[PATCH 01/33] tty: introduce and use tty_port_tty_vhangup() helper

[PATCH 01/33] tty: introduce and use tty_port_tty_vhangup() helper

[Jiri Slaby (SUSE)]

This code (tty_get -> vhangup -> tty_put) is repeated on few places.
Introduce a helper similar to tty_port_tty_hangup() (asynchronous) to
handle even vhangup (synchronous).

And use it on those places.

In fact, reuse the tty_port_tty_hangup()'s code and call tty_vhangup()
depending on a new bool parameter.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
---
Cc: netdev@vger.kernel.org
Cc: greybus-dev@lists.linaro.org
Cc: linux-staging@lists.linux.dev
Cc: linux-usb@vger.kernel.org
Cc: linux-bluetooth@vger.kernel.org
---
 drivers/isdn/capi/capi.c         |  8 +-------
 drivers/staging/greybus/uart.c   |  7 +------
 drivers/tty/serial/serial_core.c |  7 +------
 drivers/tty/tty_port.c           | 12 ++++++++----
 drivers/usb/class/cdc-acm.c      |  7 +------
 drivers/usb/serial/usb-serial.c  |  7 +------
 include/linux/tty_port.h         | 12 +++++++++++-
 net/bluetooth/rfcomm/tty.c       |  7 +------
 8 files changed, 25 insertions(+), 42 deletions(-)

diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c
index 70dee9ad4bae..78e6e7748fb9 100644
--- a/drivers/isdn/capi/capi.c
+++ b/drivers/isdn/capi/capi.c
@@ -306,15 +306,9 @@ static void capincci_alloc_minor(struct capidev *cdev, struct capincci *np)
 static void capincci_free_minor(struct capincci *np)
 {
 	struct capiminor *mp = np->minorp;
-	struct tty_struct *tty;
 
 	if (mp) {
-		tty = tty_port_tty_get(&mp->port);
-		if (tty) {
-			tty_vhangup(tty);
-			tty_kref_put(tty);
-		}
-
+		tty_port_tty_vhangup(&mp->port);
 		capiminor_free(mp);
 	}
 }
diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c
index 308ed1ca9947..10df5c37c83e 100644
--- a/drivers/staging/greybus/uart.c
+++ b/drivers/staging/greybus/uart.c
@@ -916,7 +916,6 @@ static void gb_uart_remove(struct gbphy_device *gbphy_dev)
 {
 	struct gb_tty *gb_tty = gb_gbphy_get_data(gbphy_dev);
 	struct gb_connection *connection = gb_tty->connection;
-	struct tty_struct *tty;
 	int ret;
 
 	ret = gbphy_runtime_get_sync(gbphy_dev);
@@ -929,11 +928,7 @@ static void gb_uart_remove(struct gbphy_device *gbphy_dev)
 	wake_up_all(&gb_tty->wioctl);
 	mutex_unlock(&gb_tty->mutex);
 
-	tty = tty_port_tty_get(&gb_tty->port);
-	if (tty) {
-		tty_vhangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_vhangup(&gb_tty->port);
 
 	gb_connection_disable_rx(connection);
 	tty_unregister_device(gb_tty_driver, gb_tty->minor);
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 1f7708a91fc6..d6485714eb0f 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -3209,7 +3209,6 @@ static void serial_core_remove_one_port(struct uart_driver *drv,
 	struct uart_state *state = drv->state + uport->line;
 	struct tty_port *port = &state->port;
 	struct uart_port *uart_port;
-	struct tty_struct *tty;
 
 	mutex_lock(&port->mutex);
 	uart_port = uart_port_check(state);
@@ -3228,11 +3227,7 @@ static void serial_core_remove_one_port(struct uart_driver *drv,
 	 */
 	tty_port_unregister_device(port, drv->tty_driver, uport->line);
 
-	tty = tty_port_tty_get(port);
-	if (tty) {
-		tty_vhangup(port->tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_vhangup(port);
 
 	/*
 	 * If the port is used as a console, unregister it
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 4af1fbf73f51..903eebdbe12d 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -396,15 +396,19 @@ EXPORT_SYMBOL(tty_port_hangup);
  * @port: tty port
  * @check_clocal: hang only ttys with %CLOCAL unset?
  */
-void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
+void __tty_port_tty_hangup(struct tty_port *port, bool check_clocal, bool async)
 {
 	struct tty_struct *tty = tty_port_tty_get(port);
 
-	if (tty && (!check_clocal || !C_CLOCAL(tty)))
-		tty_hangup(tty);
+	if (tty && (!check_clocal || !C_CLOCAL(tty))) {
+		if (async)
+			tty_hangup(tty);
+		else
+			tty_vhangup(tty);
+	}
 	tty_kref_put(tty);
 }
-EXPORT_SYMBOL_GPL(tty_port_tty_hangup);
+EXPORT_SYMBOL_GPL(__tty_port_tty_hangup);
 
 /**
  * tty_port_tty_wakeup - helper to wake up a tty
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index c2ecfa3c8349..f9171fbedf5c 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1571,7 +1571,6 @@ static int acm_probe(struct usb_interface *intf,
 static void acm_disconnect(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
-	struct tty_struct *tty;
 	int i;
 
 	/* sibling interface is already cleaning up */
@@ -1598,11 +1597,7 @@ static void acm_disconnect(struct usb_interface *intf)
 	usb_set_intfdata(acm->data, NULL);
 	mutex_unlock(&acm->mutex);
 
-	tty = tty_port_tty_get(&acm->port);
-	if (tty) {
-		tty_vhangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_vhangup(&acm->port);
 
 	cancel_delayed_work_sync(&acm->dwork);
 
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 7266558d823a..c78ff40b1e5f 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -1176,7 +1176,6 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 	struct usb_serial *serial = usb_get_intfdata(interface);
 	struct device *dev = &interface->dev;
 	struct usb_serial_port *port;
-	struct tty_struct *tty;
 
 	/* sibling interface is cleaning up */
 	if (!serial)
@@ -1191,11 +1190,7 @@ static void usb_serial_disconnect(struct usb_interface *interface)
 
 	for (i = 0; i < serial->num_ports; ++i) {
 		port = serial->port[i];
-		tty = tty_port_tty_get(&port->port);
-		if (tty) {
-			tty_vhangup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_vhangup(&port->port);
 		usb_serial_port_poison_urbs(port);
 		wake_up_interruptible(&port->port.delta_msr_wait);
 		cancel_work_sync(&port->work);
diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
index 08f89a598366..021f9a8415c0 100644
--- a/include/linux/tty_port.h
+++ b/include/linux/tty_port.h
@@ -232,7 +232,7 @@ bool tty_port_carrier_raised(struct tty_port *port);
 void tty_port_raise_dtr_rts(struct tty_port *port);
 void tty_port_lower_dtr_rts(struct tty_port *port);
 void tty_port_hangup(struct tty_port *port);
-void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
+void __tty_port_tty_hangup(struct tty_port *port, bool check_clocal, bool async);
 void tty_port_tty_wakeup(struct tty_port *port);
 int tty_port_block_til_ready(struct tty_port *port, struct tty_struct *tty,
 		struct file *filp);
@@ -251,4 +251,14 @@ static inline int tty_port_users(struct tty_port *port)
 	return port->count + port->blocked_open;
 }
 
+static inline void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
+{
+	__tty_port_tty_hangup(port, check_clocal, true);
+}
+
+static inline void tty_port_tty_vhangup(struct tty_port *port)
+{
+	__tty_port_tty_hangup(port, false, false);
+}
+
 #endif
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index 21a5b5535ebc..827dfbe66085 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -438,7 +438,6 @@ static int __rfcomm_release_dev(void __user *arg)
 {
 	struct rfcomm_dev_req req;
 	struct rfcomm_dev *dev;
-	struct tty_struct *tty;
 
 	if (copy_from_user(&req, arg, sizeof(req)))
 		return -EFAULT;
@@ -464,11 +463,7 @@ static int __rfcomm_release_dev(void __user *arg)
 		rfcomm_dlc_close(dev->dlc, 0);
 
 	/* Shut down TTY synchronously before freeing rfcomm_dev */
-	tty = tty_port_tty_get(&dev->port);
-	if (tty) {
-		tty_vhangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_vhangup(&dev->port);
 
 	if (!test_bit(RFCOMM_TTY_OWNED, &dev->status))
 		tty_port_put(&dev->port);
-- 
2.49.0

Re: [PATCH 01/33] tty: introduce and use tty_port_tty_vhangup() helper

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 8932 bytes --]

On Wed, 11 Jun 2025, Jiri Slaby (SUSE) wrote:

> This code (tty_get -> vhangup -> tty_put) is repeated on few places.
> Introduce a helper similar to tty_port_tty_hangup() (asynchronous) to
> handle even vhangup (synchronous).
> 
> And use it on those places.
> 
> In fact, reuse the tty_port_tty_hangup()'s code and call tty_vhangup()
> depending on a new bool parameter.
> 
> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
> Cc: Karsten Keil <isdn@linux-pingi.de>
> Cc: David Lin <dtwlin@gmail.com>
> Cc: Johan Hovold <johan@kernel.org>
> Cc: Alex Elder <elder@kernel.org>
> Cc: Oliver Neukum <oneukum@suse.com>
> Cc: Marcel Holtmann <marcel@holtmann.org>
> Cc: Johan Hedberg <johan.hedberg@gmail.com>
> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>

Nice cleanup. I'm not sure if it's important enough to be mentioned in
Documentation/driver-api/tty/tty_port.rst .

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

-- 
 i.

> ---
> Cc: netdev@vger.kernel.org
> Cc: greybus-dev@lists.linaro.org
> Cc: linux-staging@lists.linux.dev
> Cc: linux-usb@vger.kernel.org
> Cc: linux-bluetooth@vger.kernel.org

