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Linux 4.14.161
[linux/fpc-iii.git] / fs / select.c
blob063067e606ca76bc2cedb098fe774a14d1cd6c9b
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * This file contains the procedures for the handling of select and poll
4 *
5 * Created for Linux based loosely upon Mathius Lattner's minix
6 * patches by Peter MacDonald. Heavily edited by Linus.
7 *
8 * 4 February 1994
9 * COFF/ELF binary emulation. If the process has the STICKY_TIMEOUTS
10 * flag set in its personality we do *not* modify the given timeout
11 * parameter to reflect time remaining.
12 *
13 * 24 January 2000
14 * Changed sys_poll()/do_poll() to use PAGE_SIZE chunk-based allocation
15 * of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian).
16 */
17
18 #include <linux/kernel.h>
19 #include <linux/sched/signal.h>
20 #include <linux/sched/rt.h>
21 #include <linux/syscalls.h>
22 #include <linux/export.h>
23 #include <linux/slab.h>
24 #include <linux/poll.h>
25 #include <linux/personality.h> /* for STICKY_TIMEOUTS */
26 #include <linux/file.h>
27 #include <linux/fdtable.h>
28 #include <linux/fs.h>
29 #include <linux/rcupdate.h>
30 #include <linux/hrtimer.h>
31 #include <linux/freezer.h>
32 #include <net/busy_poll.h>
33 #include <linux/vmalloc.h>
34
35 #include <linux/uaccess.h>
36
37
38 /*
39 * Estimate expected accuracy in ns from a timeval.
40 *
41 * After quite a bit of churning around, we've settled on
42 * a simple thing of taking 0.1% of the timeout as the
43 * slack, with a cap of 100 msec.
44 * "nice" tasks get a 0.5% slack instead.
45 *
46 * Consider this comment an open invitation to come up with even
47 * better solutions..
48 */
49
50 #define MAX_SLACK (100 * NSEC_PER_MSEC)
51
52 static long __estimate_accuracy(struct timespec64 *tv)
53 {
54 long slack;
55 int divfactor = 1000;
56
57 if (tv->tv_sec < 0)
58 return 0;
59
60 if (task_nice(current) > 0)
61 divfactor = divfactor / 5;
62
63 if (tv->tv_sec > MAX_SLACK / (NSEC_PER_SEC/divfactor))
64 return MAX_SLACK;
65
66 slack = tv->tv_nsec / divfactor;
67 slack += tv->tv_sec * (NSEC_PER_SEC/divfactor);
68
69 if (slack > MAX_SLACK)
70 return MAX_SLACK;
71
72 return slack;
73 }
74
75 u64 select_estimate_accuracy(struct timespec64 *tv)
76 {
77 u64 ret;
78 struct timespec64 now;
79
80 /*
81 * Realtime tasks get a slack of 0 for obvious reasons.
82 */
83
84 if (rt_task(current))
85 return 0;
86
87 ktime_get_ts64(&now);
88 now = timespec64_sub(*tv, now);
89 ret = __estimate_accuracy(&now);
90 if (ret < current->timer_slack_ns)
91 return current->timer_slack_ns;
92 return ret;
93 }
94
95
96
97 struct poll_table_page {
98 struct poll_table_page * next;
99 struct poll_table_entry * entry;
100 struct poll_table_entry entries[0];
101 };
102
103 #define POLL_TABLE_FULL(table) \
104 ((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table))
105
106 /*
107 * Ok, Peter made a complicated, but straightforward multiple_wait() function.
108 * I have rewritten this, taking some shortcuts: This code may not be easy to
109 * follow, but it should be free of race-conditions, and it's practical. If you
110 * understand what I'm doing here, then you understand how the linux
111 * sleep/wakeup mechanism works.
112 *
113 * Two very simple procedures, poll_wait() and poll_freewait() make all the
114 * work. poll_wait() is an inline-function defined in <linux/poll.h>,
115 * as all select/poll functions have to call it to add an entry to the
116 * poll table.
117 */
118 static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
119 poll_table *p);
120
121 void poll_initwait(struct poll_wqueues *pwq)
122 {
123 init_poll_funcptr(&pwq->pt, __pollwait);
124 pwq->polling_task = current;
125 pwq->triggered = 0;
126 pwq->error = 0;
127 pwq->table = NULL;
128 pwq->inline_index = 0;
129 }
130 EXPORT_SYMBOL(poll_initwait);
131
132 static void free_poll_entry(struct poll_table_entry *entry)
133 {
134 remove_wait_queue(entry->wait_address, &entry->wait);
135 fput(entry->filp);
136 }
137
138 void poll_freewait(struct poll_wqueues *pwq)
139 {
140 struct poll_table_page * p = pwq->table;
141 int i;
142 for (i = 0; i < pwq->inline_index; i++)
143 free_poll_entry(pwq->inline_entries + i);
144 while (p) {
145 struct poll_table_entry * entry;
146 struct poll_table_page *old;
147
148 entry = p->entry;
149 do {
150 entry--;
151 free_poll_entry(entry);
152 } while (entry > p->entries);
153 old = p;
154 p = p->next;
155 free_page((unsigned long) old);
156 }
157 }
158 EXPORT_SYMBOL(poll_freewait);
159
160 static struct poll_table_entry *poll_get_entry(struct poll_wqueues *p)
161 {
162 struct poll_table_page *table = p->table;
163
164 if (p->inline_index < N_INLINE_POLL_ENTRIES)
165 return p->inline_entries + p->inline_index++;
166
167 if (!table || POLL_TABLE_FULL(table)) {
168 struct poll_table_page *new_table;
169
170 new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL);
171 if (!new_table) {
172 p->error = -ENOMEM;
173 return NULL;
174 }
175 new_table->entry = new_table->entries;
176 new_table->next = table;
177 p->table = new_table;
178 table = new_table;
179 }
180
181 return table->entry++;
182 }
183
184 static int __pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
185 {
186 struct poll_wqueues *pwq = wait->private;
187 DECLARE_WAITQUEUE(dummy_wait, pwq->polling_task);
188
189 /*
190 * Although this function is called under waitqueue lock, LOCK
191 * doesn't imply write barrier and the users expect write
192 * barrier semantics on wakeup functions. The following
193 * smp_wmb() is equivalent to smp_wmb() in try_to_wake_up()
194 * and is paired with smp_store_mb() in poll_schedule_timeout.
195 */
196 smp_wmb();
197 pwq->triggered = 1;
198
199 /*
200 * Perform the default wake up operation using a dummy
201 * waitqueue.
202 *
203 * TODO: This is hacky but there currently is no interface to
204 * pass in @sync. @sync is scheduled to be removed and once
205 * that happens, wake_up_process() can be used directly.
206 */
207 return default_wake_function(&dummy_wait, mode, sync, key);
208 }
209
210 static int pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
211 {
212 struct poll_table_entry *entry;
213
214 entry = container_of(wait, struct poll_table_entry, wait);
215 if (key && !((unsigned long)key & entry->key))
216 return 0;
217 return __pollwake(wait, mode, sync, key);
218 }
219
220 /* Add a new entry */
221 static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
222 poll_table *p)
223 {
224 struct poll_wqueues *pwq = container_of(p, struct poll_wqueues, pt);
225 struct poll_table_entry *entry = poll_get_entry(pwq);
226 if (!entry)
227 return;
228 entry->filp = get_file(filp);
229 entry->wait_address = wait_address;
230 entry->key = p->_key;
231 init_waitqueue_func_entry(&entry->wait, pollwake);
232 entry->wait.private = pwq;
233 add_wait_queue(wait_address, &entry->wait);
234 }
235
236 int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
237 ktime_t *expires, unsigned long slack)
238 {
239 int rc = -EINTR;
240
241 set_current_state(state);
242 if (!pwq->triggered)
243 rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS);
244 __set_current_state(TASK_RUNNING);
245
246 /*
247 * Prepare for the next iteration.
248 *
249 * The following smp_store_mb() serves two purposes. First, it's
250 * the counterpart rmb of the wmb in pollwake() such that data
251 * written before wake up is always visible after wake up.
252 * Second, the full barrier guarantees that triggered clearing
253 * doesn't pass event check of the next iteration. Note that
254 * this problem doesn't exist for the first iteration as
255 * add_wait_queue() has full barrier semantics.
256 */
257 smp_store_mb(pwq->triggered, 0);
258
259 return rc;
260 }
261 EXPORT_SYMBOL(poll_schedule_timeout);
262
263 /**
264 * poll_select_set_timeout - helper function to setup the timeout value
265 * @to: pointer to timespec64 variable for the final timeout
266 * @sec: seconds (from user space)
267 * @nsec: nanoseconds (from user space)
268 *
269 * Note, we do not use a timespec for the user space value here, That
270 * way we can use the function for timeval and compat interfaces as well.
271 *
272 * Returns -EINVAL if sec/nsec are not normalized. Otherwise 0.
273 */
274 int poll_select_set_timeout(struct timespec64 *to, time64_t sec, long nsec)
275 {
276 struct timespec64 ts = {.tv_sec = sec, .tv_nsec = nsec};
277
278 if (!timespec64_valid(&ts))
279 return -EINVAL;
280
281 /* Optimize for the zero timeout value here */
282 if (!sec && !nsec) {
283 to->tv_sec = to->tv_nsec = 0;
284 } else {
285 ktime_get_ts64(to);
286 *to = timespec64_add_safe(*to, ts);
287 }
288 return 0;
289 }
290
291 static int poll_select_copy_remaining(struct timespec64 *end_time,
292 void __user *p,
293 int timeval, int ret)
294 {
295 struct timespec64 rts64;
296 struct timespec rts;
297 struct timeval rtv;
298
299 if (!p)
300 return ret;
301
302 if (current->personality & STICKY_TIMEOUTS)
303 goto sticky;
304
305 /* No update for zero timeout */
306 if (!end_time->tv_sec && !end_time->tv_nsec)
307 return ret;
308
309 ktime_get_ts64(&rts64);
310 rts64 = timespec64_sub(*end_time, rts64);
311 if (rts64.tv_sec < 0)
312 rts64.tv_sec = rts64.tv_nsec = 0;
313
314 rts = timespec64_to_timespec(rts64);
315
316 if (timeval) {
317 if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec))
318 memset(&rtv, 0, sizeof(rtv));
319 rtv.tv_sec = rts64.tv_sec;
320 rtv.tv_usec = rts64.tv_nsec / NSEC_PER_USEC;
321
322 if (!copy_to_user(p, &rtv, sizeof(rtv)))
323 return ret;
324
325 } else if (!copy_to_user(p, &rts, sizeof(rts)))
326 return ret;
327
328 /*
329 * If an application puts its timeval in read-only memory, we
330 * don't want the Linux-specific update to the timeval to
331 * cause a fault after the select has completed
332 * successfully. However, because we're not updating the
333 * timeval, we can't restart the system call.
334 */
335
336 sticky:
337 if (ret == -ERESTARTNOHAND)
338 ret = -EINTR;
339 return ret;
340 }
341
342 /*
343 * Scalable version of the fd_set.
344 */
345
346 typedef struct {
347 unsigned long *in, *out, *ex;
348 unsigned long *res_in, *res_out, *res_ex;
349 } fd_set_bits;
350
351 /*
352 * How many longwords for "nr" bits?
