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/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 08ad40b..51998ff 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -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 @@
#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 @@
__u8 fcs;
- __u8 tx_win;
+ __u16 tx_win;
__u8 max_tx;
__u16 retrans_timeout;
__u16 monitor_timeout;
@@ -357,7 +359,7 @@
struct sk_buff *sdu;
struct sk_buff *sdu_last_frag;
- __u8 remote_tx_win;
+ __u16 remote_tx_win;
__u8 remote_max_tx;
__u16 remote_mps;
@@ -442,6 +444,7 @@
CONF_CONNECT_PEND,
CONF_NO_FCS_RECV,
CONF_STATE2_DEVICE,
+ CONF_EWS_RECV,
};
#define L2CAP_CONF_MAX_CONF_REQ 2
@@ -465,6 +468,7 @@
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))
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: