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.h" 33 #else 34 #include "exec/poison.h" 35 #endif 36 #include "qemu/compiler.h" 37 38 /* Older versions of C++ don't get definitions of various macros from 39 * stdlib.h unless we define these macros before first inclusion of 40 * that system header. 41 */ 42 #ifndef __STDC_CONSTANT_MACROS 43 #define __STDC_CONSTANT_MACROS 44 #endif 45 #ifndef __STDC_LIMIT_MACROS 46 #define __STDC_LIMIT_MACROS 47 #endif 48 #ifndef __STDC_FORMAT_MACROS 49 #define __STDC_FORMAT_MACROS 50 #endif 51 52 /* The following block of code temporarily renames the daemon() function so the 53 * compiler does not see the warning associated with it in stdlib.h on OSX 54 */ 55 #ifdef __APPLE__ 56 #define daemon qemu_fake_daemon_function 57 #include <stdlib.h> 58 #undef daemon 59 extern int daemon(int, int); 60 #endif 61 62 #include <stdarg.h> 63 #include <stddef.h> 64 #include <stdbool.h> 65 #include <stdint.h> 66 #include <sys/types.h> 67 #include <stdlib.h> 68 #include <stdio.h> 69 #include <string.h> 70 #include <strings.h> 71 #include <inttypes.h> 72 #include <limits.h> 73 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r 74 * function availability on recentish Mingw-w64 platforms. */ 75 #include <unistd.h> 76 #include <time.h> 77 #include <ctype.h> 78 #include <errno.h> 79 #include <fcntl.h> 80 #include <sys/stat.h> 81 #include <sys/time.h> 82 #include <assert.h> 83 /* setjmp must be declared before sysemu/os-win32.h 84 * because it is redefined there. */ 85 #include <setjmp.h> 86 #include <signal.h> 87 88 #ifdef __OpenBSD__ 89 #include <sys/signal.h> 90 #endif 91 92 #ifndef _WIN32 93 #include <sys/wait.h> 94 #else 95 #define WIFEXITED(x) 1 96 #define WEXITSTATUS(x) (x) 97 #endif 98 99 #ifdef _WIN32 100 #include "sysemu/os-win32.h" 101 #endif 102 103 #ifdef CONFIG_POSIX 104 #include "sysemu/os-posix.h" 105 #endif 106 107 #include "glib-compat.h" 108 #include "qemu/typedefs.h" 109 110 /* 111 * We have a lot of unaudited code that may fail in strange ways, or 112 * even be a security risk during migration, if you disable assertions 113 * at compile-time. You may comment out these safety checks if you 114 * absolutely want to disable assertion overhead, but it is not 115 * supported upstream so the risk is all yours. Meanwhile, please 116 * submit patches to remove any side-effects inside an assertion, or 117 * fixing error handling that should use Error instead of assert. 118 */ 119 #ifdef NDEBUG 120 #error building with NDEBUG is not supported 121 #endif 122 #ifdef G_DISABLE_ASSERT 123 #error building with G_DISABLE_ASSERT is not supported 124 #endif 125 126 #ifndef O_LARGEFILE 127 #define O_LARGEFILE 0 128 #endif 129 #ifndef O_BINARY 130 #define O_BINARY 0 131 #endif 132 #ifndef MAP_ANONYMOUS 133 #define MAP_ANONYMOUS MAP_ANON 134 #endif 135 #ifndef ENOMEDIUM 136 #define ENOMEDIUM ENODEV 137 #endif 138 #if !defined(ENOTSUP) 139 #define ENOTSUP 4096 140 #endif 141 #if !defined(ECANCELED) 142 #define ECANCELED 4097 143 #endif 144 #if !defined(EMEDIUMTYPE) 145 #define EMEDIUMTYPE 4098 146 #endif 147 #if !defined(ESHUTDOWN) 148 #define ESHUTDOWN 4099 149 #endif 150 151 /* time_t may be either 32 or 64 bits depending on the host OS, and 152 * can be either signed or unsigned, so we can't just hardcode a 153 * specific maximum value. This is not a C preprocessor constant, 154 * so you can't use TIME_MAX in an #ifdef, but for our purposes 155 * this isn't a problem. 156 */ 157 158 /* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from 159 * Gnulib, and are under the LGPL v2.1 or (at your option) any 160 * later version. 161 */ 162 163 /* True if the real type T is signed. */ 164 #define TYPE_SIGNED(t) (!((t)0 < (t)-1)) 165 166 /* The width in bits of the integer type or expression T. 167 * Padding bits are not supported. 