diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index c09db11b8831..679294b37653 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -194,6 +194,7 @@ struct gsm_control { struct gsm_mux { struct tty_struct *tty; /* The tty our ldisc is bound to */ spinlock_t lock; + struct mutex mutex; unsigned int num; struct kref ref; @@ -2054,9 +2055,11 @@ void gsm_cleanup_mux(struct gsm_mux *gsm) dlci->state == DLCI_CLOSED); } /* Free up any link layer users */ + mutex_lock(&gsm->mutex); for (i = 0; i < NUM_DLCI; i++) if (gsm->dlci[i]) gsm_dlci_release(gsm->dlci[i]); + mutex_unlock(&gsm->mutex); /* Now wipe the queues */ list_for_each_entry_safe(txq, ntxq, &gsm->tx_list, list) kfree(txq); @@ -2170,6 +2173,7 @@ struct gsm_mux *gsm_alloc_mux(void) return NULL; } spin_lock_init(&gsm->lock); + mutex_init(&gsm->mutex); kref_init(&gsm->ref); INIT_LIST_HEAD(&gsm->tx_list); @@ -2910,23 +2914,33 @@ static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty) This is ok from a locking perspective as we don't have to worry about this if DLCI0 is lost */ - if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN) + mutex_lock(&gsm->mutex); + if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN) { + mutex_unlock(&gsm->mutex); return -EL2NSYNC; + } dlci = gsm->dlci[line]; if (dlci == NULL) { alloc = true; dlci = gsm_dlci_alloc(gsm, line); } - if (dlci == NULL) + if (dlci == NULL) { + mutex_unlock(&gsm->mutex); return -ENOMEM; + } ret = tty_port_install(&dlci->port, driver, tty); if (ret) { if (alloc) dlci_put(dlci); + mutex_unlock(&gsm->mutex); return ret; } + dlci_get(dlci); + dlci_get(gsm->dlci[0]); + mux_get(gsm); tty->driver_data = dlci; + mutex_unlock(&gsm->mutex); return 0; } @@ -2937,9 +2951,6 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp) struct tty_port *port = &dlci->port; port->count++; - dlci_get(dlci); - dlci_get(dlci->gsm->dlci[0]); - mux_get(dlci->gsm); tty_port_tty_set(port, tty); dlci->modem_rx = 0; @@ -2966,7 +2977,7 @@ static void gsmtty_close(struct tty_struct *tty, struct file *filp) mutex_unlock(&dlci->mutex); gsm = dlci->gsm; if (tty_port_close_start(&dlci->port, tty, filp) == 0) - goto out; + return; gsm_dlci_begin_close(dlci); if (test_bit(ASYNCB_INITIALIZED, &dlci->port.flags)) { if (C_HUPCL(tty)) @@ -2974,10 +2985,7 @@ static void gsmtty_close(struct tty_struct *tty, struct file *filp) } tty_port_close_end(&dlci->port, tty); tty_port_tty_set(&dlci->port, NULL); -out: - dlci_put(dlci); - dlci_put(gsm->dlci[0]); - mux_put(gsm); + return; } static void gsmtty_hangup(struct tty_struct *tty) @@ -3154,6 +3162,16 @@ static int gsmtty_break_ctl(struct tty_struct *tty, int state) return gsmtty_modem_update(dlci, encode); } +static void gsmtty_remove(struct tty_driver *driver, struct tty_struct *tty) +{ + struct gsm_dlci *dlci = tty->driver_data; + struct gsm_mux *gsm = dlci->gsm; + + dlci_put(dlci); + dlci_put(gsm->dlci[0]); + mux_put(gsm); + driver->ttys[tty->index] = NULL; +} /* Virtual ttys for the demux */ static const struct tty_operations gsmtty_ops = { @@ -3173,6 +3191,7 @@ static const struct tty_operations gsmtty_ops = { .tiocmget = gsmtty_tiocmget, .tiocmset = gsmtty_tiocmset, .break_ctl = gsmtty_break_ctl, + .remove = gsmtty_remove, };