From 7ca0ff9ab3218ec443a7a9ad247e4650373ed41e Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Sat, 19 Sep 2009 13:13:20 -0700 Subject: tty: Add a full port_close function Now we are extracting out methods for shutdown and the like we can add a proper tty_port_close method that knows all the innards of the tty closing process and hides the lot from the caller. At some point in the future this will be paired with a similar open() helper and the drivers can stick to hardware management. Signed-off-by: Alan Cox Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/char/tty_port.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c index 9769b11..549bd0f 100644 --- a/drivers/char/tty_port.c +++ b/drivers/char/tty_port.c @@ -96,6 +96,14 @@ void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty) } EXPORT_SYMBOL(tty_port_tty_set); +static void tty_port_shutdown(struct tty_port *port) +{ + if (port->ops->shutdown && + test_and_clear_bit(ASYNC_INITIALIZED, &port->flags)) + port->ops->shutdown(port); + +} + /** * tty_port_hangup - hangup helper * @port: tty port @@ -116,6 +124,7 @@ void tty_port_hangup(struct tty_port *port) port->tty = NULL; spin_unlock_irqrestore(&port->lock, flags); wake_up_interruptible(&port->open_wait); + tty_port_shutdown(port); } EXPORT_SYMBOL(tty_port_hangup); @@ -296,15 +305,17 @@ int tty_port_close_start(struct tty_port *port, struct tty_struct *tty, struct f if (port->count) { spin_unlock_irqrestore(&port->lock, flags); + if (port->ops->drop) + port->ops->drop(port); return 0; } - port->flags |= ASYNC_CLOSING; + set_bit(ASYNC_CLOSING, &port->flags); tty->closing = 1; spin_unlock_irqrestore(&port->lock, flags); /* Don't block on a stalled port, just pull the chain */ if (tty->flow_stopped) tty_driver_flush_buffer(tty); - if (port->flags & ASYNC_INITIALIZED && + if (test_bit(ASYNCB_INITIALIZED, &port->flags) && port->closing_wait != ASYNC_CLOSING_WAIT_NONE) tty_wait_until_sent(tty, port->closing_wait); if (port->drain_delay) { @@ -318,6 +329,9 @@ int tty_port_close_start(struct tty_port *port, struct tty_struct *tty, struct f timeout = 2 * HZ; schedule_timeout_interruptible(timeout); } + /* Don't call port->drop for the last reference. Callers will want + to drop the last active reference in ->shutdown() or the tty + shutdown path */ return 1; } EXPORT_SYMBOL(tty_port_close_start); @@ -348,3 +362,14 @@ void tty_port_close_end(struct tty_port *port, struct tty_struct *tty) spin_unlock_irqrestore(&port->lock, flags); } EXPORT_SYMBOL(tty_port_close_end); + +void tty_port_close(struct tty_port *port, struct tty_struct *tty, + struct file *filp) +{ + if (tty_port_close_start(port, tty, filp) == 0) + return; + tty_port_shutdown(port); + tty_port_close_end(port, tty); + tty_port_tty_set(port, NULL); +} +EXPORT_SYMBOL(tty_port_close); -- cgit v1.1