1 /* 2 * OS includes and handling of OS dependencies 3 * 4 * This header exists to pull in some common system headers that 5 * most code in QEMU will want, and to fix up some possible issues with 6 * it (missing defines, Windows weirdness, and so on). 7 * 8 * To avoid getting into possible circular include dependencies, this 9 * file should not include any other QEMU headers, with the exceptions 10 * of config-host.h, config-target.h, qemu/compiler.h, 11 * sysemu/os-posix.h, sysemu/os-win32.h, glib-compat.h and 12 * qemu/typedefs.h, all of which are doing a similar job to this file 13 * and are under similar constraints. 14 * 15 * This header also contains prototypes for functions defined in 16 * os-*.c and util/oslib-*.c; those would probably be better split 17 * out into separate header files. 18 * 19 * In an ideal world this header would contain only: 20 * (1) things which everybody needs 21 * (2) things without which code would work on most platforms but 22 * fail to compile or misbehave on a minority of host OSes 23 * 24 * This work is licensed under the terms of the GNU GPL, version 2 or later. 25 * See the COPYING file in the top-level directory. 26 */ 27 #ifndef QEMU_OSDEP_H 28 #define QEMU_OSDEP_H 29 30 #include "config-host.h" 31 #ifdef NEED_CPU_H 32 #include CONFIG_TARGET 33 #else 34 #include "exec/poison.h" 35 #endif 36 37 /* 38 * HOST_WORDS_BIGENDIAN was replaced with HOST_BIG_ENDIAN. Prevent it from 39 * creeping back in. 40 */ 41 #pragma GCC poison HOST_WORDS_BIGENDIAN 42 43 /* 44 * TARGET_WORDS_BIGENDIAN was replaced with TARGET_BIG_ENDIAN. Prevent it from 45 * creeping back in. 46 */ 47 #pragma GCC poison TARGET_WORDS_BIGENDIAN 48 49 #include "qemu/compiler.h" 50 51 /* Older versions of C++ don't get definitions of various macros from 52 * stdlib.h unless we define these macros before first inclusion of 53 * that system header. 54 */ 55 #ifndef __STDC_CONSTANT_MACROS 56 #define __STDC_CONSTANT_MACROS 57 #endif 58 #ifndef __STDC_LIMIT_MACROS 59 #define __STDC_LIMIT_MACROS 60 #endif 61 #ifndef __STDC_FORMAT_MACROS 62 #define __STDC_FORMAT_MACROS 63 #endif 64 65 /* The following block of code temporarily renames the daemon() function so the 66 * compiler does not see the warning associated with it in stdlib.h on OSX 67 */ 68 #ifdef __APPLE__ 69 #define daemon qemu_fake_daemon_function 70 #include <stdlib.h> 71 #undef daemon 72 QEMU_EXTERN_C int daemon(int, int); 73 #endif 74 75 #ifdef _WIN32 76 /* as defined in sdkddkver.h */ 77 #ifndef _WIN32_WINNT 78 #define _WIN32_WINNT 0x0600 /* Vista */ 79 #endif 80 /* reduces the number of implicitly included headers */ 81 #ifndef WIN32_LEAN_AND_MEAN 82 #define WIN32_LEAN_AND_MEAN 83 #endif 84 #endif 85 86 /* enable C99/POSIX format strings (needs mingw32-runtime 3.15 or later) */ 87 #ifdef __MINGW32__ 88 #define __USE_MINGW_ANSI_STDIO 1 89 #endif 90 91 #include <stdarg.h> 92 #include <stddef.h> 93 #include <stdbool.h> 94 #include <stdint.h> 95 #include <sys/types.h> 96 #include <stdlib.h> 97 #include <stdio.h> 98 99 #include <string.h> 100 #include <strings.h> 101 #include <inttypes.h> 102 #include <limits.h> 103 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r 104 * function availability on recentish Mingw-w64 platforms. */ 105 #include <unistd.h> 106 #include <time.h> 107 #include <ctype.h> 108 #include <errno.h> 109 #include <fcntl.h> 110 #include <getopt.h> 111 #include <sys/stat.h> 112 #include <sys/time.h> 113 #include <assert.h> 114 /* setjmp must be declared before sysemu/os-win32.h 115 * because it is redefined there. */ 116 #include <setjmp.h> 117 #include <signal.h> 118 119 #ifdef CONFIG_IOVEC 120 #include <sys/uio.h> 121 #endif 122 123 #if defined(__linux__) && defined(__sparc__) 124 /* The SPARC definition of QEMU_VMALLOC_ALIGN needs SHMLBA */ 125 #include <sys/shm.h> 126 #endif 127 128 #ifndef _WIN32 129 #include <sys/wait.h> 130 #else 131 #define WIFEXITED(x) 1 132 #define WEXITSTATUS(x) (x) 133 #endif 134 135 #ifdef __APPLE__ 136 #include <AvailabilityMacros.h> 137 #endif 138 139 /* 140 * This is somewhat like a system header; it must be outside any extern "C" 141 * block because it includes system headers itself, including glib.h, 142 * which will not compile if inside an extern "C" block. 143 */ 144 #include "glib-compat.h" 145 146 #ifdef _WIN32 147 #include "sysemu/os-win32.h" 148 #endif 149 150 #ifdef CONFIG_POSIX 151 #include "sysemu/os-posix.h" 152 #endif 153 154 #ifdef __cplusplus 155 extern "C" { 156 #endif 157 158 #include "qemu/typedefs.h" 159 160 /* 161 * For mingw, as of v6.0.0, the function implementing the assert macro is 162 * not marked as noreturn, so the compiler cannot delete code following an 163 * assert(false) as unused. We rely on this within the code base to delete 164 * code that is unreachable when features are disabled. 165 * All supported versions of Glib's g_assert() satisfy this requirement. 166 */ 167 #ifdef __MINGW32__ 168 #undef assert 169 #define assert(x) g_assert(x) 170 #endif 171 172 /** 173 * qemu_build_not_reached() 174 * 175 * The compiler, during optimization, is expected to prove that a call 176 * to this function cannot be reached and remove it. If the compiler 177 * supports QEMU_ERROR, this will be reported at compile time; otherwise 178 * this will be reported at link time due to the missing symbol. 179 */ 180 extern G_NORETURN 181 void QEMU_ERROR("code path is reachable") 182 qemu_build_not_reached_always(void); 183 #if defined(__OPTIMIZE__) && !defined(__NO_INLINE__) 184 #define qemu_build_not_reached() qemu_build_not_reached_always() 185 #else 186 #define qemu_build_not_reached() g_assert_not_reached() 187 #endif 188 189 /* 190 * According to waitpid man page: 191 * WCOREDUMP 192 * This macro is not specified in POSIX.1-2001 and is not 193 * available on some UNIX implementations (e.g., AIX, SunOS). 194 * Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif. 195 */ 196 #ifndef WCOREDUMP 197 #define WCOREDUMP(status) 0 198 #endif 199 /* 200 * We have a lot of unaudited code that may fail in strange ways, or 201 * even be a security risk during migration, if you disable assertions 202 * at compile-time. You may comment out these safety checks if you 203 * absolutely want to disable assertion overhead, but it is not 204 * supported upstream so the risk is all yours. Meanwhile, please 205 * submit patches to remove any side-effects inside an assertion, or 206 * fixing error handling that should use Error instead of assert. 207 */ 208 #ifdef NDEBUG 209 #error building with NDEBUG is not supported 210 #endif 211 #ifdef G_DISABLE_ASSERT 212 #error building with G_DISABLE_ASSERT is not supported 213 #endif 214 215 #ifndef O_LARGEFILE 216 #define O_LARGEFILE 0 217 #endif 218 #ifndef O_BINARY 219 #define O_BINARY 0 220 #endif 221 #ifndef MAP_ANONYMOUS 222 #define MAP_ANONYMOUS MAP_ANON 223 #endif 224 #ifndef MAP_FIXED_NOREPLACE 225 #define MAP_FIXED_NOREPLACE 0 226 #endif 227 #ifndef MAP_NORESERVE 228 #define MAP_NORESERVE 0 229 #endif 230 #ifndef ENOMEDIUM 231 #define ENOMEDIUM ENODEV 232 #endif 233 #if !defined(ENOTSUP) 234 #define ENOTSUP 4096 235 #endif 236 #if !defined(ECANCELED) 237 #define ECANCELED 4097 238 #endif 239 #if !defined(EMEDIUMTYPE) 240 #define EMEDIUMTYPE 4098 241 #endif 242 #if !defined(ESHUTDOWN) 243 #define ESHUTDOWN 4099 244 #endif 245 246 #define TFR(expr) do { if ((expr) != -1) break; } while (errno == EINTR) 247 248 /* time_t may be either 32 or 64 bits depending on the host OS, and 249 * can be either signed or unsigned, so we can't just hardcode a 250 * specific maximum value. This is not a C preprocessor constant, 251 * so you can't use TIME_MAX in an #ifdef, but for our purposes 252 * this isn't a problem. 