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25#include "qemu/osdep.h"
26#include "qapi/error.h"
27#include "qemu/cutils.h"
28#include "qemu/timer.h"
29#include "sysemu/cpu-timers.h"
30#include "sysemu/replay.h"
31#include "qemu/main-loop.h"
32#include "block/aio.h"
33#include "qemu/error-report.h"
34#include "qemu/queue.h"
35#include "qemu/compiler.h"
36
37#ifndef _WIN32
38#include <sys/wait.h>
39#endif
40
41#ifndef _WIN32
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56QEMU_DISABLE_CFI
57static void sigfd_handler(void *opaque)
58{
59 int fd = (intptr_t)opaque;
60 struct qemu_signalfd_siginfo info;
61 struct sigaction action;
62 ssize_t len;
63
64 while (1) {
65 do {
66 len = read(fd, &info, sizeof(info));
67 } while (len == -1 && errno == EINTR);
68
69 if (len == -1 && errno == EAGAIN) {
70 break;
71 }
72
73 if (len != sizeof(info)) {
74 error_report("read from sigfd returned %zd: %s", len,
75 g_strerror(errno));
76 return;
77 }
78
79 sigaction(info.ssi_signo, NULL, &action);
80 if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
81 sigaction_invoke(&action, &info);
82 } else if (action.sa_handler) {
83 action.sa_handler(info.ssi_signo);
84 }
85 }
86}
87
88static int qemu_signal_init(Error **errp)
89{
90 int sigfd;
91 sigset_t set;
92
93
94
95
96
97
98 sigemptyset(&set);
99 sigaddset(&set, SIG_IPI);
100 sigaddset(&set, SIGIO);
101 sigaddset(&set, SIGALRM);
102 sigaddset(&set, SIGBUS);
103
104
105
106
107
108 pthread_sigmask(SIG_BLOCK, &set, NULL);
109
110 sigdelset(&set, SIG_IPI);
111 sigfd = qemu_signalfd(&set);
112 if (sigfd == -1) {
113 error_setg_errno(errp, errno, "failed to create signalfd");
114 return -errno;
115 }
116
117 fcntl_setfl(sigfd, O_NONBLOCK);
118
119 qemu_set_fd_handler(sigfd, sigfd_handler, NULL, (void *)(intptr_t)sigfd);
120
121 return 0;
122}
123
124#else
125
126static int qemu_signal_init(Error **errp)
127{
128 return 0;
129}
130#endif
131
132static AioContext *qemu_aio_context;
133static QEMUBH *qemu_notify_bh;
134
135static void notify_event_cb(void *opaque)
136{
137
138
139
140}
141
142AioContext *qemu_get_aio_context(void)
143{
144 return qemu_aio_context;
145}
146
147void qemu_notify_event(void)
148{
149 if (!qemu_aio_context) {
150 return;
151 }
152 qemu_bh_schedule(qemu_notify_bh);
153}
154
155static GArray *gpollfds;
156
157int qemu_init_main_loop(Error **errp)
158{
159 int ret;
160 GSource *src;
161
162 init_clocks(qemu_timer_notify_cb);
163
164 ret = qemu_signal_init(errp);
165 if (ret) {
166 return ret;
167 }
168
169 qemu_aio_context = aio_context_new(errp);
170 if (!qemu_aio_context) {
171 return -EMFILE;
172 }
173 qemu_set_current_aio_context(qemu_aio_context);
174 qemu_notify_bh = qemu_bh_new(notify_event_cb, NULL);
175 gpollfds = g_array_new(FALSE, FALSE, sizeof(GPollFD));
176 src = aio_get_g_source(qemu_aio_context);
177 g_source_set_name(src, "aio-context");
178 g_source_attach(src, NULL);
179 g_source_unref(src);
180 src = iohandler_get_g_source();
181 g_source_set_name(src, "io-handler");
182 g_source_attach(src, NULL);
183 g_source_unref(src);
184 return 0;
185}
186
187static int max_priority;
188
189#ifndef _WIN32
