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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-25 20:17:34 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-25 20:17:34 +0100 |
commit | 4ba9920e5e9c0e16b5ed24292d45322907bb9035 (patch) | |
tree | 7d023baea59ed0886ded1f0b6d1c6385690b88f7 /net/bluetooth/6lowpan.c | |
parent | Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/ke... (diff) | |
parent | net/cxgb4: Fix referencing freed adapter (diff) | |
download | linux-4ba9920e5e9c0e16b5ed24292d45322907bb9035.tar.xz linux-4ba9920e5e9c0e16b5ed24292d45322907bb9035.zip |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
1) BPF debugger and asm tool by Daniel Borkmann.
2) Speed up create/bind in AF_PACKET, also from Daniel Borkmann.
3) Correct reciprocal_divide and update users, from Hannes Frederic
Sowa and Daniel Borkmann.
4) Currently we only have a "set" operation for the hw timestamp socket
ioctl, add a "get" operation to match. From Ben Hutchings.
5) Add better trace events for debugging driver datapath problems, also
from Ben Hutchings.
6) Implement auto corking in TCP, from Eric Dumazet. Basically, if we
have a small send and a previous packet is already in the qdisc or
device queue, defer until TX completion or we get more data.
7) Allow userspace to manage ipv6 temporary addresses, from Jiri Pirko.
8) Add a qdisc bypass option for AF_PACKET sockets, from Daniel
Borkmann.
9) Share IP header compression code between Bluetooth and IEEE802154
layers, from Jukka Rissanen.
10) Fix ipv6 router reachability probing, from Jiri Benc.
11) Allow packets to be captured on macvtap devices, from Vlad Yasevich.
12) Support tunneling in GRO layer, from Jerry Chu.
13) Allow bonding to be configured fully using netlink, from Scott
Feldman.
14) Allow AF_PACKET users to obtain the VLAN TPID, just like they can
already get the TCI. From Atzm Watanabe.
15) New "Heavy Hitter" qdisc, from Terry Lam.
16) Significantly improve the IPSEC support in pktgen, from Fan Du.
17) Allow ipv4 tunnels to cache routes, just like sockets. From Tom
Herbert.
18) Add Proportional Integral Enhanced packet scheduler, from Vijay
Subramanian.
19) Allow openvswitch to mmap'd netlink, from Thomas Graf.
20) Key TCP metrics blobs also by source address, not just destination
address. From Christoph Paasch.
21) Support 10G in generic phylib. From Andy Fleming.
22) Try to short-circuit GRO flow compares using device provided RX
hash, if provided. From Tom Herbert.
The wireless and netfilter folks have been busy little bees too.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2064 commits)
net/cxgb4: Fix referencing freed adapter
ipv6: reallocate addrconf router for ipv6 address when lo device up
fib_frontend: fix possible NULL pointer dereference
rtnetlink: remove IFLA_BOND_SLAVE definition
rtnetlink: remove check for fill_slave_info in rtnl_have_link_slave_info
qlcnic: update version to 5.3.55
qlcnic: Enhance logic to calculate msix vectors.
qlcnic: Refactor interrupt coalescing code for all adapters.
qlcnic: Update poll controller code path
qlcnic: Interrupt code cleanup
qlcnic: Enhance Tx timeout debugging.
qlcnic: Use bool for rx_mac_learn.
bonding: fix u64 division
rtnetlink: add missing IFLA_BOND_AD_INFO_UNSPEC
sfc: Use the correct maximum TX DMA ring size for SFC9100
Add Shradha Shah as the sfc driver maintainer.
net/vxlan: Share RX skb de-marking and checksum checks with ovs
tulip: cleanup by using ARRAY_SIZE()
ip_tunnel: clear IPCB in ip_tunnel_xmit() in case dst_link_failure() is called
net/cxgb4: Don't retrieve stats during recovery
...
Diffstat (limited to 'net/bluetooth/6lowpan.c')
-rw-r--r-- | net/bluetooth/6lowpan.c | 860 |
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); +} |