signal/timer/event: timerfd compat code

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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 32 insertions, 4 deletions

diff --git a/fs/compat.c b/fs/compat.c
index 2487b83b18df..7b21b0a82596 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -2225,3 +2225,26 @@ asmlinkage long compat_sys_signalfd(int ufd,
 
 #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 --git a/include/linux/compat.h b/include/linux/compat.h
index 70a157a130bb..636502c02734 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -225,6 +225,11 @@ static inline int compat_timespec_compare(struct compat_timespec *lhs,
         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 --git a/kernel/compat.c b/kernel/compat.c
index cebb4c28c039..3bae3742c2aa 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -475,8 +475,8 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
         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 itimerspec *dst,
         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))