1 /* Modified by Broadcom Corp. Portions Copyright (c) Broadcom Corp, 2012. */
3 * This file contains the procedures for the handling of select and poll
5 * Created for Linux based loosely upon Mathius Lattner's minix
6 * patches by Peter MacDonald. Heavily edited by Linus.
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.
14 * Changed sys_poll()/do_poll() to use PAGE_SIZE chunk-based allocation
15 * of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian).
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/syscalls.h>
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/poll.h>
24 #include <linux/personality.h> /* for STICKY_TIMEOUTS */
25 #include <linux/file.h>
26 #include <linux/fdtable.h>
28 #include <linux/rcupdate.h>
29 #include <linux/hrtimer.h>
31 #include <asm/uaccess.h>
37 * Estimate expected accuracy in ns from a timeval.
39 * After quite a bit of churning around, we've settled on
40 * a simple thing of taking 0.1% of the timeout as the
41 * slack, with a cap of 100 msec.
42 * "nice" tasks get a 0.5% slack instead.
44 * Consider this comment an open invitation to come up with even
48 #define MAX_SLACK (100 * NSEC_PER_MSEC)
50 static long __estimate_accuracy(struct timespec
*tv
)
58 if (task_nice(current
) > 0)
59 divfactor
= divfactor
/ 5;
61 if (tv
->tv_sec
> MAX_SLACK
/ (NSEC_PER_SEC
/divfactor
))
64 slack
= tv
->tv_nsec
/ divfactor
;
65 slack
+= tv
->tv_sec
* (NSEC_PER_SEC
/divfactor
);
67 if (slack
> MAX_SLACK
)
73 static long estimate_accuracy(struct timespec
*tv
)
79 * Realtime tasks get a slack of 0 for obvious reasons.
86 now
= timespec_sub(*tv
, now
);
87 ret
= __estimate_accuracy(&now
);
88 if (ret
< current
->timer_slack_ns
)
89 return current
->timer_slack_ns
;
95 struct poll_table_page
{
96 struct poll_table_page
* next
;
97 struct poll_table_entry
* entry
;
98 struct poll_table_entry entries
[0];
101 #define POLL_TABLE_FULL(table) \
102 ((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table))
105 * Ok, Peter made a complicated, but straightforward multiple_wait() function.
106 * I have rewritten this, taking some shortcuts: This code may not be easy to
107 * follow, but it should be free of race-conditions, and it's practical. If you
108 * understand what I'm doing here, then you understand how the linux
109 * sleep/wakeup mechanism works.
111 * Two very simple procedures, poll_wait() and poll_freewait() make all the
112 * work. poll_wait() is an inline-function defined in <linux/poll.h>,
113 * as all select/poll functions have to call it to add an entry to the
116 static void __pollwait(struct file
*filp
, wait_queue_head_t
*wait_address
,
119 void poll_initwait(struct poll_wqueues
*pwq
)
121 init_poll_funcptr(&pwq
->pt
, __pollwait
);
122 pwq
->polling_task
= current
;
126 pwq
->inline_index
= 0;
128 EXPORT_SYMBOL(poll_initwait
);
130 static void free_poll_entry(struct poll_table_entry
*entry
)
132 remove_wait_queue(entry
->wait_address
, &entry
->wait
);
136 void poll_freewait(struct poll_wqueues
*pwq
)
138 struct poll_table_page
* p
= pwq
->table
;
140 for (i
= 0; i
< pwq
->inline_index
; i
++)
141 free_poll_entry(pwq
->inline_entries
+ i
);
143 struct poll_table_entry
* entry
;
144 struct poll_table_page
*old
;
149 free_poll_entry(entry
);
150 } while (entry
> p
->entries
);
153 free_page((unsigned long) old
);
156 EXPORT_SYMBOL(poll_freewait
);
158 static struct poll_table_entry
*poll_get_entry(struct poll_wqueues
*p
)
160 struct poll_table_page
*table
= p
->table
;
162 if (p
->inline_index
< N_INLINE_POLL_ENTRIES
)
163 return p
->inline_entries
+ p
->inline_index
++;
165 if (!table
|| POLL_TABLE_FULL(table
)) {
166 struct poll_table_page
*new_table
;
168 new_table
= (struct poll_table_page
*) __get_free_page(GFP_KERNEL
);
173 new_table
->entry
= new_table
->entries
;
174 new_table
->next
= table
;
175 p
->table
= new_table
;
179 return table
->entry
++;
182 static int __pollwake(wait_queue_t
*wait
, unsigned mode
, int sync
, void *key
)
184 struct poll_wqueues
*pwq
= wait
->private;
185 DECLARE_WAITQUEUE(dummy_wait
, pwq
->polling_task
);
188 * Although this function is called under waitqueue lock, LOCK
189 * doesn't imply write barrier and the users expect write
190 * barrier semantics on wakeup functions. The following
191 * smp_wmb() is equivalent to smp_wmb() in try_to_wake_up()
192 * and is paired with set_mb() in poll_schedule_timeout.