353 */
354 #define FDS_BITPERLONG (8*sizeof(long))
355 #define FDS_LONGS(nr) (((nr)+FDS_BITPERLONG-1)/FDS_BITPERLONG)
356 #define FDS_BYTES(nr) (FDS_LONGS(nr)*sizeof(long))
357
358 /*
359 * We do a VERIFY_WRITE here even though we are only reading this time:
360 * we'll write to it eventually..
361 *
362 * Use "unsigned long" accesses to let user-mode fd_set's be long-aligned.
363 */
364 static inline
365 int get_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
366 {
367 nr = FDS_BYTES(nr);
368 if (ufdset)
369 return copy_from_user(fdset, ufdset, nr) ? -EFAULT : 0;
370
371 memset(fdset, 0, nr);
372 return 0;
373 }
374
375 static inline unsigned long __must_check
376 set_fd_set(unsigned long nr, void __user *ufdset, unsigned long *fdset)
377 {
378 if (ufdset)
379 return __copy_to_user(ufdset, fdset, FDS_BYTES(nr));
380 return 0;
381 }
382
383 static inline
384 void zero_fd_set(unsigned long nr, unsigned long *fdset)
385 {
386 memset(fdset, 0, FDS_BYTES(nr));
387 }
388
389 #define FDS_IN(fds, n) (fds->in + n)
390 #define FDS_OUT(fds, n) (fds->out + n)
391 #define FDS_EX(fds, n) (fds->ex + n)
392
393 #define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n))
394
395 static int max_select_fd(unsigned long n, fd_set_bits *fds)
396 {
397 unsigned long *open_fds;
398 unsigned long set;
399 int max;
400 struct fdtable *fdt;
401
402 /* handle last in-complete long-word first */
403 set = ~(~0UL << (n & (BITS_PER_LONG-1)));
404 n /= BITS_PER_LONG;
405 fdt = files_fdtable(current->files);
406 open_fds = fdt->open_fds + n;
407 max = 0;
408 if (set) {
409 set &= BITS(fds, n);
410 if (set) {
411 if (!(set & ~*open_fds))
412 goto get_max;
413 return -EBADF;
414 }
415 }
416 while (n) {
417 open_fds--;
418 n--;
419 set = BITS(fds, n);
420 if (!set)
421 continue;
422 if (set & ~*open_fds)
423 return -EBADF;
424 if (max)
425 continue;
426 get_max:
427 do {
428 max++;
429 set >>= 1;
430 } while (set);
431 max += n * BITS_PER_LONG;
432 }
433
434 return max;
435 }
436
437 #define POLLIN_SET (POLLRDNORM | POLLRDBAND | POLLIN | POLLHUP | POLLERR)
438 #define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR)
439 #define POLLEX_SET (POLLPRI)
440
441 static inline void wait_key_set(poll_table *wait, unsigned long in,
442 unsigned long out, unsigned long bit,
443 unsigned int ll_flag)
444 {
445 wait->_key = POLLEX_SET | ll_flag;
446 if (in & bit)
447 wait->_key |= POLLIN_SET;
448 if (out & bit)
449 wait->_key |= POLLOUT_SET;
450 }
451
452 static int do_select(int n, fd_set_bits *fds, struct timespec64 *end_time)
453 {
454 ktime_t expire, *to = NULL;
455 struct poll_wqueues table;
456 poll_table *wait;
457 int retval, i, timed_out = 0;
458 u64 slack = 0;
459 unsigned int busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0;
460 unsigned long busy_start = 0;
461
462 rcu_read_lock();
463 retval = max_select_fd(n, fds);
464 rcu_read_unlock();
465
466 if (retval < 0)
467 return retval;
468 n = retval;
469
470 poll_initwait(&table);
471 wait = &table.pt;
472 if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
473 wait->_qproc = NULL;
474 timed_out = 1;
475 }
476
477 if (end_time && !timed_out)
478 slack = select_estimate_accuracy(end_time);
479
480 retval = 0;
481 for (;;) {
482 unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp;
483 bool can_busy_loop = false;
484
485 inp = fds->in; outp = fds->out; exp = fds->ex;
486 rinp = fds->res_in; routp = fds->res_out; rexp = fds->res_ex;
487
488 for (i = 0; i < n; ++rinp, ++routp, ++rexp) {
489 unsigned long in, out, ex, all_bits, bit = 1, mask, j;
490 unsigned long res_in = 0, res_out = 0, res_ex = 0;
491
492 in = *inp++; out = *outp++; ex = *exp++;
493 all_bits = in | out | ex;
494 if (all_bits == 0) {
495 i += BITS_PER_LONG;
496 continue;
497 }
498
499 for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) {
500 struct fd f;
501 if (i >= n)
502 break;
503 if (!(bit & all_bits))
504 continue;
505 f = fdget(i);
506 if (f.file) {
507 const struct file_operations *f_op;
508 f_op = f.file->f_op;
509 mask = DEFAULT_POLLMASK;
510 if (f_op->poll) {
511 wait_key_set(wait, in, out,
512 bit, busy_flag);
513 mask = (*f_op->poll)(f.file, wait);
514 }
515 fdput(f);
516 if ((mask & POLLIN_SET) && (in & bit)) {
517 res_in |= bit;
518 retval++;
519 wait->_qproc = NULL;
520 }
521 if ((mask & POLLOUT_SET) && (out & bit)) {
522 res_out |= bit;
523 retval++;
524 wait->_qproc = NULL;
525 }
526 if ((mask & POLLEX_SET) && (ex & bit)) {
527 res_ex |= bit;
528 retval++;
529 wait->_qproc = NULL;
530 }
531 /* got something, stop busy polling */
532 if (retval) {
533 can_busy_loop = false;
534 busy_flag = 0;
535
536 /*
537 * only remember a returned
538 * POLL_BUSY_LOOP if we asked for it
539 */
540 } else if (busy_flag & mask)
541 can_busy_loop = true;
542
543 }
544 }
545 if (res_in)
546 *rinp = res_in;
547 if (res_out)
548 *routp = res_out;
549 if (res_ex)
550 *rexp = res_ex;
551 cond_resched();
552 }
553 wait->_qproc = NULL;
554 if (retval || timed_out || signal_pending(current))
555 break;
556 if (table.error) {
557 retval = table.error;
558 break;
559 }
560
561 /* only if found POLL_BUSY_LOOP sockets && not out of time */
562 if (can_busy_loop && !need_resched()) {
563 if (!busy_start) {
564 busy_start = busy_loop_current_time();
565 continue;
566 }
567 if (!busy_loop_timeout(busy_start))
568 continue;
569 }
570 busy_flag = 0;
571
572 /*
573 * If this is the first loop and we have a timeout
574 * given, then we convert to ktime_t and set the to
575 * pointer to the expiry value.
