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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>
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +040043#include <linux/hash.h>
Richard Cochran0606f422011-02-01 13:52:35 +000044#include <linux/posix-clock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045#include <linux/posix-timers.h>
46#include <linux/syscalls.h>
47#include <linux/wait.h>
48#include <linux/workqueue.h>
Paul Gortmaker9984de12011-05-23 14:51:41 -040049#include <linux/export.h>
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +040050#include <linux/hashtable.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Linus Torvalds1da177e2005-04-16 15:20:36 -070052/*
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +040053 * Management arrays for POSIX timers. Timers are now kept in static hash table
54 * with 512 entries.
55 * Timer ids are allocated by local routine, which selects proper hash head by
56 * key, constructed from current->signal address and per signal struct counter.
57 * This keeps timer ids unique per process, but now they can intersect between
58 * processes.
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 */
60
61/*
62 * Lets keep our timers in a slab cache :-)
63 */
Christoph Lametere18b8902006-12-06 20:33:20 -080064static struct kmem_cache *posix_timers_cache;
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +040065
66static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
67static DEFINE_SPINLOCK(hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 * we assume that the new SIGEV_THREAD_ID shares no bits with the other
71 * SIGEV values. Here we put out an error if this assumption fails.
72 */
73#if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
74 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
75#error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
76#endif
77
Thomas Gleixner65da5282011-02-01 13:51:01 +000078/*
79 * parisc wants ENOTSUP instead of EOPNOTSUPP
80 */
81#ifndef ENOTSUP
82# define ENANOSLEEP_NOTSUP EOPNOTSUPP
83#else
84# define ENANOSLEEP_NOTSUP ENOTSUP
85#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
87/*
88 * The timer ID is turned into a timer address by idr_find().
89 * Verifying a valid ID consists of:
90 *
91 * a) checking that idr_find() returns other than -1.
92 * b) checking that the timer id matches the one in the timer itself.
93 * c) that the timer owner is in the callers thread group.
94 */
95
96/*
97 * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
98 * to implement others. This structure defines the various
Richard Cochran00617482011-02-01 13:52:15 +000099 * clocks.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 *
101 * RESOLUTION: Clock resolution is used to round up timer and interval
102 * times, NOT to report clock times, which are reported with as
103 * much resolution as the system can muster. In some cases this
104 * resolution may depend on the underlying clock hardware and
105 * may not be quantifiable until run time, and only then is the
106 * necessary code is written. The standard says we should say
107 * something about this issue in the documentation...
108 *
Richard Cochran00617482011-02-01 13:52:15 +0000109 * FUNCTIONS: The CLOCKs structure defines possible functions to
110 * handle various clock functions.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 *
Richard Cochran00617482011-02-01 13:52:15 +0000112 * The standard POSIX timer management code assumes the
113 * following: 1.) The k_itimer struct (sched.h) is used for
114 * the timer. 2.) The list, it_lock, it_clock, it_id and
115 * it_pid fields are not modified by timer code.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 *
117 * Permissions: It is assumed that the clock_settime() function defined
118 * for each clock will take care of permission checks. Some
119 * clocks may be set able by any user (i.e. local process
120 * clocks) others not. Currently the only set able clock we
121 * have is CLOCK_REALTIME and its high res counter part, both of
122 * which we beg off on and pass to do_sys_settimeofday().
123 */
124
125static struct k_clock posix_clocks[MAX_CLOCKS];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800127/*
128 * These ones are defined below.
129 */
130static int common_nsleep(const clockid_t, int flags, struct timespec *t,
131 struct timespec __user *rmtp);
Thomas Gleixner838394f2011-02-01 13:51:58 +0000132static int common_timer_create(struct k_itimer *new_timer);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800133static void common_timer_get(struct k_itimer *, struct itimerspec *);
134static int common_timer_set(struct k_itimer *, int,
135 struct itimerspec *, struct itimerspec *);
136static int common_timer_del(struct k_itimer *timer);
137
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800138static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139
Namhyung Kim20f33a02010-10-20 15:57:34 -0700140static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
141
142#define lock_timer(tid, flags) \
143({ struct k_itimer *__timr; \
144 __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
145 __timr; \
146})
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +0400148static int hash(struct signal_struct *sig, unsigned int nr)
149{
150 return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable));
151}
152
153static struct k_itimer *__posix_timers_find(struct hlist_head *head,
154 struct signal_struct *sig,
155 timer_t id)
156{
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +0400157 struct k_itimer *timer;
158
159 hlist_for_each_entry_rcu(timer, head, t_hash) {
160 if ((timer->it_signal == sig) && (timer->it_id == id))
161 return timer;
162 }
163 return NULL;
164}
165
166static struct k_itimer *posix_timer_by_id(timer_t id)
167{
168 struct signal_struct *sig = current->signal;
169 struct hlist_head *head = &posix_timers_hashtable[hash(sig, id)];
170
171 return __posix_timers_find(head, sig, id);
172}
173
174static int posix_timer_add(struct k_itimer *timer)
175{
176 struct signal_struct *sig = current->signal;
177 int first_free_id = sig->posix_timer_id;
178 struct hlist_head *head;
179 int ret = -ENOENT;
180
181 do {
182 spin_lock(&hash_lock);
183 head = &posix_timers_hashtable[hash(sig, sig->posix_timer_id)];
184 if (!__posix_timers_find(head, sig, sig->posix_timer_id)) {
185 hlist_add_head_rcu(&timer->t_hash, head);
186 ret = sig->posix_timer_id;
187 }
188 if (++sig->posix_timer_id < 0)
189 sig->posix_timer_id = 0;
190 if ((sig->posix_timer_id == first_free_id) && (ret == -ENOENT))
191 /* Loop over all possible ids completed */
192 ret = -EAGAIN;
193 spin_unlock(&hash_lock);
194 } while (ret == -ENOENT);
195 return ret;
196}
197
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
199{
200 spin_unlock_irqrestore(&timr->it_lock, flags);
201}
202
Thomas Gleixner42285772011-02-01 13:51:50 +0000203/* Get clock_realtime */
204static int posix_clock_realtime_get(clockid_t which_clock, struct timespec *tp)
205{
206 ktime_get_real_ts(tp);
207 return 0;
208}
209
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000210/* Set clock_realtime */
211static int posix_clock_realtime_set(const clockid_t which_clock,
212 const struct timespec *tp)
213{
214 return do_sys_settimeofday(tp, NULL);
215}
216
Richard Cochranf1f1d5e2011-02-01 13:52:26 +0000217static int posix_clock_realtime_adj(const clockid_t which_clock,
218 struct timex *t)
219{
220 return do_adjtimex(t);
221}
222
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800223/*
224 * Get monotonic time for posix timers
225 */
226static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
227{
228 ktime_get_ts(tp);
229 return 0;
230}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231
232/*
John Stultz7fdd7f82011-02-15 10:52:57 -0800233 * Get monotonic-raw time for posix timers
John Stultz2d422442008-08-20 16:37:30 -0700234 */
235static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
236{
237 getrawmonotonic(tp);
238 return 0;
239}
240
john stultzda15cfd2009-08-19 19:13:34 -0700241
242static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
243{
244 *tp = current_kernel_time();
245 return 0;
246}
247
248static int posix_get_monotonic_coarse(clockid_t which_clock,
249 struct timespec *tp)
250{
251 *tp = get_monotonic_coarse();
252 return 0;
253}
254
H Hartley Sweeten6622e672010-02-02 14:41:42 -0800255static int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
john stultzda15cfd2009-08-19 19:13:34 -0700256{
257 *tp = ktime_to_timespec(KTIME_LOW_RES);
258 return 0;
259}
John Stultz7fdd7f82011-02-15 10:52:57 -0800260
261static int posix_get_boottime(const clockid_t which_clock, struct timespec *tp)
262{
263 get_monotonic_boottime(tp);
264 return 0;
265}
266
John Stultz1ff3c962012-05-03 12:43:40 -0700267static int posix_get_tai(clockid_t which_clock, struct timespec *tp)
268{
269 timekeeping_clocktai(tp);
270 return 0;
271}
John Stultz7fdd7f82011-02-15 10:52:57 -0800272
John Stultz2d422442008-08-20 16:37:30 -0700273/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 * Initialize everything, well, just everything in Posix clocks/timers ;)
275 */
276static __init int init_posix_timers(void)
277{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800278 struct k_clock clock_realtime = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000279 .clock_getres = hrtimer_get_res,
Thomas Gleixner42285772011-02-01 13:51:50 +0000280 .clock_get = posix_clock_realtime_get,
Thomas Gleixner26f9a472011-02-01 13:51:48 +0000281 .clock_set = posix_clock_realtime_set,
Richard Cochranf1f1d5e2011-02-01 13:52:26 +0000282 .clock_adj = posix_clock_realtime_adj,
Thomas Gleixnera5cd2882011-02-01 13:51:11 +0000283 .nsleep = common_nsleep,
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +0000284 .nsleep_restart = hrtimer_nanosleep_restart,
Thomas Gleixner838394f2011-02-01 13:51:58 +0000285 .timer_create = common_timer_create,
Thomas Gleixner27722df2011-02-01 13:52:01 +0000286 .timer_set = common_timer_set,
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000287 .timer_get = common_timer_get,
Thomas Gleixner6761c672011-02-01 13:52:07 +0000288 .timer_del = common_timer_del,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 };
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800290 struct k_clock clock_monotonic = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000291 .clock_getres = hrtimer_get_res,
292 .clock_get = posix_ktime_get_ts,
Thomas Gleixnera5cd2882011-02-01 13:51:11 +0000293 .nsleep = common_nsleep,
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +0000294 .nsleep_restart = hrtimer_nanosleep_restart,
Thomas Gleixner838394f2011-02-01 13:51:58 +0000295 .timer_create = common_timer_create,
Thomas Gleixner27722df2011-02-01 13:52:01 +0000296 .timer_set = common_timer_set,
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000297 .timer_get = common_timer_get,
Thomas Gleixner6761c672011-02-01 13:52:07 +0000298 .timer_del = common_timer_del,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 };
John Stultz2d422442008-08-20 16:37:30 -0700300 struct k_clock clock_monotonic_raw = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000301 .clock_getres = hrtimer_get_res,
302 .clock_get = posix_get_monotonic_raw,
John Stultz2d422442008-08-20 16:37:30 -0700303 };
john stultzda15cfd2009-08-19 19:13:34 -0700304 struct k_clock clock_realtime_coarse = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000305 .clock_getres = posix_get_coarse_res,
306 .clock_get = posix_get_realtime_coarse,
john stultzda15cfd2009-08-19 19:13:34 -0700307 };
308 struct k_clock clock_monotonic_coarse = {
Thomas Gleixner2fd1f042011-02-01 13:51:03 +0000309 .clock_getres = posix_get_coarse_res,
310 .clock_get = posix_get_monotonic_coarse,
john stultzda15cfd2009-08-19 19:13:34 -0700311 };
John Stultz1ff3c962012-05-03 12:43:40 -0700312 struct k_clock clock_tai = {
313 .clock_getres = hrtimer_get_res,
314 .clock_get = posix_get_tai,
John Stultz90adda92013-01-21 17:00:11 -0800315 .nsleep = common_nsleep,
316 .nsleep_restart = hrtimer_nanosleep_restart,
317 .timer_create = common_timer_create,
318 .timer_set = common_timer_set,
319 .timer_get = common_timer_get,
320 .timer_del = common_timer_del,
John Stultz1ff3c962012-05-03 12:43:40 -0700321 };
John Stultz7fdd7f82011-02-15 10:52:57 -0800322 struct k_clock clock_boottime = {
323 .clock_getres = hrtimer_get_res,
324 .clock_get = posix_get_boottime,
325 .nsleep = common_nsleep,
326 .nsleep_restart = hrtimer_nanosleep_restart,
327 .timer_create = common_timer_create,
328 .timer_set = common_timer_set,
329 .timer_get = common_timer_get,
330 .timer_del = common_timer_del,
331 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
Thomas Gleixner52708732011-02-02 12:10:09 +0100333 posix_timers_register_clock(CLOCK_REALTIME, &clock_realtime);
334 posix_timers_register_clock(CLOCK_MONOTONIC, &clock_monotonic);
335 posix_timers_register_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
336 posix_timers_register_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
337 posix_timers_register_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
John Stultz7fdd7f82011-02-15 10:52:57 -0800338 posix_timers_register_clock(CLOCK_BOOTTIME, &clock_boottime);
John Stultz1ff3c962012-05-03 12:43:40 -0700339 posix_timers_register_clock(CLOCK_TAI, &clock_tai);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
341 posix_timers_cache = kmem_cache_create("posix_timers_cache",
Alexey Dobriyan040b5c62007-10-16 23:26:10 -0700342 sizeof (struct k_itimer), 0, SLAB_PANIC,
343 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 return 0;
345}
346
347__initcall(init_posix_timers);
348
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349static void schedule_next_timer(struct k_itimer *timr)
350{
Roman Zippel44f21472006-03-26 01:38:06 -0800351 struct hrtimer *timer = &timr->it.real.timer;
352
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800353 if (timr->it.real.interval.tv64 == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return;
355
Davide Libenzi4d672e72008-02-04 22:27:26 -0800356 timr->it_overrun += (unsigned int) hrtimer_forward(timer,
357 timer->base->get_time(),
358 timr->it.real.interval);
Roman Zippel44f21472006-03-26 01:38:06 -0800359
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 timr->it_overrun_last = timr->it_overrun;
361 timr->it_overrun = -1;
362 ++timr->it_requeue_pending;
Roman Zippel44f21472006-03-26 01:38:06 -0800363 hrtimer_restart(timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364}
365
366/*
367 * This function is exported for use by the signal deliver code. It is
368 * called just prior to the info block being released and passes that
369 * block to us. It's function is to update the overrun entry AND to
370 * restart the timer. It should only be called if the timer is to be
371 * restarted (i.e. we have flagged this in the sys_private entry of the
372 * info block).
373 *
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300374 * To protect against the timer going away while the interrupt is queued,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 * we require that the it_requeue_pending flag be set.
376 */
377void do_schedule_next_timer(struct siginfo *info)
378{
379 struct k_itimer *timr;
380 unsigned long flags;
381
382 timr = lock_timer(info->si_tid, &flags);
383
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800384 if (timr && timr->it_requeue_pending == info->si_sys_private) {
385 if (timr->it_clock < 0)
386 posix_cpu_timer_schedule(timr);
387 else
388 schedule_next_timer(timr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389
Oleg Nesterov54da1172008-07-23 20:52:05 +0400390 info->si_overrun += timr->it_overrun_last;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800391 }
392
Thomas Gleixnerb6557fb2006-02-01 03:05:09 -0800393 if (timr)
394 unlock_timer(timr, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395}
396
Oleg Nesterovba661292008-07-23 20:52:05 +0400397int posix_timer_event(struct k_itimer *timr, int si_private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398{
Oleg Nesterov27af4242008-12-01 14:18:13 -0800399 struct task_struct *task;
400 int shared, ret = -1;
Oleg Nesterovba661292008-07-23 20:52:05 +0400401 /*
402 * FIXME: if ->sigq is queued we can race with
403 * dequeue_signal()->do_schedule_next_timer().
404 *
405 * If dequeue_signal() sees the "right" value of
406 * si_sys_private it calls do_schedule_next_timer().
407 * We re-queue ->sigq and drop ->it_lock().
408 * do_schedule_next_timer() locks the timer
409 * and re-schedules it while ->sigq is pending.
410 * Not really bad, but not that we want.
411 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 timr->sigq->info.si_sys_private = si_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413
Oleg Nesterov27af4242008-12-01 14:18:13 -0800414 rcu_read_lock();
415 task = pid_task(timr->it_pid, PIDTYPE_PID);
416 if (task) {
417 shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
418 ret = send_sigqueue(timr->sigq, task, shared);
419 }
420 rcu_read_unlock();
Oleg Nesterov4aa73612008-09-22 14:42:46 -0700421 /* If we failed to send the signal the timer stops. */
422 return ret > 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423}
424EXPORT_SYMBOL_GPL(posix_timer_event);
425
426/*
427 * This function gets called when a POSIX.1b interval timer expires. It
428 * is used as a callback from the kernel internal timer. The
429 * run_timer_list code ALWAYS calls with interrupts on.
430
431 * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
432 */
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800433static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434{
Roman Zippel05cfb612006-03-26 01:38:12 -0800435 struct k_itimer *timr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 unsigned long flags;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800437 int si_private = 0;
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800438 enum hrtimer_restart ret = HRTIMER_NORESTART;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
Roman Zippel05cfb612006-03-26 01:38:12 -0800440 timr = container_of(timer, struct k_itimer, it.real.timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 spin_lock_irqsave(&timr->it_lock, flags);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800442
443 if (timr->it.real.interval.tv64 != 0)
444 si_private = ++timr->it_requeue_pending;
445
446 if (posix_timer_event(timr, si_private)) {
447 /*
448 * signal was not sent because of sig_ignor
449 * we will not get a call back to restart it AND
450 * it should be restarted.
451 */
452 if (timr->it.real.interval.tv64 != 0) {
Thomas Gleixner58229a12007-06-21 20:45:15 +0000453 ktime_t now = hrtimer_cb_get_time(timer);
454
455 /*
456 * FIXME: What we really want, is to stop this
457 * timer completely and restart it in case the
458 * SIG_IGN is removed. This is a non trivial
459 * change which involves sighand locking
460 * (sigh !), which we don't want to do late in
461 * the release cycle.
462 *
463 * For now we just let timers with an interval
464 * less than a jiffie expire every jiffie to
465 * avoid softirq starvation in case of SIG_IGN
466 * and a very small interval, which would put
467 * the timer right back on the softirq pending
468 * list. By moving now ahead of time we trick
469 * hrtimer_forward() to expire the timer
470 * later, while we still maintain the overrun
471 * accuracy, but have some inconsistency in
472 * the timer_gettime() case. This is at least
473 * better than a starved softirq. A more
474 * complex fix which solves also another related
475 * inconsistency is already in the pipeline.
476 */
477#ifdef CONFIG_HIGH_RES_TIMERS
478 {
479 ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
480
481 if (timr->it.real.interval.tv64 < kj.tv64)
482 now = ktime_add(now, kj);
483 }
484#endif
Davide Libenzi4d672e72008-02-04 22:27:26 -0800485 timr->it_overrun += (unsigned int)
Thomas Gleixner58229a12007-06-21 20:45:15 +0000486 hrtimer_forward(timer, now,
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800487 timr->it.real.interval);
488 ret = HRTIMER_RESTART;
Roman Zippela0a0c282006-03-16 23:04:01 -0800489 ++timr->it_requeue_pending;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800493 unlock_timer(timr, flags);
494 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495}
496
Oleg Nesterov27af4242008-12-01 14:18:13 -0800497static struct pid *good_sigevent(sigevent_t * event)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498{
499 struct task_struct *rtn = current->group_leader;
500
501 if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
Pavel Emelyanov8dc86af2008-02-08 04:21:52 -0800502 (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
Pavel Emelyanovbac0abd2007-10-18 23:40:18 -0700503 !same_thread_group(rtn, current) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
505 return NULL;
506
507 if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
508 ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
509 return NULL;
510
Oleg Nesterov27af4242008-12-01 14:18:13 -0800511 return task_pid(rtn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512}
513
Thomas Gleixner52708732011-02-02 12:10:09 +0100514void posix_timers_register_clock(const clockid_t clock_id,
515 struct k_clock *new_clock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516{
517 if ((unsigned) clock_id >= MAX_CLOCKS) {
Thomas Gleixner4359ac02011-02-02 11:45:23 +0100518 printk(KERN_WARNING "POSIX clock register failed for clock_id %d\n",
519 clock_id);
520 return;
521 }
522
523 if (!new_clock->clock_get) {
524 printk(KERN_WARNING "POSIX clock id %d lacks clock_get()\n",
525 clock_id);
526 return;
527 }
528 if (!new_clock->clock_getres) {
529 printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 clock_id);
531 return;
532 }
533
534 posix_clocks[clock_id] = *new_clock;
535}
Thomas Gleixner52708732011-02-02 12:10:09 +0100536EXPORT_SYMBOL_GPL(posix_timers_register_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
538static struct k_itimer * alloc_posix_timer(void)
539{
540 struct k_itimer *tmr;
Robert P. J. Dayc3762222007-02-10 01:45:03 -0800541 tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 if (!tmr)
543 return tmr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
545 kmem_cache_free(posix_timers_cache, tmr);
Dan Carpenteraa94fbd2008-10-02 14:50:14 -0700546 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 }
Oleg Nesterovba661292008-07-23 20:52:05 +0400548 memset(&tmr->sigq->info, 0, sizeof(siginfo_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 return tmr;
550}
551
Eric Dumazet8af08872011-05-24 11:12:58 +0200552static void k_itimer_rcu_free(struct rcu_head *head)
553{
554 struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
555
556 kmem_cache_free(posix_timers_cache, tmr);
557}
558
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559#define IT_ID_SET 1
560#define IT_ID_NOT_SET 0
561static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
562{
563 if (it_id_set) {
564 unsigned long flags;
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +0400565 spin_lock_irqsave(&hash_lock, flags);
566 hlist_del_rcu(&tmr->t_hash);
567 spin_unlock_irqrestore(&hash_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 }
Oleg Nesterov89992102008-12-01 14:18:15 -0800569 put_pid(tmr->it_pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 sigqueue_free(tmr->sigq);
Eric Dumazet8af08872011-05-24 11:12:58 +0200571 call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572}
573
Thomas Gleixnercc785ac2011-02-01 13:51:09 +0000574static struct k_clock *clockid_to_kclock(const clockid_t id)
575{
576 if (id < 0)
Richard Cochran0606f422011-02-01 13:52:35 +0000577 return (id & CLOCKFD_MASK) == CLOCKFD ?
578 &clock_posix_dynamic : &clock_posix_cpu;
Thomas Gleixnercc785ac2011-02-01 13:51:09 +0000579
580 if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
581 return NULL;
582 return &posix_clocks[id];
583}
584
Thomas Gleixner838394f2011-02-01 13:51:58 +0000585static int common_timer_create(struct k_itimer *new_timer)
586{
587 hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
588 return 0;
589}
590
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591/* Create a POSIX.1b interval timer. */
592
Heiko Carstens362e9c02009-01-14 14:14:07 +0100593SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
594 struct sigevent __user *, timer_event_spec,
595 timer_t __user *, created_timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596{
Thomas Gleixner838394f2011-02-01 13:51:58 +0000597 struct k_clock *kc = clockid_to_kclock(which_clock);
Oleg Nesterov2cd499e2008-09-22 14:42:47 -0700598 struct k_itimer *new_timer;
Oleg Nesterovef864c92008-09-22 14:42:49 -0700599 int error, new_timer_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 sigevent_t event;
601 int it_id_set = IT_ID_NOT_SET;
602
Thomas Gleixner838394f2011-02-01 13:51:58 +0000603 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 return -EINVAL;
Thomas Gleixner838394f2011-02-01 13:51:58 +0000605 if (!kc->timer_create)
606 return -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
608 new_timer = alloc_posix_timer();
609 if (unlikely(!new_timer))
610 return -EAGAIN;
611
612 spin_lock_init(&new_timer->it_lock);
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +0400613 new_timer_id = posix_timer_add(new_timer);
614 if (new_timer_id < 0) {
615 error = new_timer_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 goto out;
617 }
618
619 it_id_set = IT_ID_SET;
620 new_timer->it_id = (timer_t) new_timer_id;
621 new_timer->it_clock = which_clock;
622 new_timer->it_overrun = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 if (timer_event_spec) {
625 if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
626 error = -EFAULT;
627 goto out;
628 }
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700629 rcu_read_lock();
Oleg Nesterov89992102008-12-01 14:18:15 -0800630 new_timer->it_pid = get_pid(good_sigevent(&event));
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700631 rcu_read_unlock();
Oleg Nesterov89992102008-12-01 14:18:15 -0800632 if (!new_timer->it_pid) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 error = -EINVAL;
634 goto out;
635 }
636 } else {
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700637 event.sigev_notify = SIGEV_SIGNAL;
638 event.sigev_signo = SIGALRM;
639 event.sigev_value.sival_int = new_timer->it_id;
Oleg Nesterov89992102008-12-01 14:18:15 -0800640 new_timer->it_pid = get_pid(task_tgid(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 }
642
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700643 new_timer->it_sigev_notify = event.sigev_notify;
644 new_timer->sigq->info.si_signo = event.sigev_signo;
645 new_timer->sigq->info.si_value = event.sigev_value;
Oleg Nesterov717835d2008-09-22 14:42:49 -0700646 new_timer->sigq->info.si_tid = new_timer->it_id;
Oleg Nesterov5a9fa732008-09-22 14:42:50 -0700647 new_timer->sigq->info.si_code = SI_TIMER;
Oleg Nesterov717835d2008-09-22 14:42:49 -0700648
Andrey Vagin2b08de02010-07-20 15:23:14 -0700649 if (copy_to_user(created_timer_id,
650 &new_timer_id, sizeof (new_timer_id))) {
651 error = -EFAULT;
652 goto out;
653 }
654
Thomas Gleixner838394f2011-02-01 13:51:58 +0000655 error = kc->timer_create(new_timer);
Andrey Vagin45e0fff2010-05-24 12:15:33 -0700656 if (error)
657 goto out;
658
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700659 spin_lock_irq(&current->sighand->siglock);
Oleg Nesterov27af4242008-12-01 14:18:13 -0800660 new_timer->it_signal = current->signal;
Oleg Nesterov36b2f042008-09-22 14:42:48 -0700661 list_add(&new_timer->list, &current->signal->posix_timers);
662 spin_unlock_irq(&current->sighand->siglock);
Oleg Nesterovef864c92008-09-22 14:42:49 -0700663
664 return 0;
Thomas Gleixner838394f2011-02-01 13:51:58 +0000665 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 * In the case of the timer belonging to another task, after
667 * the task is unlocked, the timer is owned by the other task
668 * and may cease to exist at any time. Don't use or modify
669 * new_timer after the unlock call.
670 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671out:
Oleg Nesterovef864c92008-09-22 14:42:49 -0700672 release_posix_timer(new_timer, it_id_set);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 return error;
674}
675
676/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 * Locking issues: We need to protect the result of the id look up until
678 * we get the timer locked down so it is not deleted under us. The
679 * removal is done under the idr spinlock so we use that here to bridge
680 * the find to the timer lock. To avoid a dead lock, the timer id MUST
681 * be release with out holding the timer lock.
682 */
Namhyung Kim20f33a02010-10-20 15:57:34 -0700683static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684{
685 struct k_itimer *timr;
Eric Dumazet8af08872011-05-24 11:12:58 +0200686
Tejun Heoe182bb32013-02-20 15:24:12 -0800687 /*
688 * timer_t could be any type >= int and we want to make sure any
689 * @timer_id outside positive int range fails lookup.
690 */
691 if ((unsigned long long)timer_id > INT_MAX)
692 return NULL;
693
Eric Dumazet8af08872011-05-24 11:12:58 +0200694 rcu_read_lock();
Pavel Emelyanov5ed67f02013-03-11 13:12:21 +0400695 timr = posix_timer_by_id(timer_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 if (timr) {
Eric Dumazet8af08872011-05-24 11:12:58 +0200697 spin_lock_irqsave(&timr->it_lock, *flags);
Oleg Nesterov89992102008-12-01 14:18:15 -0800698 if (timr->it_signal == current->signal) {
Eric Dumazet8af08872011-05-24 11:12:58 +0200699 rcu_read_unlock();
Oleg Nesterov31d92842008-09-22 14:42:51 -0700700 return timr;
701 }
Eric Dumazet8af08872011-05-24 11:12:58 +0200702 spin_unlock_irqrestore(&timr->it_lock, *flags);
Oleg Nesterov31d92842008-09-22 14:42:51 -0700703 }
Eric Dumazet8af08872011-05-24 11:12:58 +0200704 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
Oleg Nesterov31d92842008-09-22 14:42:51 -0700706 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707}
708
709/*
710 * Get the time remaining on a POSIX.1b interval timer. This function
711 * is ALWAYS called with spin_lock_irq on the timer, thus it must not
712 * mess with irq.
713 *
714 * We have a couple of messes to clean up here. First there is the case
715 * of a timer that has a requeue pending. These timers should appear to
716 * be in the timer list with an expiry as if we were to requeue them
717 * now.
718 *
719 * The second issue is the SIGEV_NONE timer which may be active but is
720 * not really ever put in the timer list (to save system resources).
721 * This timer may be expired, and if so, we will do it here. Otherwise
722 * it is the same as a requeue pending timer WRT to what we should
723 * report.
724 */
725static void
726common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
727{
Roman Zippel3b98a532006-03-26 01:38:07 -0800728 ktime_t now, remaining, iv;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800729 struct hrtimer *timer = &timr->it.real.timer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800731 memset(cur_setting, 0, sizeof(struct itimerspec));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
Roman Zippel3b98a532006-03-26 01:38:07 -0800733 iv = timr->it.real.interval;
734
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800735 /* interval timer ? */
Roman Zippel3b98a532006-03-26 01:38:07 -0800736 if (iv.tv64)
737 cur_setting->it_interval = ktime_to_timespec(iv);
738 else if (!hrtimer_active(timer) &&
739 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800740 return;
Roman Zippel3b98a532006-03-26 01:38:07 -0800741
742 now = timer->base->get_time();
743
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800744 /*
Roman Zippel3b98a532006-03-26 01:38:07 -0800745 * When a requeue is pending or this is a SIGEV_NONE
746 * timer move the expiry time forward by intervals, so
747 * expiry is > now.
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800748 */
Roman Zippel3b98a532006-03-26 01:38:07 -0800749 if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
750 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
Davide Libenzi4d672e72008-02-04 22:27:26 -0800751 timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
Roman Zippel3b98a532006-03-26 01:38:07 -0800752
Arjan van de Vencc584b22008-09-01 15:02:30 -0700753 remaining = ktime_sub(hrtimer_get_expires(timer), now);
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800754 /* Return 0 only, when the timer is expired and not pending */
Roman Zippel3b98a532006-03-26 01:38:07 -0800755 if (remaining.tv64 <= 0) {
756 /*
757 * A single shot SIGEV_NONE timer must return 0, when
758 * it is expired !
759 */
760 if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
761 cur_setting->it_value.tv_nsec = 1;
762 } else
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800763 cur_setting->it_value = ktime_to_timespec(remaining);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764}
765
766/* Get the time remaining on a POSIX.1b interval timer. */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100767SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
768 struct itimerspec __user *, setting)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 struct itimerspec cur_setting;
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000771 struct k_itimer *timr;
772 struct k_clock *kc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 unsigned long flags;
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000774 int ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775
776 timr = lock_timer(timer_id, &flags);
777 if (!timr)
778 return -EINVAL;
779
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000780 kc = clockid_to_kclock(timr->it_clock);
781 if (WARN_ON_ONCE(!kc || !kc->timer_get))
782 ret = -EINVAL;
783 else
784 kc->timer_get(timr, &cur_setting);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
786 unlock_timer(timr, flags);
787
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000788 if (!ret && copy_to_user(setting, &cur_setting, sizeof (cur_setting)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 return -EFAULT;
790
Thomas Gleixnera7319fa2011-02-01 13:52:04 +0000791 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792}
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800793
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794/*
795 * Get the number of overruns of a POSIX.1b interval timer. This is to
796 * be the overrun of the timer last delivered. At the same time we are
797 * accumulating overruns on the next timer. The overrun is frozen when
798 * the signal is delivered, either at the notify time (if the info block
799 * is not queued) or at the actual delivery time (as we are informed by
800 * the call back to do_schedule_next_timer(). So all we need to do is
801 * to pick up the frozen overrun.
802 */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100803SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804{
805 struct k_itimer *timr;
806 int overrun;
Al Viro5ba25332007-10-14 19:35:50 +0100807 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808
809 timr = lock_timer(timer_id, &flags);
810 if (!timr)
811 return -EINVAL;
812
813 overrun = timr->it_overrun_last;
814 unlock_timer(timr, flags);
815
816 return overrun;
817}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
819/* Set a POSIX.1b interval timer. */
820/* timr->it_lock is taken. */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800821static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822common_timer_set(struct k_itimer *timr, int flags,
823 struct itimerspec *new_setting, struct itimerspec *old_setting)
824{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800825 struct hrtimer *timer = &timr->it.real.timer;
George Anzinger7978672c2006-02-01 03:05:11 -0800826 enum hrtimer_mode mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827
828 if (old_setting)
829 common_timer_get(timr, old_setting);
830
831 /* disable the timer */
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800832 timr->it.real.interval.tv64 = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 /*
834 * careful here. If smp we could be in the "fire" routine which will
835 * be spinning as we hold the lock. But this is ONLY an SMP issue.
836 */
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800837 if (hrtimer_try_to_cancel(timer) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 return TIMER_RETRY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
840 timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
841 ~REQUEUE_PENDING;
842 timr->it_overrun_last = 0;
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800843
844 /* switch off the timer when it_value is zero */
845 if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847
Thomas Gleixnerc9cb2e32007-02-16 01:27:49 -0800848 mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
George Anzinger7978672c2006-02-01 03:05:11 -0800849 hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
George Anzinger7978672c2006-02-01 03:05:11 -0800850 timr->it.real.timer.function = posix_timer_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851
Arjan van de Vencc584b22008-09-01 15:02:30 -0700852 hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800853
854 /* Convert interval */
855 timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
856
857 /* SIGEV_NONE timers are not queued ! See common_timer_get */
Thomas Gleixner952bbc82006-02-01 03:05:13 -0800858 if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
859 /* Setup correct expiry time for relative timers */
Thomas Gleixner5a7780e2008-02-13 09:20:43 +0100860 if (mode == HRTIMER_MODE_REL) {
Arjan van de Vencc584b22008-09-01 15:02:30 -0700861 hrtimer_add_expires(timer, timer->base->get_time());
Thomas Gleixner5a7780e2008-02-13 09:20:43 +0100862 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800863 return 0;
Thomas Gleixner952bbc82006-02-01 03:05:13 -0800864 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800865
Arjan van de Vencc584b22008-09-01 15:02:30 -0700866 hrtimer_start_expires(timer, mode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 return 0;
868}
869
870/* Set a POSIX.1b interval timer */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100871SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
872 const struct itimerspec __user *, new_setting,
873 struct itimerspec __user *, old_setting)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874{
875 struct k_itimer *timr;
876 struct itimerspec new_spec, old_spec;
877 int error = 0;
Al Viro5ba25332007-10-14 19:35:50 +0100878 unsigned long flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 struct itimerspec *rtn = old_setting ? &old_spec : NULL;
Thomas Gleixner27722df2011-02-01 13:52:01 +0000880 struct k_clock *kc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881
882 if (!new_setting)
883 return -EINVAL;
884
885 if (copy_from_user(&new_spec, new_setting, sizeof (new_spec)))
886 return -EFAULT;
887
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800888 if (!timespec_valid(&new_spec.it_interval) ||
889 !timespec_valid(&new_spec.it_value))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 return -EINVAL;
891retry:
892 timr = lock_timer(timer_id, &flag);
893 if (!timr)
894 return -EINVAL;
895
Thomas Gleixner27722df2011-02-01 13:52:01 +0000896 kc = clockid_to_kclock(timr->it_clock);
897 if (WARN_ON_ONCE(!kc || !kc->timer_set))
898 error = -EINVAL;
899 else
900 error = kc->timer_set(timr, flags, &new_spec, rtn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
902 unlock_timer(timr, flag);
903 if (error == TIMER_RETRY) {
904 rtn = NULL; // We already got the old time...
905 goto retry;
906 }
907
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800908 if (old_setting && !error &&
909 copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910 error = -EFAULT;
911
912 return error;
913}
914
Thomas Gleixner6761c672011-02-01 13:52:07 +0000915static int common_timer_del(struct k_itimer *timer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916{
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800917 timer->it.real.interval.tv64 = 0;
Oleg Nesterovf972be32005-06-23 00:09:00 -0700918
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800919 if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 return TIMER_RETRY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 return 0;
922}
923
924static inline int timer_delete_hook(struct k_itimer *timer)
925{
Thomas Gleixner6761c672011-02-01 13:52:07 +0000926 struct k_clock *kc = clockid_to_kclock(timer->it_clock);
927
928 if (WARN_ON_ONCE(!kc || !kc->timer_del))
929 return -EINVAL;
930 return kc->timer_del(timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931}
932
933/* Delete a POSIX.1b interval timer. */
Heiko Carstens362e9c02009-01-14 14:14:07 +0100934SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935{
936 struct k_itimer *timer;
Al Viro5ba25332007-10-14 19:35:50 +0100937 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939retry_delete:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940 timer = lock_timer(timer_id, &flags);
941 if (!timer)
942 return -EINVAL;
943
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800944 if (timer_delete_hook(timer) == TIMER_RETRY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 unlock_timer(timer, flags);
946 goto retry_delete;
947 }
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800948
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949 spin_lock(&current->sighand->siglock);
950 list_del(&timer->list);
951 spin_unlock(&current->sighand->siglock);
952 /*
953 * This keeps any tasks waiting on the spin lock from thinking
954 * they got something (see the lock code above).
955 */
Oleg Nesterov89992102008-12-01 14:18:15 -0800956 timer->it_signal = NULL;
Oleg Nesterov4b7a1302008-07-25 01:47:26 -0700957
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958 unlock_timer(timer, flags);
959 release_posix_timer(timer, IT_ID_SET);
960 return 0;
961}
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800962
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963/*
964 * return timer owned by the process, used by exit_itimers
965 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800966static void itimer_delete(struct k_itimer *timer)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967{
968 unsigned long flags;
969
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970retry_delete:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971 spin_lock_irqsave(&timer->it_lock, flags);
972
Thomas Gleixnerbecf8b52006-01-09 20:52:38 -0800973 if (timer_delete_hook(timer) == TIMER_RETRY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 unlock_timer(timer, flags);
975 goto retry_delete;
976 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977 list_del(&timer->list);
978 /*
979 * This keeps any tasks waiting on the spin lock from thinking
980 * they got something (see the lock code above).
