| 1 |
/* |
| 2 |
* vm_alloc.cpp - Wrapper to various virtual memory allocation schemes |
| 3 |
* (supports mmap, vm_allocate or fallbacks to malloc) |
| 4 |
* |
| 5 |
* Basilisk II (C) 1997-2008 Christian Bauer |
| 6 |
* |
| 7 |
* This program is free software; you can redistribute it and/or modify |
| 8 |
* it under the terms of the GNU General Public License as published by |
| 9 |
* the Free Software Foundation; either version 2 of the License, or |
| 10 |
* (at your option) any later version. |
| 11 |
* |
| 12 |
* This program is distributed in the hope that it will be useful, |
| 13 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 |
* GNU General Public License for more details. |
| 16 |
* |
| 17 |
* You should have received a copy of the GNU General Public License |
| 18 |
* along with this program; if not, write to the Free Software |
| 19 |
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 20 |
*/ |
| 21 |
|
| 22 |
#ifdef HAVE_CONFIG_H |
| 23 |
#include "config.h" |
| 24 |
#endif |
| 25 |
|
| 26 |
#ifdef HAVE_FCNTL_H |
| 27 |
#include <fcntl.h> |
| 28 |
#endif |
| 29 |
|
| 30 |
#ifdef HAVE_WIN32_VM |
| 31 |
#define WIN32_LEAN_AND_MEAN /* avoid including junk */ |
| 32 |
#include <windows.h> |
| 33 |
#endif |
| 34 |
|
| 35 |
#include <errno.h> |
| 36 |
#include <stdio.h> |
| 37 |
#include <stdlib.h> |
| 38 |
#include <string.h> |
| 39 |
#include <limits.h> |
| 40 |
#include "vm_alloc.h" |
| 41 |
|
| 42 |
#if defined(__APPLE__) && defined(__MACH__) |
| 43 |
#include <sys/utsname.h> |
| 44 |
#endif |
| 45 |
|
| 46 |
#ifdef HAVE_MACH_VM |
| 47 |
#ifndef HAVE_MACH_TASK_SELF |
| 48 |
#ifdef HAVE_TASK_SELF |
| 49 |
#define mach_task_self task_self |
| 50 |
#else |
| 51 |
#error "No task_self(), you lose." |
| 52 |
#endif |
| 53 |
#endif |
| 54 |
#endif |
| 55 |
|
| 56 |
#ifdef HAVE_WIN32_VM |
| 57 |
/* Windows is either ILP32 or LLP64 */ |
| 58 |
typedef UINT_PTR vm_uintptr_t; |
| 59 |
#else |
| 60 |
/* Other systems are sane as they are either ILP32 or LP64 */ |
| 61 |
typedef unsigned long vm_uintptr_t; |
| 62 |
#endif |
| 63 |
|
| 64 |
/* We want MAP_32BIT, if available, for SheepShaver and BasiliskII |
| 65 |
because the emulated target is 32-bit and this helps to allocate |
| 66 |
memory so that branches could be resolved more easily (32-bit |
| 67 |
displacement to code in .text), on AMD64 for example. */ |
| 68 |
#if defined(__hpux) |
| 69 |
#define MAP_32BIT MAP_ADDR32 |
| 70 |
#endif |
| 71 |
#ifndef MAP_32BIT |
| 72 |
#define MAP_32BIT 0 |
| 73 |
#endif |
| 74 |
#ifndef MAP_ANON |
| 75 |
#define MAP_ANON 0 |
| 76 |
#endif |
| 77 |
#ifndef MAP_ANONYMOUS |
| 78 |
#define MAP_ANONYMOUS 0 |
| 79 |
#endif |
| 80 |
|
| 81 |
#define MAP_EXTRA_FLAGS (MAP_32BIT) |
| 82 |
|
| 83 |
#ifdef HAVE_MMAP_VM |
| 84 |
#if (defined(__linux__) && defined(__i386__)) || HAVE_LINKER_SCRIPT |
| 85 |
