Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
[pandora-kernel.git] / 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 #include "driver-ops.h"
29
30 #define IEEE80211_AUTH_TIMEOUT (HZ / 5)
31 #define IEEE80211_AUTH_MAX_TRIES 3
32 #define IEEE80211_ASSOC_TIMEOUT (HZ / 5)
33 #define IEEE80211_ASSOC_MAX_TRIES 3
34
35 enum work_action {
36         WORK_ACT_MISMATCH,
37         WORK_ACT_NONE,
38         WORK_ACT_TIMEOUT,
39         WORK_ACT_DONE,
40 };
41
42
43 /* utils */
44 static inline void ASSERT_WORK_MTX(struct ieee80211_local *local)
45 {
46         lockdep_assert_held(&local->mtx);
47 }
48
49 /*
50  * We can have multiple work items (and connection probing)
51  * scheduling this timer, but we need to take care to only
52  * reschedule it when it should fire _earlier_ than it was
53  * asked for before, or if it's not pending right now. This
54  * function ensures that. Note that it then is required to
55  * run this function for all timeouts after the first one
56  * has happened -- the work that runs from this timer will
57  * do that.
58  */
59 static void run_again(struct ieee80211_local *local,
60                       unsigned long timeout)
61 {
62         ASSERT_WORK_MTX(local);
63
64         if (!timer_pending(&local->work_timer) ||
65             time_before(timeout, local->work_timer.expires))
66                 mod_timer(&local->work_timer, timeout);
67 }
68
69 void free_work(struct ieee80211_work *wk)
70 {
71         kfree_rcu(wk, rcu_head);
72 }
73
74 static int ieee80211_compatible_rates(const u8 *supp_rates, int supp_rates_len,
75                                       struct ieee80211_supported_band *sband,
76                                       u32 *rates)
77 {
78         int i, j, count;
79         *rates = 0;
80         count = 0;
81         for (i = 0; i < supp_rates_len; i++) {
82                 int rate = (supp_rates[i] & 0x7F) * 5;
83
84                 for (j = 0; j < sband->n_bitrates; j++)
85                         if (sband->bitrates[j].bitrate == rate) {
86                                 *rates |= BIT(j);
87                                 count++;
88                                 break;
89                         }
90         }
91
92         return count;
93 }
94
95 /* frame sending functions */
96
97 static void ieee80211_add_ht_ie(struct sk_buff *skb, const u8 *ht_info_ie,
98                                 struct ieee80211_supported_band *sband,
99                                 struct ieee80211_channel *channel,
100                                 enum ieee80211_smps_mode smps)
101 {
102         struct ieee80211_ht_info *ht_info;
103         u8 *pos;
104         u32 flags = channel->flags;
105         u16 cap = sband->ht_cap.cap;
106         __le16 tmp;
107
108         if (!sband->ht_cap.ht_supported)
109                 return;
110
111         if (!ht_info_ie)
112                 return;
113
114         if (ht_info_ie[1] < sizeof(struct ieee80211_ht_info))
115                 return;
116
117         ht_info = (struct ieee80211_ht_info *)(ht_info_ie + 2);
118
119         /* determine capability flags */
120
121         switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
122         case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
123                 if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
124                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
125                         cap &= ~IEEE80211_HT_CAP_SGI_40;
126                 }
127                 break;
128         case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
129                 if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
130                         cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
131                         cap &= ~IEEE80211_HT_CAP_SGI_40;
132                 }
133                 break;
134         }
135
136         /* set SM PS mode properly */
137         cap &= ~IEEE80211_HT_CAP_SM_PS;
138         switch (smps) {
139         case IEEE80211_SMPS_AUTOMATIC:
140         case IEEE80211_SMPS_NUM_MODES:
141                 WARN_ON(1);
142         case IEEE80211_SMPS_OFF:
143                 cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
144                         IEEE80211_HT_CAP_SM_PS_SHIFT;
145                 break;
146         case IEEE80211_SMPS_STATIC:
147                 cap |= WLAN_HT_CAP_SM_PS_STATIC <<
148                         IEEE80211_HT_CAP_SM_PS_SHIFT;
149                 break;
150         case IEEE80211_SMPS_DYNAMIC:
151                 cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
152                         IEEE80211_HT_CAP_SM_PS_SHIFT;
153                 break;
154         }
155
156         /* reserve and fill IE */
157
158         pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
159         *pos++ = WLAN_EID_HT_CAPABILITY;
160         *pos++ = sizeof(struct ieee80211_ht_cap);
161         memset(pos, 0, sizeof(struct ieee80211_ht_cap));
162
163         /* capability flags */
164         tmp = cpu_to_le16(cap);
165         memcpy(pos, &tmp, sizeof(u16));
166         pos += sizeof(u16);
167
168         /* AMPDU parameters */
169         *pos++ = sband->ht_cap.ampdu_factor |
170                  (sband->ht_cap.ampdu_density <<
171                         IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
172
173         /* MCS set */
174         memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
175         pos += sizeof(sband->ht_cap.mcs);
176
177         /* extended capabilities */
178         pos += sizeof(__le16);
179
180         /* BF capabilities */
181         pos += sizeof(__le32);
182
183         /* antenna selection */
184         pos += sizeof(u8);
185 }
186
187 static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
188                                  struct ieee80211_work *wk)
189 {
190         struct ieee80211_local *local = sdata->local;
191         struct sk_buff *skb;
192         struct ieee80211_mgmt *mgmt;
193         u8 *pos, qos_info;
194         size_t offset = 0, noffset;
195         int i, count, rates_len, supp_rates_len;
196         u16 capab;
197         struct ieee80211_supported_band *sband;
198         u32 rates = 0;
199
200         sband = local->hw.wiphy->bands[wk->chan->band];
201
202         if (wk->assoc.supp_rates_len) {
203                 /*
204                  * Get all rates supported by the device and the AP as
205                  * some APs don't like getting a superset of their rates
206                  * in the association request (e.g. D-Link DAP 1353 in
207                  * b-only mode)...