253 */ 254 255 /* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from 256 * Gnulib, and are under the LGPL v2.1 or (at your option) any 257 * later version. 258 */ 259 260 /* True if the real type T is signed. */ 261 #define TYPE_SIGNED(t) (!((t)0 < (t)-1)) 262 263 /* The width in bits of the integer type or expression T. 264 * Padding bits are not supported. 265 */ 266 #define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT) 267 268 /* The maximum and minimum values for the integer type T. */ 269 #define TYPE_MAXIMUM(t) \ 270 ((t) (!TYPE_SIGNED(t) \ 271 ? (t)-1 \ 272 : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1))) 273 274 #ifndef TIME_MAX 275 #define TIME_MAX TYPE_MAXIMUM(time_t) 276 #endif 277 278 /* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with 279 * the wrong type. Our replacement isn't usable in preprocessor 280 * expressions, but it is sufficient for our needs. */ 281 #ifdef HAVE_BROKEN_SIZE_MAX 282 #undef SIZE_MAX 283 #define SIZE_MAX ((size_t)-1) 284 #endif 285 286 /* 287 * Two variations of MIN/MAX macros. The first is for runtime use, and 288 * evaluates arguments only once (so it is safe even with side 289 * effects), but will not work in constant contexts (such as array 290 * size declarations) because of the '{}'. The second is for constant 291 * expression use, where evaluating arguments twice is safe because 292 * the result is going to be constant anyway, but will not work in a 293 * runtime context because of a void expression where a value is 294 * expected. Thus, both gcc and clang will fail to compile if you use 295 * the wrong macro (even if the error may seem a bit cryptic). 296 * 297 * Note that neither form is usable as an #if condition; if you truly 298 * need to write conditional code that depends on a minimum or maximum 299 * determined by the pre-processor instead of the compiler, you'll 300 * have to open-code it. Sadly, Coverity is severely confused by the 301 * constant variants, so we have to dumb things down there. 302 */ 303 #undef MIN 304 #define MIN(a, b) \ 305 ({ \ 306 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 307 _a < _b ? _a : _b; \ 308 }) 309 #undef MAX 310 #define MAX(a, b) \ 311 ({ \ 312 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 313 _a > _b ? _a : _b; \ 314 }) 315 316 #ifdef __COVERITY__ 317 # define MIN_CONST(a, b) ((a) < (b) ? (a) : (b)) 318 # define MAX_CONST(a, b) ((a) > (b) ? (a) : (b)) 319 #else 320 # define MIN_CONST(a, b) \ 321 __builtin_choose_expr( \ 322 __builtin_constant_p(a) && __builtin_constant_p(b), \ 323 (a) < (b) ? (a) : (b), \ 324 ((void)0)) 325 # define MAX_CONST(a, b) \ 326 __builtin_choose_expr( \ 327 __builtin_constant_p(a) && __builtin_constant_p(b), \ 328 (a) > (b) ? (a) : (b), \ 329 ((void)0)) 330 #endif 331 332 /* 333 * Minimum function that returns zero only if both values are zero. 334 * Intended for use with unsigned values only. 335 */ 336 #ifndef MIN_NON_ZERO 337 #define MIN_NON_ZERO(a, b) \ 338 ({ \ 339 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \ 340 _a == 0 ? _b : (_b == 0 || _b > _a) ? _a : _b; \ 341 }) 342 #endif 343 344 /* 345 * Round number down to multiple. Safe when m is not a power of 2 (see 346 * ROUND_DOWN for a faster version when a power of 2 is guaranteed). 