 | c8a706fe | pbrook | static int __thread mmap_lock_count; |
41 | c8a706fe | pbrook | |
42 | c8a706fe | pbrook | void mmap_lock(void) |
43 | c8a706fe | pbrook | { |
44 | c8a706fe | pbrook | if (mmap_lock_count++ == 0) { |
45 | c8a706fe | pbrook | pthread_mutex_lock(&mmap_mutex); |
46 | c8a706fe | pbrook | } |
47 | c8a706fe | pbrook | } |
48 | c8a706fe | pbrook | |
49 | c8a706fe | pbrook | void mmap_unlock(void) |
50 | c8a706fe | pbrook | { |
51 | c8a706fe | pbrook | if (--mmap_lock_count == 0) { |
52 | c8a706fe | pbrook | pthread_mutex_unlock(&mmap_mutex); |
53 | c8a706fe | pbrook | } |
54 | c8a706fe | pbrook | } |
55 | d5975363 | pbrook | |
56 | d5975363 | pbrook | /* Grab lock to make sure things are in a consistent state after fork(). */
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57 | d5975363 | pbrook | void mmap_fork_start(void) |
58 | d5975363 | pbrook | { |
59 | d5975363 | pbrook | if (mmap_lock_count)
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60 | d5975363 | pbrook | abort(); |
61 | d5975363 | pbrook | pthread_mutex_lock(&mmap_mutex); |
62 | d5975363 | pbrook | } |
63 | d5975363 | pbrook | |
64 | d5975363 | pbrook | void mmap_fork_end(int child) |
65 | d5975363 | pbrook | { |
66 | d5975363 | pbrook | if (child)
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67 | d5975363 | pbrook | pthread_mutex_init(&mmap_mutex, NULL);
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68 | d5975363 | pbrook | else
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69 | d5975363 | pbrook | pthread_mutex_unlock(&mmap_mutex); |
70 | d5975363 | pbrook | } |
71 | c8a706fe | pbrook | #else
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72 | c8a706fe | pbrook | /* We aren't threadsafe to start with, so no need to worry about locking. */
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73 | c8a706fe | pbrook | void mmap_lock(void) |
74 | c8a706fe | pbrook | { |
75 | c8a706fe | pbrook | } |
76 | c8a706fe | pbrook | |
77 | c8a706fe | pbrook | void mmap_unlock(void) |
78 | c8a706fe | pbrook | { |
79 | c8a706fe | pbrook | } |
80 | c8a706fe | pbrook | #endif
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81 | c8a706fe | pbrook | |
82 | 17e2377a | pbrook | void *qemu_vmalloc(size_t size)
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83 | 17e2377a | pbrook | { |
84 | 17e2377a | pbrook | void *p;
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85 | 17e2377a | pbrook | unsigned long addr; |
86 | 17e2377a | pbrook | mmap_lock(); |
87 | 17e2377a | pbrook | /* Use map and mark the pages as used. */
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88 | 17e2377a | pbrook | p = mmap(NULL, size, PROT_READ | PROT_WRITE,
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89 | 17e2377a | pbrook | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
90 | 17e2377a | pbrook | |
91 | 17e2377a | pbrook | addr = (unsigned long)p; |
92 | 17e2377a | pbrook | if (addr == (target_ulong) addr) {
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93 | 17e2377a | pbrook | /* Allocated region overlaps guest address space.
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94 | 17e2377a | pbrook | This may recurse. */
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95 | 17e2377a | pbrook | page_set_flags(addr & TARGET_PAGE_MASK, TARGET_PAGE_ALIGN(addr + size), |
96 | 17e2377a | pbrook | PAGE_RESERVED); |
97 | 17e2377a | pbrook | } |
98 | 17e2377a | pbrook | |
99 | 17e2377a | pbrook | mmap_unlock(); |
100 | 17e2377a | pbrook | return p;
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101 | 17e2377a | pbrook | } |
102 | 17e2377a | pbrook | |
103 | 17e2377a | pbrook | void *qemu_malloc(size_t size)
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104 | 17e2377a | pbrook | { |
105 | 17e2377a | pbrook | char * p;
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106 | 17e2377a | pbrook | size += 16;
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107 | 17e2377a | pbrook | p = qemu_vmalloc(size); |
108 | 17e2377a | pbrook | *(size_t *)p = size; |
109 | 17e2377a | pbrook | return p + 16; |
110 | 17e2377a | pbrook | } |
111 | 17e2377a | pbrook | |
112 | 17e2377a | pbrook | /* We use map, which is always zero initialized. */
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113 | 17e2377a | pbrook | void * qemu_mallocz(size_t size)
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114 | 17e2377a | pbrook | { |
115 | 17e2377a | pbrook | return qemu_malloc(size);
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116 | 17e2377a | pbrook | } |
117 | 17e2377a | pbrook | |
118 | 17e2377a | pbrook | void qemu_free(void *ptr) |
119 | 17e2377a | pbrook | { |
120 | 17e2377a | pbrook | /* FIXME: We should unmark the reserved pages here. However this gets
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121 | 17e2377a | pbrook | complicated when one target page spans multiple host pages, so we
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122 | 17e2377a | pbrook | don't bother. */
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123 | 17e2377a | pbrook | size_t *p; |
124 | 17e2377a | pbrook | p = (size_t *)((char *)ptr - 16); |
125 | 17e2377a | pbrook | munmap(p, *p); |
126 | 17e2377a | pbrook | } |
127 | 17e2377a | pbrook | |
128 | 1a6f0dbc | aliguori | void *qemu_realloc(void *ptr, size_t size) |
129 | 1a6f0dbc | aliguori | { |
130 | 1a6f0dbc | aliguori | size_t old_size, copy; |
