Return-Path: From: Gianluca Anzolin To: gustavo@padovan.org Cc: linux-bluetooth@vger.kernel.org, peter@hurleysoftware.com, marcel@holtmann.org, Gianluca Anzolin Subject: [PATCH 4/8] Move tty initialization and cleanup out of open/close Date: Fri, 12 Jul 2013 22:40:44 +0200 Message-Id: <1373661649-1385-4-git-send-email-gianluca@sottospazio.it> In-Reply-To: <1373661649-1385-1-git-send-email-gianluca@sottospazio.it> References: <1373661649-1385-1-git-send-email-gianluca@sottospazio.it> List-ID: Move the tty initialization from rfcomm_tty_open to rfcomm_tty_install and do the same for the cleanup moving the code from rfcomm_tty_close to rfcomm_tty_cleanup. Signed-off-by: Gianluca Anzolin --- net/bluetooth/rfcomm/tty.c | 82 +++++++++++++++++++++++++++------------------- 1 file changed, 49 insertions(+), 33 deletions(-) diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c index 9b0b064..c1dd55d 100644 --- a/net/bluetooth/rfcomm/tty.c +++ b/net/bluetooth/rfcomm/tty.c @@ -717,10 +717,55 @@ static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig) } /* ---- TTY functions ---- */ +/* + * here we acquire the tty_port reference since it's here the tty is first used + * by setting the termios. We also populate the driver_data field and install + * the tty_port. + */ +static int rfcomm_tty_install(struct tty_driver *driver, struct tty_struct *tty) +{ + struct rfcomm_dev *dev; + int err; + + dev = rfcomm_dev_get(tty->index); + if (!dev) + return -ENODEV; + + /* Attach TTY */ + rfcomm_dlc_lock(dev->dlc); + tty->driver_data = dev; + rfcomm_dlc_unlock(dev->dlc); + set_bit(RFCOMM_TTY_ATTACHED, &dev->flags); + + err = tty_port_install(&dev->port, driver, tty); + if (err < 0) { + clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags); + tty_port_put(&dev->port); + } + + return err; +} + +/* + * here we do the reverse, by clearing the tty fields and releasing + * the reference to tty_port. + */ +static void rfcomm_tty_cleanup(struct tty_struct *tty) +{ + struct rfcomm_dev *dev = tty->driver_data; + + /* Remove driver data */ + clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags); + rfcomm_dlc_lock(dev->dlc); + tty->driver_data = NULL; + rfcomm_dlc_unlock(dev->dlc); + + tty_port_put(&dev->port); +} + static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp) { - struct rfcomm_dev *dev; - struct rfcomm_dlc *dlc; + struct rfcomm_dev *dev = tty->driver_data; unsigned long flags; int id; @@ -728,14 +773,6 @@ static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp) BT_DBG("tty %p id %d", tty, id); - /* We don't leak this refcount. For reasons which are not entirely - clear, the TTY layer will call our ->close() method even if the - open fails. We decrease the refcount there, and decreasing it - here too would cause breakage. */ - dev = rfcomm_dev_get(id); - if (!dev) - return -ENODEV; - BT_DBG("dev %p dst %pMR channel %d opened %d", dev, &dev->dst, dev->channel, dev->port.count); @@ -746,16 +783,6 @@ static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp) } spin_unlock_irqrestore(&dev->port.lock, flags); - dlc = dev->dlc; - - /* Attach TTY and open DLC */ - - rfcomm_dlc_lock(dlc); - tty->driver_data = dev; - tty_port_tty_set(&dev->port, tty); - rfcomm_dlc_unlock(dlc); - set_bit(RFCOMM_TTY_ATTACHED, &dev->flags); - return 0; } @@ -764,9 +791,6 @@ static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp) struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data; unsigned long flags; - if (!dev) - return; - BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc, dev->port.count); @@ -774,14 +798,6 @@ static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp) if (!--dev->port.count) { spin_unlock_irqrestore(&dev->port.lock, flags); - /* detach the TTY */ - clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags); - - rfcomm_dlc_lock(dev->dlc); - tty->driver_data = NULL; - tty_port_tty_set(&dev->port, NULL); - rfcomm_dlc_unlock(dev->dlc); - if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) { spin_lock(&rfcomm_dev_lock); list_del_init(&dev->list); @@ -791,8 +807,6 @@ static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp) } } else spin_unlock_irqrestore(&dev->port.lock, flags); - - tty_port_put(&dev->port); } static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count) @@ -1165,6 +1179,8 @@ static const struct tty_operations rfcomm_ops = { .wait_until_sent = rfcomm_tty_wait_until_sent, .tiocmget = rfcomm_tty_tiocmget, .tiocmset = rfcomm_tty_tiocmset, + .install = rfcomm_tty_install, + .cleanup = rfcomm_tty_cleanup, }; int __init rfcomm_init_ttys(void) -- 1.8.3.2