Commit | Line | Data |
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35728b82 | 1 | // SPDX-License-Identifier: GPL-2.0 |
ff3ead96 JS |
2 | /* |
3 | * Alarmtimer interface | |
4 | * | |
5 | * This interface provides a timer which is similarto hrtimers, | |
6 | * but triggers a RTC alarm if the box is suspend. | |
7 | * | |
8 | * This interface is influenced by the Android RTC Alarm timer | |
9 | * interface. | |
10 | * | |
11 | * Copyright (C) 2010 IBM Corperation | |
12 | * | |
13 | * Author: John Stultz <john.stultz@linaro.org> | |
ff3ead96 JS |
14 | */ |
15 | #include <linux/time.h> | |
16 | #include <linux/hrtimer.h> | |
17 | #include <linux/timerqueue.h> | |
18 | #include <linux/rtc.h> | |
174cd4b1 | 19 | #include <linux/sched/signal.h> |
b17b0153 | 20 | #include <linux/sched/debug.h> |
ff3ead96 JS |
21 | #include <linux/alarmtimer.h> |
22 | #include <linux/mutex.h> | |
23 | #include <linux/platform_device.h> | |
24 | #include <linux/posix-timers.h> | |
25 | #include <linux/workqueue.h> | |
26 | #include <linux/freezer.h> | |
edbeda46 | 27 | #include <linux/compat.h> |
51218298 | 28 | #include <linux/module.h> |
ff3ead96 | 29 | |
bab0aae9 TG |
30 | #include "posix-timers.h" |
31 | ||
4a057549 BW |
32 | #define CREATE_TRACE_POINTS |
33 | #include <trace/events/alarmtimer.h> | |
34 | ||
180bf812 JS |
35 | /** |
36 | * struct alarm_base - Alarm timer bases | |
37 | * @lock: Lock for syncrhonized access to the base | |
38 | * @timerqueue: Timerqueue head managing the list of events | |
180bf812 JS |
39 | * @gettime: Function to read the time correlating to the base |
40 | * @base_clockid: clockid for the base | |
180bf812 | 41 | */ |
ff3ead96 JS |
42 | static struct alarm_base { |
43 | spinlock_t lock; | |
44 | struct timerqueue_head timerqueue; | |
ff3ead96 JS |
45 | ktime_t (*gettime)(void); |
46 | clockid_t base_clockid; | |
ff3ead96 JS |
47 | } alarm_bases[ALARM_NUMTYPE]; |
48 | ||
b6b3b80f | 49 | #if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS) |
4a057549 BW |
50 | /* freezer information to handle clock_nanosleep triggered wakeups */ |
51 | static enum alarmtimer_type freezer_alarmtype; | |
52 | static ktime_t freezer_expires; | |
c008ba58 JS |
53 | static ktime_t freezer_delta; |
54 | static DEFINE_SPINLOCK(freezer_delta_lock); | |
b6b3b80f | 55 | #endif |
c008ba58 | 56 | |
47b4a457 | 57 | #ifdef CONFIG_RTC_CLASS |
59a93c27 TP |
58 | static struct wakeup_source *ws; |
59 | ||
180bf812 | 60 | /* rtc timer and device for setting alarm wakeups at suspend */ |
c5e14e76 | 61 | static struct rtc_timer rtctimer; |
ff3ead96 | 62 | static struct rtc_device *rtcdev; |
c008ba58 | 63 | static DEFINE_SPINLOCK(rtcdev_lock); |
ff3ead96 | 64 | |
c008ba58 JS |
65 | /** |
66 | * alarmtimer_get_rtcdev - Return selected rtcdevice | |
67 | * | |
68 | * This function returns the rtc device to use for wakealarms. | |
69 | * If one has not already been chosen, it checks to see if a | |
70 | * functional rtc device is available. | |
71 | */ | |
57c498fa | 72 | struct rtc_device *alarmtimer_get_rtcdev(void) |
c008ba58 | 73 | { |
c008ba58 JS |
74 | unsigned long flags; |
75 | struct rtc_device *ret; | |
76 | ||
77 | spin_lock_irqsave(&rtcdev_lock, flags); | |
c008ba58 JS |
78 | ret = rtcdev; |
79 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
80 | ||
81 | return ret; | |
82 | } | |
71d5d2b7 | 83 | EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); |
8bc0dafb JS |
84 | |
85 | static int alarmtimer_rtc_add_device(struct device *dev, | |
86 | struct class_interface *class_intf) | |
87 | { | |
88 | unsigned long flags; | |
89 | struct rtc_device *rtc = to_rtc_device(dev); | |
47b4a457 | 90 | struct wakeup_source *__ws; |
8bc0dafb JS |
91 | |
92 | if (rtcdev) | |
93 | return -EBUSY; | |
94 | ||
95 | if (!rtc->ops->set_alarm) | |
96 | return -1; | |
97 | if (!device_may_wakeup(rtc->dev.parent)) | |
98 | return -1; | |
99 | ||
c8377adf | 100 | __ws = wakeup_source_register(dev, "alarmtimer"); |
47b4a457 | 101 | |
8bc0dafb JS |
102 | spin_lock_irqsave(&rtcdev_lock, flags); |
103 | if (!rtcdev) { | |
51218298 AB |
104 | if (!try_module_get(rtc->owner)) { |
105 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
106 | return -1; | |
107 | } | |
108 | ||
8bc0dafb JS |
109 | rtcdev = rtc; |
110 | /* hold a reference so it doesn't go away */ | |
