1 files changed, 14 insertions, 35 deletions

diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 6fd60fece6b..62380ccf70f 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -402,7 +402,7 @@ void tty_termios_encode_baud_rate(struct ktermios *termios,
 
 #ifdef BOTHER
 	/* If the user asked for a precise weird speed give a precise weird
-	   answer. If they asked for a Bfoo speed they many have problems
+	   answer. If they asked for a Bfoo speed they may have problems
 	   digesting non-exact replies so fuzz a bit */
 
 	if ((termios->c_cflag & CBAUD) == BOTHER)
@@ -912,35 +912,6 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 #endif
 
 /**
- *	send_prio_char		-	send priority character
- *
- *	Send a high priority character to the tty even if stopped
- *
- *	Locking: none for xchar method, write ordering for write method.
- */
-
-static int send_prio_char(struct tty_struct *tty, char ch)
-{
-	int	was_stopped = tty->stopped;
-
-	if (tty->ops->send_xchar) {
-		tty->ops->send_xchar(tty, ch);
-		return 0;
-	}
-
-	if (tty_write_lock(tty, 0) < 0)
-		return -ERESTARTSYS;
-
-	if (was_stopped)
-		start_tty(tty);
-	tty->ops->write(tty, &ch, 1);
-	if (was_stopped)
-		stop_tty(tty);
-	tty_write_unlock(tty);
-	return 0;
-}
-
-/**
  *	tty_change_softcar	-	carrier change ioctl helper
  *	@tty: tty to update
  *	@arg: enable/disable CLOCAL
@@ -1177,29 +1148,37 @@ int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 			return retval;
 		switch (arg) {
 		case TCOOFF:
+			spin_lock_irq(&tty->flow_lock);
 			if (!tty->flow_stopped) {
 				tty->flow_stopped = 1;
-				stop_tty(tty);
+				__stop_tty(tty);
 			}
+			spin_unlock_irq(&tty->flow_lock);
 			break;
 		case TCOON:
+			spin_lock_irq(&tty->flow_lock);
 			if (tty->flow_stopped) {
 				tty->flow_stopped = 0;
-				start_tty(tty);
+				__start_tty(tty);
 			}
+			spin_unlock_irq(&tty->flow_lock);
 			break;
 		case TCIOFF:
+			down_read(&tty->termios_rwsem);
 			if (STOP_CHAR(tty) != __DISABLED_CHAR)
-				return send_prio_char(tty, STOP_CHAR(tty));
+				retval = tty_send_xchar(tty, STOP_CHAR(tty));
+			up_read(&tty->termios_rwsem);
 			break;
 		case TCION:
+			down_read(&tty->termios_rwsem);
 			if (START_CHAR(tty) != __DISABLED_CHAR)
-				return send_prio_char(tty, START_CHAR(tty));
+				retval = tty_send_xchar(tty, START_CHAR(tty));
+			up_read(&tty->termios_rwsem);
 			break;
 		default:
 			return -EINVAL;
 		}
-		return 0;
+		return retval;
 	case TCFLSH:
 		retval = tty_check_change(tty);
 		if (retval)