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#ifndef O_LARGEFILE
 111#define O_LARGEFILE 0
 112#endif
 113#ifndef O_BINARY
 114#define O_BINARY 0
 115#endif
 116#ifndef MAP_ANONYMOUS
 117#define MAP_ANONYMOUS MAP_ANON
 118#endif
 119#ifndef ENOMEDIUM
 120#define ENOMEDIUM ENODEV
 121#endif
 122#if !defined(ENOTSUP)
 123#define ENOTSUP 4096
 124#endif
 125#if !defined(ECANCELED)
 126#define ECANCELED 4097
 127#endif
 128#if !defined(EMEDIUMTYPE)
 129#define EMEDIUMTYPE 4098
 130#endif
 131#ifndef TIME_MAX
 132#define TIME_MAX LONG_MAX
 133#endif
 134
 135/* HOST_LONG_BITS is the size of a native pointer in bits. */
 136#if UINTPTR_MAX == UINT32_MAX
 137# define HOST_LONG_BITS 32
 138#elif UINTPTR_MAX == UINT64_MAX
 139# define HOST_LONG_BITS 64
 140#else
 141# error Unknown pointer size
 142#endif
 143
 144#ifndef MIN
 145#define MIN(a, b) (((a) < (b)) ? (a) : (b))
 146#endif
 147#ifndef MAX
 148#define MAX(a, b) (((a) > (b)) ? (a) : (b))
 149#endif
 150
 151/* Minimum function that returns zero only iff both values are zero.
 152 * Intended for use with unsigned values only. */
 153#ifndef MIN_NON_ZERO
 154#define MIN_NON_ZERO(a, b) ((a) == 0 ? (b) : \
 155                                ((b) == 0 ? (a) : (MIN(a, b))))
 156#endif
 157
 158/* Round number down to multiple */
 159#define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
 160
 161/* Round number up to multiple. Safe when m is not a power of 2 (see
 162 * ROUND_UP for a faster version when a power of 2 is guaranteed) */
 163#define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
 164
 165/* Check if n is a multiple of m */
 166#define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
 167
 168/* n-byte align pointer down */
 169#define QEMU_ALIGN_PTR_DOWN(p, n) \
 170    ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
 171
 172/* n-byte align pointer up */
 173#define QEMU_ALIGN_PTR_UP(p, n) \
 174    ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
 175
 176/* Check if pointer p is n-bytes aligned */
 177#define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
 178
 179/* Round number up to multiple. Requires that d be a power of 2 (see
 180 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
 181 * numbers) */
 182#ifndef ROUND_UP
 183#define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
 184#endif
 185
 186#ifndef DIV_ROUND_UP
 187#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 188#endif
 189
 190#ifndef ARRAY_SIZE
 191#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 192#endif
 193
 194int qemu_daemon(int nochdir, int noclose);
 195void *qemu_try_memalign(size_t alignment, size_t size);
 196void *qemu_memalign(size_t alignment, size_t size);
 197void *qemu_anon_ram_alloc(size_t size, uint64_t *align);
 198void qemu_vfree(void *ptr);
 199void qemu_anon_ram_free(void *ptr, size_t size);
 200
 201#define QEMU_MADV_INVALID -1
 202
 203#if defined(CONFIG_MADVISE)
 204
 205#define QEMU_MADV_WILLNEED  MADV_WILLNEED
 206#define QEMU_MADV_DONTNEED  MADV_DONTNEED
 207#ifdef MADV_DONTFORK
 208#define QEMU_MADV_DONTFORK  MADV_DONTFORK
 209#else
 210#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 211#endif
 212#ifdef MADV_MERGEABLE
 213#define QEMU_MADV_MERGEABLE MADV_MERGEABLE
 214#else
 215#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 216#endif
 217#ifdef MADV_UNMERGEABLE
 218#define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
 219#else
 220#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 221#endif
 222#ifdef MADV_DODUMP
 223#define QEMU_MADV_DODUMP MADV_DODUMP
 224#else
 225#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 226#endif
 227#ifdef MADV_DONTDUMP
 228#define QEMU_MADV_DONTDUMP MADV_DONTDUMP
 229#else
 230#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 231#endif
 232#ifdef MADV_HUGEPAGE
 233#define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
 234#else
 235#define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
 236#endif
 237#ifdef MADV_NOHUGEPAGE
 238#define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
 239#else
 240#define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
 241#endif
 242
 243#elif defined(CONFIG_POSIX_MADVISE)
 244
 245#define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
 246#define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
 247#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 248#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 249#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 250#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 251#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 252#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 253#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 254
 255#else /* no-op */
 256
 257#define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
