diff options
Diffstat (limited to 'drivers/usb/serial/usb-serial.c')
| -rw-r--r-- | drivers/usb/serial/usb-serial.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index 794b5ffe4397..080ade223d53 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -269,15 +269,19 @@ static void serial_close(struct tty_struct *tty, struct file *filp) return; } - --port->port.count; - if (port->port.count == 0) + if (port->port.count == 1) /* only call the device specific close if this - * port is being closed by the last owner */ + * port is being closed by the last owner. Ensure we do + * this before we drop the port count. The call is protected + * by the port mutex + */ port->serial->type->close(tty, port, filp); - if (port->port.count == (port->console? 1 : 0)) { + if (port->port.count == (port->console ? 2 : 1)) { struct tty_struct *tty = tty_port_tty_get(&port->port); if (tty) { + /* We must do this before we drop the port count to + zero. */ if (tty->driver_data) tty->driver_data = NULL; tty_port_tty_set(&port->port, NULL); @@ -285,13 +289,14 @@ static void serial_close(struct tty_struct *tty, struct file *filp) } } - if (port->port.count == 0) { + if (port->port.count == 1) { mutex_lock(&port->serial->disc_mutex); if (!port->serial->disconnected) usb_autopm_put_interface(port->serial->interface); mutex_unlock(&port->serial->disc_mutex); module_put(port->serial->type->driver.owner); } + --port->port.count; mutex_unlock(&port->mutex); usb_serial_put(port->serial); @@ -334,6 +339,10 @@ static int serial_chars_in_buffer(struct tty_struct *tty) dbg("%s = port %d", __func__, port->number); WARN_ON(!port->port.count); + /* if the device was unplugged then any remaining characters + fell out of the connector ;) */ + if (port->serial->disconnected) + return 0; /* pass on to the driver specific version of this function */ return port->serial->type->chars_in_buffer(tty); } @@ -373,9 +382,7 @@ static int serial_ioctl(struct tty_struct *tty, struct file *file, /* pass on to the driver specific version of this function if it is available */ if (port->serial->type->ioctl) { - lock_kernel(); retval = port->serial->type->ioctl(tty, file, cmd, arg); - unlock_kernel(); } else retval = -ENOIOCTLCMD; return retval; @@ -404,11 +411,8 @@ static int serial_break(struct tty_struct *tty, int break_state) WARN_ON(!port->port.count); /* pass on to the driver specific version of this function if it is available */ - if (port->serial->type->break_ctl) { - lock_kernel(); + if (port->serial->type->break_ctl) port->serial->type->break_ctl(tty, break_state); - unlock_kernel(); - } return 0; } |