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 #ifndef TIME_MAX 151 #define TIME_MAX LONG_MAX 152 #endif 153 154 /* HOST_LONG_BITS is the size of a native pointer in bits. */ 155 #if UINTPTR_MAX == UINT32_MAX 156 # define HOST_LONG_BITS 32 157 #elif UINTPTR_MAX == UINT64_MAX 158 # define HOST_LONG_BITS 64 159 #else 160 # error Unknown pointer size 161 #endif 162 163 /* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with 164 * the wrong type. Our replacement isn't usable in preprocessor 165 * expressions, but it is sufficient for our needs. */ 166 #if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX 167 #undef SIZE_MAX 168 #define SIZE_MAX ((size_t)-1) 169 #endif 170 171 #ifndef MIN 172 #define MIN(a, b) (((a) < (b)) ? (a) : (b)) 173 #endif 174 #ifndef MAX 175 #define MAX(a, b) (((a) > (b)) ? (a) : (b)) 176 #endif 177 178 /* Minimum function that returns zero only iff both values are zero. 179 * Intended for use with unsigned values only. */ 180 #ifndef MIN_NON_ZERO 181 #define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \ 182 ((b) == 0 ? (a) : (MIN(a, b)))) 183 #endif 184 185 /* Round number down to multiple */ 186 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m)) 187 188 /* Round number up to multiple. Safe when m is not a power of 2 (see 189 * ROUND_UP for a faster version when a power of 2 is guaranteed) */ 190 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m)) 191 192 /* Check if n is a multiple of m */ 193 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0) 194 195 /* n-byte align pointer down */ 196 #define QEMU_ALIGN_PTR_DOWN(p, n) \ 197 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n))) 198 199 /* n-byte align pointer up */ 200 #define QEMU_ALIGN_PTR_UP(p, n) \ 201 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n))) 202 203 /* Check if pointer p is n-bytes aligned */ 204 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n)) 205 206 /* Round number up to multiple. Requires that d be a power of 2 (see 207 * QEMU_ALIGN_UP for a safer but slower version on arbitrary 208 * numbers); works even if d is a smaller type than n. */ 209 #ifndef ROUND_UP 210 #define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d))) 211 #endif 212 213 #ifndef DIV_ROUND_UP 214 #define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) 215 #endif 216 217 /* 218 * &(x)[0] is always a pointer - if it's same type as x then the argument is a 219 * pointer, not an array. 220 */ 221 #define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \ 222 typeof(&(x)[0]))) 223 #ifndef ARRAY_SIZE 224 #define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \ 225 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x))) 226 #endif 227 228 int qemu_daemon(int nochdir, int noclose); 229 void *qemu_try_memalign(size_t alignment, size_t size); 230 void *qemu_memalign(size_t alignment, size_t size); 231 void *qemu_anon_ram_alloc(size_t size, uint64_t *align); 232 void qemu_vfree(void *ptr); 233 void qemu_anon_ram_free(void *ptr, size_t size); 234 235 #define QEMU_MADV_INVALID -1 236 237 #if defined(CONFIG_MADVISE) 238 239 #define QEMU_MADV_WILLNEED MADV_WILLNEED 240 #define QEMU_MADV_DONTNEED MADV_DONTNEED 241 #ifdef MADV_DONTFORK 242 #define QEMU_MADV_DONTFORK MADV_DONTFORK 243 #else 244 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 245 #endif 246 #ifdef MADV_MERGEABLE 247 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE 248 #else 249 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 250 #endif 251 #ifdef MADV_UNMERGEABLE 252 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE 253 #else 254 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 255 #endif 256 #ifdef MADV_DODUMP 257 #define QEMU_MADV_DODUMP MADV_DODUMP 258 #else 259 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 260 #endif 261 #ifdef MADV_DONTDUMP 262 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP 263 #else 264 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 265 #endif 266 #ifdef MADV_HUGEPAGE 267 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE 268 #else 269 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 270 #endif 271 #ifdef MADV_NOHUGEPAGE 