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17#include <linux/kernel.h>
18#include <linux/sched.h>
19#include <linux/syscalls.h>
20#include <linux/module.h>
21#include <linux/slab.h>
22#include <linux/poll.h>
23#include <linux/personality.h>
24#include <linux/file.h>
25#include <linux/fdtable.h>
26#include <linux/fs.h>
27#include <linux/rcupdate.h>
28#include <linux/hrtimer.h>
29
30#include <asm/uaccess.h>
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45#define MAX_SLACK (100 * NSEC_PER_MSEC)
46
47static long __estimate_accuracy(struct timespec *tv)
48{
49 long slack;
50 int divfactor = 1000;
51
52 if (tv->tv_sec < 0)
53 return 0;
54
55 if (task_nice(current) > 0)
56 divfactor = divfactor / 5;
57
58 if (tv->tv_sec > MAX_SLACK / (NSEC_PER_SEC/divfactor))
59 return MAX_SLACK;
60
61 slack = tv->tv_nsec / divfactor;
62 slack += tv->tv_sec * (NSEC_PER_SEC/divfactor);
63
64 if (slack > MAX_SLACK)
65 return MAX_SLACK;
66
67 return slack;
68}
69
70long select_estimate_accuracy(struct timespec *tv)
71{
72 unsigned long ret;
73 struct timespec now;
74
75
76
77
78
79 if (rt_task(current))
80 return 0;
81
82 ktime_get_ts(&now);
83 now = timespec_sub(*tv, now);
84 ret = __estimate_accuracy(&now);
85 if (ret < current->timer_slack_ns)
86 return current->timer_slack_ns;
87 return ret;
88}
89
90
91
92struct poll_table_page {
93 struct poll_table_page * next;
94 struct poll_table_entry * entry;
95 struct poll_table_entry entries[0];
96};
97
98#define POLL_TABLE_FULL(table) \
99 ((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table))
100
101
102
103
104
105
106
107
108
109
110
111
112
113static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
114 poll_table *p);
115
116void poll_initwait(struct poll_wqueues *pwq)
117{
118 init_poll_funcptr(&pwq->pt, __pollwait);
119 pwq->polling_task = current;
120 pwq->triggered = 0;
121 pwq->error = 0;
122 pwq->table = NULL;
123 pwq->inline_index = 0;
124}
125EXPORT_SYMBOL(poll_initwait);
126
127static void free_poll_entry(struct poll_table_entry *entry)
128{
129 remove_wait_queue(entry->wait_address, &entry->wait);
130 fput(entry->filp);
131}
132
133void poll_freewait(struct poll_wqueues *pwq)
134{
135 struct poll_table_page * p = pwq->table;
136 int i;
137 for (i = 0; i < pwq->inline_index; i++)
138 free_poll_entry(pwq->inline_entries + i);
139 while (p) {
140 struct poll_table_entry * entry;
141 struct poll_table_page *old;
142
143 entry = p->entry;
144 do {
145 entry--;
146 free_poll_entry(entry);
147 } while (entry > p->entries);
148 old = p;
149 p = p->next;
150 free_page((unsigned long) old);
151 }
152}
153EXPORT_SYMBOL(poll_freewait);
154
155static struct poll_table_entry *poll_get_entry(struct poll_wqueues *p)
156{
157 struct poll_table_page *table = p->table;
158
159 if (p->inline_index < N_INLINE_POLL_ENTRIES)
160 return p->inline_entries + p->inline_index++;
161
162 if (!table || POLL_TABLE_FULL(table)) {
163 struct poll_table_page *new_table;
164
165 new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL);
166 if (!new_table) {
167 p->error = -ENOMEM;
168 return NULL;
169 }
170 new_table->entry = new_table->entries;
171 new_table->next = table;
172 p->table = new_table;
173 table = new_table;
174 }
175
176 return table->entry++;
177}
178
179static int __pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key)
180{
181 struct poll_wqueues *pwq = wait->private;
182 DECLARE_WAITQUEUE(dummy_wait, pwq->polling_task);
183
184
185
186
187
188
189
190
191 smp_wmb();
