LXR qemu/include/qemu/osdep.h

   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
  59extern 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
 255int qemu_daemon(int nochdir, int noclose);
 256void *qemu_try_memalign(size_t alignment, size_t size);
 257void *qemu_memalign(size_t alignment, size_t size);
 258void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared);
 259void qemu_vfree(void *ptr);
 260void 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
 376struct 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
 398int qemu_signalfd(const sigset_t *mask);
 399void sigaction_invoke(struct sigaction *action,
 400                      struct qemu_signalfd_siginfo *info);
 401#endif
 402
 403int qemu_madvise(void *addr, size_t len, int advice);
 404int qemu_mprotect_rwx(void *addr, size_t size);
 405int qemu_mprotect_none(void *addr, size_t size);
 406
 407int qemu_open(const char *name, int flags, ...);
 408int qemu_close(int fd);
 409#ifndef _WIN32
 410int qemu_dup(int fd);
 411#endif
 412int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
 413int qemu_unlock_fd(int fd, int64_t start, int64_t len);
 414int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive);
 415bool 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
 425int qemu_create_pidfile(const char *filename);
 426int qemu_get_thread_id(void);
 427
 428#ifndef CONFIG_IOVEC
 429struct 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
 438ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
 439ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
 440#else
 441#include <sys/uio.h>
 442#endif
 443
 444#ifdef _WIN32
 445static 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
 461void 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 */
 476void qemu_set_hw_version(const char *);
 477const char *qemu_hw_version(void);
 478
 479void fips_set_state(bool requested);
 480bool 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 */
 491char *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. */
 496void 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() */
 500char *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 */
 509unsigned long qemu_getauxval(unsigned long type);
 510
 511void qemu_set_tty_echo(int fd, bool echo);
 512
 513void 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 */
 524char *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 */
 538pid_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 */
 543extern uintptr_t qemu_real_host_page_size;
 544extern intptr_t qemu_real_host_page_mask;
 545
 546extern int qemu_icache_linesize;
 547extern int qemu_dcache_linesize;
 548
 549#endif
 550