272 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE 273 #else 274 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 275 #endif 276 #ifdef MADV_REMOVE 277 #define QEMU_MADV_REMOVE MADV_REMOVE 278 #else 279 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 280 #endif 281 282 #elif defined(CONFIG_POSIX_MADVISE) 283 284 #define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED 285 #define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED 286 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 287 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 288 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 289 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 290 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 291 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 292 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 293 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 294 295 #else /* no-op */ 296 297 #define QEMU_MADV_WILLNEED QEMU_MADV_INVALID 298 #define QEMU_MADV_DONTNEED QEMU_MADV_INVALID 299 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID 300 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID 301 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID 302 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID 303 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID 304 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID 305 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID 306 #define QEMU_MADV_REMOVE QEMU_MADV_INVALID 307 308 #endif 309 310 #ifdef _WIN32 311 #define HAVE_CHARDEV_SERIAL 1 312 #elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 313 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ 314 || defined(__GLIBC__) 315 #define HAVE_CHARDEV_SERIAL 1 316 #endif 317 318 #if defined(__linux__) || defined(__FreeBSD__) || \ 319 defined(__FreeBSD_kernel__) || defined(__DragonFly__) 320 #define HAVE_CHARDEV_PARPORT 1 321 #endif 322 323 #if defined(CONFIG_LINUX) 324 #ifndef BUS_MCEERR_AR 325 #define BUS_MCEERR_AR 4 326 #endif 327 #ifndef BUS_MCEERR_AO 328 #define BUS_MCEERR_AO 5 329 #endif 330 #endif 331 332 #if defined(__linux__) && \ 333 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__)) 334 /* Use 2 MiB alignment so transparent hugepages can be used by KVM. 335 Valgrind does not support alignments larger than 1 MiB, 336 therefore we need special code which handles running on Valgrind. */ 337 # define QEMU_VMALLOC_ALIGN (512 * 4096) 338 #elif defined(__linux__) && defined(__s390x__) 339 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */ 340 # define QEMU_VMALLOC_ALIGN (256 * 4096) 341 #else 342 # define QEMU_VMALLOC_ALIGN getpagesize() 343 #endif 344 345 #ifdef CONFIG_POSIX 346 struct qemu_signalfd_siginfo { 347 uint32_t ssi_signo; /* Signal number */ 348 int32_t ssi_errno; /* Error number (unused) */ 349 int32_t ssi_code; /* Signal code */ 350 uint32_t ssi_pid; /* PID of sender */ 351 uint32_t ssi_uid; /* Real UID of sender */ 352 int32_t ssi_fd; /* File descriptor (SIGIO) */ 353 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */ 354 uint32_t ssi_band; /* Band event (SIGIO) */ 355 uint32_t ssi_overrun; /* POSIX timer overrun count */ 356 uint32_t ssi_trapno; /* Trap number that caused signal */ 357 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */ 358 int32_t ssi_int; /* Integer sent by sigqueue(2) */ 359 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */ 360 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */ 361 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */ 362 uint64_t ssi_addr; /* Address that generated signal 363 (for hardware-generated signals) */ 364 uint8_t pad[48]; /* Pad size to 128 bytes (allow for 365 additional fields in the future) */ 366 }; 367 368 int qemu_signalfd(const sigset_t *mask); 369 void sigaction_invoke(struct sigaction *action, 370 struct qemu_signalfd_siginfo *info); 371 #endif 372 373 int qemu_madvise(void *addr, size_t len, int advice); 374 375 int qemu_open(const char *name, int flags, ...); 376 int qemu_close(int fd); 377 #ifndef _WIN32 378 int qemu_dup(int fd); 379 #endif 380 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive); 381 int qemu_unlock_fd(int fd, int64_t start, int64_t len); 382 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive); 383 bool qemu_has_ofd_lock(void); 384 385 #if defined(__HAIKU__) && defined(__i386__) 386 #define FMT_pid "%ld" 387 #elif defined(WIN64) 388 #define FMT_pid "%" PRId64 389 #else 390 #define FMT_pid "%d" 391 #endif 392 393 int qemu_create_pidfile(const char *filename); 394 int qemu_get_thread_id(void); 395 396 #ifndef CONFIG_IOVEC 397 struct iovec { 398 void *iov_base; 399 size_t iov_len; 400 }; 401 /* 402 * Use the same value as Linux for now. 403 */ 404 #define IOV_MAX 1024 405 406 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt); 407 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt); 408 #else 409 #include <sys/uio.h> 410 #endif 411 412 #ifdef _WIN32 413 static inline void qemu_timersub(const struct timeval *val1, 414 const struct timeval *val2, 415 struct timeval *res) 416 { 417 res->tv_sec = val1->tv_sec - val2->tv_sec; 418 if (val1->tv_usec < val2->tv_usec) { 419 res->tv_sec--; 420 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000; 421 } else { 422 res->tv_usec = val1->tv_usec - val2->tv_usec; 423 } 424 } 425 #else 426 #define qemu_timersub timersub 427 #endif 428 429 void qemu_set_cloexec(int fd); 430 431 /* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default 432 * instead of QEMU_VERSION, so setting hw_version on MachineClass 433 * is no longer mandatory. 434 * 435 * Do NOT change this string, or it will break compatibility on all 436 * machine classes that don't set hw_version. 437 */ 438 #define QEMU_HW_VERSION "2.5+" 439 440 /* QEMU "hardware version" setting. Used to replace code that exposed 441 * QEMU_VERSION to guests in the past and need to keep compatibility. 442 * Do not use qemu_hw_version() in new code. 443 */ 444 void qemu_set_hw_version(const char *); 445 const char *qemu_hw_version(void); 446 447 void fips_set_state(bool requested); 448 bool fips_get_state(void); 449 450 /* Return a dynamically allocated pathname denoting a file or directory that is 451 * appropriate for storing local state. 452 * 453 * @relative_pathname need not start with a directory separator; one will be 454 * added automatically. 455 * 456 * The caller is responsible for releasing the value returned with g_free() 457 * after use. 458 */ 459 char *qemu_get_local_state_pathname(const char *relative_pathname); 460 461 /* Find program directory, and save it for later usage with 462 * qemu_get_exec_dir(). 463 * Try OS specific API first, if not working, parse from argv0. */ 464 void qemu_init_exec_dir(const char *argv0); 465 466 /* Get the saved exec dir. 467 * Caller needs to release the returned string by g_free() */ 468 char *qemu_get_exec_dir(void); 469 470 /** 471 * qemu_getauxval: 472 * @type: the auxiliary vector key to lookup 473 * 474 * Search the auxiliary vector for @type, returning the value 475 * or 0 if @type is not present. 476 */ 477 unsigned long qemu_getauxval(unsigned long type); 478 479 void qemu_set_tty_echo(int fd, bool echo); 480 481 void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, 482 Error **errp); 483 484 /** 485 * qemu_get_pid_name: 486 * @pid: pid of a process 487 * 488 * For given @pid fetch its name. Caller is responsible for 489 * freeing the string when no longer needed. 490 * Returns allocated string on success, NULL on failure. 491 */ 492 char *qemu_get_pid_name(pid_t pid); 493 494 /** 495 * qemu_fork: 496 * 497 * A version of fork that avoids signal handler race 498 * conditions that can lead to child process getting 499 * signals that are otherwise only expected by the 500 * parent. It also resets all signal handlers to the 501 * default settings. 502 * 503 * Returns 0 to child process, pid number to parent 504 * or -1 on failure. 505 */ 506 pid_t qemu_fork(Error **errp); 507 508 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even 509 * when intptr_t is 32-bit and we are aligning a long long. 510 */ 511 extern uintptr_t qemu_real_host_page_size; 512 extern intptr_t qemu_real_host_page_mask; 513 514 extern int qemu_icache_linesize; 515 extern int qemu_dcache_linesize; 516 517 #endif 518