tty: remove resize window special case

[linux-2.6-omap-h63xx.git] / drivers / char / tty_io.c

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 0e6866fe0f96d5fb19b0098a85d4a5ba52351d33..a27160ba21d7d8cb8eb9636da015075b1bc5b587 100644 (file)
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -2496,45 +2496,25 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg)
 }
 
 /**
- *     tiocswinsz              -       implement window size set ioctl
- *     @tty; tty
- *     @arg: user buffer for result
+ *     tty_do_resize           -       resize event
+ *     @tty: tty being resized
+ *     @real_tty: real tty (if using a pty/tty pair)
+ *     @rows: rows (character)
+ *     @cols: cols (character)
  *
- *     Copies the user idea of the window size to the kernel. Traditionally
- *     this is just advisory information but for the Linux console it
- *     actually has driver level meaning and triggers a VC resize.
- *
- *     Locking:
- *             Called function use the console_sem is used to ensure we do
- *     not try and resize the console twice at once.
- *             The tty->termios_mutex is used to ensure we don't double
- *     resize and get confused. Lock order - tty->termios_mutex before
- *     console sem
+ *     Update the termios variables and send the neccessary signals to
+ *     peform a terminal resize correctly
  */
 
-static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
-       struct winsize __user *arg)
+int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
+                                       struct winsize *ws)
 {
-       struct winsize tmp_ws;
        struct pid *pgrp, *rpgrp;
        unsigned long flags;
 
-       if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))
-               return -EFAULT;
-
        mutex_lock(&tty->termios_mutex);
-       if (!memcmp(&tmp_ws, &tty->winsize, sizeof(*arg)))
+       if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
                goto done;
-
-#ifdef CONFIG_VT
-       if (tty->driver->type == TTY_DRIVER_TYPE_CONSOLE) {
-               if (vc_lock_resize(tty->driver_data, tmp_ws.ws_col,
-                                       tmp_ws.ws_row)) {
-                       mutex_unlock(&tty->termios_mutex);
-                       return -ENXIO;
-               }
-       }
-#endif
        /* Get the PID values and reference them so we can
           avoid holding the tty ctrl lock while sending signals */
        spin_lock_irqsave(&tty->ctrl_lock, flags);
@@ -2550,13 +2530,41 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
        put_pid(pgrp);
        put_pid(rpgrp);
 
-       tty->winsize = tmp_ws;
-       real_tty->winsize = tmp_ws;
+       tty->winsize = *ws;
+       real_tty->winsize = *ws;
 done:
        mutex_unlock(&tty->termios_mutex);
        return 0;
 }
 
+/**
+ *     tiocswinsz              -       implement window size set ioctl
+ *     @tty; tty
+ *     @arg: user buffer for result
+ *
+ *     Copies the user idea of the window size to the kernel. Traditionally
+ *     this is just advisory information but for the Linux console it
+ *     actually has driver level meaning and triggers a VC resize.
+ *
+ *     Locking:
+ *             Driver dependant. The default do_resize method takes the
+ *     tty termios mutex and ctrl_lock. The console takes its own lock
+ *     then calls into the default method.
+ */
+
+static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
+       struct winsize __user *arg)
+{
+       struct winsize tmp_ws;
+       if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))
+               return -EFAULT;
+
+       if (tty->ops->resize)
+               return tty->ops->resize(tty, real_tty, &tmp_ws);
+       else
+               return tty_do_resize(tty, real_tty, &tmp_ws);
+}
+
 /**
  *     tioccons        -       allow admin to move logical console
  *     @file: the file to become console