> ---
>  drivers/isdn/capi/capi.c         |  8 +-------
>  drivers/staging/greybus/uart.c   |  7 +------
>  drivers/tty/serial/serial_core.c |  7 +------
>  drivers/tty/tty_port.c           | 12 ++++++++----
>  drivers/usb/class/cdc-acm.c      |  7 +------
>  drivers/usb/serial/usb-serial.c  |  7 +------
>  include/linux/tty_port.h         | 12 +++++++++++-
>  net/bluetooth/rfcomm/tty.c       |  7 +------
>  8 files changed, 25 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c
> index 70dee9ad4bae..78e6e7748fb9 100644
> --- a/drivers/isdn/capi/capi.c
> +++ b/drivers/isdn/capi/capi.c
> @@ -306,15 +306,9 @@ static void capincci_alloc_minor(struct capidev *cdev, struct capincci *np)
>  static void capincci_free_minor(struct capincci *np)
>  {
>  	struct capiminor *mp = np->minorp;
> -	struct tty_struct *tty;
>  
>  	if (mp) {
> -		tty = tty_port_tty_get(&mp->port);
> -		if (tty) {
> -			tty_vhangup(tty);
> -			tty_kref_put(tty);
> -		}
> -
> +		tty_port_tty_vhangup(&mp->port);
>  		capiminor_free(mp);
>  	}
>  }
> diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c
> index 308ed1ca9947..10df5c37c83e 100644
> --- a/drivers/staging/greybus/uart.c
> +++ b/drivers/staging/greybus/uart.c
> @@ -916,7 +916,6 @@ static void gb_uart_remove(struct gbphy_device *gbphy_dev)
>  {
>  	struct gb_tty *gb_tty = gb_gbphy_get_data(gbphy_dev);
>  	struct gb_connection *connection = gb_tty->connection;
> -	struct tty_struct *tty;
>  	int ret;
>  
>  	ret = gbphy_runtime_get_sync(gbphy_dev);
> @@ -929,11 +928,7 @@ static void gb_uart_remove(struct gbphy_device *gbphy_dev)
>  	wake_up_all(&gb_tty->wioctl);
>  	mutex_unlock(&gb_tty->mutex);
>  
> -	tty = tty_port_tty_get(&gb_tty->port);
> -	if (tty) {
> -		tty_vhangup(tty);
> -		tty_kref_put(tty);
> -	}
> +	tty_port_tty_vhangup(&gb_tty->port);
>  
>  	gb_connection_disable_rx(connection);
>  	tty_unregister_device(gb_tty_driver, gb_tty->minor);
> diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
> index 1f7708a91fc6..d6485714eb0f 100644
> --- a/drivers/tty/serial/serial_core.c
> +++ b/drivers/tty/serial/serial_core.c
> @@ -3209,7 +3209,6 @@ static void serial_core_remove_one_port(struct uart_driver *drv,
>  	struct uart_state *state = drv->state + uport->line;
>  	struct tty_port *port = &state->port;
>  	struct uart_port *uart_port;
> -	struct tty_struct *tty;
>  
>  	mutex_lock(&port->mutex);
>  	uart_port = uart_port_check(state);
> @@ -3228,11 +3227,7 @@ static void serial_core_remove_one_port(struct uart_driver *drv,
>  	 */
>  	tty_port_unregister_device(port, drv->tty_driver, uport->line);
>  
> -	tty = tty_port_tty_get(port);
> -	if (tty) {
> -		tty_vhangup(port->tty);
> -		tty_kref_put(tty);
> -	}
> +	tty_port_tty_vhangup(port);
>  
>  	/*
>  	 * If the port is used as a console, unregister it
> diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
> index 4af1fbf73f51..903eebdbe12d 100644
> --- a/drivers/tty/tty_port.c
> +++ b/drivers/tty/tty_port.c
> @@ -396,15 +396,19 @@ EXPORT_SYMBOL(tty_port_hangup);
>   * @port: tty port
>   * @check_clocal: hang only ttys with %CLOCAL unset?
>   */
> -void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
> +void __tty_port_tty_hangup(struct tty_port *port, bool check_clocal, bool async)
>  {
>  	struct tty_struct *tty = tty_port_tty_get(port);
>  
> -	if (tty && (!check_clocal || !C_CLOCAL(tty)))
> -		tty_hangup(tty);
> +	if (tty && (!check_clocal || !C_CLOCAL(tty))) {
> +		if (async)
> +			tty_hangup(tty);
> +		else
> +			tty_vhangup(tty);
> +	}
>  	tty_kref_put(tty);
>  }
> -EXPORT_SYMBOL_GPL(tty_port_tty_hangup);
> +EXPORT_SYMBOL_GPL(__tty_port_tty_hangup);
>  
>  /**
>   * tty_port_tty_wakeup - helper to wake up a tty
> diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
> index c2ecfa3c8349..f9171fbedf5c 100644
> --- a/drivers/usb/class/cdc-acm.c
> +++ b/drivers/usb/class/cdc-acm.c
> @@ -1571,7 +1571,6 @@ static int acm_probe(struct usb_interface *intf,
>  static void acm_disconnect(struct usb_interface *intf)
>  {
>  	struct acm *acm = usb_get_intfdata(intf);
> -	struct tty_struct *tty;
>  	int i;
>  
>  	/* sibling interface is already cleaning up */
> @@ -1598,11 +1597,7 @@ static void acm_disconnect(struct usb_interface *intf)
>  	usb_set_intfdata(acm->data, NULL);
>  	mutex_unlock(&acm->mutex);
>  
> -	tty = tty_port_tty_get(&acm->port);
> -	if (tty) {
> -		tty_vhangup(tty);
> -		tty_kref_put(tty);
> -	}
> +	tty_port_tty_vhangup(&acm->port);
>  
>  	cancel_delayed_work_sync(&acm->dwork);
>  
> diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
> index 7266558d823a..c78ff40b1e5f 100644
> --- a/drivers/usb/serial/usb-serial.c
> +++ b/drivers/usb/serial/usb-serial.c
> @@ -1176,7 +1176,6 @@ static void usb_serial_disconnect(struct usb_interface *interface)
>  	struct usb_serial *serial = usb_get_intfdata(interface);
>  	struct device *dev = &interface->dev;
>  	struct usb_serial_port *port;
> -	struct tty_struct *tty;
>  
>  	/* sibling interface is cleaning up */
>  	if (!serial)
> @@ -1191,11 +1190,7 @@ static void usb_serial_disconnect(struct usb_interface *interface)
>  
>  	for (i = 0; i < serial->num_ports; ++i) {
>  		port = serial->port[i];
> -		tty = tty_port_tty_get(&port->port);
> -		if (tty) {
> -			tty_vhangup(tty);
> -			tty_kref_put(tty);
> -		}
> +		tty_port_tty_vhangup(&port->port);
>  		usb_serial_port_poison_urbs(port);
>  		wake_up_interruptible(&port->port.delta_msr_wait);
>  		cancel_work_sync(&port->work);
> diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
> index 08f89a598366..021f9a8415c0 100644
> --- a/include/linux/tty_port.h
> +++ b/include/linux/tty_port.h
> @@ -232,7 +232,7 @@ bool tty_port_carrier_raised(struct tty_port *port);
>  void tty_port_raise_dtr_rts(struct tty_port *port);
>  void tty_port_lower_dtr_rts(struct tty_port *port);
>  void tty_port_hangup(struct tty_port *port);
> -void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
> +void __tty_port_tty_hangup(struct tty_port *port, bool check_clocal, bool async);
>  void tty_port_tty_wakeup(struct tty_port *port);
>  int tty_port_block_til_ready(struct tty_port *port, struct tty_struct *tty,
>  		struct file *filp);
> @@ -251,4 +251,14 @@ static inline int tty_port_users(struct tty_port *port)
>  	return port->count + port->blocked_open;
>  }
>  
> +static inline void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
> +{
> +	__tty_port_tty_hangup(port, check_clocal, true);
> +}
> +
> +static inline void tty_port_tty_vhangup(struct tty_port *port)
> +{
> +	__tty_port_tty_hangup(port, false, false);
> +}
> +
>  #endif
> diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
> index 21a5b5535ebc..827dfbe66085 100644
> --- a/net/bluetooth/rfcomm/tty.c
> +++ b/net/bluetooth/rfcomm/tty.c
> @@ -438,7 +438,6 @@ static int __rfcomm_release_dev(void __user *arg)
>  {
>  	struct rfcomm_dev_req req;
>  	struct rfcomm_dev *dev;
> -	struct tty_struct *tty;
>  
>  	if (copy_from_user(&req, arg, sizeof(req)))
>  		return -EFAULT;
> @@ -464,11 +463,7 @@ static int __rfcomm_release_dev(void __user *arg)
>  		rfcomm_dlc_close(dev->dlc, 0);
>  
>  	/* Shut down TTY synchronously before freeing rfcomm_dev */
> -	tty = tty_port_tty_get(&dev->port);
> -	if (tty) {
> -		tty_vhangup(tty);
> -		tty_kref_put(tty);
> -	}
> +	tty_port_tty_vhangup(&dev->port);
>  
>  	if (!test_bit(RFCOMM_TTY_OWNED, &dev->status))
>  		tty_port_put(&dev->port);
> 

