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 * For mingw, as of v6.0.0, the function implementing the assert macro is
 127 * not marked as noreturn, so the compiler cannot delete code following an
 128 * assert(false) as unused.  We rely on this within the code base to delete
 129 * code that is unreachable when features are disabled.
 130 * All supported versions of Glib's g_assert() satisfy this requirement.
 131 */
 132#ifdef __MINGW32__
 133#undef assert
 134#define assert(x)  g_assert(x)
 135#endif
 136
 137/*
 138 * According to waitpid man page:
 139 * WCOREDUMP
 140 *  This  macro  is  not  specified  in POSIX.1-2001 and is not
 141 *  available on some UNIX implementations (e.g., AIX, SunOS).
 142 *  Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif.
 143 */
 144#ifndef WCOREDUMP
 145#define WCOREDUMP(status) 0
 146#endif
 147/*
 148 * We have a lot of unaudited code that may fail in strange ways, or
 149 * even be a security risk during migration, if you disable assertions
 150 * at compile-time.  You may comment out these safety checks if you
 151 * absolutely want to disable assertion overhead, but it is not
 152 * supported upstream so the risk is all yours.  Meanwhile, please
 153 * submit patches to remove any side-effects inside an assertion, or
 154 * fixing error handling that should use Error instead of assert.
 155 */
 156#ifdef NDEBUG
 157#error building with NDEBUG is not supported
 158#endif
 159#ifdef G_DISABLE_ASSERT
 160#error building with G_DISABLE_ASSERT is not supported
 161#endif
 162
 163#ifndef O_LARGEFILE
 164#define O_LARGEFILE 0
 165#endif
 166#ifndef O_BINARY
 167#define O_BINARY 0
 168#endif
 169#ifndef MAP_ANONYMOUS
 170#define MAP_ANONYMOUS MAP_ANON
 171#endif
 172#ifndef ENOMEDIUM
 173#define ENOMEDIUM ENODEV
 174#endif
 175#if !defined(ENOTSUP)
 176#define ENOTSUP 4096
 177#endif
 178#if !defined(ECANCELED)
 179#define ECANCELED 4097
 180#endif
 181#if !defined(EMEDIUMTYPE)
 182#define EMEDIUMTYPE 4098
 183#endif
 184#if !defined(ESHUTDOWN)
 185#define ESHUTDOWN 4099
 186#endif
 187
 188/* time_t may be either 32 or 64 bits depending on the host OS, and
 189 * can be either signed or unsigned, so we can't just hardcode a
 190 * specific maximum value. This is not a C preprocessor constant,
 191 * so you can't use TIME_MAX in an #ifdef, but for our purposes
 192 * this isn't a problem.
 193 */
 194
 195/* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from
 196 * Gnulib, and are under the LGPL v2.1 or (at your option) any
 197 * later version.
 198 */
 199
 200/* True if the real type T is signed.  */
 201#define TYPE_SIGNED(t) (!((t)0 < (t)-1))
 202
 203/* The width in bits of the integer type or expression T.
 204 * Padding bits are not supported.
 205 */
 206#define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT)
 207
 208/* The maximum and minimum values for the integer type T.  */
 209#define TYPE_MAXIMUM(t)                                                \
 210  ((t) (!TYPE_SIGNED(t)                                                \
 211        ? (t)-1                                                        \
 212        : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1)))
 213
 214#ifndef TIME_MAX
 215#define TIME_MAX TYPE_MAXIMUM(time_t)
 216#endif
 217
 218/* HOST_LONG_BITS is the size of a native pointer in bits. */
 219#if UINTPTR_MAX == UINT32_MAX
 220# define HOST_LONG_BITS 32
 221#elif UINTPTR_MAX == UINT64_MAX
 222# define HOST_LONG_BITS 64
 223#else
 224# error Unknown pointer size
 225#endif
 226
 227/* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with
 228 * the wrong type. Our replacement isn't usable in preprocessor
 229 * expressions, but it is sufficient for our needs. */
 230#if defined(HAVE_BROKEN_SIZE_MAX) && HAVE_BROKEN_SIZE_MAX
 231#undef SIZE_MAX
 232#define SIZE_MAX ((size_t)-1)
 233#endif
 234
 235#ifndef MIN
 236#define MIN(a, b) (((a) < (b)) ? (a) : (b))
 237#endif
 238#ifndef MAX
 239#define MAX(a, b) (((a) > (b)) ? (a) : (b))
 240#endif
 241
 242/* Minimum function that returns zero only iff both values are zero.
