hrtimer: hook compat_sys_nanosleep up to high res timer code

Now we have high res timers on ppc64 I thought Id test them. It turns
out compat_sys_nanosleep hasnt been converted to the hrtimer code and so
is limited to HZ resolution.

The follow patch converts compat_sys_nanosleep to use high res timers.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/compat.c b/kernel/compat.c
index 3bae374..252a446 100644 (file)
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -40,62 +40,27 @@ int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user
                        __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
 
-static long compat_nanosleep_restart(struct restart_block *restart)
-{
-       unsigned long expire = restart->arg0, now = jiffies;
-       struct compat_timespec __user *rmtp;
-
-       /* Did it expire while we handled signals? */
-       if (!time_after(expire, now))
-               return 0;
-
-       expire = schedule_timeout_interruptible(expire - now);
-       if (expire == 0)
-               return 0;
-
-       rmtp = (struct compat_timespec __user *)restart->arg1;
-       if (rmtp) {
-               struct compat_timespec ct;
-               struct timespec t;
-
-               jiffies_to_timespec(expire, &t);
-               ct.tv_sec = t.tv_sec;
-               ct.tv_nsec = t.tv_nsec;
-               if (copy_to_user(rmtp, &ct, sizeof(ct)))
-                       return -EFAULT;
-       }
-       /* The 'restart' block is already filled in */
-       return -ERESTART_RESTARTBLOCK;
-}
-
 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
-               struct compat_timespec __user *rmtp)
+                                    struct compat_timespec __user *rmtp)
 {
-       struct timespec t;
-       struct restart_block *restart;
-       unsigned long expire;
+       struct timespec tu, rmt;
+       long ret;
 
-       if (get_compat_timespec(&t, rqtp))
+       if (get_compat_timespec(&tu, rqtp))
                return -EFAULT;
 
-       if ((t.tv_nsec >= 1000000000L) || (t.tv_nsec < 0) || (t.tv_sec < 0))
+       if (!timespec_valid(&tu))
                return -EINVAL;
 
-       expire = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
-       expire = schedule_timeout_interruptible(expire);
-       if (expire == 0)
-               return 0;
+       ret = hrtimer_nanosleep(&tu, rmtp ? &rmt : NULL, HRTIMER_MODE_REL,
+                               CLOCK_MONOTONIC);
 
-       if (rmtp) {
-               jiffies_to_timespec(expire, &t);
-               if (put_compat_timespec(&t, rmtp))
+       if (ret && rmtp) {
+               if (put_compat_timespec(&rmt, rmtp))
                        return -EFAULT;
        }
-       restart = &current_thread_info()->restart_block;
-       restart->fn = compat_nanosleep_restart;
-       restart->arg0 = jiffies + expire;
-       restart->arg1 = (unsigned long) rmtp;
-       return -ERESTART_RESTARTBLOCK;
+
+       return ret;
 }
 
 static inline long get_compat_itimerval(struct itimerval *o,