111 | get_device(dev); | |
47b4a457 GU |
112 | ws = __ws; |
113 | __ws = NULL; | |
8bc0dafb JS |
114 | } |
115 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
47b4a457 GU |
116 | |
117 | wakeup_source_unregister(__ws); | |
118 | ||
8bc0dafb JS |
119 | return 0; |
120 | } | |
121 | ||
c5e14e76 TG |
122 | static inline void alarmtimer_rtc_timer_init(void) |
123 | { | |
124 | rtc_timer_init(&rtctimer, NULL, NULL); | |
125 | } | |
126 | ||
8bc0dafb JS |
127 | static struct class_interface alarmtimer_rtc_interface = { |
128 | .add_dev = &alarmtimer_rtc_add_device, | |
129 | }; | |
130 | ||
4523f6ad | 131 | static int alarmtimer_rtc_interface_setup(void) |
8bc0dafb JS |
132 | { |
133 | alarmtimer_rtc_interface.class = rtc_class; | |
4523f6ad TG |
134 | return class_interface_register(&alarmtimer_rtc_interface); |
135 | } | |
136 | static void alarmtimer_rtc_interface_remove(void) | |
137 | { | |
138 | class_interface_unregister(&alarmtimer_rtc_interface); | |
8bc0dafb | 139 | } |
1c6b39ad | 140 | #else |
57c498fa | 141 | struct rtc_device *alarmtimer_get_rtcdev(void) |
4523f6ad TG |
142 | { |
143 | return NULL; | |
144 | } | |
145 | #define rtcdev (NULL) | |
146 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } | |
147 | static inline void alarmtimer_rtc_interface_remove(void) { } | |
c5e14e76 | 148 | static inline void alarmtimer_rtc_timer_init(void) { } |
c008ba58 | 149 | #endif |
ff3ead96 | 150 | |
180bf812 | 151 | /** |
ff3ead96 JS |
152 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
153 | * @base: pointer to the base where the timer is being run | |
154 | * @alarm: pointer to alarm being enqueued. | |
155 | * | |
dae373be | 156 | * Adds alarm to a alarm_base timerqueue |
ff3ead96 JS |
157 | * |
158 | * Must hold base->lock when calling. | |
159 | */ | |
160 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) | |
161 | { | |
dae373be JS |
162 | if (alarm->state & ALARMTIMER_STATE_ENQUEUED) |
163 | timerqueue_del(&base->timerqueue, &alarm->node); | |
164 | ||
ff3ead96 | 165 | timerqueue_add(&base->timerqueue, &alarm->node); |
a28cde81 | 166 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
167 | } |
168 | ||
180bf812 | 169 | /** |
a65bcc12 | 170 | * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue |
ff3ead96 JS |
171 | * @base: pointer to the base where the timer is running |
172 | * @alarm: pointer to alarm being removed | |
173 | * | |
dae373be | 174 | * Removes alarm to a alarm_base timerqueue |
ff3ead96 JS |
175 | * |
176 | * Must hold base->lock when calling. | |
177 | */ | |
a65bcc12 | 178 | static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) |
ff3ead96 | 179 | { |
a28cde81 JS |
180 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
181 | return; | |
182 | ||
ff3ead96 | 183 | timerqueue_del(&base->timerqueue, &alarm->node); |
a28cde81 | 184 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
185 | } |
186 | ||
7068b7a1 | 187 | |
180bf812 | 188 | /** |
7068b7a1 JS |
189 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
190 | * @timer: pointer to hrtimer being run | |
ff3ead96 | 191 | * |
180bf812 JS |
192 | * When a alarm timer fires, this runs through the timerqueue to |
193 | * see which alarms expired, and runs those. If there are more alarm | |
194 | * timers queued for the future, we set the hrtimer to fire when | |
195 | * when the next future alarm timer expires. | |
ff3ead96 | 196 | */ |
7068b7a1 | 197 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
ff3ead96 | 198 | { |
dae373be JS |
199 | struct alarm *alarm = container_of(timer, struct alarm, timer); |
200 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
ff3ead96 | 201 | unsigned long flags; |
7068b7a1 | 202 | int ret = HRTIMER_NORESTART; |
54da23b7 | 203 | int restart = ALARMTIMER_NORESTART; |
ff3ead96 JS |
204 | |
205 | spin_lock_irqsave(&base->lock, flags); | |
a65bcc12 | 206 | alarmtimer_dequeue(base, alarm); |
dae373be | 207 | spin_unlock_irqrestore(&base->lock, flags); |
54da23b7 | 208 | |
dae373be JS |
209 | if (alarm->function) |
210 | restart = alarm->function(alarm, base->gettime()); | |
ff3ead96 | 211 | |
dae373be JS |
212 | spin_lock_irqsave(&base->lock, flags); |
213 | if (restart != ALARMTIMER_NORESTART) { | |
214 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
215 | alarmtimer_enqueue(base, alarm); | |
7068b7a1 | 216 | ret = HRTIMER_RESTART; |
ff3ead96 JS |
217 | } |
218 | spin_unlock_irqrestore(&base->lock, flags); | |
ff3ead96 | 219 | |
4a057549 | 220 | trace_alarmtimer_fired(alarm, base->gettime()); |
7068b7a1 | 221 | return ret; |
ff3ead96 | 222 | |
ff3ead96 JS |
223 | } |
224 | ||
6cffe00f TP |
225 | ktime_t alarm_expires_remaining(const struct alarm *alarm) |
226 | { | |
227 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
228 | return ktime_sub(alarm->node.expires, base->gettime()); | |
229 | } | |
11682a41 | 230 | EXPORT_SYMBOL_GPL(alarm_expires_remaining); |
6cffe00f | 231 | |
472647dc | 232 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 233 | /** |
ff3ead96 JS |
234 | * alarmtimer_suspend - Suspend time callback |
235 | * @dev: unused | |
ff3ead96 JS |
236 | * |
237 | * When we are going into suspend, we look through the bases | |
238 | * to see which is the soonest timer to expire. We then | |
239 | * set an rtc timer to fire that far into the future, which | |
240 | * will wake us from suspend. | |
241 | */ | |
242 | static int alarmtimer_suspend(struct device *dev) | |
243 | { | |
4a057549 BW |
244 | ktime_t min, now, expires; |
245 | int i, ret, type; | |
c008ba58 | 246 | struct rtc_device *rtc; |
4a057549 BW |
247 | unsigned long flags; |
248 | struct rtc_time tm; | |
ff3ead96 JS |
249 | |
250 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
251 | min = freezer_delta; | |
4a057549 BW |
252 | expires = freezer_expires; |
253 | type = freezer_alarmtype; | |
8b0e1953 | 254 | freezer_delta = 0; |
ff3ead96 JS |
255 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
256 | ||
8bc0dafb | 257 | rtc = alarmtimer_get_rtcdev(); |
ff3ead96 | 258 | /* If we have no rtcdev, just return */ |
c008ba58 | 259 | if (!rtc) |
ff3ead96 JS |
260 | return 0; |
261 | ||
262 | /* Find the soonest timer to expire*/ | |
263 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
264 | struct alarm_base *base = &alarm_bases[i]; | |
265 | struct timerqueue_node *next; | |
266 | ktime_t delta; | |
267 | ||
268 | spin_lock_irqsave(&base->lock, flags); | |
269 | next = timerqueue_getnext(&base->timerqueue); | |
270 | spin_unlock_irqrestore(&base->lock, flags); | |
271 | if (!next) | |
272 | continue; | |
273 | delta = ktime_sub(next->expires, base->gettime()); | |
2456e855 | 274 | if (!min || (delta < min)) { |
4a057549 | 275 | expires = next->expires; |
ff3ead96 | 276 | min = delta; |
4a057549 BW |
277 | type = i; |
278 | } | |
ff3ead96 | 279 | } |
2456e855 | 280 | if (min == 0) |
ff3ead96 JS |
281 | return 0; |
282 | ||
59a93c27 TP |
283 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
284 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); | |
285 | return -EBUSY; | |
286 | } | |
ff3ead96 | 287 | |
4a057549 BW |
288 | trace_alarmtimer_suspend(expires, type); |
289 | ||
ff3ead96 | 290 | /* Setup an rtc timer to fire that far in the future */ |
c008ba58 JS |
291 | rtc_timer_cancel(rtc, &rtctimer); |
292 | rtc_read_time(rtc, &tm); | |
ff3ead96 JS |
293 | now = rtc_tm_to_ktime(tm); |
294 | now = ktime_add(now, min); | |
295 | ||
59a93c27 | 296 | /* Set alarm, if in the past reject suspend briefly to handle */ |
8b0e1953 | 297 | ret = rtc_timer_start(rtc, &rtctimer, now, 0); |
59a93c27 TP |
298 | if (ret < 0) |
299 | __pm_wakeup_event(ws, MSEC_PER_SEC); | |
300 | return ret; | |
ff3ead96 | 301 | } |
a0e3213f | 302 | |
303 | static int alarmtimer_resume(struct device *dev) | |
304 | { | |
305 | struct rtc_device *rtc; | |
306 | ||
307 | rtc = alarmtimer_get_rtcdev(); | |
308 | if (rtc) | |
309 | rtc_timer_cancel(rtc, &rtctimer); | |
310 | return 0; | |
311 | } | |
312 | ||
472647dc JS |
313 | #else |
314 | static int alarmtimer_suspend(struct device *dev) | |
315 | { | |
316 | return 0; | |
317 | } | |
a0e3213f | 318 | |
319 | static int alarmtimer_resume(struct device *dev) | |
320 | { | |
321 | return 0; | |
322 | } | |
472647dc | 323 | #endif |
ff3ead96 | 324 | |
bd031430 TG |
325 | static void |
326 | __alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
327 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) | |
328 | { | |
329 | timerqueue_init(&alarm->node); | |
330 | alarm->timer.function = alarmtimer_fired; | |
331 | alarm->function = function; | |
332 | alarm->type = type; | |
333 | alarm->state = ALARMTIMER_STATE_INACTIVE; | |
334 | } | |
335 | ||
180bf812 | 336 | /** |
ff3ead96 JS |
337 | * alarm_init - Initialize an alarm structure |
338 | * @alarm: ptr to alarm to be initialized | |
339 | * @type: the type of the alarm | |
340 | * @function: callback that is run when the alarm fires | |
ff3ead96 JS |
341 | */ |
342 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
4b41308d | 343 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
ff3ead96 | 344 | { |
dae373be | 345 | hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, |
bd031430 TG |
346 | HRTIMER_MODE_ABS); |
347 | __alarm_init(alarm, type, function); | |
ff3ead96 | 348 | } |
11682a41 | 349 | EXPORT_SYMBOL_GPL(alarm_init); |
ff3ead96 | 350 | |
180bf812 | 351 | /** |
6cffe00f | 352 | * alarm_start - Sets an absolute alarm to fire |
ff3ead96 JS |
353 | * @alarm: ptr to alarm to set |
354 | * @start: time to run the alarm | |
ff3ead96 | 355 | */ |
b193217e | 356 | void alarm_start(struct alarm *alarm, ktime_t start) |
ff3ead96 JS |
357 | { |
358 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
359 | unsigned long flags; | |
360 | ||
361 | spin_lock_irqsave(&base->lock, flags); | |
ff3ead96 | 362 | alarm->node.expires = start; |
ff3ead96 | 363 | alarmtimer_enqueue(base, alarm); |
b193217e | 364 | hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); |
ff3ead96 | 365 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
366 | |
367 | trace_alarmtimer_start(alarm, base->gettime()); | |
ff3ead96 | 368 | } |
11682a41 | 369 | EXPORT_SYMBOL_GPL(alarm_start); |
ff3ead96 | 370 | |
6cffe00f TP |
371 | /** |
372 | * alarm_start_relative - Sets a relative alarm to fire | |
373 | * @alarm: ptr to alarm to set | |
374 | * @start: time relative to now to run the alarm | |
375 | */ | |
b193217e | 376 | void alarm_start_relative(struct alarm *alarm, ktime_t start) |
6cffe00f TP |
377 | { |
378 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
379 | ||
f4781e76 | 380 | start = ktime_add_safe(start, base->gettime()); |
b193217e | 381 | alarm_start(alarm, start); |
6cffe00f | 382 | } |
11682a41 | 383 | EXPORT_SYMBOL_GPL(alarm_start_relative); |
6cffe00f TP |
384 | |
385 | void alarm_restart(struct alarm *alarm) | |
386 | { | |
387 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
388 | unsigned long flags; | |
389 | ||
390 | spin_lock_irqsave(&base->lock, flags); | |
391 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
392 | hrtimer_restart(&alarm->timer); | |
393 | alarmtimer_enqueue(base, alarm); | |
394 | spin_unlock_irqrestore(&base->lock, flags); | |
395 | } | |
11682a41 | 396 | EXPORT_SYMBOL_GPL(alarm_restart); |
6cffe00f | 397 | |
180bf812 | 398 | /** |
9082c465 | 399 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
ff3ead96 | 400 | * @alarm: ptr to alarm to be canceled |
9082c465 JS |
401 | * |
402 | * Returns 1 if the timer was canceled, 0 if it was not running, | |
403 | * and -1 if the callback was running | |
ff3ead96 | 404 | */ |
9082c465 | 405 | int alarm_try_to_cancel(struct alarm *alarm) |
ff3ead96 JS |
406 | { |
407 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
408 | unsigned long flags; | |
dae373be | 409 | int ret; |
9082c465 | 410 | |
dae373be JS |
411 | spin_lock_irqsave(&base->lock, flags); |
412 | ret = hrtimer_try_to_cancel(&alarm->timer); | |
413 | if (ret >= 0) | |
a65bcc12 | 414 | alarmtimer_dequeue(base, alarm); |
ff3ead96 | 415 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
416 | |
417 | trace_alarmtimer_cancel(alarm, base->gettime()); | |
9082c465 | 418 | return ret; |
ff3ead96 | 419 | } |
11682a41 | 420 | EXPORT_SYMBOL_GPL(alarm_try_to_cancel); |
ff3ead96 JS |
421 | |
422 | ||
9082c465 JS |
423 | /** |
424 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done | |
425 | * @alarm: ptr to alarm to be canceled | |
426 | * | |
427 | * Returns 1 if the timer was canceled, 0 if it was not active. | |
428 | */ | |
429 | int alarm_cancel(struct alarm *alarm) | |
430 | { | |
431 | for (;;) { | |
432 | int ret = alarm_try_to_cancel(alarm); | |
433 | if (ret >= 0) | |
434 | return ret; | |
51ae3309 | 435 | hrtimer_cancel_wait_running(&alarm->timer); |
9082c465 JS |
436 | } |
437 | } | |
11682a41 | 438 | EXPORT_SYMBOL_GPL(alarm_cancel); |
9082c465 | 439 | |
dce75a8c JS |
440 | |
441 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) | |
442 | { | |
443 | u64 overrun = 1; | |
444 | ktime_t delta; | |
445 | ||
446 | delta = ktime_sub(now, alarm->node.expires); | |
447 | ||
2456e855 | 448 | if (delta < 0) |
dce75a8c JS |
449 | return 0; |
450 | ||
2456e855 | 451 | if (unlikely(delta >= interval)) { |
dce75a8c JS |
452 | s64 incr = ktime_to_ns(interval); |
453 | ||
454 | overrun = ktime_divns(delta, incr); | |
455 | ||
456 | alarm->node.expires = ktime_add_ns(alarm->node.expires, | |
457 | incr*overrun); | |
458 | ||
2456e855 | 459 | if (alarm->node.expires > now) |
dce75a8c JS |
460 | return overrun; |
461 | /* | |
462 | * This (and the ktime_add() below) is the | |
463 | * correction for exact: | |
464 | */ | |
465 | overrun++; | |
466 | } | |
467 | ||
f4781e76 | 468 | alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); |
dce75a8c JS |
469 | return overrun; |
470 | } | |
11682a41 | 471 | EXPORT_SYMBOL_GPL(alarm_forward); |
dce75a8c | 472 | |
6cffe00f TP |
473 | u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) |
474 | { | |
475 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
476 | ||
477 | return alarm_forward(alarm, base->gettime(), interval); | |
478 | } | |
11682a41 | 479 | EXPORT_SYMBOL_GPL(alarm_forward_now); |
dce75a8c | 480 | |
d3ba5a9a CH |
481 | #ifdef CONFIG_POSIX_TIMERS |
482 | ||
483 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) | |
484 | { | |
485 | struct alarm_base *base; | |
486 | unsigned long flags; | |
487 | ktime_t delta; | |
488 | ||
489 | switch(type) { | |
490 | case ALARM_REALTIME: | |
491 | base = &alarm_bases[ALARM_REALTIME]; | |
492 | type = ALARM_REALTIME_FREEZER; | |
493 | break; | |
494 | case ALARM_BOOTTIME: | |
495 | base = &alarm_bases[ALARM_BOOTTIME]; | |
496 | type = ALARM_BOOTTIME_FREEZER; | |
497 | break; | |
498 | default: | |
499 | WARN_ONCE(1, "Invalid alarm type: %d\n", type); | |
500 | return; | |
501 | } | |
502 | ||
503 | delta = ktime_sub(absexp, base->gettime()); | |
504 | ||
505 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
506 | if (!freezer_delta || (delta < freezer_delta)) { | |
507 | freezer_delta = delta; | |
508 | freezer_expires = absexp; | |
509 | freezer_alarmtype = type; | |
510 | } | |
511 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
512 | } | |
dce75a8c | 513 | |
180bf812 | 514 | /** |
9a7adcf5 JS |
515 | * clock2alarm - helper that converts from clockid to alarmtypes |
516 | * @clockid: clockid. | |
9a7adcf5 JS |
517 | */ |
518 | static enum alarmtimer_type clock2alarm(clockid_t clockid) | |
519 | { | |
520 | if (clockid == CLOCK_REALTIME_ALARM) | |
521 | return ALARM_REALTIME; | |
522 | if (clockid == CLOCK_BOOTTIME_ALARM) | |
523 | return ALARM_BOOTTIME; | |
524 | return -1; | |
525 | } | |
526 | ||
180bf812 | 527 | /** |
9a7adcf5 JS |
528 | * alarm_handle_timer - Callback for posix timers |
529 | * @alarm: alarm that fired | |
530 | * | |
531 | * Posix timer callback for expired alarm timers. | |
532 | */ | |
4b41308d JS |
533 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
534 | ktime_t now) | |
9a7adcf5 JS |
535 | { |
536 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, | |
f2c45807 | 537 | it.alarm.alarmtimer); |
474e941b | 538 | enum alarmtimer_restart result = ALARMTIMER_NORESTART; |
f2c45807 TG |
539 | unsigned long flags; |
540 | int si_private = 0; | |
474e941b RL |
541 | |
542 | spin_lock_irqsave(&ptr->it_lock, flags); | |
4b41308d | 543 | |
f2c45807 TG |
544 | ptr->it_active = 0; |
545 | if (ptr->it_interval) | |
546 | si_private = ++ptr->it_requeue_pending; | |
547 | ||
548 | if (posix_timer_event(ptr, si_private) && ptr->it_interval) { | |
549 | /* | |
550 | * Handle ignored signals and rearm the timer. This will go | |
551 | * away once we handle ignored signals proper. | |
552 | */ | |
553 | ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval); | |
554 | ++ptr->it_requeue_pending; | |
555 | ptr->it_active = 1; | |
474e941b | 556 | result = ALARMTIMER_RESTART; |
54da23b7 | 557 | } |
474e941b RL |
558 | spin_unlock_irqrestore(&ptr->it_lock, flags); |
559 | ||
560 | return result; | |
9a7adcf5 JS |
561 | } |
562 | ||
b3db80f7 TG |
563 | /** |
564 | * alarm_timer_rearm - Posix timer callback for rearming timer | |
565 | * @timr: Pointer to the posixtimer data struct | |
566 | */ | |
567 | static void alarm_timer_rearm(struct k_itimer *timr) | |
568 | { | |
569 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
570 | ||
571 | timr->it_overrun += alarm_forward_now(alarm, timr->it_interval); | |
572 | alarm_start(alarm, alarm->node.expires); | |
573 | } | |
574 | ||
e7561f16 TG |
575 | /** |
576 | * alarm_timer_forward - Posix timer callback for forwarding timer | |
577 | * @timr: Pointer to the posixtimer data struct | |
578 | * @now: Current time to forward the timer against | |
579 | */ | |
6fec64e1 | 580 | static s64 alarm_timer_forward(struct k_itimer *timr, ktime_t now) |
e7561f16 TG |
581 | { |
582 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
583 | ||
6fec64e1 | 584 | return alarm_forward(alarm, timr->it_interval, now); |
e7561f16 TG |
585 | } |
586 | ||
d653d845 TG |
587 | /** |
588 | * alarm_timer_remaining - Posix timer callback to retrieve remaining time | |
589 | * @timr: Pointer to the posixtimer data struct | |
590 | * @now: Current time to calculate against | |
591 | */ | |
592 | static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now) | |
593 | { | |
594 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
595 | ||
07d7e120 | 596 | return ktime_sub(alarm->node.expires, now); |
d653d845 TG |
597 | } |
598 | ||
e344c9e7 TG |
599 | /** |
600 | * alarm_timer_try_to_cancel - Posix timer callback to cancel a timer | |
601 | * @timr: Pointer to the posixtimer data struct | |
602 | */ | |
603 | static int alarm_timer_try_to_cancel(struct k_itimer *timr) | |
604 | { | |
605 | return alarm_try_to_cancel(&timr->it.alarm.alarmtimer); | |
606 | } | |
607 | ||
ec8f954a TG |
608 | /** |
609 | * alarm_timer_wait_running - Posix timer callback to wait for a timer | |
610 | * @timr: Pointer to the posixtimer data struct | |
611 | * | |
612 | * Called from the core code when timer cancel detected that the callback | |
613 | * is running. @timr is unlocked and rcu read lock is held to prevent it | |
614 | * from being freed. | |
615 | */ | |
616 | static void alarm_timer_wait_running(struct k_itimer *timr) | |
617 | { | |
618 | hrtimer_cancel_wait_running(&timr->it.alarm.alarmtimer.timer); | |
619 | } | |
620 | ||
b3bf6f36 TG |
621 | /** |
622 | * alarm_timer_arm - Posix timer callback to arm a timer | |
623 | * @timr: Pointer to the posixtimer data struct | |
624 | * @expires: The new expiry time | |
625 | * @absolute: Expiry value is absolute time | |
626 | * @sigev_none: Posix timer does not deliver signals | |
627 | */ | |
628 | static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires, | |
629 | bool absolute, bool sigev_none) | |
630 | { | |
631 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
632 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
633 | ||
634 | if (!absolute) | |
635 | expires = ktime_add_safe(expires, base->gettime()); | |
636 | if (sigev_none) | |
637 | alarm->node.expires = expires; | |
638 | else | |
639 | alarm_start(&timr->it.alarm.alarmtimer, expires); | |
640 | } | |
641 | ||
180bf812 | 642 | /** |
9a7adcf5 JS |
643 | * alarm_clock_getres - posix getres interface |
644 | * @which_clock: clockid | |
645 | * @tp: timespec to fill | |
646 | * | |
647 | * Returns the granularity of underlying alarm base clock | |
648 | */ | |
d2e3e0ca | 649 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 | 650 | { |
1c6b39ad | 651 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 652 | return -EINVAL; |
1c6b39ad | 653 | |
056a3cac TG |
654 | tp->tv_sec = 0; |
655 | tp->tv_nsec = hrtimer_resolution; | |
656 | return 0; | |
9a7adcf5 JS |
657 | } |
658 | ||
659 | /** | |
660 | * alarm_clock_get - posix clock_get interface | |
661 | * @which_clock: clockid | |
662 | * @tp: timespec to fill. | |
663 | * | |
664 | * Provides the underlying alarm base time. | |
665 | */ | |
3c9c12f4 | 666 | static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 JS |
667 | { |
668 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; | |
669 | ||
1c6b39ad | 670 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 671 | return -EINVAL; |
1c6b39ad | 672 | |
3c9c12f4 | 673 | *tp = ktime_to_timespec64(base->gettime()); |
9a7adcf5 JS |
674 | return 0; |
675 | } | |
676 | ||
677 | /** | |
678 | * alarm_timer_create - posix timer_create interface | |
679 | * @new_timer: k_itimer pointer to manage | |
680 | * | |
681 | * Initializes the k_itimer structure. | |
682 | */ | |
