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84778508 BS |
1 | /* |
2 | * mmap support for qemu | |
3 | * | |
4 | * Copyright (c) 2003 - 2008 Fabrice Bellard | |
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 | |
8167ee88 | 17 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
84778508 | 18 | */ |
2231197c | 19 | #include "qemu/osdep.h" |
84778508 BS |
20 | |
21 | #include "qemu.h" | |
22 | #include "qemu-common.h" | |
23 | ||
95992b67 | 24 | static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER; |
06943a62 | 25 | static __thread int mmap_lock_count; |
84778508 BS |
26 | |
27 | void mmap_lock(void) | |
28 | { | |
29 | if (mmap_lock_count++ == 0) { | |
30 | pthread_mutex_lock(&mmap_mutex); | |
31 | } | |
32 | } | |
33 | ||
34 | void mmap_unlock(void) | |
35 | { | |
36 | if (--mmap_lock_count == 0) { | |
37 | pthread_mutex_unlock(&mmap_mutex); | |
38 | } | |
39 | } | |
40 | ||
301e40ed AB |
41 | bool have_mmap_lock(void) |
42 | { | |
43 | return mmap_lock_count > 0 ? true : false; | |
44 | } | |
45 | ||
84778508 BS |
46 | /* Grab lock to make sure things are in a consistent state after fork(). */ |
47 | void mmap_fork_start(void) | |
48 | { | |
49 | if (mmap_lock_count) | |
50 | abort(); | |
51 | pthread_mutex_lock(&mmap_mutex); | |
52 | } | |
53 | ||
54 | void mmap_fork_end(int child) | |
55 | { | |
56 | if (child) | |
57 | pthread_mutex_init(&mmap_mutex, NULL); | |
58 | else | |
59 | pthread_mutex_unlock(&mmap_mutex); | |
60 | } | |
84778508 | 61 | |
84778508 BS |
62 | /* NOTE: all the constants are the HOST ones, but addresses are target. */ |
63 | int target_mprotect(abi_ulong start, abi_ulong len, int prot) | |
64 | { | |
65 | abi_ulong end, host_start, host_end, addr; | |
66 | int prot1, ret; | |
67 | ||
45b8765e WL |
68 | qemu_log_mask(CPU_LOG_PAGE, "mprotect: start=0x" TARGET_ABI_FMT_lx |
69 | " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c\n", start, len, | |
70 | prot & PROT_READ ? 'r' : '-', | |
71 | prot & PROT_WRITE ? 'w' : '-', | |
72 | prot & PROT_EXEC ? 'x' : '-'); | |
84778508 BS |
73 | if ((start & ~TARGET_PAGE_MASK) != 0) |
74 | return -EINVAL; | |
75 | len = TARGET_PAGE_ALIGN(len); | |
76 | end = start + len; | |
77 | if (end < start) | |
78 | return -EINVAL; | |
79 | prot &= PROT_READ | PROT_WRITE | PROT_EXEC; | |
80 | if (len == 0) | |
81 | return 0; | |
82 | ||
83 | mmap_lock(); | |
84 | host_start = start & qemu_host_page_mask; | |
85 | host_end = HOST_PAGE_ALIGN(end); | |
86 | if (start > host_start) { | |
87 | /* handle host page containing start */ | |
88 | prot1 = prot; | |
5be1d0b5 | 89 | for (addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
90 | prot1 |= page_get_flags(addr); |
91 | } | |
92 | if (host_end == host_start + qemu_host_page_size) { | |
5be1d0b5 | 93 | for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
94 | prot1 |= page_get_flags(addr); |
95 | } | |
96 | end = host_end; | |
97 | } | |
3e8f1628 RH |
98 | ret = mprotect(g2h_untagged(host_start), |
99 | qemu_host_page_size, prot1 & PAGE_BITS); | |
84778508 BS |
100 | if (ret != 0) |
101 | goto error; | |
102 | host_start += qemu_host_page_size; | |
103 | } | |
104 | if (end < host_end) { | |
105 | prot1 = prot; | |
5be1d0b5 | 106 | for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
107 | prot1 |= page_get_flags(addr); |
108 | } | |
3e8f1628 RH |
109 | ret = mprotect(g2h_untagged(host_end - qemu_host_page_size), |
110 | qemu_host_page_size, prot1 & PAGE_BITS); | |
84778508 BS |
111 | if (ret != 0) |
112 | goto error; | |
113 | host_end -= qemu_host_page_size; | |
114 | } | |
115 | ||
116 | /* handle the pages in the middle */ | |
117 | if (host_start < host_end) { | |
3e8f1628 | 118 | ret = mprotect(g2h_untagged(host_start), host_end - host_start, prot); |
84778508 BS |
119 | if (ret != 0) |
120 | goto error; | |
121 | } | |
122 | page_set_flags(start, start + len, prot | PAGE_VALID); | |
123 | mmap_unlock(); | |
124 | return 0; | |
125 | error: | |
126 | mmap_unlock(); | |
127 | return ret; | |
128 | } | |
129 | ||
a6b2d060 WL |
130 | /* |
131 | * map an incomplete host page | |
132 | * | |
133 | * mmap_frag can be called with a valid fd, if flags doesn't contain one of | |
134 | * MAP_ANON, MAP_STACK, MAP_GUARD. If we need to map a page in those cases, we | |
135 | * pass fd == -1. However, if flags contains MAP_GUARD then MAP_ANON cannot be | |
136 | * added. | |
137 | * | |
138 | * * If fd is valid (not -1) we want to map the pages with MAP_ANON. | |
139 | * * If flags contains MAP_GUARD we don't want to add MAP_ANON because it | |
140 | * will be rejected. See kern_mmap's enforcing of constraints for MAP_GUARD | |
141 | * in sys/vm/vm_mmap.c. | |
142 | * * If flags contains MAP_ANON it doesn't matter if we add it or not. | |
143 | * * If flags contains MAP_STACK, mmap adds MAP_ANON when called so doesn't | |
144 | * matter if we add it or not either. See enforcing of constraints for | |
145 | * MAP_STACK in kern_mmap. | |
146 | * | |
147 | * Don't add MAP_ANON for the flags that use fd == -1 without specifying the | |
148 | * flags directly, with the assumption that future flags that require fd == -1 | |
149 | * will also not require MAP_ANON. | |
150 | */ | |
84778508 BS |
151 | static int mmap_frag(abi_ulong real_start, |
152 | abi_ulong start, abi_ulong end, | |
153 | int prot, int flags, int fd, abi_ulong offset) | |
154 | { | |
155 | abi_ulong real_end, addr; | |
156 | void *host_start; | |
157 | int prot1, prot_new; | |
158 | ||
159 | real_end = real_start + qemu_host_page_size; | |
3e8f1628 | 160 | host_start = g2h_untagged(real_start); |
84778508 BS |
161 | |
162 | /* get the protection of the target pages outside the mapping */ | |
163 | prot1 = 0; | |
5be1d0b5 | 164 | for (addr = real_start; addr < real_end; addr++) { |
84778508 BS |
165 | if (addr < start || addr >= end) |
166 | prot1 |= page_get_flags(addr); | |
167 | } | |
168 | ||
169 | if (prot1 == 0) { | |
a6b2d060 | 170 | /* no page was there, so we allocate one. See also above. */ |
84778508 | 171 | void *p = mmap(host_start, qemu_host_page_size, prot, |
a6b2d060 | 172 | flags | ((fd != -1) ? MAP_ANON : 0), -1, 0); |
84778508 BS |
173 | if (p == MAP_FAILED) |
174 | return -1; | |
175 | prot1 = prot; | |
176 | } | |
177 | prot1 &= PAGE_BITS; | |
178 | ||
179 | prot_new = prot | prot1; | |
a6b2d060 | 180 | if (fd != -1) { |
84778508 BS |
181 | /* msync() won't work here, so we return an error if write is |
182 | possible while it is a shared mapping */ | |
6c173b3c | 183 | if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED && |
84778508 | 184 | (prot & PROT_WRITE)) |
059bca46 | 185 | return -1; |
84778508 BS |
186 | |
187 | /* adjust protection to be able to read */ | |
188 | if (!(prot1 & PROT_WRITE)) | |
189 | mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE); | |
190 | ||
191 | /* read the corresponding file data */ | |
