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#ifdef __COVERITY__
  37/* Coverity does not like the new _Float* types that are used by
  38 * recent glibc, and croaks on every single file that includes
  39 * stdlib.h.  These typedefs are enough to please it.
  40 *
  41 * Note that these fix parse errors so they cannot be placed in
  42 * scripts/coverity-model.c.
  43 */
  44typedef float _Float32;
  45typedef double _Float32x;
  46typedef double _Float64;
  47typedef __float80 _Float64x;
  48typedef __float128 _Float128;
  49#endif
  50
  51#include "qemu/compiler.h"
  52
  53/* Older versions of C++ don't get definitions of various macros from
  54 * stdlib.h unless we define these macros before first inclusion of
  55 * that system header.
  56 */
  57#ifndef __STDC_CONSTANT_MACROS
  58#define __STDC_CONSTANT_MACROS
  59#endif
  60#ifndef __STDC_LIMIT_MACROS
  61#define __STDC_LIMIT_MACROS
  62#endif
  63#ifndef __STDC_FORMAT_MACROS
  64#define __STDC_FORMAT_MACROS
  65#endif
  66
  67/* The following block of code temporarily renames the daemon() function so the
  68 * compiler does not see the warning associated with it in stdlib.h on OSX
  69 */
  70#ifdef __APPLE__
  71#define daemon qemu_fake_daemon_function
  72#include <stdlib.h>
  73#undef daemon
  74extern int daemon(int, int);
  75#endif
  76
  77#include <stdarg.h>
  78#include <stddef.h>
  79#include <stdbool.h>
  80#include <stdint.h>
  81#include <sys/types.h>
  82#include <stdlib.h>
  83#include <stdio.h>
  84#include <string.h>
  85#include <strings.h>
  86#include <inttypes.h>
  87#include <limits.h>
  88/* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
  89 * function availability on recentish Mingw-w64 platforms. */
  90#include <unistd.h>
  91#include <time.h>
  92#include <ctype.h>
  93#include <errno.h>
  94#include <fcntl.h>
  95#include <sys/stat.h>
  96#include <sys/time.h>
  97#include <assert.h>
  98/* setjmp must be declared before sysemu/os-win32.h
  99 * because it is redefined there. */
 100#include <setjmp.h>
 101#include <signal.h>
 102
 103#ifdef __OpenBSD__
 104#include <sys/signal.h>
 105#endif
 106
 107#ifndef _WIN32
 108#include <sys/wait.h>
 109#else
 110#define WIFEXITED(x)   1
 111#define WEXITSTATUS(x) (x)
 112#endif
 113
 114#ifdef _WIN32
 115#include "sysemu/os-win32.h"
 116#endif
 117
 118#ifdef CONFIG_POSIX
 119#include "sysemu/os-posix.h"
 120#endif
 121
 122#include "glib-compat.h"
 123#include "qemu/typedefs.h"
 124
 125/*
 126 * According to waitpid man page:
 127 * WCOREDUMP
 128 *  This  macro  is  not  specified  in POSIX.1-2001 and is not
 129 *  available on some UNIX implementations (e.g., AIX, SunOS).
 130 *  Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif.
 131 */
 132#ifndef WCOREDUMP
 133#define WCOREDUMP(status) 0
 134#endif
 135/*
 136 * We have a lot of unaudited code that may fail in strange ways, or
 137 * even be a security risk during migration, if you disable assertions
 138 * at compile-time.  You may comment out these safety checks if you
 139 * absolutely want to disable assertion overhead, but it is not
 140 * supported upstream so the risk is all yours.  Meanwhile, please
 141 * submit patches to remove any side-effects inside an assertion, or
 142 * fixing error handling that should use Error instead of assert.
 143 */
 144#ifdef NDEBUG
 145#error building with NDEBUG is not supported
 146#endif
 147#ifdef G_DISABLE_ASSERT
 148#error building with G_DISABLE_ASSERT is not supported
 149#endif
 150
 151#ifndef O_LARGEFILE
 152#define O_LARGEFILE 0
 153#endif
 154#ifndef O_BINARY
 155#define O_BINARY 0
 156#endif
 157#ifndef MAP_ANONYMOUS
 158#define MAP_ANONYMOUS MAP_ANON
 159#endif
 160#ifndef ENOMEDIUM
 161#define ENOMEDIUM ENODEV
 162#endif
 163#if !defined(ENOTSUP)
 164#define ENOTSUP 4096
 165#endif
 166#if !defined(ECANCELED)
 167#define ECANCELED 4097
 168#endif
 169#if !defined(EMEDIUMTYPE)
 170#define EMEDIUMTYPE 4098
 171#endif
 172#if !defined(ESHUTDOWN)
 173#define ESHUTDOWN 4099
 174#endif
 175
 176/* time_t may be either 32 or 64 bits depending on the host OS, and
 177 * can be either signed or unsigned, so we can't just hardcode a
 178 * specific maximum value. This is not a C preprocessor constant,
 179 * so you can't use TIME_MAX in an #ifdef, but for our purposes
 180 * this isn't a problem.
