2 files changed, 107 insertions, 67 deletions

diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index 7a003504c265..1bdd2bf4f37d 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -730,13 +730,23 @@ static int send_prio_char(struct tty_struct *tty, char ch)
         return 0;
 }
 
-int n_tty_ioctl(struct tty_struct * tty, struct file * file,
-                       unsigned int cmd, unsigned long arg)
+/**
+ *      tty_mode_ioctl          -       mode related ioctls
+ *      @tty: tty for the ioctl
+ *      @file: file pointer for the tty
+ *      @cmd: command
+ *      @arg: ioctl argument
+ *
+ *      Perform non line discipline specific mode control ioctls. This
+ *      is designed to be called by line disciplines to ensure they provide
+ *      consistent mode setting.
+ */
+
+int tty_mode_ioctl(struct tty_struct * tty, struct file *file,
+                        unsigned int cmd, unsigned long arg)
 {
         struct tty_struct * real_tty;
         void __user *p = (void __user *)arg;
-        int retval;
-        struct tty_ldisc *ld;
 
         if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
             tty->driver->subtype == PTY_TYPE_MASTER)
@@ -799,6 +809,93 @@ int n_tty_ioctl(struct tty_struct * tty, struct file * file,
                         return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
                 case TCSETA:
                         return set_termios(real_tty, p, TERMIOS_TERMIO);
+#ifndef TCGETS2
+                case TIOCGLCKTRMIOS:
+                        if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
+                                return -EFAULT;
+                        return 0;
+
+                case TIOCSLCKTRMIOS:
+                        if (!capable(CAP_SYS_ADMIN))
+                                return -EPERM;
+                        if (user_termios_to_kernel_termios(real_tty->termios_locked, (struct termios __user *) arg))
+                                return -EFAULT;
+                        return 0;
+#else
+                case TIOCGLCKTRMIOS:
+                        if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios_locked))
+                                return -EFAULT;
+                        return 0;
+
+                case TIOCSLCKTRMIOS:
+                        if (!capable(CAP_SYS_ADMIN))
+                                return -EPERM;
+                        if (user_termios_to_kernel_termios_1(real_tty->termios_locked, (struct termios __user *) arg))
+                                return -EFAULT;
+                        return 0;
+#endif
+                case TIOCGSOFTCAR:
+                        return put_user(C_CLOCAL(tty) ? 1 : 0, (int __user *)arg);
+                case TIOCSSOFTCAR:
+                        if (get_user(arg, (unsigned int __user *) arg))
+                                return -EFAULT;
+                        mutex_lock(&tty->termios_mutex);
+                        tty->termios->c_cflag =
+                                ((tty->termios->c_cflag & ~CLOCAL) |
+                                 (arg ? CLOCAL : 0));
+                        mutex_unlock(&tty->termios_mutex);
+                        return 0;
+                default:
+                        return -ENOIOCTLCMD;
+        }
+}
+
+EXPORT_SYMBOL_GPL(tty_mode_ioctl);
+
+int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
+{
+        struct tty_ldisc *ld;
+        int retval = tty_check_change(tty);
+        if (retval)
+                return retval;
+
+        ld = tty_ldisc_ref(tty);
+        switch (arg) {
+        case TCIFLUSH:
+                if (ld && ld->flush_buffer)
+                        ld->flush_buffer(tty);
+                break;
+        case TCIOFLUSH:
+                if (ld && ld->flush_buffer)
+                        ld->flush_buffer(tty);
+                /* fall through */
+        case TCOFLUSH:
+                if (tty->driver->flush_buffer)
+                        tty->driver->flush_buffer(tty);
+                break;
+        default:
+                tty_ldisc_deref(ld);
+                return -EINVAL;
+        }
+        tty_ldisc_deref(ld);
+        return 0;
+}
+
+EXPORT_SYMBOL_GPL(tty_perform_flush);
+
+int n_tty_ioctl(struct tty_struct * tty, struct file * file,
+                       unsigned int cmd, unsigned long arg)
+{
+        struct tty_struct * real_tty;
+        int retval;
+
+        if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
+            tty->driver->subtype == PTY_TYPE_MASTER)
+                real_tty = tty->link;
+        else
+                real_tty = tty;
+
+        switch (cmd) {
                 case TCXONC:
                         retval = tty_check_change(tty);
                         if (retval)
@@ -829,30 +926,7 @@ int n_tty_ioctl(struct tty_struct * tty, struct file * file,
                         }
                         return 0;
                 case TCFLSH:
-                        retval = tty_check_change(tty);
-                        if (retval)
-                                return retval;
-                                
-                        ld = tty_ldisc_ref(tty);
-                        switch (arg) {
-                        case TCIFLUSH:
-                                if (ld && ld->flush_buffer)
-                                        ld->flush_buffer(tty);
-                                break;
-                        case TCIOFLUSH:
-                                if (ld && ld->flush_buffer)
-                                        ld->flush_buffer(tty);
-                                /* fall through */
-                        case TCOFLUSH:
-                                if (tty->driver->flush_buffer)
-                                        tty->driver->flush_buffer(tty);
-                                break;
-                        default:
-                                tty_ldisc_deref(ld);
-                                return -EINVAL;
-                        }
-                        tty_ldisc_deref(ld);
-                        return 0;
+                        return tty_perform_flush(tty, arg);
                 case TIOCOUTQ:
                         return put_user(tty->driver->chars_in_buffer ?
                                         tty->driver->chars_in_buffer(tty) : 0,
@@ -862,32 +936,6 @@ int n_tty_ioctl(struct tty_struct * tty, struct file * file,
                         if (L_ICANON(tty))
                                 retval = inq_canon(tty);
                         return put_user(retval, (unsigned int __user *) arg);
-#ifndef TCGETS2
-                case TIOCGLCKTRMIOS:
-                        if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
-                                return -EFAULT;
-                        return 0;
-
-                case TIOCSLCKTRMIOS:
-                        if (!capable(CAP_SYS_ADMIN))
-                                return -EPERM;
-                        if (user_termios_to_kernel_termios(real_tty->termios_locked, (struct termios __user *) arg))
-                                return -EFAULT;
-                        return 0;
-#else
-                case TIOCGLCKTRMIOS:
-                        if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios_locked))
-                                return -EFAULT;
-                        return 0;
-
-                case TIOCSLCKTRMIOS:
-                        if (!capable(CAP_SYS_ADMIN))
-                                return -EPERM;
-                        if (user_termios_to_kernel_termios_1(real_tty->termios_locked, (struct termios __user *) arg))
-                                return -EFAULT;
-                        return 0;
-#endif
-
                 case TIOCPKT:
                 {
                         int pktmode;
@@ -906,19 +954,9 @@ int n_tty_ioctl(struct tty_struct * tty, struct file * file,
                                 tty->packet = 0;
                         return 0;
                 }
-                case TIOCGSOFTCAR:
-                        return put_user(C_CLOCAL(tty) ? 1 : 0, (int __user *)arg);
-                case TIOCSSOFTCAR:
-                        if (get_user(arg, (unsigned int __user *) arg))
-                                return -EFAULT;
-                        mutex_lock(&tty->termios_mutex);
-                        tty->termios->c_cflag =
-                                ((tty->termios->c_cflag & ~CLOCAL) |
-                                 (arg ? CLOCAL : 0));
-                        mutex_unlock(&tty->termios_mutex);
-                        return 0;
                 default:
-                        return -ENOIOCTLCMD;
+                        /* Try the mode commands */
+                        return tty_mode_ioctl(tty, file, cmd, arg);
                 }
 }
 
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 56164d7ba0ad..c555f5442bd7 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -332,7 +332,9 @@ extern void tty_ldisc_flush(struct tty_struct *tty);
 
 extern int tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
                      unsigned long arg);
-
+extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
+                        unsigned int cmd, unsigned long arg);
+extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 extern dev_t tty_devnum(struct tty_struct *tty);
 extern void proc_clear_tty(struct task_struct *p);
 extern struct tty_struct *get_current_tty(void);