198 * Perform the default wake up operation using a dummy
201 * TODO: This is hacky but there currently is no interface to
202 * pass in @sync. @sync is scheduled to be removed and once
203 * that happens, wake_up_process() can be used directly.
205 return default_wake_function(&dummy_wait
, mode
, sync
, key
);
208 static int pollwake(wait_queue_t
*wait
, unsigned mode
, int sync
, void *key
)
210 struct poll_table_entry
*entry
;
212 entry
= container_of(wait
, struct poll_table_entry
, wait
);
213 if (key
&& !((unsigned long)key
& entry
->key
))
215 return __pollwake(wait
, mode
, sync
, key
);
218 /* Add a new entry */
219 static void __pollwait(struct file
*filp
, wait_queue_head_t
*wait_address
,
222 struct poll_wqueues
*pwq
= container_of(p
, struct poll_wqueues
, pt
);
223 struct poll_table_entry
*entry
= poll_get_entry(pwq
);
228 entry
->wait_address
= wait_address
;
230 init_waitqueue_func_entry(&entry
->wait
, pollwake
);
231 entry
->wait
.private = pwq
;
232 add_wait_queue(wait_address
, &entry
->wait
);
235 int poll_schedule_timeout(struct poll_wqueues
*pwq
, int state
,
236 ktime_t
*expires
, unsigned long slack
)
240 set_current_state(state
);
242 rc
= schedule_hrtimeout_range(expires
, slack
, HRTIMER_MODE_ABS
);
243 __set_current_state(TASK_RUNNING
);
246 * Prepare for the next iteration.
248 * The following set_mb() serves two purposes. First, it's
249 * the counterpart rmb of the wmb in pollwake() such that data
250 * written before wake up is always visible after wake up.
251 * Second, the full barrier guarantees that triggered clearing
252 * doesn't pass event check of the next iteration. Note that
253 * this problem doesn't exist for the first iteration as
254 * add_wait_queue() has full barrier semantics.
256 set_mb(pwq
->triggered
, 0);
260 EXPORT_SYMBOL(poll_schedule_timeout
);
263 * poll_select_set_timeout - helper function to setup the timeout value
264 * @to: pointer to timespec variable for the final timeout
265 * @sec: seconds (from user space)
266 * @nsec: nanoseconds (from user space)
268 * Note, we do not use a timespec for the user space value here, That
269 * way we can use the function for timeval and compat interfaces as well.
271 * Returns -EINVAL if sec/nsec are not normalized. Otherwise 0.
273 int poll_select_set_timeout(struct timespec
*to
, long sec
, long nsec
)
275 struct timespec ts
= {.tv_sec
= sec
, .tv_nsec
= nsec
};
277 if (!timespec_valid(&ts
))
280 /* Optimize for the zero timeout value here */
282 to
->tv_sec
= to
->tv_nsec
= 0;
285 *to
= timespec_add_safe(*to
, ts
);
290 static int poll_select_copy_remaining(struct timespec
*end_time
, void __user
*p
,
291 int timeval
, int ret
)
299 if (current
->personality
& STICKY_TIMEOUTS
)
302 /* No update for zero timeout */
303 if (!end_time
->tv_sec
&& !end_time
->tv_nsec
)
307 rts
= timespec_sub(*end_time
, rts
);
309 rts
.tv_sec
= rts
.tv_nsec
= 0;
312 rtv
.tv_sec
= rts
.tv_sec
;
313 rtv
.tv_usec
= rts
.tv_nsec
/ NSEC_PER_USEC
;
315 if (!copy_to_user(p
, &rtv
, sizeof(rtv
)))
318 } else if (!copy_to_user(p
, &rts
, sizeof(rts
)))
322 * If an application puts its timeval in read-only memory, we
323 * don't want the Linux-specific update to the timeval to
324 * cause a fault after the select has completed
325 * successfully. However, because we're not updating the
326 * timeval, we can't restart the system call.
