v4.19.13 snapshot.
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
new file mode 100644
index 0000000..4e2576f
--- /dev/null
+++ b/net/bluetooth/6lowpan.c
@@ -0,0 +1,1312 @@
+/*
+ Copyright (c) 2013-2014 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 <linux/module.h>
+#include <linux/debugfs.h>
+
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/pkt_sched.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/l2cap.h>
+
+#include <net/6lowpan.h> /* for the compression support */
+
+#define VERSION "0.1"
+
+static struct dentry *lowpan_enable_debugfs;
+static struct dentry *lowpan_control_debugfs;
+
+#define IFACE_NAME_TEMPLATE "bt%d"
+
+struct skb_cb {
+ struct in6_addr addr;
+ struct in6_addr gw;
+ struct l2cap_chan *chan;
+};
+#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_SPINLOCK(devices_lock);
+
+static bool enable_6lowpan;
+
+/* We are listening incoming connections via this channel
+ */
+static struct l2cap_chan *listen_chan;
+
+struct lowpan_peer {
+ struct list_head list;
+ struct rcu_head rcu;
+ struct l2cap_chan *chan;
+
+ /* peer addresses in various formats */
+ unsigned char lladdr[ETH_ALEN];
+ struct in6_addr peer_addr;
+};
+
+struct lowpan_btle_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_btle_dev *
+lowpan_btle_dev(const struct net_device *netdev)
+{
+ return (struct lowpan_btle_dev *)lowpan_dev(netdev)->priv;
+}
+
+static inline void peer_add(struct lowpan_btle_dev *dev,
+ struct lowpan_peer *peer)
+{
+ list_add_rcu(&peer->list, &dev->peers);
+ atomic_inc(&dev->peer_count);
+}
+
+static inline bool peer_del(struct lowpan_btle_dev *dev,
+ struct lowpan_peer *peer)
+{
+ list_del_rcu(&peer->list);
+ kfree_rcu(peer, rcu);
+
+ module_put(THIS_MODULE);
+
+ 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_btle_dev *dev,
+ bdaddr_t *ba, __u8 type)
+{
+ struct lowpan_peer *peer;
+
+ BT_DBG("peers %d addr %pMR type %d", atomic_read(&dev->peer_count),
+ ba, type);
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(peer, &dev->peers, list) {
+ BT_DBG("dst addr %pMR dst type %d",
+ &peer->chan->dst, peer->chan->dst_type);
+
+ if (bacmp(&peer->chan->dst, ba))
+ continue;
+
+ if (type == peer->chan->dst_type) {
+ rcu_read_unlock();
+ return peer;
+ }
+ }
+
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+static inline struct lowpan_peer *
+__peer_lookup_chan(struct lowpan_btle_dev *dev, struct l2cap_chan *chan)
+{
+ struct lowpan_peer *peer;
+
+ list_for_each_entry_rcu(peer, &dev->peers, list) {
+ if (peer->chan == chan)
+ return peer;
+ }
+
+ return NULL;
+}
+
+static inline struct lowpan_peer *
+__peer_lookup_conn(struct lowpan_btle_dev *dev, struct l2cap_conn *conn)
+{
+ struct lowpan_peer *peer;
+
+ list_for_each_entry_rcu(peer, &dev->peers, list) {
+ if (peer->chan->conn == conn)
+ return peer;
+ }
+
+ return NULL;
+}
+
+static inline struct lowpan_peer *peer_lookup_dst(struct lowpan_btle_dev *dev,
+ struct in6_addr *daddr,
+ struct sk_buff *skb)
+{
+ struct lowpan_peer *peer;
+ struct in6_addr *nexthop;
+ struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
+ int count = atomic_read(&dev->peer_count);
+
+ BT_DBG("peers %d addr %pI6c rt %p", count, daddr, rt);
+
+ /* If we have multiple 6lowpan peers, then check where we should
+ * send the packet. If only one peer exists, then we can send the
+ * packet right away.
+ */
+ if (count == 1) {
+ rcu_read_lock();
+ peer = list_first_or_null_rcu(&dev->peers, struct lowpan_peer,
+ list);
+ rcu_read_unlock();
+ return peer;
+ }
+
+ if (!rt) {
+ nexthop = &lowpan_cb(skb)->gw;
+
+ if (ipv6_addr_any(nexthop))
+ return NULL;
+ } else {
+ nexthop = rt6_nexthop(rt, daddr);
+
+ /* We need to remember the address because it is needed
+ * by bt_xmit() when sending the packet. In bt_xmit(), the
+ * destination routing info is not set.
+ */
+ memcpy(&lowpan_cb(skb)->gw, nexthop, sizeof(struct in6_addr));
+ }
+
+ BT_DBG("gw %pI6c", nexthop);
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(peer, &dev->peers, list) {
+ BT_DBG("dst addr %pMR dst type %d ip %pI6c",
+ &peer->chan->dst, peer->chan->dst_type,
+ &peer->peer_addr);
+
+ if (!ipv6_addr_cmp(&peer->peer_addr, nexthop)) {
+ rcu_read_unlock();
+ return peer;
+ }
+ }
+
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+static struct lowpan_peer *lookup_peer(struct l2cap_conn *conn)
+{
+ struct lowpan_btle_dev *entry;
+ struct lowpan_peer *peer = NULL;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ peer = __peer_lookup_conn(entry, conn);
+ if (peer)
+ break;
+ }
+
+ rcu_read_unlock();
+
+ return peer;
+}
+
+static struct lowpan_btle_dev *lookup_dev(struct l2cap_conn *conn)
+{
+ struct lowpan_btle_dev *entry;
+ struct lowpan_btle_dev *dev = NULL;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ if (conn->hcon->hdev == entry->hdev) {
+ dev = entry;
+ break;
+ }
+ }
+
+ rcu_read_unlock();
+
+ return dev;
+}
+
+static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sk_buff *skb_cp;
+
+ skb_cp = skb_copy(skb, GFP_ATOMIC);
+ if (!skb_cp)
+ return NET_RX_DROP;
+
+ return netif_rx_ni(skb_cp);
+}
+
+static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
+ struct lowpan_peer *peer)
+{
+ const u8 *saddr;
+
+ saddr = peer->lladdr;
+
+ return lowpan_header_decompress(skb, netdev, netdev->dev_addr, saddr);
+}
+
+static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
+ struct lowpan_peer *peer)
+{
+ struct sk_buff *local_skb;
+ int ret;
+
+ if (!netif_running(dev))
+ goto drop;
+
+ if (dev->type != ARPHRD_6LOWPAN || !skb->len)
+ goto drop;
+
+ skb_reset_network_header(skb);
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ goto drop;
+
+ /* check that it's our buffer */
+ if (lowpan_is_ipv6(*skb_network_header(skb))) {
+ /* Pull off the 1-byte of 6lowpan header. */
+ skb_pull(skb, 1);
+
+ /* 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;
+ local_skb->dev = dev;
+
+ 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++;
+
+ consume_skb(local_skb);
+ consume_skb(skb);
+ } else if (lowpan_is_iphc(*skb_network_header(skb))) {
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+
+ local_skb->dev = dev;
+
+ ret = iphc_decompress(local_skb, dev, peer);
+ if (ret < 0) {
+ BT_DBG("iphc_decompress failed: %d", ret);
+ kfree_skb(local_skb);
+ goto drop;
+ }
+
+ local_skb->protocol = htons(ETH_P_IPV6);
+ local_skb->pkt_type = PACKET_HOST;
+
+ 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++;
+
+ consume_skb(local_skb);
+ consume_skb(skb);
+ } else {
+ BT_DBG("unknown packet type");
+ goto drop;
+ }
+
+ return NET_RX_SUCCESS;
+
+drop:
+ dev->stats.rx_dropped++;
+ return NET_RX_DROP;
+}
+
+/* Packet from BT LE device */
+static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
+{
+ struct lowpan_btle_dev *dev;
+ struct lowpan_peer *peer;
+ int err;
+
+ peer = lookup_peer(chan->conn);
+ if (!peer)
+ return -ENOENT;
+
+ dev = lookup_dev(chan->conn);
+ if (!dev || !dev->netdev)
+ return -ENOENT;
+
+ err = recv_pkt(skb, dev->netdev, peer);
+ if (err) {
+ BT_DBG("recv pkt %d", err);
+ err = -EAGAIN;
+ }
+
+ return err;
+}
+
+static int setup_header(struct sk_buff *skb, struct net_device *netdev,
+ bdaddr_t *peer_addr, u8 *peer_addr_type)
+{
+ struct in6_addr ipv6_daddr;
+ struct ipv6hdr *hdr;
+ struct lowpan_btle_dev *dev;
+ struct lowpan_peer *peer;
+ u8 *daddr;
+ int err, status = 0;
+
+ hdr = ipv6_hdr(skb);
+
+ dev = lowpan_btle_dev(netdev);
+
+ memcpy(&ipv6_daddr, &hdr->daddr, sizeof(ipv6_daddr));
+
+ if (ipv6_addr_is_multicast(&ipv6_daddr)) {
+ lowpan_cb(skb)->chan = NULL;
+ daddr = NULL;
+ } else {
+ BT_DBG("dest IP %pI6c", &ipv6_daddr);
+
+ /* The packet might be sent to 6lowpan interface
+ * because of routing (either via default route
+ * or user set route) so get peer according to
+ * the destination address.
+ */
+ peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
+ if (!peer) {
+ BT_DBG("no such peer");
+ return -ENOENT;
+ }
+
+ daddr = peer->lladdr;
+ *peer_addr = peer->chan->dst;
+ *peer_addr_type = peer->chan->dst_type;
+ lowpan_cb(skb)->chan = peer->chan;
+
+ status = 1;
+ }
+
+ lowpan_header_compress(skb, netdev, daddr, dev->netdev->dev_addr);
+
+ err = dev_hard_header(skb, netdev, ETH_P_IPV6, NULL, NULL, 0);
+ if (err < 0)
+ return err;
+
+ return status;
+}
+
+static int header_create(struct sk_buff *skb, struct net_device *netdev,
+ unsigned short type, const void *_daddr,
+ const void *_saddr, unsigned int len)
+{
+ if (type != ETH_P_IPV6)
+ return -EINVAL;
+
+ return 0;
+}
+
+/* Packet to BT LE device */
+static int send_pkt(struct l2cap_chan *chan, struct sk_buff *skb,
+ struct net_device *netdev)
+{
+ struct msghdr msg;
+ struct kvec iv;
+ int err;
+
+ /* Remember the skb so that we can send EAGAIN to the caller if
+ * we run out of credits.
+ */
+ chan->data = skb;
+
+ iv.iov_base = skb->data;
+ iv.iov_len = skb->len;
+
+ memset(&msg, 0, sizeof(msg));
+ iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, skb->len);
+
+ err = l2cap_chan_send(chan, &msg, skb->len);
+ if (err > 0) {
+ netdev->stats.tx_bytes += err;
+ netdev->stats.tx_packets++;
+ return 0;
+ }
+
+ if (err < 0)
+ netdev->stats.tx_errors++;
+
+ return err;
+}
+
+static int send_mcast_pkt(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct sk_buff *local_skb;
+ struct lowpan_btle_dev *entry;
+ int err = 0;
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ struct lowpan_peer *pentry;
+ struct lowpan_btle_dev *dev;
+
+ if (entry->netdev != netdev)
+ continue;
+
+ dev = lowpan_btle_dev(entry->netdev);
+
+ list_for_each_entry_rcu(pentry, &dev->peers, list) {
+ int ret;
+
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+
+ BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
+ netdev->name,
+ &pentry->chan->dst, pentry->chan->dst_type,
+ &pentry->peer_addr, pentry->chan);
+ ret = send_pkt(pentry->chan, local_skb, netdev);
+ if (ret < 0)
+ err = ret;
+
+ kfree_skb(local_skb);
+ }
+ }
+
+ rcu_read_unlock();
+
+ return err;
+}
+
+static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+ int err = 0;
+ bdaddr_t addr;
+ u8 addr_type;
+
+ /* We must take a copy of the skb before we modify/replace the ipv6
+ * header as the header could be used elsewhere
+ */
+ skb = skb_unshare(skb, GFP_ATOMIC);
+ if (!skb)
+ return NET_XMIT_DROP;
+
+ /* Return values from setup_header()
+ * <0 - error, packet is dropped
+ * 0 - this is a multicast packet
+ * 1 - this is unicast packet
+ */
+ err = setup_header(skb, netdev, &addr, &addr_type);
+ if (err < 0) {
+ kfree_skb(skb);
+ return NET_XMIT_DROP;
+ }
+
+ if (err) {
+ if (lowpan_cb(skb)->chan) {
+ BT_DBG("xmit %s to %pMR type %d IP %pI6c chan %p",
+ netdev->name, &addr, addr_type,
+ &lowpan_cb(skb)->addr, lowpan_cb(skb)->chan);
+ err = send_pkt(lowpan_cb(skb)->chan, skb, netdev);
+ } else {
+ err = -ENOENT;
+ }
+ } else {
+ /* We need to send the packet to every device behind this
+ * interface.
+ */
+ err = send_mcast_pkt(skb, netdev);
+ }
+
+ dev_kfree_skb(skb);
+
+ if (err)
+ BT_DBG("ERROR: xmit failed (%d)", err);
+
+ return err < 0 ? NET_XMIT_DROP : err;
+}
+
+static int bt_dev_init(struct net_device *dev)
+{
+ netdev_lockdep_set_classes(dev);
+
+ return 0;
+}
+
+static const struct net_device_ops netdev_ops = {
+ .ndo_init = bt_dev_init,
+ .ndo_start_xmit = bt_xmit,
+};
+
+static struct header_ops header_ops = {
+ .create = header_create,
+};
+
+static void netdev_setup(struct net_device *dev)
+{
+ dev->hard_header_len = 0;
+ dev->needed_tailroom = 0;
+ dev->flags = IFF_RUNNING | IFF_MULTICAST;
+ dev->watchdog_timeo = 0;
+ dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
+
+ dev->netdev_ops = &netdev_ops;
+ dev->header_ops = &header_ops;
+ dev->needs_free_netdev = true;
+}
+
+static struct device_type bt_type = {
+ .name = "bluetooth",
+};
+
+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 ifdown(struct net_device *netdev)
+{
+ rtnl_lock();
+ dev_close(netdev);
+ rtnl_unlock();
+}
+
+static void do_notify_peers(struct work_struct *work)
+{
+ struct lowpan_btle_dev *dev = container_of(work, struct lowpan_btle_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;
+
+ if (!enable_6lowpan)
+ return false;
+
+ return true;
+}
+
+static struct l2cap_chan *chan_create(void)
+{
+ struct l2cap_chan *chan;
+
+ chan = l2cap_chan_create();
+ if (!chan)
+ return NULL;
+
+ l2cap_chan_set_defaults(chan);
+
+ chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
+ chan->mode = L2CAP_MODE_LE_FLOWCTL;
+ chan->imtu = 1280;
+
+ return chan;
+}
+
+static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
+ struct lowpan_btle_dev *dev,
+ bool new_netdev)
+{
+ struct lowpan_peer *peer;
+
+ peer = kzalloc(sizeof(*peer), GFP_ATOMIC);
+ if (!peer)
+ return NULL;
+
+ peer->chan = chan;
+ memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
+
+ baswap((void *)peer->lladdr, &chan->dst);
+
+ lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
+
+ spin_lock(&devices_lock);
+ INIT_LIST_HEAD(&peer->list);
+ peer_add(dev, peer);
+ spin_unlock(&devices_lock);
+
+ /* Notifying peers about us needs to be done without locks held */
+ if (new_netdev)
+ INIT_DELAYED_WORK(&dev->notify_peers, do_notify_peers);
+ schedule_delayed_work(&dev->notify_peers, msecs_to_jiffies(100));
+
+ return peer->chan;
+}
+
+static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
+{
+ struct net_device *netdev;
+ int err = 0;
+
+ netdev = alloc_netdev(LOWPAN_PRIV_SIZE(sizeof(struct lowpan_btle_dev)),
+ IFACE_NAME_TEMPLATE, NET_NAME_UNKNOWN,
+ netdev_setup);
+ if (!netdev)
+ return -ENOMEM;
+
+ netdev->addr_assign_type = NET_ADDR_PERM;
+ baswap((void *)netdev->dev_addr, &chan->src);
+
+ netdev->netdev_ops = &netdev_ops;
+ SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
+ SET_NETDEV_DEVTYPE(netdev, &bt_type);
+
+ *dev = lowpan_btle_dev(netdev);
+ (*dev)->netdev = netdev;
+ (*dev)->hdev = chan->conn->hcon->hdev;
+ INIT_LIST_HEAD(&(*dev)->peers);
+
+ spin_lock(&devices_lock);
+ INIT_LIST_HEAD(&(*dev)->list);
+ list_add_rcu(&(*dev)->list, &bt_6lowpan_devices);
+ spin_unlock(&devices_lock);
+
+ err = lowpan_register_netdev(netdev, LOWPAN_LLTYPE_BTLE);
+ if (err < 0) {
+ BT_INFO("register_netdev failed %d", err);
+ spin_lock(&devices_lock);
+ list_del_rcu(&(*dev)->list);
+ spin_unlock(&devices_lock);
+ free_netdev(netdev);
+ goto out;
+ }
+
+ BT_DBG("ifindex %d peer bdaddr %pMR type %d my addr %pMR type %d",
+ netdev->ifindex, &chan->dst, chan->dst_type,
+ &chan->src, chan->src_type);
+ set_bit(__LINK_STATE_PRESENT, &netdev->state);
+
+ return 0;
+
+out:
+ return err;
+}
+
+static inline void chan_ready_cb(struct l2cap_chan *chan)
+{
+ struct lowpan_btle_dev *dev;
+ bool new_netdev = false;
+
+ dev = lookup_dev(chan->conn);
+
+ BT_DBG("chan %p conn %p dev %p", chan, chan->conn, dev);
+
+ if (!dev) {
+ if (setup_netdev(chan, &dev) < 0) {
+ l2cap_chan_del(chan, -ENOENT);
+ return;
+ }
+ new_netdev = true;
+ }
+
+ if (!try_module_get(THIS_MODULE))
+ return;
+
+ add_peer_chan(chan, dev, new_netdev);
+ ifup(dev->netdev);
+}
+
+static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
+{
+ struct l2cap_chan *chan;
+
+ chan = chan_create();
+ if (!chan)
+ return NULL;
+
+ chan->ops = pchan->ops;
+
+ BT_DBG("chan %p pchan %p", chan, pchan);
+
+ return chan;
+}
+
+static void delete_netdev(struct work_struct *work)
+{
+ struct lowpan_btle_dev *entry = container_of(work,
+ struct lowpan_btle_dev,
+ delete_netdev);
+
+ lowpan_unregister_netdev(entry->netdev);
+
+ /* The entry pointer is deleted by the netdev destructor. */
+}
+
+static void chan_close_cb(struct l2cap_chan *chan)
+{
+ struct lowpan_btle_dev *entry;
+ struct lowpan_btle_dev *dev = NULL;
+ struct lowpan_peer *peer;
+ int err = -ENOENT;
+ bool last = false, remove = 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 set, then the netdev is also there and we should
+ * not remove it.
+ */
+ remove = false;
+ }
+
+ spin_lock(&devices_lock);
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ dev = lowpan_btle_dev(entry->netdev);
+ 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);
+ BT_DBG("chan %p orig refcnt %d", chan,
+ kref_read(&chan->kref));
+
+ l2cap_chan_put(chan);
+ break;
+ }
+ }
+
+ if (!err && last && dev && !atomic_read(&dev->peer_count)) {
+ spin_unlock(&devices_lock);
+
+ cancel_delayed_work_sync(&dev->notify_peers);
+
+ ifdown(dev->netdev);
+
+ if (remove) {
+ INIT_WORK(&entry->delete_netdev, delete_netdev);
+ schedule_work(&entry->delete_netdev);
+ }
+ } else {
+ spin_unlock(&devices_lock);
+ }
+
+ return;
+}
+
+static void chan_state_change_cb(struct l2cap_chan *chan, int state, int err)
+{
+ BT_DBG("chan %p conn %p state %s err %d", chan, chan->conn,
+ state_to_string(state), err);
+}
+
+static struct sk_buff *chan_alloc_skb_cb(struct l2cap_chan *chan,
+ unsigned long hdr_len,
+ unsigned long len, int nb)
+{
+ /* Note that we must allocate using GFP_ATOMIC here as
+ * this function is called originally from netdev hard xmit
+ * function in atomic context.
+ */
+ return bt_skb_alloc(hdr_len + len, GFP_ATOMIC);
+}
+
+static void chan_suspend_cb(struct l2cap_chan *chan)
+{
+ struct lowpan_btle_dev *dev;
+
+ BT_DBG("chan %p suspend", chan);
+
+ dev = lookup_dev(chan->conn);
+ if (!dev || !dev->netdev)
+ return;
+
+ netif_stop_queue(dev->netdev);
+}
+
+static void chan_resume_cb(struct l2cap_chan *chan)
+{
+ struct lowpan_btle_dev *dev;
+
+ BT_DBG("chan %p resume", chan);
+
+ dev = lookup_dev(chan->conn);
+ if (!dev || !dev->netdev)
+ return;
+
+ netif_wake_queue(dev->netdev);
+}
+
+static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
+{
+ return L2CAP_CONN_TIMEOUT;
+}
+
+static const struct l2cap_ops bt_6lowpan_chan_ops = {
+ .name = "L2CAP 6LoWPAN channel",
+ .new_connection = chan_new_conn_cb,
+ .recv = chan_recv_cb,
+ .close = chan_close_cb,
+ .state_change = chan_state_change_cb,
+ .ready = chan_ready_cb,
+ .resume = chan_resume_cb,
+ .suspend = chan_suspend_cb,
+ .get_sndtimeo = chan_get_sndtimeo_cb,
+ .alloc_skb = chan_alloc_skb_cb,
+
+ .teardown = l2cap_chan_no_teardown,
+ .defer = l2cap_chan_no_defer,
+ .set_shutdown = l2cap_chan_no_set_shutdown,
+};
+
+static inline __u8 bdaddr_type(__u8 type)
+{
+ if (type == ADDR_LE_DEV_PUBLIC)
+ return BDADDR_LE_PUBLIC;
+ else
+ return BDADDR_LE_RANDOM;
+}
+
+static int bt_6lowpan_connect(bdaddr_t *addr, u8 dst_type)
+{
+ struct l2cap_chan *chan;
+ int err;
+
+ chan = chan_create();
+ if (!chan)
+ return -EINVAL;
+
+ chan->ops = &bt_6lowpan_chan_ops;
+
+ err = l2cap_chan_connect(chan, cpu_to_le16(L2CAP_PSM_IPSP), 0,
+ addr, dst_type);
+
+ BT_DBG("chan %p err %d", chan, err);
+ if (err < 0)
+ l2cap_chan_put(chan);
+
+ return err;
+}
+
+static int bt_6lowpan_disconnect(struct l2cap_conn *conn, u8 dst_type)
+{
+ struct lowpan_peer *peer;
+
+ BT_DBG("conn %p dst type %d", conn, dst_type);
+
+ peer = lookup_peer(conn);
+ if (!peer)
+ return -ENOENT;
+
+ BT_DBG("peer %p chan %p", peer, peer->chan);
+
+ l2cap_chan_close(peer->chan, ENOENT);
+
+ return 0;
+}
+
+static struct l2cap_chan *bt_6lowpan_listen(void)
+{
+ bdaddr_t *addr = BDADDR_ANY;
+ struct l2cap_chan *chan;
+ int err;
+
+ if (!enable_6lowpan)
+ return NULL;
+
+ chan = chan_create();
+ if (!chan)
+ return NULL;
+
+ chan->ops = &bt_6lowpan_chan_ops;
+ chan->state = BT_LISTEN;
+ chan->src_type = BDADDR_LE_PUBLIC;
+
+ atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
+
+ BT_DBG("chan %p src type %d", chan, chan->src_type);
+
+ err = l2cap_add_psm(chan, addr, cpu_to_le16(L2CAP_PSM_IPSP));
+ if (err) {
+ l2cap_chan_put(chan);
+ BT_ERR("psm cannot be added err %d", err);
+ return NULL;
+ }
+
+ return chan;
+}
+
+static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
+ struct l2cap_conn **conn)
+{
+ struct hci_conn *hcon;
+ struct hci_dev *hdev;
+ int n;
+
+ n = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx %hhu",
+ &addr->b[5], &addr->b[4], &addr->b[3],
+ &addr->b[2], &addr->b[1], &addr->b[0],
+ addr_type);
+
+ if (n < 7)
+ return -EINVAL;
+
+ /* The LE_PUBLIC address type is ignored because of BDADDR_ANY */
+ hdev = hci_get_route(addr, BDADDR_ANY, BDADDR_LE_PUBLIC);
+ if (!hdev)
+ return -ENOENT;
+
+ hci_dev_lock(hdev);
+ hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
+ hci_dev_unlock(hdev);
+
+ if (!hcon)
+ return -ENOENT;
+
+ *conn = (struct l2cap_conn *)hcon->l2cap_data;
+
+ BT_DBG("conn %p dst %pMR type %d", *conn, &hcon->dst, hcon->dst_type);
+
+ return 0;
+}
+
+static void disconnect_all_peers(void)
+{
+ struct lowpan_btle_dev *entry;
+ struct lowpan_peer *peer, *tmp_peer, *new_peer;
+ struct list_head peers;
+
+ INIT_LIST_HEAD(&peers);
+
+ /* We make a separate list of peers as the close_cb() will
+ * modify the device peers list so it is better not to mess
+ * with the same list at the same time.
+ */
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ list_for_each_entry_rcu(peer, &entry->peers, list) {
+ new_peer = kmalloc(sizeof(*new_peer), GFP_ATOMIC);
+ if (!new_peer)
+ break;
+
+ new_peer->chan = peer->chan;
+ INIT_LIST_HEAD(&new_peer->list);
+
+ list_add(&new_peer->list, &peers);
+ }
+ }
+
+ rcu_read_unlock();
+
+ spin_lock(&devices_lock);
+ list_for_each_entry_safe(peer, tmp_peer, &peers, list) {
+ l2cap_chan_close(peer->chan, ENOENT);
+
+ list_del_rcu(&peer->list);
+ kfree_rcu(peer, rcu);
+ }
+ spin_unlock(&devices_lock);
+}
+
+struct set_enable {
+ struct work_struct work;
+ bool flag;
+};
+
+static void do_enable_set(struct work_struct *work)
+{
+ struct set_enable *set_enable = container_of(work,
+ struct set_enable, work);
+
+ if (!set_enable->flag || enable_6lowpan != set_enable->flag)
+ /* Disconnect existing connections if 6lowpan is
+ * disabled
+ */
+ disconnect_all_peers();
+
+ enable_6lowpan = set_enable->flag;
+
+ if (listen_chan) {
+ l2cap_chan_close(listen_chan, 0);
+ l2cap_chan_put(listen_chan);
+ }
+
+ listen_chan = bt_6lowpan_listen();
+
+ kfree(set_enable);
+}
+
+static int lowpan_enable_set(void *data, u64 val)
+{
+ struct set_enable *set_enable;
+
+ set_enable = kzalloc(sizeof(*set_enable), GFP_KERNEL);
+ if (!set_enable)
+ return -ENOMEM;
+
+ set_enable->flag = !!val;
+ INIT_WORK(&set_enable->work, do_enable_set);
+
+ schedule_work(&set_enable->work);
+
+ return 0;
+}
+
+static int lowpan_enable_get(void *data, u64 *val)
+{
+ *val = enable_6lowpan;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(lowpan_enable_fops, lowpan_enable_get,
+ lowpan_enable_set, "%llu\n");
+
+static ssize_t lowpan_control_write(struct file *fp,
+ const char __user *user_buffer,
+ size_t count,
+ loff_t *position)
+{
+ char buf[32];
+ size_t buf_size = min(count, sizeof(buf) - 1);
+ int ret;
+ bdaddr_t addr;
+ u8 addr_type;
+ struct l2cap_conn *conn = NULL;
+
+ if (copy_from_user(buf, user_buffer, buf_size))
+ return -EFAULT;
+
+ buf[buf_size] = '\0';
+
+ if (memcmp(buf, "connect ", 8) == 0) {
+ ret = get_l2cap_conn(&buf[8], &addr, &addr_type, &conn);
+ if (ret == -EINVAL)
+ return ret;
+
+ if (listen_chan) {
+ l2cap_chan_close(listen_chan, 0);
+ l2cap_chan_put(listen_chan);
+ listen_chan = NULL;
+ }
+
+ if (conn) {
+ struct lowpan_peer *peer;
+
+ if (!is_bt_6lowpan(conn->hcon))
+ return -EINVAL;
+
+ peer = lookup_peer(conn);
+ if (peer) {
+ BT_DBG("6LoWPAN connection already exists");
+ return -EALREADY;
+ }
+
+ BT_DBG("conn %p dst %pMR type %d user %d", conn,
+ &conn->hcon->dst, conn->hcon->dst_type,
+ addr_type);
+ }
+
+ ret = bt_6lowpan_connect(&addr, addr_type);
+ if (ret < 0)
+ return ret;
+
+ return count;
+ }
+
+ if (memcmp(buf, "disconnect ", 11) == 0) {
+ ret = get_l2cap_conn(&buf[11], &addr, &addr_type, &conn);
+ if (ret < 0)
+ return ret;
+
+ ret = bt_6lowpan_disconnect(conn, addr_type);
+ if (ret < 0)
+ return ret;
+
+ return count;
+ }
+
+ return count;
+}
+
+static int lowpan_control_show(struct seq_file *f, void *ptr)
+{
+ struct lowpan_btle_dev *entry;
+ struct lowpan_peer *peer;
+
+ spin_lock(&devices_lock);
+
+ list_for_each_entry(entry, &bt_6lowpan_devices, list) {
+ list_for_each_entry(peer, &entry->peers, list)
+ seq_printf(f, "%pMR (type %u)\n",
+ &peer->chan->dst, peer->chan->dst_type);
+ }
+
+ spin_unlock(&devices_lock);
+
+ return 0;
+}
+
+static int lowpan_control_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, lowpan_control_show, inode->i_private);
+}
+
+static const struct file_operations lowpan_control_fops = {
+ .open = lowpan_control_open,
+ .read = seq_read,
+ .write = lowpan_control_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void disconnect_devices(void)
+{
+ struct lowpan_btle_dev *entry, *tmp, *new_dev;
+ struct list_head devices;
+
+ INIT_LIST_HEAD(&devices);
+
+ /* We make a separate list of devices because the unregister_netdev()
+ * will call device_event() which will also want to modify the same
+ * devices list.
+ */
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(entry, &bt_6lowpan_devices, list) {
+ new_dev = kmalloc(sizeof(*new_dev), GFP_ATOMIC);
+ if (!new_dev)
+ break;
+
+ new_dev->netdev = entry->netdev;
+ INIT_LIST_HEAD(&new_dev->list);
+
+ list_add_rcu(&new_dev->list, &devices);
+ }
+
+ rcu_read_unlock();
+
+ list_for_each_entry_safe(entry, tmp, &devices, list) {
+ ifdown(entry->netdev);
+ BT_DBG("Unregistering netdev %s %p",
+ entry->netdev->name, entry->netdev);
+ lowpan_unregister_netdev(entry->netdev);
+ kfree(entry);
+ }
+}
+
+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_btle_dev *entry;
+
+ if (netdev->type != ARPHRD_6LOWPAN)
+ return NOTIFY_DONE;
+
+ switch (event) {
+ case NETDEV_UNREGISTER:
+ spin_lock(&devices_lock);
+ list_for_each_entry(entry, &bt_6lowpan_devices, list) {
+ if (entry->netdev == netdev) {
+ BT_DBG("Unregistered netdev %s %p",
+ netdev->name, netdev);
+ list_del(&entry->list);
+ break;
+ }
+ }
+ spin_unlock(&devices_lock);
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block bt_6lowpan_dev_notifier = {
+ .notifier_call = device_event,
+};
+
+static int __init bt_6lowpan_init(void)
+{
+ lowpan_enable_debugfs = debugfs_create_file("6lowpan_enable", 0644,
+ bt_debugfs, NULL,
+ &lowpan_enable_fops);
+ lowpan_control_debugfs = debugfs_create_file("6lowpan_control", 0644,
+ bt_debugfs, NULL,
+ &lowpan_control_fops);
+
+ return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}
+
+static void __exit bt_6lowpan_exit(void)
+{
+ debugfs_remove(lowpan_enable_debugfs);
+ debugfs_remove(lowpan_control_debugfs);
+
+ if (listen_chan) {
+ l2cap_chan_close(listen_chan, 0);
+ l2cap_chan_put(listen_chan);
+ }
+
+ disconnect_devices();
+
+ unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}
+
+module_init(bt_6lowpan_init);
+module_exit(bt_6lowpan_exit);
+
+MODULE_AUTHOR("Jukka Rissanen <jukka.rissanen@linux.intel.com>");
+MODULE_DESCRIPTION("Bluetooth 6LoWPAN");
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");