From: Alan Cox Date: Fri, 2 Jan 2009 13:47:32 +0000 (+0000) Subject: tty: kref nozomi X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=33dd474a;p=linux-beck.git tty: kref nozomi Update the nozomi driver to use krefs Signed-off-by: Linus Torvalds --- diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c index 9a34a1935283..d6102b644b55 100644 --- a/drivers/char/nozomi.c +++ b/drivers/char/nozomi.c @@ -353,6 +353,7 @@ struct ctrl_ul { /* This holds all information that is needed regarding a port */ struct port { + struct tty_port port; u8 update_flow_control; struct ctrl_ul ctrl_ul; struct ctrl_dl ctrl_dl; @@ -365,8 +366,6 @@ struct port { u8 toggle_ul; u16 token_dl; - struct tty_struct *tty; - int tty_open_count; /* mutex to ensure one access patch to this port */ struct mutex tty_sem; wait_queue_head_t tty_wait; @@ -788,14 +787,14 @@ static void disable_transmit_dl(enum port_type port, struct nozomi *dc) * Return 1 - send buffer to card and ack. * Return 0 - don't ack, don't send buffer to card. */ -static int send_data(enum port_type index, const struct nozomi *dc) +static int send_data(enum port_type index, struct nozomi *dc) { u32 size = 0; - const struct port *port = &dc->port[index]; + struct port *port = &dc->port[index]; const u8 toggle = port->toggle_ul; void __iomem *addr = port->ul_addr[toggle]; const u32 ul_size = port->ul_size[toggle]; - struct tty_struct *tty = port->tty; + struct tty_struct *tty = tty_port_tty_get(&port->port); /* Get data from tty and place in buf for now */ size = __kfifo_get(port->fifo_ul, dc->send_buf, @@ -803,6 +802,7 @@ static int send_data(enum port_type index, const struct nozomi *dc) if (size == 0) { DBG4("No more data to send, disable link:"); + tty_kref_put(tty); return 0; } @@ -815,6 +815,7 @@ static int send_data(enum port_type index, const struct nozomi *dc) if (tty) tty_wakeup(tty); + tty_kref_put(tty); return 1; } @@ -826,7 +827,7 @@ static int receive_data(enum port_type index, struct nozomi *dc) u32 offset = 4; struct port *port = &dc->port[index]; void __iomem *addr = port->dl_addr[port->toggle_dl]; - struct tty_struct *tty = port->tty; + struct tty_struct *tty = tty_port_tty_get(&port->port); int i; if (unlikely(!tty)) { @@ -870,7 +871,7 @@ static int receive_data(enum port_type index, struct nozomi *dc) } set_bit(index, &dc->flip); - + tty_kref_put(tty); return 1; } @@ -1276,9 +1277,15 @@ static irqreturn_t interrupt_handler(int irq, void *dev_id) exit_handler: spin_unlock(&dc->spin_mutex); - for (a = 0; a < NOZOMI_MAX_PORTS; a++) - if (test_and_clear_bit(a, &dc->flip)) - tty_flip_buffer_push(dc->port[a].tty); + for (a = 0; a < NOZOMI_MAX_PORTS; a++) { + struct tty_struct *tty; + if (test_and_clear_bit(a, &dc->flip)) { + tty = tty_port_tty_get(&dc->port[a].port); + if (tty) + tty_flip_buffer_push(tty); + tty_kref_put(tty); + } + } return IRQ_HANDLED; none: spin_unlock(&dc->spin_mutex); @@ -1453,12 +1460,10 @@ static int __devinit nozomi_card_init(struct pci_dev *pdev, for (i = 0; i < MAX_PORT; i++) { mutex_init(&dc->port[i].tty_sem); - dc->port[i].tty_open_count = 0; - dc->port[i].tty = NULL; + tty_port_init(&dc->port[i].port); tty_register_device(ntty_driver, dc->index_start + i, &pdev->dev); } - return 0; err_free_sbuf: @@ -1482,14 +1487,16 @@ static void __devexit tty_exit(struct nozomi *dc) flush_scheduled_work(); - for (i = 0; i < MAX_PORT; ++i) - if (dc->port[i].tty && \ - list_empty(&dc->port[i].tty->hangup_work.entry)) - tty_hangup(dc->port[i].tty); - + for (i = 0; i < MAX_PORT; ++i) { + struct tty_struct *tty = tty_port_tty_get(&dc->port[i].port); + if (tty && list_empty(&tty->hangup_work.entry)) + tty_hangup(tty); + tty_kref_put(tty); + } + /* Racy below - surely should wait for scheduled work to be done or + complete off a hangup method ? */ while (dc->open_ttys) msleep(1); - for (i = dc->index_start; i < dc->index_start + MAX_PORT; ++i) tty_unregister_device(ntty_driver, i); } @@ -1579,23 +1586,22 @@ static int ntty_open(struct tty_struct *tty, struct file *file) if (mutex_lock_interruptible(&port->tty_sem)) return -ERESTARTSYS; - port->tty_open_count++; + port->port.count++; dc->open_ttys++; /* Enable interrupt downlink for channel */ - if (port->tty_open_count == 1) { + if (port->port.count == 1) { + /* FIXME: is this needed now ? */ tty->low_latency = 1; tty->driver_data = port; - port->tty = tty; + tty_port_tty_set(&port->port, tty); DBG1("open: %d", port->token_dl); spin_lock_irqsave(&dc->spin_mutex, flags); dc->last_ier = dc->last_ier | port->token_dl; writew(dc->last_ier, dc->reg_ier); spin_unlock_irqrestore(&dc->spin_mutex, flags); } - mutex_unlock(&port->tty_sem); - return 0; } @@ -1606,31 +1612,30 @@ static int ntty_open(struct tty_struct *tty, struct file *file) static void ntty_close(struct tty_struct *tty, struct file *file) { struct nozomi *dc = get_dc_by_tty(tty); - struct port *port = tty->driver_data; + struct port *nport = tty->driver_data; + struct tty_port *port = &nport->port; unsigned long flags; - if (!dc || !port) + if (!dc || !nport) return; - if (mutex_lock_interruptible(&port->tty_sem)) - return; + /* Users cannot interrupt a close */ + mutex_lock(&nport->tty_sem); - if (!port->tty_open_count) - goto exit; + WARN_ON(!port->count); dc->open_ttys--; - port->tty_open_count--; + port->count--; + tty_port_tty_set(port, NULL); - if (port->tty_open_count == 0) { - DBG1("close: %d", port->token_dl); + if (port->count == 0) { + DBG1("close: %d", nport->token_dl); spin_lock_irqsave(&dc->spin_mutex, flags); - dc->last_ier &= ~(port->token_dl); + dc->last_ier &= ~(nport->token_dl); writew(dc->last_ier, dc->reg_ier); spin_unlock_irqrestore(&dc->spin_mutex, flags); } - -exit: - mutex_unlock(&port->tty_sem); + mutex_unlock(&nport->tty_sem); } /* @@ -1660,7 +1665,7 @@ static int ntty_write(struct tty_struct *tty, const unsigned char *buffer, return -EAGAIN; } - if (unlikely(!port->tty_open_count)) { + if (unlikely(!port->port.count)) { DBG1(" "); goto exit; } @@ -1710,7 +1715,7 @@ static int ntty_write_room(struct tty_struct *tty) if (!mutex_trylock(&port->tty_sem)) return 0; - if (!port->tty_open_count) + if (!port->port.count) goto exit; room = port->fifo_ul->size - __kfifo_len(port->fifo_ul); @@ -1866,7 +1871,7 @@ static s32 ntty_chars_in_buffer(struct tty_struct *tty) goto exit_in_buffer; } - if (unlikely(!port->tty_open_count)) { + if (unlikely(!port->port.count)) { dev_err(&dc->pdev->dev, "No tty open?\n"); rval = -ENODEV; goto exit_in_buffer;