330 if (ret
== -ERESTARTNOHAND
)
335 #define FDS_IN(fds, n) (fds->in + n)
336 #define FDS_OUT(fds, n) (fds->out + n)
337 #define FDS_EX(fds, n) (fds->ex + n)
339 #define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n))
341 static int max_select_fd(unsigned long n
, fd_set_bits
*fds
)
343 unsigned long *open_fds
;
348 /* handle last in-complete long-word first */
349 set
= ~(~0UL << (n
& (__NFDBITS
-1)));
351 fdt
= files_fdtable(current
->files
);
352 open_fds
= fdt
->open_fds
->fds_bits
+n
;
357 if (!(set
& ~*open_fds
))
368 if (set
& ~*open_fds
)
377 max
+= n
* __NFDBITS
;
383 #define POLLIN_SET (POLLRDNORM | POLLRDBAND | POLLIN | POLLHUP | POLLERR)
384 #define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR)
385 #define POLLEX_SET (POLLPRI)
387 static inline void wait_key_set(poll_table
*wait
, unsigned long in
,
388 unsigned long out
, unsigned long bit
)
391 wait
->key
= POLLEX_SET
;
393 wait
->key
|= POLLIN_SET
;
395 wait
->key
|= POLLOUT_SET
;
399 int BCMFASTPATH_HOST
do_select(int n
, fd_set_bits
*fds
, struct timespec
*end_time
)
401 ktime_t expire
, *to
= NULL
;
402 struct poll_wqueues table
;
404 int retval
, i
, timed_out
= 0;
405 unsigned long slack
= 0;
408 retval
= max_select_fd(n
, fds
);
415 poll_initwait(&table
);
417 if (end_time
&& !end_time
->tv_sec
&& !end_time
->tv_nsec
) {
422 if (end_time
&& !timed_out
)
423 slack
= estimate_accuracy(end_time
);
427 unsigned long *rinp
, *routp
, *rexp
, *inp
, *outp
, *exp
;
429 inp
= fds
->in
; outp
= fds
->out
; exp
= fds
->ex
;
430 rinp
= fds
->res_in
; routp
= fds
->res_out
; rexp
= fds
->res_ex
;
432 for (i
= 0; i
< n
; ++rinp
, ++routp
, ++rexp
) {
433 unsigned long in
, out
, ex
, all_bits
, bit
= 1, mask
, j
;
434 unsigned long res_in
= 0, res_out
= 0, res_ex
= 0;
435 const struct file_operations
*f_op
= NULL
;
436 struct file
*file
= NULL
;
438 in
= *inp
++; out
= *outp
++; ex
= *exp
++;
439 all_bits
= in
| out
| ex
;
445 for (j
= 0; j
< __NFDBITS
; ++j
, ++i
, bit
<<= 1) {
449 if (!(bit
& all_bits
))
451 file
= fget_light(i
, &fput_needed
);
454 mask
= DEFAULT_POLLMASK
;
455 if (f_op
&& f_op
->poll
) {
456 wait_key_set(wait
, in
, out
, bit
);
457 mask
= (*f_op
->poll
)(file
, wait
);
459 fput_light(file
, fput_needed
);
460 if ((mask
& POLLIN_SET
) && (in
& bit
)) {
465 if ((mask
& POLLOUT_SET
) && (out
& bit
)) {
470 if ((mask
& POLLEX_SET
) && (ex
& bit
)) {
486 if (retval
|| timed_out
|| signal_pending(current
))
489 retval
= table
.error
;
494 * If this is the first loop and we have a timeout
495 * given, then we convert to ktime_t and set the to
496 * pointer to the expiry value.
