Bluetooth: EWS: support extended seq numbers

Adds support for extended sequence numbers found in
extended control fields.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index e727555..fb1acb3 100644 (file)
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -158,7 +158,7 @@ struct bt_skb_cb {
        __u8 pkt_type;
        __u8 incoming;
        __u16 expect;
-       __u8 tx_seq;
+       __u16 tx_seq;
        __u8 retries;
        __u8 sar;
        unsigned short channel;

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 41f0906..fddc82a 100644 (file)
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -381,6 +381,7 @@ struct l2cap_chan {
        __u8            fcs;
 
        __u16           tx_win;
+       __u16           tx_win_max;
        __u8            max_tx;
        __u16           retrans_timeout;
        __u16           monitor_timeout;
@@ -543,6 +544,22 @@ enum {
                L2CAP_DEFAULT_ACK_TO);
 #define __clear_ack_timer(c) l2cap_clear_timer(c, &c->ack_timer)
 
+static inline int __seq_offset(struct l2cap_chan *chan, __u16 seq1, __u16 seq2)
+{
+       int offset;
+
+       offset = (seq1 - seq2) % (chan->tx_win_max + 1);
+       if (offset < 0)
+               offset += (chan->tx_win_max + 1);
+
+       return offset;
+}
+
+static inline __u16 __next_seq(struct l2cap_chan *chan, __u16 seq)
+{
+       return (seq + 1) % (chan->tx_win_max + 1);
+}
+
 static inline int l2cap_tx_window_full(struct l2cap_chan *ch)
 {
        int sub;

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index a253942..86c8720 100644 (file)
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1295,7 +1295,7 @@ static void l2cap_streaming_send(struct l2cap_chan *chan)
 
                l2cap_do_send(chan, skb);
 
-               chan->next_tx_seq = (chan->next_tx_seq + 1) % 64;
+               chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
        }
 }
 
@@ -1389,7 +1389,8 @@ static int l2cap_ertm_send(struct l2cap_chan *chan)
                __set_retrans_timer(chan);
 
                bt_cb(skb)->tx_seq = chan->next_tx_seq;
-               chan->next_tx_seq = (chan->next_tx_seq + 1) % 64;
+
+               chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
 
                if (bt_cb(skb)->retries == 1)
                        chan->unacked_frames++;
@@ -1967,12 +1968,15 @@ static inline bool __l2cap_efs_supported(struct l2cap_chan *chan)
 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
 {
        if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
-                                               __l2cap_ews_supported(chan))
+                                               __l2cap_ews_supported(chan)) {
                /* use extended control field */
                set_bit(FLAG_EXT_CTRL, &chan->flags);
-       else
+               chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
+       } else {
                chan->tx_win = min_t(u16, chan->tx_win,
                                                L2CAP_DEFAULT_TX_WINDOW);
+               chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
+       }
 }
 
 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
@@ -2138,6 +2142,7 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
 
                        set_bit(FLAG_EXT_CTRL, &chan->flags);
                        set_bit(CONF_EWS_RECV, &chan->conf_state);
+                       chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
                        chan->remote_tx_win = val;
                        break;
 
@@ -3225,18 +3230,14 @@ static int l2cap_add_to_srej_queue(struct l2cap_chan *chan, struct sk_buff *skb,
                return 0;
        }
 
-       tx_seq_offset = (tx_seq - chan->buffer_seq) % 64;
-       if (tx_seq_offset < 0)
-               tx_seq_offset += 64;
+       tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
 
        do {
                if (bt_cb(next_skb)->tx_seq == tx_seq)
                        return -EINVAL;
 
-               next_tx_seq_offset = (bt_cb(next_skb)->tx_seq -
-                                               chan->buffer_seq) % 64;
-               if (next_tx_seq_offset < 0)
-                       next_tx_seq_offset += 64;
+               next_tx_seq_offset = __seq_offset(chan,
+                               bt_cb(next_skb)->tx_seq, chan->buffer_seq);
 
                if (next_tx_seq_offset > tx_seq_offset) {
                        __skb_queue_before(&chan->srej_q, next_skb, skb);
@@ -3426,9 +3427,8 @@ static void l2cap_check_srej_gap(struct l2cap_chan *chan, u16 tx_seq)
                        break;
                }
 
-               chan->buffer_seq_srej =
-                       (chan->buffer_seq_srej + 1) % 64;
-               tx_seq = (tx_seq + 1) % 64;
+               chan->buffer_seq_srej = __next_seq(chan, chan->buffer_seq_srej);
+               tx_seq = __next_seq(chan, tx_seq);
        }
 }
 
@@ -3463,10 +3463,13 @@ static void l2cap_send_srejframe(struct l2cap_chan *chan, u16 tx_seq)
 
                new = kzalloc(sizeof(struct srej_list), GFP_ATOMIC);
                new->tx_seq = chan->expected_tx_seq;
-               chan->expected_tx_seq = (chan->expected_tx_seq + 1) % 64;
+
+               chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
+
                list_add_tail(&new->list, &chan->srej_l);
        }
-       chan->expected_tx_seq = (chan->expected_tx_seq + 1) % 64;
+
+       chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
 }
 
 static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_control, struct sk_buff *skb)
@@ -3492,9 +3495,7 @@ static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_cont
        chan->expected_ack_seq = req_seq;
        l2cap_drop_acked_frames(chan);
 
-       tx_seq_offset = (tx_seq - chan->buffer_seq) % 64;
-       if (tx_seq_offset < 0)
-               tx_seq_offset += 64;
+       tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
 
        /* invalid tx_seq */
        if (tx_seq_offset >= chan->tx_win) {
@@ -3542,10 +3543,8 @@ static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_cont
                        l2cap_send_srejframe(chan, tx_seq);
                }
        } else {
-               expected_tx_seq_offset =
-                       (chan->expected_tx_seq - chan->buffer_seq) % 64;
-               if (expected_tx_seq_offset < 0)
-                       expected_tx_seq_offset += 64;
+               expected_tx_seq_offset = __seq_offset(chan,
+                               chan->expected_tx_seq, chan->buffer_seq);
 
                /* duplicated tx_seq */
                if (tx_seq_offset < expected_tx_seq_offset)
@@ -3570,7 +3569,7 @@ static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_cont
        return 0;
 
 expected:
-       chan->expected_tx_seq = (chan->expected_tx_seq + 1) % 64;
+       chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
 
        if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
                bt_cb(skb)->tx_seq = tx_seq;
@@ -3580,7 +3579,8 @@ expected:
        }
 
        err = l2cap_reassemble_sdu(chan, skb, rx_control);
-       chan->buffer_seq = (chan->buffer_seq + 1) % 64;
+       chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
+
        if (err < 0) {
                l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
                return err;
@@ -3794,14 +3794,11 @@ static int l2cap_ertm_data_rcv(struct sock *sk, struct sk_buff *skb)
        }
 
        req_seq = __get_reqseq(chan, control);
-       req_seq_offset = (req_seq - chan->expected_ack_seq) % 64;
-       if (req_seq_offset < 0)
-               req_seq_offset += 64;
 
-       next_tx_seq_offset =
-               (chan->next_tx_seq - chan->expected_ack_seq) % 64;
-       if (next_tx_seq_offset < 0)
-               next_tx_seq_offset += 64;
+       req_seq_offset = __seq_offset(chan, req_seq, chan->expected_ack_seq);
+
+       next_tx_seq_offset = __seq_offset(chan, chan->next_tx_seq,
+                                               chan->expected_ack_seq);
 
        /* check for invalid req-seq */
        if (req_seq_offset > next_tx_seq_offset) {
@@ -3907,7 +3904,7 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                        /* TODO: Notify userland of missing data */
                }
 
-               chan->expected_tx_seq = (tx_seq + 1) % 64;
+               chan->expected_tx_seq = __next_seq(chan, tx_seq);
 
                if (l2cap_reassemble_sdu(chan, skb, control) == -EMSGSIZE)
                        l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);