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CommitLineData
d3b12f5d
PB
1/*
2 * QEMU System Emulator
3 *
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
d3b12f5d 24
0ec024f6 25#include "qemu-common.h"
1de7afc9 26#include "qemu/timer.h"
0ec024f6 27#include "slirp/slirp.h"
1de7afc9 28#include "qemu/main-loop.h"
737e150e 29#include "block/aio.h"
d3b12f5d
PB
30
31#ifndef _WIN32
32
1de7afc9 33#include "qemu/compatfd.h"
0ec024f6 34
d3b12f5d
PB
35/* If we have signalfd, we mask out the signals we want to handle and then
36 * use signalfd to listen for them. We rely on whatever the current signal
37 * handler is to dispatch the signals when we receive them.
38 */
39static void sigfd_handler(void *opaque)
40{
41 int fd = (intptr_t)opaque;
42 struct qemu_signalfd_siginfo info;
43 struct sigaction action;
44 ssize_t len;
45
46 while (1) {
47 do {
48 len = read(fd, &info, sizeof(info));
49 } while (len == -1 && errno == EINTR);
50
51 if (len == -1 && errno == EAGAIN) {
52 break;
53 }
54
55 if (len != sizeof(info)) {
56 printf("read from sigfd returned %zd: %m\n", len);
57 return;
58 }
59
60 sigaction(info.ssi_signo, NULL, &action);
61 if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
62 action.sa_sigaction(info.ssi_signo,
63 (siginfo_t *)&info, NULL);
64 } else if (action.sa_handler) {
65 action.sa_handler(info.ssi_signo);
66 }
67 }
68}
69
70static int qemu_signal_init(void)
71{
72 int sigfd;
73 sigset_t set;
74
75 /*
76 * SIG_IPI must be blocked in the main thread and must not be caught
77 * by sigwait() in the signal thread. Otherwise, the cpu thread will
78 * not catch it reliably.
79 */
80 sigemptyset(&set);
81 sigaddset(&set, SIG_IPI);
d3b12f5d
PB
82 sigaddset(&set, SIGIO);
83 sigaddset(&set, SIGALRM);
84 sigaddset(&set, SIGBUS);
85 pthread_sigmask(SIG_BLOCK, &set, NULL);
86
4aa7534d 87 sigdelset(&set, SIG_IPI);
d3b12f5d
PB
88 sigfd = qemu_signalfd(&set);
89 if (sigfd == -1) {
90 fprintf(stderr, "failed to create signalfd\n");
91 return -errno;
92 }
93
94 fcntl_setfl(sigfd, O_NONBLOCK);
95
96 qemu_set_fd_handler2(sigfd, NULL, sigfd_handler, NULL,
97 (void *)(intptr_t)sigfd);
98
99 return 0;
100}
101
102#else /* _WIN32 */
103
4c8d0d27 104static int qemu_signal_init(void)
d3b12f5d 105{
d3b12f5d
PB
106 return 0;
107}
4c8d0d27
PB
108#endif
109
110static AioContext *qemu_aio_context;
d3b12f5d 111
5f3aa1ff
SH
112AioContext *qemu_get_aio_context(void)
113{
114 return qemu_aio_context;
115}
116
d3b12f5d
PB
117void qemu_notify_event(void)
118{
4c8d0d27 119 if (!qemu_aio_context) {
ee77dfb2
MR
120 return;
121 }
4c8d0d27 122 aio_notify(qemu_aio_context);
d3b12f5d
PB
123}
124
cbff4b34
SH
125static GArray *gpollfds;
126
172061a0 127int qemu_init_main_loop(void)
d3b12f5d
PB
128{
129 int ret;
82cbbdc6 130 GSource *src;
d3b12f5d 131
172061a0 132 init_clocks();
f9ab4654
PB
133 if (init_timer_alarm() < 0) {
134 fprintf(stderr, "could not initialize alarm timer\n");
135 exit(1);
136 }
172061a0 137
d3b12f5d
PB
138 ret = qemu_signal_init();
139 if (ret) {
140 return ret;
141 }
142
cbff4b34 143 gpollfds = g_array_new(FALSE, FALSE, sizeof(GPollFD));
f627aab1 144 qemu_aio_context = aio_context_new();
82cbbdc6
PB
145 src = aio_get_g_source(qemu_aio_context);
146 g_source_attach(src, NULL);
147 g_source_unref(src);
d3b12f5d
PB
148 return 0;
149}
150
d3b12f5d
PB
151static int max_priority;
152
ea26ce76 153#ifndef _WIN32
48ce11ff
SH
154static int glib_pollfds_idx;
155static int glib_n_poll_fds;
156
157static void glib_pollfds_fill(uint32_t *cur_timeout)
d3b12f5d
PB
158{