26778ac3 MU |
192 | if (pread(fd, g2h_untagged(start), end - start, offset) == -1) { |
193 | return -1; | |
194 | } | |
84778508 BS |
195 | |
196 | /* put final protection */ | |
197 | if (prot_new != (prot1 | PROT_WRITE)) | |
198 | mprotect(host_start, qemu_host_page_size, prot_new); | |
199 | } else { | |
84778508 BS |
200 | if (prot_new != prot1) { |
201 | mprotect(host_start, qemu_host_page_size, prot_new); | |
202 | } | |
948516a3 MU |
203 | if (prot_new & PROT_WRITE) { |
204 | memset(g2h_untagged(start), 0, end - start); | |
205 | } | |
84778508 BS |
206 | } |
207 | return 0; | |
208 | } | |
209 | ||
be04f210 WL |
210 | #if HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64 |
211 | # define TASK_UNMAPPED_BASE (1ul << 38) | |
212 | #else | |
213 | # define TASK_UNMAPPED_BASE 0x40000000 | |
214 | #endif | |
215 | abi_ulong mmap_next_start = TASK_UNMAPPED_BASE; | |
84778508 BS |
216 | |
217 | unsigned long last_brk; | |
218 | ||
be04f210 WL |
219 | /* |
220 | * Subroutine of mmap_find_vma, used when we have pre-allocated a chunk of guest | |
221 | * address space. | |
222 | */ | |
223 | static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size, | |
224 | abi_ulong alignment) | |
84778508 | 225 | { |
be04f210 WL |
226 | abi_ulong addr; |
227 | abi_ulong end_addr; | |
84778508 | 228 | int prot; |
be04f210 WL |
229 | int looped = 0; |
230 | ||
231 | if (size > reserved_va) { | |
232 | return (abi_ulong)-1; | |
233 | } | |
234 | ||
235 | size = HOST_PAGE_ALIGN(size) + alignment; | |
236 | end_addr = start + size; | |
237 | if (end_addr > reserved_va) { | |
238 | end_addr = reserved_va; | |
239 | } | |
240 | addr = end_addr - qemu_host_page_size; | |
84778508 | 241 | |
be04f210 WL |
242 | while (1) { |
243 | if (addr > end_addr) { | |
244 | if (looped) { | |
245 | return (abi_ulong)-1; | |
246 | } | |
247 | end_addr = reserved_va; | |
248 | addr = end_addr - qemu_host_page_size; | |
249 | looped = 1; | |
250 | continue; | |
251 | } | |
252 | prot = page_get_flags(addr); | |
253 | if (prot) { | |
254 | end_addr = addr; | |
255 | } | |
256 | if (end_addr - addr >= size) { | |
257 | break; | |
258 | } | |
259 | addr -= qemu_host_page_size; | |
260 | } | |
261 | ||
262 | if (start == mmap_next_start) { | |
263 | mmap_next_start = addr; | |
264 | } | |
265 | /* addr is sufficiently low to align it up */ | |
266 | if (alignment != 0) { | |
267 | addr = (addr + alignment) & ~(alignment - 1); | |
268 | } | |
269 | return addr; | |
270 | } | |
271 | ||
272 | /* | |
273 | * Find and reserve a free memory area of size 'size'. The search | |
274 | * starts at 'start'. | |
275 | * It must be called with mmap_lock() held. | |
276 | * Return -1 if error. | |
277 | */ | |
278 | static abi_ulong mmap_find_vma_aligned(abi_ulong start, abi_ulong size, | |
279 | abi_ulong alignment) | |
280 | { | |
281 | void *ptr, *prev; | |
282 | abi_ulong addr; | |
283 | int flags; | |
284 | int wrapped, repeat; | |
285 | ||
286 | /* If 'start' == 0, then a default start address is used. */ | |
287 | if (start == 0) { | |
288 | start = mmap_next_start; | |
289 | } else { | |
290 | start &= qemu_host_page_mask; | |
84778508 | 291 | } |
84778508 BS |
292 | |
293 | size = HOST_PAGE_ALIGN(size); | |
be04f210 WL |
294 | |
295 | if (reserved_va) { | |
296 | return mmap_find_vma_reserved(start, size, | |
297 | (alignment != 0 ? 1 << alignment : 0)); | |
298 | } | |
299 | ||
84778508 | 300 | addr = start; |