190static int glib_pollfds_idx;
191static int glib_n_poll_fds;
192
193void qemu_fd_register(int fd)
194{
195}
196
197static void glib_pollfds_fill(int64_t *cur_timeout)
198{
199 GMainContext *context = g_main_context_default();
200 int timeout = 0;
201 int64_t timeout_ns;
202 int n;
203
204 g_main_context_prepare(context, &max_priority);
205
206 glib_pollfds_idx = gpollfds->len;
207 n = glib_n_poll_fds;
208 do {
209 GPollFD *pfds;
210 glib_n_poll_fds = n;
211 g_array_set_size(gpollfds, glib_pollfds_idx + glib_n_poll_fds);
212 pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
213 n = g_main_context_query(context, max_priority, &timeout, pfds,
214 glib_n_poll_fds);
215 } while (n != glib_n_poll_fds);
216
217 if (timeout < 0) {
218 timeout_ns = -1;
219 } else {
220 timeout_ns = (int64_t)timeout * (int64_t)SCALE_MS;
221 }
222
223 *cur_timeout = qemu_soonest_timeout(timeout_ns, *cur_timeout);
224}
225
226static void glib_pollfds_poll(void)
227{
228 GMainContext *context = g_main_context_default();
229 GPollFD *pfds = &g_array_index(gpollfds, GPollFD, glib_pollfds_idx);
230
231 if (g_main_context_check(context, max_priority, pfds, glib_n_poll_fds)) {
232 g_main_context_dispatch(context);
233 }
234}
235
236#define MAX_MAIN_LOOP_SPIN (1000)
237
238static int os_host_main_loop_wait(int64_t timeout)
239{
240 GMainContext *context = g_main_context_default();
241 int ret;
242
243 g_main_context_acquire(context);
244
245 glib_pollfds_fill(&timeout);
246
247 qemu_mutex_unlock_iothread();
248 replay_mutex_unlock();
249
250 ret = qemu_poll_ns((GPollFD *)gpollfds->data, gpollfds->len, timeout);
251
252 replay_mutex_lock();
253 qemu_mutex_lock_iothread();
254
255 glib_pollfds_poll();
256
257 g_main_context_release(context);
258
259 return ret;
260}
261#else
262
263
264
265typedef struct PollingEntry {
266 PollingFunc *func;
267 void *opaque;
268 struct PollingEntry *next;
269} PollingEntry;
270
271static PollingEntry *first_polling_entry;
272
273int qemu_add_polling_cb(PollingFunc *func, void *opaque)
274{
275 PollingEntry **ppe, *pe;
276 pe = g_new0(PollingEntry, 1);
277 pe->func = func;
278 pe->opaque = opaque;
279 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next);
280 *ppe = pe;
281 return 0;
282}
283
284void qemu_del_polling_cb(PollingFunc *func, void *opaque)
285{
286 PollingEntry **ppe, *pe;
287 for(ppe = &first_polling_entry; *ppe != NULL; ppe = &(*ppe)->next) {
288 pe = *ppe;
289 if (pe->func == func && pe->opaque == opaque) {
290 *ppe = pe->next;
291 g_free(pe);
292 break;
293 }
294 }
295}
296
297
298
299typedef struct WaitObjects {
300 int num;
301 int revents[MAXIMUM_WAIT_OBJECTS + 1];
302 HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
303 WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
304 void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
305} WaitObjects;
306
307static WaitObjects wait_objects = {0};
308
309int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
310{
311 WaitObjects *w = &wait_objects;
312 if (w->num >= MAXIMUM_WAIT_OBJECTS) {
313 return -1;
314 }
315 w->events[w->num] = handle;
316 w->func[w->num] = func;
317 w->opaque[w->num] = opaque;
318 w->revents[w->num] = 0;
319 w->num++;
320 return 0;
321}
322
323void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
324{
325 int i, found;
326 WaitObjects *w = &wait_objects;
327
328 found = 0;
329 for (i = 0; i < w->num; i++) {
330 if (w->events[i] == handle) {
331 found = 1;
332 }
333 if (found) {
334 w->events[i] = w->events[i + 1];
335 w->func[i] = w->func[i + 1];
336 w->opaque[i] = w->opaque[i + 1];
337 w->revents[i] = w->revents[i + 1];
338 }
339 }
340 if (found) {
341 w->num--;
342 }
343}
344
345void qemu_fd_register(int fd)
346{
347 WSAEventSelect(fd, event_notifier_get_handle(&qemu_aio_context->notifier),
348 FD_READ | FD_ACCEPT | FD_CLOSE |
349 FD_CONNECT | FD_WRITE | FD_OOB);
350}
351
352static int pollfds_fill(GArray *pollfds, fd_set *rfds, fd_set *wfds,
353 fd_set *xfds)
354{
355 int nfds = -1;
356 int i;
357
358 for (i = 0; i < pollfds->len; i++) {
359 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
360 int fd = pfd->fd;
361 int events = pfd->events;
362 if (events & G_IO_IN) {
363 FD_SET(fd, rfds);
364 nfds = MAX(nfds, fd);
365 }
366 if (events & G_IO_OUT) {
367 FD_SET(fd, wfds);
368 nfds = MAX(nfds, fd);
369 }
370 if (events & G_IO_PRI) {
371 FD_SET(fd, xfds);
372 nfds = MAX(nfds, fd);
373 }
374 }
375 return nfds;
376}
377
378static void pollfds_poll(GArray *pollfds, int nfds, fd_set *rfds,
379 fd_set *wfds, fd_set *xfds)
380{
381 int i;
382
383 for (i = 0; i < pollfds->len; i++) {
384 GPollFD *pfd = &g_array_index(pollfds, GPollFD, i);
385 int fd = pfd->fd;
386 int revents = 0;
387
388 if (FD_ISSET(fd, rfds)) {
389 revents |= G_IO_IN;
390 }
391 if (FD_ISSET(fd, wfds)) {
392 revents |= G_IO_OUT;
393 }
394 if (FD_ISSET(fd, xfds)) {
395 revents |= G_IO_PRI;
396 }
397 pfd->revents = revents & pfd->events;
398 }
399}
400
401static int os_host_main_loop_wait(int64_t timeout)
402{
403 GMainContext *context = g_main_context_default();
404 GPollFD poll_fds[1024 * 2];
405 int select_ret = 0;
406 int g_poll_ret, ret, i, n_poll_fds;
407 PollingEntry *pe;
408 WaitObjects *w = &wait_objects;
409 gint poll_timeout;
410 int64_t poll_timeout_ns;
411 static struct timeval tv0;
412 fd_set rfds, wfds, xfds;
413 int nfds;
414
415 g_main_context_acquire(context);
416
417
418 ret = 0;
419 for (pe = first_polling_entry; pe != NULL; pe = pe->next) {
420 ret |= pe->func(pe->opaque);
421 }
422 if (ret != 0) {
423 g_main_context_release(context);
424 return ret;
425 }
426
427 FD_ZERO(&rfds);
428 FD_ZERO(&wfds);
429 FD_ZERO(&xfds);
430 nfds = pollfds_fill(gpollfds, &rfds, &wfds, &xfds);
431 if (nfds >= 0) {
432 select_ret = select(nfds + 1, &rfds, &wfds, &xfds, &tv0);
433 if (select_ret != 0) {
434 timeout = 0;
435 }
436 if (select_ret > 0) {
437 pollfds_poll(gpollfds, nfds, &rfds, &wfds, &xfds);
438 }
439 }
440
441 g_main_context_prepare(context, &max_priority);
442 n_poll_fds = g_main_context_query(context, max_priority, &poll_timeout,
443 poll_fds, ARRAY_SIZE(poll_fds));
444 g_assert(n_poll_fds + w->num <= ARRAY_SIZE(poll_fds));
445
446 for (i = 0; i < w->num; i++) {
447 poll_fds[n_poll_fds + i].fd = (DWORD_PTR)w->events[i];
448 poll_fds[n_poll_fds + i].events = G_IO_IN;
449 }
450
451 if (poll_timeout < 0) {
