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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Uwe Zeisbergerf30c2262006-10-03 23:01:26 +02002 * linux/kernel/posix-timers.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 *
5 * 2002-10-15 Posix Clocks & timers
6 * by George Anzinger george@mvista.com
7 *
8 * Copyright (C) 2002 2003 by MontaVista Software.
9 *
10 * 2004-06-01 Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
11 * Copyright (C) 2004 Boris Hu
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
22
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 *
27 * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
28 */
29
30/* These are all the functions necessary to implement
31 * POSIX clocks & timers
32 */
33#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/interrupt.h>
35#include <linux/slab.h>
36#include <linux/time.h>
Arjan van de Ven97d1f152006-03-23 03:00:24 -080037#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <linux/list.h>
41#include <linux/init.h>
42#include <linux/compiler.h>
43#include <linux/idr.h>
44#include <linux/posix-timers.h>
45#include <linux/syscalls.h>
46#include <linux/wait.h>
47#include <linux/workqueue.h>
48#include <linux/module.h>
49
Linus Torvalds1da177e2005-04-16 15:20:36 -070050/*
51 * Management arrays for POSIX timers. Timers are kept in slab memory
52 * Timer ids are allocated by an external routine that keeps track of the
53 * id and the timer. The external interface is:
54 *
55 * void *idr_find(struct idr *idp, int id); to find timer_id <id>
56 * int idr_get_new(struct idr *idp, void *ptr); to get a new id and
57 * related it to <ptr>
58 * void idr_remove(struct idr *idp, int id); to release <id>
59 * void idr_init(struct idr *idp); to initialize <idp>
60 * which we supply.
61 * The idr_get_new *may* call slab for more memory so it must not be
62 * called under a spin lock. Likewise idr_remore may release memory
63 * (but it may be ok to do this under a lock...).
64 * idr_find is just a memory look up and is quite fast. A -1 return
65 * indicates that the requested id does not exist.
66 */
67
68/*
69 * Lets keep our timers in a slab cache :-)
70 */
Christoph Lametere18b8902006-12-06 20:33:20 -080071static struct kmem_cache *posix_timers_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072static struct idr posix_timers_id;
73static DEFINE_SPINLOCK(idr_lock);
74
75/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 * we assume that the new SIGEV_THREAD_ID shares no bits with the other
77 * SIGEV values. Here we put out an error if this assumption fails.
78 */
79#if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
80 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
81#error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
82#endif
83
Thomas Gleixner65da5282011-02-01 13:51:01 +000084/*
85 * parisc wants ENOTSUP instead of EOPNOTSUPP
86 */
87#ifndef ENOTSUP
88# define ENANOSLEEP_NOTSUP EOPNOTSUPP
89#else
90# define ENANOSLEEP_NOTSUP ENOTSUP
91#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
93/*
94 * The timer ID is turned into a timer address by idr_find().
95 * Verifying a valid ID consists of:
96 *
97 * a) checking that idr_find() returns other than -1.
98 * b) checking that the timer id matches the one in the timer itself.
99 * c) that the timer owner is in the callers thread group.
100 */
101
102/*
103 * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
104 * to implement others. This structure defines the various
105 * clocks and allows the possibility of adding others. We
106 * provide an interface to add clocks to the table and expect
107 * the "arch" code to add at least one clock that is high
108 * resolution. Here we define the standard CLOCK_REALTIME as a
109 * 1/HZ resolution clock.
110 *
111 * RESOLUTION: Clock resolution is used to round up timer and interval
112 * times, NOT to report clock times, which are reported with as
113 * much resolution as the system can muster. In some cases this
114 * resolution may depend on the underlying clock hardware and
115 * may not be quantifiable until run time, and only then is the
116 * necessary code is written. The standard says we should say
117 * something about this issue in the documentation...
118 *
119 * FUNCTIONS: The CLOCKs structure defines possible functions to handle
120 * various clock functions. For clocks that use the standard
121 * system timer code these entries should be NULL. This will
122 * allow dispatch without the overhead of indirect function
123 * calls. CLOCKS that depend on other sources (e.g. WWV or GPS)
124 * must supply functions here, even if the function just returns
125 * ENOSYS. The standard POSIX timer management code assumes the
126 * following: 1.) The k_itimer struct (sched.h) is used for the
Oleg Nesterov27af4242008-12-01 14:18:13 -0800127 * timer. 2.) The list, it_lock, it_clock, it_id and it_pid
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 * fields are not modified by timer code.
129 *
130 * At this time all functions EXCEPT clock_nanosleep can be
131 * redirected by the CLOCKS structure. Clock_nanosleep is in
132 * there, but the code ignores it.
133 *
134 * Permissions: It is assumed that the clock_settime() function defined
135 * for each clock will take care of permission checks. Some
136 * clocks may be set able by any user (i.e. local process
137 * clocks) others not. Currently the only set able clock we
138 * have is CLOCK_REALTIME and its high res counter part, both of
139 * which we beg off on and pass to do_sys_settimeofday().
140 */
141
142static struct k_clock posix_clocks[MAX_CLOCKS];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800144/*
145 * These ones are defined below.
146 */
147static int common_nsleep(const clockid_t, int flags, struct timespec *t,
148 struct timespec __user *rmtp);
Thomas Gleixner838394f2011-02-01 13:51:58 +0000149static int common_timer_create(struct k_itimer *new_timer);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800150static void common_timer_get(struct k_itimer *, struct itimerspec *);
151static int common_timer_set(struct k_itimer *, int,
152 struct itimerspec *, struct itimerspec *);
153static int common_timer_del(struct k_itimer *timer);
154
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800155static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
Namhyung Kim20f33a02010-10-20 15:57:34 -0700157static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
158
159#define lock_timer(tid, flags) \
160({ struct k_itimer *__timr; \
161 __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
162 __timr; \
163})
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
165static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
166{
167 spin_unlock_irqrestore(&timr->it_lock, flags);
168}
169
170/*
171 * Call the k_clock hook function if non-null, or the default function.
172 */
173#define CLOCK_DISPATCH(clock, call, arglist) \
174 ((clock) < 0 ? posix_cpu_##call arglist : \
175 (posix_clocks[clock].call != NULL \
176 ? (*posix_clocks[clock].call) arglist : common_##call arglist))
177
178/*
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800179 * Return nonzero if we know a priori this clockid_t value is bogus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 */
Thomas Gleixnera924b042006-01-09 20:52:27 -0800181static inline int invalid_clockid(const clockid_t which_clock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182{
183 if (which_clock < 0) /* CPU clock, posix_cpu_* will check it */
184 return 0;
185 if ((unsigned) which_clock >= MAX_CLOCKS)
186 return 1;
187 if (posix_clocks[which_clock].clock_getres != NULL)
188 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 return 1;
190}
191
Thomas Gleixner42285772011-02-01 13:51:50 +0000192/* Get clock_realtime */
193static int posix_clock_realtime_get(clockid_t which_clock, struct timespec *tp)
194{
195 ktime_get_real_ts(tp);
196 return 0;
197}
198
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000199/* Set clock_realtime */
200static int posix_clock_realtime_set(const clockid_t which_clock,
201 const struct timespec *tp)
202{
203 return do_sys_settimeofday(tp, NULL);
204}
205
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800206/*
207 * Get monotonic time for posix timers
208 */
209static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
210{
211 ktime_get_ts(tp);
212 return 0;
213}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
215/*
John Stultz2d422442008-08-20 16:37:30 -0700216 * Get monotonic time for posix timers
217 */
218static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
219{
220 getrawmonotonic(tp);
221 return 0;
222}
223
john stultzda15cfd2009-08-19 19:13:34 -0700224
225static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
226{
227 *tp = current_kernel_time();
228 return 0;
229}
230
231static int posix_get_monotonic_coarse(clockid_t which_clock,
232 struct timespec *tp)
233{
234 *tp = get_monotonic_coarse();
235 return 0;
236}
237
H Hartley Sweeten6622e672010-02-02 14:41:42 -0800238static int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
john stultzda15cfd2009-08-19 19:13:34 -0700239{
240 *tp = ktime_to_timespec(KTIME_LOW_RES);
241 return 0;
242}
John Stultz2d422442008-08-20 16:37:30 -0700243/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 * Initialize everything, well, just everything in Posix clocks/timers ;)
245 */
246static __init int init_posix_timers(void)
247{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800248 struct k_clock clock_realtime = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000249 .clock_getres = hrtimer_get_res,
Thomas Gleixner42285772011-02-01 13:51:50 +0000250 .clock_get = posix_clock_realtime_get,
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000251 .clock_set = posix_clock_realtime_set,
Thomas Gleixnera5cd2882011-02-01 13:51:11 +0000252 .nsleep = common_nsleep,
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +0000253 .nsleep_restart = hrtimer_nanosleep_restart,
Thomas Gleixner838394f2011-02-01 13:51:58 +0000254 .timer_create = common_timer_create,
Thomas Gleixner27722df2011-02-01 13:52:01 +0000255 .timer_set = common_timer_set,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 };
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800257 struct k_clock clock_monotonic = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000258 .clock_getres = hrtimer_get_res,
259 .clock_get = posix_ktime_get_ts,
Thomas Gleixnera5cd2882011-02-01 13:51:11 +0000260 .nsleep = common_nsleep,
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +0000261 .nsleep_restart = hrtimer_nanosleep_restart,
Thomas Gleixner838394f2011-02-01 13:51:58 +0000262 .timer_create = common_timer_create,
Thomas Gleixner27722df2011-02-01 13:52:01 +0000263 .timer_set = common_timer_set,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 };
John Stultz2d422442008-08-20 16:37:30 -0700265 struct k_clock clock_monotonic_raw = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000266 .clock_getres = hrtimer_get_res,
267 .clock_get = posix_get_monotonic_raw,
John Stultz2d422442008-08-20 16:37:30 -0700268 };
john stultzda15cfd2009-08-19 19:13:34 -0700269 struct k_clock clock_realtime_coarse = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000270 .clock_getres = posix_get_coarse_res,
271 .clock_get = posix_get_realtime_coarse,
john stultzda15cfd2009-08-19 19:13:34 -0700272 };
273 struct k_clock clock_monotonic_coarse = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000274 .clock_getres = posix_get_coarse_res,
275 .clock_get = posix_get_monotonic_coarse,
john stultzda15cfd2009-08-19 19:13:34 -0700276 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
278 register_posix_clock(CLOCK_REALTIME, &clock_realtime);
279 register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
John Stultz2d422442008-08-20 16:37:30 -0700280 register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
john stultzda15cfd2009-08-19 19:13:34 -0700281 register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
282 register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283
284 posix_timers_cache = kmem_cache_create("posix_timers_cache",
Alexey Dobriyan040b5c62007-10-16 23:26:10 -0700285 sizeof (struct k_itimer), 0, SLAB_PANIC,
286 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 idr_init(&posix_timers_id);
288 return 0;
289}
290
291__initcall(init_posix_timers);
292
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293static void schedule_next_timer(struct k_itimer *timr)
294{
Roman Zippel44f21472006-03-26 01:38:06 -0800295 struct hrtimer *timer = &timr->it.real.timer;
296
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800297 if (timr->it.real.interval.tv64 == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 return;
299
Davide Libenzi4d672e72008-02-04 22:27:26 -0800300 timr->it_overrun += (unsigned int) hrtimer_forward(timer,
301 timer->base->get_time(),
302 timr->it.real.interval);
Roman Zippel44f21472006-03-26 01:38:06 -0800303
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 timr->it_overrun_last = timr->it_overrun;
305 timr->it_overrun = -1;
306 ++timr->it_requeue_pending;
Roman Zippel44f21472006-03-26 01:38:06 -0800307 hrtimer_restart(timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308}
309
310/*
311 * This function is exported for use by the signal deliver code. It is
312 * called just prior to the info block being released and passes that
313 * block to us. It's function is to update the overrun entry AND to
314 * restart the timer. It should only be called if the timer is to be
315 * restarted (i.e. we have flagged this in the sys_private entry of the
316 * info block).
317 *
318 * To protect aginst the timer going away while the interrupt is queued,
319 * we require that the it_requeue_pending flag be set.
320 */
321void do_schedule_next_timer(struct siginfo *info)
322{
323 struct k_itimer *timr;
324 unsigned long flags;
325
326 timr = lock_timer(info->si_tid, &flags);
327
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800328 if (timr && timr->it_requeue_pending == info->si_sys_private) {
329 if (timr->it_clock < 0)
330 posix_cpu_timer_schedule(timr);
331 else
332 schedule_next_timer(timr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
Oleg Nesterov54da1172008-07-23 20:52:05 +0400334 info->si_overrun += timr->it_overrun_last;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800335 }
336
Thomas Gleixnerb6557fb2006-02-01 03:05:09 -0800337 if (timr)
338 unlock_timer(timr, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339}
340
Oleg Nesterovba661292008-07-23 20:52:05 +0400341int posix_timer_event(struct k_itimer *timr, int si_private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342{
Oleg Nesterov27af4242008-12-01 14:18:13 -0800343 struct task_struct *task;
344 int shared, ret = -1;
Oleg Nesterovba661292008-07-23 20:52:05 +0400345 /*
346 * FIXME: if ->sigq is queued we can race with
347 * dequeue_signal()->do_schedule_next_timer().
348 *
349 * If dequeue_signal() sees the "right" value of
350 * si_sys_private it calls do_schedule_next_timer().
351 * We re-queue ->sigq and drop ->it_lock().
352 * do_schedule_next_timer() locks the timer
353 * and re-schedules it while ->sigq is pending.
354 * Not really bad, but not that we want.
355 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 timr->sigq->info.si_sys_private = si_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Oleg Nesterov27af4242008-12-01 14:18:13 -0800358 rcu_read_lock();
359 task = pid_task(timr->it_pid, PIDTYPE_PID);
360 if (task) {
361 shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
362 ret = send_sigqueue(timr->sigq, task, shared);
363 }
364 rcu_read_unlock();
Oleg Nesterov4aa73612008-09-22 14:42:46 -0700365 /* If we failed to send the signal the timer stops. */
366 return ret > 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367}
368EXPORT_SYMBOL_GPL(posix_timer_event);
369
370/*
371 * This function gets called when a POSIX.1b interval timer expires. It
372 * is used as a callback from the kernel internal timer. The
373 * run_timer_list code ALWAYS calls with interrupts on.
374
375 * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
376 */
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800377static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378{
Roman Zippel05cfb612006-03-26 01:38:12 -0800379 struct k_itimer *timr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 unsigned long flags;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800381 int si_private = 0;
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800382 enum hrtimer_restart ret = HRTIMER_NORESTART;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
Roman Zippel05cfb612006-03-26 01:38:12 -0800384 timr = container_of(timer, struct k_itimer, it.real.timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 spin_lock_irqsave(&timr->it_lock, flags);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800386
387 if (timr->it.real.interval.tv64 != 0)
388 si_private = ++timr->it_requeue_pending;
389
390 if (posix_timer_event(timr, si_private)) {
391 /*
392 * signal was not sent because of sig_ignor
393 * we will not get a call back to restart it AND
394 * it should be restarted.
395 */
396 if (timr->it.real.interval.tv64 != 0) {
Thomas Gleixner58229a12007-06-21 20:45:15 +0000397 ktime_t now = hrtimer_cb_get_time(timer);
398
399 /*
400 * FIXME: What we really want, is to stop this
401 * timer completely and restart it in case the
402 * SIG_IGN is removed. This is a non trivial
403 * change which involves sighand locking
404 * (sigh !), which we don't want to do late in
405 * the release cycle.
406 *
407 * For now we just let timers with an interval
408 * less than a jiffie expire every jiffie to
409 * avoid softirq starvation in case of SIG_IGN
410 * and a very small interval, which would put
411 * the timer right back on the softirq pending
412 * list. By moving now ahead of time we trick
413 * hrtimer_forward() to expire the timer
414 * later, while we still maintain the overrun
415 * accuracy, but have some inconsistency in
416 * the timer_gettime() case. This is at least
417 * better than a starved softirq. A more
418 * complex fix which solves also another related
419 * inconsistency is already in the pipeline.
420 */
421#ifdef CONFIG_HIGH_RES_TIMERS
422 {
423 ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
424
425 if (timr->it.real.interval.tv64 < kj.tv64)
426 now = ktime_add(now, kj);
427 }
428#endif
Davide Libenzi4d672e72008-02-04 22:27:26 -0800429 timr->it_overrun += (unsigned int)
Thomas Gleixner58229a12007-06-21 20:45:15 +0000430 hrtimer_forward(timer, now,
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800431 timr->it.real.interval);
432 ret = HRTIMER_RESTART;
Roman Zippela0a0c282006-03-16 23:04:01 -0800433 ++timr->it_requeue_pending;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800437 unlock_timer(timr, flags);
438 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439}
440
Oleg Nesterov27af4242008-12-01 14:18:13 -0800441static struct pid *good_sigevent(sigevent_t * event)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442{
443 struct task_struct *rtn = current->group_leader;
444
445 if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
Pavel Emelyanov8dc86af2008-02-08 04:21:52 -0800446 (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
Pavel Emelyanovbac0abd2007-10-18 23:40:18 -0700447 !same_thread_group(rtn, current) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
449 return NULL;
450
451 if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
452 ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
453 return NULL;
454
Oleg Nesterov27af4242008-12-01 14:18:13 -0800455 return task_pid(rtn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456}
457
Thomas Gleixnera924b042006-01-09 20:52:27 -0800458void register_posix_clock(const clockid_t clock_id, struct k_clock *new_clock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459{
460 if ((unsigned) clock_id >= MAX_CLOCKS) {
Thomas Gleixner4359ac02011-02-02 11:45:23 +0100461 printk(KERN_WARNING "POSIX clock register failed for clock_id %d\n",
462 clock_id);
463 return;
464 }
465
466 if (!new_clock->clock_get) {
467 printk(KERN_WARNING "POSIX clock id %d lacks clock_get()\n",
468 clock_id);
469 return;
470 }
471 if (!new_clock->clock_getres) {
472 printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 clock_id);
474 return;
475 }
476
477 posix_clocks[clock_id] = *new_clock;
478}
479EXPORT_SYMBOL_GPL(register_posix_clock);
480
481static struct k_itimer * alloc_posix_timer(void)
482{
483 struct k_itimer *tmr;
Robert P. J. Dayc3762222007-02-10 01:45:03 -0800484 tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 if (!tmr)
486 return tmr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
488 kmem_cache_free(posix_timers_cache, tmr);
Dan Carpenteraa94fbd2008-10-02 14:50:14 -0700489 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 }
Oleg Nesterovba661292008-07-23 20:52:05 +0400491 memset(&tmr->sigq->info, 0, sizeof(siginfo_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 return tmr;
493}
494
495#define IT_ID_SET 1
496#define IT_ID_NOT_SET 0
497static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
498{
499 if (it_id_set) {
500 unsigned long flags;
501 spin_lock_irqsave(&idr_lock, flags);
502 idr_remove(&posix_timers_id, tmr->it_id);
503 spin_unlock_irqrestore(&idr_lock, flags);
504 }
Oleg Nesterov89992102008-12-01 14:18:15 -0800505 put_pid(tmr->it_pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 sigqueue_free(tmr->sigq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 kmem_cache_free(posix_timers_cache, tmr);
508}
509
Thomas Gleixnercc785ac2011-02-01 13:51:09 +0000510static struct k_clock *clockid_to_kclock(const clockid_t id)
511{
512 if (id < 0)
513 return &clock_posix_cpu;
514
515 if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
516 return NULL;
517 return &posix_clocks[id];
518}
519
Thomas Gleixner838394f2011-02-01 13:51:58 +0000520static int common_timer_create(struct k_itimer *new_timer)
521{
522 hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
523 return 0;
524}
525
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526/* Create a POSIX.1b interval timer. */
527
Heiko Carstens362e9c02009-01-14 14:14:07 +0100528SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
529 struct sigevent __user *, timer_event_spec,
530 timer_t __user *, created_timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531{
Thomas Gleixner838394f2011-02-01 13:51:58 +0000532 struct k_clock *kc = clockid_to_kclock(which_clock);
Oleg Nesterov2cd499e2008-09-22 14:42:47 -0700533 struct k_itimer *new_timer;
Oleg Nesterovef864c92008-09-22 14:42:49 -0700534 int error, new_timer_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 sigevent_t event;
536 int it_id_set = IT_ID_NOT_SET;
537
Thomas Gleixner838394f2011-02-01 13:51:58 +0000538 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 return -EINVAL;
Thomas Gleixner838394f2011-02-01 13:51:58 +0000540 if (!kc->timer_create)
541 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542
543 new_timer = alloc_posix_timer();
544 if (unlikely(!new_timer))
545 return -EAGAIN;
546
547 spin_lock_init(&new_timer->it_lock);
548 retry:
549 if (unlikely(!idr_pre_get(&posix_timers_id, GFP_KERNEL))) {
550 error = -EAGAIN;
551 goto out;
552 }
553 spin_lock_irq(&idr_lock);
Oleg Nesterov5a51b712008-09-22 14:42:51 -0700554 error = idr_get_new(&posix_timers_id, new_timer, &new_timer_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 spin_unlock_irq(&idr_lock);
Oleg Nesterovef864c92008-09-22 14:42:49 -0700556 if (error) {
557 if (error == -EAGAIN)
558 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 /*
Joe Perches0b0a3e72008-02-03 17:48:04 +0200560 * Weird looking, but we return EAGAIN if the IDR is
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 * full (proper POSIX return value for this)
562 */
563 error = -EAGAIN;
564 goto out;
565 }
566
567 it_id_set = IT_ID_SET;
568 new_timer->it_id = (timer_t) new_timer_id;
569 new_timer->it_clock = which_clock;
570 new_timer->it_overrun = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 if (timer_event_spec) {
573 if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
574 error = -EFAULT;
575 goto out;
576 }
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700577 rcu_read_lock();
Oleg Nesterov89992102008-12-01 14:18:15 -0800578 new_timer->it_pid = get_pid(good_sigevent(&event));
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700579 rcu_read_unlock();
Oleg Nesterov89992102008-12-01 14:18:15 -0800580 if (!new_timer->it_pid) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 error = -EINVAL;
582 goto out;
583 }
584 } else {
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700585 event.sigev_notify = SIGEV_SIGNAL;
586 event.sigev_signo = SIGALRM;
587 event.sigev_value.sival_int = new_timer->it_id;
Oleg Nesterov89992102008-12-01 14:18:15 -0800588 new_timer->it_pid = get_pid(task_tgid(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
590
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700591 new_timer->it_sigev_notify = event.sigev_notify;
592 new_timer->sigq->info.si_signo = event.sigev_signo;
593 new_timer->sigq->info.si_value = event.sigev_value;
Oleg Nesterov717835d2008-09-22 14:42:49 -0700594 new_timer->sigq->info.si_tid = new_timer->it_id;
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700595 new_timer->sigq->info.si_code = SI_TIMER;
Oleg Nesterov717835d2008-09-22 14:42:49 -0700596
Andrey Vagin2b08de02010-07-20 15:23:14 -0700597 if (copy_to_user(created_timer_id,
598 &new_timer_id, sizeof (new_timer_id))) {
599 error = -EFAULT;
600 goto out;
601 }
602
Thomas Gleixner838394f2011-02-01 13:51:58 +0000603 error = kc->timer_create(new_timer);
Andrey Vagin45e0fff2010-05-24 12:15:33 -0700604 if (error)
605 goto out;
606
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700607 spin_lock_irq(&current->sighand->siglock);
Oleg Nesterov27af4242008-12-01 14:18:13 -0800608 new_timer->it_signal = current->signal;
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700609 list_add(&new_timer->list, &current->signal->posix_timers);
610 spin_unlock_irq(&current->sighand->siglock);
Oleg Nesterovef864c92008-09-22 14:42:49 -0700611
612 return 0;
Thomas Gleixner838394f2011-02-01 13:51:58 +0000613 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 * In the case of the timer belonging to another task, after
615 * the task is unlocked, the timer is owned by the other task
616 * and may cease to exist at any time. Don't use or modify
617 * new_timer after the unlock call.
618 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619out:
Oleg Nesterovef864c92008-09-22 14:42:49 -0700620 release_posix_timer(new_timer, it_id_set);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 return error;
622}
623
624/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 * Locking issues: We need to protect the result of the id look up until
626 * we get the timer locked down so it is not deleted under us. The
627 * removal is done under the idr spinlock so we use that here to bridge
628 * the find to the timer lock. To avoid a dead lock, the timer id MUST
629 * be release with out holding the timer lock.
630 */
Namhyung Kim20f33a02010-10-20 15:57:34 -0700631static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632{
633 struct k_itimer *timr;
634 /*
635 * Watch out here. We do a irqsave on the idr_lock and pass the
636 * flags part over to the timer lock. Must not let interrupts in
637 * while we are moving the lock.
638 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 spin_lock_irqsave(&idr_lock, *flags);
Oleg Nesterov31d92842008-09-22 14:42:51 -0700640 timr = idr_find(&posix_timers_id, (int)timer_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 if (timr) {
642 spin_lock(&timr->it_lock);
Oleg Nesterov89992102008-12-01 14:18:15 -0800643 if (timr->it_signal == current->signal) {
Thomas Gleixner179394a2007-08-22 14:01:37 -0700644 spin_unlock(&idr_lock);
Oleg Nesterov31d92842008-09-22 14:42:51 -0700645 return timr;
646 }
647 spin_unlock(&timr->it_lock);
648 }
649 spin_unlock_irqrestore(&idr_lock, *flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
Oleg Nesterov31d92842008-09-22 14:42:51 -0700651 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652}
653
654/*
655 * Get the time remaining on a POSIX.1b interval timer. This function
656 * is ALWAYS called with spin_lock_irq on the timer, thus it must not
657 * mess with irq.
658 *
659 * We have a couple of messes to clean up here. First there is the case
660 * of a timer that has a requeue pending. These timers should appear to
661 * be in the timer list with an expiry as if we were to requeue them
662 * now.
663 *
664 * The second issue is the SIGEV_NONE timer which may be active but is
665 * not really ever put in the timer list (to save system resources).
666 * This timer may be expired, and if so, we will do it here. Otherwise
667 * it is the same as a requeue pending timer WRT to what we should
668 * report.
669 */
670static void
671common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
672{
Roman Zippel3b98a532006-03-26 01:38:07 -0800673 ktime_t now, remaining, iv;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800674 struct hrtimer *timer = &timr->it.real.timer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800676 memset(cur_setting, 0, sizeof(struct itimerspec));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677
Roman Zippel3b98a532006-03-26 01:38:07 -0800678 iv = timr->it.real.interval;
679
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800680 /* interval timer ? */
Roman Zippel3b98a532006-03-26 01:38:07 -0800681 if (iv.tv64)
682 cur_setting->it_interval = ktime_to_timespec(iv);
683 else if (!hrtimer_active(timer) &&
684 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800685 return;
Roman Zippel3b98a532006-03-26 01:38:07 -0800686
687 now = timer->base->get_time();
688
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800689 /*
Roman Zippel3b98a532006-03-26 01:38:07 -0800690 * When a requeue is pending or this is a SIGEV_NONE
691 * timer move the expiry time forward by intervals, so
692 * expiry is > now.
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800693 */
Roman Zippel3b98a532006-03-26 01:38:07 -0800694 if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
695 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
Davide Libenzi4d672e72008-02-04 22:27:26 -0800696 timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
Roman Zippel3b98a532006-03-26 01:38:07 -0800697
Arjan van de Vencc584b22008-09-01 15:02:30 -0700698 remaining = ktime_sub(hrtimer_get_expires(timer), now);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800699 /* Return 0 only, when the timer is expired and not pending */
Roman Zippel3b98a532006-03-26 01:38:07 -0800700 if (remaining.tv64 <= 0) {
701 /*
702 * A single shot SIGEV_NONE timer must return 0, when
703 * it is expired !
704 */
705 if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
706 cur_setting->it_value.tv_nsec = 1;
707 } else
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800708 cur_setting->it_value = ktime_to_timespec(remaining);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709}
710
711/* Get the time remaining on a POSIX.1b interval timer. */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100712SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
713 struct itimerspec __user *, setting)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714{
715 struct k_itimer *timr;
716 struct itimerspec cur_setting;
717 unsigned long flags;
718
719 timr = lock_timer(timer_id, &flags);
720 if (!timr)
721 return -EINVAL;
722
723 CLOCK_DISPATCH(timr->it_clock, timer_get, (timr, &cur_setting));
724
725 unlock_timer(timr, flags);
726
727 if (copy_to_user(setting, &cur_setting, sizeof (cur_setting)))
728 return -EFAULT;
729
730 return 0;
731}
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800732
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733/*
734 * Get the number of overruns of a POSIX.1b interval timer. This is to
735 * be the overrun of the timer last delivered. At the same time we are
736 * accumulating overruns on the next timer. The overrun is frozen when
737 * the signal is delivered, either at the notify time (if the info block
738 * is not queued) or at the actual delivery time (as we are informed by
739 * the call back to do_schedule_next_timer(). So all we need to do is
740 * to pick up the frozen overrun.
741 */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100742SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743{
744 struct k_itimer *timr;
745 int overrun;
Al Viro5ba25332007-10-14 19:35:50 +0100746 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
748 timr = lock_timer(timer_id, &flags);
749 if (!timr)
750 return -EINVAL;
751
752 overrun = timr->it_overrun_last;
753 unlock_timer(timr, flags);
754
755 return overrun;
756}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
758/* Set a POSIX.1b interval timer. */
759/* timr->it_lock is taken. */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800760static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761common_timer_set(struct k_itimer *timr, int flags,
762 struct itimerspec *new_setting, struct itimerspec *old_setting)
763{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800764 struct hrtimer *timer = &timr->it.real.timer;
George Anzinger7978672c2006-02-01 03:05:11 -0800765 enum hrtimer_mode mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766
767 if (old_setting)
768 common_timer_get(timr, old_setting);
769
770 /* disable the timer */
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800771 timr->it.real.interval.tv64 = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 /*
773 * careful here. If smp we could be in the "fire" routine which will
774 * be spinning as we hold the lock. But this is ONLY an SMP issue.
775 */
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800776 if (hrtimer_try_to_cancel(timer) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777 return TIMER_RETRY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778
779 timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
780 ~REQUEUE_PENDING;
781 timr->it_overrun_last = 0;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800782
783 /* switch off the timer when it_value is zero */
784 if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800787 mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
George Anzinger7978672c2006-02-01 03:05:11 -0800788 hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
George Anzinger7978672c2006-02-01 03:05:11 -0800789 timr->it.real.timer.function = posix_timer_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790
Arjan van de Vencc584b22008-09-01 15:02:30 -0700791 hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800792
793 /* Convert interval */
794 timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
795
796 /* SIGEV_NONE timers are not queued ! See common_timer_get */
Thomas Gleixner952bbc82006-02-01 03:05:13 -0800797 if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
798 /* Setup correct expiry time for relative timers */
Thomas Gleixner5a7780e2008-02-13 09:20:43 +0100799 if (mode == HRTIMER_MODE_REL) {
Arjan van de Vencc584b22008-09-01 15:02:30 -0700800 hrtimer_add_expires(timer, timer->base->get_time());
Thomas Gleixner5a7780e2008-02-13 09:20:43 +0100801 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800802 return 0;
Thomas Gleixner952bbc82006-02-01 03:05:13 -0800803 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800804
Arjan van de Vencc584b22008-09-01 15:02:30 -0700805 hrtimer_start_expires(timer, mode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 return 0;
807}
808
809/* Set a POSIX.1b interval timer */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100810SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
811 const struct itimerspec __user *, new_setting,
812 struct itimerspec __user *, old_setting)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813{
814 struct k_itimer *timr;
815 struct itimerspec new_spec, old_spec;
816 int error = 0;
Al Viro5ba25332007-10-14 19:35:50 +0100817 unsigned long flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 struct itimerspec *rtn = old_setting ? &old_spec : NULL;
Thomas Gleixner27722df2011-02-01 13:52:01 +0000819 struct k_clock *kc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820
821 if (!new_setting)
822 return -EINVAL;
823
824 if (copy_from_user(&new_spec, new_setting, sizeof (new_spec)))
825 return -EFAULT;
826
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800827 if (!timespec_valid(&new_spec.it_interval) ||
828 !timespec_valid(&new_spec.it_value))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 return -EINVAL;
830retry:
831 timr = lock_timer(timer_id, &flag);
832 if (!timr)
833 return -EINVAL;
834
Thomas Gleixner27722df2011-02-01 13:52:01 +0000835 kc = clockid_to_kclock(timr->it_clock);
836 if (WARN_ON_ONCE(!kc || !kc->timer_set))
837 error = -EINVAL;
838 else
839 error = kc->timer_set(timr, flags, &new_spec, rtn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
841 unlock_timer(timr, flag);
842 if (error == TIMER_RETRY) {
843 rtn = NULL; // We already got the old time...
844 goto retry;
845 }
846
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800847 if (old_setting && !error &&
848 copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 error = -EFAULT;
850
851 return error;
852}
853
854static inline int common_timer_del(struct k_itimer *timer)
855{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800856 timer->it.real.interval.tv64 = 0;
Oleg Nesterovf972be32005-06-23 00:09:00 -0700857
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800858 if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 return TIMER_RETRY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860 return 0;
861}
862
863static inline int timer_delete_hook(struct k_itimer *timer)
864{
865 return CLOCK_DISPATCH(timer->it_clock, timer_del, (timer));
866}
867
868/* Delete a POSIX.1b interval timer. */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100869SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870{
871 struct k_itimer *timer;
Al Viro5ba25332007-10-14 19:35:50 +0100872 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874retry_delete:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 timer = lock_timer(timer_id, &flags);
876 if (!timer)
877 return -EINVAL;
878
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800879 if (timer_delete_hook(timer) == TIMER_RETRY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 unlock_timer(timer, flags);
881 goto retry_delete;
882 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800883
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 spin_lock(&current->sighand->siglock);
885 list_del(&timer->list);
886 spin_unlock(&current->sighand->siglock);
887 /*
888 * This keeps any tasks waiting on the spin lock from thinking
889 * they got something (see the lock code above).
890 */
Oleg Nesterov89992102008-12-01 14:18:15 -0800891 timer->it_signal = NULL;
Oleg Nesterov4b7a1302008-07-25 01:47:26 -0700892
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 unlock_timer(timer, flags);
894 release_posix_timer(timer, IT_ID_SET);
895 return 0;
896}
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800897
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898/*
899 * return timer owned by the process, used by exit_itimers
900 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800901static void itimer_delete(struct k_itimer *timer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902{
903 unsigned long flags;
904
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905retry_delete:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 spin_lock_irqsave(&timer->it_lock, flags);
907
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800908 if (timer_delete_hook(timer) == TIMER_RETRY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 unlock_timer(timer, flags);
910 goto retry_delete;
911 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912 list_del(&timer->list);
913 /*
914 * This keeps any tasks waiting on the spin lock from thinking
915 * they got something (see the lock code above).
916 */
Oleg Nesterov89992102008-12-01 14:18:15 -0800917 timer->it_signal = NULL;
Oleg Nesterov4b7a1302008-07-25 01:47:26 -0700918
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 unlock_timer(timer, flags);
920 release_posix_timer(timer, IT_ID_SET);
921}
922
923/*
Roland McGrath25f407f2005-10-21 15:03:29 -0700924 * This is called by do_exit or de_thread, only when there are no more
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 * references to the shared signal_struct.
926 */
927void exit_itimers(struct signal_struct *sig)
928{
929 struct k_itimer *tmr;
930
931 while (!list_empty(&sig->posix_timers)) {
932 tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
933 itimer_delete(tmr);
934 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935}
936
Heiko Carstens362e9c02009-01-14 14:14:07 +0100937SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
938 const struct timespec __user *, tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939{
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000940 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941 struct timespec new_tp;
942
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000943 if (!kc || !kc->clock_set)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 return -EINVAL;
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000945
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946 if (copy_from_user(&new_tp, tp, sizeof (*tp)))
947 return -EFAULT;
948
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000949 return kc->clock_set(which_clock, &new_tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950}
951
Heiko Carstens362e9c02009-01-14 14:14:07 +0100952SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
953 struct timespec __user *,tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954{
Thomas Gleixner42285772011-02-01 13:51:50 +0000955 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956 struct timespec kernel_tp;
957 int error;
958
Thomas Gleixner42285772011-02-01 13:51:50 +0000959 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 return -EINVAL;
Thomas Gleixner42285772011-02-01 13:51:50 +0000961
962 error = kc->clock_get(which_clock, &kernel_tp);
963
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
965 error = -EFAULT;
966
967 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968}
969
Heiko Carstens362e9c02009-01-14 14:14:07 +0100970SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
971 struct timespec __user *, tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972{
Thomas Gleixnere5e542e2011-02-01 13:51:53 +0000973 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 struct timespec rtn_tp;
975 int error;
976
Thomas Gleixnere5e542e2011-02-01 13:51:53 +0000977 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 return -EINVAL;
979
Thomas Gleixnere5e542e2011-02-01 13:51:53 +0000980 error = kc->clock_getres(which_clock, &rtn_tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981
Thomas Gleixnere5e542e2011-02-01 13:51:53 +0000982 if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 error = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984
985 return error;
986}
987
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988/*
Thomas Gleixner97735f22006-01-09 20:52:37 -0800989 * nanosleep for monotonic and realtime clocks
990 */
991static int common_nsleep(const clockid_t which_clock, int flags,
992 struct timespec *tsave, struct timespec __user *rmtp)
993{
Oleg Nesterov080344b2008-02-01 17:29:05 +0300994 return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
995 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
996 which_clock);
Thomas Gleixner97735f22006-01-09 20:52:37 -0800997}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998
Heiko Carstens362e9c02009-01-14 14:14:07 +0100999SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1000 const struct timespec __user *, rqtp,
1001 struct timespec __user *, rmtp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002{
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001003 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 struct timespec t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001006 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 return -EINVAL;
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001008 if (!kc->nsleep)
1009 return -ENANOSLEEP_NOTSUP;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010
1011 if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
1012 return -EFAULT;
1013
Thomas Gleixner5f82b2b2006-01-09 20:52:29 -08001014 if (!timespec_valid(&t))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 return -EINVAL;
1016
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001017 return kc->nsleep(which_clock, flags, &t, rmtp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018}
Toyo Abe1711ef32006-09-29 02:00:28 -07001019
1020/*
Toyo Abe1711ef32006-09-29 02:00:28 -07001021 * This will restart clock_nanosleep. This is required only by
1022 * compat_clock_nanosleep_restart for now.
1023 */
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001024long clock_nanosleep_restart(struct restart_block *restart_block)
Toyo Abe1711ef32006-09-29 02:00:28 -07001025{
Thomas Gleixner3751f9f2011-02-01 13:51:20 +00001026 clockid_t which_clock = restart_block->nanosleep.index;
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001027 struct k_clock *kc = clockid_to_kclock(which_clock);
Toyo Abe1711ef32006-09-29 02:00:28 -07001028
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001029 if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))
1030 return -EINVAL;
1031
1032 return kc->nsleep_restart(restart_block);
Toyo Abe1711ef32006-09-29 02:00:28 -07001033}