131 | 1a6f0dbc | aliguori | void *new_ptr;
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132 | 1a6f0dbc | aliguori | |
133 | baa8c602 | malc | if (!ptr)
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134 | baa8c602 | malc | return qemu_malloc(size);
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135 | 1a6f0dbc | aliguori | old_size = *(size_t *)((char *)ptr - 16); |
136 | 1a6f0dbc | aliguori | copy = old_size < size ? old_size : size; |
137 | 1a6f0dbc | aliguori | new_ptr = qemu_malloc(size); |
138 | 1a6f0dbc | aliguori | memcpy(new_ptr, ptr, copy); |
139 | 1a6f0dbc | aliguori | qemu_free(ptr); |
140 | 1a6f0dbc | aliguori | return new_ptr;
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141 | 1a6f0dbc | aliguori | } |
142 | 1a6f0dbc | aliguori | |
143 | 53a5960a | pbrook | /* NOTE: all the constants are the HOST ones, but addresses are target. */
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144 | 992f48a0 | blueswir1 | int target_mprotect(abi_ulong start, abi_ulong len, int prot) |
145 | 54936004 | bellard | { |
146 | 992f48a0 | blueswir1 | abi_ulong end, host_start, host_end, addr; |
147 | 54936004 | bellard | int prot1, ret;
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148 | 54936004 | bellard | |
149 | 54936004 | bellard | #ifdef DEBUG_MMAP
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150 | a5b85f79 | ths | printf("mprotect: start=0x" TARGET_FMT_lx
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151 | 80210bcd | ths | "len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len, |
152 | 54936004 | bellard | prot & PROT_READ ? 'r' : '-', |
153 | 54936004 | bellard | prot & PROT_WRITE ? 'w' : '-', |
154 | 54936004 | bellard | prot & PROT_EXEC ? 'x' : '-'); |
155 | 54936004 | bellard | #endif
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156 | 54936004 | bellard | |
157 | 54936004 | bellard | if ((start & ~TARGET_PAGE_MASK) != 0) |
158 | 54936004 | bellard | return -EINVAL;
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159 | 54936004 | bellard | len = TARGET_PAGE_ALIGN(len); |
160 | 54936004 | bellard | end = start + len; |
161 | 54936004 | bellard | if (end < start)
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162 | 54936004 | bellard | return -EINVAL;
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163 | 171cd1cd | balrog | prot &= PROT_READ | PROT_WRITE | PROT_EXEC; |
164 | 54936004 | bellard | if (len == 0) |
165 | 54936004 | bellard | return 0; |
166 | 3b46e624 | ths | |
167 | c8a706fe | pbrook | mmap_lock(); |
168 | 83fb7adf | bellard | host_start = start & qemu_host_page_mask; |
169 | 54936004 | bellard | host_end = HOST_PAGE_ALIGN(end); |
170 | 54936004 | bellard | if (start > host_start) {
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171 | 54936004 | bellard | /* handle host page containing start */
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172 | 54936004 | bellard | prot1 = prot; |
173 | 54936004 | bellard | for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
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174 | 54936004 | bellard | prot1 |= page_get_flags(addr); |
175 | 54936004 | bellard | } |
176 | 83fb7adf | bellard | if (host_end == host_start + qemu_host_page_size) {
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177 | d418c81e | bellard | for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
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178 | d418c81e | bellard | prot1 |= page_get_flags(addr); |
179 | d418c81e | bellard | } |
180 | d418c81e | bellard | end = host_end; |
181 | d418c81e | bellard | } |
182 | 53a5960a | pbrook | ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS); |
183 | 54936004 | bellard | if (ret != 0) |
184 | c8a706fe | pbrook | goto error;
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185 | 83fb7adf | bellard | host_start += qemu_host_page_size; |
186 | 54936004 | bellard | } |
187 | 54936004 | bellard | if (end < host_end) {
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188 | 54936004 | bellard | prot1 = prot; |
189 | 54936004 | bellard | for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
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190 | 54936004 | bellard | prot1 |= page_get_flags(addr); |
191 | 54936004 | bellard | } |
192 | 5fafdf24 | ths | ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size, |
193 | 54936004 | bellard | prot1 & PAGE_BITS); |
194 | 54936004 | bellard | if (ret != 0) |
195 | c8a706fe | pbrook | goto error;
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196 | 83fb7adf | bellard | host_end -= qemu_host_page_size; |
197 | 54936004 | bellard | } |
198 | 3b46e624 | ths | |
199 | 54936004 | bellard | /* handle the pages in the middle */
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200 | 54936004 | bellard | if (host_start < host_end) {
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201 | 53a5960a | pbrook | ret = mprotect(g2h(host_start), host_end - host_start, prot); |
202 | 54936004 | bellard | if (ret != 0) |
203 | c8a706fe | pbrook | goto error;
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204 | 54936004 | bellard | } |
205 | 54936004 | bellard | page_set_flags(start, start + len, prot | PAGE_VALID); |
206 | c8a706fe | pbrook | mmap_unlock(); |
207 | 54936004 | bellard | return 0; |
208 | c8a706fe | pbrook | error:
