net/mac802154/main.c

   1 /*
   2  * Copyright (C) 2007-2012 Siemens AG
   3  *
   4  * Written by:
   5  * Alexander Smirnov <[email protected]>
   6  *
   7  * Based on the code from 'linux-zigbee.sourceforge.net' project.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2
  11  * as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/netdevice.h>
  22
  23 #include <net/netlink.h>
  24 #include <linux/nl802154.h>
  25 #include <net/mac802154.h>
  26 #include <net/ieee802154_netdev.h>
  27 #include <net/route.h>
  28 #include <net/cfg802154.h>
  29
  30 #include "ieee802154_i.h"
  31
  32 static int
  33 mac802154_netdev_register(struct wpan_phy *phy, struct net_device *dev)
  34 {
  35         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
  36         struct ieee802154_local *local;
  37         int err;
  38
  39         local = wpan_phy_priv(phy);
  40
  41         sdata->dev = dev;
  42         sdata->local = local;
  43
  44         dev->needed_headroom = local->hw.extra_tx_headroom;
  45
  46         SET_NETDEV_DEV(dev, &local->phy->dev);
  47
  48         err = register_netdev(dev);
  49         if (err < 0)
  50                 return err;
  51
  52         rtnl_lock();
  53         mutex_lock(&local->iflist_mtx);
  54         list_add_tail_rcu(&sdata->list, &local->interfaces);
  55         mutex_unlock(&local->iflist_mtx);
  56         rtnl_unlock();
  57
  58         return 0;
  59 }
  60
  61 static void
  62 mac802154_del_iface(struct wpan_phy *phy, struct net_device *dev)
  63 {
  64         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
  65
  66         ASSERT_RTNL();
  67
  68         BUG_ON(sdata->local->phy != phy);
  69
  70         mutex_lock(&sdata->local->iflist_mtx);
  71         list_del_rcu(&sdata->list);
  72         mutex_unlock(&sdata->local->iflist_mtx);
  73
  74         synchronize_rcu();
  75         unregister_netdevice(sdata->dev);
  76 }
  77
  78 static struct net_device *
  79 mac802154_add_iface(struct wpan_phy *phy, const char *name, int type)
  80 {
  81         struct net_device *dev;
  82         int err = -ENOMEM;
  83
  84         switch (type) {
  85         case IEEE802154_DEV_MONITOR:
  86                 dev = alloc_netdev(sizeof(struct ieee802154_sub_if_data),
  87                                    name, NET_NAME_UNKNOWN,
  88                                    mac802154_monitor_setup);
  89                 break;
  90         case IEEE802154_DEV_WPAN:
  91                 dev = alloc_netdev(sizeof(struct ieee802154_sub_if_data),
  92                                    name, NET_NAME_UNKNOWN,
  93                                    mac802154_wpan_setup);
  94                 break;
  95         default:
  96                 dev = NULL;
  97                 err = -EINVAL;
  98                 break;
  99         }
 100         if (!dev)
 101                 goto err;
 102
 103         err = mac802154_netdev_register(phy, dev);
 104         if (err)
 105                 goto err_free;
 106
 107         dev_hold(dev); /* we return an incremented device refcount */
 108         return dev;
 109
 110 err_free:
 111         free_netdev(dev);
 112 err:
 113         return ERR_PTR(err);
 114 }
 115
 116 static void ieee802154_tasklet_handler(unsigned long data)
 117 {
 118         struct ieee802154_local *local = (struct ieee802154_local *)data;
 119         struct sk_buff *skb;
 120
 121         while ((skb = skb_dequeue(&local->skb_queue))) {
 122                 switch (skb->pkt_type) {
 123                 case IEEE802154_RX_MSG:
 124                         /* Clear skb->pkt_type in order to not confuse kernel
 125                          * netstack.
 126                          */
 127                         skb->pkt_type = 0;
 128                         ieee802154_rx(&local->hw, skb);
 129                         break;
 130                 default:
 131                         WARN(1, "mac802154: Packet is of unknown type %d\n",
 132                              skb->pkt_type);
 133                         kfree_skb(skb);
 134                         break;
 135                 }
 136         }
 137 }
 138
 139 struct ieee802154_hw *
 140 ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
 141 {
 142         struct wpan_phy *phy;
 143         struct ieee802154_local *local;
 144         size_t priv_size;
 145
 146         if (!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
 147             !ops->start || !ops->stop || !ops->set_channel) {
 148                 pr_err("undefined IEEE802.15.4 device operations\n");
 149                 return NULL;
 150         }
 151
 152         /* Ensure 32-byte alignment of our private data and hw private data.