/* Force a reasonnable address below 0x80000000 on x86 so that we |
| 86 |
don't get addresses above when the program is run on AMD64. |
| 87 |
NOTE: this is empirically determined on Linux/x86. */ |
| 88 |
#define MAP_BASE 0x10000000 |
| 89 |
#else |
| 90 |
#define MAP_BASE 0x00000000 |
| 91 |
#endif |
| 92 |
static char * next_address = (char *)MAP_BASE; |
| 93 |
#ifdef HAVE_MMAP_ANON |
| 94 |
#define map_flags (MAP_ANON | MAP_EXTRA_FLAGS) |
| 95 |
#define zero_fd -1 |
| 96 |
#else |
| 97 |
#ifdef HAVE_MMAP_ANONYMOUS |
| 98 |
#define map_flags (MAP_ANONYMOUS | MAP_EXTRA_FLAGS) |
| 99 |
#define zero_fd -1 |
| 100 |
#else |
| 101 |
#define map_flags (MAP_EXTRA_FLAGS) |
| 102 |
static int zero_fd = -1; |
| 103 |
#endif |
| 104 |
#endif |
| 105 |
#endif |
| 106 |
|
| 107 |
/* Translate generic VM map flags to host values. */ |
| 108 |
|
| 109 |
#ifdef HAVE_MMAP_VM |
| 110 |
static int translate_map_flags(int vm_flags) |
| 111 |
{ |
| 112 |
int flags = 0; |
| 113 |
if (vm_flags & VM_MAP_SHARED) |
| 114 |
flags |= MAP_SHARED; |
| 115 |
if (vm_flags & VM_MAP_PRIVATE) |
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flags |= MAP_PRIVATE; |
| 117 |
if (vm_flags & VM_MAP_FIXED) |
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flags |= MAP_FIXED; |
| 119 |
if (vm_flags & VM_MAP_32BIT) |
| 120 |
flags |= MAP_32BIT; |
| 121 |
return flags; |
| 122 |
} |
| 123 |
#endif |
| 124 |
|
| 125 |
/* Align ADDR and SIZE to 64K boundaries. */ |
| 126 |
|
| 127 |
#ifdef HAVE_WIN32_VM |
| 128 |
static inline LPVOID align_addr_segment(LPVOID addr) |
| 129 |
{ |
| 130 |
return (LPVOID)(((vm_uintptr_t)addr) & -((vm_uintptr_t)65536)); |
| 131 |
} |
| 132 |
|
| 133 |
static inline DWORD align_size_segment(LPVOID addr, DWORD size) |
| 134 |
{ |
| 135 |
return size + ((vm_uintptr_t)addr - (vm_uintptr_t)align_addr_segment(addr)); |
| 136 |
} |
| 137 |
#endif |
| 138 |
|
| 139 |
/* Translate generic VM prot flags to host values. */ |
| 140 |
|
| 141 |
#ifdef HAVE_WIN32_VM |
| 142 |
static int translate_prot_flags(int prot_flags) |
| 143 |
{ |
| 144 |
int prot = PAGE_READWRITE; |
| 145 |
if (prot_flags == (VM_PAGE_EXECUTE | VM_PAGE_READ | VM_PAGE_WRITE)) |
| 146 |
prot = PAGE_EXECUTE_READWRITE; |
| 147 |
else if (prot_flags == (VM_PAGE_EXECUTE | VM_PAGE_READ)) |
| 148 |
prot = PAGE_EXECUTE_READ; |
| 149 |
else if (prot_flags == (VM_PAGE_READ | VM_PAGE_WRITE)) |
| 150 |
prot = PAGE_READWRITE; |
| 151 |
else if (prot_flags == VM_PAGE_READ) |
| 152 |
prot = PAGE_READONLY; |
| 153 |
else if (prot_flags == 0) |
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prot = PAGE_NOACCESS; |
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return prot; |
| 156 |
} |
| 157 |
#endif |
| 158 |
|
| 159 |
/* Translate Mach return codes to POSIX errno values. */ |
| 160 |
#ifdef HAVE_MACH_VM |
| 161 |
static int vm_error(kern_return_t ret_code) |
| 162 |
