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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" | |
84778508 | 22 | |
95992b67 | 23 | static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER; |
06943a62 | 24 | static __thread int mmap_lock_count; |
84778508 BS |
25 | |
26 | void mmap_lock(void) | |
27 | { | |
28 | if (mmap_lock_count++ == 0) { | |
29 | pthread_mutex_lock(&mmap_mutex); | |
30 | } | |
31 | } | |
32 | ||
33 | void mmap_unlock(void) | |
34 | { | |
35 | if (--mmap_lock_count == 0) { | |
36 | pthread_mutex_unlock(&mmap_mutex); | |
37 | } | |
38 | } | |
39 | ||
301e40ed AB |
40 | bool have_mmap_lock(void) |
41 | { | |
42 | return mmap_lock_count > 0 ? true : false; | |
43 | } | |
44 | ||
84778508 BS |
45 | /* Grab lock to make sure things are in a consistent state after fork(). */ |
46 | void mmap_fork_start(void) | |
47 | { | |
48 | if (mmap_lock_count) | |
49 | abort(); | |
50 | pthread_mutex_lock(&mmap_mutex); | |
51 | } | |
52 | ||
53 | void mmap_fork_end(int child) | |
54 | { | |
55 | if (child) | |
56 | pthread_mutex_init(&mmap_mutex, NULL); | |
57 | else | |
58 | pthread_mutex_unlock(&mmap_mutex); | |
59 | } | |
84778508 | 60 | |
84778508 BS |
61 | /* NOTE: all the constants are the HOST ones, but addresses are target. */ |
62 | int target_mprotect(abi_ulong start, abi_ulong len, int prot) | |
63 | { | |
64 | abi_ulong end, host_start, host_end, addr; | |
65 | int prot1, ret; | |
66 | ||
45b8765e WL |
67 | qemu_log_mask(CPU_LOG_PAGE, "mprotect: start=0x" TARGET_ABI_FMT_lx |
68 | " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c\n", start, len, | |
69 | prot & PROT_READ ? 'r' : '-', | |
70 | prot & PROT_WRITE ? 'w' : '-', | |
71 | prot & PROT_EXEC ? 'x' : '-'); | |
84778508 BS |
72 | if ((start & ~TARGET_PAGE_MASK) != 0) |
73 | return -EINVAL; | |
74 | len = TARGET_PAGE_ALIGN(len); | |
75 | end = start + len; | |
76 | if (end < start) | |
77 | return -EINVAL; | |
78 | prot &= PROT_READ | PROT_WRITE | PROT_EXEC; | |
79 | if (len == 0) | |
80 | return 0; | |
81 | ||
82 | mmap_lock(); | |
83 | host_start = start & qemu_host_page_mask; | |
84 | host_end = HOST_PAGE_ALIGN(end); | |
85 | if (start > host_start) { | |
86 | /* handle host page containing start */ | |
87 | prot1 = prot; | |
5be1d0b5 | 88 | for (addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
89 | prot1 |= page_get_flags(addr); |
90 | } | |
91 | if (host_end == host_start + qemu_host_page_size) { | |
5be1d0b5 | 92 | for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
93 | prot1 |= page_get_flags(addr); |
94 | } | |
95 | end = host_end; | |
96 | } | |
3e8f1628 RH |
97 | ret = mprotect(g2h_untagged(host_start), |
98 | qemu_host_page_size, prot1 & PAGE_BITS); | |
84778508 BS |
99 | if (ret != 0) |
100 | goto error; | |
101 | host_start += qemu_host_page_size; | |
102 | } | |
103 | if (end < host_end) { | |
104 | prot1 = prot; | |
5be1d0b5 | 105 | for (addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
106 | prot1 |= page_get_flags(addr); |
107 | } | |
3e8f1628 RH |
108 | ret = mprotect(g2h_untagged(host_end - qemu_host_page_size), |
109 | qemu_host_page_size, prot1 & PAGE_BITS); | |
84778508 BS |
110 | if (ret != 0) |
111 | goto error; | |
112 | host_end -= qemu_host_page_size; | |
113 | } | |
114 | ||
115 | /* handle the pages in the middle */ | |
116 | if (host_start < host_end) { | |