452 poll_timeout_ns = -1;
453 } else {
454 poll_timeout_ns = (int64_t)poll_timeout * (int64_t)SCALE_MS;
455 }
456
457 poll_timeout_ns = qemu_soonest_timeout(poll_timeout_ns, timeout);
458
459 qemu_mutex_unlock_iothread();
460
461 replay_mutex_unlock();
462
463 g_poll_ret = qemu_poll_ns(poll_fds, n_poll_fds + w->num, poll_timeout_ns);
464
465 replay_mutex_lock();
466
467 qemu_mutex_lock_iothread();
468 if (g_poll_ret > 0) {
469 for (i = 0; i < w->num; i++) {
470 w->revents[i] = poll_fds[n_poll_fds + i].revents;
471 }
472 for (i = 0; i < w->num; i++) {
473 if (w->revents[i] && w->func[i]) {
474 w->func[i](w->opaque[i]);
475 }
476 }
477 }
478
479 if (g_main_context_check(context, max_priority, poll_fds, n_poll_fds)) {
480 g_main_context_dispatch(context);
481 }
482
483 g_main_context_release(context);
484
485 return select_ret || g_poll_ret;
486}
487#endif
488
489static NotifierList main_loop_poll_notifiers =
490 NOTIFIER_LIST_INITIALIZER(main_loop_poll_notifiers);
491
492void main_loop_poll_add_notifier(Notifier *notify)
493{
494 notifier_list_add(&main_loop_poll_notifiers, notify);
495}
496
497void main_loop_poll_remove_notifier(Notifier *notify)
498{
499 notifier_remove(notify);
500}
501
502void main_loop_wait(int nonblocking)
503{
504 MainLoopPoll mlpoll = {
505 .state = MAIN_LOOP_POLL_FILL,
506 .timeout = UINT32_MAX,
507 .pollfds = gpollfds,
508 };
509 int ret;
510 int64_t timeout_ns;
511
512 if (nonblocking) {
513 mlpoll.timeout = 0;
514 }
515
516
517 g_array_set_size(gpollfds, 0);
518
519 notifier_list_notify(&main_loop_poll_notifiers, &mlpoll);
520
521 if (mlpoll.timeout == UINT32_MAX) {
522 timeout_ns = -1;
523 } else {
524 timeout_ns = (uint64_t)mlpoll.timeout * (int64_t)(SCALE_MS);
525 }
526
527 timeout_ns = qemu_soonest_timeout(timeout_ns,
528 timerlistgroup_deadline_ns(
529 &main_loop_tlg));
530
531 ret = os_host_main_loop_wait(timeout_ns);
532 mlpoll.state = ret < 0 ? MAIN_LOOP_POLL_ERR : MAIN_LOOP_POLL_OK;
533 notifier_list_notify(&main_loop_poll_notifiers, &mlpoll);
534
535 if (icount_enabled()) {
536
537
538
539
540 icount_start_warp_timer();
541 }
542 qemu_clock_run_all_timers();
543}
544
545
546
547QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name)
548{
549 return aio_bh_new_full(qemu_aio_context, cb, opaque, name);
550}
551
552
553
554
555
556
557static AioContext *iohandler_ctx;
558
559static void iohandler_init(void)
560{
561 if (!iohandler_ctx) {
562 iohandler_ctx = aio_context_new(&error_abort);
563 }
564}
565
566AioContext *iohandler_get_aio_context(void)
567{
568 iohandler_init();
569 return iohandler_ctx;
570}
571
572GSource *iohandler_get_g_source(void)
573{
574 iohandler_init();
575 return aio_get_g_source(iohandler_ctx);
576}
577
578void qemu_set_fd_handler(int fd,
579 IOHandler *fd_read,
580 IOHandler *fd_write,
581 void *opaque)
582{
583 iohandler_init();
584 aio_set_fd_handler(iohandler_ctx, fd, false,
585 fd_read, fd_write, NULL, NULL, opaque);
586}
587
588void event_notifier_set_handler(EventNotifier *e,
589 EventNotifierHandler *handler)
590{
591 iohandler_init();
592 aio_set_event_notifier(iohandler_ctx, e, false,
593 handler, NULL, NULL);
594}
595