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209 | c8a706fe | pbrook | mmap_unlock(); |
210 | c8a706fe | pbrook | return ret;
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211 | 54936004 | bellard | } |
212 | 54936004 | bellard | |
213 | 54936004 | bellard | /* map an incomplete host page */
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214 | 992f48a0 | blueswir1 | static int mmap_frag(abi_ulong real_start, |
215 | 992f48a0 | blueswir1 | abi_ulong start, abi_ulong end, |
216 | 992f48a0 | blueswir1 | int prot, int flags, int fd, abi_ulong offset) |
217 | 54936004 | bellard | { |
218 | 80210bcd | ths | abi_ulong real_end, addr; |
219 | 53a5960a | pbrook | void *host_start;
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220 | 54936004 | bellard | int prot1, prot_new;
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221 | 54936004 | bellard | |
222 | 53a5960a | pbrook | real_end = real_start + qemu_host_page_size; |
223 | 53a5960a | pbrook | host_start = g2h(real_start); |
224 | 54936004 | bellard | |
225 | 54936004 | bellard | /* get the protection of the target pages outside the mapping */
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226 | 54936004 | bellard | prot1 = 0;
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227 | 53a5960a | pbrook | for(addr = real_start; addr < real_end; addr++) {
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228 | 54936004 | bellard | if (addr < start || addr >= end)
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229 | 54936004 | bellard | prot1 |= page_get_flags(addr); |
230 | 54936004 | bellard | } |
231 | 3b46e624 | ths | |
232 | 54936004 | bellard | if (prot1 == 0) { |
233 | 54936004 | bellard | /* no page was there, so we allocate one */
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234 | 80210bcd | ths | void *p = mmap(host_start, qemu_host_page_size, prot,
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235 | 80210bcd | ths | flags | MAP_ANONYMOUS, -1, 0); |
236 | 80210bcd | ths | if (p == MAP_FAILED)
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237 | 80210bcd | ths | return -1; |
238 | 53a5960a | pbrook | prot1 = prot; |
239 | 54936004 | bellard | } |
240 | 54936004 | bellard | prot1 &= PAGE_BITS; |
241 | 54936004 | bellard | |
242 | 54936004 | bellard | prot_new = prot | prot1; |
243 | 54936004 | bellard | if (!(flags & MAP_ANONYMOUS)) {
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244 | 54936004 | bellard | /* msync() won't work here, so we return an error if write is
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245 | 54936004 | bellard | possible while it is a shared mapping */
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246 | 54936004 | bellard | if ((flags & MAP_TYPE) == MAP_SHARED &&
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247 | 54936004 | bellard | (prot & PROT_WRITE)) |
248 | 54936004 | bellard | return -EINVAL;
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249 | 54936004 | bellard | |
250 | 54936004 | bellard | /* adjust protection to be able to read */
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251 | 54936004 | bellard | if (!(prot1 & PROT_WRITE))
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252 | 53a5960a | pbrook | mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE); |
253 | 3b46e624 | ths | |
254 | 54936004 | bellard | /* read the corresponding file data */
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255 | 53a5960a | pbrook | pread(fd, g2h(start), end - start, offset); |
256 | 3b46e624 | ths | |
257 | 54936004 | bellard | /* put final protection */
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258 | 54936004 | bellard | if (prot_new != (prot1 | PROT_WRITE))
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259 | 53a5960a | pbrook | mprotect(host_start, qemu_host_page_size, prot_new); |
260 | 54936004 | bellard | } else {
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261 | 54936004 | bellard | /* just update the protection */
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262 | 54936004 | bellard | if (prot_new != prot1) {
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263 | 53a5960a | pbrook | mprotect(host_start, qemu_host_page_size, prot_new); |
264 | 54936004 | bellard | } |
265 | 54936004 | bellard | } |
266 | 54936004 | bellard | return 0; |
267 | 54936004 | bellard | } |
268 | 54936004 | bellard | |
269 | a03e2d42 | bellard | #if defined(__CYGWIN__)
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270 | a03e2d42 | bellard | /* Cygwin doesn't have a whole lot of address space. */
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271 | a03e2d42 | bellard | static abi_ulong mmap_next_start = 0x18000000; |
272 | a03e2d42 | bellard | #else
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273 | a03e2d42 | bellard | static abi_ulong mmap_next_start = 0x40000000; |
274 | a03e2d42 | bellard | #endif
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275 | a03e2d42 | bellard | |
276 | 0776590d | pbrook | unsigned long last_brk; |
277 | 0776590d | pbrook | |
278 | a03e2d42 | bellard | /* find a free memory area of size 'size'. The search starts at
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279 | a03e2d42 | bellard | 'start'. If 'start' == 0, then a default start address is used.
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280 | a03e2d42 | bellard | Return -1 if error.