159 GMainContext *context = g_main_context_default();
4dae83ae 160 int timeout = 0;
48ce11ff 161 int n;
d3b12f5d
PB
162
163 g_main_context_prepare(context, &max_priority);
164
48ce11ff
SH
165 glib_pollfds_idx = gpollfds->len;
166 n = glib_n_poll_fds;
167 do {
168 GPollFD *pfds;
169 glib_n_poll_fds = n;
170 g_array_set_size(gpollfds, glib_pollfds_idx + glib_n_poll_fds);
171 pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
172 n = g_main_context_query(context, max_priority, &timeout, pfds,
173 glib_n_poll_fds);
174 } while (n != glib_n_poll_fds);
d3b12f5d 175
4dae83ae
PB
176 if (timeout >= 0 && timeout < *cur_timeout) {
177 *cur_timeout = timeout;
d3b12f5d
PB
178 }
179}
180
48ce11ff 181static void glib_pollfds_poll(void)
d3b12f5d
PB
182{
183 GMainContext *context = g_main_context_default();
48ce11ff 184 GPollFD *pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
d3b12f5d 185
48ce11ff 186 if (g_main_context_check(context, max_priority, pfds, glib_n_poll_fds)) {
d3b12f5d
PB
187 g_main_context_dispatch(context);
188 }
189}
190
7c7db755 191static int os_host_main_loop_wait(uint32_t timeout)
15455536 192{
15455536
PB
193 int ret;
194
48ce11ff 195 glib_pollfds_fill(&timeout);
15455536
PB
196
197 if (timeout > 0) {
198 qemu_mutex_unlock_iothread();
199 }
200
cbff4b34
SH
201 ret = g_poll((GPollFD *)gpollfds->data, gpollfds->len, timeout);
202
15455536
PB
203 if (timeout > 0) {
204 qemu_mutex_lock_iothread();
205 }
206
48ce11ff 207 glib_pollfds_poll();
15455536
PB
208 return ret;
209}
210#else
d3b12f5d
PB
211/***********************************************************/
212/* Polling handling */
213
214typedef struct PollingEntry {
215 PollingFunc *func;
216 void *opaque;
217 struct PollingEntry *next;
218} PollingEntry;
219
220static PollingEntry *first_polling_entry;
221
222int qemu_add_polling_cb(PollingFunc *func, void *opaque)
223{
224 PollingEntry **ppe, *pe;
225 pe = g_malloc0(sizeof(PollingEntry));
226 pe->func = func;
227 pe->opaque = opaque;
228 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next);
229 *ppe = pe;
230 return 0;
231}
232
233void qemu_del_polling_cb(PollingFunc *func, void *opaque)
234{
235 PollingEntry **ppe, *pe;
236 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) {
237 pe = *ppe;
238 if (pe->func == func && pe->opaque == opaque) {
239 *ppe = pe->next;
240 g_free(pe);
241 break;
242 }
243 }
244}
245
246/***********************************************************/
247/* Wait objects support */
248typedef struct WaitObjects {
249 int num;
06ac7d49 250 int revents[MAXIMUM_WAIT_OBJECTS + 1];
d3b12f5d
PB
251 HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
252 WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
253 void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
254} WaitObjects;
255
256static WaitObjects wait_objects = {0};
257
258int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
259{
260 WaitObjects *w = &wait_objects;
261 if (w->num >= MAXIMUM_WAIT_OBJECTS) {
262 return -1;
263 }
264 w->events[w->num] = handle;
265 w->func[w->num] = func;
266 w->opaque[w->num] = opaque;
06ac7d49 267 w->revents[w->num] = 0;
d3b12f5d
PB
268 w->num++;
269 return 0;
270}
271
272void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
273{
274 int i, found;
275 WaitObjects *w = &wait_objects;
276
277 found = 0;
278 for (i = 0; i < w->num; i++) {
279 if (w->events[i] == handle) {
280 found = 1;
281 }
282 if (found) {
283 w->events[i] = w->events[i + 1];
284 w->func[i] = w->func[i + 1];
285 w->opaque[i] = w->opaque[i + 1];