576 */
577 if (end_time && !to) {
578 expire = timespec64_to_ktime(*end_time);
579 to = &expire;
580 }
581
582 if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE,
583 to, slack))
584 timed_out = 1;
585 }
586
587 poll_freewait(&table);
588
589 return retval;
590 }
591
592 /*
593 * We can actually return ERESTARTSYS instead of EINTR, but I'd
594 * like to be certain this leads to no problems. So I return
595 * EINTR just for safety.
596 *
597 * Update: ERESTARTSYS breaks at least the xview clock binary, so
598 * I'm trying ERESTARTNOHAND which restart only when you want to.
599 */
600 int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
601 fd_set __user *exp, struct timespec64 *end_time)
602 {
603 fd_set_bits fds;
604 void *bits;
605 int ret, max_fds;
606 size_t size, alloc_size;
607 struct fdtable *fdt;
608 /* Allocate small arguments on the stack to save memory and be faster */
609 long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
610
611 ret = -EINVAL;
612 if (n < 0)
613 goto out_nofds;
614
615 /* max_fds can increase, so grab it once to avoid race */
616 rcu_read_lock();
617 fdt = files_fdtable(current->files);
618 max_fds = fdt->max_fds;
619 rcu_read_unlock();
620 if (n > max_fds)
621 n = max_fds;
622
623 /*
624 * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
625 * since we used fdset we need to allocate memory in units of
626 * long-words.
627 */
628 size = FDS_BYTES(n);
629 bits = stack_fds;
630 if (size > sizeof(stack_fds) / 6) {
631 /* Not enough space in on-stack array; must use kmalloc */
632 ret = -ENOMEM;
633 if (size > (SIZE_MAX / 6))
634 goto out_nofds;
635
636 alloc_size = 6 * size;
637 bits = kvmalloc(alloc_size, GFP_KERNEL);
638 if (!bits)
639 goto out_nofds;
640 }
641 fds.in = bits;
642 fds.out = bits + size;
643 fds.ex = bits + 2*size;
644 fds.res_in = bits + 3*size;
645 fds.res_out = bits + 4*size;
646 fds.res_ex = bits + 5*size;
647
648 if ((ret = get_fd_set(n, inp, fds.in)) ||
649 (ret = get_fd_set(n, outp, fds.out)) ||
650 (ret = get_fd_set(n, exp, fds.ex)))
651 goto out;
652 zero_fd_set(n, fds.res_in);
653 zero_fd_set(n, fds.res_out);
654 zero_fd_set(n, fds.res_ex);
655
656 ret = do_select(n, &fds, end_time);
657
658 if (ret < 0)
659 goto out;
660 if (!ret) {
661 ret = -ERESTARTNOHAND;
662 if (signal_pending(current))
663 goto out;
664 ret = 0;
665 }
666
667 if (set_fd_set(n, inp, fds.res_in) ||
668 set_fd_set(n, outp, fds.res_out) ||
669 set_fd_set(n, exp, fds.res_ex))
670 ret = -EFAULT;
671
672 out:
673 if (bits != stack_fds)
674 kvfree(bits);
675 out_nofds:
676 return ret;
677 }
678
679 SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp,
680 fd_set __user *, exp, struct timeval __user *, tvp)
681 {
682 struct timespec64 end_time, *to = NULL;
683 struct timeval tv;
684 int ret;
685
686 if (tvp) {
687 if (copy_from_user(&tv, tvp, sizeof(tv)))
688 return -EFAULT;
689
690 to = &end_time;
691 if (poll_select_set_timeout(to,
692 tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
693 (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
694 return -EINVAL;
695 }
696
697 ret = core_sys_select(n, inp, outp, exp, to);
698 ret = poll_select_copy_remaining(&end_time, tvp, 1, ret);
699
700 return ret;
701 }
702
703 static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp,
704 fd_set __user *exp, struct timespec __user *tsp,
705 const sigset_t __user *sigmask, size_t sigsetsize)
706 {
707 sigset_t ksigmask, sigsaved;
708 struct timespec ts;
709 struct timespec64 ts64, end_time, *to = NULL;
710 int ret;
711
712 if (tsp) {
713 if (copy_from_user(&ts, tsp, sizeof(ts)))
714 return -EFAULT;
715 ts64 = timespec_to_timespec64(ts);
716
717 to = &end_time;
718 if (poll_select_set_timeout(to, ts64.tv_sec, ts64.tv_nsec))
719 return -EINVAL;
720 }
721
722 if (sigmask) {
723 /* XXX: Don't preclude handling different sized sigset_t's. */
724 if (sigsetsize != sizeof(sigset_t))
725 return -EINVAL;
726 if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask)))
727 return -EFAULT;
728
729 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
730 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
731 }
732
733 ret = core_sys_select(n, inp, outp, exp, to);
734 ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
735
736 if (ret == -ERESTARTNOHAND) {
737 /*
738 * Don't restore the signal mask yet. Let do_signal() deliver
739 * the signal on the way back to userspace, before the signal
740 * mask is restored.
