Bluetooth: EWS: extended window size option support
authorAndrei Emeltchenko <andrei.emeltchenko@intel.com>
Tue, 11 Oct 2011 10:37:42 +0000 (13:37 +0300)
committerGustavo F. Padovan <padovan@profusion.mobi>
Thu, 13 Oct 2011 19:44:26 +0000 (16:44 -0300)
Adds support for extended window size (EWS) config option. We enable EWS
feature in L2CAP Info RSP when hs enabled. EWS option is included in L2CAP
Config Req if tx_win (which is set via socket) bigger then standard default
value (63) && hs enabled && remote side supports EWS feature.

Using EWS selects extended control field in L2CAP.

Code partly based on Qualcomm and Atheros patches sent upstream a year ago.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
include/net/bluetooth/l2cap.h
net/bluetooth/l2cap_core.c
net/bluetooth/l2cap_sock.c

index 08ad40b..51998ff 100644 (file)
@@ -32,6 +32,7 @@
 #define L2CAP_DEFAULT_MIN_MTU          48
 #define L2CAP_DEFAULT_FLUSH_TO         0xffff
 #define L2CAP_DEFAULT_TX_WINDOW                63
+#define L2CAP_DEFAULT_EXT_WINDOW       0x3FFF
 #define L2CAP_DEFAULT_MAX_TX           3
 #define L2CAP_DEFAULT_RETRANS_TO       2000    /* 2 seconds */
 #define L2CAP_DEFAULT_MONITOR_TO       12000   /* 12 seconds */
@@ -233,6 +234,7 @@ struct l2cap_conf_opt {
 #define L2CAP_CONF_QOS         0x03
 #define L2CAP_CONF_RFC         0x04
 #define L2CAP_CONF_FCS         0x05
+#define L2CAP_CONF_EWS         0x07
 
 #define L2CAP_CONF_MAX_SIZE    22
 
@@ -333,7 +335,7 @@ struct l2cap_chan {
 
        __u8            fcs;
 
-       __u           tx_win;
+       __u16           tx_win;
        __u8            max_tx;
        __u16           retrans_timeout;
        __u16           monitor_timeout;
@@ -357,7 +359,7 @@ struct l2cap_chan {
        struct sk_buff  *sdu;
        struct sk_buff  *sdu_last_frag;
 
-       __u           remote_tx_win;
+       __u16           remote_tx_win;
        __u8            remote_max_tx;
        __u16           remote_mps;
 
@@ -442,6 +444,7 @@ enum {
        CONF_CONNECT_PEND,
        CONF_NO_FCS_RECV,
        CONF_STATE2_DEVICE,
+       CONF_EWS_RECV,
 };
 
 #define L2CAP_CONF_MAX_CONF_REQ 2
@@ -465,6 +468,7 @@ enum {
        FLAG_FORCE_ACTIVE,
        FLAG_FORCE_RELIABLE,
        FLAG_FLUSHABLE,
+       FLAG_EXT_CTRL,
 };
 
 #define __set_chan_timer(c, t) l2cap_set_timer(c, &c->chan_timer, (t))
index 18a08c5..6e34312 100644 (file)
@@ -1898,6 +1898,22 @@ static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
        }
 }
 
+static inline bool __l2cap_ews_supported(struct l2cap_chan *chan)
+{
+       return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
+}
+
+static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
+{
+       if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
+                                               __l2cap_ews_supported(chan))
+               /* use extended control field */
+               set_bit(FLAG_EXT_CTRL, &chan->flags);
+       else
+               chan->tx_win = min_t(u16, chan->tx_win,
+                                               L2CAP_DEFAULT_TX_WINDOW);
+}
+
 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
 {
        struct l2cap_conf_req *req = data;
@@ -1944,7 +1960,6 @@ done:
 
        case L2CAP_MODE_ERTM:
                rfc.mode            = L2CAP_MODE_ERTM;
-               rfc.txwin_size      = chan->tx_win;
                rfc.max_transmit    = chan->max_tx;
                rfc.retrans_timeout = 0;
                rfc.monitor_timeout = 0;
@@ -1952,6 +1967,11 @@ done:
                if (L2CAP_DEFAULT_MAX_PDU_SIZE > chan->conn->mtu - 10)
                        rfc.max_pdu_size = cpu_to_le16(chan->conn->mtu - 10);
 