208                  */
209                 rates_len = ieee80211_compatible_rates(wk->assoc.supp_rates,
210                                                        wk->assoc.supp_rates_len,
211                                                        sband, &rates);
212         } else {
213                 /*
214                  * In case AP not provide any supported rates information
215                  * before association, we send information element(s) with
216                  * all rates that we support.
217                  */
218                 rates = ~0;
219                 rates_len = sband->n_bitrates;
220         }
221
222         skb = alloc_skb(local->hw.extra_tx_headroom +
223                         sizeof(*mgmt) + /* bit too much but doesn't matter */
224                         2 + wk->assoc.ssid_len + /* SSID */
225                         4 + rates_len + /* (extended) rates */
226                         4 + /* power capability */
227                         2 + 2 * sband->n_channels + /* supported channels */
228                         2 + sizeof(struct ieee80211_ht_cap) + /* HT */
229                         wk->ie_len + /* extra IEs */
230                         9, /* WMM */
231                         GFP_KERNEL);
232         if (!skb) {
233                 printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
234                        "frame\n", sdata->name);
235                 return;
236         }
237         skb_reserve(skb, local->hw.extra_tx_headroom);
238
239         capab = WLAN_CAPABILITY_ESS;
240
241         if (sband->band == IEEE80211_BAND_2GHZ) {
242                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
243                         capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
244                 if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
245                         capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
246         }
247
248         if (wk->assoc.capability & WLAN_CAPABILITY_PRIVACY)
249                 capab |= WLAN_CAPABILITY_PRIVACY;
250
251         if ((wk->assoc.capability & WLAN_CAPABILITY_SPECTRUM_MGMT) &&
252             (local->hw.flags & IEEE80211_HW_SPECTRUM_MGMT))
253                 capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;
254
255         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
256         memset(mgmt, 0, 24);
257         memcpy(mgmt->da, wk->filter_ta, ETH_ALEN);
258         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
259         memcpy(mgmt->bssid, wk->filter_ta, ETH_ALEN);
260
261         if (!is_zero_ether_addr(wk->assoc.prev_bssid)) {
262                 skb_put(skb, 10);
263                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
264                                                   IEEE80211_STYPE_REASSOC_REQ);
265                 mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
266                 mgmt->u.reassoc_req.listen_interval =
267                                 cpu_to_le16(local->hw.conf.listen_interval);
268                 memcpy(mgmt->u.reassoc_req.current_ap, wk->assoc.prev_bssid,
269                        ETH_ALEN);
270         } else {
271                 skb_put(skb, 4);
272                 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
273                                                   IEEE80211_STYPE_ASSOC_REQ);
274                 mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
275                 mgmt->u.assoc_req.listen_interval =
276                                 cpu_to_le16(local->hw.conf.listen_interval);
277         }
278
279         /* SSID */
280         pos = skb_put(skb, 2 + wk->assoc.ssid_len);
281         *pos++ = WLAN_EID_SSID;
282         *pos++ = wk->assoc.ssid_len;
283         memcpy(pos, wk->assoc.ssid, wk->assoc.ssid_len);
284
285         /* add all rates which were marked to be used above */
286         supp_rates_len = rates_len;
287         if (supp_rates_len > 8)
288                 supp_rates_len = 8;
289
290         pos = skb_put(skb, supp_rates_len + 2);
291         *pos++ = WLAN_EID_SUPP_RATES;
292         *pos++ = supp_rates_len;
293
294         count = 0;
295         for (i = 0; i < sband->n_bitrates; i++) {
296                 if (BIT(i) & rates) {
297                         int rate = sband->bitrates[i].bitrate;
298                         *pos++ = (u8) (rate / 5);
299                         if (++count == 8)
300                                 break;
301                 }
302         }
303
304         if (rates_len > count) {
305                 pos = skb_put(skb, rates_len - count + 2);
306                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
307                 *pos++ = rates_len - count;
308
309                 for (i++; i < sband->n_bitrates; i++) {
310                         if (BIT(i) & rates) {
311                                 int rate = sband->bitrates[i].bitrate;
312                                 *pos++ = (u8) (rate / 5);
313                         }
314                 }
315         }
316
317         if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT) {
318                 /* 1. power capabilities */
319                 pos = skb_put(skb, 4);
320                 *pos++ = WLAN_EID_PWR_CAPABILITY;
321                 *pos++ = 2;
322                 *pos++ = 0; /* min tx power */
323                 *pos++ = wk->chan->max_power; /* max tx power */
324
325                 /* 2. supported channels */
326                 /* TODO: get this in reg domain format */
327                 pos = skb_put(skb, 2 * sband->n_channels + 2);
328                 *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
329                 *pos++ = 2 * sband->n_channels;
330                 for (i = 0; i < sband->n_channels; i++) {
331                         *pos++ = ieee80211_frequency_to_channel(
332                                         sband->channels[i].center_freq);
333                         *pos++ = 1; /* one channel in the subband*/
334                 }
335         }
336
337         /* if present, add any custom IEs that go before HT */
338         if (wk->ie_len && wk->ie) {
339                 static const u8 before_ht[] = {
340                         WLAN_EID_SSID,
341                         WLAN_EID_SUPP_RATES,
342                         WLAN_EID_EXT_SUPP_RATES,
