2 * OS includes and handling of OS dependencies
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).
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.
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.
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
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.
30 #include "config-host.h"
32 #include "config-target.h"
34 #include "exec/poison.h"
36 #include "qemu/compiler.h"
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
42 #ifndef __STDC_CONSTANT_MACROS
43 #define __STDC_CONSTANT_MACROS
45 #ifndef __STDC_LIMIT_MACROS
46 #define __STDC_LIMIT_MACROS
48 #ifndef __STDC_FORMAT_MACROS
49 #define __STDC_FORMAT_MACROS
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
56 #define daemon qemu_fake_daemon_function
59 extern int daemon(int, int);
66 #include <sys/types.h>
73 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
74 * function availability on recentish Mingw-w64 platforms. */
83 /* setjmp must be declared before sysemu/os-win32.h
84 * because it is redefined there. */
89 #include <sys/signal.h>
95 #define WIFEXITED(x) 1
96 #define WEXITSTATUS(x) (x)
100 #include "sysemu/os-win32.h"
104 #include "sysemu/os-posix.h"
107 #include "glib-compat.h"
108 #include "qemu/typedefs.h"
111 #define O_LARGEFILE 0
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
120 #define ENOMEDIUM ENODEV
122 #if !defined(ENOTSUP)
125 #if !defined(ECANCELED)
126 #define ECANCELED 4097
128 #if !defined(EMEDIUMTYPE)
129 #define EMEDIUMTYPE 4098
132 #define TIME_MAX LONG_MAX
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
141 # error Unknown pointer size
145 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
148 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
151 /* Minimum function that returns zero only iff both values are zero.
152 * Intended for use with unsigned values only. */
154 #define MIN_NON_ZERO(a, b) (((a) != 0 && (a) < (b)) ? (a) : (b))
157 /* Round number down to multiple */
158 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
160 /* Round number up to multiple */
161 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
163 /* Check if n is a multiple of m */
164 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
166 /* n-byte align pointer down */
167 #define QEMU_ALIGN_PTR_DOWN(p, n) \
168 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
170 /* n-byte align pointer up */
171 #define QEMU_ALIGN_PTR_UP(p, n) \
172 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
174 /* Check if pointer p is n-bytes aligned */
175 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
178 #define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
182 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
186 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
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
);
196 #define QEMU_MADV_INVALID -1
198 #if defined(CONFIG_MADVISE)
200 #include <sys/mman.h>
202 #define QEMU_MADV_WILLNEED MADV_WILLNEED
203 #define QEMU_MADV_DONTNEED MADV_DONTNEED
205 #define QEMU_MADV_DONTFORK MADV_DONTFORK
207 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID
209 #ifdef MADV_MERGEABLE
210 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE
212 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
214 #ifdef MADV_UNMERGEABLE
215 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
217 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
220 #define QEMU_MADV_DODUMP MADV_DODUMP
222 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
225 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP
227 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
230 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
232 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
234 #ifdef MADV_NOHUGEPAGE
235 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
237 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
240 #elif defined(CONFIG_POSIX_MADVISE)
242 #define QEMU_MADV_WILLNEED POSIX_MADV_WILLNEED
243 #define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED
244 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID
245 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
246 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
247 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
248 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
249 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
250 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
254 #define QEMU_MADV_WILLNEED QEMU_MADV_INVALID
255 #define QEMU_MADV_DONTNEED QEMU_MADV_INVALID
256 #define QEMU_MADV_DONTFORK QEMU_MADV_INVALID
257 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
258 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
259 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
260 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
261 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
262 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
266 #if defined(__linux__) && \
267 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))
268 /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
269 Valgrind does not support alignments larger than 1 MiB,
270 therefore we need special code which handles running on Valgrind. */
271 # define QEMU_VMALLOC_ALIGN (512 * 4096)
272 #elif defined(__linux__) && defined(__s390x__)
273 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
274 # define QEMU_VMALLOC_ALIGN (256 * 4096)
276 # define QEMU_VMALLOC_ALIGN getpagesize()
279 int qemu_madvise(void *addr
, size_t len
, int advice
);
281 int qemu_open(const char *name
, int flags
, ...);
282 int qemu_close(int fd
);
284 #if defined(__HAIKU__) && defined(__i386__)
285 #define FMT_pid "%ld"
287 #define FMT_pid "%" PRId64
292 int qemu_create_pidfile(const char *filename
);
293 int qemu_get_thread_id(void);
301 * Use the same value as Linux for now.
305 ssize_t
readv(int fd
, const struct iovec
*iov
, int iov_cnt
);
306 ssize_t
writev(int fd
, const struct iovec
*iov
, int iov_cnt
);
312 static inline void qemu_timersub(const struct timeval
*val1
,
313 const struct timeval
*val2
,
316 res
->tv_sec
= val1
->tv_sec
- val2
->tv_sec
;
317 if (val1
->tv_usec
< val2
->tv_usec
) {
319 res
->tv_usec
= val1
->tv_usec
- val2
->tv_usec
+ 1000 * 1000;
321 res
->tv_usec
= val1
->tv_usec
- val2
->tv_usec
;
325 #define qemu_timersub timersub
328 void qemu_set_cloexec(int fd
);
330 /* Starting on QEMU 2.5, qemu_hw_version() returns "2.5+" by default
331 * instead of QEMU_VERSION, so setting hw_version on MachineClass
332 * is no longer mandatory.
334 * Do NOT change this string, or it will break compatibility on all
335 * machine classes that don't set hw_version.
337 #define QEMU_HW_VERSION "2.5+"
339 /* QEMU "hardware version" setting. Used to replace code that exposed
340 * QEMU_VERSION to guests in the past and need to keep compatibility.
341 * Do not use qemu_hw_version() in new code.
343 void qemu_set_hw_version(const char *);
344 const char *qemu_hw_version(void);
346 void fips_set_state(bool requested
);
347 bool fips_get_state(void);
349 /* Return a dynamically allocated pathname denoting a file or directory that is
350 * appropriate for storing local state.
352 * @relative_pathname need not start with a directory separator; one will be
353 * added automatically.
355 * The caller is responsible for releasing the value returned with g_free()
358 char *qemu_get_local_state_pathname(const char *relative_pathname
);
360 /* Find program directory, and save it for later usage with
361 * qemu_get_exec_dir().
362 * Try OS specific API first, if not working, parse from argv0. */
363 void qemu_init_exec_dir(const char *argv0
);
365 /* Get the saved exec dir.
366 * Caller needs to release the returned string by g_free() */
367 char *qemu_get_exec_dir(void);
371 * @type: the auxiliary vector key to lookup
373 * Search the auxiliary vector for @type, returning the value
374 * or 0 if @type is not present.
376 unsigned long qemu_getauxval(unsigned long type
);
378 void qemu_set_tty_echo(int fd
, bool echo
);
380 void os_mem_prealloc(int fd
, char *area
, size_t sz
);
382 int qemu_read_password(char *buf
, int buf_size
);
387 * A version of fork that avoids signal handler race
388 * conditions that can lead to child process getting
389 * signals that are otherwise only expected by the
390 * parent. It also resets all signal handlers to the
393 * Returns 0 to child process, pid number to parent
396 pid_t
qemu_fork(Error
**errp
);