+               l2cap_txwin_setup(chan);
+
+               rfc.txwin_size = min_t(u16, chan->tx_win,
+                                               L2CAP_DEFAULT_TX_WINDOW);
+
                l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
                                                        (unsigned long) &rfc);
 
@@ -1963,6 +1983,10 @@ done:
                        chan->fcs = L2CAP_FCS_NONE;
                        l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, chan->fcs);
                }
+
+               if (test_bit(FLAG_EXT_CTRL, &chan->flags))
+                       l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
+                                                               chan->tx_win);
                break;
 
        case L2CAP_MODE_STREAMING:
@@ -2038,6 +2062,15 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
 
                        break;
 
+               case L2CAP_CONF_EWS:
+                       if (!enable_hs)
+                               return -ECONNREFUSED;
+
+                       set_bit(FLAG_EXT_CTRL, &chan->flags);
+                       set_bit(CONF_EWS_RECV, &chan->conf_state);
+                       chan->remote_tx_win = val;
+                       break;
+
                default:
                        if (hint)
                                break;
@@ -2098,7 +2131,11 @@ done:
                        break;
 
                case L2CAP_MODE_ERTM:
-                       chan->remote_tx_win = rfc.txwin_size;
+                       if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
+                               chan->remote_tx_win = rfc.txwin_size;
+                       else
+                               rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
+
                        chan->remote_max_tx = rfc.max_transmit;
 
                        if (le16_to_cpu(rfc.max_pdu_size) > chan->conn->mtu - 10)
@@ -2190,6 +2227,13 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, voi
                        l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
                                        sizeof(rfc), (unsigned long) &rfc);
                        break;
+
+               case L2CAP_CONF_EWS:
+                       chan->tx_win = min_t(u16, val,
+                                               L2CAP_DEFAULT_EXT_WINDOW);
+                       l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS,
+                                                       2, chan->tx_win);
+                       break;
                }
        }
 
@@ -2785,7 +2829,8 @@ static inline int l2cap_information_req(struct l2cap_conn *conn, struct l2cap_cm
                        feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
                                                         | L2CAP_FEAT_FCS;
                if (enable_hs)
-                       feat_mask |= L2CAP_FEAT_EXT_FLOW;
+                       feat_mask |= L2CAP_FEAT_EXT_FLOW
+                                               | L2CAP_FEAT_EXT_WINDOW;
 
                put_unaligned_le32(feat_mask, rsp->data);
                l2cap_send_cmd(conn, cmd->ident,
index 48ad8ba..836d12e 100644 (file)
@@ -331,7 +331,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __us
                opts.mode     = chan->mode;
                opts.fcs      = chan->fcs;
                opts.max_tx   = chan->max_tx;
-               opts.txwin_size = (__u16)chan->tx_win;
+               opts.txwin_size = chan->tx_win;
 
                len = min_t(unsigned int, len, sizeof(opts));
                if (copy_to_user(optval, (char *) &opts, len))
@@ -501,7 +501,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                opts.mode     = chan->mode;
                opts.fcs      = chan->fcs;
                opts.max_tx   = chan->max_tx;
-               opts.txwin_size = (__u16)chan->tx_win;
+               opts.txwin_size = chan->tx_win;
 
                len = min_t(unsigned int, sizeof(opts), optlen);
                if (copy_from_user((char *) &opts, optval, len)) {
@@ -509,7 +509,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                        break;
                }
 
-               if (opts.txwin_size > L2CAP_DEFAULT_TX_WINDOW) {
+               if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
                        err = -EINVAL;
                        break;
                }
@@ -533,7 +533,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                chan->omtu = opts.omtu;
                chan->fcs  = opts.fcs;
                chan->max_tx = opts.max_tx;
-               chan->tx_win = (__u8)opts.txwin_size;
+               chan->tx_win = opts.txwin_size;
                break;
 
        case L2CAP_LM: