1 /*
2 * memory management system call shims and definitions
3 *
4 * Copyright (c) 2013-15 Stacey D. Son
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 /*
21 * Copyright (c) 1982, 1986, 1993
22 * The Regents of the University of California. All rights reserved.
23 *
24 * Redistribution and use in source and binary forms, with or without
25 * modification, are permitted provided that the following conditions
26 * are met:
27 * 1. Redistributions of source code must retain the above copyright
28 * notice, this list of conditions and the following disclaimer.
29 * 2. Redistributions in binary form must reproduce the above copyright
30 * notice, this list of conditions and the following disclaimer in the
31 * documentation and/or other materials provided with the distribution.
32 * 4. Neither the name of the University nor the names of its contributors
33 * may be used to endorse or promote products derived from this software
34 * without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 */
48
49 #ifndef BSD_USER_BSD_MEM_H
50 #define BSD_USER_BSD_MEM_H
51
52 #include <sys/types.h>
53 #include <sys/ipc.h>
54 #include <sys/mman.h>
55 #include <sys/shm.h>
56 #include <fcntl.h>
57
58 #include "qemu-bsd.h"
59 #include "exec/page-protection.h"
60
61 extern struct bsd_shm_regions bsd_shm_regions[];
62 extern abi_ulong target_brk;
63 extern abi_ulong initial_target_brk;
64
65 /* mmap(2) */
do_bsd_mmap(void * cpu_env,abi_long arg1,abi_long arg2,abi_long arg3,abi_long arg4,abi_long arg5,abi_long arg6,abi_long arg7,abi_long arg8)66 static inline abi_long do_bsd_mmap(void *cpu_env, abi_long arg1, abi_long arg2,
67 abi_long arg3, abi_long arg4, abi_long arg5, abi_long arg6, abi_long arg7,
68 abi_long arg8)
69 {
70 if (regpairs_aligned(cpu_env) != 0) {
71 arg6 = arg7;
72 arg7 = arg8;
73 }
74 return get_errno(target_mmap(arg1, arg2, arg3,
75 target_to_host_bitmask(arg4, mmap_flags_tbl),
76 arg5, target_arg64(arg6, arg7)));
77 }
78
79 /* munmap(2) */
do_bsd_munmap(abi_long arg1,abi_long arg2)80 static inline abi_long do_bsd_munmap(abi_long arg1, abi_long arg2)
81 {
82 return get_errno(target_munmap(arg1, arg2));
83 }
84
85 /* mprotect(2) */
do_bsd_mprotect(abi_long arg1,abi_long arg2,abi_long arg3)86 static inline abi_long do_bsd_mprotect(abi_long arg1, abi_long arg2,
87 abi_long arg3)
88 {
89 return get_errno(target_mprotect(arg1, arg2, arg3));
90 }
91
92 /* msync(2) */
do_bsd_msync(abi_long addr,abi_long len,abi_long flags)93 static inline abi_long do_bsd_msync(abi_long addr, abi_long len, abi_long flags)
94 {
95 if (!guest_range_valid_untagged(addr, len)) {
96 /* It seems odd, but POSIX wants this to be ENOMEM */
97 return -TARGET_ENOMEM;
98 }
99
100 return get_errno(msync(g2h_untagged(addr), len, flags));
101 }
102
103 /* mlock(2) */
do_bsd_mlock(abi_long arg1,abi_long arg2)104 static inline abi_long do_bsd_mlock(abi_long arg1, abi_long arg2)
105 {
106 if (!guest_range_valid_untagged(arg1, arg2)) {
107 return -TARGET_EINVAL;
108 }