 243 * Intended for use with unsigned values only. */
 244#ifndef MIN_NON_ZERO
 245#define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \
 246                                ((b) == 0 ? (a) : (MIN(a, b))))
 247#endif
 248
 249/* Round number down to multiple */
 250#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
 251
 252/* Round number up to multiple. Safe when m is not a power of 2 (see
 253 * ROUND_UP for a faster version when a power of 2 is guaranteed) */
 254#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
 255
 256/* Check if n is a multiple of m */
 257#define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
 258
 259/* n-byte align pointer down */
 260#define QEMU_ALIGN_PTR_DOWN(p, n) \
 261    ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
 262
 263/* n-byte align pointer up */
 264#define QEMU_ALIGN_PTR_UP(p, n) \
 265    ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
 266
 267/* Check if pointer p is n-bytes aligned */
 268#define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
 269
 270/* Round number up to multiple. Requires that d be a power of 2 (see
 271 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
 272 * numbers); works even if d is a smaller type than n.  */
 273#ifndef ROUND_UP
 274#define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d)))
 275#endif
 276
 277#ifndef DIV_ROUND_UP
 278#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
 279#endif
 280
 281/*
 282 * &(x)[0] is always a pointer - if it's same type as x then the argument is a
 283 * pointer, not an array.
 284 */
 285#define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \
 286                                                        typeof(&(x)[0])))
 287#ifndef ARRAY_SIZE
 288#define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \
 289                       QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x)))
 290#endif
 291
 292int qemu_daemon(int nochdir, int noclose);
 293void *qemu_try_memalign(size_t alignment, size_t size);
 294void *qemu_memalign(size_t alignment, size_t size);
 295void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared);
 296void qemu_vfree(void *ptr);
 297void qemu_anon_ram_free(void *ptr, size_t size);
 298
 299#define QEMU_MADV_INVALID -1
 300
 301#if defined(CONFIG_MADVISE)
 302
 303#define QEMU_MADV_WILLNEED  MADV_WILLNEED
 304#define QEMU_MADV_DONTNEED  MADV_DONTNEED
 305#ifdef MADV_DONTFORK
 306#define QEMU_MADV_DONTFORK  MADV_DONTFORK
 307#else
 308#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 309#endif
 310#ifdef MADV_MERGEABLE
 311#define QEMU_MADV_MERGEABLE MADV_MERGEABLE
 312#else
 313#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 314#endif
 315#ifdef MADV_UNMERGEABLE
 316#define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
 317#else
 318#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 319#endif
 320#ifdef MADV_DODUMP
 321#define QEMU_MADV_DODUMP MADV_DODUMP
 322#else
 323#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 324#endif
 325#ifdef MADV_DONTDUMP
 326#define QEMU_MADV_DONTDUMP MADV_DONTDUMP
 327#else
 328#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 329#endif
 330#ifdef MADV_HUGEPAGE
 331#define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
 332#else
 333#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
 334#endif
 335#ifdef MADV_NOHUGEPAGE
 336#define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
 337#else
 338#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
 339#endif
 340#ifdef MADV_REMOVE
 341#define QEMU_MADV_REMOVE MADV_REMOVE
 342#else
 343#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 344#endif
 345
 346#elif defined(CONFIG_POSIX_MADVISE)
 347
 348#define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
 349#define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
 350#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 351#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 352#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 353#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 354#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 355#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 356#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 357#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 358
 359#else /* no-op */
 360
 361#define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
 362#define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
 363#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 364#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 365#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 366#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 367#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 368#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 369#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 370#define QEMU_MADV_REMOVE QEMU_MADV_INVALID
 371
 372#endif
 373
 374#ifdef _WIN32
 375#define HAVE_CHARDEV_SERIAL 1
 376#elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__)    \
 377    || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
 378    || defined(__GLIBC__)
 379#define HAVE_CHARDEV_SERIAL 1
 380#endif
 381
 382#if defined(__linux__) || defined(__FreeBSD__) ||               \
 383    defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 384#define HAVE_CHARDEV_PARPORT 1
 385#endif
 386
 387#if defined(CONFIG_LINUX)
 388#ifndef BUS_MCEERR_AR
 389#define BUS_MCEERR_AR 4
 390#endif
 391#ifndef BUS_MCEERR_AO
 392#define BUS_MCEERR_AO 5
 393#endif
 394#endif
 395
 396#if defined(__linux__) && \
 397    (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \
 398     || defined(__powerpc64__))
 399   /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
 400      Valgrind does not support alignments larger than 1 MiB,
 401      therefore we need special code which handles running on Valgrind. */
 402#  define QEMU_VMALLOC_ALIGN (512 * 4096)
 403#elif defined(__linux__) && defined(__s390x__)
 404   /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
 405#  define QEMU_VMALLOC_ALIGN (256 * 4096)
 406#elif defined(__linux__) && defined(__sparc__)
 407#include <sys/shm.h>
 408#  define QEMU_VMALLOC_ALIGN MAX(getpagesize(), SHMLBA)
 409#else
 410#  define QEMU_VMALLOC_ALIGN getpagesize()
 411#endif
 412
 413#ifdef CONFIG_POSIX
 414struct qemu_signalfd_siginfo {
 415    uint32_t ssi_signo;   /* Signal number */
 416    int32_t  ssi_errno;   /* Error number (unused) */
 417    int32_t  ssi_code;    /* Signal code */
 418    uint32_t ssi_pid;     /* PID of sender */
 419    uint32_t ssi_uid;     /* Real UID of sender */
 420    int32_t  ssi_fd;      /* File descriptor (SIGIO) */
 421    uint32_t ssi_tid;     /* Kernel timer ID (POSIX timers) */
 422    uint32_t ssi_band;    /* Band event (SIGIO) */
 423    uint32_t ssi_overrun; /* POSIX timer overrun count */
 424    uint32_t ssi_trapno;  /* Trap number that caused signal */
 425    int32_t  ssi_status;  /* Exit status or signal (SIGCHLD) */
 426    int32_t  ssi_int;     /* Integer sent by sigqueue(2) */
 427    uint64_t ssi_ptr;     /* Pointer sent by sigqueue(2) */
 428    uint64_t ssi_utime;   /* User CPU time consumed (SIGCHLD) */
 429    uint64_t ssi_stime;   /* System CPU time consumed (SIGCHLD) */
 430    uint64_t ssi_addr;    /* Address that generated signal
 431                             (for hardware-generated signals) */
 432    uint8_t  pad[48];     /* Pad size to 128 bytes (allow for
 433                             additional fields in the future) */
 434};
 435
 436int qemu_signalfd(const sigset_t *mask);
 437void sigaction_invoke(struct sigaction *action,
 438                      struct qemu_signalfd_siginfo *info);
 439#endif
 440
 441int qemu_madvise(void *addr, size_t len, int advice);
 442int qemu_mprotect_rwx(void *addr, size_t size);
 443int qemu_mprotect_none(void *addr, size_t size);
 444
 445int qemu_open(const char *name, int flags, ...);
 446int qemu_close(int fd);
 447#ifndef _WIN32
 448int qemu_dup(int fd);
 449#endif
 450int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
 451int qemu_unlock_fd(int fd, int64_t start, int64_t len);
 452int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive);
 453bool qemu_has_ofd_lock(void);
 454
 455#if defined(__HAIKU__) && defined(__i386__)
 456#define FMT_pid "%ld"
 457#elif defined(WIN64)
 458#define FMT_pid "%" PRId64
 459#else
 460#define FMT_pid "%d"
 461#endif
 462
 463bool qemu_write_pidfile(const char *pidfile, Error **errp);
 464
 465int qemu_get_thread_id(void);
 466
 467#ifndef CONFIG_IOVEC
 468struct iovec {
 469    void *iov_base;
 470    size_t iov_len;
 471};
 472/*
 473 * Use the same value as Linux for now.