be04f210 WL |
301 | wrapped = repeat = 0; |
302 | prev = 0; | |
953b69cc | 303 | flags = MAP_ANON | MAP_PRIVATE; |
be04f210 WL |
304 | if (alignment != 0) { |
305 | flags |= MAP_ALIGNED(alignment); | |
306 | } | |
be04f210 WL |
307 | |
308 | for (;; prev = ptr) { | |
309 | /* | |
310 | * Reserve needed memory area to avoid a race. | |
311 | * It should be discarded using: | |
312 | * - mmap() with MAP_FIXED flag | |
313 | * - mremap() with MREMAP_FIXED flag | |
314 | * - shmat() with SHM_REMAP flag | |
315 | */ | |
316 | ptr = mmap(g2h_untagged(addr), size, PROT_NONE, | |
317 | flags, -1, 0); | |
318 | ||
319 | /* ENOMEM, if host address space has no memory */ | |
320 | if (ptr == MAP_FAILED) { | |
321 | return (abi_ulong)-1; | |
84778508 | 322 | } |
be04f210 WL |
323 | |
324 | /* | |
325 | * Count the number of sequential returns of the same address. | |
326 | * This is used to modify the search algorithm below. | |
327 | */ | |
328 | repeat = (ptr == prev ? repeat + 1 : 0); | |
329 | ||
330 | if (h2g_valid(ptr + size - 1)) { | |
331 | addr = h2g(ptr); | |
332 | ||
333 | if ((addr & ~TARGET_PAGE_MASK) == 0) { | |
334 | /* Success. */ | |
335 | if (start == mmap_next_start && addr >= TASK_UNMAPPED_BASE) { | |
336 | mmap_next_start = addr + size; | |
337 | } | |
338 | return addr; | |
339 | } | |
340 | ||
341 | /* The address is not properly aligned for the target. */ | |
342 | switch (repeat) { | |
343 | case 0: | |
344 | /* | |
345 | * Assume the result that the kernel gave us is the | |
346 | * first with enough free space, so start again at the | |
347 | * next higher target page. | |
348 | */ | |
349 | addr = TARGET_PAGE_ALIGN(addr); | |
350 | break; | |
351 | case 1: | |
352 | /* | |
353 | * Sometimes the kernel decides to perform the allocation | |
354 | * at the top end of memory instead. | |
355 | */ | |
356 | addr &= TARGET_PAGE_MASK; | |
357 | break; | |
358 | case 2: | |
359 | /* Start over at low memory. */ | |
360 | addr = 0; | |
361 | break; | |
362 | default: | |
363 | /* Fail. This unaligned block must the last. */ | |
364 | addr = -1; | |
365 | break; | |
366 | } | |
367 | } else { | |
368 | /* | |
369 | * Since the result the kernel gave didn't fit, start | |
370 | * again at low memory. If any repetition, fail. | |
371 | */ | |
372 | addr = (repeat ? -1 : 0); | |
373 | } | |
374 | ||
375 | /* Unmap and try again. */ | |
376 | munmap(ptr, size); | |
377 | ||
378 | /* ENOMEM if we checked the whole of the target address space. */ | |
379 | if (addr == (abi_ulong)-1) { | |
380 | return (abi_ulong)-1; | |
381 | } else if (addr == 0) { | |
382 | if (wrapped) { | |
383 | return (abi_ulong)-1; | |
384 | } | |
385 | wrapped = 1; | |
386 | /* | |
387 | * Don't actually use 0 when wrapping, instead indicate | |
388 | * that we'd truly like an allocation in low memory. | |
389 | */ | |
390 | addr = TARGET_PAGE_SIZE; | |
391 | } else if (wrapped && addr >= start) { | |
84778508 | 392 | return (abi_ulong)-1; |
be04f210 | 393 | } |
84778508 | 394 | } |
be04f210 WL |
395 | } |
396 | ||
397 | abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size) | |
398 | { | |
399 | return mmap_find_vma_aligned(start, size, 0); | |
84778508 BS |
400 | } |
401 | ||
402 | /* NOTE: all the constants are the HOST ones */ | |
403 | abi_long target_mmap(abi_ulong start, abi_ulong len, int prot, | |
be04f210 | 404 | int flags, int fd, off_t offset) |
84778508 BS |
405 | { |
406 | abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len; | |
84778508 BS |
407 | |
408 | mmap_lock(); | |
45b8765e WL |
409 | if (qemu_loglevel_mask(CPU_LOG_PAGE)) { |
410 | qemu_log("mmap: start=0x" TARGET_ABI_FMT_lx | |
411 | " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=", | |
412 | start, len, | |
413 | prot & PROT_READ ? 'r' : '-', | |
414 | prot & PROT_WRITE ? 'w' : '-', | |
415 | prot & PROT_EXEC ? 'x' : '-'); | |
6a3b9bfd | 416 | if (flags & MAP_ALIGNMENT_MASK) { |
45b8765e WL |
417 | qemu_log("MAP_ALIGNED(%u) ", |
418 | (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT); | |
6a3b9bfd | 419 | } |
6a3b9bfd | 420 | if (flags & MAP_GUARD) { |
45b8765e | 421 | qemu_log("MAP_GUARD "); |
6a3b9bfd | 422 | } |
6a3b9bfd | 423 | if (flags & MAP_FIXED) { |
45b8765e | 424 | qemu_log("MAP_FIXED "); |
6a3b9bfd | 425 | } |
953b69cc | 426 | if (flags & MAP_ANON) { |
45b8765e | 427 | qemu_log("MAP_ANON "); |
6a3b9bfd | 428 | } |
6a3b9bfd | 429 | if (flags & MAP_EXCL) { |
45b8765e | 430 | qemu_log("MAP_EXCL "); |
6a3b9bfd | 431 | } |
6a3b9bfd | 432 | if (flags & MAP_PRIVATE) { |
45b8765e | 433 | qemu_log("MAP_PRIVATE "); |
6a3b9bfd WL |
434 | } |
435 | if (flags & MAP_SHARED) { | |
45b8765e | 436 | qemu_log("MAP_SHARED "); |
84778508 | 437 | } |
6a3b9bfd | 438 | if (flags & MAP_NOCORE) { |
45b8765e | 439 | qemu_log("MAP_NOCORE "); |
6a3b9bfd | 440 | } |
6a3b9bfd | 441 | if (flags & MAP_STACK) { |
45b8765e | 442 | qemu_log("MAP_STACK "); |
6a3b9bfd | 443 | } |
45b8765e | 444 | qemu_log("fd=%d offset=0x%lx\n", fd, offset); |
84778508 | 445 | } |
84778508 | 446 | |
953b69cc | 447 | if ((flags & MAP_ANON) && fd != -1) { |
be04f210 WL |
448 | errno = EINVAL; |
449 | goto fail; | |
450 | } | |
be04f210 WL |
451 | if (flags & MAP_STACK) { |
452 | if ((fd != -1) || ((prot & (PROT_READ | PROT_WRITE)) != | |
453 | (PROT_READ | PROT_WRITE))) { | |
454 | errno = EINVAL; | |
455 | goto fail; | |
456 | } | |
457 | } | |
be04f210 WL |
458 | if ((flags & MAP_GUARD) && (prot != PROT_NONE || fd != -1 || |
459 | offset != 0 || (flags & (MAP_SHARED | MAP_PRIVATE | | |
460 | /* MAP_PREFAULT | */ /* MAP_PREFAULT not in mman.h */ | |
461 | MAP_PREFAULT_READ | MAP_ANON | MAP_STACK)) != 0)) { | |
462 | errno = EINVAL; | |
463 | goto fail; | |
464 | } | |
be04f210 | 465 | |
84778508 BS |
466 | if (offset & ~TARGET_PAGE_MASK) { |
467 | errno = EINVAL; | |
468 | goto fail; | |
469 | } | |
470 | ||
be04f210 WL |
471 | if (len == 0) { |
472 | errno = EINVAL; | |
473 | goto fail; | |
474 | } | |
14837a3f WL |
475 | |
476 | /* Check for overflows */ | |
477 | len = TARGET_PAGE_ALIGN(len); | |
478 | if (len == 0) { | |
479 | errno = ENOMEM; | |
480 | goto fail; | |
481 | } | |
482 | ||
84778508 | 483 | real_start = start & qemu_host_page_mask; |
be04f210 | 484 | host_offset = offset & qemu_host_page_mask; |
84778508 | 485 | |
be04f210 WL |
486 | /* |
487 | * If the user is asking for the kernel to find a location, do that | |
488 | * before we truncate the length for mapping files below. | |
489 | */ | |
84778508 | 490 | if (!(flags & MAP_FIXED)) { |
84778508 BS |
491 | host_len = len + offset - host_offset; |
492 | host_len = HOST_PAGE_ALIGN(host_len); | |
be04f210 WL |
493 | if ((flags & MAP_ALIGNMENT_MASK) != 0) |
494 | start = mmap_find_vma_aligned(real_start, host_len, | |
495 | (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT); | |
496 | else | |
497 | start = mmap_find_vma(real_start, host_len); | |
498 | if (start == (abi_ulong)-1) { | |
84778508 BS |
499 | errno = ENOMEM; |
500 | goto fail; | |
501 | } | |
be04f210 WL |
502 | } |
503 | ||
504 | /* | |
505 | * When mapping files into a memory area larger than the file, accesses | |
506 | * to pages beyond the file size will cause a SIGBUS. | |
507 | * | |
508 | * For example, if mmaping a file of 100 bytes on a host with 4K pages | |
509 | * emulating a target with 8K pages, the target expects to be able to | |
510 | * access the first 8K. But the host will trap us on any access beyond | |
511 | * 4K. | |
512 | * | |
513 | * When emulating a target with a larger page-size than the hosts, we | |
514 | * may need to truncate file maps at EOF and add extra anonymous pages | |
515 | * up to the targets page boundary. | |
516 | */ | |
517 | ||
518 | if ((qemu_real_host_page_size < qemu_host_page_size) && fd != -1) { | |
519 | struct stat sb; | |
520 | ||
521 | if (fstat(fd, &sb) == -1) { | |
522 | goto fail; | |
523 | } | |
524 | ||
525 | /* Are we trying to create a map beyond EOF?. */ | |
526 | if (offset + len > sb.st_size) { | |
527 | /* | |
528 | * If so, truncate the file map at eof aligned with | |
529 | * the hosts real pagesize. Additional anonymous maps | |
530 | * will be created beyond EOF. | |
531 | */ | |
532 | len = REAL_HOST_PAGE_ALIGN(sb.st_size - offset); | |
533 | } | |
534 | } | |
535 | ||
536 | if (!(flags & MAP_FIXED)) { | |
537 | unsigned long host_start; | |
538 | void *p; | |
539 | ||
540 | host_len = len + offset - host_offset; | |
541 | host_len = HOST_PAGE_ALIGN(host_len); | |
542 | ||
543 | /* | |
544 | * Note: we prefer to control the mapping address. It is | |
545 | * especially important if qemu_host_page_size > | |
546 | * qemu_real_host_page_size | |
547 | */ | |
548 | p = mmap(g2h_untagged(start), host_len, prot, | |
953b69cc | 549 | flags | MAP_FIXED | ((fd != -1) ? MAP_ANON : 0), -1, 0); |
84778508 BS |
550 | if (p == MAP_FAILED) |
551 | goto fail; | |
552 | /* update start so that it points to the file position at 'offset' */ | |
553 | host_start = (unsigned long)p; | |
be04f210 WL |
554 | if (fd != -1) { |
555 | p = mmap(g2h_untagged(start), len, prot, | |
556 | flags | MAP_FIXED, fd, host_offset); | |
557 | if (p == MAP_FAILED) { | |
558 | munmap(g2h_untagged(start), host_len); | |
559 | goto fail; | |
560 | } | |
84778508 | 561 | host_start += offset - host_offset; |
be04f210 | 562 | } |
84778508 BS |
563 | start = h2g(host_start); |
564 | } else { | |
84778508 BS |
565 | if (start & ~TARGET_PAGE_MASK) { |
566 | errno = EINVAL; | |
567 | goto fail; | |
568 | } | |
569 | end = start + len; | |
570 | real_end = HOST_PAGE_ALIGN(end); | |
571 | ||
be04f210 WL |
572 | /* |
573 | * Test if requested memory area fits target address space | |
574 | * It can fail only on 64-bit host with 32-bit target. | |
575 | * On any other target/host host mmap() handles this error correctly. | |
576 | */ | |
0fc76b68 | 577 | if (!guest_range_valid_untagged(start, len)) { |
be04f210 WL |
578 | errno = EINVAL; |
579 | goto fail; | |
84778508 BS |
580 | } |
581 | ||
be04f210 WL |
582 | /* |
583 | * worst case: we cannot map the file because the offset is not | |
584 | * aligned, so we read it | |
585 | */ | |
a6b2d060 | 586 | if (fd != -1 && |
84778508 | 587 | (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { |
be04f210 WL |
588 | /* |
589 | * msync() won't work here, so we return an error if write is | |
590 | * possible while it is a shared mapping | |
591 | */ | |
6c173b3c | 592 | if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED && |
84778508 BS |
593 | (prot & PROT_WRITE)) { |
594 | errno = EINVAL; | |
595 | goto fail; | |
596 | } | |
597 | retaddr = target_mmap(start, len, prot | PROT_WRITE, | |
598 | MAP_FIXED | MAP_PRIVATE | MAP_ANON, | |
599 | -1, 0); | |
600 | if (retaddr == -1) | |
601 | goto fail; | |
26778ac3 MU |
602 | if (pread(fd, g2h_untagged(start), len, offset) == -1) { |
603 | goto fail; | |
604 | } | |
84778508 BS |
605 | if (!(prot & PROT_WRITE)) { |
606 | ret = target_mprotect(start, len, prot); | |
91a5adda | 607 | assert(ret == 0); |
84778508 BS |
608 | } |
609 | goto the_end; | |
610 | } | |
611 | ||
0fc76b68 KE |
612 | /* Reject the mapping if any page within the range is mapped */ |
613 | if ((flags & MAP_EXCL) && page_check_range(start, len, 0) < 0) { | |
614 | errno = EINVAL; | |
615 | goto fail; | |
616 | } | |
617 | ||
84778508 BS |
618 | /* handle the start of the mapping */ |
619 | if (start > real_start) { | |
620 | if (real_end == real_start + qemu_host_page_size) { | |
621 | /* one single host page */ | |
622 | ret = mmap_frag(real_start, start, end, | |
623 | prot, flags, fd, offset); | |
624 | if (ret == -1) | |
625 | goto fail; | |
626 | goto the_end1; | |
627 | } | |
628 | ret = mmap_frag(real_start, start, real_start + qemu_host_page_size, | |
629 | prot, flags, fd, offset); | |
630 | if (ret == -1) | |
631 | goto fail; | |
632 | real_start += qemu_host_page_size; | |
633 | } | |
634 | /* handle the end of the mapping */ | |
635 | if (end < real_end) { | |
636 | ret = mmap_frag(real_end - qemu_host_page_size, | |
be04f210 | 637 | real_end - qemu_host_page_size, end, |
84778508 BS |
638 | prot, flags, fd, |
639 | offset + real_end - qemu_host_page_size - start); | |
640 | if (ret == -1) | |
641 | goto fail; | |
642 | real_end -= qemu_host_page_size; | |
643 | } | |
644 | ||
645 | /* map the middle (easier) */ | |
646 | if (real_start < real_end) { | |
647 | void *p; | |
648 | unsigned long offset1; | |
649 | if (flags & MAP_ANON) | |
650 | offset1 = 0; | |
651 | else | |
652 | offset1 = offset + real_start - start; | |
3e8f1628 | 653 | p = mmap(g2h_untagged(real_start), real_end - real_start, |
84778508 BS |
654 | prot, flags, fd, offset1); |
655 | if (p == MAP_FAILED) | |
656 | goto fail; | |
657 | } | |
658 | } | |
659 | the_end1: | |
660 | page_set_flags(start, start + len, prot | PAGE_VALID); | |
661 | the_end: | |
662 | #ifdef DEBUG_MMAP | |
6a3b9bfd | 663 | printf("ret=0x" TARGET_ABI_FMT_lx "\n", start); |
84778508 BS |
664 | page_dump(stdout); |
665 | printf("\n"); | |
666 | #endif | |
be04f210 | 667 | tb_invalidate_phys_range(start, start + len); |
84778508 BS |
668 | mmap_unlock(); |
669 | return start; | |
670 | fail: | |
671 | mmap_unlock(); | |
672 | return -1; | |
673 | } | |
674 | ||
be04f210 WL |
675 | static void mmap_reserve(abi_ulong start, abi_ulong size) |
676 | { | |
677 | abi_ulong real_start; | |
678 | abi_ulong real_end; | |
679 | abi_ulong addr; | |
680 | abi_ulong end; | |
681 | int prot; | |
682 | ||
683 | real_start = start & qemu_host_page_mask; | |
684 | real_end = HOST_PAGE_ALIGN(start + size); | |
685 | end = start + size; | |
686 | if (start > real_start) { | |
687 | /* handle host page containing start */ | |
688 | prot = 0; | |
689 | for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) { | |
690 | prot |= page_get_flags(addr); | |
691 | } | |
692 | if (real_end == real_start + qemu_host_page_size) { | |
693 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { | |
694 | prot |= page_get_flags(addr); | |
695 | } | |
696 | end = real_end; | |
697 | } | |
698 | if (prot != 0) { | |
699 | real_start += qemu_host_page_size; | |
700 | } | |
701 | } | |
702 | if (end < real_end) { | |
703 | prot = 0; | |
704 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { | |
705 | prot |= page_get_flags(addr); | |
706 | } | |
707 | if (prot != 0) { | |
708 | real_end -= qemu_host_page_size; | |
709 | } | |
710 | } | |
711 | if (real_start != real_end) { | |
712 | mmap(g2h_untagged(real_start), real_end - real_start, PROT_NONE, | |
953b69cc | 713 | MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0); |
be04f210 WL |
714 | } |
715 | } | |
716 | ||
84778508 BS |
717 | int target_munmap(abi_ulong start, abi_ulong len) |
718 | { | |
719 | abi_ulong end, real_start, real_end, addr; | |
720 | int prot, ret; | |
721 | ||
722 | #ifdef DEBUG_MMAP | |
6a3b9bfd WL |
723 | printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x" |
724 | TARGET_ABI_FMT_lx "\n", | |
725 | start, len); | |
84778508 BS |
726 | #endif |
727 | if (start & ~TARGET_PAGE_MASK) | |
728 | return -EINVAL; | |
729 | len = TARGET_PAGE_ALIGN(len); | |
730 | if (len == 0) | |
731 | return -EINVAL; | |
732 | mmap_lock(); | |
733 | end = start + len; | |
734 | real_start = start & qemu_host_page_mask; | |
735 | real_end = HOST_PAGE_ALIGN(end); | |
736 | ||
737 | if (start > real_start) { | |
738 | /* handle host page containing start */ | |
739 | prot = 0; | |
5be1d0b5 | 740 | for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
741 | prot |= page_get_flags(addr); |
742 | } | |
743 | if (real_end == real_start + qemu_host_page_size) { | |
5be1d0b5 | 744 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
745 | prot |= page_get_flags(addr); |
746 | } | |
747 | end = real_end; | |
748 | } | |
749 | if (prot != 0) | |
750 | real_start += qemu_host_page_size; | |
751 | } | |
752 | if (end < real_end) { | |
753 | prot = 0; | |
5be1d0b5 | 754 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
755 | prot |= page_get_flags(addr); |
756 | } | |
757 | if (prot != 0) | |
758 | real_end -= qemu_host_page_size; | |
759 | } | |
760 | ||
761 | ret = 0; | |
762 | /* unmap what we can */ | |
763 | if (real_start < real_end) { | |
be04f210 WL |
764 | if (reserved_va) { |
765 | mmap_reserve(real_start, real_end - real_start); | |
766 | } else { | |
767 | ret = munmap(g2h_untagged(real_start), real_end - real_start); | |
768 | } | |
84778508 BS |
769 | } |
770 | ||
be04f210 | 771 | if (ret == 0) { |
84778508 | 772 | page_set_flags(start, start + len, 0); |
be04f210 WL |
773 | tb_invalidate_phys_range(start, start + len); |
774 | } | |
84778508 BS |
775 | mmap_unlock(); |
776 | return ret; | |
777 | } | |
778 | ||
779 | int target_msync(abi_ulong start, abi_ulong len, int flags) | |
780 | { | |
781 | abi_ulong end; | |
782 | ||
783 | if (start & ~TARGET_PAGE_MASK) | |
784 | return -EINVAL; | |
785 | len = TARGET_PAGE_ALIGN(len); | |
786 | end = start + len; | |
787 | if (end < start) | |
788 | return -EINVAL; | |
789 | if (end == start) | |
790 | return 0; | |
791 | ||
792 | start &= qemu_host_page_mask; | |
3e8f1628 | 793 | return msync(g2h_untagged(start), end - start, flags); |
84778508 | 794 | } |