Return-Path: Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.2 \(1874\)) Subject: Re: [PATCH 3/3] Bluetooth: 6LoWPAN: Use connected oriented channel instead of fixed one From: Marcel Holtmann In-Reply-To: <1399282285-32743-4-git-send-email-jukka.rissanen@linux.intel.com> Date: Mon, 5 May 2014 19:11:34 -0700 Cc: linux-bluetooth@vger.kernel.org Message-Id: <0319CACA-1EEC-4928-9C06-688937728B21@holtmann.org> References: <1399282285-32743-1-git-send-email-jukka.rissanen@linux.intel.com> <1399282285-32743-4-git-send-email-jukka.rissanen@linux.intel.com> To: Jukka Rissanen Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Jukka, > Create a CoC dynamically instead of one fixed channel for communication > to peer devices. > > Signed-off-by: Jukka Rissanen > --- > include/net/bluetooth/l2cap.h | 3 +- > net/bluetooth/6lowpan.c | 470 ++++++++++++++++++++++++++---------------- > net/bluetooth/6lowpan.h | 19 +- > net/bluetooth/l2cap_core.c | 19 +- > 4 files changed, 308 insertions(+), 203 deletions(-) > > diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h > index 4abdcb2..ddf0b35 100644 > --- a/include/net/bluetooth/l2cap.h > +++ b/include/net/bluetooth/l2cap.h > @@ -137,7 +137,6 @@ struct l2cap_conninfo { > #define L2CAP_FC_L2CAP 0x02 > #define L2CAP_FC_CONNLESS 0x04 > #define L2CAP_FC_A2MP 0x08 > -#define L2CAP_FC_6LOWPAN 0x3e /* reserved and temporary value */ > > /* L2CAP Control Field bit masks */ > #define L2CAP_CTRL_SAR 0xC000 > @@ -244,6 +243,7 @@ struct l2cap_conn_rsp { > #define L2CAP_PSM_SDP 0x0001 > #define L2CAP_PSM_RFCOMM 0x0003 > #define L2CAP_PSM_3DSP 0x0021 > +#define L2CAP_PSM_6LOWPAN 0x003e since we have no officially assigned value, please mark this one as temporary as well. It might be actually a good idea to allow providing this value via debugfs. > > /* channel identifier */ > #define L2CAP_CID_SIGNALING 0x0001 > @@ -626,6 +626,7 @@ struct l2cap_conn { > > struct sk_buff_head pending_rx; > struct work_struct pending_rx_work; > + struct work_struct pending_6lowpan_work; Please start thinking on how we can reach the level that bluetooth_6lowpan.ko can be its own module. So all 6loWPAN specific pieces should be externally to l2cap_conn. > > __u8 disc_reason; > > diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c > index adb3ea0..f885836 100644 > --- a/net/bluetooth/6lowpan.c > +++ b/net/bluetooth/6lowpan.c > @@ -1,5 +1,5 @@ > /* > - Copyright (c) 2013 Intel Corp. > + Copyright (c) 2014 Intel Corp. Make it 2013-2014. the 2013 copyright is not magically going away ;) > > This program is free software; you can redistribute it and/or modify > it under the terms of the GNU General Public License version 2 and > @@ -29,12 +29,14 @@ > > #include "../ieee802154/6lowpan.h" /* for the compression support */ > > +static struct l2cap_chan *chan_create(struct l2cap_conn *conn); > + > #define IFACE_NAME_TEMPLATE "bt%d" > #define EUI64_ADDR_LEN 8 > > struct skb_cb { > struct in6_addr addr; > - struct l2cap_conn *conn; > + struct l2cap_chan *chan; > }; > #define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb)) > > @@ -50,7 +52,7 @@ static DEFINE_RWLOCK(devices_lock); > > struct lowpan_peer { > struct list_head list; > - struct l2cap_conn *conn; > + struct l2cap_chan *chan; > > /* peer addresses in various formats */ > unsigned char eui64_addr[EUI64_ADDR_LEN]; > @@ -102,12 +104,26 @@ static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_dev *dev, > > list_for_each_entry_safe(peer, tmp, &dev->peers, list) { > BT_DBG("addr %pMR type %d", > - &peer->conn->hcon->dst, peer->conn->hcon->dst_type); > + &peer->chan->conn->hcon->dst, > + peer->chan->conn->hcon->dst_type); > > - if (bacmp(&peer->conn->hcon->dst, ba)) > + if (bacmp(&peer->chan->conn->hcon->dst, ba)) > continue; > > - if (type == peer->conn->hcon->dst_type) > + if (type == peer->chan->conn->hcon->dst_type) > + return peer; > + } I wonder if we need simple accessor helpers for BD_ADDR and BD_ADDR type. The dereference chain looks scary. > + > + return NULL; > +} > + > +static inline struct lowpan_peer *peer_lookup_chan(struct lowpan_dev *dev, > + struct l2cap_chan *chan) > +{ > + struct lowpan_peer *peer, *tmp; > + > + list_for_each_entry_safe(peer, tmp, &dev->peers, list) { > + if (peer->chan == chan) > return peer; > } > > @@ -120,7 +136,7 @@ static inline struct lowpan_peer *peer_lookup_conn(struct lowpan_dev *dev, > struct lowpan_peer *peer, *tmp; > > list_for_each_entry_safe(peer, tmp, &dev->peers, list) { > - if (peer->conn == conn) > + if (peer->chan->conn == conn) > return peer; > } > > @@ -185,7 +201,7 @@ static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev) > } > > static int process_data(struct sk_buff *skb, struct net_device *netdev, > - struct l2cap_conn *conn) > + struct l2cap_chan *chan) > { > const u8 *saddr, *daddr; > u8 iphc0, iphc1; > @@ -196,7 +212,7 @@ static int process_data(struct sk_buff *skb, struct net_device *netdev, > dev = lowpan_dev(netdev); > > read_lock_irqsave(&devices_lock, flags); > - peer = peer_lookup_conn(dev, conn); > + peer = peer_lookup_chan(dev, chan); > read_unlock_irqrestore(&devices_lock, flags); > if (!peer) > goto drop; > @@ -225,7 +241,7 @@ drop: > } > > static int recv_pkt(struct sk_buff *skb, struct net_device *dev, > - struct l2cap_conn *conn) > + struct l2cap_chan *chan) > { > struct sk_buff *local_skb; > int ret; > @@ -269,7 +285,7 @@ static int recv_pkt(struct sk_buff *skb, struct net_device *dev, > if (!local_skb) > goto drop; > > - ret = process_data(local_skb, dev, conn); > + ret = process_data(local_skb, dev, chan); > if (ret != NET_RX_SUCCESS) > goto drop; > > @@ -291,135 +307,27 @@ drop: > } > > /* Packet from BT LE device */ > -int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb) > +static int bt_6lowpan_chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) > { > struct lowpan_dev *dev; > struct lowpan_peer *peer; > int err; > > - peer = lookup_peer(conn); > + peer = lookup_peer(chan->conn); > if (!peer) > return -ENOENT; > > - dev = lookup_dev(conn); > + dev = lookup_dev(chan->conn); > if (!dev || !dev->netdev) > return -ENOENT; > > - err = recv_pkt(skb, dev->netdev, conn); > + err = recv_pkt(skb, dev->netdev, chan); > + > BT_DBG("recv pkt %d", err); > > return err; > } > > -static inline int skbuff_copy(void *msg, int len, int count, int mtu, > - struct sk_buff *skb, struct net_device *dev) > -{ > - struct sk_buff **frag; > - int sent = 0; > - > - memcpy(skb_put(skb, count), msg, count); > - > - sent += count; > - msg += count; > - len -= count; > - > - dev->stats.tx_bytes += count; > - dev->stats.tx_packets++; > - > - raw_dump_table(__func__, "Sending", skb->data, skb->len); > - > - /* Continuation fragments (no L2CAP header) */ > - frag = &skb_shinfo(skb)->frag_list; > - while (len > 0) { > - struct sk_buff *tmp; > - > - count = min_t(unsigned int, mtu, len); > - > - tmp = bt_skb_alloc(count, GFP_ATOMIC); > - if (!tmp) > - return -ENOMEM; > - > - *frag = tmp; > - > - memcpy(skb_put(*frag, count), msg, count); > - > - raw_dump_table(__func__, "Sending fragment", > - (*frag)->data, count); > - > - (*frag)->priority = skb->priority; > - > - sent += count; > - msg += count; > - len -= count; > - > - skb->len += (*frag)->len; > - skb->data_len += (*frag)->len; > - > - frag = &(*frag)->next; > - > - dev->stats.tx_bytes += count; > - dev->stats.tx_packets++; > - } > - > - return sent; > -} > - > -static struct sk_buff *create_pdu(struct l2cap_conn *conn, void *msg, > - size_t len, u32 priority, > - struct net_device *dev) > -{ > - struct sk_buff *skb; > - int err, count; > - struct l2cap_hdr *lh; > - > - /* FIXME: This mtu check should be not needed and atm is only used for > - * testing purposes > - */ > - if (conn->mtu > (L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE)) > - conn->mtu = L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE; > - > - count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len); > - > - BT_DBG("conn %p len %zu mtu %d count %d", conn, len, conn->mtu, count); > - > - skb = bt_skb_alloc(count + L2CAP_HDR_SIZE, GFP_ATOMIC); > - if (!skb) > - return ERR_PTR(-ENOMEM); > - > - skb->priority = priority; > - > - lh = (struct l2cap_hdr *)skb_put(skb, L2CAP_HDR_SIZE); > - lh->cid = cpu_to_le16(L2CAP_FC_6LOWPAN); > - lh->len = cpu_to_le16(len); > - > - err = skbuff_copy(msg, len, count, conn->mtu, skb, dev); > - if (unlikely(err < 0)) { > - kfree_skb(skb); > - BT_DBG("skbuff copy %d failed", err); > - return ERR_PTR(err); > - } > - > - return skb; > -} > - > -static int conn_send(struct l2cap_conn *conn, > - void *msg, size_t len, u32 priority, > - struct net_device *dev) > -{ > - struct sk_buff *skb; > - > - skb = create_pdu(conn, msg, len, priority, dev); > - if (IS_ERR(skb)) > - return -EINVAL; > - > - BT_DBG("conn %p skb %p len %d priority %u", conn, skb, skb->len, > - skb->priority); > - > - hci_send_acl(conn->hchan, skb, ACL_START); > - > - return 0; > -} > - > static void get_dest_bdaddr(struct in6_addr *ip6_daddr, > bdaddr_t *addr, u8 *addr_type) > { > @@ -466,7 +374,7 @@ static int header_create(struct sk_buff *skb, struct net_device *netdev, > if (ipv6_addr_is_multicast(&hdr->daddr)) { > memcpy(&lowpan_cb(skb)->addr, &hdr->daddr, > sizeof(struct in6_addr)); > - lowpan_cb(skb)->conn = NULL; > + lowpan_cb(skb)->chan = NULL; > } else { > unsigned long flags; > > @@ -490,7 +398,7 @@ static int header_create(struct sk_buff *skb, struct net_device *netdev, > > memcpy(&lowpan_cb(skb)->addr, &hdr->daddr, > sizeof(struct in6_addr)); > - lowpan_cb(skb)->conn = peer->conn; > + lowpan_cb(skb)->chan = peer->chan; > } > > saddr = dev->netdev->dev_addr; > @@ -499,14 +407,32 @@ static int header_create(struct sk_buff *skb, struct net_device *netdev, > } > > /* Packet to BT LE device */ > -static int send_pkt(struct l2cap_conn *conn, const void *saddr, > +static int send_pkt(struct l2cap_chan *chan, const void *saddr, > const