343                         WLAN_EID_PWR_CAPABILITY,
344                         WLAN_EID_SUPPORTED_CHANNELS,
345                         WLAN_EID_RSN,
346                         WLAN_EID_QOS_CAPA,
347                         WLAN_EID_RRM_ENABLED_CAPABILITIES,
348                         WLAN_EID_MOBILITY_DOMAIN,
349                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
350                 };
351                 noffset = ieee80211_ie_split(wk->ie, wk->ie_len,
352                                              before_ht, ARRAY_SIZE(before_ht),
353                                              offset);
354                 pos = skb_put(skb, noffset - offset);
355                 memcpy(pos, wk->ie + offset, noffset - offset);
356                 offset = noffset;
357         }
358
359         if (wk->assoc.use_11n && wk->assoc.wmm_used &&
360             local->hw.queues >= 4)
361                 ieee80211_add_ht_ie(skb, wk->assoc.ht_information_ie,
362                                     sband, wk->chan, wk->assoc.smps);
363
364         /* if present, add any custom non-vendor IEs that go after HT */
365         if (wk->ie_len && wk->ie) {
366                 noffset = ieee80211_ie_split_vendor(wk->ie, wk->ie_len,
367                                                     offset);
368                 pos = skb_put(skb, noffset - offset);
369                 memcpy(pos, wk->ie + offset, noffset - offset);
370                 offset = noffset;
371         }
372
373         if (wk->assoc.wmm_used && local->hw.queues >= 4) {
374                 if (wk->assoc.uapsd_used) {
375                         qos_info = local->uapsd_queues;
376                         qos_info |= (local->uapsd_max_sp_len <<
377                                      IEEE80211_WMM_IE_STA_QOSINFO_SP_SHIFT);
378                 } else {
379                         qos_info = 0;
380                 }
381
382                 pos = skb_put(skb, 9);
383                 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
384                 *pos++ = 7; /* len */
385                 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
386                 *pos++ = 0x50;
387                 *pos++ = 0xf2;
388                 *pos++ = 2; /* WME */
389                 *pos++ = 0; /* WME info */
390                 *pos++ = 1; /* WME ver */
391                 *pos++ = qos_info;
392         }
393
394         /* add any remaining custom (i.e. vendor specific here) IEs */
395         if (wk->ie_len && wk->ie) {
396                 noffset = wk->ie_len;
397                 pos = skb_put(skb, noffset - offset);
398                 memcpy(pos, wk->ie + offset, noffset - offset);
399         }
400
401         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
402         ieee80211_tx_skb(sdata, skb);
403 }
404
405 static void ieee80211_remove_auth_bss(struct ieee80211_local *local,
406                                       struct ieee80211_work *wk)
407 {
408         struct cfg80211_bss *cbss;
409         u16 capa_val = WLAN_CAPABILITY_ESS;
410
411         if (wk->probe_auth.privacy)
412                 capa_val |= WLAN_CAPABILITY_PRIVACY;
413
414         cbss = cfg80211_get_bss(local->hw.wiphy, wk->chan, wk->filter_ta,
415                                 wk->probe_auth.ssid, wk->probe_auth.ssid_len,
416                                 WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_PRIVACY,
417                                 capa_val);
418         if (!cbss)
419                 return;
420
421         cfg80211_unlink_bss(local->hw.wiphy, cbss);
422         cfg80211_put_bss(cbss);
423 }
424
425 static enum work_action __must_check
426 ieee80211_direct_probe(struct ieee80211_work *wk)
427 {
428         struct ieee80211_sub_if_data *sdata = wk->sdata;
429         struct ieee80211_local *local = sdata->local;
430
431         if (!wk->probe_auth.synced) {
432                 int ret = drv_tx_sync(local, sdata, wk->filter_ta,
433                                       IEEE80211_TX_SYNC_AUTH);
434                 if (ret)
435                         return WORK_ACT_TIMEOUT;
436         }
437         wk->probe_auth.synced = true;
438
439         wk->probe_auth.tries++;
440         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
441                 printk(KERN_DEBUG "%s: direct probe to %pM timed out\n",
442                        sdata->name, wk->filter_ta);
443
444                 /*
445                  * Most likely AP is not in the range so remove the
446                  * bss struct for that AP.
447                  */
448                 ieee80211_remove_auth_bss(local, wk);
449
450                 return WORK_ACT_TIMEOUT;
451         }
452
453         printk(KERN_DEBUG "%s: direct probe to %pM (try %d/%i)\n",
454                sdata->name, wk->filter_ta, wk->probe_auth.tries,
455                IEEE80211_AUTH_MAX_TRIES);
456
457         /*
458          * Direct probe is sent to broadcast address as some APs
459          * will not answer to direct packet in unassociated state.
460          */
461         ieee80211_send_probe_req(sdata, NULL, wk->probe_auth.ssid,
462                                  wk->probe_auth.ssid_len, NULL, 0,
463                                  (u32) -1, true);
464
465         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
466         run_again(local, wk->timeout);
467
468         return WORK_ACT_NONE;
469 }
470
471
472 static enum work_action __must_check
473 ieee80211_authenticate(struct ieee80211_work *wk)
474 {
475         struct ieee80211_sub_if_data *sdata = wk->sdata;
476         struct ieee80211_local *local = sdata->local;
477
478         if (!wk->probe_auth.synced) {
479                 int ret = drv_tx_sync(local, sdata, wk->filter_ta,
480                                       IEEE80211_TX_SYNC_AUTH);
481                 if (ret)
482                         return WORK_ACT_TIMEOUT;
483         }
484         wk->probe_auth.synced = true;
485
486         wk->probe_auth.tries++;
487         if (wk->probe_auth.tries > IEEE80211_AUTH_MAX_TRIES) {
488                 printk(KERN_DEBUG "%s: authentication with %pM"
489                        " timed out\n", sdata->name, wk->filter_ta);
490
491                 /*
492                  * Most likely AP is not in the range so remove the
493                  * bss struct for that AP.
494                  */
495                 ieee80211_remove_auth_bss(local, wk);
496
497                 return WORK_ACT_TIMEOUT;
498         }
499
500         printk(KERN_DEBUG "%s: authenticate with %pM (try %d)\n",
501                sdata->name, wk->filter_ta, wk->probe_auth.tries);
502
503         ieee80211_send_auth(sdata, 1, wk->probe_auth.algorithm, wk->ie,
504                             wk->ie_len, wk->filter_ta, NULL, 0, 0);
505         wk->probe_auth.transaction = 2;
506
507         wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
508         run_again(local, wk->timeout);
509
510         return WORK_ACT_NONE;
511 }
512
513 static enum work_action __must_check
514 ieee80211_associate(struct ieee80211_work *wk)
515 {
516         struct ieee80211_sub_if_data *sdata = wk->sdata;
517         struct ieee80211_local *local = sdata->local;
518
519         if (!wk->assoc.synced) {
520                 int ret = drv_tx_sync(local, sdata, wk->filter_ta,
521                                       IEEE80211_TX_SYNC_ASSOC);
522                 if (ret)
523                         return WORK_ACT_TIMEOUT;
524         }
525         wk->assoc.synced = true;
526
527         wk->assoc.tries++;
528         if (wk->assoc.tries > IEEE80211_ASSOC_MAX_TRIES) {
529                 printk(KERN_DEBUG "%s: association with %pM"
530                        " timed out\n",
531                        sdata->name, wk->filter_ta);
532
533                 /*
534                  * Most likely AP is not in the range so remove the
535                  * bss struct for that AP.
536                  */
537                 if (wk->assoc.bss)
538                         cfg80211_unlink_bss(local->hw.wiphy, wk->assoc.bss);
539
540                 return WORK_ACT_TIMEOUT;
541         }
542
543         printk(KERN_DEBUG "%s: associate with %pM (try %d)\n",
544                sdata->name, wk->filter_ta, wk->assoc.tries);
545         ieee80211_send_assoc(sdata, wk);
546
547         wk->timeout = jiffies + IEEE80211_ASSOC_TIMEOUT;
548         run_again(local, wk->timeout);
549
550         return WORK_ACT_NONE;
551 }
552
553 static enum work_action __must_check
554 ieee80211_remain_on_channel_timeout(struct ieee80211_work *wk)
555 {
556         /*
557          * First time we run, do nothing -- the generic code will
558          * have switched to the right channel etc.
559          */
560         if (!wk->started) {
561                 wk->timeout = jiffies + msecs_to_jiffies(wk->remain.duration);
562
563                 cfg80211_ready_on_channel(wk->sdata->dev, (unsigned long) wk,
564                                           wk->chan, wk->chan_type,
565                                           wk->remain.duration, GFP_KERNEL);
566
567                 return WORK_ACT_NONE;
568         }
569
570         return WORK_ACT_TIMEOUT;
571 }
572
573 static enum work_action __must_check
574 ieee80211_offchannel_tx(struct ieee80211_work *wk)
575 {
576         if (!wk->started) {
577                 wk->timeout = jiffies + msecs_to_jiffies(wk->offchan_tx.wait);
578
579                 /*
580                  * After this, offchan_tx.frame remains but now is no
581                  * longer a valid pointer -- we still need it as the
582                  * cookie for canceling this work.
583                  */
584                 ieee80211_tx_skb(wk->sdata, wk->offchan_tx.frame);
585
586                 return WORK_ACT_NONE;
587         }
588
589         return WORK_ACT_TIMEOUT;
590 }
591
592 static enum work_action __must_check
593 ieee80211_assoc_beacon_wait(struct ieee80211_work *wk)
594 {
595         if (wk->started)
596                 return WORK_ACT_TIMEOUT;
597
598         /*
599          * Wait up to one beacon interval ...
600          * should this be more if we miss one?
601          */
602         printk(KERN_DEBUG "%s: waiting for beacon from %pM\n",
603                wk->sdata->name, wk->filter_ta);
604         wk->timeout = TU_TO_EXP_TIME(wk->assoc.bss->beacon_interval);
605         return WORK_ACT_NONE;
606 }
607
608 static void ieee80211_auth_challenge(struct ieee80211_work *wk,
609                                      struct ieee80211_mgmt *mgmt,
610                                      size_t len)
611 {
612         struct ieee80211_sub_if_data *sdata = wk->sdata;
613         u8 *pos;
614         struct ieee802_11_elems elems;
615
616         pos = mgmt->u.auth.variable;
617         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
618         if (!elems.challenge)
619                 return;
620         ieee80211_send_auth(sdata, 3, wk->probe_auth.algorithm,
621                             elems.challenge - 2, elems.challenge_len + 2,
622                             wk->filter_ta, wk->probe_auth.key,
623                             wk->probe_auth.key_len, wk->probe_auth.key_idx);
624         wk->probe_auth.transaction = 4;
625 }
626
627 static enum work_action __must_check
628 ieee80211_rx_mgmt_auth(struct ieee80211_work *wk,
629                        struct ieee80211_mgmt *mgmt, size_t len)
630 {
631         u16 auth_alg, auth_transaction, status_code;
632
633         if (wk->type != IEEE80211_WORK_AUTH)
634                 return WORK_ACT_MISMATCH;
635
636         if (len < 24 + 6)
637                 return WORK_ACT_NONE;
638
639         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
640         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
641         status_code = le16_to_cpu(mgmt->u.auth.status_code);
642
643         if (auth_alg != wk->probe_auth.algorithm ||
644             auth_transaction != wk->probe_auth.transaction)
645                 return WORK_ACT_NONE;
646
647         if (status_code != WLAN_STATUS_SUCCESS) {
648                 printk(KERN_DEBUG "%s: %pM denied authentication (status %d)\n",
649                        wk->sdata->name, mgmt->sa, status_code);
650                 return WORK_ACT_DONE;
651         }
652
653         switch (wk->probe_auth.algorithm) {
654         case WLAN_AUTH_OPEN:
655         case WLAN_AUTH_LEAP:
656         case WLAN_AUTH_FT:
657                 break;
658         case WLAN_AUTH_SHARED_KEY:
659                 if (wk->probe_auth.transaction != 4) {
660                         ieee80211_auth_challenge(wk, mgmt, len);
661                         /* need another frame */
662                         return WORK_ACT_NONE;
663                 }
664                 break;
665         default:
666                 WARN_ON(1);
667                 return WORK_ACT_NONE;
668         }
669
670         printk(KERN_DEBUG "%s: authenticated\n", wk->sdata->name);
671         return WORK_ACT_DONE;
672 }
673
674 static enum work_action __must_check
675 ieee80211_rx_mgmt_assoc_resp(struct ieee80211_work *wk,
676                              struct ieee80211_mgmt *mgmt, size_t len,
677                              bool reassoc)
678 {
679         struct ieee80211_sub_if_data *sdata = wk->sdata;
680         struct ieee80211_local *local = sdata->local;
681         u16 capab_info, status_code, aid;
682         struct ieee802_11_elems elems;
683         u8 *pos;
684
685         if (wk->type != IEEE80211_WORK_ASSOC)
686                 return WORK_ACT_MISMATCH;
687
688         /*
689          * AssocResp and ReassocResp have identical structure, so process both
690          * of them in this function.
691          */
692
693         if (len < 24 + 6)
694                 return WORK_ACT_NONE;
695
696         capab_info = le16_to_cpu(mgmt->u.assoc_resp.capab_info);
697         status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
698         aid = le16_to_cpu(mgmt->u.assoc_resp.aid);
699
700         printk(KERN_DEBUG "%s: RX %sssocResp from %pM (capab=0x%x "
701                "status=%d aid=%d)\n",
702                sdata->name, reassoc ? "Rea" : "A", mgmt->sa,
703                capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));
704
705         pos = mgmt->u.assoc_resp.variable;
706         ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
707
708         if (status_code == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY &&
709             elems.timeout_int && elems.timeout_int_len == 5 &&
710             elems.timeout_int[0] == WLAN_TIMEOUT_ASSOC_COMEBACK) {
711                 u32 tu, ms;
712                 tu = get_unaligned_le32(elems.timeout_int + 1);
713                 ms = tu * 1024 / 1000;
714                 printk(KERN_DEBUG "%s: %pM rejected association temporarily; "
715                        "comeback duration %u TU (%u ms)\n",
716                        sdata->name, mgmt->sa, tu, ms);
717                 wk->timeout = jiffies + msecs_to_jiffies(ms);
718                 if (ms > IEEE80211_ASSOC_TIMEOUT)
719                         run_again(local, wk->timeout);
720                 return WORK_ACT_NONE;
721         }
722
723         if (status_code != WLAN_STATUS_SUCCESS)
724                 printk(KERN_DEBUG "%s: %pM denied association (code=%d)\n",
725                        sdata->name, mgmt->sa, status_code);
726         else
727                 printk(KERN_DEBUG "%s: associated\n", sdata->name);
728
729         return WORK_ACT_DONE;
730 }
731
732 static enum work_action __must_check
733 ieee80211_rx_mgmt_probe_resp(struct ieee80211_work *wk,
734                              struct ieee80211_mgmt *mgmt, size_t len,
735                              struct ieee80211_rx_status *rx_status)
736 {
737         struct ieee80211_sub_if_data *sdata = wk->sdata;
738         struct ieee80211_local *local = sdata->local;
739         size_t baselen;
740
741         ASSERT_WORK_MTX(local);
742
743         if (wk->type != IEEE80211_WORK_DIRECT_PROBE)
744                 return WORK_ACT_MISMATCH;
745
746         if (len < 24 + 12)
747                 return WORK_ACT_NONE;
748
749         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
750         if (baselen > len)
751                 return WORK_ACT_NONE;
752
753         printk(KERN_DEBUG "%s: direct probe responded\n", sdata->name);
754         return WORK_ACT_DONE;
755 }
756
757 static enum work_action __must_check
758 ieee80211_rx_mgmt_beacon(struct ieee80211_work *wk,
759                          struct ieee80211_mgmt *mgmt, size_t len)
760 {
761         struct ieee80211_sub_if_data *sdata = wk->sdata;
762         struct ieee80211_local *local = sdata->local;
763
764         ASSERT_WORK_MTX(local);
765
766         if (wk->type != IEEE80211_WORK_ASSOC_BEACON_WAIT)
767                 return WORK_ACT_MISMATCH;
768
769         if (len < 24 + 12)
770                 return WORK_ACT_NONE;
771
772         printk(KERN_DEBUG "%s: beacon received\n", sdata->name);
773         return WORK_ACT_DONE;
774 }
775
776 static void ieee80211_work_rx_queued_mgmt(struct ieee80211_local *local,
777                                           struct sk_buff *skb)
778 {
779         struct ieee80211_rx_status *rx_status;
780         struct ieee80211_mgmt *mgmt;
781         struct ieee80211_work *wk;
782         enum work_action rma = WORK_ACT_NONE;
783         u16 fc;
784
785         rx_status = (struct ieee80211_rx_status *) skb->cb;
786         mgmt = (struct ieee80211_mgmt *) skb->data;
787         fc = le16_to_cpu(mgmt->frame_control);
788
789         mutex_lock(&local->mtx);
790
791         list_for_each_entry(wk, &local->work_list, list) {
792                 const u8 *bssid = NULL;
793
794                 switch (wk->type) {
795                 case IEEE80211_WORK_DIRECT_PROBE:
796                 case IEEE80211_WORK_AUTH:
797                 case IEEE80211_WORK_ASSOC:
798                 case IEEE80211_WORK_ASSOC_BEACON_WAIT:
799                         bssid = wk->filter_ta;
800                         break;
801                 default:
802                         continue;
803                 }
804
805                 /*
806                  * Before queuing, we already verified mgmt->sa,
807                  * so this is needed just for matching.
808                  */
809                 if (compare_ether_addr(bssid, mgmt->bssid))
810                         continue;
811
812                 switch (fc & IEEE80211_FCTL_STYPE) {
813                 case IEEE80211_STYPE_BEACON:
814                         rma = ieee80211_rx_mgmt_beacon(wk, mgmt, skb->len);
815                         break;
816                 case IEEE80211_STYPE_PROBE_RESP:
817                         rma = ieee80211_rx_mgmt_probe_resp(wk, mgmt, skb->len,
818                                                            rx_status);
819                         break;
820                 case IEEE80211_STYPE_AUTH:
821                         rma = ieee80211_rx_mgmt_auth(wk, mgmt, skb->len);
822                         break;
823                 case IEEE80211_STYPE_ASSOC_RESP:
824                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
825                                                            skb->len, false);
826                         break;
827                 case IEEE80211_STYPE_REASSOC_RESP:
828                         rma = ieee80211_rx_mgmt_assoc_resp(wk, mgmt,
829                                                            skb->len, true);
830                         break;
831                 default:
832                         WARN_ON(1);
833                         rma = WORK_ACT_NONE;
834                 }
835
836                 /*
837                  * We've either received an unexpected frame, or we have
838                  * multiple work items and need to match the frame to the
839                  * right one.
840                  */
841                 if (rma == WORK_ACT_MISMATCH)
842                         continue;
843
844                 /*
845                  * We've processed this frame for that work, so it can't
846                  * belong to another work struct.
847                  * NB: this is also required for correctness for 'rma'!
848                  */
849                 break;
850         }
851
852         switch (rma) {
853         case WORK_ACT_MISMATCH:
854                 /* ignore this unmatched frame */
855                 break;
856         case WORK_ACT_NONE:
857                 break;
858         case WORK_ACT_DONE:
859                 list_del_rcu(&wk->list);
860                 break;
861         default:
862                 WARN(1, "unexpected: %d", rma);
863         }
864
865         mutex_unlock(&local->mtx);
866
867         if (rma != WORK_ACT_DONE)
868                 goto out;
869
870         switch (wk->done(wk, skb)) {
871         case WORK_DONE_DESTROY:
872                 free_work(wk);
873                 break;
874         case WORK_DONE_REQUEUE:
875                 synchronize_rcu();
876                 wk->started = false; /* restart */
877                 mutex_lock(&local->mtx);
878                 list_add_tail(&wk->list, &local->work_list);
879                 mutex_unlock(&local->mtx);
880         }
881
882  out:
883         kfree_skb(skb);
884 }
885
886 static bool ieee80211_work_ct_coexists(enum nl80211_channel_type wk_ct,
887                                        enum nl80211_channel_type oper_ct)
888 {
889         switch (wk_ct) {
890         case NL80211_CHAN_NO_HT:
891                 return true;
892         case NL80211_CHAN_HT20:
893                 if (oper_ct != NL80211_CHAN_NO_HT)
894                         return true;
895                 return false;
896         case NL80211_CHAN_HT40MINUS:
897         case NL80211_CHAN_HT40PLUS:
898                 return (wk_ct == oper_ct);
899         }
900         WARN_ON(1); /* shouldn't get here */
901         return false;
902 }
903
904 static enum nl80211_channel_type
905 ieee80211_calc_ct(enum nl80211_channel_type wk_ct,
906                   enum nl80211_channel_type oper_ct)
907 {
908         switch (wk_ct) {
909         case NL80211_CHAN_NO_HT:
910                 return oper_ct;
911         case NL80211_CHAN_HT20:
912                 if (oper_ct != NL80211_CHAN_NO_HT)
913                         return oper_ct;
914                 return wk_ct;
915         case NL80211_CHAN_HT40MINUS:
916         case NL80211_CHAN_HT40PLUS:
917                 return wk_ct;
918         }
919         WARN_ON(1); /* shouldn't get here */
920         return wk_ct;
921 }
922
923
924 static void ieee80211_work_timer(unsigned long data)
925 {
926         struct ieee80211_local *local = (void *) data;
927
928         if (local->quiescing)
929                 return;
930
931         ieee80211_queue_work(&local->hw, &local->work_work);
932 }
933
934 static void ieee80211_work_work(struct work_struct *work)
935 {
936         struct ieee80211_local *local =
937                 container_of(work, struct ieee80211_local, work_work);
938         struct sk_buff *skb;
939         struct ieee80211_work *wk, *tmp;
940         LIST_HEAD(free_work);
941         enum work_action rma;
942         bool remain_off_channel = false;
943
944         if (local->scanning)
945                 return;
946
947         /*
948          * ieee80211_queue_work() should have picked up most cases,
949          * here we'll pick the rest.
950          */
951         if (WARN(local->suspended, "work scheduled while going to suspend\n"))
952                 return;
953
954         /* first process frames to avoid timing out while a frame is pending */
955         while ((skb = skb_dequeue(&local->work_skb_queue)))
956                 ieee80211_work_rx_queued_mgmt(local, skb);
957
958         mutex_lock(&local->mtx);
959
960         ieee80211_recalc_idle(local);
961
962         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
963                 bool started = wk->started;
964
965                 /* mark work as started if it's on the current off-channel */
966                 if (!started && local->tmp_channel &&
967                     wk->chan == local->tmp_channel &&
968                     wk->chan_type == local->tmp_channel_type) {
969                         started = true;
970                         wk->timeout = jiffies;
971                 }
972
973                 if (!started && !local->tmp_channel) {
974                         bool on_oper_chan;
975                         bool tmp_chan_changed = false;
976                         bool on_oper_chan2;
977                         enum nl80211_channel_type wk_ct;
978                         on_oper_chan = ieee80211_cfg_on_oper_channel(local);
979
980                         /* Work with existing channel type if possible. */
981                         wk_ct = wk->chan_type;
982                         if (wk->chan == local->hw.conf.channel)
983                                 wk_ct = ieee80211_calc_ct(wk->chan_type,
984                                                 local->hw.conf.channel_type);
985
986                         if (local->tmp_channel)
987                                 if ((local->tmp_channel != wk->chan) ||
988                                     (local->tmp_channel_type != wk_ct))
989                                         tmp_chan_changed = true;
990
991                         local->tmp_channel = wk->chan;
992                         local->tmp_channel_type = wk_ct;
993                         /*
994                          * Leave the station vifs in awake mode if they
995                          * happen to be on the same channel as
996                          * the requested channel.
997                          */
998                         on_oper_chan2 = ieee80211_cfg_on_oper_channel(local);
999                         if (on_oper_chan != on_oper_chan2) {
1000                                 if (on_oper_chan2) {
1001                                         /* going off oper channel, PS too */
1002                                         ieee80211_offchannel_stop_vifs(local,
1003                                                                        true);
1004                                         ieee80211_hw_config(local, 0);
1005                                 } else {
1006                                         /* going on channel, but leave PS
1007                                          * off-channel. */
1008                                         ieee80211_hw_config(local, 0);
1009                                         ieee80211_offchannel_return(local,
1010                                                                     true,
1011                                                                     false);
1012                                 }
1013                         } else if (tmp_chan_changed)
1014                                 /* Still off-channel, but on some other
1015                                  * channel, so update hardware.
1016                                  * PS should already be off-channel.
1017                                  */
1018                                 ieee80211_hw_config(local, 0);
1019
1020                         started = true;
1021                         wk->timeout = jiffies;
1022                 }
1023
1024                 /* don't try to work with items that aren't started */
1025                 if (!started)
1026                         continue;
1027
1028                 if (time_is_after_jiffies(wk->timeout)) {
1029                         /*
1030                          * This work item isn't supposed to be worked on
1031                          * right now, but take care to adjust the timer
1032                          * properly.
1033                          */
1034                         run_again(local, wk->timeout);
1035                         continue;
1036                 }
1037
1038                 switch (wk->type) {
1039                 default:
1040                         WARN_ON(1);
1041                         /* nothing */
1042                         rma = WORK_ACT_NONE;
1043                         break;
1044                 case IEEE80211_WORK_ABORT:
1045                         rma = WORK_ACT_TIMEOUT;
1046                         break;
1047                 case IEEE80211_WORK_DIRECT_PROBE:
1048                         rma = ieee80211_direct_probe(wk);
1049                         break;
1050                 case IEEE80211_WORK_AUTH:
1051                         rma = ieee80211_authenticate(wk);
1052                         break;
1053                 case IEEE80211_WORK_ASSOC:
1054                         rma = ieee80211_associate(wk);
1055                         break;
1056                 case IEEE80211_WORK_REMAIN_ON_CHANNEL:
1057                         rma = ieee80211_remain_on_channel_timeout(wk);
1058                         break;
1059                 case IEEE80211_WORK_OFFCHANNEL_TX:
1060                         rma = ieee80211_offchannel_tx(wk);
1061                         break;
1062                 case IEEE80211_WORK_ASSOC_BEACON_WAIT:
1063                         rma = ieee80211_assoc_beacon_wait(wk);
1064                         break;
1065                 }
1066
1067                 wk->started = started;
1068
1069                 switch (rma) {
1070                 case WORK_ACT_NONE:
1071                         /* might have changed the timeout */
1072                         run_again(local, wk->timeout);
1073                         break;
1074                 case WORK_ACT_TIMEOUT:
1075                         list_del_rcu(&wk->list);
1076                         synchronize_rcu();
1077                         list_add(&wk->list, &free_work);
1078                         break;
1079                 default:
1080                         WARN(1, "unexpected: %d", rma);
1081                 }
1082         }
1083
1084         list_for_each_entry(wk, &local->work_list, list) {
1085                 if (!wk->started)
1086                         continue;
1087                 if (wk->chan != local->tmp_channel)
1088                         continue;
1089                 if (ieee80211_work_ct_coexists(wk->chan_type,
1090                                                local->tmp_channel_type))
1091                         continue;
1092                 remain_off_channel = true;
1093         }
1094
1095         if (!remain_off_channel && local->tmp_channel) {
1096                 bool on_oper_chan = ieee80211_cfg_on_oper_channel(local);
1097                 local->tmp_channel = NULL;
1098                 /* If tmp_channel wasn't operating channel, then
1099                  * we need to go back on-channel.
1100                  * NOTE:  If we can ever be here while scannning,
1101                  * or if the hw_config() channel config logic changes,
1102                  * then we may need to do a more thorough check to see if
1103                  * we still need to do a hardware config.  Currently,
1104                  * we cannot be here while scanning, however.
1105                  */
1106                 if (ieee80211_cfg_on_oper_channel(local) && !on_oper_chan)
1107                         ieee80211_hw_config(local, 0);
1108
1109                 /* At the least, we need to disable offchannel_ps,
1110                  * so just go ahead and run the entire offchannel
1111                  * return logic here.  We *could* skip enabling
1112                  * beaconing if we were already on-oper-channel
1113                  * as a future optimization.
1114                  */
1115                 ieee80211_offchannel_return(local, true, true);
1116
1117                 /* give connection some time to breathe */
1118                 run_again(local, jiffies + HZ/2);
1119         }
1120
1121         if (list_empty(&local->work_list) && local->scan_req &&
1122             !local->scanning)
1123                 ieee80211_queue_delayed_work(&local->hw,
1124                                              &local->scan_work,
1125                                              round_jiffies_relative(0));
1126
1127         ieee80211_recalc_idle(local);
1128
1129         mutex_unlock(&local->mtx);
1130
1131         list_for_each_entry_safe(wk, tmp, &free_work, list) {
1132                 wk->done(wk, NULL);
1133                 list_del(&wk->list);
1134                 kfree(wk);
1135         }
1136 }
1137
1138 void ieee80211_add_work(struct ieee80211_work *wk)
1139 {
1140         struct ieee80211_local *local;
1141
1142         if (WARN_ON(!wk->chan))
1143                 return;
1144
1145         if (WARN_ON(!wk->sdata))
1146                 return;
1147
1148         if (WARN_ON(!wk->done))
1149                 return;
1150
1151         if (WARN_ON(!ieee80211_sdata_running(wk->sdata)))
1152                 return;
1153
1154         wk->started = false;
1155
1156         local = wk->sdata->local;
1157         mutex_lock(&local->mtx);
1158         list_add_tail(&wk->list, &local->work_list);
1159         mutex_unlock(&local->mtx);
1160
1161         ieee80211_queue_work(&local->hw, &local->work_work);
1162 }
1163
1164 void ieee80211_work_init(struct ieee80211_local *local)
1165 {
1166         INIT_LIST_HEAD(&local->work_list);
1167         setup_timer(&local->work_timer, ieee80211_work_timer,
1168                     (unsigned long)local);
1169         INIT_WORK(&local->work_work, ieee80211_work_work);
1170         skb_queue_head_init(&local->work_skb_queue);
1171 }
1172
1173 void ieee80211_work_purge(struct ieee80211_sub_if_data *sdata)
1174 {
1175         struct ieee80211_local *local = sdata->local;
1176         struct ieee80211_work *wk;
1177         bool cleanup = false;
1178
1179         mutex_lock(&local->mtx);
1180         list_for_each_entry(wk, &local->work_list, list) {
1181                 if (wk->sdata != sdata)
1182                         continue;
1183                 cleanup = true;
1184                 wk->type = IEEE80211_WORK_ABORT;
1185                 wk->started = true;
1186                 wk->timeout = jiffies;
1187         }
1188         mutex_unlock(&local->mtx);
1189
1190         /* run cleanups etc. */
1191         if (cleanup)
1192                 ieee80211_work_work(&local->work_work);
1193
1194         mutex_lock(&local->mtx);
1195         list_for_each_entry(wk, &local->work_list, list) {
1196                 if (wk->sdata != sdata)
1197                         continue;
1198                 WARN_ON(1);
1199                 break;
1200         }
1201         mutex_unlock(&local->mtx);
1202 }
1203
1204 ieee80211_rx_result ieee80211_work_rx_mgmt(struct ieee80211_sub_if_data *sdata,
1205                                            struct sk_buff *skb)
1206 {
1207         struct ieee80211_local *local = sdata->local;
1208         struct ieee80211_mgmt *mgmt;
1209         struct ieee80211_work *wk;
1210         u16 fc;
1211
1212         if (skb->len < 24)
1213                 return RX_DROP_MONITOR;
1214
1215         mgmt = (struct ieee80211_mgmt *) skb->data;
1216         fc = le16_to_cpu(mgmt->frame_control);
1217
1218         list_for_each_entry_rcu(wk, &local->work_list, list) {
1219                 if (sdata != wk->sdata)
1220                         continue;
1221                 if (compare_ether_addr(wk->filter_ta, mgmt->sa))
1222                         continue;
1223                 if (compare_ether_addr(wk->filter_ta, mgmt->bssid))
1224                         continue;
1225
1226                 switch (fc & IEEE80211_FCTL_STYPE) {
1227                 case IEEE80211_STYPE_AUTH:
1228                 case IEEE80211_STYPE_PROBE_RESP:
1229                 case IEEE80211_STYPE_ASSOC_RESP:
1230                 case IEEE80211_STYPE_REASSOC_RESP:
1231                 case IEEE80211_STYPE_BEACON:
1232                         skb_queue_tail(&local->work_skb_queue, skb);
1233                         ieee80211_queue_work(&local->hw, &local->work_work);
1234                         return RX_QUEUED;
1235                 }
1236         }
1237
1238         return RX_CONTINUE;
1239 }
1240
1241 static enum work_done_result ieee80211_remain_done(struct ieee80211_work *wk,
1242                                                    struct sk_buff *skb)
1243 {
1244         /*
1245          * We are done serving the remain-on-channel command.
1246          */
1247         cfg80211_remain_on_channel_expired(wk->sdata->dev, (unsigned long) wk,
1248                                            wk->chan, wk->chan_type,
1249                                            GFP_KERNEL);
1250
1251         return WORK_DONE_DESTROY;
1252 }
1253
1254 int ieee80211_wk_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1255                                    struct ieee80211_channel *chan,
1256                                    enum nl80211_channel_type channel_type,
1257                                    unsigned int duration, u64 *cookie)
1258 {
1259         struct ieee80211_work *wk;
1260
1261         wk = kzalloc(sizeof(*wk), GFP_KERNEL);
1262         if (!wk)
1263                 return -ENOMEM;
1264
1265         wk->type = IEEE80211_WORK_REMAIN_ON_CHANNEL;
1266         wk->chan = chan;
1267         wk->chan_type = channel_type;
1268         wk->sdata = sdata;
1269         wk->done = ieee80211_remain_done;
1270
1271         wk->remain.duration = duration;
1272
1273         *cookie = (unsigned long) wk;
1274
1275         ieee80211_add_work(wk);
1276
1277         return 0;
1278 }
1279
1280 int ieee80211_wk_cancel_remain_on_channel(struct ieee80211_sub_if_data *sdata,
1281                                           u64 cookie)
1282 {
1283         struct ieee80211_local *local = sdata->local;
1284         struct ieee80211_work *wk, *tmp;
1285         bool found = false;
1286
1287         mutex_lock(&local->mtx);
1288         list_for_each_entry_safe(wk, tmp, &local->work_list, list) {
1289                 if ((unsigned long) wk == cookie) {
1290                         wk->timeout = jiffies;
1291                         found = true;
1292                         break;
1293                 }
1294         }
1295         mutex_unlock(&local->mtx);
1296
1297         if (!found)
1298                 return -ENOENT;
1299
1300         ieee80211_queue_work(&local->hw, &local->work_work);
1301
1302         return 0;
1303 }