683 | static int alarm_timer_create(struct k_itimer *new_timer) | |
684 | { | |
685 | enum alarmtimer_type type; | |
9a7adcf5 | 686 | |
1c6b39ad | 687 | if (!alarmtimer_get_rtcdev()) |
f18ddc13 | 688 | return -EOPNOTSUPP; |
1c6b39ad | 689 | |
9a7adcf5 JS |
690 | if (!capable(CAP_WAKE_ALARM)) |
691 | return -EPERM; | |
692 | ||
693 | type = clock2alarm(new_timer->it_clock); | |
9e264762 | 694 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
9a7adcf5 JS |
695 | return 0; |
696 | } | |
697 | ||
9a7adcf5 JS |
698 | /** |
699 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep | |
700 | * @alarm: ptr to alarm that fired | |
701 | * | |
702 | * Wakes up the task that set the alarmtimer | |
703 | */ | |
4b41308d JS |
704 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
705 | ktime_t now) | |
9a7adcf5 JS |
706 | { |
707 | struct task_struct *task = (struct task_struct *)alarm->data; | |
708 | ||
709 | alarm->data = NULL; | |
710 | if (task) | |
711 | wake_up_process(task); | |
4b41308d | 712 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
713 | } |
714 | ||
715 | /** | |
716 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation | |
717 | * @alarm: ptr to alarmtimer | |
718 | * @absexp: absolute expiration time | |
719 | * | |
720 | * Sets the alarm timer and sleeps until it is fired or interrupted. | |
721 | */ | |
15f27ce2 AV |
722 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, |
723 | enum alarmtimer_type type) | |
9a7adcf5 | 724 | { |
edbeda46 | 725 | struct restart_block *restart; |
9a7adcf5 JS |
726 | alarm->data = (void *)current; |
727 | do { | |
728 | set_current_state(TASK_INTERRUPTIBLE); | |
9e264762 | 729 | alarm_start(alarm, absexp); |
9a7adcf5 JS |
730 | if (likely(alarm->data)) |
731 | schedule(); | |
732 | ||
733 | alarm_cancel(alarm); | |
734 | } while (alarm->data && !signal_pending(current)); | |
735 | ||
736 | __set_current_state(TASK_RUNNING); | |
737 | ||
bd031430 TG |
738 | destroy_hrtimer_on_stack(&alarm->timer); |
739 | ||
15f27ce2 | 740 | if (!alarm->data) |
9a7adcf5 | 741 | return 0; |
9a7adcf5 | 742 | |
15f27ce2 AV |
743 | if (freezing(current)) |
744 | alarmtimer_freezerset(absexp, type); | |
edbeda46 AV |
745 | restart = ¤t->restart_block; |
746 | if (restart->nanosleep.type != TT_NONE) { | |
c0edd7c9 | 747 | struct timespec64 rmt; |
15f27ce2 | 748 | ktime_t rem; |
9a7adcf5 | 749 | |
15f27ce2 | 750 | rem = ktime_sub(absexp, alarm_bases[type].gettime()); |
9a7adcf5 | 751 | |
15f27ce2 AV |
752 | if (rem <= 0) |
753 | return 0; | |
c0edd7c9 | 754 | rmt = ktime_to_timespec64(rem); |
15f27ce2 | 755 | |
ce41aaf4 | 756 | return nanosleep_copyout(restart, &rmt); |
15f27ce2 AV |
757 | } |
758 | return -ERESTART_RESTARTBLOCK; | |
9a7adcf5 JS |
759 | } |
760 | ||
bd031430 TG |
761 | static void |
762 | alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type, | |
763 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) | |
764 | { | |
765 | hrtimer_init_on_stack(&alarm->timer, alarm_bases[type].base_clockid, | |
766 | HRTIMER_MODE_ABS); | |
767 | __alarm_init(alarm, type, function); | |
768 | } | |
769 | ||
9a7adcf5 JS |
770 | /** |
771 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep | |
772 | * @restart: ptr to restart block | |
773 | * | |
774 | * Handles restarted clock_nanosleep calls | |
775 | */ | |
776 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) | |
777 | { | |
ab8177bc | 778 | enum alarmtimer_type type = restart->nanosleep.clockid; |
15f27ce2 | 779 | ktime_t exp = restart->nanosleep.expires; |
9a7adcf5 | 780 | struct alarm alarm; |
9a7adcf5 | 781 | |
bd031430 | 782 | alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); |
9a7adcf5 | 783 | |
15f27ce2 | 784 | return alarmtimer_do_nsleep(&alarm, exp, type); |
9a7adcf5 JS |
785 | } |
786 | ||
787 | /** | |
788 | * alarm_timer_nsleep - alarmtimer nanosleep | |
789 | * @which_clock: clockid | |
790 | * @flags: determins abstime or relative | |
791 | * @tsreq: requested sleep time (abs or rel) | |
792 | * @rmtp: remaining sleep time saved | |
793 | * | |
794 | * Handles clock_nanosleep calls against _ALARM clockids | |
795 | */ | |
796 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, | |
938e7cf2 | 797 | const struct timespec64 *tsreq) |
9a7adcf5 JS |
798 | { |
799 | enum alarmtimer_type type = clock2alarm(which_clock); | |
15f27ce2 | 800 | struct restart_block *restart = ¤t->restart_block; |
9a7adcf5 JS |
801 | struct alarm alarm; |
802 | ktime_t exp; | |
803 | int ret = 0; | |
9a7adcf5 | 804 | |
1c6b39ad | 805 | if (!alarmtimer_get_rtcdev()) |
f18ddc13 | 806 | return -EOPNOTSUPP; |
1c6b39ad | 807 | |
16927776 JS |
808 | if (flags & ~TIMER_ABSTIME) |
809 | return -EINVAL; | |
810 | ||
9a7adcf5 JS |
811 | if (!capable(CAP_WAKE_ALARM)) |
812 | return -EPERM; | |
813 | ||
bd031430 | 814 | alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); |
9a7adcf5 | 815 | |
ad196384 | 816 | exp = timespec64_to_ktime(*tsreq); |
9a7adcf5 JS |
817 | /* Convert (if necessary) to absolute time */ |
818 | if (flags != TIMER_ABSTIME) { | |
819 | ktime_t now = alarm_bases[type].gettime(); | |
5f936e19 TG |
820 | |
821 | exp = ktime_add_safe(now, exp); | |
9a7adcf5 JS |
822 | } |
823 | ||
15f27ce2 AV |
824 | ret = alarmtimer_do_nsleep(&alarm, exp, type); |
825 | if (ret != -ERESTART_RESTARTBLOCK) | |
826 | return ret; | |
9a7adcf5 JS |
827 | |
828 | /* abs timers don't set remaining time or restart */ | |
15f27ce2 AV |
829 | if (flags == TIMER_ABSTIME) |
830 | return -ERESTARTNOHAND; | |
9a7adcf5 | 831 | |
9a7adcf5 | 832 | restart->fn = alarm_timer_nsleep_restart; |
ab8177bc | 833 | restart->nanosleep.clockid = type; |
2456e855 | 834 | restart->nanosleep.expires = exp; |
9a7adcf5 JS |
835 | return ret; |
836 | } | |
ff3ead96 | 837 | |
d3ba5a9a | 838 | const struct k_clock alarm_clock = { |
d653d845 TG |
839 | .clock_getres = alarm_clock_getres, |
840 | .clock_get = alarm_clock_get, | |
841 | .timer_create = alarm_timer_create, | |
f2c45807 TG |
842 | .timer_set = common_timer_set, |
843 | .timer_del = common_timer_del, | |
844 | .timer_get = common_timer_get, | |
b3bf6f36 | 845 | .timer_arm = alarm_timer_arm, |
d653d845 TG |
846 | .timer_rearm = alarm_timer_rearm, |
847 | .timer_forward = alarm_timer_forward, | |
848 | .timer_remaining = alarm_timer_remaining, | |
e344c9e7 | 849 | .timer_try_to_cancel = alarm_timer_try_to_cancel, |
ec8f954a | 850 | .timer_wait_running = alarm_timer_wait_running, |
d653d845 | 851 | .nsleep = alarm_timer_nsleep, |
d3ba5a9a CH |
852 | }; |
853 | #endif /* CONFIG_POSIX_TIMERS */ | |
854 | ||
ff3ead96 JS |
855 | |
856 | /* Suspend hook structures */ | |
857 | static const struct dev_pm_ops alarmtimer_pm_ops = { | |
858 | .suspend = alarmtimer_suspend, | |
a0e3213f | 859 | .resume = alarmtimer_resume, |
ff3ead96 JS |
860 | }; |
861 | ||
862 | static struct platform_driver alarmtimer_driver = { | |
863 | .driver = { | |
864 | .name = "alarmtimer", | |
865 | .pm = &alarmtimer_pm_ops, | |
866 | } | |
867 | }; | |
868 | ||
869 | /** | |
870 | * alarmtimer_init - Initialize alarm timer code | |
871 | * | |
872 | * This function initializes the alarm bases and registers | |
873 | * the posix clock ids. | |
874 | */ | |
875 | static int __init alarmtimer_init(void) | |
876 | { | |
4523f6ad | 877 | struct platform_device *pdev; |
ff3ead96 JS |
878 | int error = 0; |
879 | int i; | |
9a7adcf5 | 880 | |
c5e14e76 | 881 | alarmtimer_rtc_timer_init(); |
ad30dfa9 | 882 | |
ff3ead96 JS |
883 | /* Initialize alarm bases */ |
884 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; | |
885 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; | |
886 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; | |
887 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; | |
888 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
889 | timerqueue_init_head(&alarm_bases[i].timerqueue); | |
890 | spin_lock_init(&alarm_bases[i].lock); | |
ff3ead96 | 891 | } |
8bc0dafb | 892 | |
4523f6ad TG |
893 | error = alarmtimer_rtc_interface_setup(); |
894 | if (error) | |
895 | return error; | |
896 | ||
ff3ead96 | 897 | error = platform_driver_register(&alarmtimer_driver); |
4523f6ad TG |
898 | if (error) |
899 | goto out_if; | |
ff3ead96 | 900 | |
4523f6ad TG |
901 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
902 | if (IS_ERR(pdev)) { | |
903 | error = PTR_ERR(pdev); | |
904 | goto out_drv; | |
905 | } | |
906 | return 0; | |
907 | ||
908 | out_drv: | |
909 | platform_driver_unregister(&alarmtimer_driver); | |
910 | out_if: | |
911 | alarmtimer_rtc_interface_remove(); | |
ff3ead96 JS |
912 | return error; |
913 | } | |
914 | device_initcall(alarmtimer_init); |