Re: [PATCH 5/9] Bluetooth: Fix incorrect setting of remote_tx_win for L2CAP ERTM.

["Gustavo F. Padovan" <gustavo@padovan.org>]

Hi Mat,

* Mat Martineau <mathewm@codeaurora.org> [2010-08-04 15:49:02 -0700]:

> remote_tx_win is intended to be set on receipt of an L2CAP
> configuration request.  The value is used to determine the size of the
> transmit window on the remote side of an ERTM connection, so L2CAP
> can stop sending frames when that remote window is full.
> 
> An incorrect remote_tx_win value will cause the stack to not fully
> utilize the tx window (performance impact), or to overfill the remote
> tx window (causing dropped frames or a disconnect).
> 
> This patch removes an extra setting of remote_tx_win when a
> configuration response is received.  The transmit window has a
> different meaning in a response - it is an informational value
> less than or equal to the local tx_win.
> 
> Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
> ---
>  net/bluetooth/l2cap.c |    1 -
>  1 files changed, 0 insertions(+), 1 deletions(-)
> 
> diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
> index 8cf9569..f0f3c7c 100644
> --- a/net/bluetooth/l2cap.c
> +++ b/net/bluetooth/l2cap.c
> @@ -2808,7 +2808,6 @@ static int l2cap_parse_conf_rsp(struct sock *sk, void *rsp, int len, void *data,
>  	if (*result == L2CAP_CONF_SUCCESS) {
>  		switch (rfc.mode) {
>  		case L2CAP_MODE_ERTM:
> -			pi->remote_tx_win   = rfc.txwin_size;
>  			pi->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
>  			pi->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
>  			pi->mps    = le16_to_cpu(rfc.max_pdu_size);

I agree. But you may also want to remove the same check inside
l2cap_conf_rfc_get() 

-- 
Gustavo F. Padovan
http://padovan.org