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-rw-r--r--net/bluetooth/6lowpan.c860
1 files changed, 860 insertions, 0 deletions
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
new file mode 100644
index 000000000000..adb3ea04adaa
--- /dev/null
+++ b/net/bluetooth/6lowpan.c
@@ -0,0 +1,860 @@
+/*
+ Copyright (c) 2013 Intel Corp.
+
+ 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
+ only version 2 as published by the Free Software Foundation.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+*/
+
+#include <linux/if_arp.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+
+#include <net/af_ieee802154.h> /* to get the address type */
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/l2cap.h>
+
+#include "6lowpan.h"
+
+#include "../ieee802154/6lowpan.h" /* for the compression support */
+
+#define IFACE_NAME_TEMPLATE "bt%d"
+#define EUI64_ADDR_LEN 8
+
+struct skb_cb {
+ struct in6_addr addr;
+ struct l2cap_conn *conn;
+};
+#define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb))
+
+/* The devices list contains those devices that we are acting
+ * as a proxy. The BT 6LoWPAN device is a virtual device that
+ * connects to the Bluetooth LE device. The real connection to
+ * BT device is done via l2cap layer. There exists one
+ * virtual device / one BT 6LoWPAN network (=hciX device).
+ * The list contains struct lowpan_dev elements.
+ */
+static LIST_HEAD(bt_6lowpan_devices);
+static DEFINE_RWLOCK(devices_lock);
+
+struct lowpan_peer {
+ struct list_head list;
+ struct l2cap_conn *conn;
+
+ /* peer addresses in various formats */
+ unsigned char eui64_addr[EUI64_ADDR_LEN];
+ struct in6_addr peer_addr;
+};
+
+struct lowpan_dev {
+ struct list_head list;
+
+ struct hci_dev *hdev;
+ struct net_device *netdev;
+ struct list_head peers;
+ atomic_t peer_count; /* number of items in peers list */
+
+ struct work_struct delete_netdev;
+ struct delayed_work notify_peers;
+};
+
+static inline struct lowpan_dev *lowpan_dev(const struct net_device *netdev)
+{
+ return netdev_priv(netdev);
+}
+
+static inline void peer_add(struct lowpan_dev *dev, struct lowpan_peer *peer)
+{
+ list_add(&peer->list, &dev->peers);
+ atomic_inc(&dev->peer_count);
+}
+
+static inline bool peer_del(struct lowpan_dev *dev, struct lowpan_peer *peer)
+{
+ list_del(&peer->list);
+
+ if (atomic_dec_and_test(&dev->peer_count)) {
+ BT_DBG("last peer");
+ return true;
+ }
+
+ return false;
+}
+
+static inline struct lowpan_peer *peer_lookup_ba(struct lowpan_dev *dev,
+ bdaddr_t *ba, __u8 type)
+{
+ struct lowpan_peer *peer, *tmp;
+
+ BT_DBG("peers %d addr %pMR type %d", atomic_read(&dev->peer_count),
+ ba, type);
+
+ 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);
+
+ if (bacmp(&peer->conn->hcon->dst, ba))
+ continue;
+
+ if (type == peer->conn->hcon->dst_type)
+ return peer;
+ }
+
+ return NULL;
+}
+
+static inline struct lowpan_peer *peer_lookup_conn(struct lowpan_dev *dev,
+ struct l2cap_conn *conn)
+{
+ struct lowpan_peer *peer, *tmp;
+
+ list_for_each_entry_safe(peer, tmp, &dev->peers, list) {
+ if (peer->conn == conn)
+ return peer;
+ }
+
+ return NULL;
+}
+
+static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
+{
+ struct lowpan_dev *entry, *tmp;
+ struct lowpan_peer *peer = NULL;
+ unsigned long flags;
+
+ read_lock_irqsave(&devices_lock, flags);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ peer = peer_lookup_conn(entry, conn);
+ if (peer)
+ break;
+ }
+
+ read_unlock_irqrestore(&devices_lock, flags);
+
+ return peer;
+}
+
+static struct lowpan_dev *lookup_dev(struct l2cap_conn *conn)
+{
+ struct lowpan_dev *entry, *tmp;
+ struct lowpan_dev *dev = NULL;
+ unsigned long flags;
+
+ read_lock_irqsave(&devices_lock, flags);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ if (conn->hcon->hdev == entry->hdev) {
+ dev = entry;
+ break;
+ }
+ }
+
+ read_unlock_irqrestore(&devices_lock, flags);
+
+ return dev;
+}
+
+static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sk_buff *skb_cp;
+ int ret;
+
+ skb_cp = skb_copy(skb, GFP_ATOMIC);
+ if (!skb_cp)
+ return -ENOMEM;
+
+ ret = netif_rx(skb_cp);
+
+ BT_DBG("receive skb %d", ret);
+ if (ret < 0)
+ return NET_RX_DROP;
+
+ return ret;
+}
+
+static int process_data(struct sk_buff *skb, struct net_device *netdev,
+ struct l2cap_conn *conn)
+{
+ const u8 *saddr, *daddr;
+ u8 iphc0, iphc1;
+ struct lowpan_dev *dev;
+ struct lowpan_peer *peer;
+ unsigned long flags;
+
+ dev = lowpan_dev(netdev);
+
+ read_lock_irqsave(&devices_lock, flags);
+ peer = peer_lookup_conn(dev, conn);
+ read_unlock_irqrestore(&devices_lock, flags);
+ if (!peer)
+ goto drop;
+
+ saddr = peer->eui64_addr;
+ daddr = dev->netdev->dev_addr;
+
+ /* at least two bytes will be used for the encoding */
+ if (skb->len < 2)
+ goto drop;
+
+ if (lowpan_fetch_skb_u8(skb, &iphc0))
+ goto drop;
+
+ if (lowpan_fetch_skb_u8(skb, &iphc1))
+ goto drop;
+
+ return lowpan_process_data(skb, netdev,
+ saddr, IEEE802154_ADDR_LONG, EUI64_ADDR_LEN,
+ daddr, IEEE802154_ADDR_LONG, EUI64_ADDR_LEN,
+ iphc0, iphc1, give_skb_to_upper);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
+ struct l2cap_conn *conn)
+{
+ struct sk_buff *local_skb;
+ int ret;
+
+ if (!netif_running(dev))
+ goto drop;
+
+ if (dev->type != ARPHRD_6LOWPAN)
+ goto drop;
+
+ /* check that it's our buffer */
+ if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
+ /* Copy the packet so that the IPv6 header is
+ * properly aligned.
+ */
+ local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
+ skb_tailroom(skb), GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+
+ local_skb->protocol = htons(ETH_P_IPV6);
+ local_skb->pkt_type = PACKET_HOST;
+
+ skb_reset_network_header(local_skb);
+ skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
+
+ if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
+ kfree_skb(local_skb);
+ goto drop;
+ }
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(local_skb);
+ kfree_skb(skb);
+ } else {
+ switch (skb->data[0] & 0xe0) {
+ case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+
+ ret = process_data(local_skb, dev, conn);
+ if (ret != NET_RX_SUCCESS)
+ goto drop;
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(skb);
+ break;
+ default:
+ break;
+ }
+ }
+
+ return NET_RX_SUCCESS;
+
+drop:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+/* Packet from BT LE device */
+int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+ struct lowpan_dev *dev;
+ struct lowpan_peer *peer;
+ int err;
+
+ peer = lookup_peer(conn);
+ if (!peer)
+ return -ENOENT;
+
+ dev = lookup_dev(conn);
+ if (!dev || !dev->netdev)
+ return -ENOENT;
+
+ err = recv_pkt(skb, dev->netdev, conn);
+ 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)
+{
+ u8 *eui64;
+
+ eui64 = ip6_daddr->s6_addr + 8;
+
+ addr->b[0] = eui64[7];
+ addr->b[1] = eui64[6];
+ addr->b[2] = eui64[5];
+ addr->b[3] = eui64[2];
+ addr->b[4] = eui64[1];
+ addr->b[5] = eui64[0];
+
+ addr->b[5] ^= 2;
+
+ /* Set universal/local bit to 0 */
+ if (addr->b[5] & 1) {
+ addr->b[5] &= ~1;
+ *addr_type = ADDR_LE_DEV_PUBLIC;
+ } else {
+ *addr_type = ADDR_LE_DEV_RANDOM;
+ }
+}
+
+static int header_create(struct sk_buff *skb, struct net_device *netdev,
+ unsigned short type, const void *_daddr,
+ const void *_saddr, unsigned int len)
+{
+ struct ipv6hdr *hdr;
+ struct lowpan_dev *dev;
+ struct lowpan_peer *peer;
+ bdaddr_t addr, *any = BDADDR_ANY;
+ u8 *saddr, *daddr = any->b;
+ u8 addr_type;
+
+ if (type != ETH_P_IPV6)
+ return -EINVAL;
+
+ hdr = ipv6_hdr(skb);
+
+ dev = lowpan_dev(netdev);
+
+ if (ipv6_addr_is_multicast(&hdr->daddr)) {
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = NULL;
+ } else {
+ unsigned long flags;
+
+ /* Get destination BT device from skb.
+ * If there is no such peer then discard the packet.
+ */
+ get_dest_bdaddr(&hdr->daddr, &addr, &addr_type);
+
+ BT_DBG("dest addr %pMR type %d", &addr, addr_type);
+
+ read_lock_irqsave(&devices_lock, flags);
+ peer = peer_lookup_ba(dev, &addr, addr_type);
+ read_unlock_irqrestore(&devices_lock, flags);
+
+ if (!peer) {
+ BT_DBG("no such peer %pMR found", &addr);
+ return -ENOENT;
+ }
+
+ daddr = peer->eui64_addr;
+
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = peer->conn;
+ }
+
+ saddr = dev->netdev->dev_addr;
+
+ return lowpan_header_compress(skb, netdev, type, daddr, saddr, len);
+}
+
+/* Packet to BT LE device */
+static int send_pkt(struct l2cap_conn *conn, 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);
+
+ return conn_send(conn, skb->data, skb->len, 0, netdev);
+}
+
+static void send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct sk_buff *local_skb;
+ struct lowpan_dev *entry, *tmp;
+ unsigned long flags;
+
+ read_lock_irqsave(&devices_lock, flags);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ struct lowpan_peer *pentry, *ptmp;
+ struct lowpan_dev *dev;
+
+ if (entry->netdev != netdev)
+ continue;
+
+ dev = lowpan_dev(entry->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,
+ pentry->eui64_addr, local_skb, netdev);
+
+ kfree_skb(local_skb);
+ }
+ }
+
+ read_unlock_irqrestore(&devices_lock, flags);
+}
+
+static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+ int err = 0;
+ unsigned char *eui64_addr;
+ struct lowpan_dev *dev;
+ struct lowpan_peer *peer;
+ bdaddr_t addr;
+ u8 addr_type;
+
+ if (ipv6_addr_is_multicast(&lowpan_cb(skb)->addr)) {
+ /* We need to send the packet to every device
+ * behind this interface.
+ */
+ send_mcast_pkt(skb, netdev);
+ } else {
+ unsigned long flags;
+
+ get_dest_bdaddr(&lowpan_cb(skb)->addr, &addr, &addr_type);
+ eui64_addr = lowpan_cb(skb)->addr.s6_addr + 8;
+ dev = lowpan_dev(netdev);
+
+ read_lock_irqsave(&devices_lock, flags);
+ peer = peer_lookup_ba(dev, &addr, addr_type);
+ read_unlock_irqrestore(&devices_lock, flags);
+
+ 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,
+ eui64_addr, skb, netdev);
+ }
+ dev_kfree_skb(skb);
+
+ if (err)
+ BT_DBG("ERROR: xmit failed (%d)", err);
+
+ return (err < 0) ? NET_XMIT_DROP : err;
+}
+
+static const struct net_device_ops netdev_ops = {
+ .ndo_start_xmit = bt_xmit,
+};
+
+static struct header_ops header_ops = {
+ .create = header_create,
+};
+
+static void netdev_setup(struct net_device *dev)
+{
+ dev->addr_len = EUI64_ADDR_LEN;
+ dev->type = ARPHRD_6LOWPAN;
+
+ dev->hard_header_len = 0;
+ dev->needed_tailroom = 0;
+ dev->mtu = IPV6_MIN_MTU;
+ dev->tx_queue_len = 0;
+ dev->flags = IFF_RUNNING | IFF_POINTOPOINT;
+ dev->watchdog_timeo = 0;
+
+ dev->netdev_ops = &netdev_ops;
+ dev->header_ops = &header_ops;
+ dev->destructor = free_netdev;
+}
+
+static struct device_type bt_type = {
+ .name = "bluetooth",
+};
+
+static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
+{
+ /* addr is the BT address in little-endian format */
+ eui[0] = addr[5];
+ eui[1] = addr[4];
+ eui[2] = addr[3];
+ eui[3] = 0xFF;
+ eui[4] = 0xFE;
+ eui[5] = addr[2];
+ eui[6] = addr[1];
+ eui[7] = addr[0];
+
+ eui[0] ^= 2;
+
+ /* Universal/local bit set, RFC 4291 */
+ if (addr_type == ADDR_LE_DEV_PUBLIC)
+ eui[0] |= 1;
+ else
+ eui[0] &= ~1;
+}
+
+static void set_dev_addr(struct net_device *netdev, bdaddr_t *addr,
+ u8 addr_type)
+{
+ netdev->addr_assign_type = NET_ADDR_PERM;
+ set_addr(netdev->dev_addr, addr->b, addr_type);
+ netdev->dev_addr[0] ^= 2;
+}
+
+static void ifup(struct net_device *netdev)
+{
+ int err;
+
+ rtnl_lock();
+ err = dev_open(netdev);
+ if (err < 0)
+ BT_INFO("iface %s cannot be opened (%d)", netdev->name, err);
+ rtnl_unlock();
+}
+
+static void do_notify_peers(struct work_struct *work)
+{
+ struct lowpan_dev *dev = container_of(work, struct lowpan_dev,
+ notify_peers.work);
+
+ netdev_notify_peers(dev->netdev); /* send neighbour adv at startup */
+}
+
+static bool is_bt_6lowpan(struct hci_conn *hcon)
+{
+ if (hcon->type != LE_LINK)
+ return false;
+
+ return test_bit(HCI_CONN_6LOWPAN, &hcon->flags);
+}
+
+static int add_peer_conn(struct l2cap_conn *conn, struct lowpan_dev *dev)
+{
+ struct lowpan_peer *peer;
+ unsigned long flags;
+
+ peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
+ if (!peer)
+ return -ENOMEM;
+
+ peer->conn = conn;
+ 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);
+
+ memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
+ EUI64_ADDR_LEN);
+ peer->eui64_addr[0] ^= 2; /* second bit-flip (Universe/Local)
+ * is done according RFC2464
+ */
+
+ raw_dump_inline(__func__, "peer IPv6 address",
+ (unsigned char *)&peer->peer_addr, 16);
+ raw_dump_inline(__func__, "peer EUI64 address", peer->eui64_addr, 8);
+
+ write_lock_irqsave(&devices_lock, flags);
+ INIT_LIST_HEAD(&peer->list);
+ peer_add(dev, peer);
+ write_unlock_irqrestore(&devices_lock, flags);
+
+ /* Notifying peers about us needs to be done without locks held */
+ INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
+ schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
+
+ return 0;
+}
+
+/* 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)
+{
+ 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);
+ if (!netdev)
+ return -ENOMEM;
+
+ set_dev_addr(netdev, &conn->hcon->src, conn->hcon->src_type);
+
+ netdev->netdev_ops = &netdev_ops;
+ SET_NETDEV_DEV(netdev, &conn->hcon->dev);
+ SET_NETDEV_DEVTYPE(netdev, &bt_type);
+
+ err = register_netdev(netdev);
+ if (err < 0) {
+ BT_INFO("register_netdev failed %d", err);
+ free_netdev(netdev);
+ goto out;
+ }
+
+ BT_DBG("ifindex %d peer bdaddr %pMR my addr %pMR",
+ 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);
+
+ write_lock_irqsave(&devices_lock, flags);
+ 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);
+
+out:
+ return err;
+}
+
+static void delete_netdev(struct work_struct *work)
+{
+ struct lowpan_dev *entry = container_of(work, struct lowpan_dev,
+ delete_netdev);
+
+ unregister_netdev(entry->netdev);
+
+ /* The entry pointer is deleted in device_event() */
+}
+
+int bt_6lowpan_del_conn(struct l2cap_conn *conn)
+{
+ struct lowpan_dev *entry, *tmp;
+ struct lowpan_dev *dev = NULL;
+ struct lowpan_peer *peer;
+ int err = -ENOENT;
+ unsigned long flags;
+ bool last = false;
+
+ if (!conn || !is_bt_6lowpan(conn->hcon))
+ return 0;
+
+ 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);
+ if (peer) {
+ last = peer_del(dev, peer);
+ err = 0;
+ break;
+ }
+ }
+
+ if (!err && last && dev && !atomic_read(&dev->peer_count)) {
+ write_unlock_irqrestore(&devices_lock, flags);
+
+ 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);
+ } else {
+ write_unlock_irqrestore(&devices_lock, flags);
+ }
+
+ return err;
+}
+
+static int device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
+ struct lowpan_dev *entry, *tmp;
+ unsigned long flags;
+
+ if (netdev->type != ARPHRD_6LOWPAN)
+ return NOTIFY_DONE;
+
+ switch (event) {
+ case NETDEV_UNREGISTER:
+ write_lock_irqsave(&devices_lock, flags);
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices,
+ list) {
+ if (entry->netdev == netdev) {
+ list_del(&entry->list);
+ kfree(entry);
+ break;
+ }
+ }
+ write_unlock_irqrestore(&devices_lock, flags);
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block bt_6lowpan_dev_notifier = {
+ .notifier_call = device_event,
+};
+
+int bt_6lowpan_init(void)
+{
+ return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}
+
+void bt_6lowpan_cleanup(void)
+{
+ unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}