3e8f1628 | 117 | ret = mprotect(g2h_untagged(host_start), host_end - host_start, prot); |
84778508 BS |
118 | if (ret != 0) |
119 | goto error; | |
120 | } | |
121 | page_set_flags(start, start + len, prot | PAGE_VALID); | |
122 | mmap_unlock(); | |
123 | return 0; | |
124 | error: | |
125 | mmap_unlock(); | |
126 | return ret; | |
127 | } | |
128 | ||
a6b2d060 WL |
129 | /* |
130 | * map an incomplete host page | |
131 | * | |
132 | * mmap_frag can be called with a valid fd, if flags doesn't contain one of | |
133 | * MAP_ANON, MAP_STACK, MAP_GUARD. If we need to map a page in those cases, we | |
134 | * pass fd == -1. However, if flags contains MAP_GUARD then MAP_ANON cannot be | |
135 | * added. | |
136 | * | |
137 | * * If fd is valid (not -1) we want to map the pages with MAP_ANON. | |
138 | * * If flags contains MAP_GUARD we don't want to add MAP_ANON because it | |
139 | * will be rejected. See kern_mmap's enforcing of constraints for MAP_GUARD | |
140 | * in sys/vm/vm_mmap.c. | |
141 | * * If flags contains MAP_ANON it doesn't matter if we add it or not. | |
142 | * * If flags contains MAP_STACK, mmap adds MAP_ANON when called so doesn't | |
143 | * matter if we add it or not either. See enforcing of constraints for | |
144 | * MAP_STACK in kern_mmap. | |
145 | * | |
146 | * Don't add MAP_ANON for the flags that use fd == -1 without specifying the | |
147 | * flags directly, with the assumption that future flags that require fd == -1 | |
148 | * will also not require MAP_ANON. | |
149 | */ | |
84778508 BS |
150 | static int mmap_frag(abi_ulong real_start, |
151 | abi_ulong start, abi_ulong end, | |
152 | int prot, int flags, int fd, abi_ulong offset) | |
153 | { | |
154 | abi_ulong real_end, addr; | |
155 | void *host_start; | |
156 | int prot1, prot_new; | |
157 | ||
158 | real_end = real_start + qemu_host_page_size; | |
3e8f1628 | 159 | host_start = g2h_untagged(real_start); |
84778508 BS |
160 | |
161 | /* get the protection of the target pages outside the mapping */ | |
162 | prot1 = 0; | |
5be1d0b5 | 163 | for (addr = real_start; addr < real_end; addr++) { |
84778508 BS |
164 | if (addr < start || addr >= end) |
165 | prot1 |= page_get_flags(addr); | |
166 | } | |
167 | ||
168 | if (prot1 == 0) { | |
a6b2d060 | 169 | /* no page was there, so we allocate one. See also above. */ |
84778508 | 170 | void *p = mmap(host_start, qemu_host_page_size, prot, |
a6b2d060 | 171 | flags | ((fd != -1) ? MAP_ANON : 0), -1, 0); |
84778508 BS |
172 | if (p == MAP_FAILED) |
173 | return -1; | |
174 | prot1 = prot; | |
175 | } | |
176 | prot1 &= PAGE_BITS; | |
177 | ||
178 | prot_new = prot | prot1; | |
a6b2d060 | 179 | if (fd != -1) { |
84778508 BS |
180 | /* msync() won't work here, so we return an error if write is |
181 | possible while it is a shared mapping */ | |
6c173b3c | 182 | if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED && |
84778508 | 183 | (prot & PROT_WRITE)) |
059bca46 | 184 | return -1; |
84778508 BS |
185 | |
186 | /* adjust protection to be able to read */ | |
187 | if (!(prot1 & PROT_WRITE)) | |
188 | mprotect(host_start, qemu_host_page_size, prot1 | PROT_WRITE); | |
189 | ||
190 | /* read the corresponding file data */ | |
26778ac3 MU |
191 | if (pread(fd, g2h_untagged(start), end - start, offset) == -1) { |
192 | return -1; | |
193 | } | |
84778508 BS |
194 | |
195 | /* put final protection */ | |
196 | if (prot_new != (prot1 | PROT_WRITE)) | |
