[PATCH 07/16] {clock_,}nanosleep(2): merge timespec copyout logics into a new helper

[Al Viro <viro@ZenIV.linux.org.uk>]

From: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 include/linux/hrtimer.h        |  2 ++
 kernel/time/alarmtimer.c       | 10 +---------
 kernel/time/hrtimer.c          | 24 +++++++++++++++---------
 kernel/time/posix-cpu-timers.c | 13 ++-----------
 4 files changed, 20 insertions(+), 29 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index b80c34f6fd4b..38b968f3df4e 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -452,6 +452,8 @@ static inline u64 hrtimer_forward_now(struct hrtimer *timer,
 }
 
 /* Precise sleep: */
+
+extern int nanosleep_copyout(struct restart_block *, struct timespec *);
 extern long hrtimer_nanosleep(struct timespec64 *rqtp,
 			      const enum hrtimer_mode mode,
 			      const clockid_t clockid);
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 868083ae7434..80154e795535 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -721,15 +721,7 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
 			return 0;
 		rmt = ktime_to_timespec(rem);
 
-#ifdef CONFIG_COMPAT
-		if (restart->nanosleep.kind == 2) {
-			if (compat_put_timespec(&rmt,
-						restart->nanosleep.compat_rmtp))
-				return -EFAULT;
-		} else
-#endif
-		if (copy_to_user(restart->nanosleep.rmtp, &rmt, sizeof(rmt)))
-			return -EFAULT;
+		return nanosleep_copyout(restart, &rmt);
 	}
 	return -ERESTART_RESTARTBLOCK;
 }
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 5534606e3985..6c19995e977e 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1440,6 +1440,20 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
 }
 EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
 
+int nanosleep_copyout(struct restart_block *restart, struct timespec *ts)
+{
+	BUG_ON(!restart->nanosleep.kind);
+#ifdef CONFIG_COMPAT
+	if (restart->nanosleep.kind == 2) {
+		if (compat_put_timespec(ts, restart->nanosleep.compat_rmtp))
+			return -EFAULT;
+	} else
+#endif
+	if (copy_to_user(restart->nanosleep.rmtp, ts, sizeof(struct timespec)))
+		return -EFAULT;
+	return -ERESTART_RESTARTBLOCK;
+}
+
 static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode)
 {
 	struct restart_block *restart;
@@ -1470,15 +1484,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 			return 0;
 		rmt = ktime_to_timespec(rem);
 
-#ifdef CONFIG_COMPAT
-		if (restart->nanosleep.kind == 2) {
-			if (compat_put_timespec(&rmt,
-						restart->nanosleep.compat_rmtp))
-				return -EFAULT;
-		} else
-#endif
-		if (copy_to_user(restart->nanosleep.rmtp, &rmt, sizeof(rmt)))
-			return -EFAULT;
+		return nanosleep_copyout(restart, &rmt);
 	}
 	return -ERESTART_RESTARTBLOCK;
 }
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index b88bc3fc56c5..ba0d7e34616b 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1312,21 +1312,12 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
 		 * Report back to the user the time still remaining.
 		 */
 		restart = &current->restart_block;
+		restart->nanosleep.expires = timespec64_to_ns(rqtp);
 		if (restart->nanosleep.kind) {
 			struct timespec ts;
 			ts = timespec64_to_timespec(it.it_value);
-#ifdef CONFIG_COMPAT
-			if (restart->nanosleep.kind == 2) {
-				if (compat_put_timespec(&ts,
-						restart->nanosleep.compat_rmtp))
-					return -EFAULT;
-			} else
-#endif
-			if (copy_to_user(restart->nanosleep.rmtp, &ts,
-					sizeof(ts)))
-				return -EFAULT;
+			error = nanosleep_copyout(restart, &ts);
 		}
-		restart->nanosleep.expires = timespec64_to_ns(rqtp);
 	}
 
 	return error;
-- 
2.11.0