diff options
Diffstat (limited to 'drivers/tty/tty_ldisc.c')
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 47 |
1 files changed, 12 insertions, 35 deletions
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 9c727da59fa..cbb945b03cd 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -508,7 +508,6 @@ static void tty_ldisc_flush_works(struct tty_struct *tty) { flush_work(&tty->SAK_work); flush_work(&tty->hangup_work); - flush_work(&tty->port->buf.work); } /** @@ -531,20 +530,12 @@ static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout) * tty_ldisc_halt - shut down the line discipline * @tty: tty device * @o_tty: paired pty device (can be NULL) - * @pending: returns true if work was scheduled when cancelled - * (can be set to NULL) - * @o_pending: returns true if work was scheduled when cancelled - * (can be set to NULL) * @timeout: # of jiffies to wait for ldisc refs to be released * * Shut down the line discipline and work queue for this tty device and * its paired pty (if exists). Clearing the TTY_LDISC flag ensures - * no further references can be obtained while the work queue halt - * ensures that no more data is fed to the ldisc. - * - * Furthermore, guarantee that existing ldisc references have been - * released, which in turn, guarantees that no future buffer work - * can be rescheduled. + * no further references can be obtained, while waiting for existing + * references to be released ensures no more data is fed to the ldisc. * * You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex) * in order to make sure any currently executing ldisc work is also @@ -552,9 +543,9 @@ static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout) */ static int tty_ldisc_halt(struct tty_struct *tty, struct tty_struct *o_tty, - int *pending, int *o_pending, long timeout) + long timeout) { - int scheduled, o_scheduled, retval; + int retval; clear_bit(TTY_LDISC, &tty->flags); if (o_tty) @@ -566,17 +557,10 @@ static int tty_ldisc_halt(struct tty_struct *tty, struct tty_struct *o_tty, if (retval) return retval; - scheduled = cancel_work_sync(&tty->port->buf.work); set_bit(TTY_LDISC_HALTED, &tty->flags); - if (o_tty) { - o_scheduled = cancel_work_sync(&o_tty->port->buf.work); + if (o_tty) set_bit(TTY_LDISC_HALTED, &o_tty->flags); - } - if (pending) - *pending = scheduled; - if (o_tty && o_pending) - *o_pending = o_scheduled; return 0; } @@ -586,17 +570,12 @@ static int tty_ldisc_halt(struct tty_struct *tty, struct tty_struct *o_tty, * * Shut down the line discipline and work queue for the tty device * being hungup. Clear the TTY_LDISC flag to ensure no further - * references can be obtained, wait for remaining references to be - * released, and cancel pending buffer work to ensure no more - * data is fed to this ldisc. + * references can be obtained and wait for remaining references to be + * released to ensure no more data is fed to this ldisc. * Caller must hold legacy and ->ldisc_mutex. * * NB: tty_set_ldisc() is prevented from changing the ldisc concurrently * with this function by checking the TTY_HUPPING flag. - * - * NB: if tty->ldisc is NULL then buffer work does not need to be - * cancelled because it must already have done as a precondition - * of closing the ldisc and setting tty->ldisc to NULL */ static bool tty_ldisc_hangup_halt(struct tty_struct *tty) { @@ -616,7 +595,6 @@ static bool tty_ldisc_hangup_halt(struct tty_struct *tty) tty_name(tty, tty_n)); } - cancel_work_sync(&tty->port->buf.work); set_bit(TTY_LDISC_HALTED, &tty->flags); /* must reacquire both locks and preserve lock order */ @@ -644,7 +622,6 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) { int retval; struct tty_ldisc *o_ldisc, *new_ldisc; - int work, o_work = 0; struct tty_struct *o_tty; new_ldisc = tty_ldisc_get(ldisc); @@ -718,7 +695,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) * parallel to the change and re-referencing the tty. */ - retval = tty_ldisc_halt(tty, o_tty, &work, &o_work, 5 * HZ); + retval = tty_ldisc_halt(tty, o_tty, 5 * HZ); /* * Wait for ->hangup_work and ->buf.work handlers to terminate. @@ -782,10 +759,10 @@ enable: /* Restart the work queue in case no characters kick it off. Safe if already running */ - if (work) - schedule_work(&tty->port->buf.work); - if (o_work) + schedule_work(&tty->port->buf.work); + if (o_tty) schedule_work(&o_tty->port->buf.work); + mutex_unlock(&tty->ldisc_mutex); tty_unlock(tty); return retval; @@ -979,7 +956,7 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty) * race with the set_ldisc code path. */ - tty_ldisc_halt(tty, o_tty, NULL, NULL, MAX_SCHEDULE_TIMEOUT); + tty_ldisc_halt(tty, o_tty, MAX_SCHEDULE_TIMEOUT); tty_ldisc_flush_works(tty); if (o_tty) tty_ldisc_flush_works(o_tty); |