 181 */
 182
 183/* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from
 184 * Gnulib, and are under the LGPL v2.1 or (at your option) any
 185 * later version.
 186 */
 187
 188/* True if the real type T is signed.  */
 189#define TYPE_SIGNED(t) (!((t)0 < (t)-1))
 190
 191/* The width in bits of the integer type or expression T.
 192 * Padding bits are not supported.
 193 */
 194#define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT)
 195
 196/* The maximum and minimum values for the integer type T.  */
 197#define TYPE_MAXIMUM(t)                                                \
 198  ((t) (!TYPE_SIGNED(t)                                                \
 199        ? (t)-1                                                        \
 200        : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1)))
 201
 202#ifndef TIME_MAX
 203#define TIME_MAX TYPE_MAXIMUM(time_t)
 204#endif
 205
 206/* HOST_LONG_BITS is the size of a native pointer in bits. */
 207#if UINTPTR_MAX == UINT32_MAX
 208# define HOST_LONG_BITS 32
 209#elif UINTPTR_MAX == UINT64_MAX
 210# define HOST_LONG_BITS 64
 211#else
 212# error Unknown pointer size
 213#endif
 214
 215/* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with
 216 * the wrong type. Our replacement isn't usable in preprocessor
 217 * expressions, but it is sufficient for our needs. */
 218#if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX
 219#undef SIZE_MAX
 220#define SIZE_MAX ((size_t)-1)
 221#endif
 222
 223#ifndef MIN
 224#define MIN(a, b) (((a) < (b)) ? (a) : (b))
 225#endif
 226#ifndef MAX
 227#define MAX(a, b) (((a) > (b)) ? (a) : (b))
 228#endif
 229
 230/* Minimum function that returns zero only iff both values are zero.
 231 * Intended for use with unsigned values only. */
 232#ifndef MIN_NON_ZERO
 233#define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \
 234                                ((b) == 0 ? (a) : (MIN(a, b))))
 235#endif
 236
 237/* Round number down to multiple */
 238#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
 239
 240/* Round number up to multiple. Safe when m is not a power of 2 (see
 241 * ROUND_UP for a faster version when a power of 2 is guaranteed) */
 242#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
 243
 244/* Check if n is a multiple of m */
 245#define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
 246
 247/* n-byte align pointer down */
 248#define QEMU_ALIGN_PTR_DOWN(p, n) \
 249    ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
 250
 251/* n-byte align pointer up */
 252#define QEMU_ALIGN_PTR_UP(p, n) \
 253    ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
 254
 255/* Check if pointer p is n-bytes aligned */
 256#define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
 257
 258/* Round number up to multiple. Requires that d be a power of 2 (see
 259 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
 260 * numbers); works even if d is a smaller type than n.  */
 261#ifndef ROUND_UP
 262#define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d)))
 263#endif
 264
 265#ifndef DIV_ROUND_UP
 266#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
 267#endif
 268
 269/*
 270 * &(x)[0] is always a pointer - if it's same type as x then the argument is a
 271 * pointer, not an array.
