From f80842a83ec224e70ebbd11a20832e71e5911b45 Mon Sep 17 00:00:00 2001 From: Mat Martineau Date: Thu, 17 May 2012 20:53:46 -0700 Subject: [PATCH] Bluetooth: Handle SREJ requests to resend unacked frames When a remote device sends an SREJ, retransmit the frame with the corresponding sequence number (subject to special cases with poll and final flags). An SREJ is also an implicit indication the the remote device is not in a busy state. Signed-off-by: Mat Martineau Signed-off-by: Gustavo Padovan --- net/bluetooth/l2cap_core.c | 70 +++++++++++++++++++++++++++++++++++++- 1 file changed, 69 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index fd324d4cb217..36842a29bb47 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1836,6 +1836,15 @@ static void l2cap_ertm_resend(struct l2cap_chan *chan) } } +static void l2cap_retransmit(struct l2cap_chan *chan, + struct l2cap_ctrl *control) +{ + BT_DBG("chan %p, control %p", chan, control); + + l2cap_seq_list_append(&chan->retrans_list, control->reqseq); + l2cap_ertm_resend(chan); +} + static void l2cap_retransmit_all(struct l2cap_chan *chan, struct l2cap_ctrl *control) { @@ -2532,6 +2541,13 @@ static void l2cap_pass_to_tx(struct l2cap_chan *chan, l2cap_tx(chan, control, 0, L2CAP_EV_RECV_REQSEQ_AND_FBIT); } +static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan, + struct l2cap_ctrl *control) +{ + BT_DBG("chan %p, control %p", chan, control); + l2cap_tx(chan, control, 0, L2CAP_EV_RECV_FBIT); +} + /* Copy frame to all raw sockets on that connection */ static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb) { @@ -4539,7 +4555,59 @@ static int l2cap_rx_queued_iframes(struct l2cap_chan *chan) static void l2cap_handle_srej(struct l2cap_chan *chan, struct l2cap_ctrl *control) { - /* Placeholder */ + struct sk_buff *skb; + + BT_DBG("chan %p, control %p", chan, control); + + if (control->reqseq == chan->next_tx_seq) { + BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq); + l2cap_send_disconn_req(chan->conn, chan, ECONNRESET); + return; + } + + skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq); + + if (skb == NULL) { + BT_DBG("Seq %d not available for retransmission", + control->reqseq); + return; + } + + if (chan->max_tx != 0 && bt_cb(skb)->control.retries >= chan->max_tx) { + BT_DBG("Retry limit exceeded (%d)", chan->max_tx); + l2cap_send_disconn_req(chan->conn, chan, ECONNRESET); + return; + } + + clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); + + if (control->poll) { + l2cap_pass_to_tx(chan, control); + + set_bit(CONN_SEND_FBIT, &chan->conn_state); + l2cap_retransmit(chan, control); + l2cap_ertm_send(chan); + + if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { + set_bit(CONN_SREJ_ACT, &chan->conn_state); + chan->srej_save_reqseq = control->reqseq; + } + } else { + l2cap_pass_to_tx_fbit(chan, control); + + if (control->final) { + if (chan->srej_save_reqseq != control->reqseq || + !test_and_clear_bit(CONN_SREJ_ACT, + &chan->conn_state)) + l2cap_retransmit(chan, control); + } else { + l2cap_retransmit(chan, control); + if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) { + set_bit(CONN_SREJ_ACT, &chan->conn_state); + chan->srej_save_reqseq = control->reqseq; + } + } + } } static void l2cap_handle_rej(struct l2cap_chan *chan, -- 2.20.1