06ac7d49 286 w->revents[i] = w->revents[i + 1];
d3b12f5d
PB
287 }
288 }
289 if (found) {
290 w->num--;
291 }
292}
293
d3385eb4
PB
294void qemu_fd_register(int fd)
295{
4c8d0d27
PB
296 WSAEventSelect(fd, event_notifier_get_handle(&qemu_aio_context->notifier),
297 FD_READ | FD_ACCEPT | FD_CLOSE |
d3385eb4
PB
298 FD_CONNECT | FD_WRITE | FD_OOB);
299}
300
cbff4b34
SH
301static int pollfds_fill(GArray *pollfds, fd_set *rfds, fd_set *wfds,
302 fd_set *xfds)
303{
304 int nfds = -1;
305 int i;
306
307 for (i = 0; i < pollfds->len; i++) {
308 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
309 int fd = pfd->fd;
310 int events = pfd->events;
311 if (events & (G_IO_IN | G_IO_HUP | G_IO_ERR)) {
312 FD_SET(fd, rfds);
313 nfds = MAX(nfds, fd);
314 }
315 if (events & (G_IO_OUT | G_IO_ERR)) {
316 FD_SET(fd, wfds);
317 nfds = MAX(nfds, fd);
318 }
319 if (events & G_IO_PRI) {
320 FD_SET(fd, xfds);
321 nfds = MAX(nfds, fd);
322 }
323 }
324 return nfds;
325}
326
327static void pollfds_poll(GArray *pollfds, int nfds, fd_set *rfds,
328 fd_set *wfds, fd_set *xfds)
329{
330 int i;
331
332 for (i = 0; i < pollfds->len; i++) {
333 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
334 int fd = pfd->fd;
335 int revents = 0;
336
337 if (FD_ISSET(fd, rfds)) {
338 revents |= G_IO_IN | G_IO_HUP | G_IO_ERR;
339 }
340 if (FD_ISSET(fd, wfds)) {
341 revents |= G_IO_OUT | G_IO_ERR;
342 }
343 if (FD_ISSET(fd, xfds)) {
344 revents |= G_IO_PRI;
345 }
346 pfd->revents = revents & pfd->events;
347 }
348}
349
7c7db755 350static int os_host_main_loop_wait(uint32_t timeout)
d3b12f5d 351{
ea26ce76 352 GMainContext *context = g_main_context_default();
48ce11ff 353 GPollFD poll_fds[1024 * 2]; /* this is probably overkill */
134a03e0 354 int select_ret = 0;
48ce11ff 355 int g_poll_ret, ret, i, n_poll_fds;
d3b12f5d 356 PollingEntry *pe;
d3385eb4 357 WaitObjects *w = &wait_objects;
42fe1c24 358 gint poll_timeout;
15455536 359 static struct timeval tv0;
9cbaacf9
SH
360 fd_set rfds, wfds, xfds;
361 int nfds;
d3b12f5d
PB
362
363 /* XXX: need to suppress polling by better using win32 events */
364 ret = 0;
365 for (pe = first_polling_entry; pe != NULL; pe = pe->next) {
366 ret |= pe->func(pe->opaque);
367 }
d3385eb4
PB
368 if (ret != 0) {
369 return ret;
370 }
d3b12f5d 371
ea26ce76 372 g_main_context_prepare(context, &max_priority);
42fe1c24 373 n_poll_fds = g_main_context_query(context, max_priority, &poll_timeout,
ea26ce76
PB
374 poll_fds, ARRAY_SIZE(poll_fds));
375 g_assert(n_poll_fds <= ARRAY_SIZE(poll_fds));
376
06ac7d49 377 for (i = 0; i < w->num; i++) {
58b9630d 378 poll_fds[n_poll_fds + i].fd = (DWORD_PTR)w->events[i];
ea26ce76 379 poll_fds[n_poll_fds + i].events = G_IO_IN;
06ac7d49
PB
380 }
381
3239ad04
SW
382 if (poll_timeout < 0 || timeout < poll_timeout) {
383 poll_timeout = timeout;
384 }
385
d3385eb4 386 qemu_mutex_unlock_iothread();
5e3bc735 387 g_poll_ret = g_poll(poll_fds, n_poll_fds + w->num, poll_timeout);
d3385eb4 388 qemu_mutex_lock_iothread();
5e3bc735 389 if (g_poll_ret > 0) {
06ac7d49 390 for (i = 0; i < w->num; i++) {
ea26ce76 391 w->revents[i] = poll_fds[n_poll_fds + i].revents;
d3385eb4 392 }
06ac7d49
PB
393 for (i = 0; i < w->num; i++) {
394 if (w->revents[i] && w->func[i]) {
395 w->func[i](w->opaque[i]);
d3b12f5d 396 }
d3b12f5d
PB
397 }
398 }
399
ea26ce76
PB
400 if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) {
401 g_main_context_dispatch(context);
402 }
403
5e3bc735
FC
404 /* Call select after g_poll to avoid a useless iteration and therefore
405 * improve socket latency.
d3385eb4
PB
406 */
407
cbff4b34
SH
408 FD_ZERO(&rfds);
409 FD_ZERO(&wfds);
410 FD_ZERO(&xfds);
411 nfds = pollfds_fill(gpollfds, &rfds, &wfds, &xfds);
5e3bc735
FC
412 if (nfds >= 0) {
413 select_ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv0);
414 if (select_ret != 0) {
415 timeout = 0;
416 }
cbff4b34
SH
417 if (select_ret > 0) {
418 pollfds_poll(gpollfds, nfds, &rfds, &wfds, &xfds);
419 }
5e3bc735
FC
420 }
421
422 return select_ret || g_poll_ret;
d3b12f5d
PB
423}
424#endif
425
426int main_loop_wait(int nonblocking)
427{
7c7db755
SS
428 int ret;
429 uint32_t timeout = UINT32_MAX;
d3b12f5d
PB
430
431 if (nonblocking) {
432 timeout = 0;
d3b12f5d
PB
433 }
434
d3b12f5d 435 /* poll any events */
cbff4b34 436 g_array_set_size(gpollfds, 0); /* reset for new iteration */
d3b12f5d 437 /* XXX: separate device handlers from system ones */
d3b12f5d 438#ifdef CONFIG_SLIRP
7c7db755 439 slirp_update_timeout(&timeout);
8917c3bd 440 slirp_pollfds_fill(gpollfds);
d3b12f5d 441#endif
a3e4b4a8 442 qemu_iohandler_fill(gpollfds);
15455536 443 ret = os_host_main_loop_wait(timeout);
a3e4b4a8 444 qemu_iohandler_poll(gpollfds, ret);
d3b12f5d 445#ifdef CONFIG_SLIRP
8917c3bd 446 slirp_pollfds_poll(gpollfds, (ret < 0));
d3b12f5d
PB
447#endif
448
449 qemu_run_all_timers();
450
d3b12f5d
PB
451 return ret;
452}
f627aab1
PB
453
454/* Functions to operate on the main QEMU AioContext. */
455
456QEMUBH *qemu_bh_new(QEMUBHFunc *cb, void *opaque)
457{
458 return aio_bh_new(qemu_aio_context, cb, opaque);
459}
460
a915f4bc
PB
461bool qemu_aio_wait(void)
462{
7c0628b2 463 return aio_poll(qemu_aio_context, true);
a915f4bc
PB
464}
465
f42b2207 466#ifdef CONFIG_POSIX
a915f4bc
PB
467void qemu_aio_set_fd_handler(int fd,
468 IOHandler *io_read,
469 IOHandler *io_write,
470 AioFlushHandler *io_flush,
471 void *opaque)
472{
473 aio_set_fd_handler(qemu_aio_context, fd, io_read, io_write, io_flush,
474 opaque);
a915f4bc 475}
82cbbdc6 476#endif
a915f4bc 477
a915f4bc
PB
478void qemu_aio_set_event_notifier(EventNotifier *notifier,
479 EventNotifierHandler *io_read,
480 AioFlushEventNotifierHandler *io_flush)
481{
82cbbdc6 482 aio_set_event_notifier(qemu_aio_context, notifier, io_read, io_flush);
a915f4bc 483}