 272 */
 273#define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \
 274                                                        typeof(&(x)[0])))
 275#ifndef ARRAY_SIZE
 276#define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \
 277                       QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x)))
 278#endif
 279
 280int qemu_daemon(int nochdir, int noclose);
 281void *qemu_try_memalign(size_t alignment, size_t size);
 282void *qemu_memalign(size_t alignment, size_t size);
 283void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared);
 284void qemu_vfree(void *ptr);
 285void qemu_anon_ram_free(void *ptr, size_t size);
 286
 287#define QEMU_MADV_INVALID -1
 288
 289#if defined(CONFIG_MADVISE)
 290
 291#define QEMU_MADV_WILLNEED  MADV_WILLNEED
 292#define QEMU_MADV_DONTNEED  MADV_DONTNEED
 293#ifdef MADV_DONTFORK
 294#define QEMU_MADV_DONTFORK  MADV_DONTFORK
 295#else
 296#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 297#endif
 298#ifdef MADV_MERGEABLE
 299#define QEMU_MADV_MERGEABLE MADV_MERGEABLE
 300#else
 301#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 302#endif
 303#ifdef MADV_UNMERGEABLE
 304#define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
 305#else
 306#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 307#endif
 308#ifdef MADV_DODUMP
 309#define QEMU_MADV_DODUMP MADV_DODUMP
 310#else
 311#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 312#endif
 313#ifdef MADV_DONTDUMP
 314#define QEMU_MADV_DONTDUMP MADV_DONTDUMP
 315#else
 316#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 317#endif
 318#ifdef MADV_HUGEPAGE
 319#define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
 320#else
 321#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
 322#endif
 323#ifdef MADV_NOHUGEPAGE
 324#define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
 325#else
 326#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
 327#endif
 328#ifdef MADV_REMOVE
 329#define QEMU_MADV_REMOVE MADV_REMOVE
 330#else
 331#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 332#endif
 333
 334#elif defined(CONFIG_POSIX_MADVISE)
 335
 336#define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
 337#define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
 338#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 339#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 340#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 341#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 342#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 343#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 344#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 345#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 346
 347#else /* no-op */
 348
 349#define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
 350#define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
 351#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 352#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 353#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 354#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 355#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 356#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 357#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 358#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 359
 360#endif
 361
 362#ifdef _WIN32
 363#define HAVE_CHARDEV_SERIAL 1
 364#elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__)    \
 365    || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
 366    || defined(__GLIBC__)
 367#define HAVE_CHARDEV_SERIAL 1
 368#endif
 369
 370#if defined(__linux__) || defined(__FreeBSD__) ||               \
 371    defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 372#define HAVE_CHARDEV_PARPORT 1
 373#endif
 374
 375#if defined(CONFIG_LINUX)
 376#ifndef BUS_MCEERR_AR
 377#define BUS_MCEERR_AR 4
 378#endif
 379#ifndef BUS_MCEERR_AO
 380#define BUS_MCEERR_AO 5
 381#endif
 382#endif
 383
 384#if defined(__linux__) && \
 385    (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \
 386     || defined(__powerpc64__))
 387   /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
 388      Valgrind does not support alignments larger than 1 MiB,
 389      therefore we need special code which handles running on Valgrind. */
 390#  define QEMU_VMALLOC_ALIGN (512 * 4096)
 391#elif defined(__linux__) && defined(__s390x__)
 392   /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
 393#  define QEMU_VMALLOC_ALIGN (256 * 4096)
 394#elif defined(__linux__) && defined(__sparc__)
 395#include <sys/shm.h>
 396#  define QEMU_VMALLOC_ALIGN MAX(getpagesize(), SHMLBA)
 397#else
 398#  define QEMU_VMALLOC_ALIGN getpagesize()
 399#endif
 400
 401#ifdef CONFIG_POSIX
 402struct qemu_signalfd_siginfo {
 403    uint32_t ssi_signo;   /* Signal number */
 404    int32_t  ssi_errno;   /* Error number (unused) */
 405    int32_t  ssi_code;    /* Signal code */
 406    uint32_t ssi_pid;     /* PID of sender */
 407    uint32_t ssi_uid;     /* Real UID of sender */
 408    int32_t  ssi_fd;      /* File descriptor (SIGIO) */
 409    uint32_t ssi_tid;     /* Kernel timer ID (POSIX timers) */
 410    uint32_t ssi_band;    /* Band event (SIGIO) */
 411    uint32_t ssi_overrun; /* POSIX timer overrun count */
 412    uint32_t ssi_trapno;  /* Trap number that caused signal */
 413    int32_t  ssi_status;  /* Exit status or signal (SIGCHLD) */
 414    int32_t  ssi_int;     /* Integer sent by sigqueue(2) */
 415    uint64_t ssi_ptr;     /* Pointer sent by sigqueue(2) */
 416    uint64_t ssi_utime;   /* User CPU time consumed (SIGCHLD) */
 417    uint64_t ssi_stime;   /* System CPU time consumed (SIGCHLD) */
 418    uint64_t ssi_addr;    /* Address that generated signal
 419                             (for hardware-generated signals) */
 420    uint8_t  pad[48];     /* Pad size to 128 bytes (allow for
 421                             additional fields in the future) */
 422};
 423
 424int qemu_signalfd(const sigset_t *mask);
 425void sigaction_invoke(struct sigaction *action,
 426                      struct qemu_signalfd_siginfo *info);
 427#endif
 428
 429int qemu_madvise(void *addr, size_t len, int advice);
 430int qemu_mprotect_rwx(void *addr, size_t size);
 431int qemu_mprotect_none(void *addr, size_t size);
 432
 433int qemu_open(const char *name, int flags, ...);
 434int qemu_close(int fd);
 435#ifndef _WIN32
 436int qemu_dup(int fd);
 437#endif
 438int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
 439int qemu_unlock_fd(int fd, int64_t start, int64_t len);
 440int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive);
 441bool qemu_has_ofd_lock(void);
 442
 443#if defined(__HAIKU__) && defined(__i386__)
 444#define FMT_pid "%ld"
 445#elif defined(WIN64)
 446#define FMT_pid "%" PRId64
 447#else
 448#define FMT_pid "%d"
 449#endif
 450
 451int qemu_create_pidfile(const char *filename);
 452int qemu_get_thread_id(void);
 453
 454#ifndef CONFIG_IOVEC
 455struct iovec {
 456    void *iov_base;
 457    size_t iov_len;
 458};
 459/*
 460 * Use the same value as Linux for now.
