alarmtimer: Lock k_itimer during timer callback

[pandora-kernel.git] / kernel / time / alarmtimer.c

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index c436e79..7eaf162 100644 (file)
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -195,7 +195,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
                struct alarm *alarm;
                ktime_t expired = next->expires;
 
-               if (expired.tv64 >= now.tv64)
+               if (expired.tv64 > now.tv64)
                        break;
 
                alarm = container_of(next, struct alarm, node);
@@ -226,6 +226,12 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
 
 }
 
+ktime_t alarm_expires_remaining(const struct alarm *alarm)
+{
+       struct alarm_base *base = &alarm_bases[alarm->type];
+       return ktime_sub(alarm->node.expires, base->gettime());
+}
+
 #ifdef CONFIG_RTC_CLASS
 /**
  * alarmtimer_suspend - Suspend time callback
@@ -442,18 +448,26 @@ 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);
-       if (posix_timer_event(ptr, 0) != 0)
-               ptr->it_overrun++;
+       enum alarmtimer_restart result = ALARMTIMER_NORESTART;
+
+       spin_lock_irqsave(&ptr->it_lock, flags);
+       if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
+               if (posix_timer_event(ptr, 0) != 0)
+                       ptr->it_overrun++;
+       }
 
        /* Re-add periodic timers */
        if (ptr->it.alarm.interval.tv64) {
                ptr->it_overrun += alarm_forward(alarm, now,
                                                ptr->it.alarm.interval);
-               return ALARMTIMER_RESTART;
+               result = ALARMTIMER_RESTART;
        }
-       return ALARMTIMER_NORESTART;
+       spin_unlock_irqrestore(&ptr->it_lock, flags);
+
+       return result;
 }
 
 /**
@@ -468,7 +482,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp)
        clockid_t baseid = alarm_bases[clock2alarm(which_clock)].base_clockid;
 
        if (!alarmtimer_get_rtcdev())
-               return -ENOTSUPP;
+               return -EINVAL;
 
        return hrtimer_get_res(baseid, tp);
 }
@@ -485,7 +499,7 @@ static int alarm_clock_get(clockid_t which_clock, struct timespec *tp)
        struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
 
        if (!alarmtimer_get_rtcdev())
-               return -ENOTSUPP;
+               return -EINVAL;
 
        *tp = ktime_to_timespec(base->gettime());
        return 0;
@@ -519,18 +533,22 @@ static int alarm_timer_create(struct k_itimer *new_timer)
  * @new_timer: k_itimer pointer
  * @cur_setting: itimerspec data to fill
  *
- * Copies the itimerspec data out from the k_itimer
+ * Copies out the current itimerspec data
  */
 static void alarm_timer_get(struct k_itimer *timr,
                                struct itimerspec *cur_setting)
 {
-       memset(cur_setting, 0, sizeof(struct itimerspec));
+       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_timespec(relative_expiry_time);
+       } else {
+               cur_setting->it_value.tv_sec = 0;
+               cur_setting->it_value.tv_nsec = 0;
+       }
 
-       cur_setting->it_interval =
-                       ktime_to_timespec(timr->it.alarm.interval);
-       cur_setting->it_value =
-               ktime_to_timespec(timr->it.alarm.alarmtimer.node.expires);
-       return;
+       cur_setting->it_interval = ktime_to_timespec(timr->it.alarm.interval);
 }
 
 /**
@@ -563,9 +581,14 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
                                struct itimerspec *new_setting,
                                struct itimerspec *old_setting)
 {
+       ktime_t exp;
+
        if (!rtcdev)
                return -ENOTSUPP;
 
+       if (flags & ~TIMER_ABSTIME)
+               return -EINVAL;
+
        if (old_setting)
                alarm_timer_get(timr, old_setting);
 
@@ -575,8 +598,16 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
 
        /* start the timer */
        timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval);
-       alarm_start(&timr->it.alarm.alarmtimer,
-                       timespec_to_ktime(new_setting->it_value));
+       exp = timespec_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(now, exp);
+       }
+
+       alarm_start(&timr->it.alarm.alarmtimer, exp);
        return 0;
 }
 
@@ -708,6 +739,9 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
        if (!alarmtimer_get_rtcdev())
                return -ENOTSUPP;
 
+       if (flags & ~TIMER_ABSTIME)
+               return -EINVAL;
+
        if (!capable(CAP_WAKE_ALARM))
                return -EPERM;