1 files changed, 77 insertions, 104 deletions

diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 5131e5471169..887c63787de6 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -116,7 +116,7 @@ static DEFINE_SPINLOCK(idr_lock);
  *          must supply functions here, even if the function just returns
  *          ENOSYS.  The standard POSIX timer management code assumes the
  *          following: 1.) The k_itimer struct (sched.h) is used for the
- *          timer.  2.) The list, it_lock, it_clock, it_id and it_process
+ *          timer.  2.) The list, it_lock, it_clock, it_id and it_pid
  *          fields are not modified by timer code.
  *
  *          At this time all functions EXCEPT clock_nanosleep can be
@@ -197,6 +197,11 @@ static int common_timer_create(struct k_itimer *new_timer)
         return 0;
 }
 
+static int no_timer_create(struct k_itimer *new_timer)
+{
+        return -EOPNOTSUPP;
+}
+
 /*
  * Return nonzero if we know a priori this clockid_t value is bogus.
  */
@@ -223,6 +228,15 @@ static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
 }
 
 /*
+ * Get monotonic time for posix timers
+ */
+static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
+{
+        getrawmonotonic(tp);
+        return 0;
+}
+
+/*
  * Initialize everything, well, just everything in Posix clocks/timers ;)
  */
 static __init int init_posix_timers(void)
@@ -235,9 +249,16 @@ static __init int init_posix_timers(void)
                 .clock_get = posix_ktime_get_ts,
                 .clock_set = do_posix_clock_nosettime,
         };
+        struct k_clock clock_monotonic_raw = {
+                .clock_getres = hrtimer_get_res,
+                .clock_get = posix_get_monotonic_raw,
+                .clock_set = do_posix_clock_nosettime,
+                .timer_create = no_timer_create,
+        };
 
         register_posix_clock(CLOCK_REALTIME, &clock_realtime);
         register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
+        register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
 
         posix_timers_cache = kmem_cache_create("posix_timers_cache",
                                         sizeof (struct k_itimer), 0, SLAB_PANIC,
@@ -298,6 +319,8 @@ void do_schedule_next_timer(struct siginfo *info)
 
 int posix_timer_event(struct k_itimer *timr, int si_private)
 {
+        struct task_struct *task;
+        int shared, ret = -1;
         /*
          * FIXME: if ->sigq is queued we can race with
          * dequeue_signal()->do_schedule_next_timer().
@@ -311,25 +334,15 @@ int posix_timer_event(struct k_itimer *timr, int si_private)
          */
         timr->sigq->info.si_sys_private = si_private;
 
-        timr->sigq->info.si_signo = timr->it_sigev_signo;
-        timr->sigq->info.si_code = SI_TIMER;
-        timr->sigq->info.si_tid = timr->it_id;
-        timr->sigq->info.si_value = timr->it_sigev_value;
-
-        if (timr->it_sigev_notify & SIGEV_THREAD_ID) {
-                struct task_struct *leader;
-                int ret = send_sigqueue(timr->sigq, timr->it_process, 0);
-
-                if (likely(ret >= 0))
-                        return ret;
-
-                timr->it_sigev_notify = SIGEV_SIGNAL;
-                leader = timr->it_process->group_leader;
-                put_task_struct(timr->it_process);
-                timr->it_process = leader;
+        rcu_read_lock();
+        task = pid_task(timr->it_pid, PIDTYPE_PID);
+        if (task) {
+                shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
+                ret = send_sigqueue(timr->sigq, task, shared);
         }
-
-        return send_sigqueue(timr->sigq, timr->it_process, 1);
+        rcu_read_unlock();
+        /* If we failed to send the signal the timer stops. */
+        return ret > 0;
 }
 EXPORT_SYMBOL_GPL(posix_timer_event);
 
@@ -404,7 +417,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
         return ret;
 }
 
-static struct task_struct * good_sigevent(sigevent_t * event)
+static struct pid *good_sigevent(sigevent_t * event)
 {
         struct task_struct *rtn = current->group_leader;
 
@@ -418,7 +431,7 @@ static struct task_struct * good_sigevent(sigevent_t * event)
             ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
                 return NULL;
 
-        return rtn;
+        return task_pid(rtn);
 }
 
 void register_posix_clock(const clockid_t clock_id, struct k_clock *new_clock)
@@ -457,6 +470,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
                 idr_remove(&posix_timers_id, tmr->it_id);
                 spin_unlock_irqrestore(&idr_lock, flags);
         }
+        put_pid(tmr->it_pid);
         sigqueue_free(tmr->sigq);
         kmem_cache_free(posix_timers_cache, tmr);
 }
@@ -468,11 +482,8 @@ sys_timer_create(const clockid_t which_clock,
                  struct sigevent __user *timer_event_spec,
                  timer_t __user * created_timer_id)
 {
-        int error = 0;
-        struct k_itimer *new_timer = NULL;
-        int new_timer_id;
-        struct task_struct *process = NULL;
-        unsigned long flags;
+        struct k_itimer *new_timer;
+        int error, new_timer_id;
         sigevent_t event;
         int it_id_set = IT_ID_NOT_SET;
 
@@ -490,12 +501,11 @@ sys_timer_create(const clockid_t which_clock,
                 goto out;
         }
         spin_lock_irq(&idr_lock);
-        error = idr_get_new(&posix_timers_id, (void *) new_timer,
-                            &new_timer_id);
+        error = idr_get_new(&posix_timers_id, new_timer, &new_timer_id);
         spin_unlock_irq(&idr_lock);
-        if (error == -EAGAIN)
-                goto retry;
-        else if (error) {
+        if (error) {
+                if (error == -EAGAIN)
+                        goto retry;
                 /*
                  * Weird looking, but we return EAGAIN if the IDR is
                  * full (proper POSIX return value for this)
@@ -526,67 +536,40 @@ sys_timer_create(const clockid_t which_clock,
                         error = -EFAULT;
                         goto out;
                 }
-                new_timer->it_sigev_notify = event.sigev_notify;
-                new_timer->it_sigev_signo = event.sigev_signo;
-                new_timer->it_sigev_value = event.sigev_value;
-
-                read_lock(&tasklist_lock);
-                if ((process = good_sigevent(&event))) {
-                        /*
-                         * We may be setting up this process for another
-                         * thread.  It may be exiting.  To catch this
-                         * case the we check the PF_EXITING flag.  If
-                         * the flag is not set, the siglock will catch
-                         * him before it is too late (in exit_itimers).
-                         *
-                         * The exec case is a bit more invloved but easy
-                         * to code.  If the process is in our thread
-                         * group (and it must be or we would not allow
-                         * it here) and is doing an exec, it will cause
-                         * us to be killed.  In this case it will wait
-                         * for us to die which means we can finish this
-                         * linkage with our last gasp. I.e. no code :)
-                         */
-                        spin_lock_irqsave(&process->sighand->siglock, flags);
-                        if (!(process->flags & PF_EXITING)) {
-                                new_timer->it_process = process;
-                                list_add(&new_timer->list,
-                                         &process->signal->posix_timers);
-                                if (new_timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
-                                        get_task_struct(process);
-                                spin_unlock_irqrestore(&process->sighand->siglock, flags);
-                        } else {
-                                spin_unlock_irqrestore(&process->sighand->siglock, flags);
-                                process = NULL;
-                        }
-                }
-                read_unlock(&tasklist_lock);
-                if (!process) {
+                rcu_read_lock();
+                new_timer->it_pid = get_pid(good_sigevent(&event));
+                rcu_read_unlock();
+                if (!new_timer->it_pid) {
                         error = -EINVAL;
                         goto out;
                 }
         } else {
-                new_timer->it_sigev_notify = SIGEV_SIGNAL;
-                new_timer->it_sigev_signo = SIGALRM;
-                new_timer->it_sigev_value.sival_int = new_timer->it_id;
-                process = current->group_leader;
-                spin_lock_irqsave(&process->sighand->siglock, flags);
-                new_timer->it_process = process;
-                list_add(&new_timer->list, &process->signal->posix_timers);
-                spin_unlock_irqrestore(&process->sighand->siglock, flags);
+                event.sigev_notify = SIGEV_SIGNAL;
+                event.sigev_signo = SIGALRM;
+                event.sigev_value.sival_int = new_timer->it_id;
+                new_timer->it_pid = get_pid(task_tgid(current));
         }
 
+        new_timer->it_sigev_notify     = event.sigev_notify;
+        new_timer->sigq->info.si_signo = event.sigev_signo;
+        new_timer->sigq->info.si_value = event.sigev_value;
+        new_timer->sigq->info.si_tid   = new_timer->it_id;
+        new_timer->sigq->info.si_code  = SI_TIMER;
+
+        spin_lock_irq(&current->sighand->siglock);
+        new_timer->it_signal = current->signal;
+        list_add(&new_timer->list, &current->signal->posix_timers);
+        spin_unlock_irq(&current->sighand->siglock);
+
+        return 0;
         /*
          * In the case of the timer belonging to another task, after
          * the task is unlocked, the timer is owned by the other task
          * and may cease to exist at any time.  Don't use or modify
          * new_timer after the unlock call.
          */
-
 out:
-        if (error)
-                release_posix_timer(new_timer, it_id_set);
-
+        release_posix_timer(new_timer, it_id_set);
         return error;
 }
 
@@ -597,7 +580,7 @@ out:
  * the find to the timer lock.  To avoid a dead lock, the timer id MUST
  * be release with out holding the timer lock.
  */
-static struct k_itimer * lock_timer(timer_t timer_id, unsigned long *flags)
+static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags)
 {
         struct k_itimer *timr;
         /*
@@ -605,23 +588,19 @@ static struct k_itimer * lock_timer(timer_t timer_id, unsigned long *flags)
          * flags part over to the timer lock.  Must not let interrupts in
          * while we are moving the lock.
          */
-
         spin_lock_irqsave(&idr_lock, *flags);
-        timr = (struct k_itimer *) idr_find(&posix_timers_id, (int) timer_id);
+        timr = idr_find(&posix_timers_id, (int)timer_id);
         if (timr) {
                 spin_lock(&timr->it_lock);
-
-                if ((timr->it_id != timer_id) || !(timr->it_process) ||
-                                !same_thread_group(timr->it_process, current)) {
-                        spin_unlock(&timr->it_lock);
-                        spin_unlock_irqrestore(&idr_lock, *flags);
-                        timr = NULL;
-                } else
+                if (timr->it_signal == current->signal) {
                         spin_unlock(&idr_lock);
-        } else
-                spin_unlock_irqrestore(&idr_lock, *flags);
+                        return timr;
+                }
+                spin_unlock(&timr->it_lock);
+        }
+        spin_unlock_irqrestore(&idr_lock, *flags);
 
-        return timr;
+        return NULL;
 }
 
 /*
@@ -668,7 +647,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
             (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
                 timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
 
-        remaining = ktime_sub(timer->expires, now);
+        remaining = ktime_sub(hrtimer_get_expires(timer), now);
         /* Return 0 only, when the timer is expired and not pending */
         if (remaining.tv64 <= 0) {
                 /*
@@ -762,7 +741,7 @@ common_timer_set(struct k_itimer *timr, int flags,
         hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
         timr->it.real.timer.function = posix_timer_fn;
 
-        timer->expires = timespec_to_ktime(new_setting->it_value);
+        hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
 
         /* Convert interval */
         timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
@@ -771,14 +750,12 @@ common_timer_set(struct k_itimer *timr, int flags,
         if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
                 /* Setup correct expiry time for relative timers */
                 if (mode == HRTIMER_MODE_REL) {
-                        timer->expires =
-                                ktime_add_safe(timer->expires,
-                                               timer->base->get_time());
+                        hrtimer_add_expires(timer, timer->base->get_time());
                 }
                 return 0;
         }
 
-        hrtimer_start(timer, timer->expires, mode);
+        hrtimer_start_expires(timer, mode);
         return 0;
 }
 
@@ -862,9 +839,7 @@ retry_delete:
          * This keeps any tasks waiting on the spin lock from thinking
          * they got something (see the lock code above).
          */
-        if (timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
-                put_task_struct(timer->it_process);
-        timer->it_process = NULL;
+        timer->it_signal = NULL;
 
         unlock_timer(timer, flags);
         release_posix_timer(timer, IT_ID_SET);
@@ -890,9 +865,7 @@ retry_delete:
          * This keeps any tasks waiting on the spin lock from thinking
          * they got something (see the lock code above).
          */
-        if (timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
-                put_task_struct(timer->it_process);
-        timer->it_process = NULL;
+        timer->it_signal = NULL;
 
         unlock_timer(timer, flags);
         release_posix_timer(timer, IT_ID_SET);