109 return get_errno(mlock(g2h_untagged(arg1), arg2));
110 }
111
112 /* munlock(2) */
do_bsd_munlock(abi_long arg1,abi_long arg2)113 static inline abi_long do_bsd_munlock(abi_long arg1, abi_long arg2)
114 {
115 if (!guest_range_valid_untagged(arg1, arg2)) {
116 return -TARGET_EINVAL;
117 }
118 return get_errno(munlock(g2h_untagged(arg1), arg2));
119 }
120
121 /* mlockall(2) */
do_bsd_mlockall(abi_long arg1)122 static inline abi_long do_bsd_mlockall(abi_long arg1)
123 {
124 return get_errno(mlockall(arg1));
125 }
126
127 /* munlockall(2) */
do_bsd_munlockall(void)128 static inline abi_long do_bsd_munlockall(void)
129 {
130 return get_errno(munlockall());
131 }
132
133 /* madvise(2) */
do_bsd_madvise(abi_long arg1,abi_long arg2,abi_long arg3)134 static inline abi_long do_bsd_madvise(abi_long arg1, abi_long arg2,
135 abi_long arg3)
136 {
137 abi_ulong len;
138 int ret = 0;
139 abi_long start = arg1;
140 abi_long len_in = arg2;
141 abi_long advice = arg3;
142
143 if (start & ~TARGET_PAGE_MASK) {
144 return -TARGET_EINVAL;
145 }
146 if (len_in == 0) {
147 return 0;
148 }
149 len = TARGET_PAGE_ALIGN(len_in);
150 if (len == 0 || !guest_range_valid_untagged(start, len)) {
151 return -TARGET_EINVAL;
152 }
153
154 /*
155 * Most advice values are hints, so ignoring and returning success is ok.
156 *
157 * However, some advice values such as MADV_DONTNEED, are not hints and
158 * need to be emulated.
159 *
160 * A straight passthrough for those may not be safe because qemu sometimes
161 * turns private file-backed mappings into anonymous mappings.
162 * If all guest pages have PAGE_PASSTHROUGH set, mappings have the
163 * same semantics for the host as for the guest.
164 *
165 * MADV_DONTNEED is passed through, if possible.
166 * If passthrough isn't possible, we nevertheless (wrongly!) return
167 * success, which is broken but some userspace programs fail to work
168 * otherwise. Completely implementing such emulation is quite complicated
169 * though.
170 */
171 mmap_lock();
172 switch (advice) {
173 case MADV_DONTNEED:
174 if (page_check_range(start, len, PAGE_PASSTHROUGH)) {
175 ret = get_errno(madvise(g2h_untagged(start), len, advice));
176 if (ret == 0) {
177 page_reset_target_data(start, start + len - 1);
178 }
179 }
180 }
181 mmap_unlock();
182
183 return ret;
184 }
185
186 /* minherit(2) */
do_bsd_minherit(abi_long addr,abi_long len,abi_long inherit)187 static inline abi_long do_bsd_minherit(abi_long addr, abi_long len,
188 abi_long inherit)
189 {
190 return get_errno(minherit(g2h_untagged(addr), len, inherit));
191 }
192
193 /* mincore(2) */
do_bsd_mincore(abi_ulong target_addr,abi_ulong len,abi_ulong target_vec)194 static inline abi_long do_bsd_mincore(abi_ulong target_addr, abi_ulong len,
195 abi_ulong target_vec)
196 {
197 abi_long ret;
198 void *p;
199 abi_ulong vec_len = DIV_ROUND_UP(len, TARGET_PAGE_SIZE);
200
201 if (!guest_range_valid_untagged(target_addr, len)
202 || !page_check_range(target_addr, len, PAGE_VALID)) {
203 return -TARGET_EFAULT;
204 }
205
206 p = lock_user(VERIFY_WRITE, target_vec, vec_len, 0);
207 if (p == NULL) {
208 return -TARGET_EFAULT;
209 }
210 ret = get_errno(mincore(g2h_untagged(target_addr), len, p));
211 unlock_user(p, target_vec, vec_len);
212
213 return ret;
214 }
215
216 /* do_brk() must return target values and target errnos. */
do_obreak(abi_ulong brk_val)217 static inline abi_long do_obreak(abi_ulong brk_val)
218 {
219 abi_long mapped_addr;
220 abi_ulong new_brk;
221 abi_ulong old_brk;
222
223 /* brk pointers are always untagged */
224
225 /* do not allow to shrink below initial brk value */
226 if (brk_val < initial_target_brk) {
227 return target_brk;
228 }
229
230 new_brk = TARGET_PAGE_ALIGN(brk_val);
231 old_brk = TARGET_PAGE_ALIGN(target_brk);
232
233 /* new and old target_brk might be on the same page */
234 if (new_brk == old_brk) {
235 target_brk = brk_val;
236 return target_brk;
237 }
238
239 /* Release heap if necessary */
240 if (new_brk < old_brk) {
241 target_munmap(new_brk, old_brk - new_brk);
242
243 target_brk = brk_val;
244 return target_brk;
245 }
246
247 mapped_addr = target_mmap(old_brk, new_brk - old_brk,
248 PROT_READ | PROT_WRITE,
249 MAP_FIXED | MAP_EXCL | MAP_ANON | MAP_PRIVATE,
250 -1, 0);
251
252 if (mapped_addr == old_brk) {
253 target_brk = brk_val;
254 return target_brk;
255 }
256
257 /* For everything else, return the previous break. */
258 return target_brk;
259 }
260
261 /* shm_open(2) */
do_bsd_shm_open(abi_ulong arg1,abi_long arg2,abi_long arg3)262 static inline abi_long do_bsd_shm_open(abi_ulong arg1, abi_long arg2,
263 abi_long arg3)
264 {
265 int ret;
266 void *p;
267
268 if (arg1 == (uintptr_t)SHM_ANON) {
269 p = SHM_ANON;
270 } else {
271 p = lock_user_string(arg1);
272 if (p == NULL) {
273 return -TARGET_EFAULT;
274 }
275 }
276 ret = get_errno(shm_open(p, target_to_host_bitmask(arg2, fcntl_flags_tbl),
277 arg3));
278
279 if (p != SHM_ANON) {
280 unlock_user(p, arg1, 0);
281 }
282
283 return ret;
284 }
285
286 /* shm_unlink(2) */
do_bsd_shm_unlink(abi_ulong arg1)287 static inline abi_long do_bsd_shm_unlink(abi_ulong arg1)
288 {
289 int ret;
290 void *p;
291
292 p = lock_user_string(arg1);
293 if (p == NULL) {
294 return -TARGET_EFAULT;
295 }
296 ret = get_errno(shm_unlink(p)); /* XXX path(p)? */
297 unlock_user(p, arg1, 0);
298
299 return ret;
300 }
301
302 /* shmget(2) */
do_bsd_shmget(abi_long arg1,abi_ulong arg2,abi_long arg3)303 static inline abi_long do_bsd_shmget(abi_long arg1, abi_ulong arg2,
304 abi_long arg3)
305 {
306 return get_errno(shmget(arg1, arg2, arg3));
307 }
308
309 /* shmctl(2) */
do_bsd_shmctl(abi_long shmid,abi_long cmd,abi_ulong buff)310 static inline abi_long do_bsd_shmctl(abi_long shmid, abi_long cmd,
311 abi_ulong buff)
312 {
313 struct shmid_ds dsarg;
314 abi_long ret = -TARGET_EINVAL;
315
316 cmd &= 0xff;
317
318 switch (cmd) {
319 case IPC_STAT:
320 if (target_to_host_shmid_ds(&dsarg, buff)) {
321 return -TARGET_EFAULT;
322 }
323 ret = get_errno(shmctl(shmid, cmd, &dsarg));