{ |
| 163 |
switch (ret_code) { |
| 164 |
case KERN_SUCCESS: |
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return 0; |
| 166 |
case KERN_INVALID_ADDRESS: |
| 167 |
case KERN_NO_SPACE: |
| 168 |
return ENOMEM; |
| 169 |
case KERN_PROTECTION_FAILURE: |
| 170 |
return EACCES; |
| 171 |
default: |
| 172 |
return EINVAL; |
| 173 |
} |
| 174 |
} |
| 175 |
#endif |
| 176 |
|
| 177 |
/* Initialize the VM system. Returns 0 if successful, -1 for errors. */ |
| 178 |
|
| 179 |
int vm_init(void) |
| 180 |
{ |
| 181 |
#ifdef HAVE_MMAP_VM |
| 182 |
#ifndef zero_fd |
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zero_fd = open("/dev/zero", O_RDWR); |
| 184 |
if (zero_fd < 0) |
| 185 |
return -1; |
| 186 |
#endif |
| 187 |
#endif |
| 188 |
|
| 189 |
// On 10.4 and earlier, reset CrashReporter's task signal handler to |
| 190 |
// avoid having it show up for signals that get handled. |
| 191 |
#if defined(__APPLE__) && defined(__MACH__) |
| 192 |
struct utsname info; |
| 193 |
|
| 194 |
if (!uname(&info) && atoi(info.release) <= 8) { |
| 195 |
task_set_exception_ports(mach_task_self(), |
| 196 |
EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC, |
| 197 |
MACH_PORT_NULL, |
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EXCEPTION_STATE_IDENTITY, |
| 199 |
MACHINE_THREAD_STATE); |
| 200 |
} |
| 201 |
#endif |
| 202 |
|
| 203 |
return 0; |
| 204 |
} |
| 205 |
|
| 206 |
/* Deallocate all internal data used to wrap virtual memory allocators. */ |
| 207 |
|
| 208 |
void vm_exit(void) |
| 209 |
{ |
| 210 |
#ifdef HAVE_MMAP_VM |
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#ifndef zero_fd |
| 212 |
if (zero_fd != -1) { |
| 213 |
close(zero_fd); |
| 214 |
zero_fd = -1; |
| 215 |
} |
| 216 |
#endif |
| 217 |
#endif |
| 218 |
} |
| 219 |
|
| 220 |
/* Allocate zero-filled memory of SIZE bytes. The mapping is private |
| 221 |
and default protection bits are read / write. The return value |
| 222 |
is the actual mapping address chosen or VM_MAP_FAILED for errors. */ |
| 223 |
|
| 224 |
void * vm_acquire(size_t size, int options) |
| 225 |
{ |
| 226 |
void * addr; |
| 227 |
|
| 228 |
errno = 0; |
| 229 |
|
| 230 |
// VM_MAP_FIXED are to be used with vm_acquire_fixed() only |
| 231 |
if (options & VM_MAP_FIXED) |
| 232 |
return VM_MAP_FAILED; |
| 233 |
|
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#ifndef HAVE_VM_WRITE_WATCH |
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if (options & VM_MAP_WRITE_WATCH) |
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return VM_MAP_FAILED; |
| 237 |
#endif |
| 238 |
|
| 239 |
#if defined(HAVE_MACH_VM) |
| 240 |
// vm_allocate() returns a zero-filled memory region |
| 241 |
kern_return_t ret_code = vm_allocate(mach_task_self(), (vm_address_t *)&addr, size, TRUE); |
| 242 |
if (ret_code != KERN_SUCCESS) { |
| 243 |
errno = vm_error(ret_code); |
| 244 |
return VM_MAP_FAILED; |
| 245 |
} |
| 246 |
#elif defined(HAVE_MMAP_VM) |
| 247 |
int fd = zero_fd; |
| 248 |
int the_map_flags = translate_map_flags(options) | map_flags; |
| 249 |
|
| 250 |
if ((addr = mmap((caddr_t)next_address, size, VM_PAGE_DEFAULT, the_map_flags, fd, 0)) == (void *)MAP_FAILED) |
| 251 |
return VM_MAP_FAILED; |
| 252 |
|
| 253 |
// Sanity checks for 64-bit platforms |
| 254 |
if (sizeof(void *) == 8 && (options & VM_MAP_32BIT) && !((char *)addr <= (char *)0xffffffff)) |
| 255 |
return VM_MAP_FAILED; |
| 256 |
|
| 257 |
next_address = (char *)addr + size; |
| 258 |
#elif defined(HAVE_WIN32_VM) |
| 259 |
int alloc_type = MEM_RESERVE | MEM_COMMIT; |
| 260 |
if (options & VM_MAP_WRITE_WATCH) |
| 261 |
alloc_type |= MEM_WRITE_WATCH; |
| 262 |
|
| 263 |
if ((addr = VirtualAlloc(NULL, size, alloc_type, PAGE_EXECUTE_READWRITE)) == NULL) |
| 264 |
return VM_MAP_FAILED; |
| 265 |
#else |
| 266 |
if ((addr = calloc(size, 1)) == 0) |
| 267 |
return VM_MAP_FAILED; |
| 268 |
|
| 269 |
// Omit changes for protections because they are not supported in this mode |
| 270 |
return addr; |
| 271 |
#endif |
| 272 |
|
| 273 |
// Explicitely protect the newly mapped region here because on some systems, |
| 274 |
// say MacOS X, mmap() doesn't honour the requested protection flags. |
| 275 |
if (vm_protect(addr, size, VM_PAGE_DEFAULT) != 0) |
| 276 |
return VM_MAP_FAILED; |
| 277 |
|
| 278 |
return addr; |
| 279 |
} |
| 280 |
|
| 281 |
/* Allocate zero-filled memory at exactly ADDR (which must be page-aligned). |
| 282 |
Retuns 0 if successful, -1 on errors. */ |
| 283 |
|
| 284 |
int vm_acquire_fixed(void * addr, size_t size, int options) |
| 285 |
{ |
| 286 |
errno = 0; |
| 287 |
|
| 288 |
// Fixed mappings are required to be private |
| 289 |
if (options & VM_MAP_SHARED) |
| 290 |
return -1; |
| 291 |
|
| 292 |
#ifndef HAVE_VM_WRITE_WATCH |
| 293 |
if (options & VM_MAP_WRITE_WATCH) |
| 294 |
return -1; |
| 295 |
#endif |
| 296 |
|
| 297 |
#if defined(HAVE_MACH_VM) |
| 298 |
// vm_allocate() returns a zero-filled memory region |
| 299 |
kern_return_t ret_code = vm_allocate(mach_task_self(), (vm_address_t *)&addr, size, 0); |
| 300 |
if (ret_code != KERN_SUCCESS) { |
| 301 |
errno = vm_error(ret_code); |
| 302 |
return -1; |
| 303 |
} |
| 304 |
#elif defined(HAVE_MMAP_VM) |
| 305 |
int fd = zero_fd; |
| 306 |
int the_map_flags = translate_map_flags(options) | map_flags | MAP_FIXED; |
| 307 |
|
| 308 |
if (mmap((caddr_t)addr, size, VM_PAGE_DEFAULT, the_map_flags, fd, 0) == (void *)MAP_FAILED) |
| 309 |
return -1; |
| 310 |
#elif defined(HAVE_WIN32_VM) |
| 311 |
// Windows cannot allocate Low Memory |
| 312 |
if (addr == NULL) |
| 313 |
return -1; |
| 314 |
|
| 315 |
int alloc_type = MEM_RESERVE | MEM_COMMIT; |
| 316 |
if (options & VM_MAP_WRITE_WATCH) |
| 317 |
alloc_type |= MEM_WRITE_WATCH; |
| 318 |
|
| 319 |
// Allocate a possibly offset region to align on 64K boundaries |
| 320 |
LPVOID req_addr = align_addr_segment(addr); |
| 321 |
DWORD req_size = align_size_segment(addr, size); |
| 322 |
LPVOID ret_addr = VirtualAlloc(req_addr, req_size, alloc_type, PAGE_EXECUTE_READWRITE); |
| 323 |
if (ret_addr != req_addr) |
| 324 |
return -1; |
| 325 |
#else |
| 326 |
// Unsupported |
| 327 |
return -1; |
| 328 |
#endif |
| 329 |
|
| 330 |
// Explicitely protect the newly mapped region here because on some systems, |
| 331 |
// say MacOS X, mmap() doesn't honour the requested protection flags. |
| 332 |
if (vm_protect(addr, size, VM_PAGE_DEFAULT) != 0) |
| 333 |
return -1; |
| 334 |
|
| 335 |
return 0; |
| 336 |
} |
| 337 |
|
| 338 |
/* Deallocate any mapping for the region starting at ADDR and extending |
| 339 |
LEN bytes. Returns 0 if successful, -1 on errors. */ |
| 340 |
|
| 341 |
int vm_release(void * addr, size_t size) |
| 342 |
{ |
| 343 |
// Safety check: don't try to release memory that was not allocated |
| 344 |
if (addr == VM_MAP_FAILED) |
| 345 |
return 0; |
| 346 |
|
| 347 |
#ifdef HAVE_MACH_VM |
| 348 |
if (vm_deallocate(mach_task_self(), (vm_address_t)addr, size) != KERN_SUCCESS) |
| 349 |
return -1; |
| 350 |
#else |
| 351 |
#ifdef HAVE_MMAP_VM |
| 352 |
if (munmap((caddr_t)addr, size) != 0) |
| 353 |
return -1; |
| 354 |
#else |
| 355 |
#ifdef HAVE_WIN32_VM |
| 356 |
if (VirtualFree(align_addr_segment(addr), 0, MEM_RELEASE) == 0) |
| 357 |
return -1; |
| 358 |
#else |
| 359 |
free(addr); |
| 360 |
#endif |
| 361 |
#endif |
| 362 |
#endif |
| 363 |
|
| 364 |
return 0; |
| 365 |
} |
| 366 |
|
| 367 |
/* Change the memory protection of the region starting at ADDR and |
| 368 |
extending LEN bytes to PROT. Returns 0 if successful, -1 for errors. */ |
| 369 |
|
| 370 |
int vm_protect(void * addr, size_t size, int prot) |
| 371 |
{ |
| 372 |
#ifdef HAVE_MACH_VM |
| 373 |
int ret_code = vm_protect(mach_task_self(), (vm_address_t)addr, size, 0, prot); |
| 374 |
return ret_code == KERN_SUCCESS ? 0 : -1; |
| 375 |
#else |
| 376 |
#ifdef HAVE_MMAP_VM |
| 377 |
int ret_code = mprotect((caddr_t)addr, size, prot); |
| 378 |
return ret_code == 0 ? 0 : -1; |
| 379 |
#else |
| 380 |
#ifdef HAVE_WIN32_VM |
| 381 |
DWORD old_prot; |
| 382 |
int ret_code = VirtualProtect(addr, size, translate_prot_flags(prot), &old_prot); |
| 383 |
return ret_code != 0 ? 0 : -1; |
| 384 |
#else |
| 385 |
// Unsupported |
| 386 |
return -1; |
| 387 |
#endif |
| 388 |
#endif |
| 389 |
#endif |
| 390 |
} |
| 391 |
|
| 392 |
/* Return the addresses of the pages that got modified in the |
| 393 |
specified range [ ADDR, ADDR + SIZE [ since the last reset of the watch |
| 394 |
bits. Returns 0 if successful, -1 for errors. */ |
| 395 |
|
| 396 |
int vm_get_write_watch(void * addr, size_t size, |
| 397 |
void ** pages, unsigned int * n_pages, |
| 398 |
int options) |
| 399 |
{ |
| 400 |
#ifdef HAVE_VM_WRITE_WATCH |
| 401 |
#ifdef HAVE_WIN32_VM |
| 402 |
DWORD flags = 0; |
| 403 |
if (options & VM_WRITE_WATCH_RESET) |
| 404 |
flags |= WRITE_WATCH_FLAG_RESET; |
| 405 |
|
| 406 |
ULONG page_size; |
| 407 |
ULONG_PTR count = *n_pages; |
| 408 |
int ret_code = GetWriteWatch(flags, addr, size, pages, &count, &page_size); |
| 409 |
if (ret_code != 0) |
| 410 |
return -1; |
| 411 |
|
| 412 |
*n_pages = count; |
| 413 |
return 0; |
| 414 |
#endif |
| 415 |
#endif |
| 416 |
// Unsupported |
| 417 |
return -1; |
| 418 |
} |
| 419 |
|
| 420 |
/* Reset the write-tracking state for the specified range [ ADDR, ADDR |
| 421 |
+ SIZE [. Returns 0 if successful, -1 for errors. */ |
| 422 |
|
| 423 |
int vm_reset_write_watch(void * addr, size_t size) |
| 424 |
{ |
| 425 |
#ifdef HAVE_VM_WRITE_WATCH |
| 426 |
#ifdef HAVE_WIN32_VM |
| 427 |
int ret_code = ResetWriteWatch(addr, size); |
| 428 |
return ret_code == 0 ? 0 : -1; |
| 429 |
#endif |
| 430 |
#endif |
| 431 |
// Unsupported |
| 432 |
return -1; |
| 433 |
} |
| 434 |
|
| 435 |
/* Returns the size of a page. */ |
| 436 |
|
| 437 |
int vm_get_page_size(void) |
| 438 |
{ |
| 439 |
#ifdef HAVE_WIN32_VM |
| 440 |
static vm_uintptr_t page_size = 0; |
| 441 |
if (page_size == 0) { |
| 442 |
SYSTEM_INFO si; |
| 443 |
GetSystemInfo(&si); |
| 444 |
page_size = si.dwAllocationGranularity; |
| 445 |
} |
| 446 |
return page_size; |
| 447 |
#else |
| 448 |
return getpagesize(); |
| 449 |
#endif |
| 450 |
} |
| 451 |
|
| 452 |
#ifdef CONFIGURE_TEST_VM_WRITE_WATCH |
| 453 |
int main(void) |
| 454 |
{ |
| 455 |
int i, j; |
| 456 |
|
| 457 |
vm_init(); |
| 458 |
|
| 459 |
vm_uintptr_t page_size = vm_get_page_size(); |
| 460 |
|
| 461 |
char *area; |
| 462 |
const int n_pages = 7; |
| 463 |
const int area_size = n_pages * page_size; |
| 464 |
const int map_options = VM_MAP_DEFAULT | VM_MAP_WRITE_WATCH; |
| 465 |
if ((area = (char *)vm_acquire(area_size, map_options)) == VM_MAP_FAILED) |
| 466 |
return 1; |
| 467 |
|
| 468 |
unsigned int n_modified_pages_expected = 0; |
| 469 |
static const int touch_page[n_pages] = { 0, 1, 1, 0, 1, 0, 1 }; |
| 470 |
for (i = 0; i < n_pages; i++) { |
| 471 |
if (touch_page[i]) { |
| 472 |
area[i * page_size] = 1; |
| 473 |
++n_modified_pages_expected; |
| 474 |
} |
| 475 |
} |
| 476 |
|
| 477 |
char *modified_pages[n_pages]; |
| 478 |
unsigned int n_modified_pages = n_pages; |
| 479 |
if (vm_get_write_watch(area, area_size, (void **)modified_pages, &n_modified_pages) < 0) |
| 480 |
return 2; |
| 481 |
if (n_modified_pages != n_modified_pages_expected) |
| 482 |
return 3; |
| 483 |
for (i = 0, j = 0; i < n_pages; i++) { |
| 484 |
char v = area[i * page_size]; |
| 485 |
if ((touch_page[i] && !v) || (!touch_page[i] && v)) |
| 486 |
return 4; |
| 487 |
if (!touch_page[i]) |
| 488 |
continue; |
| 489 |
if (modified_pages[j] != (area + i * page_size)) |
| 490 |
return 5; |
| 491 |
++j; |
| 492 |
} |
| 493 |
|
| 494 |
vm_release(area, area_size); |
| 495 |
return 0; |
| 496 |
} |
| 497 |
#endif |
| 498 |
|
| 499 |
#ifdef CONFIGURE_TEST_VM_MAP |
| 500 |
#include <stdlib.h> |
| 501 |
#include <signal.h> |
| 502 |
|
| 503 |
static void fault_handler(int sig) |
| 504 |
{ |
| 505 |
exit(1); |
| 506 |
} |
| 507 |
|
| 508 |
/* Tests covered here: |
| 509 |
- TEST_VM_PROT_* program slices actually succeeds when a crash occurs |
| 510 |
- TEST_VM_MAP_ANON* program slices succeeds when it could be compiled |
| 511 |
*/ |
| 512 |
int main(void) |
| 513 |
{ |
| 514 |
vm_init(); |
| 515 |
|
| 516 |
signal(SIGSEGV, fault_handler); |
| 517 |
#ifdef SIGBUS |
| 518 |
signal(SIGBUS, fault_handler); |
| 519 |
#endif |
| 520 |
|
| 521 |
#define page_align(address) ((char *)((vm_uintptr_t)(address) & -page_size)) |
| 522 |
vm_uintptr_t page_size = vm_get_page_size(); |
| 523 |
|
| 524 |
const int area_size = 6 * page_size; |
| 525 |
volatile char * area = (volatile char *) vm_acquire(area_size); |
| 526 |
volatile char * fault_address = area + (page_size * 7) / 2; |
| 527 |
|
| 528 |
#if defined(TEST_VM_MMAP_ANON) || defined(TEST_VM_MMAP_ANONYMOUS) |
| 529 |
if (area == VM_MAP_FAILED) |
| 530 |
return 1; |
| 531 |
|
| 532 |
if (vm_release((char *)area, area_size) < 0) |
| 533 |
return 1; |
| 534 |
|
| 535 |
return 0; |
| 536 |
#endif |
| 537 |
|
| 538 |
#if defined(TEST_VM_PROT_NONE_READ) || defined(TEST_VM_PROT_NONE_WRITE) |
| 539 |
if (area == VM_MAP_FAILED) |
| 540 |
return 0; |
| 541 |
|
| 542 |
if (vm_protect(page_align(fault_address), page_size, VM_PAGE_NOACCESS) < 0) |
| 543 |
return 0; |
| 544 |
#endif |
| 545 |
|
| 546 |
#if defined(TEST_VM_PROT_RDWR_WRITE) |
| 547 |
if (area == VM_MAP_FAILED) |
| 548 |
return 1; |
| 549 |
|
| 550 |
if (vm_protect(page_align(fault_address), page_size, VM_PAGE_READ) < 0) |
| 551 |
return 1; |
| 552 |
|
| 553 |
if (vm_protect(page_align(fault_address), page_size, VM_PAGE_READ | VM_PAGE_WRITE) < 0) |
| 554 |
return 1; |
| 555 |
#endif |
| 556 |
|
| 557 |
#if defined(TEST_VM_PROT_READ_WRITE) |
| 558 |
if (vm_protect(page_align(fault_address), page_size, VM_PAGE_READ) < 0) |
| 559 |
return 0; |
| 560 |
#endif |
| 561 |
|
| 562 |
#if defined(TEST_VM_PROT_NONE_READ) |
| 563 |
// this should cause a core dump |
| 564 |
char foo = *fault_address; |
| 565 |
return 0; |
| 566 |
#endif |
| 567 |
|
| 568 |
#if defined(TEST_VM_PROT_NONE_WRITE) || defined(TEST_VM_PROT_READ_WRITE) |
| 569 |
// this should cause a core dump |
| 570 |
*fault_address = 'z'; |
| 571 |
return 0; |
| 572 |
#endif |
| 573 |
|
| 574 |
#if defined(TEST_VM_PROT_RDWR_WRITE) |
| 575 |
// this should not cause a core dump |
| 576 |
*fault_address = 'z'; |
| 577 |
return 0; |
| 578 |
#endif |
| 579 |
} |
| 580 |
#endif |
