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