Commit de274bfe authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

TTY: introduce tty_port_destroy 



After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue.

Those using refcounting are safe now, but for those which do not we
introduce a function to be called right before the tty_port is freed
by the drivers.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 9a8e62bc

drivers/tty/tty_port.c

+15 −1
Original line number Diff line number Diff line
@@ -122,12 +122,26 @@ void tty_port_free_xmit_buf(struct tty_port *port) 
}

EXPORT_SYMBOL(tty_port_free_xmit_buf);



/**

 * tty_port_destroy -- destroy inited port

 * @port: tty port to be doestroyed

 *

 * When a port was initialized using tty_port_init, one has to destroy the

 * port by this function. Either indirectly by using tty_port refcounting

 * (tty_port_put) or directly if refcounting is not used.

 */

void tty_port_destroy(struct tty_port *port)

{

	tty_buffer_free_all(port);

}

EXPORT_SYMBOL(tty_port_destroy);



static void tty_port_destructor(struct kref *kref)

{

	struct tty_port *port = container_of(kref, struct tty_port, kref);

	if (port->xmit_buf)

		free_page((unsigned long)port->xmit_buf);

	tty_buffer_free_all(port);

	tty_port_destroy(port);

	if (port->ops && port->ops->destruct)

		port->ops->destruct(port);

	else

include/linux/tty.h

+1 −0
Original line number Diff line number Diff line
@@ -455,6 +455,7 @@ extern struct device *tty_port_register_device_attr(struct tty_port *port, 
		const struct attribute_group **attr_grp);

extern int tty_port_alloc_xmit_buf(struct tty_port *port);

extern void tty_port_free_xmit_buf(struct tty_port *port);

extern void tty_port_destroy(struct tty_port *port);

extern void tty_port_put(struct tty_port *port);



static inline struct tty_port *tty_port_get(struct tty_port *port)

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