switch getrusage() to COMPAT_SYSCALL_DEFINE

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

kernel/sys.c

@@ -1784,6 +1784,20 @@ SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru)
 	return getrusage(current, who, ru);
 }
 
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru)
+{
+	struct rusage r;
+
+	if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+	    who != RUSAGE_THREAD)
+		return -EINVAL;
+
+	k_getrusage(current, who, &r);
+	return put_compat_rusage(&r, ru);
+}
+#endif
+
 SYSCALL_DEFINE1(umask, int, mask)
 {
 	mask = xchg(&current->fs->umask, mask & S_IRWXUGO);