1 /* 2 * Scanning implementation 3 * 4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.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 2013-2015 Intel Mobile Communications GmbH 10 * Copyright 2016-2017 Intel Deutschland GmbH 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17 #include <linux/if_arp.h> 18 #include <linux/etherdevice.h> 19 #include <linux/rtnetlink.h> 20 #include <net/sch_generic.h> 21 #include <linux/slab.h> 22 #include <linux/export.h> 23 #include <linux/random.h> 24 #include <net/mac80211.h> 25 26 #include "ieee80211_i.h" 27 #include "driver-ops.h" 28 #include "mesh.h" 29 30 #define IEEE80211_PROBE_DELAY (HZ / 33) 31 #define IEEE80211_CHANNEL_TIME (HZ / 33) 32 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9) 33 34 void ieee80211_rx_bss_put(struct ieee80211_local *local, 35 struct ieee80211_bss *bss) 36 { 37 if (!bss) 38 return; 39 cfg80211_put_bss(local->hw.wiphy, 40 container_of((void *)bss, struct cfg80211_bss, priv)); 41 } 42 43 static bool is_uapsd_supported(struct ieee802_11_elems *elems) 44 { 45 u8 qos_info; 46 47 if (elems->wmm_info && elems->wmm_info_len == 7 48 && elems->wmm_info[5] == 1) 49 qos_info = elems->wmm_info[6]; 50 else if (elems->wmm_param && elems->wmm_param_len == 24 51 && elems->wmm_param[5] == 1) 52 qos_info = elems->wmm_param[6]; 53 else 54 /* no valid wmm information or parameter element found */ 55 return false; 56 57 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; 58 } 59 60 struct ieee80211_bss * 61 ieee80211_bss_info_update(struct ieee80211_local *local, 62 struct ieee80211_rx_status *rx_status, 63 struct ieee80211_mgmt *mgmt, size_t len, 64 struct ieee802_11_elems *elems, 65 struct ieee80211_channel *channel) 66 { 67 bool beacon = ieee80211_is_beacon(mgmt->frame_control); 68 struct cfg80211_bss *cbss; 69 struct ieee80211_bss *bss; 70 int clen, srlen; 71 struct cfg80211_inform_bss bss_meta = { 72 .boottime_ns = rx_status->boottime_ns, 73 }; 74 bool signal_valid; 75 struct ieee80211_sub_if_data *scan_sdata; 76 77 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL) 78 bss_meta.signal = 0; /* invalid signal indication */ 79 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM)) 80 bss_meta.signal = rx_status->signal * 100; 81 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC)) 82 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal; 83 84 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20; 85 if (rx_status->bw == RATE_INFO_BW_5) 86 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5; 87 else if (rx_status->bw == RATE_INFO_BW_10) 88 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10; 89 90 bss_meta.chan = channel; 91 92 rcu_read_lock(); 93 scan_sdata = rcu_dereference(local->scan_sdata); 94 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION && 95 scan_sdata->vif.bss_conf.assoc && 96 ieee80211_have_rx_timestamp(rx_status)) { 97 bss_meta.parent_tsf = 98 ieee80211_calculate_rx_timestamp(local, rx_status, 99 len + FCS_LEN, 24); 100 ether_addr_copy(bss_meta.parent_bssid, 101 scan_sdata->vif.bss_conf.bssid); 102 } 103 rcu_read_unlock(); 104 105 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, 106 mgmt, len, GFP_ATOMIC); 107 if (!cbss) 108 return NULL; 109 /* In case the signal is invalid update the status */ 110 signal_valid = abs(channel->center_freq - cbss->channel->center_freq) 111 <= local->hw.wiphy->max_adj_channel_rssi_comp; 112 if (!signal_valid) 113 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL; 114 115 bss = (void *)cbss->priv; 116 117 if (beacon) 118 bss->device_ts_beacon = rx_status->device_timestamp; 119 else 120 bss->device_ts_presp = rx_status->device_timestamp; 121 122 if (elems->parse_error) { 123 if (beacon) 124 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; 125 else 126 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; 127 } else { 128 if (beacon) 129 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; 130 else 131 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; 132 } 133 134 /* save the ERP value so that it is available at association time */ 135 if (elems->erp_info && (!elems->parse_error || 136 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { 137 bss->erp_value = elems->erp_info[0]; 138 bss->has_erp_value = true; 139 if (!elems->parse_error) 140 bss->valid_data |= IEEE80211_BSS_VALID_ERP; 141 } 142 143 /* replace old supported rates if we get new values */ 144 if (!elems->parse_error || 145 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { 146 srlen = 0; 147 if (elems->supp_rates) { 148 clen = IEEE80211_MAX_SUPP_RATES; 149 if (clen > elems->supp_rates_len) 150 clen = elems->supp_rates_len; 151 memcpy(bss->supp_rates, elems->supp_rates, clen); 152 srlen += clen; 153 } 154 if (elems->ext_supp_rates) { 155 clen = IEEE80211_MAX_SUPP_RATES - srlen; 156 if (clen > elems->ext_supp_rates_len) 157 clen = elems->ext_supp_rates_len; 158 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, 159 clen); 160 srlen += clen; 161 } 162 if (srlen) { 163 bss->supp_rates_len = srlen; 164 if (!elems->parse_error) 165 bss->valid_data |= IEEE80211_BSS_VALID_RATES; 166 } 167 } 168 169 if (!elems->parse_error || 170 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { 171 bss->wmm_used = elems->wmm_param || elems->wmm_info; 172 bss->uapsd_supported = is_uapsd_supported(elems); 173 if (!elems->parse_error) 174 bss->valid_data |= IEEE80211_BSS_VALID_WMM; 175 } 176 177 if (beacon) { 178 struct ieee80211_supported_band *sband = 179 local->hw.wiphy->bands[rx_status->band]; 180 if (!