Re: [RFCv5 03/26] Bluetooth: A2MP: Create A2MP channel

[Gustavo Padovan <gustavo@padovan.org>]

Hi Andrei,

* Andrei Emeltchenko <Andrei.Emeltchenko.news@gmail.com> [2012-03-23 18:13:43 +0200]:

> From: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> 
> Create and initialize fixed A2MP channel
> 
> Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> ---
>  include/net/bluetooth/l2cap.h |    6 +++-
>  net/bluetooth/Makefile        |    3 +-
>  net/bluetooth/a2mp.c          |   63 +++++++++++++++++++++++++++++++++++++++++
>  net/bluetooth/l2cap_core.c    |    4 +-
>  4 files changed, 72 insertions(+), 4 deletions(-)
>  create mode 100644 net/bluetooth/a2mp.c
> 
> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> index 9287c24..0f0ef6c 100644
> --- a/include/net/bluetooth/l2cap.h
> +++ b/include/net/bluetooth/l2cap.h
> @@ -51,6 +51,8 @@
>  #define L2CAP_CONN_TIMEOUT		msecs_to_jiffies(40000)
>  #define L2CAP_INFO_TIMEOUT		msecs_to_jiffies(4000)
>  
> +#define L2CAP_A2MP_DEFAULT_MTU		670
> +
>  /* L2CAP socket address */
>  struct sockaddr_l2 {
>  	sa_family_t	l2_family;
> @@ -224,6 +226,7 @@ struct l2cap_conn_rsp {
>  /* channel indentifier */
>  #define L2CAP_CID_SIGNALING	0x0001
>  #define L2CAP_CID_CONN_LESS	0x0002
> +#define L2CAP_CID_A2MP		0x0003
>  #define L2CAP_CID_LE_DATA	0x0004
>  #define L2CAP_CID_LE_SIGNALING	0x0005
>  #define L2CAP_CID_SMP		0x0006
> @@ -867,7 +870,8 @@ int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
>  								u32 priority);
>  void l2cap_chan_busy(struct l2cap_chan *chan, int busy);
>  int l2cap_chan_check_security(struct l2cap_chan *chan);
> -
> +void l2cap_ertm_init(struct l2cap_chan *chan);
> +void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
>  void __l2cap_chan_set_err(struct l2cap_chan *chan, int err);
>  
>  #endif /* __L2CAP_H */
> diff --git a/net/bluetooth/Makefile b/net/bluetooth/Makefile
> index 2dc5a57..fa6d94a 100644
> --- a/net/bluetooth/Makefile
> +++ b/net/bluetooth/Makefile
> @@ -9,4 +9,5 @@ obj-$(CONFIG_BT_CMTP)	+= cmtp/
>  obj-$(CONFIG_BT_HIDP)	+= hidp/
>  
>  bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \
> -	hci_sock.o hci_sysfs.o l2cap_core.o l2cap_sock.o smp.o sco.o lib.o
> +	hci_sock.o hci_sysfs.o l2cap_core.o l2cap_sock.o smp.o sco.o lib.o \
> +	a2mp.o
> diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c
> new file mode 100644
> index 0000000..967e0f1
> --- /dev/null
> +++ b/net/bluetooth/a2mp.c
> @@ -0,0 +1,63 @@
> +/*
> +   Copyright (c) 2010,2011 Code Aurora Forum.  All rights reserved.
> +   Copyright (c) 2011,2012 Intel Corp.
> +
> +   This program is free software; you can redistribute it and/or modify
> +   it under the terms of the GNU General Public License version 2 and
> +   only version 2 as published by the Free Software Foundation.
> +
> +   This program is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +   GNU General Public License for more details.
> +*/
> +
> +#include <net/bluetooth/bluetooth.h>
> +#include <net/bluetooth/hci_core.h>
> +#include <net/bluetooth/l2cap.h>
> +
> +static struct l2cap_ops a2mp_chan_ops = {
> +	.name = "L2CAP A2MP channel",
> +};
> +
> +static struct l2cap_chan *open_a2mp_chan(struct l2cap_conn *conn)

a2mp_chan_open() is a better name here. Who is calling this btw?

> +{
> +	struct l2cap_chan *chan;
> +
> +	chan = l2cap_chan_create(NULL);

I just pushed a patch that remove the sk parameter from l2cap_chan_create(),
so you don't need to pass NULL here anymore.

You failing to check l2cap_chan_create() for NULL return btw.

> +
> +	hci_conn_hold(conn->hcon);
> +
> +	BT_DBG("chan %p", chan);
> +
> +	chan->sec_level = BT_SECURITY_LOW;
> +	chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
> +	chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
> +	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
> +	chan->fcs = L2CAP_FCS_CRC16;
> +
> +	chan->ops = &a2mp_chan_ops;
> +
> +	set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
> +
> +	chan->max_tx = L2CAP_DEFAULT_MAX_TX;
> +	chan->remote_max_tx = chan->max_tx;
> +
> +	chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
> +	chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
> +	chan->remote_tx_win = chan->tx_win;
> +
> +	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
> +	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
> +
> +	skb_queue_head_init(&chan->tx_q);

I think we should move all ERTM related settings here inside
l2cap_ertm_init(), it will make this code much more cleaner.

	Gustavo