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281 | a03e2d42 | bellard | */
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282 | 50a9569b | balrog | /* page_init() marks pages used by the host as reserved to be sure not
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283 | a03e2d42 | bellard | to use them. */
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284 | a03e2d42 | bellard | static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
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285 | a03e2d42 | bellard | { |
286 | a03e2d42 | bellard | abi_ulong addr, addr1, addr_start; |
287 | a03e2d42 | bellard | int prot;
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288 | 0776590d | pbrook | unsigned long new_brk; |
289 | 0776590d | pbrook | |
290 | 0776590d | pbrook | new_brk = (unsigned long)sbrk(0); |
291 | 0776590d | pbrook | if (last_brk && last_brk < new_brk && last_brk == (target_ulong)last_brk) {
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292 | 0776590d | pbrook | /* This is a hack to catch the host allocating memory with brk().
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293 | 0776590d | pbrook | If it uses mmap then we loose.
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294 | 0776590d | pbrook | FIXME: We really want to avoid the host allocating memory in
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295 | 0776590d | pbrook | the first place, and maybe leave some slack to avoid switching
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296 | 0776590d | pbrook | to mmap. */
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297 | 0776590d | pbrook | page_set_flags(last_brk & TARGET_PAGE_MASK, |
298 | 0776590d | pbrook | TARGET_PAGE_ALIGN(new_brk), |
299 | 0776590d | pbrook | PAGE_RESERVED); |
300 | 0776590d | pbrook | } |
301 | 0776590d | pbrook | last_brk = new_brk; |
302 | a03e2d42 | bellard | |
303 | a03e2d42 | bellard | size = HOST_PAGE_ALIGN(size); |
304 | a03e2d42 | bellard | start = start & qemu_host_page_mask; |
305 | a03e2d42 | bellard | addr = start; |
306 | a03e2d42 | bellard | if (addr == 0) |
307 | a03e2d42 | bellard | addr = mmap_next_start; |
308 | a03e2d42 | bellard | addr_start = addr; |
309 | a03e2d42 | bellard | for(;;) {
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310 | a03e2d42 | bellard | prot = 0;
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311 | a03e2d42 | bellard | for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
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312 | a03e2d42 | bellard | prot |= page_get_flags(addr1); |
313 | a03e2d42 | bellard | } |
314 | a03e2d42 | bellard | if (prot == 0) |
315 | a03e2d42 | bellard | break;
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316 | a03e2d42 | bellard | addr += qemu_host_page_size; |
317 | a03e2d42 | bellard | /* we found nothing */
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318 | a03e2d42 | bellard | if (addr == addr_start)
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319 | a03e2d42 | bellard | return (abi_ulong)-1; |
320 | a03e2d42 | bellard | } |
321 | a03e2d42 | bellard | if (start == 0) |
322 | a03e2d42 | bellard | mmap_next_start = addr + size; |
323 | a03e2d42 | bellard | return addr;
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324 | a03e2d42 | bellard | } |
325 | a03e2d42 | bellard | |
326 | 54936004 | bellard | /* NOTE: all the constants are the HOST ones */
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327 | 992f48a0 | blueswir1 | abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
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328 | 992f48a0 | blueswir1 | int flags, int fd, abi_ulong offset) |
329 | 54936004 | bellard | { |
330 | 992f48a0 | blueswir1 | abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len; |
331 | a5b85f79 | ths | unsigned long host_start; |
332 | 54936004 | bellard | |
333 | c8a706fe | pbrook | mmap_lock(); |
334 | 54936004 | bellard | #ifdef DEBUG_MMAP
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335 | 54936004 | bellard | { |
336 | a5b85f79 | ths | printf("mmap: start=0x" TARGET_FMT_lx
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337 | 80210bcd | ths | " len=0x" TARGET_FMT_lx " prot=%c%c%c flags=", |
338 | 5fafdf24 | ths | start, len, |
339 | 54936004 | bellard | prot & PROT_READ ? 'r' : '-', |
340 | 54936004 | bellard | prot & PROT_WRITE ? 'w' : '-', |
341 | 54936004 | bellard | prot & PROT_EXEC ? 'x' : '-'); |
342 | 54936004 | bellard | if (flags & MAP_FIXED)
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343 | 54936004 | bellard | printf("MAP_FIXED ");
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344 | 54936004 | bellard | if (flags & MAP_ANONYMOUS)
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345 | 54936004 | bellard | printf("MAP_ANON ");
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346 | 54936004 | bellard | switch(flags & MAP_TYPE) {
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347 | 54936004 | bellard | case MAP_PRIVATE:
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348 | 54936004 | bellard | printf("MAP_PRIVATE ");
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349 | 54936004 | bellard | break;
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350 | 54936004 | bellard | case MAP_SHARED:
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351 | 54936004 | bellard | printf("MAP_SHARED ");
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352 | 54936004 | bellard | break;
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353 | 54936004 | bellard | default:
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354 | 54936004 | bellard | printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
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355 | 54936004 | bellard | break;
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356 | 54936004 | bellard | } |
357 | a5b85f79 | ths | printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset); |
358 | 54936004 | bellard | } |
359 | 54936004 | bellard | #endif
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360 | 54936004 | bellard | |
361 | e89f07d3 | pbrook | if (offset & ~TARGET_PAGE_MASK) {
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362 | e89f07d3 | pbrook | errno = EINVAL; |
363 | c8a706fe | pbrook | goto fail;
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364 | e89f07d3 | pbrook | } |
365 | 54936004 | bellard | |
366 | 54936004 | bellard | len = TARGET_PAGE_ALIGN(len); |
367 | 54936004 | bellard | if (len == 0) |
368 | c8a706fe | pbrook | goto the_end;
|
369 | 53a5960a | pbrook | real_start = start & qemu_host_page_mask; |
370 | 54936004 | bellard | |
371 | 54c5a2ae | edgar_igl | /* When mapping files into a memory area larger than the file, accesses
|
372 | 54c5a2ae | edgar_igl | to pages beyond the file size will cause a SIGBUS.
|
373 | 54c5a2ae | edgar_igl | |
374 | 54c5a2ae | edgar_igl | For example, if mmaping a file of 100 bytes on a host with 4K pages
|
375 | 54c5a2ae | edgar_igl | emulating a target with 8K pages, the target expects to be able to
|
376 | 54c5a2ae | edgar_igl | access the first 8K. But the host will trap us on any access beyond
|
377 | 54c5a2ae | edgar_igl | 4K.
|
378 | 54c5a2ae | edgar_igl | |
379 | 54c5a2ae | edgar_igl | When emulating a target with a larger page-size than the hosts, we
|
380 | 54c5a2ae | edgar_igl | may need to truncate file maps at EOF and add extra anonymous pages
|
381 | 54c5a2ae | edgar_igl | up to the targets page boundary. */
|
382 | 54c5a2ae | edgar_igl | |
383 | 54c5a2ae | edgar_igl | if ((qemu_real_host_page_size < TARGET_PAGE_SIZE)
|
384 | 54c5a2ae | edgar_igl | && !(flags & MAP_ANONYMOUS)) { |
385 | 54c5a2ae | edgar_igl | struct stat sb;
|
386 | 54c5a2ae | edgar_igl | |
387 | 54c5a2ae | edgar_igl | if (fstat (fd, &sb) == -1) |
388 | 54c5a2ae | edgar_igl | goto fail;
|
389 | 54c5a2ae | edgar_igl | |
390 | 54c5a2ae | edgar_igl | /* Are we trying to create a map beyond EOF?. */
|
391 | 54c5a2ae | edgar_igl | if (offset + len > sb.st_size) {
|
392 | 54c5a2ae | edgar_igl | /* If so, truncate the file map at eof aligned with
|
393 | 54c5a2ae | edgar_igl | the hosts real pagesize. Additional anonymous maps
|
394 | 54c5a2ae | edgar_igl | will be created beyond EOF. */
|
395 | 54c5a2ae | edgar_igl | len = (sb.st_size - offset); |
396 | 54c5a2ae | edgar_igl | len += qemu_real_host_page_size - 1;
|
397 | 54c5a2ae | edgar_igl | len &= ~(qemu_real_host_page_size - 1);
|
398 | 54c5a2ae | edgar_igl | } |
399 | 54c5a2ae | edgar_igl | } |
400 | 54c5a2ae | edgar_igl | |
401 | 54936004 | bellard | if (!(flags & MAP_FIXED)) {
|
402 | a03e2d42 | bellard | abi_ulong mmap_start; |
403 | a03e2d42 | bellard | void *p;
|
404 | a03e2d42 | bellard | host_offset = offset & qemu_host_page_mask; |
405 | a03e2d42 | bellard | host_len = len + offset - host_offset; |
406 | a03e2d42 | bellard | host_len = HOST_PAGE_ALIGN(host_len); |
407 | a03e2d42 | bellard | mmap_start = mmap_find_vma(real_start, host_len); |
408 | a03e2d42 | bellard | if (mmap_start == (abi_ulong)-1) { |
409 | a03e2d42 | bellard | errno = ENOMEM; |
410 | c8a706fe | pbrook | goto fail;
|
411 | 54936004 | bellard | } |
412 | a03e2d42 | bellard | /* Note: we prefer to control the mapping address. It is
|
413 | a03e2d42 | bellard | especially important if qemu_host_page_size >
|
414 | a03e2d42 | bellard | qemu_real_host_page_size */
|
415 | a03e2d42 | bellard | p = mmap(g2h(mmap_start), |
416 | 54c5a2ae | edgar_igl | host_len, prot, flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0); |
417 | a03e2d42 | bellard | if (p == MAP_FAILED)
|
418 | c8a706fe | pbrook | goto fail;
|
419 | a03e2d42 | bellard | /* update start so that it points to the file position at 'offset' */
|
420 | a03e2d42 | bellard | host_start = (unsigned long)p; |
421 | 54c5a2ae | edgar_igl | if (!(flags & MAP_ANONYMOUS)) {
|
422 | 54c5a2ae | edgar_igl | p = mmap(g2h(mmap_start), len, prot, |
423 | 54c5a2ae | edgar_igl | flags | MAP_FIXED, fd, host_offset); |
424 | a03e2d42 | bellard | host_start += offset - host_offset; |
425 | 54c5a2ae | edgar_igl | } |
426 | a03e2d42 | bellard | start = h2g(host_start); |
427 | a03e2d42 | bellard | } else {
|
428 | 7ab240ad | balrog | int flg;
|
429 | 7ab240ad | balrog | target_ulong addr; |
430 | 7ab240ad | balrog | |
431 | a03e2d42 | bellard | if (start & ~TARGET_PAGE_MASK) {
|
432 | e89f07d3 | pbrook | errno = EINVAL; |
433 | c8a706fe | pbrook | goto fail;
|
434 | e89f07d3 | pbrook | } |
435 | a03e2d42 | bellard | end = start + len; |
436 | a03e2d42 | bellard | real_end = HOST_PAGE_ALIGN(end); |
437 | 7ab240ad | balrog | |
438 | 45bc1f52 | aurel32 | /*
|
439 | 45bc1f52 | aurel32 | * Test if requested memory area fits target address space
|
440 | 45bc1f52 | aurel32 | * It can fail only on 64-bit host with 32-bit target.
|
441 | 45bc1f52 | aurel32 | * On any other target/host host mmap() handles this error correctly.
|
442 | 45bc1f52 | aurel32 | */
|
443 | 45bc1f52 | aurel32 | if ((unsigned long)start + len - 1 > (abi_ulong) -1) { |
444 | 45bc1f52 | aurel32 | errno = EINVAL; |
445 | 45bc1f52 | aurel32 | goto fail;
|
446 | 45bc1f52 | aurel32 | } |
447 | 45bc1f52 | aurel32 | |
448 | 7ab240ad | balrog | for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
449 | 7ab240ad | balrog | flg = page_get_flags(addr); |
450 | 7ab240ad | balrog | if (flg & PAGE_RESERVED) {
|
451 | 7ab240ad | balrog | errno = ENXIO; |
452 | c8a706fe | pbrook | goto fail;
|
453 | 7ab240ad | balrog | } |
454 | 7ab240ad | balrog | } |
455 | 7ab240ad | balrog | |
456 | a03e2d42 | bellard | /* worst case: we cannot map the file because the offset is not
|
457 | a03e2d42 | bellard | aligned, so we read it */
|
458 | a03e2d42 | bellard | if (!(flags & MAP_ANONYMOUS) &&
|
459 | a03e2d42 | bellard | (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { |
460 | a03e2d42 | bellard | /* msync() won't work here, so we return an error if write is
|
461 | a03e2d42 | bellard | possible while it is a shared mapping */
|
462 | a03e2d42 | bellard | if ((flags & MAP_TYPE) == MAP_SHARED &&
|
463 | a03e2d42 | bellard | (prot & PROT_WRITE)) { |
464 | a03e2d42 | bellard | errno = EINVAL; |
465 | c8a706fe | pbrook | goto fail;
|
466 | a03e2d42 | bellard | } |
467 | a03e2d42 | bellard | retaddr = target_mmap(start, len, prot | PROT_WRITE, |
468 | a03e2d42 | bellard | MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, |
469 | a03e2d42 | bellard | -1, 0); |
470 | a03e2d42 | bellard | if (retaddr == -1) |
471 | c8a706fe | pbrook | goto fail;
|
472 | a03e2d42 | bellard | pread(fd, g2h(start), len, offset); |
473 | a03e2d42 | bellard | if (!(prot & PROT_WRITE)) {
|
474 | a03e2d42 | bellard | ret = target_mprotect(start, len, prot); |
475 | c8a706fe | pbrook | if (ret != 0) { |
476 | c8a706fe | pbrook | start = ret; |
477 | c8a706fe | pbrook | goto the_end;
|
478 | c8a706fe | pbrook | } |
479 | a03e2d42 | bellard | } |
480 | a03e2d42 | bellard | goto the_end;
|
481 | 54936004 | bellard | } |
482 | a03e2d42 | bellard | |
483 | a03e2d42 | bellard | /* handle the start of the mapping */
|
484 | a03e2d42 | bellard | if (start > real_start) {
|
485 | a03e2d42 | bellard | if (real_end == real_start + qemu_host_page_size) {
|
486 | a03e2d42 | bellard | /* one single host page */
|
487 | a03e2d42 | bellard | ret = mmap_frag(real_start, start, end, |
488 | a03e2d42 | bellard | prot, flags, fd, offset); |
489 | a03e2d42 | bellard | if (ret == -1) |
490 | c8a706fe | pbrook | goto fail;
|
491 | a03e2d42 | bellard | goto the_end1;
|
492 | a03e2d42 | bellard | } |
493 | a03e2d42 | bellard | ret = mmap_frag(real_start, start, real_start + qemu_host_page_size, |
494 | 54936004 | bellard | prot, flags, fd, offset); |
495 | 54936004 | bellard | if (ret == -1) |
496 | c8a706fe | pbrook | goto fail;
|
497 | a03e2d42 | bellard | real_start += qemu_host_page_size; |
498 | a03e2d42 | bellard | } |
499 | a03e2d42 | bellard | /* handle the end of the mapping */
|
500 | a03e2d42 | bellard | if (end < real_end) {
|
501 | a03e2d42 | bellard | ret = mmap_frag(real_end - qemu_host_page_size, |
502 | a03e2d42 | bellard | real_end - qemu_host_page_size, real_end, |
503 | a03e2d42 | bellard | prot, flags, fd, |
504 | a03e2d42 | bellard | offset + real_end - qemu_host_page_size - start); |
505 | a03e2d42 | bellard | if (ret == -1) |
506 | c8a706fe | pbrook | goto fail;
|
507 | a03e2d42 | bellard | real_end -= qemu_host_page_size; |
508 | 54936004 | bellard | } |
509 | 3b46e624 | ths | |
510 | a03e2d42 | bellard | /* map the middle (easier) */
|
511 | a03e2d42 | bellard | if (real_start < real_end) {
|
512 | a03e2d42 | bellard | void *p;
|
513 | a03e2d42 | bellard | unsigned long offset1; |
514 | a03e2d42 | bellard | if (flags & MAP_ANONYMOUS)
|
515 | a03e2d42 | bellard | offset1 = 0;
|
516 | a03e2d42 | bellard | else
|
517 | a03e2d42 | bellard | offset1 = offset + real_start - start; |
518 | a03e2d42 | bellard | p = mmap(g2h(real_start), real_end - real_start, |
519 | a03e2d42 | bellard | prot, flags, fd, offset1); |
520 | a03e2d42 | bellard | if (p == MAP_FAILED)
|
521 | c8a706fe | pbrook | goto fail;
|
522 | a03e2d42 | bellard | } |
523 | 54936004 | bellard | } |
524 | 54936004 | bellard | the_end1:
|
525 | 54936004 | bellard | page_set_flags(start, start + len, prot | PAGE_VALID); |
526 | 54936004 | bellard | the_end:
|
527 | 54936004 | bellard | #ifdef DEBUG_MMAP
|
528 | 2e0ded9c | edgar_igl | printf("ret=0x" TARGET_FMT_lx "\n", start); |
529 | 54936004 | bellard | page_dump(stdout); |
530 | 54936004 | bellard | printf("\n");
|
531 | 54936004 | bellard | #endif
|
532 | c8a706fe | pbrook | mmap_unlock(); |
533 | 54936004 | bellard | return start;
|
534 | c8a706fe | pbrook | fail:
|
535 | c8a706fe | pbrook | mmap_unlock(); |
536 | c8a706fe | pbrook | return -1; |
537 | 54936004 | bellard | } |
538 | 54936004 | bellard | |
539 | 992f48a0 | blueswir1 | int target_munmap(abi_ulong start, abi_ulong len)
|
540 | 54936004 | bellard | { |
541 | 992f48a0 | blueswir1 | abi_ulong end, real_start, real_end, addr; |
542 | 54936004 | bellard | int prot, ret;
|
543 | 54936004 | bellard | |
544 | 54936004 | bellard | #ifdef DEBUG_MMAP
|
545 | 54936004 | bellard | printf("munmap: start=0x%lx len=0x%lx\n", start, len);
|
546 | 54936004 | bellard | #endif
|
547 | 54936004 | bellard | if (start & ~TARGET_PAGE_MASK)
|
548 | 54936004 | bellard | return -EINVAL;
|
549 | 54936004 | bellard | len = TARGET_PAGE_ALIGN(len); |
550 | 54936004 | bellard | if (len == 0) |
551 | 54936004 | bellard | return -EINVAL;
|
552 | c8a706fe | pbrook | mmap_lock(); |
553 | 54936004 | bellard | end = start + len; |
554 | 53a5960a | pbrook | real_start = start & qemu_host_page_mask; |
555 | 53a5960a | pbrook | real_end = HOST_PAGE_ALIGN(end); |
556 | 54936004 | bellard | |
557 | 53a5960a | pbrook | if (start > real_start) {
|
558 | 54936004 | bellard | /* handle host page containing start */
|
559 | 54936004 | bellard | prot = 0;
|
560 | 53a5960a | pbrook | for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
|
561 | 54936004 | bellard | prot |= page_get_flags(addr); |
562 | 54936004 | bellard | } |
563 | 53a5960a | pbrook | if (real_end == real_start + qemu_host_page_size) {
|
564 | 53a5960a | pbrook | for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
565 | d418c81e | bellard | prot |= page_get_flags(addr); |
566 | d418c81e | bellard | } |
567 | 53a5960a | pbrook | end = real_end; |
568 | d418c81e | bellard | } |
569 | 54936004 | bellard | if (prot != 0) |
570 | 53a5960a | pbrook | real_start += qemu_host_page_size; |
571 | 54936004 | bellard | } |
572 | 53a5960a | pbrook | if (end < real_end) {
|
573 | 54936004 | bellard | prot = 0;
|
574 | 53a5960a | pbrook | for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
|
575 | 54936004 | bellard | prot |= page_get_flags(addr); |
576 | 54936004 | bellard | } |
577 | 54936004 | bellard | if (prot != 0) |
578 | 53a5960a | pbrook | real_end -= qemu_host_page_size; |
579 | 54936004 | bellard | } |
580 | 3b46e624 | ths | |
581 | c8a706fe | pbrook | ret = 0;
|
582 | 54936004 | bellard | /* unmap what we can */
|
583 | 53a5960a | pbrook | if (real_start < real_end) {
|
584 | 4118a970 | j_mayer | ret = munmap(g2h(real_start), real_end - real_start); |
585 | 54936004 | bellard | } |
586 | 54936004 | bellard | |
587 | c8a706fe | pbrook | if (ret == 0) |
588 | c8a706fe | pbrook | page_set_flags(start, start + len, 0);
|
589 | c8a706fe | pbrook | mmap_unlock(); |
590 | c8a706fe | pbrook | return ret;
|
591 | 54936004 | bellard | } |
592 | 54936004 | bellard | |
593 | 992f48a0 | blueswir1 | abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, |
594 | 992f48a0 | blueswir1 | abi_ulong new_size, unsigned long flags, |
595 | 992f48a0 | blueswir1 | abi_ulong new_addr) |
596 | 54936004 | bellard | { |
597 | 54936004 | bellard | int prot;
|
598 | f19412a2 | aurel32 | void *host_addr;
|
599 | 54936004 | bellard | |
600 | c8a706fe | pbrook | mmap_lock(); |
601 | f19412a2 | aurel32 | |
602 | f19412a2 | aurel32 | if (flags & MREMAP_FIXED)
|
603 | 3af72a4d | blueswir1 | host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
|
604 | 3af72a4d | blueswir1 | old_size, new_size, |
605 | 3af72a4d | blueswir1 | flags, |
606 | 3af72a4d | blueswir1 | new_addr); |
607 | f19412a2 | aurel32 | else if (flags & MREMAP_MAYMOVE) { |
608 | f19412a2 | aurel32 | abi_ulong mmap_start; |
609 | f19412a2 | aurel32 | |
610 | f19412a2 | aurel32 | mmap_start = mmap_find_vma(0, new_size);
|
611 | f19412a2 | aurel32 | |
612 | f19412a2 | aurel32 | if (mmap_start == -1) { |
613 | f19412a2 | aurel32 | errno = ENOMEM; |
614 | f19412a2 | aurel32 | host_addr = MAP_FAILED; |
615 | f19412a2 | aurel32 | } else
|
616 | 3af72a4d | blueswir1 | host_addr = (void *) syscall(__NR_mremap, g2h(old_addr),
|
617 | 3af72a4d | blueswir1 | old_size, new_size, |
618 | 3af72a4d | blueswir1 | flags | MREMAP_FIXED, |
619 | 3af72a4d | blueswir1 | g2h(mmap_start)); |
620 | 3af72a4d | blueswir1 | } else {
|
621 | f19412a2 | aurel32 | host_addr = mremap(g2h(old_addr), old_size, new_size, flags); |
622 | f19412a2 | aurel32 | /* Check if address fits target address space */
|
623 | f19412a2 | aurel32 | if ((unsigned long)host_addr + new_size > (abi_ulong)-1) { |
624 | f19412a2 | aurel32 | /* Revert mremap() changes */
|
625 | f19412a2 | aurel32 | host_addr = mremap(g2h(old_addr), new_size, old_size, flags); |
626 | f19412a2 | aurel32 | errno = ENOMEM; |
627 | f19412a2 | aurel32 | host_addr = MAP_FAILED; |
628 | f19412a2 | aurel32 | } |
629 | f19412a2 | aurel32 | } |
630 | f19412a2 | aurel32 | |
631 | f19412a2 | aurel32 | if (host_addr == MAP_FAILED) {
|
632 | c8a706fe | pbrook | new_addr = -1;
|
633 | c8a706fe | pbrook | } else {
|
634 | c8a706fe | pbrook | new_addr = h2g(host_addr); |
635 | c8a706fe | pbrook | prot = page_get_flags(old_addr); |
636 | c8a706fe | pbrook | page_set_flags(old_addr, old_addr + old_size, 0);
|
637 | c8a706fe | pbrook | page_set_flags(new_addr, new_addr + new_size, prot | PAGE_VALID); |
638 | c8a706fe | pbrook | } |
639 | c8a706fe | pbrook | mmap_unlock(); |
640 | 54936004 | bellard | return new_addr;
|
641 | 54936004 | bellard | } |
642 | 54936004 | bellard | |
643 | 992f48a0 | blueswir1 | int target_msync(abi_ulong start, abi_ulong len, int flags) |
644 | 54936004 | bellard | { |
645 | 992f48a0 | blueswir1 | abi_ulong end; |
646 | 54936004 | bellard | |
647 | 54936004 | bellard | if (start & ~TARGET_PAGE_MASK)
|
648 | 54936004 | bellard | return -EINVAL;
|
649 | 54936004 | bellard | len = TARGET_PAGE_ALIGN(len); |
650 | 54936004 | bellard | end = start + len; |
651 | d418c81e | bellard | if (end < start)
|
652 | d418c81e | bellard | return -EINVAL;
|
653 | d418c81e | bellard | if (end == start)
|
654 | d418c81e | bellard | return 0; |
655 | 3b46e624 | ths | |
656 | 83fb7adf | bellard | start &= qemu_host_page_mask; |
657 | 53a5960a | pbrook | return msync(g2h(start), end - start, flags);
|
658 | 54936004 | bellard | } |