168 */ 169 #define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT) 170 171 /* The maximum and minimum values for the integer type T. */ 172 #define TYPE_MAXIMUM(t) \ 173 ((t) (!TYPE_SIGNED(t) \ 174 ? (t)-1 \ 175 : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1))) 176 177 #ifndef TIME_MAX 178 #define TIME_MAX TYPE_MAXIMUM(time_t) 179 #endif 180 181 /* HOST_LONG_BITS is the size of a native pointer in bits. */ 182 #if UINTPTR_MAX == UINT32_MAX 183 # define HOST_LONG_BITS 32 184 #elif UINTPTR_MAX == UINT64_MAX 185 # define HOST_LONG_BITS 64 186 #else 187 # error Unknown pointer size 188 #endif 189 190 /* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with 191 * the wrong type. Our replacement isn't usable in preprocessor 192 * expressions, but it is sufficient for our needs. */ 193 #if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX 194 #undef SIZE_MAX 195 #define SIZE_MAX ((size_t)-1) 196 #endif 197 198 #ifndef MIN 199 #define MIN(a, b) (((a) < (b)) ? (a) : (b)) 200 #endif 201 #ifndef MAX 202 #define MAX(a, b) (((a) > (b)) ? (a) : (b)) 203 #endif 204 205 /* Minimum function that returns zero only iff both values are zero. 206 * Intended for use with unsigned values only. */ 207 #ifndef MIN_NON_ZERO 208 #define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \ 209 ((b) == 0 ? (a) : (MIN(a, b)))) 210 #endif 211 212 /* Round number down to multiple */ 213 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m)) 214 215 /* Round number up to multiple. Safe when m is not a power of 2 (see 216 * ROUND_UP for a faster version when a power of 2 is guaranteed) */ 217 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m)) 218 219 /* Check if n is a multiple of m */ 220 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0) 221 222 /* n-byte align pointer down */ 223 #define QEMU_ALIGN_PTR_DOWN(p, n) \ 224 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n))) 225 226 /* n-byte align pointer up */ 227 #define QEMU_ALIGN_PTR_UP(p, n) \ 228 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n))) 229 230 /* Check if pointer p is n-bytes aligned */ 231 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n)) 232 233 /* Round number up to multiple. Requires that d be a power of 2 (see 234 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 235 * numbers); works even if d is a smaller type than n. */ 236 #ifndef ROUND_UP 237 #define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d))) 238 #endif 239 240 #ifndef DIV_ROUND_UP 241 #define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) 242 #endif 243 244 /* 245 * &(x)[0] is always a pointer - if it's same type as x then the argument is a 246 * pointer, not an array. 247 */ 248 #define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \ 249 typeof(&(x)[0]))) 250 #ifndef ARRAY_SIZE 251 #define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \ 252 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x))) 253 #endif 254 255 int qemu_daemon(int nochdir, int noclose); 256 void *qemu_try_memalign(size_t alignment, size_t size); 257 void *qemu_memalign(size_t alignment, size_t size); 258 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared); 259 void qemu_vfree(void *ptr); 260 void qemu_anon_ram_free(void *ptr, size_t size); 261 262 #define QEMU_MADV_INVALID -1 263 264 #if defined(CONFIG_MADVISE) 265 266 #define QEMU_MADV_WILLNEED MADV_WILLNEED 267 #define QEMU_MADV_DONTNEED MADV_DONTNEED 268 #ifdef MADV_DONTFORK 269 #define QEMU_MADV_DONTFORK MADV_DONTFORK 270 #else 271 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 272 #endif 273 #ifdef MADV_MERGEABLE 274 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE 275 #else 276 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 277 #endif 278 #ifdef MADV_UNMERGEABLE 279 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE 280 #else 281 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 282 #endif 283 #ifdef MADV_DODUMP 284 #define QEMU_MADV_DODUMP MADV_DODUMP 285 #else 286 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 287 #endif 288 #ifdef MADV_DONTDUMP 289 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP 290 #else 291 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 292 #endif 293 #ifdef MADV_HUGEPAGE 294 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE 295 #else 296 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 297 #endif 298 #ifdef MADV_NOHUGEPAGE 299 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE 300 #else 301 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 302 #endif 303 #ifdef MADV_REMOVE 304 #define QEMU_MADV_REMOVE MADV_REMOVE 305 #else 306 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 307 #endif 308 309 #elif defined(CONFIG_POSIX_MADVISE) 310 311 #define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED 312 #define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED 313 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 314 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 315 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 316 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 317 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 318 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 319 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 320 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 321 322 #else /* no-op */ 323 324 #define QEMU_MADV_WILLNEED QEMU_MADV_INVALID 325 #define QEMU_MADV_DONTNEED QEMU_MADV_INVALID 326 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 327 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 328 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 329 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 330 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 331 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 332 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 333 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 334 335 #endif 336 337 #ifdef _WIN32 338 #define HAVE_CHARDEV_SERIAL 1 339 #elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 340 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ 341 || defined(__GLIBC__) 342 #define HAVE_CHARDEV_SERIAL 1 343 #endif 344 345 #if defined(__linux__) || defined(__FreeBSD__) || \ 346 defined(__FreeBSD_kernel__) || defined(__DragonFly__) 347 #define HAVE_CHARDEV_PARPORT 1 348 #endif 349 350 #if defined(CONFIG_LINUX) 351 #ifndef BUS_MCEERR_AR 352 #define BUS_MCEERR_AR 4 353 #endif 354 #ifndef BUS_MCEERR_AO 355 #define BUS_MCEERR_AO 5 356 #endif 357 #endif 358 359 #if defined(__linux__) && \ 360 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__)) 361 /* Use 2 MiB alignment so transparent hugepages can be used by KVM. 362 Valgrind does not support alignments larger than 1 MiB, 363 therefore we need special code which handles running on Valgrind. */ 364 # define QEMU_VMALLOC_ALIGN (512 * 4096) 365 #elif defined(__linux__) && defined(__s390x__) 366 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */ 367 # define QEMU_VMALLOC_ALIGN (256 * 4096) 368 #elif defined(__linux__) && defined(__sparc__) 369 #include <sys/shm.h> 370 # define QEMU_VMALLOC_ALIGN MAX(getpagesize(), SHMLBA) 371 #else 372 # define QEMU_VMALLOC_ALIGN getpagesize() 373 #endif 374 375 #ifdef CONFIG_POSIX 376 struct qemu_signalfd_siginfo { 377 uint32_t ssi_signo; /* Signal number */ 378 int32_t ssi_errno; /* Error number (unused) */ 379 int32_t ssi_code; /* Signal code */ 380 uint32_t ssi_pid; /* PID of sender */ 381 uint32_t ssi_uid; /* Real UID of sender */ 382 int32_t ssi_fd; /* File descriptor (SIGIO) */ 383 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */ 384 uint32_t ssi_band; /* Band event (SIGIO) */ 385 uint32_t ssi_overrun; /* POSIX timer overrun count */ 386 uint32_t ssi_trapno; /* Trap number that caused signal */ 387 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */ 388 int32_t ssi_int; /* Integer sent by sigqueue(2) */ 389 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */ 390 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */ 391 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */ 392 uint64_t ssi_addr; /* Address that generated signal 393 (for hardware-generated signals) */ 394 uint8_t pad[48]; /* Pad size to 128 bytes (allow for 395 additional fields in the future) */ 396 }; 397 398 int qemu_signalfd(const sigset_t *mask); 399 void sigaction_invoke(struct sigaction *action, 400 struct qemu_signalfd_siginfo *info); 401 #endif 402 403 int qemu_madvise(void *addr, size_t len, int advice); 404 int qemu_mprotect_rwx(void *addr, size_t size); 405 int qemu_mprotect_none(void *addr, size_t size); 406 407 int qemu_open(const char *name, int flags, ...); 408 int qemu_close(int fd); 409 #ifndef _WIN32 410 int qemu_dup(int fd); 411 #endif 412 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); 413 int qemu_unlock_fd(int fd, int64_t start, int64_t len); 414 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); 415 bool qemu_has_ofd_lock(void); 416 417 #if defined(__HAIKU__) && defined(__i386__) 418 #define FMT_pid "%ld" 419 #elif defined(WIN64) 420 #define FMT_pid "%" PRId64 421 #else 422 #define FMT_pid "%d" 423 #endif 424 425 int qemu_create_pidfile(const char *filename); 426 int qemu_get_thread_id(void); 427 428 #ifndef CONFIG_IOVEC 429 struct iovec { 430 void *iov_base; 431 size_t iov_len; 432 }; 433 /* 434 * Use the same value as Linux for now. 435 */ 436 #define IOV_MAX 1024 437 438 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt); 439 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); 440 #else 441 #include <sys/uio.h> 442 #endif 443 444 #ifdef _WIN32 445 static inline void qemu_timersub(const struct timeval *val1, 446 const struct timeval *val2, 447 struct timeval *res) 448 { 449 res->tv_sec = val1->tv_sec - val2->tv_sec; 450 if (val1->tv_usec < val2->tv_usec) { 451 res->tv_sec--; 452 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000; 453 } else { 454 res->tv_usec = val1->tv_usec - val2->tv_usec; 455 } 456 } 457 #else 458 #define qemu_timersub timersub 459 #endif 460 461 void qemu_set_cloexec(int fd); 462 463 /* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default 464 * instead of QEMU_VERSION, so setting hw_version on MachineClass 465 * is no longer mandatory. 466 * 467 * Do NOT change this string, or it will break compatibility on all 468 * machine classes that don't set hw_version. 469 */ 470 #define QEMU_HW_VERSION "2.5+" 471 472 /* QEMU "hardware version" setting. Used to replace code that exposed 473 * QEMU_VERSION to guests in the past and need to keep compatibility. 474 * Do not use qemu_hw_version() in new code. 475 */ 476 void qemu_set_hw_version(const char *); 477 const char *qemu_hw_version(void); 478 479 void fips_set_state(bool requested); 480 bool fips_get_state(void); 481 482 /* Return a dynamically allocated pathname denoting a file or directory that is 483 * appropriate for storing local state. 484 * 485 * @relative_pathname need not start with a directory separator; one will be 486 * added automatically. 487 * 488 * The caller is responsible for releasing the value returned with g_free() 489 * after use. 490 */ 491 char *qemu_get_local_state_pathname(const char *relative_pathname); 492 493 /* Find program directory, and save it for later usage with 494 * qemu_get_exec_dir(). 495 * Try OS specific API first, if not working, parse from argv0. */ 496 void qemu_init_exec_dir(const char *argv0); 497 498 /* Get the saved exec dir. 499 * Caller needs to release the returned string by g_free() */ 500 char *qemu_get_exec_dir(void); 501 502 /** 503 * qemu_getauxval: 504 * @type: the auxiliary vector key to lookup 505 * 506 * Search the auxiliary vector for @type, returning the value 507 * or 0 if @type is not present. 508 */ 509 unsigned long qemu_getauxval(unsigned long type); 510 511 void qemu_set_tty_echo(int fd, bool echo); 512 513 void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, 514 Error **errp); 515 516 /** 517 * qemu_get_pid_name: 518 * @pid: pid of a process 519 * 520 * For given @pid fetch its name. Caller is responsible for 521 * freeing the string when no longer needed. 522 * Returns allocated string on success, NULL on failure. 523 */ 524 char *qemu_get_pid_name(pid_t pid); 525 526 /** 527 * qemu_fork: 528 * 529 * A version of fork that avoids signal handler race 530 * conditions that can lead to child process getting 531 * signals that are otherwise only expected by the 532 * parent. It also resets all signal handlers to the 533 * default settings. 534 * 535 * Returns 0 to child process, pid number to parent 536 * or -1 on failure. 537 */ 538 pid_t qemu_fork(Error **errp); 539 540 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even 541 * when intptr_t is 32-bit and we are aligning a long long. 542 */ 543 extern uintptr_t qemu_real_host_page_size; 544 extern intptr_t qemu_real_host_page_mask; 545 546 extern int qemu_icache_linesize; 547 extern int qemu_dcache_linesize; 548 549 #endif 550