diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 41 |
1 files changed, 25 insertions, 16 deletions
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 173a9000a6cb..ba8be396a621 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -894,6 +894,23 @@ int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty) tty_ldisc_enable(tty); return 0; } + +static void tty_ldisc_kill(struct tty_struct *tty) +{ + mutex_lock(&tty->ldisc_mutex); + /* + * Now kill off the ldisc + */ + tty_ldisc_close(tty, tty->ldisc); + tty_ldisc_put(tty->ldisc); + /* Force an oops if we mess this up */ + tty->ldisc = NULL; + + /* Ensure the next open requests the N_TTY ldisc */ + tty_set_termios_ldisc(tty, N_TTY); + mutex_unlock(&tty->ldisc_mutex); +} + /** * tty_ldisc_release - release line discipline * @tty: tty being shut down @@ -912,27 +929,19 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty) * race with the set_ldisc code path. */ - tty_unlock(tty); + tty_unlock_pair(tty, o_tty); tty_ldisc_halt(tty); tty_ldisc_flush_works(tty); - tty_lock(tty); - - mutex_lock(&tty->ldisc_mutex); - /* - * Now kill off the ldisc - */ - tty_ldisc_close(tty, tty->ldisc); - tty_ldisc_put(tty->ldisc); - /* Force an oops if we mess this up */ - tty->ldisc = NULL; + if (o_tty) { + tty_ldisc_halt(o_tty); + tty_ldisc_flush_works(o_tty); + } + tty_lock_pair(tty, o_tty); - /* Ensure the next open requests the N_TTY ldisc */ - tty_set_termios_ldisc(tty, N_TTY); - mutex_unlock(&tty->ldisc_mutex); - /* This will need doing differently if we need to lock */ + tty_ldisc_kill(tty); if (o_tty) - tty_ldisc_release(o_tty, NULL); + tty_ldisc_kill(o_tty); /* And the memory resources remaining (buffers, termios) will be disposed of when the kref hits zero */ |