741 */
742 if (sigmask) {
743 memcpy(&current->saved_sigmask, &sigsaved,
744 sizeof(sigsaved));
745 set_restore_sigmask();
746 }
747 } else if (sigmask)
748 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
749
750 return ret;
751 }
752
753 /*
754 * Most architectures can't handle 7-argument syscalls. So we provide a
755 * 6-argument version where the sixth argument is a pointer to a structure
756 * which has a pointer to the sigset_t itself followed by a size_t containing
757 * the sigset size.
758 */
759 SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp,
760 fd_set __user *, exp, struct timespec __user *, tsp,
761 void __user *, sig)
762 {
763 size_t sigsetsize = 0;
764 sigset_t __user *up = NULL;
765
766 if (sig) {
767 if (!access_ok(VERIFY_READ, sig, sizeof(void *)+sizeof(size_t))
768 || __get_user(up, (sigset_t __user * __user *)sig)
769 || __get_user(sigsetsize,
770 (size_t __user *)(sig+sizeof(void *))))
771 return -EFAULT;
772 }
773
774 return do_pselect(n, inp, outp, exp, tsp, up, sigsetsize);
775 }
776
777 #ifdef __ARCH_WANT_SYS_OLD_SELECT
778 struct sel_arg_struct {
779 unsigned long n;
780 fd_set __user *inp, *outp, *exp;
781 struct timeval __user *tvp;
782 };
783
784 SYSCALL_DEFINE1(old_select, struct sel_arg_struct __user *, arg)
785 {
786 struct sel_arg_struct a;
787
788 if (copy_from_user(&a, arg, sizeof(a)))
789 return -EFAULT;
790 return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
791 }
792 #endif
793
794 struct poll_list {
795 struct poll_list *next;
796 int len;
797 struct pollfd entries[0];
798 };
799
800 #define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))
801
802 /*
803 * Fish for pollable events on the pollfd->fd file descriptor. We're only
804 * interested in events matching the pollfd->events mask, and the result
805 * matching that mask is both recorded in pollfd->revents and returned. The
806 * pwait poll_table will be used by the fd-provided poll handler for waiting,
807 * if pwait->_qproc is non-NULL.
808 */
809 static inline unsigned int do_pollfd(struct pollfd *pollfd, poll_table *pwait,
810 bool *can_busy_poll,
811 unsigned int busy_flag)
812 {
813 unsigned int mask;
814 int fd;
815
816 mask = 0;
817 fd = pollfd->fd;
818 if (fd >= 0) {
819 struct fd f = fdget(fd);
820 mask = POLLNVAL;
821 if (f.file) {
822 mask = DEFAULT_POLLMASK;
823 if (f.file->f_op->poll) {
824 pwait->_key = pollfd->events|POLLERR|POLLHUP;
825 pwait->_key |= busy_flag;
826 mask = f.file->f_op->poll(f.file, pwait);
827 if (mask & busy_flag)
828 *can_busy_poll = true;
829 }
830 /* Mask out unneeded events. */
831 mask &= pollfd->events | POLLERR | POLLHUP;
832 fdput(f);
833 }
834 }
835 pollfd->revents = mask;
836
837 return mask;
838 }
839
840 static int do_poll(struct poll_list *list, struct poll_wqueues *wait,
841 struct timespec64 *end_time)
842 {
843 poll_table* pt = &wait->pt;
844 ktime_t expire, *to = NULL;
845 int timed_out = 0, count = 0;
846 u64 slack = 0;
847 unsigned int busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0;
848 unsigned long busy_start = 0;
849
850 /* Optimise the no-wait case */
851 if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
852 pt->_qproc = NULL;
853 timed_out = 1;
854 }
855
856 if (end_time && !timed_out)
857 slack = select_estimate_accuracy(end_time);
858
859 for (;;) {
860 struct poll_list *walk;
861 bool can_busy_loop = false;
862
863 for (walk = list; walk != NULL; walk = walk->next) {
864 struct pollfd * pfd, * pfd_end;
865
866 pfd = walk->entries;
867 pfd_end = pfd + walk->len;
868 for (; pfd != pfd_end; pfd++) {
869 /*
870 * Fish for events. If we found one, record it
871 * and kill poll_table->_qproc, so we don't
872 * needlessly register any other waiters after
873 * this. They'll get immediately deregistered
874 * when we break out and return.
875 */
876 if (do_pollfd(pfd, pt, &can_busy_loop,
877 busy_flag)) {
878 count++;
879 pt->_qproc = NULL;
880 /* found something, stop busy polling */
881 busy_flag = 0;
882 can_busy_loop = false;
883 }
884 }
885 }
886 /*
887 * All waiters have already been registered, so don't provide
888 * a poll_table->_qproc to them on the next loop iteration.
889 */
890 pt->_qproc = NULL;
891 if (!count) {
892 count = wait->error;
893 if (signal_pending(current))
894 count = -EINTR;
895 }
896 if (count || timed_out)
897 break;
898
899 /* only if found POLL_BUSY_LOOP sockets && not out of time */
900 if (can_busy_loop && !need_resched()) {
901 if (!busy_start) {
902 busy_start = busy_loop_current_time();
903 continue;
904 }
905 if (!busy_loop_timeout(busy_start))
906 continue;
907 }
908 busy_flag = 0;
909
910 /*
911 * If this is the first loop and we have a timeout
912 * given, then we convert to ktime_t and set the to
913 * pointer to the expiry value.