324 if (host_to_target_shmid_ds(buff, &dsarg)) {
325 return -TARGET_EFAULT;
326 }
327 break;
328
329 case IPC_SET:
330 if (target_to_host_shmid_ds(&dsarg, buff)) {
331 return -TARGET_EFAULT;
332 }
333 ret = get_errno(shmctl(shmid, cmd, &dsarg));
334 break;
335
336 case IPC_RMID:
337 ret = get_errno(shmctl(shmid, cmd, NULL));
338 break;
339
340 default:
341 ret = -TARGET_EINVAL;
342 break;
343 }
344
345 return ret;
346 }
347
348 /* shmat(2) */
do_bsd_shmat(int shmid,abi_ulong shmaddr,int shmflg)349 static inline abi_long do_bsd_shmat(int shmid, abi_ulong shmaddr, int shmflg)
350 {
351 abi_ulong raddr;
352 abi_long ret;
353 struct shmid_ds shm_info;
354
355 /* Find out the length of the shared memory segment. */
356 ret = get_errno(shmctl(shmid, IPC_STAT, &shm_info));
357 if (is_error(ret)) {
358 /* Can't get the length */
359 return ret;
360 }
361
362 if (!guest_range_valid_untagged(shmaddr, shm_info.shm_segsz)) {
363 return -TARGET_EINVAL;
364 }
365
366 WITH_MMAP_LOCK_GUARD() {
367 void *host_raddr;
368
369 if (shmaddr) {
370 host_raddr = shmat(shmid, (void *)g2h_untagged(shmaddr), shmflg);
371 } else {
372 abi_ulong mmap_start;
373
374 mmap_start = mmap_find_vma(0, shm_info.shm_segsz);
375
376 if (mmap_start == -1) {
377 return -TARGET_ENOMEM;
378 }
379 host_raddr = shmat(shmid, g2h_untagged(mmap_start),
380 shmflg | SHM_REMAP);
381 }
382
383 if (host_raddr == (void *)-1) {
384 return get_errno(-1);
385 }
386 raddr = h2g(host_raddr);
387
388 page_set_flags(raddr, raddr + shm_info.shm_segsz - 1,
389 PAGE_VALID | PAGE_RESET | PAGE_READ |
390 (shmflg & SHM_RDONLY ? 0 : PAGE_WRITE));
391
392 for (int i = 0; i < N_BSD_SHM_REGIONS; i++) {
393 if (bsd_shm_regions[i].start == 0) {
394 bsd_shm_regions[i].start = raddr;
395 bsd_shm_regions[i].size = shm_info.shm_segsz;
396 break;
397 }
398 }
399 }
400
401 return raddr;
402 }
403
404 /* shmdt(2) */
do_bsd_shmdt(abi_ulong shmaddr)405 static inline abi_long do_bsd_shmdt(abi_ulong shmaddr)
406 {
407 abi_long ret;
408
409 WITH_MMAP_LOCK_GUARD() {
410 int i;
411
412 for (i = 0; i < N_BSD_SHM_REGIONS; ++i) {
413 if (bsd_shm_regions[i].start == shmaddr) {
414 break;
415 }
416 }
417
418 if (i == N_BSD_SHM_REGIONS) {
419 return -TARGET_EINVAL;
420 }
421
422 ret = get_errno(shmdt(g2h_untagged(shmaddr)));
423 if (ret == 0) {
424 abi_ulong size = bsd_shm_regions[i].size;
425
426 bsd_shm_regions[i].start = 0;
427 page_set_flags(shmaddr, shmaddr + size - 1, 0);
428 mmap_reserve(shmaddr, size);
429 }
430 }
431
432 return ret;
433 }
434
do_bsd_vadvise(void)435 static inline abi_long do_bsd_vadvise(void)
436 {
437 /* See sys_ovadvise() in vm_unix.c */
438 return -TARGET_EINVAL;
439 }
440
do_bsd_sbrk(void)441 static inline abi_long do_bsd_sbrk(void)
442 {
443 /* see sys_sbrk() in vm_mmap.c */
444 return -TARGET_EOPNOTSUPP;
445 }
446
do_bsd_sstk(void)447 static inline abi_long do_bsd_sstk(void)
448 {
449 /* see sys_sstk() in vm_mmap.c */
450 return -TARGET_EOPNOTSUPP;
451 }
452
453 #endif /* BSD_USER_BSD_MEM_H */
454