From 4c9fde9b860ccb27a7b026844eb3ef64c77e5a49 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Thu, 1 Oct 2009 14:54:46 +0200 Subject: USB: visor: fix trivial accounting bug in visor driver usb:usbserial:visor: fix accounting in error case data not pushed to the tty layer due to an error mustn't be counted Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/visor.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/usb/serial/visor.c') diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c index 1aa5d20a5d99..8e2d6dd9add0 100644 --- a/drivers/usb/serial/visor.c +++ b/drivers/usb/serial/visor.c @@ -513,7 +513,8 @@ static void visor_read_bulk_callback(struct urb *urb) tty_kref_put(tty); } spin_lock(&priv->lock); - priv->bytes_in += available_room; + if (tty) + priv->bytes_in += available_room; } else { spin_lock(&priv->lock); -- cgit v1.2.2 From 638325154572ba2113a18669fe3b299caa2dabd9 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Wed, 7 Oct 2009 10:50:23 +0200 Subject: USB: serial: fix assumption that throttle/unthrottle cannot sleep many serial subdrivers are clearly written as if throttle/unthrottle cannot sleep. This leads to unneeded atomic submissions. This patch converts affected drivers in a way to makes very clear that throttle/unthrottle can sleep. Thus future misdesigns can be avoided and efficiency and reliability improved. This removes any such assumption using GFP_KERNEL and spin_lock_irq() Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/visor.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'drivers/usb/serial/visor.c') diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c index 8e2d6dd9add0..b9341f0e452b 100644 --- a/drivers/usb/serial/visor.c +++ b/drivers/usb/serial/visor.c @@ -583,12 +583,11 @@ static void visor_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct visor_private *priv = usb_get_serial_port_data(port); - unsigned long flags; dbg("%s - port %d", __func__, port->number); - spin_lock_irqsave(&priv->lock, flags); + spin_lock_irq(&priv->lock); priv->throttled = 1; - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); } @@ -596,17 +595,16 @@ static void visor_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct visor_private *priv = usb_get_serial_port_data(port); - unsigned long flags; int result; dbg("%s - port %d", __func__, port->number); - spin_lock_irqsave(&priv->lock, flags); + spin_lock_irq(&priv->lock); priv->throttled = 0; priv->actually_throttled = 0; - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); port->read_urb->dev = port->serial->dev; - result = usb_submit_urb(port->read_urb, GFP_ATOMIC); + result = usb_submit_urb(port->read_urb, GFP_KERNEL); if (result) dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", -- cgit v1.2.2 From a1c33952b729eba4cedb8dbe54765921f2b3062f Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Wed, 7 Oct 2009 11:01:38 +0200 Subject: USB: serial: fix race between unthrottle and completion handler in visor usb:usbserial:visor: fix race between unthrottle and completion handler visor_unthrottle() mustn't resubmit the URB unconditionally as the URB may still be running. the same bug as opticon. Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/visor.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'drivers/usb/serial/visor.c') diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c index b9341f0e452b..ad1f9232292d 100644 --- a/drivers/usb/serial/visor.c +++ b/drivers/usb/serial/visor.c @@ -595,20 +595,23 @@ static void visor_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct visor_private *priv = usb_get_serial_port_data(port); - int result; + int result, was_throttled; dbg("%s - port %d", __func__, port->number); spin_lock_irq(&priv->lock); priv->throttled = 0; + was_throttled = priv->actually_throttled; priv->actually_throttled = 0; spin_unlock_irq(&priv->lock); - port->read_urb->dev = port->serial->dev; - result = usb_submit_urb(port->read_urb, GFP_KERNEL); - if (result) - dev_err(&port->dev, - "%s - failed submitting read urb, error %d\n", + if (was_throttled) { + port->read_urb->dev = port->serial->dev; + result = usb_submit_urb(port->read_urb, GFP_KERNEL); + if (result) + dev_err(&port->dev, + "%s - failed submitting read urb, error %d\n", __func__, result); + } } static int palm_os_3_probe(struct usb_serial *serial, -- cgit v1.2.2