197 | mprotect(host_start, qemu_host_page_size, prot_new); | |
198 | } else { | |
84778508 BS |
199 | if (prot_new != prot1) { |
200 | mprotect(host_start, qemu_host_page_size, prot_new); | |
201 | } | |
948516a3 MU |
202 | if (prot_new & PROT_WRITE) { |
203 | memset(g2h_untagged(start), 0, end - start); | |
204 | } | |
84778508 BS |
205 | } |
206 | return 0; | |
207 | } | |
208 | ||
be04f210 WL |
209 | #if HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64 |
210 | # define TASK_UNMAPPED_BASE (1ul << 38) | |
211 | #else | |
212 | # define TASK_UNMAPPED_BASE 0x40000000 | |
213 | #endif | |
214 | abi_ulong mmap_next_start = TASK_UNMAPPED_BASE; | |
84778508 BS |
215 | |
216 | unsigned long last_brk; | |
217 | ||
be04f210 WL |
218 | /* |
219 | * Subroutine of mmap_find_vma, used when we have pre-allocated a chunk of guest | |
220 | * address space. | |
221 | */ | |
222 | static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size, | |
223 | abi_ulong alignment) | |
84778508 | 224 | { |
be04f210 WL |
225 | abi_ulong addr; |
226 | abi_ulong end_addr; | |
84778508 | 227 | int prot; |
be04f210 WL |
228 | int looped = 0; |
229 | ||
230 | if (size > reserved_va) { | |
231 | return (abi_ulong)-1; | |
232 | } | |
233 | ||
234 | size = HOST_PAGE_ALIGN(size) + alignment; | |
235 | end_addr = start + size; | |
236 | if (end_addr > reserved_va) { | |
237 | end_addr = reserved_va; | |
238 | } | |
239 | addr = end_addr - qemu_host_page_size; | |
84778508 | 240 | |
be04f210 WL |
241 | while (1) { |
242 | if (addr > end_addr) { | |
243 | if (looped) { | |
244 | return (abi_ulong)-1; | |
245 | } | |
246 | end_addr = reserved_va; | |
247 | addr = end_addr - qemu_host_page_size; | |
248 | looped = 1; | |
249 | continue; | |
250 | } | |
251 | prot = page_get_flags(addr); | |
252 | if (prot) { | |
253 | end_addr = addr; | |
254 | } | |
255 | if (end_addr - addr >= size) { | |
256 | break; | |
257 | } | |
258 | addr -= qemu_host_page_size; | |
259 | } | |
260 | ||
261 | if (start == mmap_next_start) { | |
262 | mmap_next_start = addr; | |
263 | } | |
264 | /* addr is sufficiently low to align it up */ | |
265 | if (alignment != 0) { | |
266 | addr = (addr + alignment) & ~(alignment - 1); | |
267 | } | |
268 | return addr; | |
269 | } | |
270 | ||
271 | /* | |
272 | * Find and reserve a free memory area of size 'size'. The search | |
273 | * starts at 'start'. | |
274 | * It must be called with mmap_lock() held. | |
275 | * Return -1 if error. | |
276 | */ | |
277 | static abi_ulong mmap_find_vma_aligned(abi_ulong start, abi_ulong size, | |
278 | abi_ulong alignment) | |
279 | { | |
280 | void *ptr, *prev; | |
281 | abi_ulong addr; | |
282 | int flags; | |
283 | int wrapped, repeat; | |
284 | ||
285 | /* If 'start' == 0, then a default start address is used. */ | |
286 | if (start == 0) { | |
287 | start = mmap_next_start; | |
288 | } else { | |
289 | start &= qemu_host_page_mask; | |
84778508 | 290 | } |
84778508 BS |
291 | |
292 | size = HOST_PAGE_ALIGN(size); | |
be04f210 WL |
293 | |
294 | if (reserved_va) { | |
295 | return mmap_find_vma_reserved(start, size, | |
296 | (alignment != 0 ? 1 << alignment : 0)); | |
297 | } | |
298 | ||
84778508 | 299 | addr = start; |
be04f210 WL |
300 | wrapped = repeat = 0; |
301 | prev = 0; | |
953b69cc | 302 | flags = MAP_ANON | MAP_PRIVATE; |
be04f210 WL |
303 | if (alignment != 0) { |
304 | flags |= MAP_ALIGNED(alignment); | |
305 | } | |
be04f210 WL |
306 | |
307 | for (;; prev = ptr) { | |
308 | /* | |
309 | * Reserve needed memory area to avoid a race. | |
310 | * It should be discarded using: | |
311 | * - mmap() with MAP_FIXED flag | |
312 | * - mremap() with MREMAP_FIXED flag | |
313 | * - shmat() with SHM_REMAP flag | |
314 | */ | |
315 | ptr = mmap(g2h_untagged(addr), size, PROT_NONE, | |
316 | flags, -1, 0); | |
317 | ||
318 | /* ENOMEM, if host address space has no memory */ | |
319 | if (ptr == MAP_FAILED) { | |
320 | return (abi_ulong)-1; | |
84778508 | 321 | } |
be04f210 WL |
322 | |
323 | /* | |
324 | * Count the number of sequential returns of the same address. | |
325 | * This is used to modify the search algorithm below. | |
326 | */ | |
327 | repeat = (ptr == prev ? repeat + 1 : 0); | |
328 | ||
329 | if (h2g_valid(ptr + size - 1)) { | |
330 | addr = h2g(ptr); | |
331 | ||
332 | if ((addr & ~TARGET_PAGE_MASK) == 0) { | |
333 | /* Success. */ | |
334 | if (start == mmap_next_start && addr >= TASK_UNMAPPED_BASE) { | |
335 | mmap_next_start = addr + size; | |
336 | } | |
337 | return addr; | |
338 | } | |
339 | ||
340 | /* The address is not properly aligned for the target. */ | |
341 | switch (repeat) { | |
342 | case 0: | |
343 | /* | |
344 | * Assume the result that the kernel gave us is the | |
345 | * first with enough free space, so start again at the | |
346 | * next higher target page. | |
347 | */ | |
348 | addr = TARGET_PAGE_ALIGN(addr); | |
349 | break; | |
350 | case 1: | |
351 | /* | |
352 | * Sometimes the kernel decides to perform the allocation | |
353 | * at the top end of memory instead. | |
354 | */ | |
355 | addr &= TARGET_PAGE_MASK; | |
356 | break; | |
357 | case 2: | |
358 | /* Start over at low memory. */ | |
359 | addr = 0; | |
360 | break; | |
361 | default: | |
362 | /* Fail. This unaligned block must the last. */ | |
363 | addr = -1; | |
364 | break; | |
365 | } | |
366 | } else { | |
367 | /* | |
368 | * Since the result the kernel gave didn't fit, start | |
369 | * again at low memory. If any repetition, fail. | |
370 | */ | |
371 | addr = (repeat ? -1 : 0); | |
372 | } | |
373 | ||
374 | /* Unmap and try again. */ | |
375 | munmap(ptr, size); | |
376 | ||
377 | /* ENOMEM if we checked the whole of the target address space. */ | |
378 | if (addr == (abi_ulong)-1) { | |
379 | return (abi_ulong)-1; | |
380 | } else if (addr == 0) { | |
381 | if (wrapped) { | |
382 | return (abi_ulong)-1; | |
383 | } | |
384 | wrapped = 1; | |
385 | /* | |
386 | * Don't actually use 0 when wrapping, instead indicate | |
387 | * that we'd truly like an allocation in low memory. | |
388 | */ | |
389 | addr = TARGET_PAGE_SIZE; | |
390 | } else if (wrapped && addr >= start) { | |
84778508 | 391 | return (abi_ulong)-1; |
be04f210 | 392 | } |
84778508 | 393 | } |
be04f210 WL |
394 | } |
395 | ||
396 | abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size) | |
397 | { | |
398 | return mmap_find_vma_aligned(start, size, 0); | |
84778508 BS |
399 | } |
400 | ||
401 | /* NOTE: all the constants are the HOST ones */ | |
402 | abi_long target_mmap(abi_ulong start, abi_ulong len, int prot, | |
be04f210 | 403 | int flags, int fd, off_t offset) |
84778508 BS |
404 | { |
405 | abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len; | |
84778508 BS |
406 | |
407 | mmap_lock(); | |
45b8765e WL |
408 | if (qemu_loglevel_mask(CPU_LOG_PAGE)) { |
409 | qemu_log("mmap: start=0x" TARGET_ABI_FMT_lx | |
410 | " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=", | |
411 | start, len, | |
412 | prot & PROT_READ ? 'r' : '-', | |
413 | prot & PROT_WRITE ? 'w' : '-', | |
414 | prot & PROT_EXEC ? 'x' : '-'); | |
6a3b9bfd | 415 | if (flags & MAP_ALIGNMENT_MASK) { |
45b8765e WL |
416 | qemu_log("MAP_ALIGNED(%u) ", |
417 | (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT); | |
6a3b9bfd | 418 | } |
6a3b9bfd | 419 | if (flags & MAP_GUARD) { |
45b8765e | 420 | qemu_log("MAP_GUARD "); |
6a3b9bfd | 421 | } |
6a3b9bfd | 422 | if (flags & MAP_FIXED) { |
45b8765e | 423 | qemu_log("MAP_FIXED "); |
6a3b9bfd | 424 | } |
953b69cc | 425 | if (flags & MAP_ANON) { |
45b8765e | 426 | qemu_log("MAP_ANON "); |
6a3b9bfd | 427 | } |
6a3b9bfd | 428 | if (flags & MAP_EXCL) { |
45b8765e | 429 | qemu_log("MAP_EXCL "); |
6a3b9bfd | 430 | } |
6a3b9bfd | 431 | if (flags & MAP_PRIVATE) { |
45b8765e | 432 | qemu_log("MAP_PRIVATE "); |
6a3b9bfd WL |
433 | } |
434 | if (flags & MAP_SHARED) { | |
45b8765e | 435 | qemu_log("MAP_SHARED "); |
84778508 | 436 | } |
6a3b9bfd | 437 | if (flags & MAP_NOCORE) { |
45b8765e | 438 | qemu_log("MAP_NOCORE "); |
6a3b9bfd | 439 | } |
6a3b9bfd | 440 | if (flags & MAP_STACK) { |
45b8765e | 441 | qemu_log("MAP_STACK "); |
6a3b9bfd | 442 | } |
45b8765e | 443 | qemu_log("fd=%d offset=0x%lx\n", fd, offset); |
84778508 | 444 | } |
84778508 | 445 | |
953b69cc | 446 | if ((flags & MAP_ANON) && fd != -1) { |
be04f210 WL |
447 | errno = EINVAL; |
448 | goto fail; | |
449 | } | |
be04f210 WL |
450 | if (flags & MAP_STACK) { |
451 | if ((fd != -1) || ((prot & (PROT_READ | PROT_WRITE)) != | |
452 | (PROT_READ | PROT_WRITE))) { | |
453 | errno = EINVAL; | |
454 | goto fail; | |
455 | } | |
456 | } | |
be04f210 WL |
457 | if ((flags & MAP_GUARD) && (prot != PROT_NONE || fd != -1 || |
458 | offset != 0 || (flags & (MAP_SHARED | MAP_PRIVATE | | |
459 | /* MAP_PREFAULT | */ /* MAP_PREFAULT not in mman.h */ | |
460 | MAP_PREFAULT_READ | MAP_ANON | MAP_STACK)) != 0)) { | |
461 | errno = EINVAL; | |
462 | goto fail; | |
463 | } | |
be04f210 | 464 | |
84778508 BS |
465 | if (offset & ~TARGET_PAGE_MASK) { |
466 | errno = EINVAL; | |
467 | goto fail; | |
468 | } | |
469 | ||
be04f210 WL |
470 | if (len == 0) { |
471 | errno = EINVAL; | |
472 | goto fail; | |
473 | } | |
14837a3f WL |
474 | |
475 | /* Check for overflows */ | |
476 | len = TARGET_PAGE_ALIGN(len); | |
477 | if (len == 0) { | |
478 | errno = ENOMEM; | |
479 | goto fail; | |
480 | } | |
481 | ||
84778508 | 482 | real_start = start & qemu_host_page_mask; |
be04f210 | 483 | host_offset = offset & qemu_host_page_mask; |
84778508 | 484 | |
be04f210 WL |
485 | /* |
486 | * If the user is asking for the kernel to find a location, do that | |
487 | * before we truncate the length for mapping files below. | |
488 | */ | |
84778508 | 489 | if (!(flags & MAP_FIXED)) { |
84778508 BS |
490 | host_len = len + offset - host_offset; |
491 | host_len = HOST_PAGE_ALIGN(host_len); | |
be04f210 WL |
492 | if ((flags & MAP_ALIGNMENT_MASK) != 0) |
493 | start = mmap_find_vma_aligned(real_start, host_len, | |
494 | (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT); | |
495 | else | |
496 | start = mmap_find_vma(real_start, host_len); | |
497 | if (start == (abi_ulong)-1) { | |
84778508 BS |
498 | errno = ENOMEM; |
499 | goto fail; | |
500 | } | |
be04f210 WL |
501 | } |
502 | ||
503 | /* | |
504 | * When mapping files into a memory area larger than the file, accesses | |
505 | * to pages beyond the file size will cause a SIGBUS. | |
506 | * | |
507 | * For example, if mmaping a file of 100 bytes on a host with 4K pages | |
508 | * emulating a target with 8K pages, the target expects to be able to | |
509 | * access the first 8K. But the host will trap us on any access beyond | |
510 | * 4K. | |
511 | * | |
512 | * When emulating a target with a larger page-size than the hosts, we | |
513 | * may need to truncate file maps at EOF and add extra anonymous pages | |
514 | * up to the targets page boundary. | |
515 | */ | |
516 | ||
8e3b0cbb | 517 | if ((qemu_real_host_page_size() < qemu_host_page_size) && fd != -1) { |
be04f210 WL |
518 | struct stat sb; |
519 | ||
520 | if (fstat(fd, &sb) == -1) { | |
521 | goto fail; | |
522 | } | |
523 | ||
524 | /* Are we trying to create a map beyond EOF?. */ | |
525 | if (offset + len > sb.st_size) { | |
526 | /* | |
527 | * If so, truncate the file map at eof aligned with | |
528 | * the hosts real pagesize. Additional anonymous maps | |
529 | * will be created beyond EOF. | |
530 | */ | |
531 | len = REAL_HOST_PAGE_ALIGN(sb.st_size - offset); | |
532 | } | |
533 | } | |
534 | ||
535 | if (!(flags & MAP_FIXED)) { | |
536 | unsigned long host_start; | |
537 | void *p; | |
538 | ||
539 | host_len = len + offset - host_offset; | |
540 | host_len = HOST_PAGE_ALIGN(host_len); | |
541 | ||
542 | /* | |
543 | * Note: we prefer to control the mapping address. It is | |
544 | * especially important if qemu_host_page_size > | |
545 | * qemu_real_host_page_size | |
546 | */ | |
547 | p = mmap(g2h_untagged(start), host_len, prot, | |
953b69cc | 548 | flags | MAP_FIXED | ((fd != -1) ? MAP_ANON : 0), -1, 0); |
84778508 BS |
549 | if (p == MAP_FAILED) |
550 | goto fail; | |
551 | /* update start so that it points to the file position at 'offset' */ | |
552 | host_start = (unsigned long)p; | |
be04f210 WL |
553 | if (fd != -1) { |
554 | p = mmap(g2h_untagged(start), len, prot, | |
555 | flags | MAP_FIXED, fd, host_offset); | |
556 | if (p == MAP_FAILED) { | |
557 | munmap(g2h_untagged(start), host_len); | |
558 | goto fail; | |
559 | } | |
84778508 | 560 | host_start += offset - host_offset; |
be04f210 | 561 | } |
84778508 BS |
562 | start = h2g(host_start); |
563 | } else { | |
84778508 BS |
564 | if (start & ~TARGET_PAGE_MASK) { |
565 | errno = EINVAL; | |
566 | goto fail; | |
567 | } | |
568 | end = start + len; | |
569 | real_end = HOST_PAGE_ALIGN(end); | |
570 | ||
be04f210 WL |
571 | /* |
572 | * Test if requested memory area fits target address space | |
573 | * It can fail only on 64-bit host with 32-bit target. | |
574 | * On any other target/host host mmap() handles this error correctly. | |
575 | */ | |
0fc76b68 | 576 | if (!guest_range_valid_untagged(start, len)) { |
be04f210 WL |
577 | errno = EINVAL; |
578 | goto fail; | |
84778508 BS |
579 | } |
580 | ||
be04f210 WL |
581 | /* |
582 | * worst case: we cannot map the file because the offset is not | |
583 | * aligned, so we read it | |
584 | */ | |
a6b2d060 | 585 | if (fd != -1 && |
84778508 | 586 | (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { |
be04f210 WL |
587 | /* |
588 | * msync() won't work here, so we return an error if write is | |
589 | * possible while it is a shared mapping | |
590 | */ | |
6c173b3c | 591 | if ((flags & TARGET_BSD_MAP_FLAGMASK) == MAP_SHARED && |
84778508 BS |
592 | (prot & PROT_WRITE)) { |
593 | errno = EINVAL; | |
594 | goto fail; | |
595 | } | |
596 | retaddr = target_mmap(start, len, prot | PROT_WRITE, | |
597 | MAP_FIXED | MAP_PRIVATE | MAP_ANON, | |
598 | -1, 0); | |
599 | if (retaddr == -1) | |
600 | goto fail; | |
26778ac3 MU |
601 | if (pread(fd, g2h_untagged(start), len, offset) == -1) { |
602 | goto fail; | |
603 | } | |
84778508 BS |
604 | if (!(prot & PROT_WRITE)) { |
605 | ret = target_mprotect(start, len, prot); | |
91a5adda | 606 | assert(ret == 0); |
84778508 BS |
607 | } |
608 | goto the_end; | |
609 | } | |
610 | ||
0fc76b68 KE |
611 | /* Reject the mapping if any page within the range is mapped */ |
612 | if ((flags & MAP_EXCL) && page_check_range(start, len, 0) < 0) { | |
613 | errno = EINVAL; | |
614 | goto fail; | |
615 | } | |
616 | ||
84778508 BS |
617 | /* handle the start of the mapping */ |
618 | if (start > real_start) { | |
619 | if (real_end == real_start + qemu_host_page_size) { | |
620 | /* one single host page */ | |
621 | ret = mmap_frag(real_start, start, end, | |
622 | prot, flags, fd, offset); | |
623 | if (ret == -1) | |
624 | goto fail; | |
625 | goto the_end1; | |
626 | } | |
627 | ret = mmap_frag(real_start, start, real_start + qemu_host_page_size, | |
628 | prot, flags, fd, offset); | |
629 | if (ret == -1) | |
630 | goto fail; | |
631 | real_start += qemu_host_page_size; | |
632 | } | |
633 | /* handle the end of the mapping */ | |
634 | if (end < real_end) { | |
635 | ret = mmap_frag(real_end - qemu_host_page_size, | |
be04f210 | 636 | real_end - qemu_host_page_size, end, |
84778508 BS |
637 | prot, flags, fd, |
638 | offset + real_end - qemu_host_page_size - start); | |
639 | if (ret == -1) | |
640 | goto fail; | |
641 | real_end -= qemu_host_page_size; | |
642 | } | |
643 | ||
644 | /* map the middle (easier) */ | |
645 | if (real_start < real_end) { | |
646 | void *p; | |
647 | unsigned long offset1; | |
648 | if (flags & MAP_ANON) | |
649 | offset1 = 0; | |
650 | else | |
651 | offset1 = offset + real_start - start; | |
3e8f1628 | 652 | p = mmap(g2h_untagged(real_start), real_end - real_start, |
84778508 BS |
653 | prot, flags, fd, offset1); |
654 | if (p == MAP_FAILED) | |
655 | goto fail; | |
656 | } | |
657 | } | |
658 | the_end1: | |
659 | page_set_flags(start, start + len, prot | PAGE_VALID); | |
660 | the_end: | |
661 | #ifdef DEBUG_MMAP | |
6a3b9bfd | 662 | printf("ret=0x" TARGET_ABI_FMT_lx "\n", start); |
84778508 BS |
663 | page_dump(stdout); |
664 | printf("\n"); | |
665 | #endif | |
666 | mmap_unlock(); | |
667 | return start; | |
668 | fail: | |
669 | mmap_unlock(); | |
670 | return -1; | |
671 | } | |
672 | ||
be04f210 WL |
673 | static void mmap_reserve(abi_ulong start, abi_ulong size) |
674 | { | |
675 | abi_ulong real_start; | |
676 | abi_ulong real_end; | |
677 | abi_ulong addr; | |
678 | abi_ulong end; | |
679 | int prot; | |
680 | ||
681 | real_start = start & qemu_host_page_mask; | |
682 | real_end = HOST_PAGE_ALIGN(start + size); | |
683 | end = start + size; | |
684 | if (start > real_start) { | |
685 | /* handle host page containing start */ | |
686 | prot = 0; | |
687 | for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) { | |