void *daddr, struct sk_buff *skb, > struct net_device *netdev) > { > - raw_dump_table(__func__, "raw skb data dump before fragmentation", > - skb->data, skb->len); > + struct kvec iv; > + struct msghdr msg; > + int err; > + > + iv.iov_base = skb->data; > + iv.iov_len = skb->len; > + > + memset(&msg, 0, sizeof(msg)); > + > + msg.msg_iov = (struct iovec *) &iv; > + msg.msg_iovlen = 1; > + > + chan->data = skb->sk; This assignment here is scary. Why? > + > + err = l2cap_chan_send(chan, &msg, skb->len, 0); so this here pretty much proofs my point. I think l2cap_chan_send needs to change to take a single buffer only. Single vector IOV are pretty much useless. We just push it into a single vector for no apparent reason. Lets just hand over the SKB itself to L2CAP core. Then we even have proper reference counting there. > + if (err > 0) { > + netdev->stats.tx_bytes += err; > + netdev->stats.tx_packets++; > + err = 0; > + } > > - return conn_send(conn, skb->data, skb->len, 0, netdev); > + return err; > } > > static void send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev) > @@ -529,7 +455,7 @@ static void send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev) > list_for_each_entry_safe(pentry, ptmp, &dev->peers, list) { > local_skb = skb_clone(skb, GFP_ATOMIC); > > - send_pkt(pentry->conn, netdev->dev_addr, > + send_pkt(pentry->chan, netdev->dev_addr, > pentry->eui64_addr, local_skb, netdev); > > kfree_skb(local_skb); > @@ -567,8 +493,8 @@ static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev) > BT_DBG("xmit from %s to %pMR (%pI6c) peer %p", netdev->name, > &addr, &lowpan_cb(skb)->addr, peer); > > - if (peer && peer->conn) > - err = send_pkt(peer->conn, netdev->dev_addr, > + if (peer && peer->chan) > + err = send_pkt(peer->chan, netdev->dev_addr, > eui64_addr, skb, netdev); > } > dev_kfree_skb(skb); > @@ -664,23 +590,40 @@ static bool is_bt_6lowpan(struct hci_conn *hcon) > return test_bit(HCI_CONN_6LOWPAN, &hcon->flags); > } > > -static int add_peer_conn(struct l2cap_conn *conn, struct lowpan_dev *dev) > +static struct l2cap_chan *chan_open(struct l2cap_chan *pchan) > +{ > + struct l2cap_chan *chan; > + > + chan = chan_create(pchan->conn); > + if (!chan) > + return NULL; > + > + chan->remote_mps = chan->omtu; > + chan->mps = chan->omtu; > + > + chan->state = BT_CONNECTED; > + > + return chan; > +} > + > +static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan, > + struct lowpan_dev *dev) > { > struct lowpan_peer *peer; > unsigned long flags; > > peer = kzalloc(sizeof(*peer), GFP_ATOMIC); > if (!peer) > - return -ENOMEM; > + return NULL; > > - peer->conn = conn; > + peer->chan = chan; > memset(&peer->peer_addr, 0, sizeof(struct in6_addr)); > > /* RFC 2464 ch. 5 */ > peer->peer_addr.s6_addr[0] = 0xFE; > peer->peer_addr.s6_addr[1] = 0x80; > - set_addr((u8 *)&peer->peer_addr.s6_addr + 8, conn->hcon->dst.b, > - conn->hcon->dst_type); > + set_addr((u8 *)&peer->peer_addr.s6_addr + 8, chan->conn->hcon->dst.b, > + chan->conn->hcon->dst_type); > > memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8, > EUI64_ADDR_LEN); > @@ -701,33 +644,17 @@ static int add_peer_conn(struct l2cap_conn *conn, struct lowpan_dev *dev) > INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers); > schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100)); > > - return 0; > + return peer->chan; > } > > -/* This gets called when BT LE 6LoWPAN device is connected. We then > - * create network device that acts as a proxy between BT LE device > - * and kernel network stack. > - */ > -int bt_6lowpan_add_conn(struct l2cap_conn *conn) > +static int setup_netdev(struct l2cap_conn *conn, struct lowpan_dev **dev) > { > - struct lowpan_peer *peer = NULL; > - struct lowpan_dev *dev; > struct net_device *netdev; > int err = 0; > unsigned long flags; > > - if (!is_bt_6lowpan(conn->hcon)) > - return 0; > - > - peer = lookup_peer(conn); > - if (peer) > - return -EEXIST; > - > - dev = lookup_dev(conn); > - if (dev) > - return add_peer_conn(conn, dev); > - > - netdev = alloc_netdev(sizeof(*dev), IFACE_NAME_TEMPLATE, netdev_setup); > + netdev = alloc_netdev(sizeof(struct lowpan_dev), IFACE_NAME_TEMPLATE, > + netdev_setup); > if (!netdev) > return -ENOMEM; > > @@ -748,24 +675,49 @@ int bt_6lowpan_add_conn(struct l2cap_conn *conn) > netdev->ifindex, &conn->hcon->dst, &conn->hcon->src); > set_bit(__LINK_STATE_PRESENT, &netdev->state); > > - dev = netdev_priv(netdev); > - dev->netdev = netdev; > - dev->hdev = conn->hcon->hdev; > - INIT_LIST_HEAD(&dev->peers); > + *dev = netdev_priv(netdev); > + (*dev)->netdev = netdev; > + (*dev)->hdev = conn->hcon->hdev; > + INIT_LIST_HEAD(&(*dev)->peers); > > write_lock_irqsave(&devices_lock, flags); > - INIT_LIST_HEAD(&dev->list); > - list_add(&dev->list, &bt_6lowpan_devices); > + INIT_LIST_HEAD(&(*dev)->list); > + list_add(&(*dev)->list, &bt_6lowpan_devices); > write_unlock_irqrestore(&devices_lock, flags); > > - ifup(netdev); > - > - return add_peer_conn(conn, dev); > + return 0; > > out: > return err; > } > > +static inline void bt_6lowpan_chan_ready_cb(struct l2cap_chan *chan) > +{ > + struct lowpan_dev *dev; > + > + dev = lookup_dev(chan->conn); > + > + BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev); > + > + if (!dev) { > + if (setup_netdev(chan->conn, &dev) < 0) { > + l2cap_chan_del(chan, -ENOENT); > + return; > + } > + } > + > + add_peer_chan(chan, dev); > + ifup(dev->netdev); > +} > + > +static inline > +struct l2cap_chan *bt_6lowpan_chan_new_connection_cb(struct l2cap_chan *chan) > +{ > + BT_DBG("chan %p", chan); > + > + return chan_open(chan); > +} > + > static void delete_netdev(struct work_struct *work) > { > struct lowpan_dev *entry = container_of(work, struct lowpan_dev, > @@ -776,26 +728,38 @@ static void delete_netdev(struct work_struct *work) > /* The entry pointer is deleted in device_event() */ > } > > -int bt_6lowpan_del_conn(struct l2cap_conn *conn) > +static void bt_6lowpan_chan_close_cb(struct l2cap_chan *chan) > { > struct lowpan_dev *entry, *tmp; > struct lowpan_dev *dev = NULL; > struct lowpan_peer *peer; > int err = -ENOENT; > unsigned long flags; > - bool last = false; > + bool last = false, removed = true; > + > + BT_DBG("chan %p conn %p", chan, chan->conn); > + > + if (chan->conn && chan->conn->hcon) { > + if (!is_bt_6lowpan(chan->conn->hcon)) > + return; > > - if (!conn || !is_bt_6lowpan(conn->hcon)) > - return 0; > + /* > + * If conn is set, then the netdev is also there and we should > + * remove it. > + */ > + removed = false; > + } > > write_lock_irqsave(&devices_lock, flags); > > list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) { > dev = lowpan_dev(entry->netdev); > - peer = peer_lookup_conn(dev, conn); > + peer = peer_lookup_chan(dev, chan); > if (peer) { > last = peer_del(dev, peer); > err = 0; > + BT_DBG("dev %p removing %speer %p", dev, > + last ? "last " : "1 ", peer); > break; > } > } > @@ -805,16 +769,166 @@ int bt_6lowpan_del_conn(struct l2cap_conn *conn) > > cancel_delayed_work_sync(&dev->notify_peers); > > - /* bt_6lowpan_del_conn() is called with hci dev lock held which > - * means that we must delete the netdevice in worker thread. > - */ > - INIT_WORK(&entry->delete_netdev, delete_netdev); > - schedule_work(&entry->delete_netdev); > + if (!removed) { > + INIT_WORK(&entry->delete_netdev, delete_netdev); > + schedule_work(&entry->delete_netdev); > + } > } else { > write_unlock_irqrestore(&devices_lock, flags); > } > > - return err; > + return; > +} > + > +static void bt_6lowpan_chan_state_change_cb(struct l2cap_chan *chan, int state, > + int err) > +{ > + BT_DBG("chan %p conn %p", chan, chan->conn); > +} > + > +static struct sk_buff *bt_6lowpan_chan_alloc_skb_cb(struct l2cap_chan *chan, > + unsigned long len, int nb) > +{ > + return bt_skb_alloc(len, GFP_ATOMIC); > +} > + > +static void bt_6lowpan_chan_suspend_cb(struct l2cap_chan *chan) > +{ > + struct sock *sk = chan->data; > + > + BT_DBG("chan %p conn %p sk %p", chan, chan->conn, sk); > + > + if (!sk) > + return; > + > + set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags); > + sk->sk_state_change(sk); > +} > + > +static void bt_6lowpan_chan_resume_cb(struct l2cap_chan *chan) > +{ > + struct sock *sk = chan->data; > + > + BT_DBG("chan %p conn %p sk %p", chan, chan->conn, sk); > + > + if (!sk) > + return; > + > + clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags); > + sk->sk_state_change(sk); > +} Why are you messing with socket states here for suspend/resume. These should be internal states to 6loWPAN since it is essentially there to stall IPv6 packets. Involving the socket makes no sense here. You do now have a socket in the first place. Where is this socket coming from? > + > +static long bt_l2cap_chan_get_sndtimeo(struct l2cap_chan *chan) > +{ > + return msecs_to_jiffies(1000); > +} Why is this needed. You do not have a socket? Do we have this specific timeout handling with LE L2CAP connection oriented channels? We should default to proper defaults or errors if this is not needed. > + > +static struct l2cap_ops bt_6lowpan_chan_ops = { > + .name = "L2CAP 6LoWPAN channel", > + .recv = bt_6lowpan_chan_recv_cb, > + .close = bt_6lowpan_chan_close_cb, > + .state_change = bt_6lowpan_chan_state_change_cb, > + .alloc_skb = bt_6lowpan_chan_alloc_skb_cb, > + .new_connection = bt_6lowpan_chan_new_connection_cb, > + .suspend = bt_6lowpan_chan_suspend_cb, > + .resume = bt_6lowpan_chan_resume_cb, > + .ready = bt_6lowpan_chan_ready_cb, > + .get_sndtimeo = bt_l2cap_chan_get_sndtimeo, > + > + /* Not implemented for 6LoWPAN */ > + .defer = l2cap_chan_no_defer, > + .teardown = l2cap_chan_no_teardown, > + .set_shutdown = l2cap_chan_no_set_shutdown, please keep them in order as L2CAP socket does it. No need to mention that they are not implemented. The _no_ version of the empty helpers do that just fine. > +}; > + > +static struct l2cap_chan *chan_create(struct l2cap_conn *conn) > +{ > + struct l2cap_chan *chan; > + > + chan = l2cap_chan_create(); > + if (!chan) > + return NULL; > + > + l2cap_chan_set_defaults(chan); > + skb_queue_head_init(&chan->tx_q); I now wonder why the channel creation need to repeat the init of tx_q. > + > + chan->chan_type = L2CAP_CHAN_CONN_ORIENTED; > + chan->flush_to = L2CAP_DEFAULT_FLUSH_TO; > + chan->remote_max_tx = chan->max_tx; > + chan->remote_tx_win = chan->tx_win; > + chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO; > + chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO; Do we have to repeat the default here? Isn?t l2cap_chan_set_defaults already doing that? > + chan->mode = L2CAP_MODE_LE_FLOWCTL; > + chan->conf_state = 0; This one as well. Defaults should be in place. If not we need to fix the other code first to make sure we are clear here. Users of l2cap_ops should be as simple as possible. > + chan->omtu = chan->imtu = 65535; Personally I do not like the a = b = c assignments. Just use single assignments here. > + chan->ops = &bt_6lowpan_chan_ops; > + > + return chan; > +} > + > +static struct l2cap_chan *bt_6lowpan_channel_create(struct l2cap_conn *conn) > +{ > + struct lowpan_peer *peer; > + > + if (!is_bt_6lowpan(conn->hcon)) > + return NULL; > + > + BT_DBG("conn %p", conn); > + > + peer = lookup_peer(conn); > + if (peer) { > + BT_DBG("6LoWPAN connection and channel already exists"); > + return NULL; > + } > + > + return chan_create(conn); > +} > + > +static inline __u8 bdaddr_type(struct hci_conn *hcon, __u8 type) > +{ > + if (hcon->type == LE_LINK) { > + if (type == ADDR_LE_DEV_PUBLIC) > + return BDADDR_LE_PUBLIC; > + else > + return BDADDR_LE_RANDOM; > + } > + > + return BDADDR_BREDR; > +} > + > +void bt_6lowpan_check(struct l2cap_conn *conn) > +{ > + struct hci_conn *hcon = conn->hcon; > + struct l2cap_chan *pchan; > + u8 dst_type; > + int err; > + > + dst_type = bdaddr_type(hcon, hcon->dst_type); > + > + BT_DBG("conn %p dst type %d", conn, dst_type); > + > + if (hci_blacklist_lookup(hcon->hdev, &hcon->dst, dst_type)) > + return; > + > + pchan = bt_6lowpan_channel_create(conn); > + if (!pchan) > + return; > + > + if (test_bit(HCI_CONN_6LOWPAN_ROLE_NODE, &conn->hcon->flags)) { > + pchan->state = BT_LISTEN; > + pchan->src_type = bdaddr_type(hcon, hcon->src_type); > + > + err = l2cap_add_psm(pchan, &hcon->src, > + cpu_to_le16(L2CAP_PSM_6LOWPAN)); > + if (err) { > + BT_ERR("psm cannot be added err %d", err); > + return; > + } > + } else { > + err = l2cap_chan_connect(pchan, L2CAP_PSM_6LOWPAN, 0, > + &hcon->dst, dst_type); > + BT_DBG("chan %p err %d", pchan, err); > + } > } So I am thinking that just creating the 6loWPAN connection whenever we connect a LE link is not a good idea. Better have a debugfs trigger to manually create it. I am thinking the following: /sys/kernel/debug/bluetooth/hci0/6lowpan pam # sets PSM, 0 for disable (default) connect # connect 6loWPAN channel disconnect # disconnect 6loWPAN channel When reading that file it will show you the active 6loWPAN connections. This also means that all the hci_dev and hci_conn flags can go away and it is kept internally inside bluetooth_6lowpan.ko module. That will be pretty close to an API that we want to expose via mgmt at some point. > static int device_event(struct notifier_block *unused, > diff --git a/net/bluetooth/6lowpan.h b/net/bluetooth/6lowpan.h > index 5d281f1..1ba7af1 100644 > --- a/net/bluetooth/6lowpan.h > +++ b/net/bluetooth/6lowpan.h > @@ -1,5 +1,5 @@ > /* > - Copyright (c) 2013 Intel Corp. > + Copyright (c) 2014 Intel Corp. Same as above, 2013-2014. > > This program is free software; you can redistribute it and/or modify > it under the terms of the GNU General Public License version 2 and > @@ -19,29 +19,16 @@ > #include > > #if IS_ENABLED(CONFIG_BT_6LOWPAN) > -int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb); > -int bt_6lowpan_add_conn(struct l2cap_conn *conn); > -int bt_6lowpan_del_conn(struct l2cap_conn *conn); > int bt_6lowpan_init(void); > void bt_6lowpan_cleanup(void); > +void bt_6lowpan_check(struct l2cap_conn *conn); > #else > -static int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb) > -{ > - return -EOPNOTSUPP; > -} > -static int bt_6lowpan_add_conn(struct l2cap_conn *conn) > -{ > - return -EOPNOTSUPP; > -} > -int bt_6lowpan_del_conn(struct l2cap_conn *conn) > -{ > - return -EOPNOTSUPP; > -} > static int bt_6lowpan_init(void) > { > return -EOPNOTSUPP; > } > static void bt_6lowpan_cleanup(void) { } > +void bt_6lowpan_check(struct l2cap_conn *conn) { } > #endif With bluetooth_6lowpan.ko this should go away completely. > #endif /* __6LOWPAN_H */ > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c > index 528b38a..ef46498 100644 > --- a/net/bluetooth/l2cap_core.c > +++ b/net/bluetooth/l2cap_core.c > @@ -1454,8 +1454,6 @@ static void l2cap_le_conn_ready(struct l2cap_conn *conn) > > BT_DBG(""); > > - bt_6lowpan_add_conn(conn); > - > /* Check if we have socket listening on cid */ > pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_ATT, > &hcon->src, &hcon->dst); > @@ -1530,6 +1528,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn) > > mutex_unlock(&conn->chan_lock); > > + queue_work(hcon->hdev->workqueue, &conn->pending_6lowpan_work); > queue_work(hcon->hdev->workqueue, &conn->pending_rx_work); > } > > @@ -6945,10 +6944,6 @@ static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb) > l2cap_conn_del(conn->hcon, EACCES); > break; > > - case L2CAP_FC_6LOWPAN: > - bt_6lowpan_recv(conn, skb); > - break; > - > default: > l2cap_data_channel(conn, cid, skb); > break; > @@ -6967,6 +6962,15 @@ static void process_pending_rx(struct work_struct *work) > l2cap_recv_frame(conn, skb); > } > > +static void process_pending_6lowpan(struct work_struct *work) > +{ > + struct l2cap_conn *conn = container_of(work, struct l2cap_conn, > + pending_6lowpan_work); > + BT_DBG(""); > + > + bt_6lowpan_check(conn); > +} > + > static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) > { > struct l2cap_conn *conn = hcon->l2cap_data; > @@ -7024,6 +7028,7 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) > > skb_queue_head_init(&conn->pending_rx); > INIT_WORK(&conn->pending_rx_work, process_pending_rx); > + INIT_WORK(&conn->pending_6lowpan_work, process_pending_6lowpan); > > conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM; > > @@ -7257,8 +7262,6 @@ void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason) > { > BT_DBG("hcon %p reason %d", hcon, reason); > > - bt_6lowpan_del_conn(hcon->l2cap_data); > - > l2cap_conn_del(hcon, bt_to_errno(reason)); > } Regards Marcel