 461 */
 462#define IOV_MAX 1024
 463
 464ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
 465ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
 466#else
 467#include <sys/uio.h>
 468#endif
 469
 470#ifdef _WIN32
 471static inline void qemu_timersub(const struct timeval *val1,
 472                                 const struct timeval *val2,
 473                                 struct timeval *res)
 474{
 475    res->tv_sec = val1->tv_sec - val2->tv_sec;
 476    if (val1->tv_usec < val2->tv_usec) {
 477        res->tv_sec--;
 478        res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
 479    } else {
 480        res->tv_usec = val1->tv_usec - val2->tv_usec;
 481    }
 482}
 483#else
 484#define qemu_timersub timersub
 485#endif
 486
 487void qemu_set_cloexec(int fd);
 488
 489/* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
 490 * instead of QEMU_VERSION, so setting hw_version on MachineClass
 491 * is no longer mandatory.
 492 *
 493 * Do NOT change this string, or it will break compatibility on all
 494 * machine classes that don't set hw_version.
 495 */
 496#define QEMU_HW_VERSION "2.5+"
 497
 498/* QEMU "hardware version" setting. Used to replace code that exposed
 499 * QEMU_VERSION to guests in the past and need to keep compatibility.
 500 * Do not use qemu_hw_version() in new code.
 501 */
 502void qemu_set_hw_version(const char *);
 503const char *qemu_hw_version(void);
 504
 505void fips_set_state(bool requested);
 506bool fips_get_state(void);
 507
 508/* Return a dynamically allocated pathname denoting a file or directory that is
 509 * appropriate for storing local state.
 510 *
 511 * @relative_pathname need not start with a directory separator; one will be
 512 * added automatically.
 513 *
 514 * The caller is responsible for releasing the value returned with g_free()
 515 * after use.
 516 */
 517char *qemu_get_local_state_pathname(const char *relative_pathname);
 518
 519/* Find program directory, and save it for later usage with
 520 * qemu_get_exec_dir().
 521 * Try OS specific API first, if not working, parse from argv0. */
 522void qemu_init_exec_dir(const char *argv0);
 523
 524/* Get the saved exec dir.
 525 * Caller needs to release the returned string by g_free() */
 526char *qemu_get_exec_dir(void);
 527
 528/**
 529 * qemu_getauxval:
 530 * @type: the auxiliary vector key to lookup
 531 *
 532 * Search the auxiliary vector for @type, returning the value
 533 * or 0 if @type is not present.
 534 */
 535unsigned long qemu_getauxval(unsigned long type);
 536
 537void qemu_set_tty_echo(int fd, bool echo);
 538
 539void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus,
 540                     Error **errp);
 541
 542/**
 543 * qemu_get_pid_name:
 544 * @pid: pid of a process
 545 *
 546 * For given @pid fetch its name. Caller is responsible for
 547 * freeing the string when no longer needed.
 548 * Returns allocated string on success, NULL on failure.
 549 */
 550char *qemu_get_pid_name(pid_t pid);
 551
 552/**
 553 * qemu_fork:
 554 *
 555 * A version of fork that avoids signal handler race
 556 * conditions that can lead to child process getting
 557 * signals that are otherwise only expected by the
 558 * parent. It also resets all signal handlers to the
 559 * default settings.
 560 *
 561 * Returns 0 to child process, pid number to parent
 562 * or -1 on failure.
 563 */
 564pid_t qemu_fork(Error **errp);
 565
 566/* Using intptr_t ensures that qemu_*_page_mask is sign-extended even
 567 * when intptr_t is 32-bit and we are aligning a long long.
 568 */
 569extern uintptr_t qemu_real_host_page_size;
 570extern intptr_t qemu_real_host_page_mask;
 571
 572extern int qemu_icache_linesize;
 573extern int qemu_dcache_linesize;
 574
 575#endif
 576