347 */ 348 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m)) 349 350 /* 351 * Round number up to multiple. Safe when m is not a power of 2 (see 352 * ROUND_UP for a faster version when a power of 2 is guaranteed). 353 */ 354 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m)) 355 356 /* Check if n is a multiple of m */ 357 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0) 358 359 /* n-byte align pointer down */ 360 #define QEMU_ALIGN_PTR_DOWN(p, n) \ 361 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n))) 362 363 /* n-byte align pointer up */ 364 #define QEMU_ALIGN_PTR_UP(p, n) \ 365 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n))) 366 367 /* Check if pointer p is n-bytes aligned */ 368 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n)) 369 370 /* 371 * Round number down to multiple. Requires that d be a power of 2 (see 372 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 373 * numbers); works even if d is a smaller type than n. 374 */ 375 #ifndef ROUND_DOWN 376 #define ROUND_DOWN(n, d) ((n) & -(0 ? (n) : (d))) 377 #endif 378 379 /* 380 * Round number up to multiple. Requires that d be a power of 2 (see 381 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 382 * numbers); works even if d is a smaller type than n. 383 */ 384 #ifndef ROUND_UP 385 #define ROUND_UP(n, d) ROUND_DOWN((n) + (d) - 1, (d)) 386 #endif 387 388 #ifndef DIV_ROUND_UP 389 #define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) 390 #endif 391 392 /* 393 * &(x)[0] is always a pointer - if it's same type as x then the argument is a 394 * pointer, not an array. 395 */ 396 #define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \ 397 typeof(&(x)[0]))) 398 #ifndef ARRAY_SIZE 399 #define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \ 400 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x))) 401 #endif 402 403 int qemu_daemon(int nochdir, int noclose); 404 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared, 405 bool noreserve); 406 void qemu_anon_ram_free(void *ptr, size_t size); 407 408 #ifdef _WIN32 409 #define HAVE_CHARDEV_SERIAL 1 410 #elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 411 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ 412 || defined(__GLIBC__) || defined(__APPLE__) 413 #define HAVE_CHARDEV_SERIAL 1 414 #endif 415 416 #if defined(__linux__) || defined(__FreeBSD__) || \ 417 defined(__FreeBSD_kernel__) || defined(__DragonFly__) 418 #define HAVE_CHARDEV_PARPORT 1 419 #endif 420 421 #if defined(__HAIKU__) 422 #define SIGIO SIGPOLL 423 #endif 424 425 #ifdef HAVE_MADVISE_WITHOUT_PROTOTYPE 426 /* 427 * See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for discussion 428 * about Solaris missing the madvise() prototype. 429 */ 430 extern int madvise(char *, size_t, int); 431 #endif 432 433 #if defined(CONFIG_LINUX) 434 #ifndef BUS_MCEERR_AR 435 #define BUS_MCEERR_AR 4 436 #endif 437 #ifndef BUS_MCEERR_AO 438 #define BUS_MCEERR_AO 5 439 #endif 440 #endif 441 442 #if defined(__linux__) && \ 443 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \ 444 || defined(__powerpc64__)) 445 /* Use 2 MiB alignment so transparent hugepages can be used by KVM. 446 Valgrind does not support alignments larger than 1 MiB, 447 therefore we need special code which handles running on Valgrind. */ 448 # define QEMU_VMALLOC_ALIGN (512 * 4096) 449 #elif defined(__linux__) && defined(__s390x__) 450 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */ 451 # define QEMU_VMALLOC_ALIGN (256 * 4096) 452 #elif defined(__linux__) && defined(__sparc__) 453 # define QEMU_VMALLOC_ALIGN MAX(qemu_real_host_page_size(), SHMLBA) 454 #else 455 # define QEMU_VMALLOC_ALIGN qemu_real_host_page_size() 456 #endif 457 458 #ifdef CONFIG_POSIX 459 struct qemu_signalfd_siginfo { 460 uint32_t ssi_signo; /* Signal number */ 461 int32_t ssi_errno; /* Error number (unused) */ 462 int32_t ssi_code; /* Signal code */ 463 uint32_t ssi_pid; /* PID of sender */ 464 uint32_t ssi_uid; /* Real UID of sender */ 465 int32_t ssi_fd; /* File descriptor (SIGIO) */ 466 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */ 467 uint32_t ssi_band; /* Band event (SIGIO) */ 468 uint32_t ssi_overrun; /* POSIX timer overrun count */ 469 uint32_t ssi_trapno; /* Trap number that caused signal */ 470 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */ 471 int32_t ssi_int; /* Integer sent by sigqueue(2) */ 472 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */ 473 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */ 474 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */ 475 uint64_t ssi_addr; /* Address that generated signal 476 (for hardware-generated signals) */ 477 uint8_t pad[48]; /* Pad size to 128 bytes (allow for 478 additional fields in the future) */ 479 }; 480 481 int qemu_signalfd(const sigset_t *mask); 482 void sigaction_invoke(struct sigaction *action, 483 struct qemu_signalfd_siginfo *info); 484 #endif 485 486 /* 487 * Don't introduce new usage of this function, prefer the following 488 * qemu_open/qemu_create that take an "Error **errp" 489 */ 490 int qemu_open_old(const char *name, int flags, ...); 491 int qemu_open(const char *name, int flags, Error **errp); 492 int qemu_create(const char *name, int flags, mode_t mode, Error **errp); 493 int qemu_close(int fd); 494 int qemu_unlink(const char *name); 495 #ifndef _WIN32 496 int qemu_dup_flags(int fd, int flags); 497 int qemu_dup(int fd); 498 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); 499 int qemu_unlock_fd(int fd, int64_t start, int64_t len); 500 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); 501 bool qemu_has_ofd_lock(void); 502 #endif 503 504 #if defined(__HAIKU__) && defined(__i386__) 505 #define FMT_pid "%ld" 506 #elif defined(WIN64) 507 #define FMT_pid "%" PRId64 508 #else 509 #define FMT_pid "%d" 510 #endif 511 512 bool qemu_write_pidfile(const char *pidfile, Error **errp); 513 514 int qemu_get_thread_id(void); 515 516 #ifndef CONFIG_IOVEC 517 struct iovec { 518 void *iov_base; 519 size_t iov_len; 520 }; 521 /* 522 * Use the same value as Linux for now. 523 */ 524 #define IOV_MAX 1024 525 526 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt); 527 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); 528 #endif 529 530 #ifdef _WIN32 531 static inline void qemu_timersub(const struct timeval *val1, 532 const struct timeval *val2, 533 struct timeval *res) 534 { 535 res->tv_sec = val1->tv_sec - val2->tv_sec; 536 if (val1->tv_usec < val2->tv_usec) { 537 res->tv_sec--; 538 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000; 539 } else { 540 res->tv_usec = val1->tv_usec - val2->tv_usec; 541 } 542 } 543 #else 544 #define qemu_timersub timersub 545 #endif 546 547 ssize_t qemu_write_full(int fd, const void *buf, size_t count) 548 G_GNUC_WARN_UNUSED_RESULT; 549 550 void qemu_set_cloexec(int fd); 551 552 /* Return a dynamically allocated directory path that is appropriate for storing 553 * local state. 554 * 555 * The caller is responsible for releasing the value returned with g_free() 556 * after use. 557 */ 558 char *qemu_get_local_state_dir(void); 559 560 /* Find program directory, and save it for later usage with 561 * qemu_get_exec_dir(). 562 * Try OS specific API first, if not working, parse from argv0. */ 563 void qemu_init_exec_dir(const char *argv0); 564 565 /* Get the saved exec dir. */ 566 const char *qemu_get_exec_dir(void); 567 568 /** 569 * qemu_getauxval: 570 * @type: the auxiliary vector key to lookup 571 * 572 * Search the auxiliary vector for @type, returning the value 573 * or 0 if @type is not present. 