981 */
Oleg Nesterov89992102008-12-01 14:18:15 -0800982 timer->it_signal = NULL;
Oleg Nesterov4b7a1302008-07-25 01:47:26 -0700983
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984 unlock_timer(timer, flags);
985 release_posix_timer(timer, IT_ID_SET);
986}
987
988/*
Roland McGrath25f407f2005-10-21 15:03:29 -0700989 * This is called by do_exit or de_thread, only when there are no more
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 * references to the shared signal_struct.
991 */
992void exit_itimers(struct signal_struct *sig)
993{
994 struct k_itimer *tmr;
995
996 while (!list_empty(&sig->posix_timers)) {
997 tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
998 itimer_delete(tmr);
999 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000}
1001
Heiko Carstens362e9c02009-01-14 14:14:07 +01001002SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
1003 const struct timespec __user *, tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004{
Thomas Gleixner26f9a472011-02-01 13:51:48 +00001005 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 struct timespec new_tp;
1007
Thomas Gleixner26f9a472011-02-01 13:51:48 +00001008 if (!kc || !kc->clock_set)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009 return -EINVAL;
Thomas Gleixner26f9a472011-02-01 13:51:48 +00001010
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 if (copy_from_user(&new_tp, tp, sizeof (*tp)))
1012 return -EFAULT;
1013
Thomas Gleixner26f9a472011-02-01 13:51:48 +00001014 return kc->clock_set(which_clock, &new_tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015}
1016
Heiko Carstens362e9c02009-01-14 14:14:07 +01001017SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
1018 struct timespec __user *,tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019{
Thomas Gleixner42285772011-02-01 13:51:50 +00001020 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021 struct timespec kernel_tp;
1022 int error;
1023
Thomas Gleixner42285772011-02-01 13:51:50 +00001024 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025 return -EINVAL;
Thomas Gleixner42285772011-02-01 13:51:50 +00001026
1027 error = kc->clock_get(which_clock, &kernel_tp);
1028
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029 if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
1030 error = -EFAULT;
1031
1032 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033}
1034
Richard Cochranf1f1d5e2011-02-01 13:52:26 +00001035SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
1036 struct timex __user *, utx)
1037{
1038 struct k_clock *kc = clockid_to_kclock(which_clock);
1039 struct timex ktx;
1040 int err;
1041
1042 if (!kc)
1043 return -EINVAL;
1044 if (!kc->clock_adj)
1045 return -EOPNOTSUPP;
1046
1047 if (copy_from_user(&ktx, utx, sizeof(ktx)))
1048 return -EFAULT;
1049
1050 err = kc->clock_adj(which_clock, &ktx);
1051
Miroslav Lichvarf0dbe812013-01-11 11:58:58 +01001052 if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
Richard Cochranf1f1d5e2011-02-01 13:52:26 +00001053 return -EFAULT;
1054
1055 return err;
1056}
1057
Heiko Carstens362e9c02009-01-14 14:14:07 +01001058SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
1059 struct timespec __user *, tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060{
Thomas Gleixnere5e542e2011-02-01 13:51:53 +00001061 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062 struct timespec rtn_tp;
1063 int error;
1064
Thomas Gleixnere5e542e2011-02-01 13:51:53 +00001065 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 return -EINVAL;
1067
Thomas Gleixnere5e542e2011-02-01 13:51:53 +00001068 error = kc->clock_getres(which_clock, &rtn_tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069
Thomas Gleixnere5e542e2011-02-01 13:51:53 +00001070 if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071 error = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072
1073 return error;
1074}
1075
Linus Torvalds1da177e2005-04-16 15:20:36 -07001076/*
Thomas Gleixner97735f22006-01-09 20:52:37 -08001077 * nanosleep for monotonic and realtime clocks
1078 */
1079static int common_nsleep(const clockid_t which_clock, int flags,
1080 struct timespec *tsave, struct timespec __user *rmtp)
1081{
Oleg Nesterov080344b2008-02-01 17:29:05 +03001082 return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
1083 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1084 which_clock);
Thomas Gleixner97735f22006-01-09 20:52:37 -08001085}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086
Heiko Carstens362e9c02009-01-14 14:14:07 +01001087SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1088 const struct timespec __user *, rqtp,
1089 struct timespec __user *, rmtp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090{
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001091 struct k_clock *kc = clockid_to_kclock(which_clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 struct timespec t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001094 if (!kc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095 return -EINVAL;
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001096 if (!kc->nsleep)
1097 return -ENANOSLEEP_NOTSUP;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098
1099 if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
1100 return -EFAULT;
1101
Thomas Gleixner5f82b2b2006-01-09 20:52:29 -08001102 if (!timespec_valid(&t))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103 return -EINVAL;
1104
Thomas Gleixnera5cd2882011-02-01 13:51:11 +00001105 return kc->nsleep(which_clock, flags, &t, rmtp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106}
Toyo Abe1711ef32006-09-29 02:00:28 -07001107
1108/*
Toyo Abe1711ef32006-09-29 02:00:28 -07001109 * This will restart clock_nanosleep. This is required only by
1110 * compat_clock_nanosleep_restart for now.
1111 */
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001112long clock_nanosleep_restart(struct restart_block *restart_block)
Toyo Abe1711ef32006-09-29 02:00:28 -07001113{
Thomas Gleixnerab8177b2011-05-20 13:05:15 +02001114 clockid_t which_clock = restart_block->nanosleep.clockid;
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001115 struct k_clock *kc = clockid_to_kclock(which_clock);
Toyo Abe1711ef32006-09-29 02:00:28 -07001116
Thomas Gleixner59bd5bc2011-02-01 13:51:17 +00001117 if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))
1118 return -EINVAL;
1119
1120 return kc->nsleep_restart(restart_block);
Toyo Abe1711ef32006-09-29 02:00:28 -07001121}