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authorAlan Cox <alan@linux.intel.com>2009-09-19 13:13:20 -0700
committerLive-CD User <linux@linux.site>2009-09-19 13:13:20 -0700
commit7ca0ff9ab3218ec443a7a9ad247e4650373ed41e (patch)
tree73cb5a8f36d9999e0c85957cc27e7be2f140a610
parent24d481ecae1614cf02e638c8dce9b6e8bf230603 (diff)
downloadop-kernel-dev-7ca0ff9ab3218ec443a7a9ad247e4650373ed41e.zip
op-kernel-dev-7ca0ff9ab3218ec443a7a9ad247e4650373ed41e.tar.gz
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 <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--drivers/char/tty_port.c29
-rw-r--r--include/linux/tty.h8
2 files changed, 34 insertions, 3 deletions
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);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index a916a31..ecb3d1b 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -187,7 +187,12 @@ struct tty_port;
struct tty_port_operations {
/* Return 1 if the carrier is raised */
int (*carrier_raised)(struct tty_port *port);
+ /* Control the DTR line */
void (*dtr_rts)(struct tty_port *port, int raise);
+ /* Called when the last close completes or a hangup finishes
+ IFF the port was initialized. Do not use to free resources */
+ void (*shutdown)(struct tty_port *port);
+ void (*drop)(struct tty_port *port);
};
struct tty_port {
@@ -459,7 +464,8 @@ extern int tty_port_block_til_ready(struct tty_port *port,
extern int tty_port_close_start(struct tty_port *port,
struct tty_struct *tty, struct file *filp);
extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
-
+extern void tty_port_close(struct tty_port *port,
+ struct tty_struct *tty, struct file *filp);
extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
extern int tty_unregister_ldisc(int disc);
extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
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