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-rw-r--r--kernel/time/alarmtimer.c381
1 files changed, 161 insertions, 220 deletions
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index ee2f4202d82a..c991cf212c6d 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -27,6 +27,9 @@
#include <linux/posix-timers.h>
#include <linux/workqueue.h>
#include <linux/freezer.h>
+#include <linux/compat.h>
+
+#include "posix-timers.h"
#define CREATE_TRACE_POINTS
#include <trace/events/alarmtimer.h>
@@ -45,11 +48,13 @@ static struct alarm_base {
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
+#if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS)
/* freezer information to handle clock_nanosleep triggered wakeups */
static enum alarmtimer_type freezer_alarmtype;
static ktime_t freezer_expires;
static ktime_t freezer_delta;
static DEFINE_SPINLOCK(freezer_delta_lock);
+#endif
static struct wakeup_source *ws;
@@ -307,38 +312,6 @@ static int alarmtimer_resume(struct device *dev)
}
#endif
-static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
-{
- struct alarm_base *base;
- unsigned long flags;
- ktime_t delta;
-
- switch(type) {
- case ALARM_REALTIME:
- base = &alarm_bases[ALARM_REALTIME];
- type = ALARM_REALTIME_FREEZER;
- break;
- case ALARM_BOOTTIME:
- base = &alarm_bases[ALARM_BOOTTIME];
- type = ALARM_BOOTTIME_FREEZER;
- break;
- default:
- WARN_ONCE(1, "Invalid alarm type: %d\n", type);
- return;
- }
-
- delta = ktime_sub(absexp, base->gettime());
-
- spin_lock_irqsave(&freezer_delta_lock, flags);
- if (!freezer_delta || (delta < freezer_delta)) {
- freezer_delta = delta;
- freezer_expires = absexp;
- freezer_alarmtype = type;
- }
- spin_unlock_irqrestore(&freezer_delta_lock, flags);
-}
-
-
/**
* alarm_init - Initialize an alarm structure
* @alarm: ptr to alarm to be initialized
@@ -488,6 +461,38 @@ u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
}
EXPORT_SYMBOL_GPL(alarm_forward_now);
+#ifdef CONFIG_POSIX_TIMERS
+
+static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
+{
+ struct alarm_base *base;
+ unsigned long flags;
+ ktime_t delta;
+
+ switch(type) {
+ case ALARM_REALTIME:
+ base = &alarm_bases[ALARM_REALTIME];
+ type = ALARM_REALTIME_FREEZER;
+ break;
+ case ALARM_BOOTTIME:
+ base = &alarm_bases[ALARM_BOOTTIME];
+ type = ALARM_BOOTTIME_FREEZER;
+ break;
+ default:
+ WARN_ONCE(1, "Invalid alarm type: %d\n", type);
+ return;
+ }
+
+ delta = ktime_sub(absexp, base->gettime());
+
+ spin_lock_irqsave(&freezer_delta_lock, flags);
+ if (!freezer_delta || (delta < freezer_delta)) {
+ freezer_delta = delta;
+ freezer_expires = absexp;
+ freezer_alarmtype = type;
+ }
+ spin_unlock_irqrestore(&freezer_delta_lock, flags);
+}
/**
* clock2alarm - helper that converts from clockid to alarmtypes
@@ -511,22 +516,26 @@ static enum alarmtimer_type clock2alarm(clockid_t clockid)
static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
ktime_t now)
{
- unsigned long flags;
struct k_itimer *ptr = container_of(alarm, struct k_itimer,
- it.alarm.alarmtimer);
+ it.alarm.alarmtimer);
enum alarmtimer_restart result = ALARMTIMER_NORESTART;
+ unsigned long flags;
+ int si_private = 0;
spin_lock_irqsave(&ptr->it_lock, flags);
- if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
- if (IS_ENABLED(CONFIG_POSIX_TIMERS) &&
- posix_timer_event(ptr, 0) != 0)
- ptr->it_overrun++;
- }
- /* Re-add periodic timers */
- if (ptr->it.alarm.interval) {
- ptr->it_overrun += alarm_forward(alarm, now,
- ptr->it.alarm.interval);
+ ptr->it_active = 0;
+ if (ptr->it_interval)
+ si_private = ++ptr->it_requeue_pending;
+
+ if (posix_timer_event(ptr, si_private) && ptr->it_interval) {
+ /*
+ * Handle ignored signals and rearm the timer. This will go
+ * away once we handle ignored signals proper.
+ */
+ ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval);
+ ++ptr->it_requeue_pending;
+ ptr->it_active = 1;
result = ALARMTIMER_RESTART;
}
spin_unlock_irqrestore(&ptr->it_lock, flags);
@@ -535,6 +544,72 @@ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
}
/**
+ * alarm_timer_rearm - Posix timer callback for rearming timer
+ * @timr: Pointer to the posixtimer data struct
+ */
+static void alarm_timer_rearm(struct k_itimer *timr)
+{
+ struct alarm *alarm = &timr->it.alarm.alarmtimer;
+
+ timr->it_overrun += alarm_forward_now(alarm, timr->it_interval);
+ alarm_start(alarm, alarm->node.expires);
+}
+
+/**
+ * alarm_timer_forward - Posix timer callback for forwarding timer
+ * @timr: Pointer to the posixtimer data struct
+ * @now: Current time to forward the timer against
+ */
+static int alarm_timer_forward(struct k_itimer *timr, ktime_t now)
+{
+ struct alarm *alarm = &timr->it.alarm.alarmtimer;
+
+ return (int) alarm_forward(alarm, timr->it_interval, now);
+}
+
+/**
+ * alarm_timer_remaining - Posix timer callback to retrieve remaining time
+ * @timr: Pointer to the posixtimer data struct
+ * @now: Current time to calculate against
+ */
+static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now)
+{
+ struct alarm *alarm = &timr->it.alarm.alarmtimer;
+
+ return ktime_sub(now, alarm->node.expires);
+}
+
+/**
+ * alarm_timer_try_to_cancel - Posix timer callback to cancel a timer
+ * @timr: Pointer to the posixtimer data struct
+ */
+static int alarm_timer_try_to_cancel(struct k_itimer *timr)
+{
+ return alarm_try_to_cancel(&timr->it.alarm.alarmtimer);
+}
+
+/**
+ * alarm_timer_arm - Posix timer callback to arm a timer
+ * @timr: Pointer to the posixtimer data struct
+ * @expires: The new expiry time
+ * @absolute: Expiry value is absolute time
+ * @sigev_none: Posix timer does not deliver signals
+ */
+static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires,
+ bool absolute, bool sigev_none)
+{
+ struct alarm *alarm = &timr->it.alarm.alarmtimer;
+ struct alarm_base *base = &alarm_bases[alarm->type];
+
+ if (!absolute)
+ expires = ktime_add_safe(expires, base->gettime());
+ if (sigev_none)
+ alarm->node.expires = expires;
+ else
+ alarm_start(&timr->it.alarm.alarmtimer, expires);
+}
+
+/**
* alarm_clock_getres - posix getres interface
* @which_clock: clockid
* @tp: timespec to fill
@@ -591,97 +666,6 @@ static int alarm_timer_create(struct k_itimer *new_timer)
}
/**
- * alarm_timer_get - posix timer_get interface
- * @new_timer: k_itimer pointer
- * @cur_setting: itimerspec data to fill
- *
- * Copies out the current itimerspec data
- */
-static void alarm_timer_get(struct k_itimer *timr,
- struct itimerspec64 *cur_setting)
-{
- ktime_t relative_expiry_time =
- alarm_expires_remaining(&(timr->it.alarm.alarmtimer));
-
- if (ktime_to_ns(relative_expiry_time) > 0) {
- cur_setting->it_value = ktime_to_timespec64(relative_expiry_time);
- } else {
- cur_setting->it_value.tv_sec = 0;
- cur_setting->it_value.tv_nsec = 0;
- }
-
- cur_setting->it_interval = ktime_to_timespec64(timr->it.alarm.interval);
-}
-
-/**
- * alarm_timer_del - posix timer_del interface
- * @timr: k_itimer pointer to be deleted
- *
- * Cancels any programmed alarms for the given timer.
