diff options
Diffstat (limited to 'drivers/tty/tty_ldisc.c')
-rw-r--r-- | drivers/tty/tty_ldisc.c | 84 |
1 files changed, 47 insertions, 37 deletions
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 6f99c9959f0c..0f2a2c5e704c 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -413,7 +413,7 @@ EXPORT_SYMBOL_GPL(tty_ldisc_flush); static void tty_set_termios_ldisc(struct tty_struct *tty, int num) { mutex_lock(&tty->termios_mutex); - tty->termios->c_line = num; + tty->termios.c_line = num; mutex_unlock(&tty->termios_mutex); } @@ -523,9 +523,9 @@ static int tty_ldisc_halt(struct tty_struct *tty) */ static void tty_ldisc_flush_works(struct tty_struct *tty) { - flush_work_sync(&tty->hangup_work); - flush_work_sync(&tty->SAK_work); - flush_work_sync(&tty->buf.work); + flush_work(&tty->hangup_work); + flush_work(&tty->SAK_work); + flush_work(&tty->buf.work); } /** @@ -568,7 +568,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) if (IS_ERR(new_ldisc)) return PTR_ERR(new_ldisc); - tty_lock(); + tty_lock(tty); /* * We need to look at the tty locking here for pty/tty pairs * when both sides try to change in parallel. @@ -582,12 +582,12 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) */ if (tty->ldisc->ops->num == ldisc) { - tty_unlock(); + tty_unlock(tty); tty_ldisc_put(new_ldisc); return 0; } - tty_unlock(); + tty_unlock(tty); /* * Problem: What do we do if this blocks ? * We could deadlock here @@ -595,7 +595,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) tty_wait_until_sent(tty, 0); - tty_lock(); + tty_lock(tty); mutex_lock(&tty->ldisc_mutex); /* @@ -605,10 +605,10 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) while (test_bit(TTY_LDISC_CHANGING, &tty->flags)) { mutex_unlock(&tty->ldisc_mutex); - tty_unlock(); + tty_unlock(tty); wait_event(tty_ldisc_wait, test_bit(TTY_LDISC_CHANGING, &tty->flags) == 0); - tty_lock(); + tty_lock(tty); mutex_lock(&tty->ldisc_mutex); } @@ -623,7 +623,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) o_ldisc = tty->ldisc; - tty_unlock(); + tty_unlock(tty); /* * Make sure we don't change while someone holds a * reference to the line discipline. The TTY_LDISC bit @@ -650,7 +650,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) retval = tty_ldisc_wait_idle(tty, 5 * HZ); - tty_lock(); + tty_lock(tty); mutex_lock(&tty->ldisc_mutex); /* handle wait idle failure locked */ @@ -665,7 +665,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) clear_bit(TTY_LDISC_CHANGING, &tty->flags); mutex_unlock(&tty->ldisc_mutex); tty_ldisc_put(new_ldisc); - tty_unlock(); + tty_unlock(tty); return -EIO; } @@ -708,7 +708,7 @@ enable: if (o_work) schedule_work(&o_tty->buf.work); mutex_unlock(&tty->ldisc_mutex); - tty_unlock(); + tty_unlock(tty); return retval; } @@ -722,9 +722,9 @@ enable: static void tty_reset_termios(struct tty_struct *tty) { mutex_lock(&tty->termios_mutex); - *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); + 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); } @@ -816,11 +816,11 @@ void tty_ldisc_hangup(struct tty_struct *tty) * need to wait for another function taking the BTM */ clear_bit(TTY_LDISC, &tty->flags); - tty_unlock(); + tty_unlock(tty); cancel_work_sync(&tty->buf.work); mutex_unlock(&tty->ldisc_mutex); retry: - tty_lock(); + tty_lock(tty); mutex_lock(&tty->ldisc_mutex); /* At this point we have a closed ldisc and we want to @@ -831,7 +831,7 @@ retry: if (atomic_read(&tty->ldisc->users) != 1) { char cur_n[TASK_COMM_LEN], tty_n[64]; long timeout = 3 * HZ; - tty_unlock(); + tty_unlock(tty); while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) { timeout = MAX_SCHEDULE_TIMEOUT; @@ -846,7 +846,7 @@ retry: if (reset == 0) { - if (!tty_ldisc_reinit(tty, tty->termios->c_line)) + if (!tty_ldisc_reinit(tty, tty->termios.c_line)) err = tty_ldisc_open(tty, tty->ldisc); else err = 1; @@ -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 @@ -912,28 +929,21 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty) * race with the set_ldisc code path. */ - tty_unlock(); + tty_lock_pair(tty, o_tty); tty_ldisc_halt(tty); tty_ldisc_flush_works(tty); - tty_lock(); - - 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); + if (o_tty) { + tty_ldisc_halt(o_tty); + tty_ldisc_flush_works(o_tty); + } /* 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); + tty_unlock_pair(tty, o_tty); /* And the memory resources remaining (buffers, termios) will be disposed of when the kref hits zero */ } |