574 */ 575 unsigned long qemu_getauxval(unsigned long type); 576 577 void qemu_set_tty_echo(int fd, bool echo); 578 579 void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, 580 Error **errp); 581 582 /** 583 * qemu_get_pid_name: 584 * @pid: pid of a process 585 * 586 * For given @pid fetch its name. Caller is responsible for 587 * freeing the string when no longer needed. 588 * Returns allocated string on success, NULL on failure. 589 */ 590 char *qemu_get_pid_name(pid_t pid); 591 592 /** 593 * qemu_fork: 594 * 595 * A version of fork that avoids signal handler race 596 * conditions that can lead to child process getting 597 * signals that are otherwise only expected by the 598 * parent. It also resets all signal handlers to the 599 * default settings. 600 * 601 * Returns 0 to child process, pid number to parent 602 * or -1 on failure. 603 */ 604 pid_t qemu_fork(Error **errp); 605 606 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even 607 * when intptr_t is 32-bit and we are aligning a long long. 608 */ 609 static inline uintptr_t qemu_real_host_page_size(void) 610 { 611 return getpagesize(); 612 } 613 614 static inline intptr_t qemu_real_host_page_mask(void) 615 { 616 return -(intptr_t)qemu_real_host_page_size(); 617 } 618 619 /* 620 * After using getopt or getopt_long, if you need to parse another set 621 * of options, then you must reset optind. Unfortunately the way to 622 * do this varies between implementations of getopt. 623 */ 624 static inline void qemu_reset_optind(void) 625 { 626 #ifdef HAVE_OPTRESET 627 optind = 1; 628 optreset = 1; 629 #else 630 optind = 0; 631 #endif 632 } 633 634 int qemu_fdatasync(int fd); 635 636 /** 637 * Sync changes made to the memory mapped file back to the backing 638 * storage. For POSIX compliant systems this will fallback 639 * to regular msync call. Otherwise it will trigger whole file sync 640 * (including the metadata case there is no support to skip that otherwise) 641 * 642 * @addr - start of the memory area to be synced 643 * @length - length of the are to be synced 644 * @fd - file descriptor for the file to be synced 645 * (mandatory only for POSIX non-compliant systems) 646 */ 647 int qemu_msync(void *addr, size_t length, int fd); 648 649 /** 650 * qemu_get_host_physmem: 651 * 652 * Operating system agnostic way of querying host memory. 653 * 654 * Returns amount of physical memory on the system. This is purely 655 * advisery and may return 0 if we can't work it out. At the other 656 * end we saturate to SIZE_MAX if you are lucky enough to have that 657 * much memory. 658 */ 659 size_t qemu_get_host_physmem(void); 660 661 /* 662 * Toggle write/execute on the pages marked MAP_JIT 663 * for the current thread. 664 */ 665 #if defined(MAC_OS_VERSION_11_0) && \ 666 MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_VERSION_11_0 667 static inline void qemu_thread_jit_execute(void) 668 { 669 pthread_jit_write_protect_np(true); 670 } 671 672 static inline void qemu_thread_jit_write(void) 673 { 674 pthread_jit_write_protect_np(false); 675 } 676 #else 677 static inline void qemu_thread_jit_write(void) {} 678 static inline void qemu_thread_jit_execute(void) {} 679 #endif 680 681 /** 682 * Platforms which do not support system() return ENOSYS 683 */ 684 #ifndef HAVE_SYSTEM_FUNCTION 685 #define system platform_does_not_support_system 686 static inline int platform_does_not_support_system(const char *command) 687 { 688 errno = ENOSYS; 689 return -1; 690 } 691 #endif /* !HAVE_SYSTEM_FUNCTION */ 692 693 #ifdef __cplusplus 694 } 695 #endif 696 697 #endif 698