Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

[firefly-linux-kernel-4.4.55.git] / drivers / tty / tty_ldisc.c

diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 75fa99978348db2465cb35bace4e38429f4feaa8..6458e11e8e9d656daef35b0a5aaddc21dcfd1804 100644 (file)
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -415,14 +415,14 @@ EXPORT_SYMBOL_GPL(tty_ldisc_flush);
  *     they are not on hot paths so a little discipline won't do
  *     any harm.
  *
- *     Locking: takes termios_mutex
+ *     Locking: takes termios_rwsem
  */
 
 static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
 {
-       mutex_lock(&tty->termios_mutex);
+       down_write(&tty->termios_rwsem);
        tty->termios.c_line = num;
-       mutex_unlock(&tty->termios_mutex);
+       up_write(&tty->termios_rwsem);
 }
 
 /**
@@ -540,9 +540,6 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
                return 0;
        }
 
-       /* FIXME: why 'shutoff' input if the ldisc is locked? */
-       tty->receive_room = 0;
-
        old_ldisc = tty->ldisc;
        tty_lock(tty);
 
@@ -605,11 +602,11 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 
 static void tty_reset_termios(struct tty_struct *tty)
 {
-       mutex_lock(&tty->termios_mutex);
+       down_write(&tty->termios_rwsem);
        tty->termios = tty->driver->init_termios;
        tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios);
        tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios);
-       mutex_unlock(&tty->termios_mutex);
+       up_write(&tty->termios_rwsem);
 }