USB: serial: fix generic chars_in_buffer

Make sure chars_in_buffer accounts also for data in host stack queues.

This fixes the problem with tty_wait_until_sent returning too soon at
close which could cause the final write urb to be cancelled.

Reported-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Johan Hovold 2010-03-17 23:00:42 +01:00 committed by Greg Kroah-Hartman
parent 7919c2fd9e
commit 30af7fb5a4

View file

@ -309,10 +309,14 @@ static int usb_serial_generic_write_start(struct usb_serial_port *port)
/* don't have to grab the lock here, as we will /* don't have to grab the lock here, as we will
retry if != 0 */ retry if != 0 */
port->write_urb_busy = 0; port->write_urb_busy = 0;
} else return result;
result = count; }
return result; spin_lock_irqsave(&port->lock, flags);
port->tx_bytes_flight += count;
spin_unlock_irqrestore(&port->lock, flags);
return count;
} }
/** /**
@ -400,7 +404,7 @@ int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
if (serial->type->max_in_flight_urbs) if (serial->type->max_in_flight_urbs)
chars = port->tx_bytes_flight; chars = port->tx_bytes_flight;
else else
chars = kfifo_len(&port->write_fifo); chars = kfifo_len(&port->write_fifo) + port->tx_bytes_flight;
spin_unlock_irqrestore(&port->lock, flags); spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, chars); dbg("%s - returns %d", __func__, chars);
@ -510,7 +514,10 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
port->urbs_in_flight = 0; port->urbs_in_flight = 0;
spin_unlock_irqrestore(&port->lock, flags); spin_unlock_irqrestore(&port->lock, flags);
} else { } else {
spin_lock_irqsave(&port->lock, flags);
port->tx_bytes_flight -= urb->transfer_buffer_length;
port->write_urb_busy = 0; port->write_urb_busy = 0;
spin_unlock_irqrestore(&port->lock, flags);
if (status) if (status)
kfifo_reset_out(&port->write_fifo); kfifo_reset_out(&port->write_fifo);