914 */
915 if (end_time && !to) {
916 expire = timespec64_to_ktime(*end_time);
917 to = &expire;
918 }
919
920 if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack))
921 timed_out = 1;
922 }
923 return count;
924 }
925
926 #define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \
927 sizeof(struct pollfd))
928
929 static int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds,
930 struct timespec64 *end_time)
931 {
932 struct poll_wqueues table;
933 int err = -EFAULT, fdcount, len, size;
934 /* Allocate small arguments on the stack to save memory and be
935 faster - use long to make sure the buffer is aligned properly
936 on 64 bit archs to avoid unaligned access */
937 long stack_pps[POLL_STACK_ALLOC/sizeof(long)];
938 struct poll_list *const head = (struct poll_list *)stack_pps;
939 struct poll_list *walk = head;
940 unsigned long todo = nfds;
941
942 if (nfds > rlimit(RLIMIT_NOFILE))
943 return -EINVAL;
944
945 len = min_t(unsigned int, nfds, N_STACK_PPS);
946 for (;;) {
947 walk->next = NULL;
948 walk->len = len;
949 if (!len)
950 break;
951
952 if (copy_from_user(walk->entries, ufds + nfds-todo,
953 sizeof(struct pollfd) * walk->len))
954 goto out_fds;
955
956 todo -= walk->len;
957 if (!todo)
958 break;
959
960 len = min(todo, POLLFD_PER_PAGE);
961 size = sizeof(struct poll_list) + sizeof(struct pollfd) * len;
962 walk = walk->next = kmalloc(size, GFP_KERNEL);
963 if (!walk) {
964 err = -ENOMEM;
965 goto out_fds;
966 }
967 }
968
969 poll_initwait(&table);
970 fdcount = do_poll(head, &table, end_time);
971 poll_freewait(&table);
972
973 for (walk = head; walk; walk = walk->next) {
974 struct pollfd *fds = walk->entries;
975 int j;
976
977 for (j = 0; j < walk->len; j++, ufds++)
978 if (__put_user(fds[j].revents, &ufds->revents))
979 goto out_fds;
980 }
981
982 err = fdcount;
983 out_fds:
984 walk = head->next;
985 while (walk) {
986 struct poll_list *pos = walk;
987 walk = walk->next;
988 kfree(pos);
989 }
990
991 return err;
992 }
993
994 static long do_restart_poll(struct restart_block *restart_block)
995 {
996 struct pollfd __user *ufds = restart_block->poll.ufds;
997 int nfds = restart_block->poll.nfds;
998 struct timespec64 *to = NULL, end_time;
999 int ret;
1000
1001 if (restart_block->poll.has_timeout) {
1002 end_time.tv_sec = restart_block->poll.tv_sec;
1003 end_time.tv_nsec = restart_block->poll.tv_nsec;
1004 to = &end_time;
1005 }
1006
1007 ret = do_sys_poll(ufds, nfds, to);
1008
1009 if (ret == -EINTR) {
1010 restart_block->fn = do_restart_poll;
1011 ret = -ERESTART_RESTARTBLOCK;
1012 }
1013 return ret;
1014 }
1015
1016 SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
1017 int, timeout_msecs)
1018 {
1019 struct timespec64 end_time, *to = NULL;
1020 int ret;
1021
1022 if (timeout_msecs >= 0) {
1023 to = &end_time;
1024 poll_select_set_timeout(to, timeout_msecs / MSEC_PER_SEC,
1025 NSEC_PER_MSEC * (timeout_msecs % MSEC_PER_SEC));
1026 }
1027
1028 ret = do_sys_poll(ufds, nfds, to);
1029
1030 if (ret == -EINTR) {
1031 struct restart_block *restart_block;
1032
1033 restart_block = &current->restart_block;
1034 restart_block->fn = do_restart_poll;
1035 restart_block->poll.ufds = ufds;
1036 restart_block->poll.nfds = nfds;
1037
1038 if (timeout_msecs >= 0) {
1039 restart_block->poll.tv_sec = end_time.tv_sec;
1040 restart_block->poll.tv_nsec = end_time.tv_nsec;
1041 restart_block->poll.has_timeout = 1;
1042 } else
1043 restart_block->poll.has_timeout = 0;
1044
1045 ret = -ERESTART_RESTARTBLOCK;
1046 }
1047 return ret;
1048 }
1049
1050 SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
1051 struct timespec __user *, tsp, const sigset_t __user *, sigmask,
1052 size_t, sigsetsize)
1053 {
1054 sigset_t ksigmask, sigsaved;
1055 struct timespec ts;
1056 struct timespec64 end_time, *to = NULL;
1057 int ret;
1058
1059 if (tsp) {
1060 if (copy_from_user(&ts, tsp, sizeof(ts)))
1061 return -EFAULT;
1062
1063 to = &end_time;
1064 if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
1065 return -EINVAL;
1066 }
1067
1068 if (sigmask) {
1069 /* XXX: Don't preclude handling different sized sigset_t's. */
1070 if (sigsetsize != sizeof(sigset_t))
1071 return -EINVAL;
1072 if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask)))
1073 return -EFAULT;
1074
1075 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
1076 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1077 }
1078
1079 ret = do_sys_poll(ufds, nfds, to);
1080
1081 /* We can restart this syscall, usually */
1082 if (ret == -EINTR) {
1083 /*
1084 * Don't restore the signal mask yet. Let do_signal() deliver
1085 * the signal on the way back to userspace, before the signal
1086 * mask is restored.
1087 */
1088 if (sigmask) {
1089 memcpy(&current->saved_sigmask, &sigsaved,
1090 sizeof(sigsaved));
1091 set_restore_sigmask();
1092 }
1093 ret = -ERESTARTNOHAND;
1094 } else if (sigmask)
1095 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1096
1097 ret = poll_select_copy_remaining(&end_time, tsp, 0, ret);
1098
1099 return ret;
1100 }
1101
1102 #ifdef CONFIG_COMPAT
1103 #define __COMPAT_NFDBITS (8 * sizeof(compat_ulong_t))
1104
1105 static
1106 int compat_poll_select_copy_remaining(struct timespec *end_time, void __user *p,
1107 int timeval, int ret)
1108 {
1109 struct timespec ts;
1110
1111 if (!p)
1112 return ret;
1113
1114 if (current->personality & STICKY_TIMEOUTS)
1115 goto sticky;
1116
1117 /* No update for zero timeout */
1118 if (!end_time->tv_sec && !end_time->tv_nsec)
1119 return ret;
1120
1121 ktime_get_ts(&ts);
1122 ts = timespec_sub(*end_time, ts);
1123 if (ts.tv_sec < 0)
1124 ts.tv_sec = ts.tv_nsec = 0;
1125
1126 if (timeval) {
1127 struct compat_timeval rtv;
1128
1129 rtv.tv_sec = ts.tv_sec;
1130 rtv.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
1131
1132 if (!copy_to_user(p, &rtv, sizeof(rtv)))
1133 return ret;
1134 } else {
1135 struct compat_timespec rts;
1136
1137 rts.tv_sec = ts.tv_sec;
1138 rts.tv_nsec = ts.tv_nsec;
1139
1140 if (!copy_to_user(p, &rts, sizeof(rts)))
1141 return ret;
1142 }
1143 /*
1144 * If an application puts its timeval in read-only memory, we
1145 * don't want the Linux-specific update to the timeval to
1146 * cause a fault after the select has completed
1147 * successfully. However, because we're not updating the
1148 * timeval, we can't restart the system call.
1149 */
1150
1151 sticky:
1152 if (ret == -ERESTARTNOHAND)
1153 ret = -EINTR;
1154 return ret;
1155 }
1156
1157 /*
1158 * Ooo, nasty. We need here to frob 32-bit unsigned longs to
1159 * 64-bit unsigned longs.
1160 */
1161 static
1162 int compat_get_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
1163 unsigned long *fdset)
1164 {
1165 if (ufdset) {
1166 return compat_get_bitmap(fdset, ufdset, nr);
1167 } else {
1168 zero_fd_set(nr, fdset);
1169 return 0;
1170 }
1171 }
1172
1173 static
1174 int compat_set_fd_set(unsigned long nr, compat_ulong_t __user *ufdset,
1175 unsigned long *fdset)
1176 {
1177 if (!ufdset)
1178 return 0;
1179 return compat_put_bitmap(ufdset, fdset, nr);
1180 }
1181
1182
1183 /*
1184 * This is a virtual copy of sys_select from fs/select.c and probably
1185 * should be compared to it from time to time
1186 */
1187
1188 /*
1189 * We can actually return ERESTARTSYS instead of EINTR, but I'd
1190 * like to be certain this leads to no problems. So I return
1191 * EINTR just for safety.
1192 *
1193 * Update: ERESTARTSYS breaks at least the xview clock binary, so
1194 * I'm trying ERESTARTNOHAND which restart only when you want to.
1195 */
1196 static int compat_core_sys_select(int n, compat_ulong_t __user *inp,
1197 compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1198 struct timespec *end_time)
1199 {
1200 fd_set_bits fds;
1201 void *bits;
1202 int size, max_fds, ret = -EINVAL;
1203 struct fdtable *fdt;
1204 long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
1205
1206 if (n < 0)
1207 goto out_nofds;
1208
1209 /* max_fds can increase, so grab it once to avoid race */
1210 rcu_read_lock();
1211 fdt = files_fdtable(current->files);
1212 max_fds = fdt->max_fds;
1213 rcu_read_unlock();
1214 if (n > max_fds)
1215 n = max_fds;
1216
1217 /*
1218 * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
1219 * since we used fdset we need to allocate memory in units of
1220 * long-words.
1221 */
1222 size = FDS_BYTES(n);
1223 bits = stack_fds;
1224 if (size > sizeof(stack_fds) / 6) {
1225 bits = kmalloc(6 * size, GFP_KERNEL);
1226 ret = -ENOMEM;
1227 if (!bits)
1228 goto out_nofds;
1229 }
1230 fds.in = (unsigned long *) bits;
1231 fds.out = (unsigned long *) (bits + size);
1232 fds.ex = (unsigned long *) (bits + 2*size);
1233 fds.res_in = (unsigned long *) (bits + 3*size);
1234 fds.res_out = (unsigned long *) (bits + 4*size);
1235 fds.res_ex = (unsigned long *) (bits + 5*size);
1236
1237 if ((ret = compat_get_fd_set(n, inp, fds.in)) ||
1238 (ret = compat_get_fd_set(n, outp, fds.out)) ||
1239 (ret = compat_get_fd_set(n, exp, fds.ex)))
1240 goto out;
1241 zero_fd_set(n, fds.res_in);
1242 zero_fd_set(n, fds.res_out);
1243 zero_fd_set(n, fds.res_ex);
1244
1245 ret = do_select(n, &fds, end_time);
1246
1247 if (ret < 0)
1248 goto out;
1249 if (!ret) {
1250 ret = -ERESTARTNOHAND;
1251 if (signal_pending(current))
1252 goto out;
1253 ret = 0;
1254 }
1255
1256 if (compat_set_fd_set(n, inp, fds.res_in) ||
1257 compat_set_fd_set(n, outp, fds.res_out) ||
1258 compat_set_fd_set(n, exp, fds.res_ex))
1259 ret = -EFAULT;
1260 out:
1261 if (bits != stack_fds)
1262 kfree(bits);
1263 out_nofds:
1264 return ret;
1265 }
1266
1267 COMPAT_SYSCALL_DEFINE5(select, int, n, compat_ulong_t __user *, inp,
