Fix usb_serial_probe() problem introduced by the recent kfifo changes

The USB serial code was a new user of the kfifo API, and it was missed
when porting things to the new kfifo API.

Please make the write_fifo in place.  Here is my patch to fix the
regression and full ported version.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Reported-and-tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 8 insertions, 9 deletions

diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index b0f1183755c9..f1ea3a33b6e6 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -276,7 +276,7 @@ static int usb_serial_generic_write_start(struct usb_serial_port *port)
         if (port->write_urb_busy)
                 start_io = false;
         else {
-                start_io = (kfifo_len(port->write_fifo) != 0);
+                start_io = (kfifo_len(&port->write_fifo) != 0);
                 port->write_urb_busy = start_io;
         }
         spin_unlock_irqrestore(&port->lock, flags);
@@ -285,7 +285,7 @@ static int usb_serial_generic_write_start(struct usb_serial_port *port)
                 return 0;
 
         data = port->write_urb->transfer_buffer;
-        count = kfifo_out_locked(port->write_fifo, data, port->bulk_out_size, &port->lock);
+        count = kfifo_out_locked(&port->write_fifo, data, port->bulk_out_size, &port->lock);
         usb_serial_debug_data(debug, &port->dev, __func__, count, data);
 
         /* set up our urb */
@@ -345,7 +345,7 @@ int usb_serial_generic_write(struct tty_struct *tty,
                 return usb_serial_multi_urb_write(tty, port,
                                                   buf, count);
 
-        count = kfifo_in_locked(port->write_fifo, buf, count, &port->lock);
+        count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
         result = usb_serial_generic_write_start(port);
 
         if (result >= 0)
@@ -370,7 +370,7 @@ int usb_serial_generic_write_room(struct tty_struct *tty)
                                 (serial->type->max_in_flight_urbs -
                                  port->urbs_in_flight);
         } else if (serial->num_bulk_out)
-                room = port->write_fifo->size - kfifo_len(port->write_fifo);
+                room = kfifo_avail(&port->write_fifo);
         spin_unlock_irqrestore(&port->lock, flags);
 
         dbg("%s - returns %d", __func__, room);
@@ -391,7 +391,7 @@ int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
                 chars = port->tx_bytes_flight;
                 spin_unlock_irqrestore(&port->lock, flags);
         } else if (serial->num_bulk_out)
-                chars = kfifo_len(port->write_fifo);
+                chars = kfifo_len(&port->write_fifo);
 
         dbg("%s - returns %d", __func__, chars);
         return chars;
@@ -507,7 +507,7 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
                 if (status) {
                         dbg("%s - nonzero multi-urb write bulk status "
                                 "received: %d", __func__, status);
-                        kfifo_reset(port->write_fifo);
+                        kfifo_reset_out(&port->write_fifo);
                 } else
                         usb_serial_generic_write_start(port);
         }
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 636a4f23445e..33c85f7084f8 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -595,8 +595,7 @@ static void port_release(struct device *dev)
         usb_free_urb(port->write_urb);
         usb_free_urb(port->interrupt_in_urb);
         usb_free_urb(port->interrupt_out_urb);
-        if (!IS_ERR(port->write_fifo) && port->write_fifo)
-                kfifo_free(port->write_fifo);
+        kfifo_free(&port->write_fifo);
         kfree(port->bulk_in_buffer);
         kfree(port->bulk_out_buffer);
         kfree(port->interrupt_in_buffer);
@@ -939,7 +938,7 @@ int usb_serial_probe(struct usb_interface *interface,
                         dev_err(&interface->dev, "No free urbs available\n");
                         goto probe_error;
                 }
-                if (kfifo_alloc(port->write_fifo, PAGE_SIZE, GFP_KERNEL))
+                if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
                         goto probe_error;
                 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
                 port->bulk_out_size = buffer_size;