(rx_status->encoding == RX_ENC_HT) && 181 !(rx_status->encoding == RX_ENC_VHT)) 182 bss->beacon_rate = 183 &sband->bitrates[rx_status->rate_idx]; 184 } 185 186 return bss; 187 } 188 189 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 190 u32 scan_flags, const u8 *da) 191 { 192 if (!sdata) 193 return false; 194 /* accept broadcast for OCE */ 195 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 196 is_broadcast_ether_addr(da)) 197 return true; 198 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 199 return true; 200 return ether_addr_equal(da, sdata->vif.addr); 201 } 202 203 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 204 { 205 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 206 struct ieee80211_sub_if_data *sdata1, *sdata2; 207 struct ieee80211_mgmt *mgmt = (void *)skb->data; 208 struct ieee80211_bss *bss; 209 u8 *elements; 210 struct ieee80211_channel *channel; 211 size_t baselen; 212 struct ieee802_11_elems elems; 213 214 if (skb->len < 24 || 215 (!ieee80211_is_probe_resp(mgmt->frame_control) && 216 !ieee80211_is_beacon(mgmt->frame_control))) 217 return; 218 219 sdata1 = rcu_dereference(local->scan_sdata); 220 sdata2 = rcu_dereference(local->sched_scan_sdata); 221 222 if (likely(!sdata1 && !sdata2)) 223 return; 224 225 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 226 struct cfg80211_scan_request *scan_req; 227 struct cfg80211_sched_scan_request *sched_scan_req; 228 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 229 230 scan_req = rcu_dereference(local->scan_req); 231 sched_scan_req = rcu_dereference(local->sched_scan_req); 232 233 if (scan_req) 234 scan_req_flags = scan_req->flags; 235 236 if (sched_scan_req) 237 sched_scan_req_flags = sched_scan_req->flags; 238 239 /* ignore ProbeResp to foreign address or non-bcast (OCE) 240 * unless scanning with randomised address 241 */ 242 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 243 mgmt->da) && 244 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 245 mgmt->da)) 246 return; 247 248 elements = mgmt->u.probe_resp.variable; 249 baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); 250 } else { 251 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); 252 elements = mgmt->u.beacon.variable; 253 } 254 255 if (baselen > skb->len) 256 return; 257 258 ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems); 259 260 channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); 261 262 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 263 return; 264 265 bss = ieee80211_bss_info_update(local, rx_status, 266 mgmt, skb->len, &elems, 267 channel); 268 if (bss) 269 ieee80211_rx_bss_put(local, bss); 270 } 271 272 static void 273 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 274 enum nl80211_bss_scan_width scan_width) 275 { 276 memset(chandef, 0, sizeof(*chandef)); 277 switch (scan_width) { 278 case NL80211_BSS_CHAN_WIDTH_5: 279 chandef->width = NL80211_CHAN_WIDTH_5; 280 break; 281 case NL80211_BSS_CHAN_WIDTH_10: 282 chandef->width = NL80211_CHAN_WIDTH_10; 283 break; 284 default: 285 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 286 break; 287 } 288 } 289 290 /* return false if no more work */ 291 static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) 292 { 293 struct cfg80211_scan_request *req; 294 struct cfg80211_chan_def chandef; 295 u8 bands_used = 0; 296 int i, ielen, n_chans; 297 u32 flags = 0; 298 299 req = rcu_dereference_protected(local->scan_req, 300 lockdep_is_held(&local->mtx)); 301 302 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 303 return false; 304 305 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 306 for (i = 0; i < req->n_channels; i++) { 307 local->hw_scan_req->req.channels[i] = req->channels[i]; 308 bands_used |= BIT(req->channels[i]->band); 309 } 310 311 n_chans = req->n_channels; 312 } else { 313 do { 314 if (local->hw_scan_band == NUM_NL80211_BANDS) 315 return false; 316 317 n_chans = 0; 318 319 for (i = 0; i < req->n_channels; i++) { 320 if (req->channels[i]->band != 321 local->hw_scan_band) 322 continue; 323 local->hw_scan_req->req.channels[n_chans] = 324 req->channels[i]; 325 n_chans++; 326 bands_used |= BIT(req->channels[i]->band); 327 } 328 329 local->hw_scan_band++; 330 } while (!n_chans); 331 } 332 333 local->hw_scan_req->req.n_channels = n_chans; 334 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 335 336 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 337 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 338 339 ielen = ieee80211_build_preq_ies(local, 340 (u8 *)local->hw_scan_req->req.ie, 341 local->hw_scan_ies_bufsize, 342 &local->hw_scan_req->ies, 343 req->ie, req->ie_len, 344 bands_used, req->rates, &chandef, 345 flags); 346 local->hw_scan_req->req.ie_len = ielen; 347 local->hw_scan_req->req.no_cck = req->no_cck; 348 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 349 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 350 req->mac_addr_mask); 351 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 352 353 return true; 354 } 355 356 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 357 { 358 struct ieee80211_local *local = hw_to_local(hw); 359 bool hw_scan = local->ops->hw_scan; 360 bool was_scanning = local->scanning; 361 struct cfg80211_scan_request *scan_req; 362 struct ieee80211_sub_if_data *scan_sdata; 363 struct ieee80211_sub_if_data *sdata; 364 365 lockdep_assert_held(&local->mtx); 366 367 /* 368 * It's ok to abort a not-yet-running scan (that 369 * we have one at all will be verified by checking 370 * local->scan_req next), but not to complete it 371 * successfully. 372 */ 373 if (WARN_ON(!local->scanning && !aborted)) 374 aborted = true; 375 376 if (WARN_ON(!local->scan_req)) 377 return; 378 379 if (hw_scan && !aborted && 380 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 381 ieee80211_prep_hw_scan(local)) { 382 int rc; 383 384 rc = drv_hw_scan(local, 385 rcu_dereference_protected(local->scan_sdata, 386 lockdep_is_held(&local->mtx)), 387 local->hw_scan_req); 388 389 if (rc == 0) 390 return; 391 392 /* HW scan failed and is going to be reported as aborted, 393 * so clear old scan info. 394 */ 395 memset(&local->scan_info, 0, sizeof(local->scan_info)); 396 aborted = true; 397 } 398 399 kfree(local->hw_scan_req); 400 local->hw_scan_req = NULL; 401 402 scan_req = rcu_dereference_protected(local->scan_req, 403 lockdep_is_held(&local->mtx)); 404 405 if (scan_req != local->int_scan_req) { 406 local->scan_info.aborted = aborted; 407 cfg80211_scan_done(scan_req, &local->scan_info); 408 } 409 RCU_INIT_POINTER(local->scan_req, NULL); 410 411 scan_sdata = rcu_dereference_protected(local->scan_sdata, 412 lockdep_is_held(&local->mtx)); 413 RCU_INIT_POINTER(local->scan_sdata, NULL); 414 415 local->scanning = 0; 416 local->scan_chandef.chan = NULL; 417 418 /* Set power back to normal operating levels. */ 419 ieee80211_hw_config(local, 0); 420 421 if (!hw_scan) { 422 ieee80211_configure_filter(local); 423 drv_sw_scan_complete(local, scan_sdata); 424 ieee80211_offchannel_return(local); 425 } 426 427 ieee80211_recalc_idle(local); 428 429 ieee80211_mlme_notify_scan_completed(local); 430 ieee80211_ibss_notify_scan_completed(local); 431 432 /* Requeue all the work that might have been ignored while 433 * the scan was in progress; if there was none this will 434 * just be a no-op for the particular interface. 435 */ 436 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 437 if (ieee80211_sdata_running(sdata)) 438 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 439 } 440 441 if (was_scanning) 442 ieee80211_start_next_roc(local); 443 } 444 445 void ieee80211_scan_completed(struct ieee80211_hw *hw, 446 struct cfg80211_scan_info *info) 447 { 448 struct ieee80211_local *local = hw_to_local(hw); 449 450 trace_api_scan_completed(local, info->aborted); 451 452 set_bit(SCAN_COMPLETED, &local->scanning); 453 if (info->aborted) 454 set_bit(SCAN_ABORTED, &local->scanning); 455 456 memcpy(&local->scan_info, info, sizeof(*info)); 457 458 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 459 } 460 EXPORT_SYMBOL(ieee80211_scan_completed); 461 462 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 463 struct ieee80211_sub_if_data *sdata) 464 { 465 /* Software scan is not supported in multi-channel cases */ 466 if (local->use_chanctx) 467 return -EOPNOTSUPP; 468 469 /* 470 * Hardware/driver doesn't support hw_scan, so use software 471 * scanning instead. First send a nullfunc frame with power save 472 * bit on so that AP will buffer the frames for us while we are not 473 * listening, then send probe requests to each channel and wait for 474 * the responses. After all channels are scanned, tune back to the 475 * original channel and send a nullfunc frame with power save bit 476 * off to trigger the AP to send us all the buffered frames. 477 * 478 * Note that while local->sw_scanning is true everything else but 479 * nullfunc frames and probe requests will be dropped in 480 * ieee80211_tx_h_check_assoc(). 481 */ 482 drv_sw_scan_start(local, sdata, local->scan_addr); 483 484 local->leave_oper_channel_time = jiffies; 485 local->next_scan_state = SCAN_DECISION; 486 local->scan_channel_idx = 0; 487 488 ieee80211_offchannel_stop_vifs(local); 489 490 /* ensure nullfunc is transmitted before leaving operating channel */ 491 ieee80211_flush_queues(local, NULL, false); 492 493 ieee80211_configure_filter(local); 494 495 /* We need to set power level at maximum rate for scanning. */ 496 ieee80211_hw_config(local, 0); 497 498 ieee80211_queue_delayed_work(&local->hw, 499 &local->scan_work, 0); 500 501 return 0; 502 } 503 504 static bool ieee80211_can_scan(struct ieee80211_local *local, 505 struct ieee80211_sub_if_data *sdata) 506 { 507 if (ieee80211_is_radar_required(local)) 508 return false; 509 510 if (!list_empty(&local->roc_list)) 511 return false; 512 513 if (sdata->vif.type == NL80211_IFTYPE_STATION && 514 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 515 return false; 516 517 return true; 518 } 519 520 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 521 { 522 lockdep_assert_held(&local->mtx); 523 524 if (!local->scan_req || local->scanning) 525 return; 526 527 if (!ieee80211_can_scan(local, 528 rcu_dereference_protected( 529 local->scan_sdata, 530 lockdep_is_held(&local->mtx)))) 531 return; 532 533 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 534 round_jiffies_relative(0)); 535 } 536 537 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 538 const u8 *src, const u8 *dst, 539 const u8 *ssid, size_t ssid_len, 540 const u8 *ie, size_t ie_len, 541 u32 ratemask, u32 flags, u32 tx_flags, 542 struct ieee80211_channel *channel) 543 { 544 struct sk_buff *skb; 545 u32 txdata_flags = 0; 546 547 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 548 ssid, ssid_len, 549 ie, ie_len, flags); 550 551 if (skb) { 552 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 553 struct ieee80211_hdr *hdr = (void *)skb->data; 554 u16 sn = get_random_u32(); 555 556 txdata_flags |= IEEE80211_TX_NO_SEQNO; 557 hdr->seq_ctrl = 558 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 559 } 560 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 561 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band, 562 txdata_flags); 563 } 564 } 565 566 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 567 unsigned long *next_delay) 568 { 569 int i; 570 struct ieee80211_sub_if_data *sdata; 571 struct cfg80211_scan_request *scan_req; 572 enum nl80211_band band = local->hw.conf.chandef.chan->band; 573 u32 flags = 0, tx_flags; 574 575 scan_req = rcu_dereference_protected(local->scan_req, 576 lockdep_is_held(&local->mtx)); 577 578 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 579 if (scan_req->no_cck) 580 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 581 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 582 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 583 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 584 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 585 586 sdata = rcu_dereference_protected(local->scan_sdata, 587 lockdep_is_held(&local->mtx)); 588 589 for (i = 0; i < scan_req->n_ssids; i++) 590 ieee80211_send_scan_probe_req( 591 sdata, local->scan_addr, scan_req->bssid, 592 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 593 scan_req->ie, scan_req->ie_len, 594 scan_req->rates[band], flags, 595 tx_flags, local->hw.conf.chandef.chan); 596 597 /* 598 * After sending probe requests, wait for probe responses 599 * on the channel. 600 */ 601 *next_delay = IEEE80211_CHANNEL_TIME; 602 local->next_scan_state = SCAN_DECISION; 603 } 604 605 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 606 struct cfg80211_scan_request *req) 607 { 608 struct ieee80211_local *local = sdata->local; 609 int rc; 610 611 lockdep_assert_held(&local->mtx); 612 613 if (local->scan_req || ieee80211_is_radar_required(local)) 614 return -EBUSY; 615 616 if (!ieee80211_can_scan(local, sdata)) { 617 /* wait for the work to finish/time out */ 618 rcu_assign_pointer(local->scan_req, req); 619 rcu_assign_pointer(local->scan_sdata, sdata); 620 return 0; 621 } 622 623 if (local->ops->hw_scan) { 624 u8 *ies; 625 626 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 627 628 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 629 int i, n_bands = 0; 630 u8 bands_counted = 0; 631 632 for (i = 0; i < req->n_channels; i++) { 633 if (bands_counted & BIT(req->channels[i]->band)) 634 continue; 635 bands_counted |= BIT(req->channels[i]->band); 636 n_bands++; 637 } 638 639 local->hw_scan_ies_bufsize *= n_bands; 640 } 641 642 local->hw_scan_req = kmalloc( 643 sizeof(*local->hw_scan_req) + 644 req->n_channels * sizeof(req->channels[0]) + 645 local->hw_scan_ies_bufsize, GFP_KERNEL); 646 if (!local->hw_scan_req) 647 return -ENOMEM; 648 649 local->hw_scan_req->req.ssids = req->ssids; 650 local->hw_scan_req->req.n_ssids = req->n_ssids; 651 ies = (u8 *)local->hw_scan_req + 652 sizeof(*local->hw_scan_req) + 653 req->n_channels * sizeof(req->channels[0]); 654 local->hw_scan_req->req.ie = ies; 655 local->hw_scan_req->req.flags = req->flags; 656 eth_broadcast_addr(local->hw_scan_req->req.bssid); 657 local->hw_scan_req->req.duration = req->duration; 658 local->hw_scan_req->req.duration_mandatory = 659 req->duration_mandatory; 660 661 local->hw_scan_band = 0; 662 663 /* 664 * After allocating local->hw_scan_req, we must 665 * go through until ieee80211_prep_hw_scan(), so 666 * anything that might be changed here and leave 667 * this function early must not go after this 668 * allocation. 669 */ 670 } 671 672 rcu_assign_pointer(local->scan_req, req); 673 rcu_assign_pointer(local->scan_sdata, sdata); 674 675 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 676 get_random_mask_addr(local->scan_addr, 677 req->mac_addr, 678 req->mac_addr_mask); 679 else 680 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 681 682 if (local->ops->hw_scan) { 683 __set_bit(SCAN_HW_SCANNING, &local->scanning); 684 } else if ((req->n_channels == 1) && 685 (req->channels[0] == local->_oper_chandef.chan)) { 686 /* 687 * If we are scanning only on the operating channel 688 * then we do not need to stop normal activities 689 */ 690 unsigned long next_delay; 691 692 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 693 694 ieee80211_recalc_idle(local); 695 696 /* Notify driver scan is starting, keep order of operations 697 * same as normal software scan, in case that matters. */ 698 drv_sw_scan_start(local, sdata, local->scan_addr); 699 700 ieee80211_configure_filter(local); /* accept probe-responses */ 701 702 /* We need to ensure power level is at max for scanning. */ 703 ieee80211_hw_config(local, 0); 704 705 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 706 IEEE80211_CHAN_RADAR)) || 707 !req->n_ssids) { 708 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 709 } else { 710 ieee80211_scan_state_send_probe(local, &next_delay); 711 next_delay = IEEE80211_CHANNEL_TIME; 712 } 713 714 /* Now, just wait a bit and we are all done! */ 715 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 716 next_delay); 717 return 0; 718 } else { 719 /* Do normal software scan */ 720 __set_bit(SCAN_SW_SCANNING, &local->scanning); 721 } 722 723 ieee80211_recalc_idle(local); 724 725 if (local->ops->hw_scan) { 726 WARN_ON(!ieee80211_prep_hw_scan(local)); 727 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 728 } else { 729 rc = ieee80211_start_sw_scan(local, sdata); 730 } 731 732 if (rc) { 733 kfree(local->hw_scan_req); 734 local->hw_scan_req = NULL; 735 local->scanning = 0; 736 737 ieee80211_recalc_idle(local); 738 739 local->scan_req = NULL; 740 RCU_INIT_POINTER(local->scan_sdata, NULL); 741 } 742 743 return rc; 744 } 745 746 static unsigned long 747 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 748 { 749 /* 750 * TODO: channel switching also consumes quite some time, 751 * add that delay as well to get a better estimation 752 */ 753 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 754 return IEEE80211_PASSIVE_CHANNEL_TIME; 755 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 756 } 757 758 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 759 unsigned long *next_delay) 760 { 761 bool associated = false; 762 bool tx_empty = true; 763 bool bad_latency; 764 struct ieee80211_sub_if_data *sdata; 765 struct ieee80211_channel *next_chan; 766 enum mac80211_scan_state next_scan_state; 767 struct cfg80211_scan_request *scan_req; 768 769 /* 770 * check if at least one STA interface is associated, 771 * check if at least one STA interface has pending tx frames 772 * and grab the lowest used beacon interval 773 */ 774 mutex_lock(&local->iflist_mtx); 775 list_for_each_entry(sdata, &local->interfaces, list) { 776 if (!ieee80211_sdata_running(sdata)) 777 continue; 778 779 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 780 if (sdata->u.mgd.associated) { 781 associated = true; 782 783 if (!qdisc_all_tx_empty(sdata->dev)) { 784 tx_empty = false; 785 break; 786 } 787 } 788 } 789 } 790 mutex_unlock(&local->iflist_mtx); 791 792 scan_req = rcu_dereference_protected(local->scan_req, 793 lockdep_is_held(&local->mtx)); 794 795 next_chan = scan_req->channels[local->scan_channel_idx]; 796 797 /* 798 * we're currently scanning a different channel, let's 799 * see if we can scan another channel without interfering 800 * with the current traffic situation. 801 * 802 * Keep good latency, do not stay off-channel more than 125 ms. 803 */ 804 805 bad_latency = time_after(jiffies + 806 ieee80211_scan_get_channel_time(next_chan), 807 local->leave_oper_channel_time + HZ / 8); 808 809 if (associated && !tx_empty) { 810 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 811 next_scan_state = SCAN_ABORT; 812 else 813 next_scan_state = SCAN_SUSPEND; 814 } else if (associated && bad_latency) { 815 next_scan_state = SCAN_SUSPEND; 816 } else { 817 next_scan_state = SCAN_SET_CHANNEL; 818 } 819 820 local->next_scan_state = next_scan_state; 821 822 *next_delay = 0; 823 } 824 825 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 826 unsigned long *next_delay) 827 { 828 int skip; 829 struct ieee80211_channel *chan; 830 enum nl80211_bss_scan_width oper_scan_width; 831 struct cfg80211_scan_request *scan_req; 832 833 scan_req = rcu_dereference_protected(local->scan_req, 834 lockdep_is_held(&local->mtx)); 835 836 skip = 0; 837 chan = scan_req->channels[local->scan_channel_idx]; 838 839 local->scan_chandef.chan = chan; 840 local->scan_chandef.center_freq1 = chan->center_freq; 841 local->scan_chandef.center_freq2 = 0; 842 switch (scan_req->scan_width) { 843 case NL80211_BSS_CHAN_WIDTH_5: 844 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 845 break; 846 case NL80211_BSS_CHAN_WIDTH_10: 847 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 848 break; 849 case NL80211_BSS_CHAN_WIDTH_20: 850 /* If scanning on oper channel, use whatever channel-type 851 * is currently in use. 852 */ 853 oper_scan_width = cfg80211_chandef_to_scan_width( 854 &local->_oper_chandef); 855 if (chan == local->_oper_chandef.chan && 856 oper_scan_width == scan_req->scan_width) 857 local->scan_chandef = local->_oper_chandef; 858 else 859 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 860 break; 861 } 862 863 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 864 skip = 1; 865 866 /* advance state machine to next channel/band */ 867 local->scan_channel_idx++; 868 869 if (skip) { 870 /* if we skip this channel return to the decision state */ 871 local->next_scan_state = SCAN_DECISION; 872 return; 873 } 874 875 /* 876 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 877 * (which unfortunately doesn't say _why_ step a) is done, 878 * but it waits for the probe delay or until a frame is 879 * received - and the received frame would update the NAV). 880 * For now, we do not support waiting until a frame is 881 * received. 882 * 883 * In any case, it is not necessary for a passive scan. 884 */ 885 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 886 !scan_req->n_ssids) { 887 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 888 local->next_scan_state = SCAN_DECISION; 889 return; 890 } 891 892 /* active scan, send probes */ 893 *next_delay = IEEE80211_PROBE_DELAY; 894 local->next_scan_state = SCAN_SEND_PROBE; 895 } 896 897 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 898 unsigned long *next_delay) 899 { 900 /* switch back to the operating channel */ 901 local->scan_chandef.chan = NULL; 902 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 903 904 /* disable PS */ 905 ieee80211_offchannel_return(local); 906 907 *next_delay = HZ / 5; 908 /* afterwards, resume scan & go to next channel */ 909 local->next_scan_state = SCAN_RESUME; 910 } 911 912 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 913 unsigned long *next_delay) 914 { 915 ieee80211_offchannel_stop_vifs(local); 916 917 if (local->ops->flush) { 918 ieee80211_flush_queues(local, NULL, false); 919 *next_delay = 0; 920 } else 921 *next_delay = HZ / 10; 922 923 /* remember when we left the operating channel */ 924 local->leave_oper_channel_time = jiffies; 925 926 /* advance to the next channel to be scanned */ 927 local->next_scan_state = SCAN_SET_CHANNEL; 928 } 929 930 void ieee80211_scan_work(struct work_struct *work) 931 { 932 struct ieee80211_local *local = 933 container_of(work, struct ieee80211_local, scan_work.work); 934 struct ieee80211_sub_if_data *sdata; 935 struct cfg80211_scan_request *scan_req; 936 unsigned long next_delay = 0; 937 bool aborted; 938 939 mutex_lock(&local->mtx); 940 941 if (!ieee80211_can_run_worker(local)) { 942 aborted = true; 943 goto out_complete; 944 } 945 946 sdata = rcu_dereference_protected(local->scan_sdata, 947 lockdep_is_held(&local->mtx)); 948 scan_req = rcu_dereference_protected(local->scan_req, 949 lockdep_is_held(&local->mtx)); 950 951 /* When scanning on-channel, the first-callback means completed. */ 952 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 953 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 954 goto out_complete; 955 } 956 957 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 958 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 959 goto out_complete; 960 } 961 962 if (!sdata || !scan_req) 963 goto out; 964 965 if (!local->scanning) { 966 int rc; 967 968 RCU_INIT_POINTER(local->scan_req, NULL); 969 RCU_INIT_POINTER(local->scan_sdata, NULL); 970 971 rc = __ieee80211_start_scan(sdata, scan_req); 972 if (rc) { 973 /* need to complete scan in cfg80211 */ 974 rcu_assign_pointer(local->scan_req, scan_req); 975 aborted = true; 976 goto out_complete; 977 } else 978 goto out; 979 } 980 981 /* 982 * as long as no delay is required advance immediately 983 * without scheduling a new work 984 */ 985 do { 986 if (!ieee80211_sdata_running(sdata)) { 987 aborted = true; 988 goto out_complete; 989 } 990 991 switch (local->next_scan_state) { 992 case SCAN_DECISION: 993 /* if no more bands/channels left, complete scan */ 994 if (local->scan_channel_idx >= scan_req->n_channels) { 995 aborted = false; 996 goto out_complete; 997 } 998 ieee80211_scan_state_decision(local, &next_delay); 999 break; 1000 case SCAN_SET_CHANNEL: 1001 ieee80211_scan_state_set_channel(local, &next_delay); 1002 break; 1003 case SCAN_SEND_PROBE: 1004 ieee80211_scan_state_send_probe(local, &next_delay); 1005 break; 1006 case SCAN_SUSPEND: 1007 ieee80211_scan_state_suspend(local, &next_delay); 1008 break; 1009 case SCAN_RESUME: 1010 ieee80211_scan_state_resume(local, &next_delay); 1011 break; 1012 case SCAN_ABORT: 1013 aborted = true; 1014 goto out_complete; 1015 } 1016 } while (next_delay == 0); 1017 1018 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); 1019 goto out; 1020 1021 out_complete: 1022 __ieee80211_scan_completed(&local->hw, aborted); 1023 out: 1024 mutex_unlock(&local->mtx); 1025 } 1026 1027 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1028 struct cfg80211_scan_request *req) 1029 { 1030 int res; 1031 1032 mutex_lock(&sdata->local->mtx); 1033 res = __ieee80211_start_scan(sdata, req); 1034 mutex_unlock(&sdata->local->mtx); 1035 1036 return res; 1037 } 1038 1039 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1040 const u8 *ssid, u8 ssid_len, 1041 struct ieee80211_channel **channels, 1042 unsigned int n_channels, 1043 enum nl80211_bss_scan_width scan_width) 1044 { 1045 struct ieee80211_local *local = sdata->local; 1046 int ret = -EBUSY, i, n_ch = 0; 1047 enum nl80211_band band; 1048 1049 mutex_lock(&local->mtx); 1050 1051 /* busy scanning */ 1052 if (local->scan_req) 1053 goto unlock; 1054 1055 /* fill internal scan request */ 1056 if (!channels) { 1057 int max_n; 1058 1059 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1060 if (!local->hw.wiphy->bands[band]) 1061 continue; 1062 1063 max_n = local->hw.wiphy->bands[band]->n_channels; 1064 for (i = 0; i < max_n; i++) { 1065 struct ieee80211_channel *tmp_ch = 1066 &local->hw.wiphy->bands[band]->channels[i]; 1067 1068 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1069 IEEE80211_CHAN_DISABLED)) 1070 continue; 1071 1072 local->int_scan_req->channels[n_ch] = tmp_ch; 1073 n_ch++; 1074 } 1075 } 1076 1077 if (WARN_ON_ONCE(n_ch == 0)) 1078 goto unlock; 1079 1080 local->int_scan_req->n_channels = n_ch; 1081 } else { 1082 for (i = 0; i < n_channels; i++) { 1083 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1084 IEEE80211_CHAN_DISABLED)) 1085 continue; 1086 1087 local->int_scan_req->channels[n_ch] = channels[i]; 1088 n_ch++; 1089 } 1090 1091 if (WARN_ON_ONCE(n_ch == 0)) 1092 goto unlock; 1093 1094 local->int_scan_req->n_channels = n_ch; 1095 } 1096 1097 local->int_scan_req->ssids = &local->scan_ssid; 1098 local->int_scan_req->n_ssids = 1; 1099 local->int_scan_req->scan_width = scan_width; 1100 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1101 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1102 1103 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1104 unlock: 1105 mutex_unlock(&local->mtx); 1106 return ret; 1107 } 1108 1109 /* 1110 * Only call this function when a scan can't be queued -- under RTNL. 1111 */ 1112 void ieee80211_scan_cancel(struct ieee80211_local *local) 1113 { 1114 /* 1115 * We are canceling software scan, or deferred scan that was not 1116 * yet really started (see __ieee80211_start_scan ). 1117 * 1118 * Regarding hardware scan: 1119 * - we can not call __ieee80211_scan_completed() as when 1120 * SCAN_HW_SCANNING bit is set this function change 1121 * local->hw_scan_req to operate on 5G band, what race with 1122 * driver which can use local->hw_scan_req 1123 * 1124 * - we can not cancel scan_work since driver can schedule it 1125 * by ieee80211_scan_completed(..., true) to finish scan 1126 * 1127 * Hence we only call the cancel_hw_scan() callback, but the low-level 1128 * driver is still responsible for calling ieee80211_scan_completed() 1129 * after the scan was completed/aborted. 1130 */ 1131 1132 mutex_lock(&local->mtx); 1133 if (!local->scan_req) 1134 goto out; 1135 1136 /* 1137 * We have a scan running and the driver already reported completion, 1138 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1139 * cancelled. 1140 */ 1141 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1142 test_bit(SCAN_COMPLETED, &local->scanning)) { 1143 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1144 goto out; 1145 } 1146 1147 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1148 /* 1149 * Make sure that __ieee80211_scan_completed doesn't trigger a 1150 * scan on another band. 1151 */ 1152 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1153 if (local->ops->cancel_hw_scan) 1154 drv_cancel_hw_scan(local, 1155 rcu_dereference_protected(local->scan_sdata, 1156 lockdep_is_held(&local->mtx))); 1157 goto out; 1158 } 1159 1160 /* 1161 * If the work is currently running, it must be blocked on 1162 * the mutex, but we'll set scan_sdata = NULL and it'll 1163 * simply exit once it acquires the mutex. 1164 */ 1165 cancel_delayed_work(&local->scan_work); 1166 /* and clean up */ 1167 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1168 __ieee80211_scan_completed(&local->hw, true); 1169 out: 1170 mutex_unlock(&local->mtx); 1171 } 1172 1173 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1174 struct cfg80211_sched_scan_request *req) 1175 { 1176 struct ieee80211_local *local = sdata->local; 1177 struct ieee80211_scan_ies sched_scan_ies = {}; 1178 struct cfg80211_chan_def chandef; 1179 int ret, i, iebufsz, num_bands = 0; 1180 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1181 u8 bands_used = 0; 1182 u8 *ie; 1183 u32 flags = 0; 1184 1185 iebufsz = local->scan_ies_len + req->ie_len; 1186 1187 lockdep_assert_held(&local->mtx); 1188 1189 if (!local->ops->sched_scan_start) 1190 return -ENOTSUPP; 1191 1192 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1193 if (local->hw.wiphy->bands[i]) { 1194 bands_used |= BIT(i); 1195 rate_masks[i] = (u32) -1; 1196 num_bands++; 1197 } 1198 } 1199 1200 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1201 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1202 1203 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1204 if (!ie) { 1205 ret = -ENOMEM; 1206 goto out; 1207 } 1208 1209 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1210 1211 ieee80211_build_preq_ies(local, ie, num_bands * iebufsz, 1212 &sched_scan_ies, req->ie, 1213 req->ie_len, bands_used, rate_masks, &chandef, 1214 flags); 1215 1216 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1217 if (ret == 0) { 1218 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1219 rcu_assign_pointer(local->sched_scan_req, req); 1220 } 1221 1222 kfree(ie); 1223 1224 out: 1225 if (ret) { 1226 /* Clean in case of failure after HW restart or upon resume. */ 1227 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1228 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1229 } 1230 1231 return ret; 1232 } 1233 1234 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1235 struct cfg80211_sched_scan_request *req) 1236 { 1237 struct ieee80211_local *local = sdata->local; 1238 int ret; 1239 1240 mutex_lock(&local->mtx); 1241 1242 if (rcu_access_pointer(local->sched_scan_sdata)) { 1243 mutex_unlock(&local->mtx); 1244 return -EBUSY; 1245 } 1246 1247 ret = __ieee80211_request_sched_scan_start(sdata, req); 1248 1249 mutex_unlock(&local->mtx); 1250 return ret; 1251 } 1252 1253 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1254 { 1255 struct ieee80211_sub_if_data *sched_scan_sdata; 1256 int ret = -ENOENT; 1257 1258 mutex_lock(&local->mtx); 1259 1260 if (!local->ops->sched_scan_stop) { 1261 ret = -ENOTSUPP; 1262 goto out; 1263 } 1264 1265 /* We don't want to restart sched scan anymore. */ 1266 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1267 1268 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1269 lockdep_is_held(&local->mtx)); 1270 if (sched_scan_sdata) { 1271 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1272 if (!ret) 1273 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1274 } 1275 out: 1276 mutex_unlock(&local->mtx); 1277 1278 return ret; 1279 } 1280 1281 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1282 { 1283 struct ieee80211_local *local = hw_to_local(hw); 1284 1285 trace_api_sched_scan_results(local); 1286 1287 cfg80211_sched_scan_results(hw->wiphy, 0); 1288 } 1289 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1290 1291 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1292 { 1293 mutex_lock(&local->mtx); 1294 1295 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1296 mutex_unlock(&local->mtx); 1297 return; 1298 } 1299 1300 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1301 1302 /* If sched scan was aborted by the driver. */ 1303 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1304 1305 mutex_unlock(&local->mtx); 1306 1307 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1308 } 1309 1310 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1311 { 1312 struct ieee80211_local *local = 1313 container_of(work, struct ieee80211_local, 1314 sched_scan_stopped_work); 1315 1316 ieee80211_sched_scan_end(local); 1317 } 1318 1319 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1320 { 1321 struct ieee80211_local *local = hw_to_local(hw); 1322 1323 trace_api_sched_scan_stopped(local); 1324 1325 /* 1326 * this shouldn't really happen, so for simplicity 1327 * simply ignore it, and let mac80211 reconfigure 1328 * the sched scan later on. 1329 */ 1330 if (local->in_reconfig) 1331 return; 1332 1333 schedule_work(&local->sched_scan_stopped_work); 1334 } 1335 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1336