tty: pty - Move TIOCPKT handling into pty.c

Since this ioctl is for pty devices only move it to pty.c.

v2:
 - drop PTY_TYPE_MASTER test since it's master peer
   ioctl anyway (by jslaby@)

Suggested-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 4219f04..df3c642 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -171,6 +171,28 @@
 	return 0;
 }
 
+/* Set the packet mode on a pty */
+static int pty_set_pktmode(struct tty_struct *tty, int __user *arg)
+{
+	unsigned long flags;
+	int pktmode;
+
+	if (get_user(pktmode, arg))
+		return -EFAULT;
+
+	spin_lock_irqsave(&tty->ctrl_lock, flags);
+	if (pktmode) {
+		if (!tty->packet) {
+			tty->packet = 1;
+			tty->link->ctrl_status = 0;
+		}
+	} else
+		tty->packet = 0;
+	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+
+	return 0;
+}
+
 /* Send a signal to the slave */
 static int pty_signal(struct tty_struct *tty, int sig)
 {
@@ -398,6 +420,8 @@
 	switch (cmd) {
 	case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
 		return pty_set_lock(tty, (int __user *) arg);
+	case TIOCPKT: /* Set PT packet mode */
+		return pty_set_pktmode(tty, (int __user *)arg);
 	case TIOCSIG:    /* Send signal to other side of pty */
 		return pty_signal(tty, (int) arg);
 	}
@@ -512,6 +536,8 @@
 	switch (cmd) {
 	case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
 		return pty_set_lock(tty, (int __user *)arg);
+	case TIOCPKT: /* Set PT packet mode */
+		return pty_set_pktmode(tty, (int __user *)arg);
 	case TIOCGPTN: /* Get PT Number */
 		return put_user(tty->index, (unsigned int __user *)arg);
 	case TIOCSIG:    /* Send signal to other side of pty */