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-rw-r--r--drivers/char/tty_io.c15
-rw-r--r--drivers/usb/serial/usb-serial.c14
-rw-r--r--include/linux/tty_driver.h13
3 files changed, 27 insertions, 15 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index ea18a12..59499ee 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -1389,7 +1389,7 @@ EXPORT_SYMBOL(tty_shutdown);
* of ttys that the driver keeps.
*
* This method gets called from a work queue so that the driver private
- * shutdown ops can sleep (needed for USB at least)
+ * cleanup ops can sleep (needed for USB at least)
*/
static void release_one_tty(struct work_struct *work)
{
@@ -1397,10 +1397,9 @@ static void release_one_tty(struct work_struct *work)
container_of(work, struct tty_struct, hangup_work);
struct tty_driver *driver = tty->driver;
- if (tty->ops->shutdown)
- tty->ops->shutdown(tty);
- else
- tty_shutdown(tty);
+ if (tty->ops->cleanup)
+ tty->ops->cleanup(tty);
+
tty->magic = 0;
tty_driver_kref_put(driver);
module_put(driver->owner);
@@ -1415,6 +1414,12 @@ static void release_one_tty(struct work_struct *work)
static void queue_release_one_tty(struct kref *kref)
{
struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
+
+ if (tty->ops->shutdown)
+ tty->ops->shutdown(tty);
+ else
+ tty_shutdown(tty);
+
/* The hangup queue is now free so we can reuse it rather than
waste a chunk of memory for each port */
INIT_WORK(&tty->hangup_work, release_one_tty);
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index ff75a35..aa6b2ae 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -192,7 +192,7 @@ void usb_serial_put(struct usb_serial *serial)
* This is the first place a new tty gets used. Hence this is where we
* acquire references to the usb_serial structure and the driver module,
* where we store a pointer to the port, and where we do an autoresume.
- * All these actions are reversed in serial_release().
+ * All these actions are reversed in serial_cleanup().
*/
static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
{
@@ -339,15 +339,16 @@ static void serial_close(struct tty_struct *tty, struct file *filp)
}
/**
- * serial_release - free resources post close/hangup
+ * serial_cleanup - free resources post close/hangup
* @port: port to free up
*
* Do the resource freeing and refcount dropping for the port.
* Avoid freeing the console.
*
- * Called when the last tty kref is dropped.
+ * Called asynchronously after the last tty kref is dropped,
+ * and the tty layer has already done the tty_shutdown(tty);
*/
-static void serial_release(struct tty_struct *tty)
+static void serial_cleanup(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial;
@@ -361,9 +362,6 @@ static void serial_release(struct tty_struct *tty)
dbg("%s - port %d", __func__, port->number);
- /* Standard shutdown processing */
- tty_shutdown(tty);
-
tty->driver_data = NULL;
serial = port->serial;
@@ -1210,7 +1208,7 @@ static const struct tty_operations serial_ops = {
.chars_in_buffer = serial_chars_in_buffer,
.tiocmget = serial_tiocmget,
.tiocmset = serial_tiocmset,
- .shutdown = serial_release,
+ .cleanup = serial_cleanup,
.install = serial_install,
.proc_fops = &serial_proc_fops,
};
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index 3566129..b086779 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -45,8 +45,16 @@
*
* void (*shutdown)(struct tty_struct * tty);
*
- * This routine is called when a particular tty device is closed for
- * the last time freeing up the resources.
+ * This routine is called synchronously when a particular tty device
+ * is closed for the last time freeing up the resources.
+ *
+ *
+ * void (*cleanup)(struct tty_struct * tty);
+ *
+ * This routine is called asynchronously when a particular tty device
+ * is closed for the last time freeing up the resources. This is
+ * actually the second part of shutdown for routines that might sleep.
+ *
*
* int (*write)(struct tty_struct * tty,
* const unsigned char *buf, int count);
@@ -233,6 +241,7 @@ struct tty_operations {
int (*open)(struct tty_struct * tty, struct file * filp);
void (*close)(struct tty_struct * tty, struct file * filp);
void (*shutdown)(struct tty_struct *tty);
+ void (*cleanup)(struct tty_struct *tty);
int (*write)(struct tty_struct * tty,
const unsigned char *buf, int count);
int (*put_char)(struct tty_struct *tty, unsigned char ch);
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