498 if (end_time
&& !to
) {
499 expire
= timespec_to_ktime(*end_time
);
503 if (!poll_schedule_timeout(&table
, TASK_INTERRUPTIBLE
,
508 poll_freewait(&table
);
514 * We can actually return ERESTARTSYS instead of EINTR, but I'd
515 * like to be certain this leads to no problems. So I return
516 * EINTR just for safety.
518 * Update: ERESTARTSYS breaks at least the xview clock binary, so
519 * I'm trying ERESTARTNOHAND which restart only when you want to.
521 #define MAX_SELECT_SECONDS \
522 ((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1)
524 int core_sys_select(int n
, fd_set __user
*inp
, fd_set __user
*outp
,
525 fd_set __user
*exp
, struct timespec
*end_time
)
532 /* Allocate small arguments on the stack to save memory and be faster */
533 long stack_fds
[SELECT_STACK_ALLOC
/sizeof(long)];
539 /* max_fds can increase, so grab it once to avoid race */
541 fdt
= files_fdtable(current
->files
);
542 max_fds
= fdt
->max_fds
;
548 * We need 6 bitmaps (in/out/ex for both incoming and outgoing),
549 * since we used fdset we need to allocate memory in units of
554 if (size
> sizeof(stack_fds
) / 6) {
555 /* Not enough space in on-stack array; must use kmalloc */
557 bits
= kmalloc(6 * size
, GFP_KERNEL
);
562 fds
.out
= bits
+ size
;
563 fds
.ex
= bits
+ 2*size
;
564 fds
.res_in
= bits
+ 3*size
;
565 fds
.res_out
= bits
+ 4*size
;
566 fds
.res_ex
= bits
+ 5*size
;
568 if ((ret
= get_fd_set(n
, inp
, fds
.in
)) ||
569 (ret
= get_fd_set(n
, outp
, fds
.out
)) ||
570 (ret
= get_fd_set(n
, exp
, fds
.ex
)))
572 zero_fd_set(n
, fds
.res_in
);
573 zero_fd_set(n
, fds
.res_out
);
574 zero_fd_set(n
, fds
.res_ex
);
576 ret
= do_select(n
, &fds
, end_time
);
581 ret
= -ERESTARTNOHAND
;
582 if (signal_pending(current
))
587 if (set_fd_set(n
, inp
, fds
.res_in
) ||
588 set_fd_set(n
, outp
, fds
.res_out
) ||
589 set_fd_set(n
, exp
, fds
.res_ex
))
593 if (bits
!= stack_fds
)
599 SYSCALL_DEFINE5(select
, int, n
, fd_set __user
*, inp
, fd_set __user
*, outp
,
600 fd_set __user
*, exp
, struct timeval __user
*, tvp
)
602 struct timespec end_time
, *to
= NULL
;
607 if (copy_from_user(&tv
, tvp
, sizeof(tv
)))
611 if (poll_select_set_timeout(to
,
612 tv
.tv_sec
+ (tv
.tv_usec
/ USEC_PER_SEC
),
613 (tv
.tv_usec
% USEC_PER_SEC
) * NSEC_PER_USEC
))
617 ret
= core_sys_select(n
, inp
, outp
, exp
, to
);
618 ret
= poll_select_copy_remaining(&end_time
, tvp
, 1, ret
);
623 #ifdef HAVE_SET_RESTORE_SIGMASK
624 static long do_pselect(int n
, fd_set __user
*inp
, fd_set __user
*outp
,
625 fd_set __user
*exp
, struct timespec __user
*tsp
,
626 const sigset_t __user
*sigmask
, size_t sigsetsize
)
628 sigset_t ksigmask
, sigsaved
;
629 struct timespec ts
, end_time
, *to
= NULL
;
633 if (copy_from_user(&ts
, tsp
, sizeof(ts
)))
637 if (poll_select_set_timeout(to
, ts
.tv_sec
, ts
.tv_nsec
))
642 if (sigsetsize
!= sizeof(sigset_t
))
644 if (copy_from_user(&ksigmask
, sigmask
, sizeof(ksigmask
)))
647 sigdelsetmask(&ksigmask
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
648 sigprocmask(SIG_SETMASK
, &ksigmask
, &sigsaved
);
651 ret
= core_sys_select(n
, inp
, outp
, exp
, to
);
652 ret
= poll_select_copy_remaining(&end_time
, tsp
, 0, ret
);
654 if (ret
== -ERESTARTNOHAND
) {
656 * Don't restore the signal mask yet. Let do_signal() deliver
657 * the signal on the way back to userspace, before the signal
661 memcpy(¤t
->saved_sigmask
, &sigsaved
,
663 set_restore_sigmask();
666 sigprocmask(SIG_SETMASK
, &sigsaved
, NULL
);
672 * Most architectures can't handle 7-argument syscalls. So we provide a
673 * 6-argument version where the sixth argument is a pointer to a structure
674 * which has a pointer to the sigset_t itself followed by a size_t containing
677 SYSCALL_DEFINE6(pselect6
, int, n
, fd_set __user
*, inp
, fd_set __user
*, outp
,
678 fd_set __user
*, exp
, struct timespec __user
*, tsp
,
681 size_t sigsetsize
= 0;
682 sigset_t __user
*up
= NULL
;
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 *))))
692 return do_pselect(n
, inp
, outp
, exp
, tsp
, up
, sigsetsize
);
694 #endif /* HAVE_SET_RESTORE_SIGMASK */
696 #ifdef __ARCH_WANT_SYS_OLD_SELECT
697 struct sel_arg_struct
{
699 fd_set __user
*inp
, *outp
, *exp
;
700 struct timeval __user
*tvp
;
703 SYSCALL_DEFINE1(old_select
, struct sel_arg_struct __user
*, arg
)
705 struct sel_arg_struct a
;
707 if (copy_from_user(&a
, arg
, sizeof(a
)))
709 return sys_select(a
.n
, a
.inp
, a
.outp
, a
.exp
, a
.tvp
);
714 struct poll_list
*next
;
716 struct pollfd entries
[0];
719 #define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))
722 * Fish for pollable events on the pollfd->fd file descriptor. We're only
723 * interested in events matching the pollfd->events mask, and the result
724 * matching that mask is both recorded in pollfd->revents and returned. The
725 * pwait poll_table will be used by the fd-provided poll handler for waiting,
728 static inline unsigned int do_pollfd(struct pollfd
*pollfd
, poll_table
*pwait
)
739 file
= fget_light(fd
, &fput_needed
);
742 mask
= DEFAULT_POLLMASK
;
743 if (file
->f_op
&& file
->f_op
->poll
) {
745 pwait
->key
= pollfd
->events
|
747 mask
= file
->f_op
->poll(file
, pwait
);
749 /* Mask out unneeded events. */
750 mask
&= pollfd
->events
| POLLERR
| POLLHUP
;
751 fput_light(file
, fput_needed
);
754 pollfd
->revents
= mask
;
759 static int do_poll(unsigned int nfds
, struct poll_list
*list
,
760 struct poll_wqueues
*wait
, struct timespec
*end_time
)
762 poll_table
* pt
= &wait
->pt
;
763 ktime_t expire
, *to
= NULL
;
764 int timed_out
= 0, count
= 0;
765 unsigned long slack
= 0;
767 /* Optimise the no-wait case */
768 if (end_time
&& !end_time
->tv_sec
&& !end_time
->tv_nsec
) {
773 if (end_time
&& !timed_out
)
774 slack
= estimate_accuracy(end_time
);
777 struct poll_list
*walk
;
779 for (walk
= list
; walk
!= NULL
; walk
= walk
->next
) {
780 struct pollfd
* pfd
, * pfd_end
;
783 pfd_end
= pfd
+ walk
->len
;
784 for (; pfd
!= pfd_end
; pfd
++) {
786 * Fish for events. If we found one, record it
787 * and kill the poll_table, so we don't
788 * needlessly register any other waiters after
789 * this. They'll get immediately deregistered
790 * when we break out and return.
792 if (do_pollfd(pfd
, pt
)) {
799 * All waiters have already been registered, so don't provide
800 * a poll_table to them on the next loop iteration.
805 if (signal_pending(current
))
808 if (count
|| timed_out
)
812 * If this is the first loop and we have a timeout
813 * given, then we convert to ktime_t and set the to
814 * pointer to the expiry value.
816 if (end_time
&& !to
) {
817 expire
= timespec_to_ktime(*end_time
);
821 if (!poll_schedule_timeout(wait
, TASK_INTERRUPTIBLE
, to
, slack
))
827 #define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \
828 sizeof(struct pollfd))
830 int do_sys_poll(struct pollfd __user
*ufds
, unsigned int nfds
,
831 struct timespec
*end_time
)
833 struct poll_wqueues table
;
834 int err
= -EFAULT
, fdcount
, len
, size
;
835 /* Allocate small arguments on the stack to save memory and be
836 faster - use long to make sure the buffer is aligned properly
837 on 64 bit archs to avoid unaligned access */
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
;
843 if (nfds
> rlimit(RLIMIT_NOFILE
))
846 len
= min_t(unsigned int, nfds
, N_STACK_PPS
);
853 if (copy_from_user(walk
->entries
, ufds
+ nfds
-todo
,
854 sizeof(struct pollfd
) * walk
->len
))
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
);
870 poll_initwait(&table
);
871 fdcount
= do_poll(nfds
, head
, &table
, end_time
);
872 poll_freewait(&table
);
874 for (walk
= head
; walk
; walk
= walk
->next
) {
875 struct pollfd
*fds
= walk
->entries
;
878 for (j
= 0; j
< walk
->len
; j
++, ufds
++)
879 if (__put_user(fds
[j
].revents
, &ufds
->revents
))
887 struct poll_list
*pos
= walk
;
895 static long do_restart_poll(struct restart_block
*restart_block
)
897 struct pollfd __user
*ufds
= restart_block
->poll
.ufds
;
898 int nfds
= restart_block
->poll
.nfds
;
899 struct timespec
*to
= NULL
, end_time
;
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
;
908 ret
= do_sys_poll(ufds
, nfds
, to
);
911 restart_block
->fn
= do_restart_poll
;
912 ret
= -ERESTART_RESTARTBLOCK
;
917 SYSCALL_DEFINE3(poll
, struct pollfd __user
*, ufds
, unsigned int, nfds
,
920 struct timespec end_time
, *to
= NULL
;
923 if (timeout_msecs
>= 0) {
925 poll_select_set_timeout(to
, timeout_msecs
/ MSEC_PER_SEC
,
926 NSEC_PER_MSEC
* (timeout_msecs
% MSEC_PER_SEC
));
929 ret
= do_sys_poll(ufds
, nfds
, to
);
932 struct restart_block
*restart_block
;
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
;
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;
944 restart_block
->poll
.has_timeout
= 0;
946 ret
= -ERESTART_RESTARTBLOCK
;
951 #ifdef HAVE_SET_RESTORE_SIGMASK
952 SYSCALL_DEFINE5(ppoll
, struct pollfd __user
*, ufds
, unsigned int, nfds
,
953 struct timespec __user
*, tsp
, const sigset_t __user
*, sigmask
,
956 sigset_t ksigmask
, sigsaved
;
957 struct timespec ts
, end_time
, *to
= NULL
;
961 if (copy_from_user(&ts
, tsp
, sizeof(ts
)))
965 if (poll_select_set_timeout(to
, ts
.tv_sec
, ts
.tv_nsec
))
970 if (sigsetsize
!= sizeof(sigset_t
))
972 if (copy_from_user(&ksigmask
, sigmask
, sizeof(ksigmask
)))
975 sigdelsetmask(&ksigmask
, sigmask(SIGKILL
)|sigmask(SIGSTOP
));
976 sigprocmask(SIG_SETMASK
, &ksigmask
, &sigsaved
);
979 ret
= do_sys_poll(ufds
, nfds
, to
);
981 /* We can restart this syscall, usually */
984 * Don't restore the signal mask yet. Let do_signal() deliver
985 * the signal on the way back to userspace, before the signal
989 memcpy(¤t
->saved_sigmask
, &sigsaved
,
991 set_restore_sigmask();
993 ret
= -ERESTARTNOHAND
;
995 sigprocmask(SIG_SETMASK
, &sigsaved
, NULL
);
997 ret
= poll_select_copy_remaining(&end_time
, tsp
, 0, ret
);
1001 #endif /* HAVE_SET_RESTORE_SIGMASK */