net/mac80211/work.c

   1 /*
   2  * mac80211 work implementation
   3  *
   4  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
   5  * Copyright 2004, Instant802 Networks, Inc.
   6  * Copyright 2005, Devicescape Software, Inc.
   7  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
   9  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/if_arp.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/crc32.h>
  22 #include <linux/slab.h>
  23 #include <net/mac80211.h>
  24 #include <asm/unaligned.h>
  25
  26 #include "ieee80211_i.h"
  27 #include "rate.h"
  28
  29 #define IEEE80211_AUTH_TIMEOUT (HZ / 5)
  30 #define IEEE80211_AUTH_MAX_TRIES 3
  31 #define IEEE80211_ASSOC_TIMEOUT (HZ / 5)
  32 #define IEEE80211_ASSOC_MAX_TRIES 3
  33
  34 enum work_action {
  35         WORK_ACT_MISMATCH,
  36         WORK_ACT_NONE,
  37         WORK_ACT_TIMEOUT,
  38         WORK_ACT_DONE,
  39 };
  40
  41
  42 /* utils */
  43 static inline void ASSERT_WORK_MTX(struct ieee80211_local *local)
  44 {
  45         lockdep_assert_held(&local->mtx);
  46 }
  47
  48 /*
  49  * We can have multiple work items (and connection probing)
  50  * scheduling this timer, but we need to take care to only
  51  * reschedule it when it should fire _earlier_ than it was
  52  * asked for before, or if it's not pending right now. This
  53  * function ensures that. Note that it then is required to
  54  * run this function for all timeouts after the first one
  55  * has happened -- the work that runs from this timer will
  56  * do that.
  57  */
  58 static void run_again(struct ieee80211_local *local,
  59                       unsigned long timeout)
  60 {
  61         ASSERT_WORK_MTX(local);
  62
  63         if (!timer_pending(&local->work_timer) ||
  64             time_before(timeout, local->work_timer.expires))
  65                 mod_timer(&local->work_timer, timeout);
  66 }
  67
  68 void free_work(struct ieee80211_work *wk)
  69 {
  70         kfree_rcu(wk, rcu_head);
  71 }
  72
  73 static int ieee80211_compatible_rates(const u8 *supp_rates, int supp_rates_len,
  74                                       struct ieee80211_supported_band *sband,
  75                                       u32 *rates)
  76 {
  77         int i, j, count;
  78         *rates = 0;
  79         count = 0;
  80         for (i = 0; i < supp_rates_len; i++) {
  81                 int rate = (supp_rates[i] & 0x7F) * 5;
  82
  83                 for (j = 0; j < sband->n_bitrates; j++)
  84                         if (sband->bitrates[j].bitrate == rate) {
  85                                 *rates |= BIT(j);
  86                                 count++;
  87                                 break;
  88                         }
  89         }
  90
  91         return count;
  92 }
  93
  94 /* frame sending functions */
  95
  96 static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
  97                                 struct ieee80211_supported_band *sband,
  98                                 struct ieee80211_channel *channel,
  99                                 enum ieee80211_smps_mode smps)
 100 {
 101         struct ieee80211_ht_info *ht_info;
 102         u8 *pos;
 103         u32 flags = channel->flags;
 104         u16 cap = sband->ht_cap.cap;
 105         __le16 tmp;
 106
 107         if (!sband->ht_cap.ht_supported)
 108                 return;
 109
 110         if (!ht_info_ie)
 111                 return;
 112
 113         if (ht_info_ie[1] < sizeof(struct ieee80211_ht_info))
 114                 return;
 115
 116         ht_info = (struct ieee80211_ht_info *)(ht_info_ie + 2);
 117
 118         /* determine capability flags */
 119
 120         switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
 121         case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
 122                 if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
 123                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 124                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 125                 }
 126                 break;
 127         case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
 128                 if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
 129                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
 130                         cap &= ~IEEE80211_HT_CAP_SGI_40;
 131                 }
 132                 break;
 133         }
 134
 135         /* set SM PS mode properly */
 136         cap &= ~IEEE80211_HT_CAP_SM_PS;
 137         switch (smps) {
 138         case IEEE80211_SMPS_AUTOMATIC:
 139         case IEEE80211_SMPS_NUM_MODES:
 140                 WARN_ON(1);
 141         case IEEE80211_SMPS_OFF:
 142                 cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
 143                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 144                 break;
 145         case IEEE80211_SMPS_STATIC:
 146                 cap |= WLAN_HT_CAP_SM_PS_STATIC <<
 147                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 148                 break;
 149         case IEEE80211_SMPS_DYNAMIC:
 150                 cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
 151                         IEEE80211_HT_CAP_SM_PS_SHIFT;
 152                 break;
 153         }
 154
 155         /* reserve and fill IE */
 156
 157         pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 158         *pos++ = WLAN_EID_HT_CAPABILITY;
 159         *pos++ = sizeof(struct ieee80211_ht_cap);
 160         memset(pos, 0, sizeof(struct ieee80211_ht_cap));
 161
 162         /* capability flags */
 163         tmp = cpu_to_le16(cap);
 164         memcpy(pos, &tmp, sizeof(u16));
 165         pos += sizeof(u16);
 166
 167         /* AMPDU parameters */
 168         *pos++ = sband->ht_cap.ampdu_factor |
 169                  (sband->ht_cap.ampdu_density <<
 170                         IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
 171
 172         /* MCS set */
 173         memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
 174         pos += sizeof(sband->ht_cap.mcs);
 175
 176         /* extended capabilities */
 177         pos += sizeof(__le16);
 178
 179         /* BF capabilities */
 180         pos += sizeof(__le32);
 181
 182         /* antenna selection */
 183         pos += sizeof(u8);
 184 }
 185
 186 static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 187                                  struct ieee80211_work *wk)
 188 {
 189         struct ieee80211_local *local = sdata->local;
 190         struct sk_buff *skb;
 191         struct ieee80211_mgmt *mgmt;
 192         u8 *pos, qos_info;
 193         size_t offset = 0, noffset;
 194         int i, count, rates_len, supp_rates_len;
 195         u16 capab;
 196         struct ieee80211_supported_band *sband;
 197         u32 rates = 0;
 198
 199         sband = local->hw.wiphy->bands[wk->chan->band];
 200
 201         if (wk->assoc.supp_rates_len) {
 202                 /*
 203                  * Get all rates supported by the device and the AP as
 204                  * some APs don't like getting a superset of their rates
 205                  * in the association request (e.g. D-Link DAP 1353 in
 206                  * b-only mode)...
