Bluetooth: EWS: extended window size option support
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>
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 18a08c5..6e34312 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1898,6 +1898,22 @@
}
}
+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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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,
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 48ad8ba..836d12e 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -331,7 +331,7 @@
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 @@
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 @@
break;
}
- if (opts.txwin_size > L2CAP_DEFAULT_TX_WINDOW) {
+ if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
err = -EINVAL;
break;
}
@@ -533,7 +533,7 @@
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: