hrtimer: Rework hrtimer_nanosleep to make sys_compat_nanosleep easier

Pull the copy_to_user out of hrtimer_nanosleep and into the callers
(common_nsleep, sys_nanosleep) in preparation for converting
compat_sys_nanosleep to use hrtimers.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 14 insertions, 3 deletions

diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index d71ed09fe1dd..d11f579d189a 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -981,9 +981,20 @@ sys_clock_getres(const clockid_t which_clock, struct timespec __user *tp)
 static int common_nsleep(const clockid_t which_clock, int flags,
                          struct timespec *tsave, struct timespec __user *rmtp)
 {
-        return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
-                                 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
-                                 which_clock);
+        struct timespec rmt;
+        int ret;
+
+        ret = hrtimer_nanosleep(tsave, rmtp ? &rmt : NULL,
+                                flags & TIMER_ABSTIME ?
+                                HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+                                which_clock);
+
+        if (ret && rmtp) {
+                if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
+                        return -EFAULT;
+        }
+
+        return ret;
 }
 
 asmlinkage long