 207                  */
 208                 rates_len = ieee80211_compatible_rates(wk->assoc.supp_rates,
 209                                                        wk->assoc.supp_rates_len,
 210                                                        sband, &rates);
 211         } else {
 212                 /*
 213                  * In case AP not provide any supported rates information
 214                  * before association, we send information element(s) with
 215                  * all rates that we support.
 216                  */
 217                 rates = ~0;
 218                 rates_len = sband->n_bitrates;
 219         }
 220
 221         skb = alloc_skb(local->hw.extra_tx_headroom +
 222                         sizeof(*mgmt) + /* bit too much but doesn't matter */
 223                         2 + wk->assoc.ssid_len + /* SSID */
 224                         4 + rates_len + /* (extended) rates */
 225                         4 + /* power capability */
 226                         2 + 2 * sband->n_channels + /* supported channels */
 227                         2 + sizeof(struct ieee80211_ht_cap) + /* HT */
 228                         wk->ie_len + /* extra IEs */
 229                         9, /* WMM */
 230                         GFP_KERNEL);
 231         if (!skb) {
 232                 printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 233                        "frame\n", sdata->name);
 234                 return;
 235         }
 236         skb_reserve(skb, local->hw.extra_tx_headroom);
 237
 238         capab = WLAN_CAPABILITY_ESS;
 239
 240         if (sband->band == IEEE80211_BAND_2GHZ) {
 241                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
 242                         capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
 243                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
 244                         capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 245         }
 246
 247         if (wk->assoc.capability & WLAN_CAPABILITY_PRIVACY)
 248                 capab |= WLAN_CAPABILITY_PRIVACY;
 249
 250         if ((wk->assoc.capability & WLAN_CAPABILITY_SPECTRUM_MGMT) &&
 251             (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT))
 252                 capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;
 253
 254         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 255         memset(mgmt, 0, 24);
 256         memcpy(mgmt->da, wk->filter_ta, ETH_ALEN);
 257         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 258         memcpy(mgmt->bssid, wk->filter_ta, ETH_ALEN);
 259
 260         if (!is_zero_ether_addr(wk->assoc.prev_bssid)) {
 261                 skb_put(skb, 10);
 262                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 263                                                   IEEE80211_STYPE_REASSOC_REQ);
 264                 mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
 265                 mgmt->u.reassoc_req.listen_interval =
 266                                 cpu_to_le16(local->hw.conf.listen_interval);
 267                 memcpy(mgmt->u.reassoc_req.current_ap, wk->assoc.prev_bssid,
 268                        ETH_ALEN);
 269         } else {
 270                 skb_put(skb, 4);
 271                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 272                                                   IEEE80211_STYPE_ASSOC_REQ);
 273                 mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
 274                 mgmt->u.assoc_req.listen_interval =
 275                                 cpu_to_le16(local->hw.conf.listen_interval);
 276         }
 277
 278         /* SSID */
 279         pos = skb_put(skb, 2 + wk->assoc.ssid_len);
 280         *pos++ = WLAN_EID_SSID;
 281         *pos++ = wk->assoc.ssid_len;
 282         memcpy(pos, wk->assoc.ssid, wk->assoc.ssid_len);
 283
 284         /* add all rates which were marked to be used above */
 285         supp_rates_len = rates_len;
 286         if (supp_rates_len > 8)
 287                 supp_rates_len = 8;
 288
 289         pos = skb_put(skb, supp_rates_len + 2);
 290         *pos++ = WLAN_EID_SUPP_RATES;
 291         *pos++ = supp_rates_len;
 292
 293         count = 0;
 294         for (i = 0; i < sband->n_bitrates; i++) {
 295                 if (BIT(i) & rates) {
 296                         int rate = sband->bitrates[i].bitrate;
 297                         *pos++ = (u8) (rate / 5);
 298                         if (++count == 8)
 299                                 break;
 300                 }
 301         }
 302
 303         if (rates_len > count) {
 304                 pos = skb_put(skb, rates_len - count + 2);
 305                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
 306                 *pos++ = rates_len - count;
 307
 308                 for (i++; i < sband->n_bitrates; i++) {
 309                         if (BIT(i) & rates) {
 310                                 int rate = sband->bitrates[i].bitrate;
 311                                 *pos++ = (u8) (rate / 5);
 312                         }
 313                 }
 314         }
 315
 316         if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT) {
 317                 /* 1. power capabilities */
 318                 pos = skb_put(skb, 4);
 319                 *pos++ = WLAN_EID_PWR_CAPABILITY;
 320                 *pos++ = 2;
 321                 *pos++ = 0; /* min tx power */
 322                 *pos++ = wk->chan->max_power; /* max tx power */
 323
 324                 /* 2. supported channels */
 325                 /* TODO: get this in reg domain format */
 326                 pos = skb_put(skb, 2 * sband->n_channels + 2);
 327                 *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 328                 *pos++ = 2 * sband->n_channels;
 329                 for (i = 0; i < sband->n_channels; i++) {
 330                         *pos++ = ieee80211_frequency_to_channel(
 331                                         sband->channels[i].center_freq);
 332                         *pos++ = 1; /* one channel in the subband*/
