RE: [PATCH 1/4] Bluetooth: Add sockopt configuration for txWindow on L2CAP

["Mat Martineau" <mathewm@codeaurora.org>]

Gustavo -

> -----Original Message-----
> From: linux-bluetooth-owner@vger.kernel.org [mailto:linux-bluetooth-
> owner@vger.kernel.org] On Behalf Of Gustavo F. Padovan
> Sent: Monday, March 15, 2010 5:26 PM
> To: linux-bluetooth@vger.kernel.org
> Cc: marcel@holtmann.org; gustavo@padovan.org
> Subject: [PATCH 1/4] Bluetooth: Add sockopt configuration for txWindow
> on L2CAP
> 
> Now can set/get Transmission Window size via sockopt.

It would be better to use __u16 for the Tx Window size, so we can use
extended window sizes in the future.  This is important for AMP, where the
amount of data in-flight can be large enough for the extended Tx Window to
matter.

> 
> Signed-off-by: Gustavo F. Padovan <gustavo@padovan.org>
> ---
>  include/net/bluetooth/l2cap.h |    2 ++
>  net/bluetooth/l2cap.c         |    7 ++++++-
>  2 files changed, 8 insertions(+), 1 deletions(-)
> 
> diff --git a/include/net/bluetooth/l2cap.h
> b/include/net/bluetooth/l2cap.h
> index 48f10f4..c7bf676 100644
> --- a/include/net/bluetooth/l2cap.h
> +++ b/include/net/bluetooth/l2cap.h
> @@ -56,6 +56,7 @@ struct l2cap_options {
>  	__u16 flush_to;
>  	__u8  mode;
>  	__u8  fcs;
> +	__u8  txwin_size;
>  };
> 
>  #define L2CAP_CONNINFO	0x02
> @@ -339,6 +340,7 @@ struct l2cap_pinfo {
> 
>  	__u8		ident;
> 
> +	__u8		tx_win;
>  	__u8		remote_tx_win;
>  	__u8		remote_max_tx;
>  	__u16		retrans_timeout;
> diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
> index 930f987..6679418 100644
> --- a/net/bluetooth/l2cap.c
> +++ b/net/bluetooth/l2cap.c
> @@ -780,6 +780,7 @@ static void l2cap_sock_init(struct sock *sk, struct
> sock *parent)
>  		pi->omtu = l2cap_pi(parent)->omtu;
>  		pi->mode = l2cap_pi(parent)->mode;
>  		pi->fcs  = l2cap_pi(parent)->fcs;
> +		pi->tx_win = l2cap_pi(parent)->tx_win;
>  		pi->sec_level = l2cap_pi(parent)->sec_level;
>  		pi->role_switch = l2cap_pi(parent)->role_switch;
>  		pi->force_reliable = l2cap_pi(parent)->force_reliable;
> @@ -788,6 +789,7 @@ static void l2cap_sock_init(struct sock *sk, struct
> sock *parent)
>  		pi->omtu = 0;
>  		pi->mode = L2CAP_MODE_BASIC;
>  		pi->fcs  = L2CAP_FCS_CRC16;
> +		pi->tx_win = L2CAP_DEFAULT_TX_WINDOW;
>  		pi->sec_level = BT_SECURITY_LOW;
>  		pi->role_switch = 0;
>  		pi->force_reliable = 0;
> @@ -1776,6 +1778,7 @@ static int l2cap_sock_setsockopt_old(struct
> socket *sock, int optname, char __us
>  		opts.flush_to = l2cap_pi(sk)->flush_to;
>  		opts.mode     = l2cap_pi(sk)->mode;
>  		opts.fcs      = l2cap_pi(sk)->fcs;
> +		opts.txwin_size = l2cap_pi(sk)->tx_win;
> 
>  		len = min_t(unsigned int, sizeof(opts), optlen);
>  		if (copy_from_user((char *) &opts, optval, len)) {
> @@ -1787,6 +1790,7 @@ static int l2cap_sock_setsockopt_old(struct
> socket *sock, int optname, char __us
>  		l2cap_pi(sk)->omtu = opts.omtu;
>  		l2cap_pi(sk)->mode = opts.mode;
>  		l2cap_pi(sk)->fcs  = opts.fcs;
> +		l2cap_pi(sk)->tx_win = opts.txwin_size;
>  		break;
> 
>  	case L2CAP_LM:
> @@ -1901,6 +1905,7 @@ static int l2cap_sock_getsockopt_old(struct
> socket *sock, int optname, char __us
>  		opts.flush_to = l2cap_pi(sk)->flush_to;
>  		opts.mode     = l2cap_pi(sk)->mode;
>  		opts.fcs      = l2cap_pi(sk)->fcs;
> +		opts.txwin_size = l2cap_pi(sk)->tx_win;
> 
>  		len = min_t(unsigned int, len, sizeof(opts));
>  		if (copy_to_user(optval, (char *) &opts, len))
> @@ -2318,7 +2323,7 @@ done:
> 
>  	case L2CAP_MODE_ERTM:
>  		rfc.mode            = L2CAP_MODE_ERTM;
> -		rfc.txwin_size      = L2CAP_DEFAULT_TX_WINDOW;
> +		rfc.txwin_size      = pi->tx_win;
>  		rfc.max_transmit    = max_transmit;
>  		rfc.retrans_timeout = 0;
>  		rfc.monitor_timeout = 0;


Mat Martineau
Qualcomm Innovation Center, Inc.,
A member of the Code Aurora Forum