688 | prot |= page_get_flags(addr); | |
689 | } | |
690 | if (real_end == real_start + qemu_host_page_size) { | |
691 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { | |
692 | prot |= page_get_flags(addr); | |
693 | } | |
694 | end = real_end; | |
695 | } | |
696 | if (prot != 0) { | |
697 | real_start += qemu_host_page_size; | |
698 | } | |
699 | } | |
700 | if (end < real_end) { | |
701 | prot = 0; | |
702 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { | |
703 | prot |= page_get_flags(addr); | |
704 | } | |
705 | if (prot != 0) { | |
706 | real_end -= qemu_host_page_size; | |
707 | } | |
708 | } | |
709 | if (real_start != real_end) { | |
710 | mmap(g2h_untagged(real_start), real_end - real_start, PROT_NONE, | |
953b69cc | 711 | MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0); |
be04f210 WL |
712 | } |
713 | } | |
714 | ||
84778508 BS |
715 | int target_munmap(abi_ulong start, abi_ulong len) |
716 | { | |
717 | abi_ulong end, real_start, real_end, addr; | |
718 | int prot, ret; | |
719 | ||
720 | #ifdef DEBUG_MMAP | |
6a3b9bfd WL |
721 | printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x" |
722 | TARGET_ABI_FMT_lx "\n", | |
723 | start, len); | |
84778508 BS |
724 | #endif |
725 | if (start & ~TARGET_PAGE_MASK) | |
726 | return -EINVAL; | |
727 | len = TARGET_PAGE_ALIGN(len); | |
728 | if (len == 0) | |
729 | return -EINVAL; | |
730 | mmap_lock(); | |
731 | end = start + len; | |
732 | real_start = start & qemu_host_page_mask; | |
733 | real_end = HOST_PAGE_ALIGN(end); | |
734 | ||
735 | if (start > real_start) { | |
736 | /* handle host page containing start */ | |
737 | prot = 0; | |
5be1d0b5 | 738 | for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
739 | prot |= page_get_flags(addr); |
740 | } | |
741 | if (real_end == real_start + qemu_host_page_size) { | |
5be1d0b5 | 742 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
743 | prot |= page_get_flags(addr); |
744 | } | |
745 | end = real_end; | |
746 | } | |
747 | if (prot != 0) | |
748 | real_start += qemu_host_page_size; | |
749 | } | |
750 | if (end < real_end) { | |
751 | prot = 0; | |
5be1d0b5 | 752 | for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) { |
84778508 BS |
753 | prot |= page_get_flags(addr); |
754 | } | |
755 | if (prot != 0) | |
756 | real_end -= qemu_host_page_size; | |
757 | } | |
758 | ||
759 | ret = 0; | |
760 | /* unmap what we can */ | |
761 | if (real_start < real_end) { | |
be04f210 WL |
762 | if (reserved_va) { |
763 | mmap_reserve(real_start, real_end - real_start); | |
764 | } else { | |
765 | ret = munmap(g2h_untagged(real_start), real_end - real_start); | |
766 | } | |
84778508 BS |
767 | } |
768 | ||
be04f210 | 769 | if (ret == 0) { |
84778508 | 770 | page_set_flags(start, start + len, 0); |
be04f210 | 771 | } |
84778508 BS |
772 | mmap_unlock(); |
773 | return ret; | |
774 | } | |
775 | ||
776 | int target_msync(abi_ulong start, abi_ulong len, int flags) | |
777 | { | |
778 | abi_ulong end; | |
779 | ||
780 | if (start & ~TARGET_PAGE_MASK) | |
781 | return -EINVAL; | |
782 | len = TARGET_PAGE_ALIGN(len); | |
783 | end = start + len; | |
784 | if (end < start) | |
785 | return -EINVAL; | |
786 | if (end == start) | |
787 | return 0; | |
788 | ||
789 | start &= qemu_host_page_mask; | |
3e8f1628 | 790 | return msync(g2h_untagged(start), end - start, flags); |
84778508 | 791 | } |