 333                 }
 334         }
 335
 336         /* if present, add any custom IEs that go before HT */
 337         if (wk->ie_len && wk->ie) {
 338                 static const u8 before_ht[] = {
 339                         WLAN_EID_SSID,
 340                         WLAN_EID_SUPP_RATES,
 341                         WLAN_EID_EXT_SUPP_RATES,
 342                         WLAN_EID_PWR_CAPABILITY,
 343                         WLAN_EID_SUPPORTED_CHANNELS,
 344                         WLAN_EID_RSN,
 345                         WLAN_EID_QOS_CAPA,
 346                         WLAN_EID_RRM_ENABLED_CAPABILITIES,
 347                         WLAN_EID_MOBILITY_DOMAIN,
 348                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 349                 };
 350                 noffset = ieee80211_ie_split(wk->ie, wk->ie_len,
 351                                              before_ht, ARRAY_SIZE(before_ht),
 352                                              offset);
 353                 pos = skb_put(skb, noffset - offset);
 354                 memcpy(pos, wk->ie + offset, noffset - offset);
 355                 offset = noffset;
 356         }
 357
 358         if (wk->assoc.use_11n && wk->assoc.wmm_used &&
 359             local->hw.queues >= 4)
 360                 ieee80211_add_ht_ie(skb, wk->assoc.ht_information_ie,
 361                                     sband, wk->chan, wk->assoc.smps);
 362
 363         /* if present, add any custom non-vendor IEs that go after HT */
 364         if (wk->ie_len && wk->ie) {
 365                 noffset = ieee80211_ie_split_vendor(wk->ie, wk->ie_len,
 366                                                     offset);
 367                 pos = skb_put(skb, noffset - offset);
 368                 memcpy(pos, wk->ie + offset, noffset - offset);
 369                 offset = noffset;
 370         }
 371
 372         if (wk->assoc.wmm_used && local->hw.queues >= 4) {
 373                 if (wk->assoc.uapsd_used) {
 374                         qos_info = local->uapsd_queues;
 375                         qos_info |= (local->uapsd_max_sp_len <<
 376                                      IEEE80211_WMM_IE_STA_QOSINFO_SP_SHIFT);
 377                 } else {
 378                         qos_info = 0;
 379                 }
 380
 381                 pos = skb_put(skb, 9);
 382                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 383                 *pos++ = 7; /* len */
 384                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
 385                 *pos++ = 0x50;
 386                 *pos++ = 0xf2;
 387                 *pos++ = 2; /* WME */
 388                 *pos++ = 0; /* WME info */
 389                 *pos++ = 1; /* WME ver */
 390                 *pos++ = qos_info;
 391         }
 392
 393         /* add any remaining custom (i.e. vendor specific here) IEs */
 394         if (wk->ie_len && wk->ie) {
 395                 noffset = wk->ie_len;
 396                 pos = skb_put(skb, noffset - offset);
 397                 memcpy(pos, wk->ie + offset, noffset - offset);
 398         }
 399
 400         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 401         ieee80211_tx_skb(sdata, skb);
 402 }
 403
 404 static void ieee80211_remove_auth_bss(struct ieee80211_local *local,
 405                                       struct ieee80211_work *wk)
 406 {
 407         struct cfg80211_bss *cbss;
 408         u16 capa_val = WLAN_CAPABILITY_ESS;
 409
 410         if (wk->probe_auth.privacy)
 411                 capa_val |= WLAN_CAPABILITY_PRIVACY;
 412
 413         cbss = cfg80211_get_bss(local->hw.wiphy, wk->chan, wk->filter_ta,
 414                                 wk->probe_auth.ssid, wk->probe_auth.ssid_len,
 415                                 WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_PRIVACY,
 416                                 capa_val);
 417         if (!cbss)
 418                 return;
 419
 420         cfg80211_unlink_bss(local->hw.wiphy, cbss);
 421         cfg80211_put_bss(cbss);
 422 }
 423
 424 static enum work_action __must_check
 425 ieee80211_direct_probe(struct ieee80211_work *wk)
 426 {
 427         struct ieee80211_sub_if_data *sdata = wk->sdata;
 428         struct ieee80211_local *local = sdata->local;
 429
 430         wk->probe_auth.tries++;
 431         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 432                 printk(KERN_DEBUG "%s: direct probe to %pM timed out\n",
 433                        sdata->name, wk->filter_ta);
 434
 435                 /*
 436                  * Most likely AP is not in the range so remove the
 437                  * bss struct for that AP.
 438                  */
 439                 ieee80211_remove_auth_bss(local, wk);
 440
 441                 return WORK_ACT_TIMEOUT;
 442         }
 443
 444         printk(KERN_DEBUG "%s: direct probe to %pM (try %d/%i)\n",
 445                sdata->name, wk->filter_ta, wk->probe_auth.tries,
 446                IEEE80211_AUTH_MAX_TRIES);
 447
 448         /*
 449          * Direct probe is sent to broadcast address as some APs
 450          * will not answer to direct packet in unassociated state.
 451          */
 452         ieee80211_send_probe_req(sdata, NULL, wk->probe_auth.ssid,
 453                                  wk->probe_auth.ssid_len, NULL, 0);
 454
 455         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 456         run_again(local, wk->timeout);
 457
 458         return WORK_ACT_NONE;
 459 }
 460
 461
 462 static enum work_action __must_check
 463 ieee80211_authenticate(struct ieee80211_work *wk)
 464 {
 465         struct ieee80211_sub_if_data *sdata = wk->sdata;
 466         struct ieee80211_local *local = sdata->local;
 467
 468         wk->probe_auth.tries++;
 469         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
 470                 printk(KERN_DEBUG "%s: authentication with %pM"
 471                        " timed out\n", sdata->name, wk->filter_ta);
 472
 473                 /*
 474                  * Most likely AP is not in the range so remove the
 475                  * bss struct for that AP.
 476                  */
 477                 ieee80211_remove_auth_bss(local, wk);
 478
 479                 return WORK_ACT_TIMEOUT;
 480         }
 481
 482         printk(KERN_DEBUG "%s: authenticate with %pM (try %d)\n",
 483                sdata->name, wk->filter_ta, wk->probe_auth.tries);
 484
 485         ieee80211_send_auth(sdata, 1, wk->probe_auth.algorithm, wk->ie,
 486                             wk->ie_len, wk->filter_ta, NULL, 0, 0);
 487         wk->probe_auth.transaction = 2;
 488
 489         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
 490         run_again(local, wk->timeout);
 491
 492         return WORK_ACT_NONE;
 493 }
 494
 495 static enum work_action __must_check
 496 ieee80211_associate(struct ieee80211_work *wk)
 497 {
 498         struct ieee80211_sub_if_data *sdata = wk->sdata;
 499         struct ieee80211_local *local = sdata->local;
 500
 501         wk->assoc.tries++;
 502         if (wk->assoc.tries > IEEE80211_ASSOC_MAX_TRIES) {
 503                 printk(KERN_DEBUG "%s: association with %pM"
 504                        " timed out\n",
 505                        sdata->name, wk->filter_ta);
 506
 507                 /*
 508                  * Most likely AP is not in the range so remove the
 509                  * bss struct for that AP.
 510                  */
 511                 if (wk->assoc.bss)
 512                         cfg80211_unlink_bss(local->hw.wiphy, wk->assoc.bss);
 513
 514                 return WORK_ACT_TIMEOUT;
 515         }
 516
 517         printk(KERN_DEBUG "%s: associate with %pM (try %d)\n",
 518                sdata->name, wk->filter_ta, wk->assoc.tries);
 519         ieee80211_send_assoc(sdata, wk);
 520
 521         wk->timeout = jiffies + IEEE80211_ASSOC_TIMEOUT;
 522         run_again(local, wk->timeout);
 523
 524         return WORK_ACT_NONE;
 525 }
 526
 527 static enum work_action __must_check
 528 ieee80211_remain_on_channel_timeout(struct ieee80211_work *wk)
 529 {
 530         /*
 531          * First time we run, do nothing -- the generic code will
 532          * have switched to the right channel etc.
 533          */
 534         if (!wk->started) {
 535                 wk->timeout = jiffies + msecs_to_jiffies(wk->remain.duration);
 536
 537                 cfg80211_ready_on_channel(wk->sdata->dev, (unsigned long) wk,
 538                                           wk->chan, wk->chan_type,
 539                                           wk->remain.duration, GFP_KERNEL);
 540
 541                 return WORK_ACT_NONE;
 542         }
 543
 544         return WORK_ACT_TIMEOUT;
 545 }
 546
 547 static enum work_action __must_check
 548 ieee80211_offchannel_tx(struct ieee80211_work *wk)
 549 {
 550         if (!wk->started) {
 551                 wk->timeout = jiffies + msecs_to_jiffies(wk->offchan_tx.wait);
 552
 553                 /*
 554                  * After this, offchan_tx.frame remains but now is no
 555                  * longer a valid pointer -- we still need it as the
 556                  * cookie for canceling this work.
 557                  */
 558                 ieee80211_tx_skb(wk->sdata, wk->offchan_tx.frame);
 559
 560                 return WORK_ACT_NONE;
 561         }
 562
 563         return WORK_ACT_TIMEOUT;
 564 }
 565
 566 static enum work_action __must_check
 567 ieee80211_assoc_beacon_wait(struct ieee80211_work *wk)
 568 {
 569         if (wk->started)
 570                 return WORK_ACT_TIMEOUT;
 571
 572         /*
 573          * Wait up to one beacon interval ...
 574          * should this be more if we miss one?
 575          */
 576         printk(KERN_DEBUG "%s: waiting for beacon from %pM\n",
 577                wk->sdata->name, wk->filter_ta);
 578         wk->timeout = TU_TO_EXP_TIME(wk->assoc.bss->beacon_interval);
 579         return WORK_ACT_NONE;
 580 }
 581
 582 static void ieee80211_auth_challenge(struct ieee80211_work *wk,
 583                                      struct ieee80211_mgmt *mgmt,
 584                                      size_t len)
 585 {
 586         struct ieee80211_sub_if_data *sdata = wk->sdata;
 587         u8 *pos;
 588         struct ieee802_11_elems elems;
 589
 590         pos = mgmt->u.auth.variable;
 591         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 592         if (!elems.challenge)
 593                 return;
 594         ieee80211_send_auth(sdata, 3, wk->probe_auth.algorithm,
 595                             elems.challenge - 2, elems.challenge_len + 2,
 596                             wk->filter_ta, wk->probe_auth.key,
 597                             wk->probe_auth.key_len, wk->probe_auth.key_idx);
 598         wk->probe_auth.transaction = 4;
 599 }
 600
 601 static enum work_action __must_check
 602 ieee80211_rx_mgmt_auth(struct ieee80211_work *wk,
 603                        struct ieee80211_mgmt *mgmt, size_t len)
 604 {
 605         u16 auth_alg, auth_transaction, status_code;
 606
 607         if (wk->type != IEEE80211_WORK_AUTH)
 608                 return WORK_ACT_MISMATCH;
 609
 610         if (len < 24 + 6)
 611                 return WORK_ACT_NONE;
 612
 613         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
 614         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
 615         status_code = le16_to_cpu(mgmt->u.auth.status_code);
 616
 617         if (auth_alg != wk->probe_auth.algorithm ||
 618             auth_transaction != wk->probe_auth.transaction)
 619                 return WORK_ACT_NONE;
 620
 621         if (status_code != WLAN_STATUS_SUCCESS) {
 622                 printk(KERN_DEBUG "%s: %pM denied authentication (status %d)\n",
 623                        wk->sdata->name, mgmt->sa, status_code);
 624                 return WORK_ACT_DONE;
 625         }
 626
 627         switch (wk->probe_auth.algorithm) {
 628         case WLAN_AUTH_OPEN:
 629         case WLAN_AUTH_LEAP:
 630         case WLAN_AUTH_FT:
 631                 break;
 632         case WLAN_AUTH_SHARED_KEY:
 633                 if (wk->probe_auth.transaction != 4) {
 634                         ieee80211_auth_challenge(wk, mgmt, len);
 635                         /* need another frame */
 636                         return WORK_ACT_NONE;
 637                 }
 638                 break;
 639         default:
 640                 WARN_ON(1);
 641                 return WORK_ACT_NONE;
 642         }
 643
 644         printk(KERN_DEBUG "%s: authenticated\n", wk->sdata->name);
 645         return WORK_ACT_DONE;
 646 }
 647
 648 static enum work_action __must_check
 649 ieee80211_rx_mgmt_assoc_resp(struct ieee80211_work *wk,
 650                              struct ieee80211_mgmt *mgmt, size_t len,
 651                              bool reassoc)
 652 {
 653         struct ieee80211_sub_if_data *sdata = wk->sdata;
 654         struct ieee80211_local *local = sdata->local;
 655         u16 capab_info, status_code, aid;
 656         struct ieee802_11_elems elems;
 657         u8 *pos;
 658
 659         if (wk->type != IEEE80211_WORK_ASSOC)
 660                 return WORK_ACT_MISMATCH;
 661
 662         /*
 663          * AssocResp and ReassocResp have identical structure, so process both
 664          * of them in this function.
 665          */
 666
 667         if (len < 24 + 6)
 668                 return WORK_ACT_NONE;
 669
 670         capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info);
 671         status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
 672         aid = le16_to_cpu(mgmt->u.assoc_resp.aid);
 673
 674         printk(KERN_DEBUG "%s: RX %sssocResp from %pM (capab=0x%x "
 675                "status=%d aid=%d)\n",
 676                sdata->name, reassoc ? "Rea" : "A", mgmt->sa,
 677                capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));
 678
 679         pos = mgmt->u.assoc_resp.variable;
 680         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
 681
 682         if (status_code == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY &&
 683             elems.timeout_int && elems.timeout_int_len == 5 &&
 684             elems.timeout_int[0] == WLAN_TIMEOUT_ASSOC_COMEBACK) {
 685                 u32 tu, ms;
 686                 tu = get_unaligned_le32(elems.timeout_int + 1);
 687                 ms = tu * 1024 / 1000;
 688                 printk(KERN_DEBUG "%s: %pM rejected association temporarily; "
 689                        "comeback duration %u TU (%u ms)\n",
 690                        sdata->name, mgmt->sa, tu, ms);
 691                 wk->timeout = jiffies + msecs_to_jiffies(ms);
 692                 if (ms > IEEE80211_ASSOC_TIMEOUT)
 693                         run_again(local, wk->timeout);
 694                 return WORK_ACT_NONE;
 695         }
 696
 697         if (status_code != WLAN_STATUS_SUCCESS)
 698                 printk(KERN_DEBUG "%s: %pM denied association (code=%d)\n",
 699                        sdata->name, mgmt->sa, status_code);
 700         else
 701                 printk(KERN_DEBUG "%s: associated\n", sdata->name);
 702
 703         return WORK_ACT_DONE;
 704 }
 705
 706 static enum work_action __must_check
 707 ieee80211_rx_mgmt_probe_resp(struct ieee80211_work *wk,
 708                              struct ieee80211_mgmt *mgmt, size_t len,
 709                              struct ieee80211_rx_status *rx_status)
 710 {
 711         struct ieee80211_sub_if_data *sdata = wk->sdata;
 712         struct ieee80211_local *local = sdata->local;
 713         size_t baselen;
 714
 715         ASSERT_WORK_MTX(local);
 716
 717         if (wk->type != IEEE80211_WORK_DIRECT_PROBE)
 718                 return WORK_ACT_MISMATCH;
 719
 720         if (len < 24 + 12)
 721                 return WORK_ACT_NONE;
 722
 723         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
 724         if (baselen > len)
 725                 return WORK_ACT_NONE;
 726
 727         printk(KERN_DEBUG "%s: direct probe responded\n", sdata->name);
 728         return WORK_ACT_DONE;
 729 }
 730
 731 static enum work_action __must_check
 732 ieee80211_rx_mgmt_beacon(struct ieee80211_work *wk,
 733                          struct ieee80211_mgmt *mgmt, size_t len)
 734 {
 735         struct ieee80211_sub_if_data *sdata = wk->sdata;
 736         struct ieee80211_local *local = sdata->local;
 737
 738         ASSERT_WORK_MTX(local);
 739
 740         if (wk->type != IEEE80211_WORK_ASSOC_BEACON_WAIT)
 741                 return WORK_ACT_MISMATCH;
 742
 743         if (len < 24 + 12)
 744                 return WORK_ACT_NONE;
 745
 746         printk(KERN_DEBUG "%s: beacon received\n", sdata->name);
 747         return WORK_ACT_DONE;
 748 }
 749
 750 static void ieee80211_work_rx_queued_mgmt(struct ieee80211_local *local,
 751                                           struct sk_buff *skb)
 752 {
 753         struct ieee80211_rx_status *rx_status;
 754         struct ieee80211_mgmt *mgmt;
 755         struct ieee80211_work *wk;
 756         enum work_action rma = WORK_ACT_NONE;
 757         u16 fc;
 758
 759         rx_status = (struct ieee80211_rx_status *) skb->cb;
 760         mgmt = (struct ieee80211_mgmt *) skb->data;
 761         fc = le16_to_cpu(mgmt->frame_control);
 762
 763         mutex_lock(&local->mtx);
 764
 765         list_for_each_entry(wk, &local->work_list, list) {
 766                 const u8 *bssid = NULL;
 767
 768                 switch (wk->type) {
 769                 case IEEE80211_WORK_DIRECT_PROBE:
 770                 case IEEE80211_WORK_AUTH:
 771                 case IEEE80211_WORK_ASSOC:
 772                 case IEEE80211_WORK_ASSOC_BEACON_WAIT:
 773                         bssid = wk->filter_ta;
 774                         break;
 775                 default:
 776                         continue;
 777                 }
 778
 779                 /*
 780                  * Before queuing, we already verified mgmt->sa,
 781                  * so this is needed just for matching.
 782                  */
 783                 if (compare_ether_addr(bssid, mgmt->bssid))
 784                         continue;
 785
 786                 switch (fc & IEEE80211_FCTL_STYPE) {
 787                 case IEEE80211_STYPE_BEACON:
 788                         rma = ieee80211_rx_mgmt_beacon(wk, mgmt, skb->len);
 789                         break;
 790                 case IEEE80211_STYPE_PROBE_RESP:
 791                         rma = ieee80211_rx_mgmt_probe_resp(wk, mgmt, skb->len,
 792                                                            rx_status);
 793                         break;
 794                 case IEEE80211_STYPE_AUTH:
 795                         rma = ieee80211_rx_mgmt_auth(wk, mgmt, skb->len);
 796                         break;
 797                 case IEEE80211_STYPE_ASSOC_RESP:
 798                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 799                                                            skb->len, false);
 800                         break;
 801                 case IEEE80211_STYPE_REASSOC_RESP:
 802                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
 803                                                            skb->len, true);
 804                         break;
 805                 default:
 806                         WARN_ON(1);
 807                         rma = WORK_ACT_NONE;
 808                 }
 809
 810                 /*
 811                  * We've either received an unexpected frame, or we have
 812                  * multiple work items and need to match the frame to the
 813                  * right one.
 814                  */
 815                 if (rma == WORK_ACT_MISMATCH)
 816                         continue;
 817
 818                 /*
 819                  * We've processed this frame for that work, so it can't
 820                  * belong to another work struct.
 821                  * NB: this is also required for correctness for 'rma'!
 822                  */
 823                 break;
 824         }
 825
 826         switch (rma) {
 827         case WORK_ACT_MISMATCH:
 828                 /* ignore this unmatched frame */
 829                 break;
 830         case WORK_ACT_NONE:
 831                 break;
 832         case WORK_ACT_DONE:
 833                 list_del_rcu(&wk->list);
 834                 break;
 835         default:
 836                 WARN(1, "unexpected: %d", rma);
 837         }
 838
 839         mutex_unlock(&local->mtx);
 840
 841         if (rma != WORK_ACT_DONE)
 842                 goto out;
 843
 844         switch (wk->done(wk, skb)) {
 845         case WORK_DONE_DESTROY:
 846                 free_work(wk);
 847                 break;
 848         case WORK_DONE_REQUEUE:
 849                 synchronize_rcu();
 850                 wk->started = false; /* restart */
 851                 mutex_lock(&local->mtx);
 852                 list_add_tail(&wk->list, &local->work_list);
 853                 mutex_unlock(&local->mtx);
 854         }
 855
 856  out:
 857         kfree_skb(skb);
 858 }
 859
 860 static bool ieee80211_work_ct_coexists(enum nl80211_channel_type wk_ct,
 861                                        enum nl80211_channel_type oper_ct)
 862 {
 863         switch (wk_ct) {
 864         case NL80211_CHAN_NO_HT:
 865                 return true;
 866         case NL80211_CHAN_HT20:
 867                 if (oper_ct != NL80211_CHAN_NO_HT)
 868                         return true;
 869                 return false;
 870         case NL80211_CHAN_HT40MINUS:
 871         case NL80211_CHAN_HT40PLUS:
 872                 return (wk_ct == oper_ct);
 873         }
 874         WARN_ON(1); /* shouldn't get here */
 875         return false;
 876 }
 877
 878 static enum nl80211_channel_type
 879 ieee80211_calc_ct(enum nl80211_channel_type wk_ct,
 880                   enum nl80211_channel_type oper_ct)
 881 {
 882         switch (wk_ct) {
 883         case NL80211_CHAN_NO_HT:
 884                 return oper_ct;
 885         case NL80211_CHAN_HT20:
 886                 if (oper_ct != NL80211_CHAN_NO_HT)
 887                         return oper_ct;
 888                 return wk_ct;
 889         case NL80211_CHAN_HT40MINUS:
 890         case NL80211_CHAN_HT40PLUS:
 891                 return wk_ct;
 892         }
 893         WARN_ON(1); /* shouldn't get here */
 894         return wk_ct;
 895 }
 896
 897
 898 static void ieee80211_work_timer(unsigned long data)
 899 {
 900         struct ieee80211_local *local = (void *) data;
 901
 902         if (local->quiescing)
 903                 return;
 904
 905         ieee80211_queue_work(&local->hw, &local->work_work);
 906 }
 907
 908 static void ieee80211_work_work(struct work_struct *work)
 909 {
 910         struct ieee80211_local *local =
 911                 container_of(work, struct ieee80211_local, work_work);
 912         struct sk_buff *skb;
 913         struct ieee80211_work *wk, *tmp;
 914         LIST_HEAD(free_work);
 915         enum work_action rma;
 916         bool remain_off_channel = false;
 917
 918         if (local->scanning)
 919                 return;
 920
 921         /*
 922          * ieee80211_queue_work() should have picked up most cases,
 923          * here we'll pick the rest.
 924          */
 925         if (WARN(local->suspended, "work scheduled while going to suspend\n"))
 926                 return;
 927
 928         /* first process frames to avoid timing out while a frame is pending */
 929         while ((skb = skb_dequeue(&local->work_skb_queue)))
 930                 ieee80211_work_rx_queued_mgmt(local, skb);
 931
 932         mutex_lock(&local->mtx);
 933
 934         ieee80211_recalc_idle(local);
 935
 936         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
 937                 bool started = wk->started;
 938
 939                 /* mark work as started if it's on the current off-channel */
 940                 if (!started && local->tmp_channel &&
 941                     wk->chan == local->tmp_channel &&
 942                     wk->chan_type == local->tmp_channel_type) {
 943                         started = true;
 944                         wk->timeout = jiffies;
 945                 }
 946
 947                 if (!started && !local->tmp_channel) {
 948                         bool on_oper_chan;
 949                         bool tmp_chan_changed = false;
 950                         bool on_oper_chan2;
 951                         enum nl80211_channel_type wk_ct;
 952                         on_oper_chan = ieee80211_cfg_on_oper_channel(local);
 953
 954                         /* Work with existing channel type if possible. */
 955                         wk_ct = wk->chan_type;
 956                         if (wk->chan == local->hw.conf.channel)
 957                                 wk_ct = ieee80211_calc_ct(wk->chan_type,
 958                                                 local->hw.conf.channel_type);
 959
 960                         if (local->tmp_channel)
 961                                 if ((local->tmp_channel != wk->chan) ||
 962                                     (local->tmp_channel_type != wk_ct))
 963                                         tmp_chan_changed = true;
 964
 965                         local->tmp_channel = wk->chan;
 966                         local->tmp_channel_type = wk_ct;
 967                         /*
 968                          * Leave the station vifs in awake mode if they
 969                          * happen to be on the same channel as
 970                          * the requested channel.
 971                          */
 972                         on_oper_chan2 = ieee80211_cfg_on_oper_channel(local);
 973                         if (on_oper_chan != on_oper_chan2) {
 974                                 if (on_oper_chan2) {
 975                                         /* going off oper channel, PS too */
 976                                         ieee80211_offchannel_stop_vifs(local,
 977                                                                        true);
 978                                         ieee80211_hw_config(local, 0);
 979                                 } else {
 980                                         /* going on channel, but leave PS
 981                                          * off-channel. */
 982                                         ieee80211_hw_config(local, 0);
 983                                         ieee80211_offchannel_return(local,
 984                                                                     true,
 985                                                                     false);
 986                                 }
 987                         } else if (tmp_chan_changed)
 988                                 /* Still off-channel, but on some other
 989                                  * channel, so update hardware.
 990                                  * PS should already be off-channel.
 991                                  */
 992                                 ieee80211_hw_config(local, 0);
 993
 994                         started = true;
 995                         wk->timeout = jiffies;
 996                 }
 997
 998                 /* don't try to work with items that aren't started */
 999                 if (!started)
1000                         continue;
1001
1002                 if (time_is_after_jiffies(wk->timeout)) {
1003                         /*
1004                          * This work item isn't supposed to be worked on
1005                          * right now, but take care to adjust the timer
1006                          * properly.
1007                          */
1008                         run_again(local, wk->timeout);
1009                         continue;
1010                 }
1011
1012                 switch (wk->type) {
1013                 default:
1014                         WARN_ON(1);
1015                         /* nothing */
1016                         rma = WORK_ACT_NONE;
1017                         break;
1018                 case IEEE80211_WORK_ABORT:
1019                         rma = WORK_ACT_TIMEOUT;
1020                         break;
1021                 case IEEE80211_WORK_DIRECT_PROBE:
1022                         rma = ieee80211_direct_probe(wk);
1023                         break;
1024                 case IEEE80211_WORK_AUTH:
1025                         rma = ieee80211_authenticate(wk);
1026                         break;
1027                 case IEEE80211_WORK_ASSOC:
1028                         rma = ieee80211_associate(wk);
1029                         break;
1030                 case IEEE80211_WORK_REMAIN_ON_CHANNEL:
1031                         rma = ieee80211_remain_on_channel_timeout(wk);
1032                         break;
1033                 case IEEE80211_WORK_OFFCHANNEL_TX:
1034                         rma = ieee80211_offchannel_tx(wk);
1035                         break;
1036                 case IEEE80211_WORK_ASSOC_BEACON_WAIT:
1037                         rma = ieee80211_assoc_beacon_wait(wk);
1038                         break;
1039                 }
1040
1041                 wk->started = started;
1042
1043                 switch (rma) {
1044                 case WORK_ACT_NONE:
1045                         /* might have changed the timeout */
1046                         run_again(local, wk->timeout);
1047                         break;
1048                 case WORK_ACT_TIMEOUT:
1049                         list_del_rcu(&wk->list);
1050                         synchronize_rcu();
1051                         list_add(&wk->list, &free_work);
1052                         break;
1053                 default:
1054                         WARN(1, "unexpected: %d", rma);
1055                 }
1056         }
1057
1058         list_for_each_entry(wk, &local->work_list, list) {
1059                 if (!wk->started)
1060                         continue;
1061                 if (wk->chan != local->tmp_channel)
1062                         continue;
1063                 if (ieee80211_work_ct_coexists(wk->chan_type,
1064                                                local->tmp_channel_type))
1065                         continue;
1066                 remain_off_channel = true;
1067         }
1068
1069         if (!remain_off_channel && local->tmp_channel) {
1070                 bool on_oper_chan = ieee80211_cfg_on_oper_channel(local);
1071                 local->tmp_channel = NULL;
1072                 /* If tmp_channel wasn't operating channel, then
1073                  * we need to go back on-channel.
1074                  * NOTE:  If we can ever be here while scannning,
1075                  * or if the hw_config() channel config logic changes,
1076                  * then we may need to do a more thorough check to see if
1077                  * we still need to do a hardware config.  Currently,
1078                  * we cannot be here while scanning, however.
1079                  */
1080                 if (ieee80211_cfg_on_oper_channel(local) && !on_oper_chan)
1081                         ieee80211_hw_config(local, 0);
1082
1083                 /* At the least, we need to disable offchannel_ps,
1084                  * so just go ahead and run the entire offchannel
1085                  * return logic here.  We *could* skip enabling
1086                  * beaconing if we were already on-oper-channel
1087                  * as a future optimization.
1088                  */
1089                 ieee80211_offchannel_return(local, true, true);
1090
1091                 /* give connection some time to breathe */
1092                 run_again(local, jiffies + HZ/2);
1093         }
1094
1095         if (list_empty(&local->work_list) && local->scan_req &&
1096             !local->scanning)
1097                 ieee80211_queue_delayed_work(&local->hw,
1098                                              &local->scan_work,
1099                                              round_jiffies_relative(0));
1100
1101         ieee80211_recalc_idle(local);
1102
1103         mutex_unlock(&local->mtx);
1104
1105         list_for_each_entry_safe(wk, tmp, &free_work, list) {
1106                 wk->done(wk, NULL);
1107                 list_del(&wk->list);
1108                 kfree(wk);
1109         }
1110 }
1111
1112 void ieee80211_add_work(struct ieee80211_work *wk)
1113 {
1114         struct ieee80211_local *local;
1115
1116         if (WARN_ON(!wk->chan))
1117                 return;
1118
1119         if (WARN_ON(!wk->sdata))
1120                 return;
1121
1122         if (WARN_ON(!wk->done))
1123                 return;
1124
1125         if (WARN_ON(!ieee80211_sdata_running(wk->sdata)))
1126                 return;
1127
1128         wk->started = false;
1129
1130         local = wk->sdata->local;
1131         mutex_lock(&local->mtx);
1132         list_add_tail(&wk->list, &local->work_list);
1133         mutex_unlock(&local->mtx);
1134
1135         ieee80211_queue_work(&local->hw, &local->work_work);
1136 }
1137
1138 void ieee80211_work_init(struct ieee80211_local *local)
1139 {
1140         INIT_LIST_HEAD(&local->work_list);
1141         setup_timer(&local->work_timer, ieee80211_work_timer,
1142                     (unsigned long)local);
1143         INIT_WORK(&local->work_work, ieee80211_work_work);
1144         skb_queue_head_init(&local->work_skb_queue);
1145 }
1146
1147 void ieee80211_work_purge(struct ieee80211_sub_if_data *sdata)
1148 {
1149         struct ieee80211_local *local = sdata->local;
1150         struct ieee80211_work *wk;
1151         bool cleanup = false;
1152
1153         mutex_lock(&local->mtx);
1154         list_for_each_entry(wk, &local->work_list, list) {
1155                 if (wk->sdata != sdata)
1156                         continue;
1157                 cleanup = true;
1158                 wk->type = IEEE80211_WORK_ABORT;
1159                 wk->started = true;
1160                 wk->timeout = jiffies;
1161         }
1162         mutex_unlock(&local->mtx);
1163
1164         /* run cleanups etc. */
1165         if (cleanup)
1166                 ieee80211_work_work(&local->work_work);
1167
1168         mutex_lock(&local->mtx);
1169         list_for_each_entry(wk, &local->work_list, list) {
1170                 if (wk->sdata != sdata)
1171                         continue;
1172                 WARN_ON(1);
1173                 break;
1174         }
1175         mutex_unlock(&local->mtx);
1176 }
1177
1178 ieee80211_rx_result ieee80211_work_rx_mgmt(struct ieee80211_sub_if_data *sdata,
1179                                            struct sk_buff *skb)
1180 {
1181         struct ieee80211_local *local = sdata->local;
1182         struct ieee80211_mgmt *mgmt;
1183         struct ieee80211_work *wk;
1184         u16 fc;
1185
1186         if (skb->len < 24)
1187                 return RX_DROP_MONITOR;
1188
1189         mgmt = (struct ieee80211_mgmt *) skb->data;
1190         fc = le16_to_cpu(mgmt->frame_control);
1191
1192         list_for_each_entry_rcu(wk, &local->work_list, list) {
1193                 if (sdata != wk->sdata)
1194                         continue;
1195                 if (compare_ether_addr(wk->filter_ta, mgmt->sa))
1196                         continue;
1197                 if (compare_ether_addr(wk->filter_ta, mgmt->bssid))
1198                         continue;
1199
1200                 switch (fc & IEEE80211_FCTL_STYPE) {
1201                 case IEEE80211_STYPE_AUTH:
1202                 case IEEE80211_STYPE_PROBE_RESP:
1203                 case IEEE80211_STYPE_ASSOC_RESP:
1204                 case IEEE80211_STYPE_REASSOC_RESP:
1205                 case IEEE80211_STYPE_BEACON:
1206                         skb_queue_tail(&local->work_skb_queue, skb);
1207                         ieee80211_queue_work(&local->hw, &local->work_work);
1208                         return RX_QUEUED;
1209                 }
1210         }
1211
1212         return RX_CONTINUE;
1213 }
1214
1215 static enum work_done_result ieee80211_remain_done(struct ieee80211_work *wk,
1216                                                    struct sk_buff *skb)
1217 {
1218         /*
1219          * We are done serving the remain-on-channel command.
1220          */
1221         cfg80211_remain_on_channel_expired(wk->sdata->dev, (unsigned long) wk,
1222                                            wk->chan, wk->chan_type,
1223                                            GFP_KERNEL);
1224
1225         return WORK_DONE_DESTROY;
1226 }
1227
1228 int ieee80211_wk_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1229                                    struct ieee80211_channel *chan,
1230                                    enum nl80211_channel_type channel_type,
1231                                    unsigned int duration, u64 *cookie)
1232 {
1233         struct ieee80211_work *wk;
1234
1235         wk = kzalloc(sizeof(*wk), GFP_KERNEL);
1236         if (!wk)
1237                 return -ENOMEM;
1238
1239         wk->type = IEEE80211_WORK_REMAIN_ON_CHANNEL;
1240         wk->chan = chan;
1241         wk->chan_type = channel_type;
1242         wk->sdata = sdata;
1243         wk->done = ieee80211_remain_done;
1244
1245         wk->remain.duration = duration;
1246
1247         *cookie = (unsigned long) wk;
1248
1249         ieee80211_add_work(wk);
1250
1251         return 0;
1252 }
1253
1254 int ieee80211_wk_cancel_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1255                                           u64 cookie)
1256 {
1257         struct ieee80211_local *local = sdata->local;
1258         struct ieee80211_work *wk, *tmp;
1259         bool found = false;
1260
1261         mutex_lock(&local->mtx);
1262         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
1263                 if ((unsigned long) wk == cookie) {
1264                         wk->timeout = jiffies;
1265                         found = true;
1266                         break;
1267                 }
1268         }
1269         mutex_unlock(&local->mtx);
1270
1271         if (!found)
1272                 return -ENOENT;
1273
1274         ieee80211_queue_work(&local->hw, &local->work_work);
1275
1276         return 0;
1277 }