192 pwq->triggered = 1;
193
194
195
196
197
198
199
200
201
202 return default_wake_function(&dummy_wait, mode, sync, key);
203}
204
205static int pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key)
206{
207 struct poll_table_entry *entry;
208
209 entry = container_of(wait, struct poll_table_entry, wait);
210 if (key && !((unsigned long)key & entry->key))
211 return 0;
212 return __pollwake(wait, mode, sync, key);
213}
214
215
216static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
217 poll_table *p)
218{
219 struct poll_wqueues *pwq = container_of(p, struct poll_wqueues, pt);
220 struct poll_table_entry *entry = poll_get_entry(pwq);
221 if (!entry)
222 return;
223 get_file(filp);
224 entry->filp = filp;
225 entry->wait_address = wait_address;
226 entry->key = p->key;
227 init_waitqueue_func_entry(&entry->wait, pollwake);
228 entry->wait.private = pwq;
229 add_wait_queue(wait_address, &entry->wait);
230}
231
232int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
233 ktime_t *expires, unsigned long slack)
234{
235 int rc = -EINTR;
236
237 set_current_state(state);
238 if (!pwq->triggered)
239 rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS);
240 __set_current_state(TASK_RUNNING);
241
242
243
244
245
246
247
248
249
250
251
252
253 set_mb(pwq->triggered, 0);
254
255 return rc;
256}
257EXPORT_SYMBOL(poll_schedule_timeout);
258
259
260
261
262
263
264
265
266
267
268
269
270int poll_select_set_timeout(struct timespec *to, long sec, long nsec)
271{
272 struct timespec ts = {.tv_sec = sec, .tv_nsec = nsec};
273
274 if (!timespec_valid(&ts))
275 return -EINVAL;
276
277
278 if (!sec && !nsec) {
279 to->tv_sec = to->tv_nsec = 0;
280 } else {
281 ktime_get_ts(to);
282 *to = timespec_add_safe(*to, ts);
283 }
284 return 0;
285}
286
287static int poll_select_copy_remaining(struct timespec *end_time, void __user *p,
288 int timeval, int ret)
289{
290 struct timespec rts;
291 struct timeval rtv;
292
293 if (!p)
294 return ret;
295
296 if (current->personality & STICKY_TIMEOUTS)
297 goto sticky;
298
299
300 if (!end_time->tv_sec && !end_time->tv_nsec)
301 return ret;
302
303 ktime_get_ts(&rts);
304 rts = timespec_sub(*end_time, rts);
305 if (rts.tv_sec < 0)
306 rts.tv_sec = rts.tv_nsec = 0;
307
308 if (timeval) {
309 if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
310 memset(&rtv, 0, sizeof(rtv));
311 rtv.tv_sec = rts.tv_sec;
312 rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC;
313
314 if (!copy_to_user(p, &rtv, sizeof(rtv)))
315 return ret;
316
317 } else if (!copy_to_user(p, &rts, sizeof(rts)))
318 return ret;
319
320
321
322
323
324
325
326
327
328sticky:
329 if (ret == -ERESTARTNOHAND)
330 ret = -EINTR;
331 return ret;
332}
333
334#define FDS_IN(fds, n) (fds->in + n)
335#define FDS_OUT(fds, n) (fds->out + n)
336#define FDS_EX(fds, n) (fds->ex + n)
337
338#define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n))
339
340static int max_select_fd(unsigned long n, fd_set_bits *fds)
341{
342 unsigned long *open_fds;
343 unsigned long set;
344 int max;
345 struct fdtable *fdt;
346
347
348 set = ~(~0UL << (n & (__NFDBITS-1)));
349 n /= __NFDBITS;
350 fdt = files_fdtable(current->files);
351 open_fds = fdt->open_fds->fds_bits+n;
352 max = 0;
353 if (set) {
354 set &= BITS(fds, n);
355 if (set) {
356 if (!(set & ~*open_fds))
357 goto get_max;
358 return -EBADF;
359 }
360 }
361 while (n) {
362 open_fds--;
363 n--;
364 set = BITS(fds, n);
365 if (!set)
366 continue;
367 if (set & ~*open_fds)
368 return -EBADF;
369 if (max)
370 continue;
371get_max:
372 do {
373 max++;
374 set >>= 1;
375 } while (set);
376 max += n * __NFDBITS;
377 }
378
379 return max;
380}
381
382#define POLLIN_SET (POLLRDNORM | POLLRDBAND | POLLIN | POLLHUP | POLLERR)
383#define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR)
384#define POLLEX_SET (POLLPRI)
385
386static inline void wait_key_set(poll_table *wait, unsigned long in,
387 unsigned long out, unsigned long bit)
388{
389 if (wait) {
390 wait->key = POLLEX_SET;
391 if (in & bit)
392 wait->key |= POLLIN_SET;
393 if (out & bit)
394 wait->key |= POLLOUT_SET;
395 }
396}
397
398int do_select(int n, fd_set_bits *fds, struct timespec *end_time)
399{
400 ktime_t expire, *to = NULL;
401 struct poll_wqueues table;
402 poll_table *wait;
403 int retval, i, timed_out = 0;
404 unsigned long slack = 0;
405
406 rcu_read_lock();
407 retval = max_select_fd(n, fds);
408 rcu_read_unlock();
409
410 if (retval < 0)
411 return retval;
412 n = retval;
413
414 poll_initwait(&table);
415 wait = &table.pt;
416 if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
417 wait = NULL;
418 timed_out = 1;
419 }
420
421 if (end_time && !timed_out)
422 slack = select_estimate_accuracy(end_time);
423
424 retval = 0;
425 for (;;) {
426 unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp;
427
428 inp = fds->in; outp = fds->out; exp = fds->ex;
429 rinp = fds->res_in; routp = fds->res_out; rexp = fds->res_ex;
430
431 for (i = 0; i < n; ++rinp, ++routp, ++rexp) {
432 unsigned long in, out, ex, all_bits, bit = 1, mask, j;
433 unsigned long res_in = 0, res_out = 0, res_ex = 0;
434 const struct file_operations *f_op = NULL;
435 struct file *file = NULL;
436
437 in = *inp++; out = *outp++; ex = *exp++;
438 all_bits = in | out | ex;
439 if (all_bits == 0) {
440 i += __NFDBITS;
441 continue;
442 }
443
444 for (j = 0; j < __NFDBITS; ++j, ++i, bit <<= 1) {
445 int fput_needed;
446 if (i >= n)
447 break;
448 if (!(bit & all_bits))
449 continue;
450 file = fget_light(i, &fput_needed);
451 if (file) {
452 f_op = file->f_op;
453 mask = DEFAULT_POLLMASK;
454 if (f_op && f_op->poll) {
455 wait_key_set(wait, in, out, bit);
456 mask = (*f_op->poll)(file, wait);
457 }
458 fput_light(file, fput_needed);
459 if ((mask & POLLIN_SET) && (in & bit)) {
460 res_in |= bit;
461 retval++;
462 wait = NULL;
463 }
464 if ((mask & POLLOUT_SET) && (out & bit)) {
465 res_out |= bit;
466 retval++;
467 wait = NULL;
468 }
469 if ((mask & POLLEX_SET) && (ex & bit)) {
470 res_ex |= bit;
471 retval++;
472 wait = NULL;
473 }
474 }
475 }
476 if (res_in)
477 *rinp = res_in;
478 if (res_out)
479 *routp = res_out;
480 if (res_ex)
481 *rexp = res_ex;
482 cond_resched();
483 }
484 wait = NULL;
485 if (retval || timed_out || signal_pending(current))
486 break;
487 if (table.error) {
488 retval = table.error;
489 break;
490 }
491
492
493
494
495
496
497 if (end_time && !to) {
498 expire = timespec_to_ktime(*end_time);
499 to = &expire;
500 }
501
502 if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE,
503 to, slack))
504 timed_out = 1;
505 }
506
507 poll_freewait(&table);
508
509 return retval;
510}
511
512
513
514
515
516
517
518
519
520#define MAX_SELECT_SECONDS \
521 ((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1)
522
523int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
524 fd_set __user *exp, struct timespec *end_time)
525{
526 fd_set_bits fds;
527 void *bits;
528 int ret, max_fds;
529 unsigned int size;
530 struct fdtable *fdt;
531
532 long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
533
534 ret = -EINVAL;
535 if (n < 0)
536 goto out_nofds;
537
538
539 rcu_read_lock();
540 fdt = files_fdtable(current->files);
541 max_fds = fdt->max_fds;
542 rcu_read_unlock();
543 if (n > max_fds)
544 n = max_fds;
545
546
547
548
549
550
551 size = FDS_BYTES(n);
552 bits = stack_fds;
553 if (size > sizeof(stack_fds) / 6) {
554
555 ret = -ENOMEM;
556 bits = kmalloc(6 * size, GFP_KERNEL);
557 if (!bits)
558 goto out_nofds;
559 }
560 fds.in = bits;
561 fds.out = bits + size;
562 fds.ex = bits + 2*size;
563 fds.res_in = bits + 3*size;
564 fds.res_out = bits + 4*size;
565 fds.res_ex = bits + 5*size;
566
567 if ((ret = get_fd_set(n, inp, fds.in)) ||
568 (ret = get_fd_set(n, outp, fds.out)) ||
569 (ret = get_fd_set(n, exp, fds.ex)))
570 goto out;
571 zero_fd_set(n, fds.res_in);
572 zero_fd_set(n, fds.res_out);
573 zero_fd_set(n, fds.res_ex);
574
575 ret = do_select(n, &fds, end_time);
576
577 if (ret < 0)
578 goto out;
579 if (!ret) {
580 ret = -ERESTARTNOHAND;
581 if (signal_pending(current))
582 goto out;
583 ret = 0;
584 }
585
586 if (set_fd_set(n, inp, fds.res_in) ||
587 set_fd_set(n, outp, fds.res_out) ||
588 set_fd_set(n, exp, fds.res_ex))
589 ret = -EFAULT;
590
591out:
592 if (bits != stack_fds)
593 kfree(bits);
594out_nofds:
595 return ret;
596}
597
598SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp,
599 fd_set __user *, exp, struct timeval __user *, tvp)
600{
601 struct timespec end_time, *to = NULL;
602 struct timeval tv;
603 int ret;
604
605 if (tvp) {
606 if (copy_from_user(&tv, tvp, sizeof(tv)))
607 return -EFAULT;
608
609 to = &end_time;
610 if (poll_select_set_timeout(to,
611 tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
612 (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
613 return -EINVAL;
614 }
615
616 ret = core_sys_select(n, inp, outp, exp, to);
617 ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
618
619 return ret;
620}
621
622#ifdef HAVE_SET_RESTORE_SIGMASK
623static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp,
624 fd_set __user *exp, struct timespec __user *tsp,
625 const sigset_t __user *sigmask, size_t sigsetsize)
626{
627 sigset_t ksigmask, sigsaved;
628 struct timespec ts, end_time, *to = NULL;
629 int ret;
630
631 if (tsp) {
632 if (copy_from_user(&ts, tsp, sizeof(ts)))
633 return -EFAULT;
634
635 to = &end_time;
636 if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
637 return -EINVAL;
638 }
639
640 if (sigmask) {
641
642 if (sigsetsize != sizeof(sigset_t))
643 return -EINVAL;
644 if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask)))
645 return -EFAULT;
646
647 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
648 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
649 }
650
651 ret = core_sys_select(n, inp, outp, exp, to);
652 ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
653
654 if (ret == -ERESTARTNOHAND) {
655
656
657
658
659
660 if (sigmask) {
661 memcpy(¤t->saved_sigmask, &sigsaved,
662 sizeof(sigsaved));
663 set_restore_sigmask();
664 }
665 } else if (sigmask)
666 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
667
668 return ret;
669}
670
671
672
673
674
675
676
677SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp,
678 fd_set __user *, exp, struct timespec __user *, tsp,
679 void __user *, sig)
680{
681 size_t sigsetsize = 0;
682 sigset_t __user *up = NULL;
683
684 if (sig) {
685 if (!access_ok(VERIFY_READ, sig, sizeof(void *)+sizeof(size_t))
686 || __get_user(up, (sigset_t __user * __user *)sig)
687 || __get_user(sigsetsize,
688 (size_t __user *)(sig+sizeof(void *))))
689 return -EFAULT;
690 }
691
692 return do_pselect(n, inp, outp, exp, tsp, up, sigsetsize);
693}
694#endif
695
696#ifdef __ARCH_WANT_SYS_OLD_SELECT
697struct sel_arg_struct {
698 unsigned long n;
699 fd_set __user *inp, *outp, *exp;
700 struct timeval __user *tvp;
701};
702
703SYSCALL_DEFINE1(old_select, struct sel_arg_struct __user *, arg)
704{
705 struct sel_arg_struct a;
706
707 if (copy_from_user(&a, arg, sizeof(a)))
708 return -EFAULT;
709 return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
710}
711#endif
712
713struct poll_list {
714 struct poll_list *next;
715 int len;
716 struct pollfd entries[0];
717};
718
719#define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))
720
721
722
723
724
725
726
727
728static inline unsigned int do_pollfd(struct pollfd *pollfd, poll_table *pwait)
729{
730 unsigned int mask;
731 int fd;
732
733 mask = 0;
734 fd = pollfd->fd;
735 if (fd >= 0) {
736 int fput_needed;
737 struct file * file;
738
739 file = fget_light(fd, &fput_needed);
740 mask = POLLNVAL;
741 if (file != NULL) {
742 mask = DEFAULT_POLLMASK;
743 if (file->f_op && file->f_op->poll) {
744 if (pwait)
745 pwait->key = pollfd->events |
746 POLLERR | POLLHUP;
747 mask = file->f_op->poll(file, pwait);
748 }
749
750 mask &= pollfd->events | POLLERR | POLLHUP;
751 fput_light(file, fput_needed);
752 }
753 }
754 pollfd->revents = mask;
755
756 return mask;
757}
758
759static int do_poll(unsigned int nfds, struct poll_list *list,
760 struct poll_wqueues *wait, struct timespec *end_time)
761{
762 poll_table* pt = &wait->pt;
763 ktime_t expire, *to = NULL;
764 int timed_out = 0, count = 0;
765 unsigned long slack = 0;
766
767
768 if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
769 pt = NULL;
770 timed_out = 1;
771 }
772
773 if (end_time && !timed_out)
774 slack = select_estimate_accuracy(end_time);
775
776 for (;;) {
777 struct poll_list *walk;
778
779 for (walk = list; walk != NULL; walk = walk->next) {
780 struct pollfd * pfd, * pfd_end;
781
782 pfd = walk->entries;
783 pfd_end = pfd + walk->len;
784 for (; pfd != pfd_end; pfd++) {
785
786
787
788
789
790
791
792 if (do_pollfd(pfd, pt)) {
793 count++;
794 pt = NULL;
795 }
796 }
797 }
798
799
800
801
802 pt = NULL;
803 if (!count) {
804 count = wait->error;
805 if (signal_pending(current))
806 count = -EINTR;
807 }
808 if (count || timed_out)
809 break;
810
811
812
813
814
815
816 if (end_time && !to) {
817 expire = timespec_to_ktime(*end_time);
818 to = &expire;
819 }
820
821 if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack))
822 timed_out = 1;
823 }
824 return count;
825}
826
827#define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \
828 sizeof(struct pollfd))
829
830int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
831 struct timespec *end_time)
832{
833 struct poll_wqueues table;
834 int err = -EFAULT, fdcount, len, size;
835
836
837
838 long stack_pps[POLL_STACK_ALLOC/sizeof(long)];
839 struct poll_list *const head = (struct poll_list *)stack_pps;
840 struct poll_list *walk = head;
841 unsigned long todo = nfds;
842
843 if (nfds > rlimit(RLIMIT_NOFILE))
844 return -EINVAL;
845
846 len = min_t(unsigned int, nfds, N_STACK_PPS);
847 for (;;) {
848 walk->next = NULL;
849 walk->len = len;
850 if (!len)
851 break;
852
853 if (copy_from_user(walk->entries, ufds + nfds-todo,
854 sizeof(struct pollfd) * walk->len))
855 goto out_fds;
856
857 todo -= walk->len;
858 if (!todo)
859 break;
860
861 len = min(todo, POLLFD_PER_PAGE);
862 size = sizeof(struct poll_list) + sizeof(struct pollfd) * len;
863 walk = walk->next = kmalloc(size, GFP_KERNEL);
864 if (!walk) {
865 err = -ENOMEM;
866 goto out_fds;
867 }
868 }
869
870 poll_initwait(&table);
871 fdcount = do_poll(nfds, head, &table, end_time);
872 poll_freewait(&table);
873
874 for (walk = head; walk; walk = walk->next) {
875 struct pollfd *fds = walk->entries;
876 int j;
877
878 for (j = 0; j < walk->len; j++, ufds++)
879 if (__put_user(fds[j].revents, &ufds->revents))
880 goto out_fds;
881 }
882
883 err = fdcount;
884out_fds:
885 walk = head->next;
886 while (walk) {
887 struct poll_list *pos = walk;
888 walk = walk->next;
889 kfree(pos);
890 }
891
892 return err;
893}
894
895static long do_restart_poll(struct restart_block *restart_block)
896{
897 struct pollfd __user *ufds = restart_block->poll.ufds;
898 int nfds = restart_block->poll.nfds;
899 struct timespec *to = NULL, end_time;
900 int ret;
901
902 if (restart_block->poll.has_timeout) {
903 end_time.tv_sec = restart_block->poll.tv_sec;
904 end_time.tv_nsec = restart_block->poll.tv_nsec;
905 to = &end_time;
906 }
907
908 ret = do_sys_poll(ufds, nfds, to);
909
910 if (ret == -EINTR) {
911 restart_block->fn = do_restart_poll;
912 ret = -ERESTART_RESTARTBLOCK;
913 }
914 return ret;
915}
916
917SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
918 long, timeout_msecs)
919{
920 struct timespec end_time, *to = NULL;
921 int ret;
922
923 if (timeout_msecs >= 0) {
924 to = &end_time;
925 poll_select_set_timeout(to, timeout_msecs / MSEC_PER_SEC,
926 NSEC_PER_MSEC * (timeout_msecs % MSEC_PER_SEC));
927 }
928
929 ret = do_sys_poll(ufds, nfds, to);
930
931 if (ret == -EINTR) {
932 struct restart_block *restart_block;
933
934 restart_block = ¤t_thread_info()->restart_block;
935 restart_block->fn = do_restart_poll;
936 restart_block->poll.ufds = ufds;
937 restart_block->poll.nfds = nfds;
938
939 if (timeout_msecs >= 0) {
940 restart_block->poll.tv_sec = end_time.tv_sec;
941 restart_block->poll.tv_nsec = end_time.tv_nsec;
942 restart_block->poll.has_timeout = 1;
943 } else
944 restart_block->poll.has_timeout = 0;
945
946 ret = -ERESTART_RESTARTBLOCK;
947 }
948 return ret;
949}
950
951#ifdef HAVE_SET_RESTORE_SIGMASK
952SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
953 struct timespec __user *, tsp, const sigset_t __user *, sigmask,
954 size_t, sigsetsize)
955{
956 sigset_t ksigmask, sigsaved;
957 struct timespec ts, end_time, *to = NULL;
958 int ret;
959
960 if (tsp) {
961 if (copy_from_user(&ts, tsp, sizeof(ts)))
962 return -EFAULT;
963
964 to = &end_time;
965 if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
966 return -EINVAL;
967 }
968
969 if (sigmask) {
970
971 if (sigsetsize != sizeof(sigset_t))
972 return -EINVAL;
973 if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask)))
974 return -EFAULT;
975
976 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
977 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
978 }
979
980 ret = do_sys_poll(ufds, nfds, to);
981
982
983 if (ret == -EINTR) {
984
985
986
987
988
989 if (sigmask) {
990 memcpy(¤t->saved_sigmask, &sigsaved,
991 sizeof(sigsaved));
992 set_restore_sigmask();
993 }
994 ret = -ERESTARTNOHAND;
995 } else if (sigmask)
996 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
997
998 ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
999
1000 return ret;
1001}
1002#endif
1003