[PATCH] posix-timers: Fix clock_nanosleep() doesn't return the remaining time in compatibility mode

The clock_nanosleep() function does not return the time remaining when the
sleep is interrupted by a signal.

This patch creates a new call out, compat_clock_nanosleep_restart(), which
handles returning the remaining time after a sleep is interrupted.  This
patch revives clock_nanosleep_restart().  It is now accessed via the new
call out.  The compat_clock_nanosleep_restart() is used for compatibility
access.

Since this is implemented in compatibility mode the normal path is
virtually unaffected - no real performance impact.

Signed-off-by: Toyo Abe <toyoa@mvista.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 4fc379de6c2f..fca93025ab51 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -138,6 +138,7 @@ extern long hrtimer_nanosleep(struct timespec *rqtp,
                               struct timespec __user *rmtp,
                               const enum hrtimer_mode mode,
                               const clockid_t clockid);
+extern long hrtimer_nanosleep_restart(struct restart_block *restart_block);
 
 extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
                                  struct task_struct *tsk);
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index 95572c434bc9..a7dd38f30ade 100644
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -72,6 +72,7 @@ struct k_clock {
         int (*timer_create) (struct k_itimer *timer);
         int (*nsleep) (const clockid_t which_clock, int flags,
                        struct timespec *, struct timespec __user *);
+        long (*nsleep_restart) (struct restart_block *restart_block);
         int (*timer_set) (struct k_itimer * timr, int flags,
                           struct itimerspec * new_setting,
                           struct itimerspec * old_setting);
@@ -97,6 +98,7 @@ int posix_cpu_clock_set(const clockid_t which_clock, const struct timespec *ts);
 int posix_cpu_timer_create(struct k_itimer *timer);
 int posix_cpu_nsleep(const clockid_t which_clock, int flags,
                      struct timespec *rqtp, struct timespec __user *rmtp);
+long posix_cpu_nsleep_restart(struct restart_block *restart_block);
 int posix_cpu_timer_set(struct k_itimer *timer, int flags,
                         struct itimerspec *new, struct itimerspec *old);
 int posix_cpu_timer_del(struct k_itimer *timer);
@@ -111,4 +113,6 @@ void posix_cpu_timers_exit_group(struct task_struct *task);
 void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
                            cputime_t *newval, cputime_t *oldval);
 
+long clock_nanosleep_restart(struct restart_block *restart_block);
+
 #endif