Return-Path: Date: Fri, 19 Oct 2012 11:06:02 +0300 From: Andrei Emeltchenko To: Mat Martineau Cc: linux-bluetooth@vger.kernel.org, gustavo@padovan.org, sunnyk@codeaurora.org, marcel@holtmann.org Subject: Re: [PATCHv3 06/18] Bluetooth: Add new ERTM receive states for channel move Message-ID: <20121019080601.GE4249@aemeltch-MOBL1> References: <1350583130-3241-1-git-send-email-mathewm@codeaurora.org> <1350583130-3241-7-git-send-email-mathewm@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1350583130-3241-7-git-send-email-mathewm@codeaurora.org> List-ID: Hi Mat, On Thu, Oct 18, 2012 at 10:58:38AM -0700, Mat Martineau wrote: > Two new states are required to implement channel moves with the ERTM > receive state machine. > > The "WAIT_P" state is used by a move responder to wait for a "poll" > flag after a move is completed (success or failure). "WAIT_F" is > similarly used by a move initiator to wait for a "final" flag when the > move is completing. In either state, the reqseq value in the > poll/final frame tells the state machine exactly which frame should be > expected next. > > Signed-off-by: Mat Martineau > Acked-by: Marcel Holtmann Acked-by: Andrei Emeltchenko > --- > net/bluetooth/l2cap_core.c | 104 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 104 insertions(+) > > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c > index 42e20ee..ff25bf4 100644 > --- a/net/bluetooth/l2cap_core.c > +++ b/net/bluetooth/l2cap_core.c > @@ -4706,6 +4706,12 @@ static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, > return err; > } > > +static int l2cap_resegment(struct l2cap_chan *chan) > +{ > + /* Placeholder */ > + return 0; > +} > + > void l2cap_chan_busy(struct l2cap_chan *chan, int busy) > { > u8 event; > @@ -5211,6 +5217,98 @@ static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan, > return err; > } > > +static int l2cap_finish_move(struct l2cap_chan *chan) > +{ > + BT_DBG("chan %p", chan); > + > + chan->move_role = L2CAP_MOVE_ROLE_NONE; > + chan->rx_state = L2CAP_RX_STATE_RECV; > + > + if (chan->hs_hcon) > + chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; > + else > + chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; > + > + return l2cap_resegment(chan); > +} > + > +static int l2cap_rx_state_wait_p(struct l2cap_chan *chan, > + struct l2cap_ctrl *control, > + struct sk_buff *skb, u8 event) > +{ > + int err; > + > + BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb, > + event); > + > + if (!control->poll) > + return -EPROTO; > + > + l2cap_process_reqseq(chan, control->reqseq); > + > + if (!skb_queue_empty(&chan->tx_q)) > + chan->tx_send_head = skb_peek(&chan->tx_q); > + else > + chan->tx_send_head = NULL; > + > + /* Rewind next_tx_seq to the point expected > + * by the receiver. > + */ > + chan->next_tx_seq = control->reqseq; > + chan->unacked_frames = 0; > + > + err = l2cap_finish_move(chan); > + if (err) > + return err; > + > + set_bit(CONN_SEND_FBIT, &chan->conn_state); > + l2cap_send_i_or_rr_or_rnr(chan); > + > + if (event == L2CAP_EV_RECV_IFRAME) > + return -EPROTO; > + > + return l2cap_rx_state_recv(chan, control, NULL, event); > +} > + > +static int l2cap_rx_state_wait_f(struct l2cap_chan *chan, > + struct l2cap_ctrl *control, > + struct sk_buff *skb, u8 event) > +{ > + int err; > + > + if (!control->final) > + return -EPROTO; > + > + clear_bit(CONN_REMOTE_BUSY, &chan->conn_state); > + chan->move_role = L2CAP_MOVE_ROLE_NONE; > + > + chan->rx_state = L2CAP_RX_STATE_RECV; > + l2cap_process_reqseq(chan, control->reqseq); > + > + if (!skb_queue_empty(&chan->tx_q)) > + chan->tx_send_head = skb_peek(&chan->tx_q); > + else > + chan->tx_send_head = NULL; > + > + /* Rewind next_tx_seq to the point expected > + * by the receiver. > + */ > + chan->next_tx_seq = control->reqseq; > + chan->unacked_frames = 0; > + > + if (chan->hs_hcon) > + chan->conn->mtu = chan->hs_hcon->hdev->block_mtu; > + else > + chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu; > + > + err = l2cap_resegment(chan); > + > + if (!err) > + err = l2cap_rx_state_recv(chan, control, skb, event); > + > + return err; > +} > + > static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq) > { > /* Make sure reqseq is for a packet that has been sent but not acked */ > @@ -5237,6 +5335,12 @@ static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control, > err = l2cap_rx_state_srej_sent(chan, control, skb, > event); > break; > + case L2CAP_RX_STATE_WAIT_P: > + err = l2cap_rx_state_wait_p(chan, control, skb, event); > + break; > + case L2CAP_RX_STATE_WAIT_F: > + err = l2cap_rx_state_wait_f(chan, control, skb, event); > + break; > default: > /* shut it down */ > break; > -- > 1.7.12.3 > > -- > Mat Martineau > > Employee of Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation