git.oblomov.eu Git - linux-2.6/blob - drivers/net/wireless/mac80211_hwsim.c

   1 /*
   2  * mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
   3  * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 /*
  11  * TODO:
  12  * - IBSS mode simulation (Beacon transmission with competition for "air time")
  13  * - IEEE 802.11a and 802.11n modes
  14  * - RX filtering based on filter configuration (data->rx_filter)
  15  */
  16
  17 #include <linux/list.h>
  18 #include <linux/spinlock.h>
  19 #include <net/mac80211.h>
  20 #include <net/ieee80211_radiotap.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/rtnetlink.h>
  23 #include <linux/etherdevice.h>
  24
  25 MODULE_AUTHOR("Jouni Malinen");
  26 MODULE_DESCRIPTION("Software simulator of 802.11 radio(s) for mac80211");
  27 MODULE_LICENSE("GPL");
  28
  29 static int radios = 2;
  30 module_param(radios, int, 0444);
  31 MODULE_PARM_DESC(radios, "Number of simulated radios");
  32
  33 struct hwsim_vif_priv {
  34         u32 magic;
  35 };
  36
  37 #define HWSIM_VIF_MAGIC 0x69537748
  38
  39 static inline void hwsim_check_magic(struct ieee80211_vif *vif)
  40 {
  41         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  42         WARN_ON(vp->magic != HWSIM_VIF_MAGIC);
  43 }
  44
  45 static inline void hwsim_set_magic(struct ieee80211_vif *vif)
  46 {
  47         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  48         vp->magic = HWSIM_VIF_MAGIC;
  49 }
  50
  51 static inline void hwsim_clear_magic(struct ieee80211_vif *vif)
  52 {
  53         struct hwsim_vif_priv *vp = (void *)vif->drv_priv;
  54         vp->magic = 0;
  55 }
  56
  57 struct hwsim_sta_priv {
  58         u32 magic;
  59 };
  60
  61 #define HWSIM_STA_MAGIC 0x6d537748
  62
  63 static inline void hwsim_check_sta_magic(struct ieee80211_sta *sta)
  64 {
  65         struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
  66         WARN_ON(sp->magic != HWSIM_VIF_MAGIC);
  67 }
  68
  69 static inline void hwsim_set_sta_magic(struct ieee80211_sta *sta)
  70 {
  71         struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
  72         sp->magic = HWSIM_VIF_MAGIC;
  73 }
  74
  75 static inline void hwsim_clear_sta_magic(struct ieee80211_sta *sta)
  76 {
  77         struct hwsim_sta_priv *sp = (void *)sta->drv_priv;
  78         sp->magic = 0;
  79 }
  80
  81 static struct class *hwsim_class;
  82
  83 static struct net_device *hwsim_mon; /* global monitor netdev */
  84
  85
  86 static const struct ieee80211_channel hwsim_channels[] = {
  87         { .center_freq = 2412 },
  88         { .center_freq = 2417 },
  89         { .center_freq = 2422 },
  90         { .center_freq = 2427 },
  91         { .center_freq = 2432 },
  92         { .center_freq = 2437 },
  93         { .center_freq = 2442 },
  94         { .center_freq = 2447 },
  95         { .center_freq = 2452 },
  96         { .center_freq = 2457 },
  97         { .center_freq = 2462 },
  98         { .center_freq = 2467 },
  99         { .center_freq = 2472 },
 100         { .center_freq = 2484 },
 101 };
 102
 103 static const struct ieee80211_rate hwsim_rates[] = {
 104         { .bitrate = 10 },
 105         { .bitrate = 20, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 106         { .bitrate = 55, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 107         { .bitrate = 110, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
 108         { .bitrate = 60 },
 109         { .bitrate = 90 },
 110         { .bitrate = 120 },
 111         { .bitrate = 180 },
 112         { .bitrate = 240 },
 113         { .bitrate = 360 },
 114         { .bitrate = 480 },
 115         { .bitrate = 540 }
 116 };
 117
 118 static spinlock_t hwsim_radio_lock;
 119 static struct list_head hwsim_radios;
 120
 121 struct mac80211_hwsim_data {
 122         struct list_head list;
 123         struct ieee80211_hw *hw;
 124         struct device *dev;
 125         struct ieee80211_supported_band band;
 126         struct ieee80211_channel channels[ARRAY_SIZE(hwsim_channels)];
 127         struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];
 128
 129         struct ieee80211_channel *channel;
 130         int radio_enabled;
 131         unsigned long beacon_int; /* in jiffies unit */
 132         unsigned int rx_filter;
 133         int started;
 134         struct timer_list beacon_timer;
 135 };
 136
 137
 138 struct hwsim_radiotap_hdr {
 139         struct ieee80211_radiotap_header hdr;
 140         u8 rt_flags;
 141         u8 rt_rate;
 142         __le16 rt_channel;
 143         __le16 rt_chbitmask;
 144 } __attribute__ ((packed));
 145
 146
 147 static int hwsim_mon_xmit(struct sk_buff *skb, struct net_device *dev)
 148 {
 149         /* TODO: allow packet injection */
 150         dev_kfree_skb(skb);
 151         return 0;
 152 }
 153
 154
 155 static void mac80211_hwsim_monitor_rx(struct ieee80211_hw *hw,
 156                                       struct sk_buff *tx_skb)
 157 {
 158         struct mac80211_hwsim_data *data = hw->priv;
 159         struct sk_buff *skb;
 160         struct hwsim_radiotap_hdr *hdr;
 161         u16 flags;
 162         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx_skb);
 163         struct ieee80211_rate *txrate = ieee80211_get_tx_rate(hw, info);
 164
 165         if (!netif_running(hwsim_mon))
 166                 return;
 167
 168         skb = skb_copy_expand(tx_skb, sizeof(*hdr), 0, GFP_ATOMIC);
 169         if (skb == NULL)
 170                 return;
 171
 172         hdr = (struct hwsim_radiotap_hdr *) skb_push(skb, sizeof(*hdr));
 173         hdr->hdr.it_version = PKTHDR_RADIOTAP_VERSION;
 174         hdr->hdr.it_pad = 0;
 175         hdr->hdr.it_len = cpu_to_le16(sizeof(*hdr));
 176         hdr->hdr.it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 177                                           (1 << IEEE80211_RADIOTAP_RATE) |
 178                                           (1 << IEEE80211_RADIOTAP_CHANNEL));
 179         hdr->rt_flags = 0;
 180         hdr->rt_rate = txrate->bitrate / 5;
 181         hdr->rt_channel = cpu_to_le16(data->channel->center_freq);
 182         flags = IEEE80211_CHAN_2GHZ;
 183         if (txrate->flags & IEEE80211_RATE_ERP_G)
 184                 flags |= IEEE80211_CHAN_OFDM;
 185         else
 186                 flags |= IEEE80211_CHAN_CCK;
 187         hdr->rt_chbitmask = cpu_to_le16(flags);
 188
 189         skb->dev = hwsim_mon;
 190         skb_set_mac_header(skb, 0);
 191         skb->ip_summed = CHECKSUM_UNNECESSARY;
 192         skb->pkt_type = PACKET_OTHERHOST;
 193         skb->protocol = htons(ETH_P_802_2);
 194         memset(skb->cb, 0, sizeof(skb->cb));
 195         netif_rx(skb);
 196 }
 197
 198
 199 static bool mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
 200                                     struct sk_buff *skb)
 201 {
 202         struct mac80211_hwsim_data *data = hw->priv, *data2;
 203         bool ack = false;
 204         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 205         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 206         struct ieee80211_rx_status rx_status;
 207
 208         memset(&rx_status, 0, sizeof(rx_status));
 209         /* TODO: set mactime */
 210         rx_status.freq = data->channel->center_freq;
 211         rx_status.band = data->channel->band;
 212         rx_status.rate_idx = info->tx_rate_idx;
 213         /* TODO: simulate signal strength (and optional packet drop) */
 214
 215         /* Copy skb to all enabled radios that are on the current frequency */
 216         spin_lock(&hwsim_radio_lock);
 217         list_for_each_entry(data2, &hwsim_radios, list) {
 218                 struct sk_buff *nskb;
 219
 220                 if (data == data2)
 221                         continue;
 222
 223                 if (!data2->started || !data2->radio_enabled ||
 224                     data->channel->center_freq != data2->channel->center_freq)
 225                         continue;
 226
 227                 nskb = skb_copy(skb, GFP_ATOMIC);
 228                 if (nskb == NULL)
 229                         continue;
 230
 231                 if (memcmp(hdr->addr1, data2->hw->wiphy->perm_addr,
 232                            ETH_ALEN) == 0)
 233                         ack = true;
 234                 ieee80211_rx_irqsafe(data2->hw, nskb, &rx_status);
 235         }
 236         spin_unlock(&hwsim_radio_lock);
 237
 238         return ack;
 239 }
 240
 241
 242 static int mac80211_hwsim_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 243 {
 244         struct mac80211_hwsim_data *data = hw->priv;
 245         bool ack;
 246         struct ieee80211_tx_info *txi;
 247
 248         mac80211_hwsim_monitor_rx(hw, skb);
 249
 250         if (skb->len < 10) {
 251                 /* Should not happen; just a sanity check for addr1 use */
 252                 dev_kfree_skb(skb);
 253                 return NETDEV_TX_OK;
 254         }
 255
 256         if (!data->radio_enabled) {
 257                 printk(KERN_DEBUG "%s: dropped TX frame since radio "
 258                        "disabled\n", wiphy_name(hw->wiphy));
 259                 dev_kfree_skb(skb);
 260                 return NETDEV_TX_OK;
 261         }
 262
 263         ack = mac80211_hwsim_tx_frame(hw, skb);
 264
 265         txi = IEEE80211_SKB_CB(skb);
 266
 267         if (txi->control.vif)
 268                 hwsim_check_magic(txi->control.vif);
 269         if (txi->control.sta)
 270                 hwsim_check_sta_magic(txi->control.sta);
 271
 272         memset(&txi->status, 0, sizeof(txi->status));
 273         if (!(txi->flags & IEEE80211_TX_CTL_NO_ACK)) {
 274                 if (ack)
 275                         txi->flags |= IEEE80211_TX_STAT_ACK;
 276                 else
 277                         txi->status.excessive_retries = 1;
 278         }
 279         ieee80211_tx_status_irqsafe(hw, skb);
 280         return NETDEV_TX_OK;
 281 }
 282
 283
 284 static int mac80211_hwsim_start(struct ieee80211_hw *hw)
 285 {
 286         struct mac80211_hwsim_data *data = hw->priv;
 287         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 288         data->started = 1;
 289         return 0;
 290 }
 291
 292
 293 static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
 294 {
 295         struct mac80211_hwsim_data *data = hw->priv;
 296         data->started = 0;
 297         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 298 }
 299
 300
 301 static int mac80211_hwsim_add_interface(struct ieee80211_hw *hw,
 302                                         struct ieee80211_if_init_conf *conf)
 303 {
 304         DECLARE_MAC_BUF(mac);
 305         printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 306                wiphy_name(hw->wiphy), __func__, conf->type,
 307                print_mac(mac, conf->mac_addr));
 308         hwsim_set_magic(conf->vif);
 309         return 0;
 310 }
 311
 312
 313 static void mac80211_hwsim_remove_interface(
 314         struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf)
 315 {
 316         DECLARE_MAC_BUF(mac);
 317         printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
 318                wiphy_name(hw->wiphy), __func__, conf->type,
 319                print_mac(mac, conf->mac_addr));
 320         hwsim_check_magic(conf->vif);
 321         hwsim_clear_magic(conf->vif);
 322 }
 323
 324
 325 static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
 326                                      struct ieee80211_vif *vif)
 327 {
 328         struct ieee80211_hw *hw = arg;
 329         struct sk_buff *skb;
 330         struct ieee80211_tx_info *info;
 331
 332         hwsim_check_magic(vif);
 333
 334         if (vif->type != NL80211_IFTYPE_AP)
 335                 return;
 336
 337         skb = ieee80211_beacon_get(hw, vif);
 338         if (skb == NULL)
 339                 return;
 340         info = IEEE80211_SKB_CB(skb);
 341
 342         mac80211_hwsim_monitor_rx(hw, skb);
 343         mac80211_hwsim_tx_frame(hw, skb);
 344         dev_kfree_skb(skb);
 345 }
 346
 347
 348 static void mac80211_hwsim_beacon(unsigned long arg)
 349 {
 350         struct ieee80211_hw *hw = (struct ieee80211_hw *) arg;
 351         struct mac80211_hwsim_data *data = hw->priv;
 352
 353         if (!data->started || !data->radio_enabled)
 354                 return;
 355
 356         ieee80211_iterate_active_interfaces_atomic(
 357                 hw, mac80211_hwsim_beacon_tx, hw);
 358
 359         data->beacon_timer.expires = jiffies + data->beacon_int;
 360         add_timer(&data->beacon_timer);
 361 }
 362
 363
 364 static int mac80211_hwsim_config(struct ieee80211_hw *hw,
 365                                  struct ieee80211_conf *conf)
 366 {
 367         struct mac80211_hwsim_data *data = hw->priv;
 368
 369         printk(KERN_DEBUG "%s:%s (freq=%d radio_enabled=%d beacon_int=%d)\n",
 370                wiphy_name(hw->wiphy), __func__,
 371                conf->channel->center_freq, conf->radio_enabled,
 372                conf->beacon_int);
 373
 374         data->channel = conf->channel;
 375         data->radio_enabled = conf->radio_enabled;
 376         data->beacon_int = 1024 * conf->beacon_int / 1000 * HZ / 1000;
 377         if (data->beacon_int < 1)
 378                 data->beacon_int = 1;
 379
 380         if (!data->started || !data->radio_enabled)
 381                 del_timer(&data->beacon_timer);
 382         else
 383                 mod_timer(&data->beacon_timer, jiffies + data->beacon_int);
 384
 385         return 0;
 386 }
 387
 388
 389 static void mac80211_hwsim_configure_filter(struct ieee80211_hw *hw,
 390                                             unsigned int changed_flags,
 391                                             unsigned int *total_flags,
 392                                             int mc_count,
 393                                             struct dev_addr_list *mc_list)
 394 {
 395         struct mac80211_hwsim_data *data = hw->priv;
 396
 397         printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
 398
 399         data->rx_filter = 0;
 400         if (*total_flags & FIF_PROMISC_IN_BSS)
 401                 data->rx_filter |= FIF_PROMISC_IN_BSS;
 402         if (*total_flags & FIF_ALLMULTI)
 403                 data->rx_filter |= FIF_ALLMULTI;
 404
 405         *total_flags = data->rx_filter;
 406 }
 407
 408 static int mac80211_hwsim_config_interface(struct ieee80211_hw *hw,
 409                                            struct ieee80211_vif *vif,
 410                                            struct ieee80211_if_conf *conf)
 411 {
 412         hwsim_check_magic(vif);
 413         return 0;
 414 }
 415
 416 static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw,
 417                                             struct ieee80211_vif *vif,
 418                                             struct ieee80211_bss_conf *info,
 419                                             u32 changed)
 420 {
 421         hwsim_check_magic(vif);
 422 }
 423
 424 static void mac80211_hwsim_sta_notify(struct ieee80211_hw *hw,
 425                                       struct ieee80211_vif *vif,
 426                                       enum sta_notify_cmd cmd,
 427                                       struct ieee80211_sta *sta)
 428 {
 429         hwsim_check_magic(vif);
 430         switch (cmd) {
 431         case STA_NOTIFY_ADD:
 432                 hwsim_set_sta_magic(sta);
 433                 break;
 434         case STA_NOTIFY_REMOVE:
 435                 hwsim_clear_sta_magic(sta);
 436                 break;
 437         }
 438 }
 439
 440 static int mac80211_hwsim_set_tim(struct ieee80211_hw *hw,
 441                                   struct ieee80211_sta *sta,
 442                                   bool set)
 443 {
 444         hwsim_check_sta_magic(sta);
 445         return 0;
 446 }
 447
 448 static const struct ieee80211_ops mac80211_hwsim_ops =
 449 {
 450         .tx = mac80211_hwsim_tx,
 451         .start = mac80211_hwsim_start,
 452         .stop = mac80211_hwsim_stop,
 453         .add_interface = mac80211_hwsim_add_interface,
 454         .remove_interface = mac80211_hwsim_remove_interface,
 455         .config = mac80211_hwsim_config,
 456         .configure_filter = mac80211_hwsim_configure_filter,
 457         .config_interface = mac80211_hwsim_config_interface,
 458         .bss_info_changed = mac80211_hwsim_bss_info_changed,
 459         .sta_notify = mac80211_hwsim_sta_notify,
 460         .set_tim = mac80211_hwsim_set_tim,
 461 };
 462
 463
 464 static void mac80211_hwsim_free(void)
 465 {
 466         struct list_head tmplist, *i, *tmp;
 467         struct mac80211_hwsim_data *data;
 468
 469         INIT_LIST_HEAD(&tmplist);
 470
 471         spin_lock_bh(&hwsim_radio_lock);
 472         list_for_each_safe(i, tmp, &hwsim_radios)
 473                 list_move(i, &tmplist);
 474         spin_unlock_bh(&hwsim_radio_lock);
 475
 476         list_for_each_entry(data, &tmplist, list) {
 477                 ieee80211_unregister_hw(data->hw);
 478                 device_unregister(data->dev);
 479                 ieee80211_free_hw(data->hw);
 480         }
 481         class_destroy(hwsim_class);
 482 }
 483
 484
 485 static struct device_driver mac80211_hwsim_driver = {
 486         .name = "mac80211_hwsim"
 487 };
 488
 489
 490 static void hwsim_mon_setup(struct net_device *dev)
 491 {
 492         dev->hard_start_xmit = hwsim_mon_xmit;
 493         dev->destructor = free_netdev;
 494         ether_setup(dev);
 495         dev->tx_queue_len = 0;
 496         dev->type = ARPHRD_IEEE80211_RADIOTAP;
 497         memset(dev->dev_addr, 0, ETH_ALEN);
 498         dev->dev_addr[0] = 0x12;
 499 }
 500
 501
 502 static int __init init_mac80211_hwsim(void)
 503 {
 504         int i, err = 0;
 505         u8 addr[ETH_ALEN];
 506         struct mac80211_hwsim_data *data;
 507         struct ieee80211_hw *hw;
 508         DECLARE_MAC_BUF(mac);
 509
 510         if (radios < 1 || radios > 100)
 511                 return -EINVAL;
 512
 513         spin_lock_init(&hwsim_radio_lock);
 514         INIT_LIST_HEAD(&hwsim_radios);
 515
 516         hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim");
 517         if (IS_ERR(hwsim_class))
 518                 return PTR_ERR(hwsim_class);
 519
 520         memset(addr, 0, ETH_ALEN);
 521         addr[0] = 0x02;
 522
 523         for (i = 0; i < radios; i++) {
 524                 printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n",
 525                        i);
 526                 hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops);
 527                 if (!hw) {
 528                         printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw "
 529                                "failed\n");
 530                         err = -ENOMEM;
 531                         goto failed;
 532                 }
 533                 data = hw->priv;
 534                 data->hw = hw;
 535
 536                 data->dev = device_create_drvdata(hwsim_class, NULL, 0, hw,
 537                                                 "hwsim%d", i);
 538                 if (IS_ERR(data->dev)) {
 539                         printk(KERN_DEBUG
 540                                "mac80211_hwsim: device_create_drvdata "
 541                                "failed (%ld)\n", PTR_ERR(data->dev));
 542                         err = -ENOMEM;
 543                         goto failed_drvdata;
 544                 }
 545                 data->dev->driver = &mac80211_hwsim_driver;
 546
 547                 SET_IEEE80211_DEV(hw, data->dev);
 548                 addr[3] = i >> 8;
 549                 addr[4] = i;
 550                 SET_IEEE80211_PERM_ADDR(hw, addr);
 551
 552                 hw->channel_change_time = 1;
 553                 hw->queues = 4;
 554                 hw->wiphy->interface_modes =
 555                         BIT(NL80211_IFTYPE_STATION) |
 556                         BIT(NL80211_IFTYPE_AP);
 557                 hw->ampdu_queues = 1;
 558
 559                 /* ask mac80211 to reserve space for magic */
 560                 hw->vif_data_size = sizeof(struct hwsim_vif_priv);
 561                 hw->sta_data_size = sizeof(struct hwsim_sta_priv);
 562
 563                 memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));
 564                 memcpy(data->rates, hwsim_rates, sizeof(hwsim_rates));
 565                 data->band.channels = data->channels;
 566                 data->band.n_channels = ARRAY_SIZE(hwsim_channels);
 567                 data->band.bitrates = data->rates;
 568                 data->band.n_bitrates = ARRAY_SIZE(hwsim_rates);
 569                 data->band.ht_info.ht_supported = 1;
 570                 data->band.ht_info.cap = IEEE80211_HT_CAP_SUP_WIDTH |
 571                         IEEE80211_HT_CAP_GRN_FLD |
 572                         IEEE80211_HT_CAP_SGI_40 |
 573                         IEEE80211_HT_CAP_DSSSCCK40;
 574                 data->band.ht_info.ampdu_factor = 0x3;
 575                 data->band.ht_info.ampdu_density = 0x6;
 576                 memset(data->band.ht_info.supp_mcs_set, 0,
 577                        sizeof(data->band.ht_info.supp_mcs_set));
 578                 data->band.ht_info.supp_mcs_set[0] = 0xff;
 579                 data->band.ht_info.supp_mcs_set[1] = 0xff;
 580                 data->band.ht_info.supp_mcs_set[12] =
 581                         IEEE80211_HT_CAP_MCS_TX_DEFINED;
 582                 hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &data->band;
 583
 584                 err = ieee80211_register_hw(hw);
 585                 if (err < 0) {
 586                         printk(KERN_DEBUG "mac80211_hwsim: "
 587                                "ieee80211_register_hw failed (%d)\n", err);
 588                         goto failed_hw;
 589                 }
 590
 591                 printk(KERN_DEBUG "%s: hwaddr %s registered\n",
 592                        wiphy_name(hw->wiphy),
 593                        print_mac(mac, hw->wiphy->perm_addr));
 594
 595                 setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
 596                             (unsigned long) hw);
 597
 598                 list_add_tail(&data->list, &hwsim_radios);
 599         }
 600
 601         hwsim_mon = alloc_netdev(0, "hwsim%d", hwsim_mon_setup);
 602         if (hwsim_mon == NULL)
 603                 goto failed;
 604
 605         rtnl_lock();
 606
 607         err = dev_alloc_name(hwsim_mon, hwsim_mon->name);
 608         if (err < 0)
 609                 goto failed_mon;
 610
 611
 612         err = register_netdevice(hwsim_mon);
 613         if (err < 0)
 614                 goto failed_mon;
 615
 616         rtnl_unlock();
 617
 618         return 0;
 619
 620 failed_mon:
 621         rtnl_unlock();
 622         free_netdev(hwsim_mon);
 623         mac80211_hwsim_free();
 624         return err;
 625
 626 failed_hw:
 627         device_unregister(data->dev);
 628 failed_drvdata:
 629         ieee80211_free_hw(hw);
 630 failed:
 631         mac80211_hwsim_free();
 632         return err;
 633 }
 634
 635
 636 static void __exit exit_mac80211_hwsim(void)
 637 {
 638         printk(KERN_DEBUG "mac80211_hwsim: unregister radios\n");
 639
 640         unregister_netdev(hwsim_mon);
 641         mac80211_hwsim_free();
 642 }
 643
 644
 645 module_init(init_mac80211_hwsim);
 646 module_exit(exit_mac80211_hwsim);