Re: [PATCH 01/33] tty: introduce and use tty_port_tty_vhangup() helper

[Jiri Slaby]

On 11. 06. 25, 13:13, Ilpo Järvinen wrote:
> On Wed, 11 Jun 2025, Jiri Slaby (SUSE) wrote:
> 
>> This code (tty_get -> vhangup -> tty_put) is repeated on few places.
>> Introduce a helper similar to tty_port_tty_hangup() (asynchronous) to
>> handle even vhangup (synchronous).
>>
>> And use it on those places.
>>
>> In fact, reuse the tty_port_tty_hangup()'s code and call tty_vhangup()
>> depending on a new bool parameter.
>>
>> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
>> Cc: Karsten Keil <isdn@linux-pingi.de>
>> Cc: David Lin <dtwlin@gmail.com>
>> Cc: Johan Hovold <johan@kernel.org>
>> Cc: Alex Elder <elder@kernel.org>
>> Cc: Oliver Neukum <oneukum@suse.com>
>> Cc: Marcel Holtmann <marcel@holtmann.org>
>> Cc: Johan Hedberg <johan.hedberg@gmail.com>
>> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
> 
> Nice cleanup. I'm not sure if it's important enough to be mentioned in
> Documentation/driver-api/tty/tty_port.rst .

At minimum I broke tty_port_tty_hangup()'s kernel-doc:
/**
  * tty_port_tty_hangup - helper to hang up a tty
  * @port: tty port
  * @check_clocal: hang only ttys with %CLOCAL unset?
  */
  void __tty_port_tty_hangup(struct tty_port *port, bool check_clocal, 
bool async)


doc says tty_port_tty_hangup(), code says __tty_port_tty_hangup(). Fix 
coming, incl. vhangup addition.

thanks,
-- 
js
suse labs