- */
-static int alarm_timer_del(struct k_itimer *timr)
-{
- if (!rtcdev)
- return -ENOTSUPP;
-
- if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0)
- return TIMER_RETRY;
-
- return 0;
-}
-
-/**
- * alarm_timer_set - posix timer_set interface
- * @timr: k_itimer pointer to be deleted
- * @flags: timer flags
- * @new_setting: itimerspec to be used
- * @old_setting: itimerspec being replaced
- *
- * Sets the timer to new_setting, and starts the timer.
- */
-static int alarm_timer_set(struct k_itimer *timr, int flags,
- struct itimerspec64 *new_setting,
- struct itimerspec64 *old_setting)
-{
- ktime_t exp;
-
- if (!rtcdev)
- return -ENOTSUPP;
-
- if (flags & ~TIMER_ABSTIME)
- return -EINVAL;
-
- if (old_setting)
- alarm_timer_get(timr, old_setting);
-
- /* If the timer was already set, cancel it */
- if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0)
- return TIMER_RETRY;
-
- /* start the timer */
- timr->it.alarm.interval = timespec64_to_ktime(new_setting->it_interval);
-
- /*
- * Rate limit to the tick as a hot fix to prevent DOS. Will be
- * mopped up later.
- */
- if (timr->it.alarm.interval < TICK_NSEC)
- timr->it.alarm.interval = TICK_NSEC;
-
- exp = timespec64_to_ktime(new_setting->it_value);
- /* Convert (if necessary) to absolute time */
- if (flags != TIMER_ABSTIME) {
- ktime_t now;
-
- now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime();
- exp = ktime_add_safe(now, exp);
- }
-
- alarm_start(&timr->it.alarm.alarmtimer, exp);
- return 0;
-}
-
-/**
* alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep
* @alarm: ptr to alarm that fired
*
@@ -705,8 +689,10 @@ static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm,
*
* Sets the alarm timer and sleeps until it is fired or interrupted.
*/
-static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp)
+static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
+ enum alarmtimer_type type)
{
+ struct restart_block *restart;
alarm->data = (void *)current;
do {
set_current_state(TASK_INTERRUPTIBLE);
@@ -719,36 +705,25 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp)
__set_current_state(TASK_RUNNING);
- return (alarm->data == NULL);
-}
-
-
-/**
- * update_rmtp - Update remaining timespec value
- * @exp: expiration time
- * @type: timer type
- * @rmtp: user pointer to remaining timepsec value
- *
- * Helper function that fills in rmtp value with time between
- * now and the exp value
- */
-static int update_rmtp(ktime_t exp, enum alarmtimer_type type,
- struct timespec __user *rmtp)
-{
- struct timespec rmt;
- ktime_t rem;
-
- rem = ktime_sub(exp, alarm_bases[type].gettime());
-
- if (rem <= 0)
+ if (!alarm->data)
return 0;
- rmt = ktime_to_timespec(rem);
- if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
- return -EFAULT;
+ if (freezing(current))
+ alarmtimer_freezerset(absexp, type);
+ restart = &current->restart_block;
+ if (restart->nanosleep.type != TT_NONE) {
+ struct timespec rmt;
+ ktime_t rem;
+
+ rem = ktime_sub(absexp, alarm_bases[type].gettime());
- return 1;
+ if (rem <= 0)
+ return 0;
+ rmt = ktime_to_timespec(rem);
+ return nanosleep_copyout(restart, &rmt);
+ }
+ return -ERESTART_RESTARTBLOCK;
}
/**
@@ -760,32 +735,12 @@ static int update_rmtp(ktime_t exp, enum alarmtimer_type type,
static long __sched alarm_timer_nsleep_restart(struct restart_block *restart)
{
enum alarmtimer_type type = restart->nanosleep.clockid;
- ktime_t exp;
- struct timespec __user *rmtp;
+ ktime_t exp = restart->nanosleep.expires;
struct alarm alarm;
- int ret = 0;
- exp = restart->nanosleep.expires;
alarm_init(&alarm, type, alarmtimer_nsleep_wakeup);
- if (alarmtimer_do_nsleep(&alarm, exp))
- goto out;
-
- if (freezing(current))
- alarmtimer_freezerset(exp, type);
-
- rmtp = restart->nanosleep.rmtp;
- if (rmtp) {
- ret = update_rmtp(exp, type, rmtp);
- if (ret <= 0)
- goto out;
- }
-
-
- /* The other values in restart are already filled in */
- ret = -ERESTART_RESTARTBLOCK;
-out:
- return ret;
+ return alarmtimer_do_nsleep(&alarm, exp, type);
}
/**
@@ -798,11 +753,10 @@ out:
* Handles clock_nanosleep calls against _ALARM clockids
*/
static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
- struct timespec64 *tsreq,
- struct timespec __user *rmtp)
+ const struct timespec64 *tsreq)
{
enum alarmtimer_type type = clock2alarm(which_clock);
- struct restart_block *restart;
+ struct restart_block *restart = &current->restart_block;
struct alarm alarm;
ktime_t exp;
int ret = 0;
@@ -825,35 +779,36 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
exp = ktime_add(now, exp);
}
- if (alarmtimer_do_nsleep(&alarm, exp))
- goto out;
-
- if (freezing(current))
- alarmtimer_freezerset(exp, type);
+ ret = alarmtimer_do_nsleep(&alarm, exp, type);
+ if (ret != -ERESTART_RESTARTBLOCK)
+ return ret;
/* abs timers don't set remaining time or restart */
- if (flags == TIMER_ABSTIME) {
- ret = -ERESTARTNOHAND;
- goto out;
- }
+ if (flags == TIMER_ABSTIME)
+ return -ERESTARTNOHAND;
- if (rmtp) {
- ret = update_rmtp(exp, type, rmtp);
- if (ret <= 0)
- goto out;
- }
-
- restart = &current->restart_block;
restart->fn = alarm_timer_nsleep_restart;
restart->nanosleep.clockid = type;
restart->nanosleep.expires = exp;
- restart->nanosleep.rmtp = rmtp;
- ret = -ERESTART_RESTARTBLOCK;
-
-out:
return ret;
}
+const struct k_clock alarm_clock = {
+ .clock_getres = alarm_clock_getres,
+ .clock_get = alarm_clock_get,
+ .timer_create = alarm_timer_create,
+ .timer_set = common_timer_set,
+ .timer_del = common_timer_del,
+ .timer_get = common_timer_get,
+ .timer_arm = alarm_timer_arm,
+ .timer_rearm = alarm_timer_rearm,
+ .timer_forward = alarm_timer_forward,
+ .timer_remaining = alarm_timer_remaining,
+ .timer_try_to_cancel = alarm_timer_try_to_cancel,
+ .nsleep = alarm_timer_nsleep,
+};
+#endif /* CONFIG_POSIX_TIMERS */
+
/* Suspend hook structures */
static const struct dev_pm_ops alarmtimer_pm_ops = {
@@ -879,23 +834,9 @@ static int __init alarmtimer_init(void)
struct platform_device *pdev;
int error = 0;
int i;
- struct k_clock alarm_clock = {
- .clock_getres = alarm_clock_getres,
- .clock_get = alarm_clock_get,
- .timer_create = alarm_timer_create,
- .timer_set = alarm_timer_set,
- .timer_del = alarm_timer_del,
- .timer_get = alarm_timer_get,
- .nsleep = alarm_timer_nsleep,
- };
alarmtimer_rtc_timer_init();
- if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
- posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock);
- posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock);
- }
-
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real;