1268 compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
1269 struct compat_timeval __user *, tvp)
1270 {
1271 struct timespec end_time, *to = NULL;
1272 struct compat_timeval tv;
1273 int ret;
1274
1275 if (tvp) {
1276 if (copy_from_user(&tv, tvp, sizeof(tv)))
1277 return -EFAULT;
1278
1279 to = &end_time;
1280 if (poll_select_set_timeout(to,
1281 tv.tv_sec + (tv.tv_usec / USEC_PER_SEC),
1282 (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC))
1283 return -EINVAL;
1284 }
1285
1286 ret = compat_core_sys_select(n, inp, outp, exp, to);
1287 ret = compat_poll_select_copy_remaining(&end_time, tvp, 1, ret);
1288
1289 return ret;
1290 }
1291
1292 struct compat_sel_arg_struct {
1293 compat_ulong_t n;
1294 compat_uptr_t inp;
1295 compat_uptr_t outp;
1296 compat_uptr_t exp;
1297 compat_uptr_t tvp;
1298 };
1299
1300 COMPAT_SYSCALL_DEFINE1(old_select, struct compat_sel_arg_struct __user *, arg)
1301 {
1302 struct compat_sel_arg_struct a;
1303
1304 if (copy_from_user(&a, arg, sizeof(a)))
1305 return -EFAULT;
1306 return compat_sys_select(a.n, compat_ptr(a.inp), compat_ptr(a.outp),
1307 compat_ptr(a.exp), compat_ptr(a.tvp));
1308 }
1309
1310 static long do_compat_pselect(int n, compat_ulong_t __user *inp,
1311 compat_ulong_t __user *outp, compat_ulong_t __user *exp,
1312 struct compat_timespec __user *tsp, compat_sigset_t __user *sigmask,
1313 compat_size_t sigsetsize)
1314 {
1315 compat_sigset_t ss32;
1316 sigset_t ksigmask, sigsaved;
1317 struct compat_timespec ts;
1318 struct timespec end_time, *to = NULL;
1319 int ret;
1320
1321 if (tsp) {
1322 if (copy_from_user(&ts, tsp, sizeof(ts)))
1323 return -EFAULT;
1324
1325 to = &end_time;
1326 if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
1327 return -EINVAL;
1328 }
1329
1330 if (sigmask) {
1331 if (sigsetsize != sizeof(compat_sigset_t))
1332 return -EINVAL;
1333 if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
1334 return -EFAULT;
1335 sigset_from_compat(&ksigmask, &ss32);
1336
1337 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
1338 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1339 }
1340
1341 ret = compat_core_sys_select(n, inp, outp, exp, to);
1342 ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret);
1343
1344 if (ret == -ERESTARTNOHAND) {
1345 /*
1346 * Don't restore the signal mask yet. Let do_signal() deliver
1347 * the signal on the way back to userspace, before the signal
1348 * mask is restored.
1349 */
1350 if (sigmask) {
1351 memcpy(&current->saved_sigmask, &sigsaved,
1352 sizeof(sigsaved));
1353 set_restore_sigmask();
1354 }
1355 } else if (sigmask)
1356 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1357
1358 return ret;
1359 }
1360
1361 COMPAT_SYSCALL_DEFINE6(pselect6, int, n, compat_ulong_t __user *, inp,
1362 compat_ulong_t __user *, outp, compat_ulong_t __user *, exp,
1363 struct compat_timespec __user *, tsp, void __user *, sig)
1364 {
1365 compat_size_t sigsetsize = 0;
1366 compat_uptr_t up = 0;
1367
1368 if (sig) {
1369 if (!access_ok(VERIFY_READ, sig,
1370 sizeof(compat_uptr_t)+sizeof(compat_size_t)) ||
1371 __get_user(up, (compat_uptr_t __user *)sig) ||
1372 __get_user(sigsetsize,
1373 (compat_size_t __user *)(sig+sizeof(up))))
1374 return -EFAULT;
1375 }
1376 return do_compat_pselect(n, inp, outp, exp, tsp, compat_ptr(up),
1377 sigsetsize);
1378 }
1379
1380 COMPAT_SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds,
1381 unsigned int, nfds, struct compat_timespec __user *, tsp,
1382 const compat_sigset_t __user *, sigmask, compat_size_t, sigsetsize)
1383 {
1384 compat_sigset_t ss32;
1385 sigset_t ksigmask, sigsaved;
1386 struct compat_timespec ts;
1387 struct timespec end_time, *to = NULL;
1388 int ret;
1389
1390 if (tsp) {
1391 if (copy_from_user(&ts, tsp, sizeof(ts)))
1392 return -EFAULT;
1393
1394 to = &end_time;
1395 if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec))
1396 return -EINVAL;
1397 }
1398
1399 if (sigmask) {
1400 if (sigsetsize != sizeof(compat_sigset_t))
1401 return -EINVAL;
1402 if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
1403 return -EFAULT;
1404 sigset_from_compat(&ksigmask, &ss32);
1405
1406 sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP));
1407 sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
1408 }
1409
1410 ret = do_sys_poll(ufds, nfds, to);
1411
1412 /* We can restart this syscall, usually */
1413 if (ret == -EINTR) {
1414 /*
1415 * Don't restore the signal mask yet. Let do_signal() deliver
1416 * the signal on the way back to userspace, before the signal
1417 * mask is restored.
1418 */
1419 if (sigmask) {
1420 memcpy(&current->saved_sigmask, &sigsaved,
1421 sizeof(sigsaved));
1422 set_restore_sigmask();
1423 }
1424 ret = -ERESTARTNOHAND;
1425 } else if (sigmask)
1426 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
1427
1428 ret = compat_poll_select_copy_remaining(&end_time, tsp, 0, ret);
1429
1430 return ret;
1431 }
1432 #endif
Linux with added FPC-III support