 474 */
 475#define IOV_MAX 1024
 476
 477ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
 478ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
 479#else
 480#include <sys/uio.h>
 481#endif
 482
 483#ifdef _WIN32
 484static inline void qemu_timersub(const struct timeval *val1,
 485                                 const struct timeval *val2,
 486                                 struct timeval *res)
 487{
 488    res->tv_sec = val1->tv_sec - val2->tv_sec;
 489    if (val1->tv_usec < val2->tv_usec) {
 490        res->tv_sec--;
 491        res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
 492    } else {
 493        res->tv_usec = val1->tv_usec - val2->tv_usec;
 494    }
 495}
 496#else
 497#define qemu_timersub timersub
 498#endif
 499
 500void qemu_set_cloexec(int fd);
 501
 502/* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
 503 * instead of QEMU_VERSION, so setting hw_version on MachineClass
 504 * is no longer mandatory.
 505 *
 506 * Do NOT change this string, or it will break compatibility on all
 507 * machine classes that don't set hw_version.
 508 */
 509#define QEMU_HW_VERSION "2.5+"
 510
 511/* QEMU "hardware version" setting. Used to replace code that exposed
 512 * QEMU_VERSION to guests in the past and need to keep compatibility.
 513 * Do not use qemu_hw_version() in new code.
 514 */
 515void qemu_set_hw_version(const char *);
 516const char *qemu_hw_version(void);
 517
 518void fips_set_state(bool requested);
 519bool fips_get_state(void);
 520
 521/* Return a dynamically allocated pathname denoting a file or directory that is
 522 * appropriate for storing local state.
 523 *
 524 * @relative_pathname need not start with a directory separator; one will be
 525 * added automatically.
 526 *
 527 * The caller is responsible for releasing the value returned with g_free()
 528 * after use.
 529 */
 530char *qemu_get_local_state_pathname(const char *relative_pathname);
 531
 532/* Find program directory, and save it for later usage with
 533 * qemu_get_exec_dir().
 534 * Try OS specific API first, if not working, parse from argv0. */
 535void qemu_init_exec_dir(const char *argv0);
 536
 537/* Get the saved exec dir.
 538 * Caller needs to release the returned string by g_free() */
 539char *qemu_get_exec_dir(void);
 540
 541/**
 542 * qemu_getauxval:
 543 * @type: the auxiliary vector key to lookup
 544 *
 545 * Search the auxiliary vector for @type, returning the value
 546 * or 0 if @type is not present.
 547 */
 548unsigned long qemu_getauxval(unsigned long type);
 549
 550void qemu_set_tty_echo(int fd, bool echo);
 551
 552void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus,
 553                     Error **errp);
 554
 555/**
 556 * qemu_get_pid_name:
 557 * @pid: pid of a process
 558 *
 559 * For given @pid fetch its name. Caller is responsible for
 560 * freeing the string when no longer needed.
 561 * Returns allocated string on success, NULL on failure.
 562 */
 563char *qemu_get_pid_name(pid_t pid);
 564
 565/**
 566 * qemu_fork:
 567 *
 568 * A version of fork that avoids signal handler race
 569 * conditions that can lead to child process getting
 570 * signals that are otherwise only expected by the
 571 * parent. It also resets all signal handlers to the
 572 * default settings.
 573 *
 574 * Returns 0 to child process, pid number to parent
 575 * or -1 on failure.
 576 */
 577pid_t qemu_fork(Error **errp);
 578
 579/* Using intptr_t ensures that qemu_*_page_mask is sign-extended even
 580 * when intptr_t is 32-bit and we are aligning a long long.
 581 */
 582extern uintptr_t qemu_real_host_page_size;
 583extern intptr_t qemu_real_host_page_mask;
 584
 585extern int qemu_icache_linesize;
 586extern int qemu_icache_linesize_log;
 587extern int qemu_dcache_linesize;
 588extern int qemu_dcache_linesize_log;
 589
 590#endif
 591