 153          * We use the wpan_phy priv data for both our ieee802154_local and for
 154          * the driver's private data
 155          *
 156          * in memory it'll be like this:
 157          *
 158          * +-------------------------+
 159          * | struct wpan_phy         |
 160          * +-------------------------+
 161          * | struct ieee802154_local |
 162          * +-------------------------+
 163          * | driver's private data   |
 164          * +-------------------------+
 165          *
 166          * Due to ieee802154 layer isn't aware of driver and MAC structures,
 167          * so lets align them here.
 168          */
 169
 170         priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
 171
 172         phy = wpan_phy_alloc(priv_size);
 173         if (!phy) {
 174                 pr_err("failure to allocate master IEEE802.15.4 device\n");
 175                 return NULL;
 176         }
 177
 178         local = wpan_phy_priv(phy);
 179         local->phy = phy;
 180         local->hw.phy = local->phy;
 181         local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
 182         local->ops = ops;
 183
 184         INIT_LIST_HEAD(&local->interfaces);
 185         mutex_init(&local->iflist_mtx);
 186
 187         tasklet_init(&local->tasklet,
 188                      ieee802154_tasklet_handler,
 189                      (unsigned long)local);
 190
 191         skb_queue_head_init(&local->skb_queue);
 192
 193         return &local->hw;
 194 }
 195 EXPORT_SYMBOL(ieee802154_alloc_hw);
 196
 197 void ieee802154_free_hw(struct ieee802154_hw *hw)
 198 {
 199         struct ieee802154_local *local = hw_to_local(hw);
 200
 201         BUG_ON(!list_empty(&local->interfaces));
 202
 203         mutex_destroy(&local->iflist_mtx);
 204
 205         wpan_phy_free(local->phy);
 206 }
 207 EXPORT_SYMBOL(ieee802154_free_hw);
 208
 209 int ieee802154_register_hw(struct ieee802154_hw *hw)
 210 {
 211         struct ieee802154_local *local = hw_to_local(hw);
 212         int rc = -ENOSYS;
 213
 214         local->workqueue =
 215                 create_singlethread_workqueue(wpan_phy_name(local->phy));
 216         if (!local->workqueue) {
 217                 rc = -ENOMEM;
 218                 goto out;
 219         }
 220
 221         wpan_phy_set_dev(local->phy, local->hw.parent);
 222
 223         local->phy->add_iface = mac802154_add_iface;
 224         local->phy->del_iface = mac802154_del_iface;
 225
 226         rc = wpan_phy_register(local->phy);
 227         if (rc < 0)
 228                 goto out_wq;
 229
 230         return 0;
 231
 232 out_wq:
 233         destroy_workqueue(local->workqueue);
 234 out:
 235         return rc;
 236 }
 237 EXPORT_SYMBOL(ieee802154_register_hw);
 238
 239 void ieee802154_unregister_hw(struct ieee802154_hw *hw)
 240 {
 241         struct ieee802154_local *local = hw_to_local(hw);
 242         struct ieee802154_sub_if_data *sdata, *next;
 243
 244         tasklet_kill(&local->tasklet);
 245         flush_workqueue(local->workqueue);
 246         destroy_workqueue(local->workqueue);
 247
 248         rtnl_lock();
 249
 250         list_for_each_entry_safe(sdata, next, &local->interfaces, list) {
 251                 mutex_lock(&sdata->local->iflist_mtx);
 252                 list_del(&sdata->list);
 253                 mutex_unlock(&sdata->local->iflist_mtx);
 254
 255                 unregister_netdevice(sdata->dev);
 256         }
 257
 258         rtnl_unlock();
 259
 260         wpan_phy_unregister(local->phy);
 261 }
 262 EXPORT_SYMBOL(ieee802154_unregister_hw);
 263
 264 MODULE_DESCRIPTION("IEEE 802.15.4 implementation");
 265 MODULE_LICENSE("GPL v2");