 258#define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
 259#define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
 260#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
 261#define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
 262#define QEMU_MADV_DODUMP QEMU_MADV_INVALID
 263#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
 264#define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
 265#define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
 266
 267#endif
 268
 269#if defined(__linux__) && \
 270    (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))
 271   /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
 272      Valgrind does not support alignments larger than 1 MiB,
 273      therefore we need special code which handles running on Valgrind. */
 274#  define QEMU_VMALLOC_ALIGN (512 * 4096)
 275#elif defined(__linux__) && defined(__s390x__)
 276   /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
 277#  define QEMU_VMALLOC_ALIGN (256 * 4096)
 278#else
 279#  define QEMU_VMALLOC_ALIGN getpagesize()
 280#endif
 281
 282int qemu_madvise(void *addr, size_t len, int advice);
 283
 284int qemu_open(const char *name, int flags, ...);
 285int qemu_close(int fd);
 286#ifndef _WIN32
 287int qemu_dup(int fd);
 288#endif
 289
 290#if defined(__HAIKU__) && defined(__i386__)
 291#define FMT_pid "%ld"
 292#elif defined(WIN64)
 293#define FMT_pid "%" PRId64
 294#else
 295#define FMT_pid "%d"
 296#endif
 297
 298int qemu_create_pidfile(const char *filename);
 299int qemu_get_thread_id(void);
 300
 301#ifndef CONFIG_IOVEC
 302struct iovec {
 303    void *iov_base;
 304    size_t iov_len;
 305};
 306/*
 307 * Use the same value as Linux for now.
 308 */
 309#define IOV_MAX 1024
 310
 311ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
 312ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
 313#else
 314#include <sys/uio.h>
 315#endif
 316
 317#ifdef _WIN32
 318static inline void qemu_timersub(const struct timeval *val1,
 319                                 const struct timeval *val2,
 320                                 struct timeval *res)
 321{
 322    res->tv_sec = val1->tv_sec - val2->tv_sec;
 323    if (val1->tv_usec < val2->tv_usec) {
 324        res->tv_sec--;
 325        res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
 326    } else {
 327        res->tv_usec = val1->tv_usec - val2->tv_usec;
 328    }
 329}
 330#else
 331#define qemu_timersub timersub
 332#endif
 333
 334void qemu_set_cloexec(int fd);
 335
 336/* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
 337 * instead of QEMU_VERSION, so setting hw_version on MachineClass
 338 * is no longer mandatory.
 339 *
 340 * Do NOT change this string, or it will break compatibility on all
 341 * machine classes that don't set hw_version.
 342 */
 343#define QEMU_HW_VERSION "2.5+"
 344
 345/* QEMU "hardware version" setting. Used to replace code that exposed
 346 * QEMU_VERSION to guests in the past and need to keep compatibility.
 347 * Do not use qemu_hw_version() in new code.
 348 */
 349void qemu_set_hw_version(const char *);
 350const char *qemu_hw_version(void);
 351
 352void fips_set_state(bool requested);
 353bool fips_get_state(void);
 354
 355/* Return a dynamically allocated pathname denoting a file or directory that is
 356 * appropriate for storing local state.
 357 *
 358 * @relative_pathname need not start with a directory separator; one will be
 359 * added automatically.
 360 *
 361 * The caller is responsible for releasing the value returned with g_free()
 362 * after use.
 363 */
 364char *qemu_get_local_state_pathname(const char *relative_pathname);
 365
 366/* Find program directory, and save it for later usage with
 367 * qemu_get_exec_dir().
 368 * Try OS specific API first, if not working, parse from argv0. */
 369void qemu_init_exec_dir(const char *argv0);
 370
 371/* Get the saved exec dir.
 372 * Caller needs to release the returned string by g_free() */
 373char *qemu_get_exec_dir(void);
 374
 375/**
 376 * qemu_getauxval:
 377 * @type: the auxiliary vector key to lookup
 378 *
 379 * Search the auxiliary vector for @type, returning the value
 380 * or 0 if @type is not present.
 381 */
 382unsigned long qemu_getauxval(unsigned long type);
 383
 384void qemu_set_tty_echo(int fd, bool echo);
 385
 386void os_mem_prealloc(int fd, char *area, size_t sz, Error **errp);
 387
 388int qemu_read_password(char *buf, int buf_size);
 389
 390/**
 391 * qemu_fork:
 392 *
 393 * A version of fork that avoids signal handler race
 394 * conditions that can lead to child process getting
 395 * signals that are otherwise only expected by the
 396 * parent. It also resets all signal handlers to the
 397 * default settings.
 398 *
 399 * Returns 0 to child process, pid number to parent
 400 * or -1 on failure.
 401 */
 402pid_t qemu_fork(Error **errp);
 403
 404#endif
 405