From: Davide Libenzi <davidel@xmailserver.org>

This patch implements the necessary compat code for the timerfd system call.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/compat.c            |   23 +++++++++++++++++++++++
 include/linux/compat.h |    5 +++++
 kernel/compat.c        |    8 ++++----
 3 files changed, 32 insertions(+), 4 deletions(-)

diff -puN fs/compat.c~signal-timer-event-fds-v9-timerfd-compat-code fs/compat.c
--- a/fs/compat.c~signal-timer-event-fds-v9-timerfd-compat-code
+++ a/fs/compat.c
@@ -2225,3 +2225,26 @@ asmlinkage long compat_sys_signalfd(int 
 
 #endif /* CONFIG_SIGNALFD */
 
+#ifdef CONFIG_TIMERFD
+
+asmlinkage long compat_sys_timerfd(int ufd, int clockid, int flags,
+				   const struct compat_itimerspec __user *utmr)
+{
+	long res;
+	struct itimerspec t;
+	struct itimerspec __user *ut;
+
+	res = -EFAULT;
+	if (get_compat_itimerspec(&t, utmr))
+		goto err_exit;
+	ut = compat_alloc_user_space(sizeof(*ut));
+	if (copy_to_user(ut, &t, sizeof(t)) )
+		goto err_exit;
+
+	res = sys_timerfd(ufd, clockid, flags, ut);
+err_exit:
+	return res;
+}
+
+#endif /* CONFIG_TIMERFD */
+
diff -puN include/linux/compat.h~signal-timer-event-fds-v9-timerfd-compat-code include/linux/compat.h
--- a/include/linux/compat.h~signal-timer-event-fds-v9-timerfd-compat-code
+++ a/include/linux/compat.h
@@ -225,6 +225,11 @@ static inline int compat_timespec_compar
 	return lhs->tv_nsec - rhs->tv_nsec;
 }
 
+extern int get_compat_itimerspec(struct itimerspec *dst,
+				 const struct compat_itimerspec __user *src);
+extern int put_compat_itimerspec(struct compat_itimerspec __user *dst,
+				 const struct itimerspec *src);
+
 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp);
 
 extern int compat_printk(const char *fmt, ...);
diff -puN kernel/compat.c~signal-timer-event-fds-v9-timerfd-compat-code kernel/compat.c
--- a/kernel/compat.c~signal-timer-event-fds-v9-timerfd-compat-code
+++ a/kernel/compat.c
@@ -475,8 +475,8 @@ asmlinkage long compat_sys_sched_getaffi
 	return min_length;
 }
 
-static int get_compat_itimerspec(struct itimerspec *dst, 
-				 struct compat_itimerspec __user *src)
+int get_compat_itimerspec(struct itimerspec *dst,
+			  const struct compat_itimerspec __user *src)
 { 
 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
 	    get_compat_timespec(&dst->it_value, &src->it_value))
@@ -484,8 +484,8 @@ static int get_compat_itimerspec(struct 
 	return 0;
 } 
 
-static int put_compat_itimerspec(struct compat_itimerspec __user *dst, 
-				 struct itimerspec *src)
+int put_compat_itimerspec(struct compat_itimerspec __user *dst,
+			  const struct itimerspec *src)
 { 
 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
 	    put_compat_timespec(&src->it_value, &dst->it_value))
_