1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Scanning implementation 4 * 5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 6 * Copyright 2004, Instant802 Networks, Inc. 7 * Copyright 2005, Devicescape Software, Inc. 8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 10 * Copyright 2013-2015 Intel Mobile Communications GmbH 11 * Copyright 2016-2017 Intel Deutschland GmbH 12 * Copyright (C) 2018-2020 Intel Corporation 13 */ 14 15 #include <linux/if_arp.h> 16 #include <linux/etherdevice.h> 17 #include <linux/rtnetlink.h> 18 #include <net/sch_generic.h> 19 #include <linux/slab.h> 20 #include <linux/export.h> 21 #include <linux/random.h> 22 #include <net/mac80211.h> 23 24 #include "ieee80211_i.h" 25 #include "driver-ops.h" 26 #include "mesh.h" 27 28 #define IEEE80211_PROBE_DELAY (HZ / 33) 29 #define IEEE80211_CHANNEL_TIME (HZ / 33) 30 #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9) 31 32 void ieee80211_rx_bss_put(struct ieee80211_local *local, 33 struct ieee80211_bss *bss) 34 { 35 if (!bss) 36 return; 37 cfg80211_put_bss(local->hw.wiphy, 38 container_of((void *)bss, struct cfg80211_bss, priv)); 39 } 40 41 static bool is_uapsd_supported(struct ieee802_11_elems *elems) 42 { 43 u8 qos_info; 44 45 if (elems->wmm_info && elems->wmm_info_len == 7 46 && elems->wmm_info[5] == 1) 47 qos_info = elems->wmm_info[6]; 48 else if (elems->wmm_param && elems->wmm_param_len == 24 49 && elems->wmm_param[5] == 1) 50 qos_info = elems->wmm_param[6]; 51 else 52 /* no valid wmm information or parameter element found */ 53 return false; 54 55 return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; 56 } 57 58 static void 59 ieee80211_update_bss_from_elems(struct ieee80211_local *local, 60 struct ieee80211_bss *bss, 61 struct ieee802_11_elems *elems, 62 struct ieee80211_rx_status *rx_status, 63 bool beacon) 64 { 65 int clen, srlen; 66 67 if (beacon) 68 bss->device_ts_beacon = rx_status->device_timestamp; 69 else 70 bss->device_ts_presp = rx_status->device_timestamp; 71 72 if (elems->parse_error) { 73 if (beacon) 74 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; 75 else 76 bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; 77 } else { 78 if (beacon) 79 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; 80 else 81 bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; 82 } 83 84 /* save the ERP value so that it is available at association time */ 85 if (elems->erp_info && (!elems->parse_error || 86 !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { 87 bss->erp_value = elems->erp_info[0]; 88 bss->has_erp_value = true; 89 if (!elems->parse_error) 90 bss->valid_data |= IEEE80211_BSS_VALID_ERP; 91 } 92 93 /* replace old supported rates if we get new values */ 94 if (!elems->parse_error || 95 !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { 96 srlen = 0; 97 if (elems->supp_rates) { 98 clen = IEEE80211_MAX_SUPP_RATES; 99 if (clen > elems->supp_rates_len) 100 clen = elems->supp_rates_len; 101 memcpy(bss->supp_rates, elems->supp_rates, clen); 102 srlen += clen; 103 } 104 if (elems->ext_supp_rates) { 105 clen = IEEE80211_MAX_SUPP_RATES - srlen; 106 if (clen > elems->ext_supp_rates_len) 107 clen = elems->ext_supp_rates_len; 108 memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, 109 clen); 110 srlen += clen; 111 } 112 if (srlen) { 113 bss->supp_rates_len = srlen; 114 if (!elems->parse_error) 115 bss->valid_data |= IEEE80211_BSS_VALID_RATES; 116 } 117 } 118 119 if (!elems->parse_error || 120 !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { 121 bss->wmm_used = elems->wmm_param || elems->wmm_info; 122 bss->uapsd_supported = is_uapsd_supported(elems); 123 if (!elems->parse_error) 124 bss->valid_data |= IEEE80211_BSS_VALID_WMM; 125 } 126 127 if (beacon) { 128 struct ieee80211_supported_band *sband = 129 local->hw.wiphy->bands[rx_status->band]; 130 if (!(rx_status->encoding == RX_ENC_HT) && 131 !(rx_status->encoding == RX_ENC_VHT)) 132 bss->beacon_rate = 133 &sband->bitrates[rx_status->rate_idx]; 134 } 135 136 if (elems->vht_cap_elem) 137 bss->vht_cap_info = 138 le32_to_cpu(elems->vht_cap_elem->vht_cap_info); 139 else 140 bss->vht_cap_info = 0; 141 } 142 143 struct ieee80211_bss * 144 ieee80211_bss_info_update(struct ieee80211_local *local, 145 struct ieee80211_rx_status *rx_status, 146 struct ieee80211_mgmt *mgmt, size_t len, 147 struct ieee80211_channel *channel) 148 { 149 bool beacon = ieee80211_is_beacon(mgmt->frame_control) || 150 ieee80211_is_s1g_beacon(mgmt->frame_control); 151 struct cfg80211_bss *cbss, *non_tx_cbss; 152 struct ieee80211_bss *bss, *non_tx_bss; 153 struct cfg80211_inform_bss bss_meta = { 154 .boottime_ns = rx_status->boottime_ns, 155 }; 156 bool signal_valid; 157 struct ieee80211_sub_if_data *scan_sdata; 158 struct ieee802_11_elems elems; 159 size_t baselen; 160 u8 *elements; 161 162 if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL) 163 bss_meta.signal = 0; /* invalid signal indication */ 164 else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM)) 165 bss_meta.signal = rx_status->signal * 100; 166 else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC)) 167 bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal; 168 169 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20; 170 if (rx_status->bw == RATE_INFO_BW_5) 171 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5; 172 else if (rx_status->bw == RATE_INFO_BW_10) 173 bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10; 174 175 bss_meta.chan = channel; 176 177 rcu_read_lock(); 178 scan_sdata = rcu_dereference(local->scan_sdata); 179 if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION && 180 scan_sdata->vif.bss_conf.assoc && 181 ieee80211_have_rx_timestamp(rx_status)) { 182 bss_meta.parent_tsf = 183 ieee80211_calculate_rx_timestamp(local, rx_status, 184 len + FCS_LEN, 24); 185 ether_addr_copy(bss_meta.parent_bssid, 186 scan_sdata->vif.bss_conf.bssid); 187 } 188 rcu_read_unlock(); 189 190 cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, 191 mgmt, len, GFP_ATOMIC); 192 if (!cbss) 193 return NULL; 194 195 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 196 elements = mgmt->u.probe_resp.variable; 197 baselen = offsetof(struct ieee80211_mgmt, 198 u.probe_resp.variable); 199 } else if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 200 struct ieee80211_ext *ext = (void *) mgmt; 201 202 baselen = offsetof(struct ieee80211_ext, u.s1g_beacon.variable); 203 elements = ext->u.s1g_beacon.variable; 204 } else { 205 baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); 206 elements = mgmt->u.beacon.variable; 207 } 208 209 if (baselen > len) 210 return NULL; 211 212 ieee802_11_parse_elems(elements, len - baselen, false, &elems, 213 mgmt->bssid, cbss->bssid); 214 215 /* In case the signal is invalid update the status */ 216 signal_valid = channel == cbss->channel; 217 if (!signal_valid) 218 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL; 219 220 bss = (void *)cbss->priv; 221 ieee80211_update_bss_from_elems(local, bss, &elems, rx_status, beacon); 222 223 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) { 224 non_tx_bss = (void *)non_tx_cbss->priv; 225 226 ieee80211_update_bss_from_elems(local, non_tx_bss, &elems, 227 rx_status, beacon); 228 } 229 230 return bss; 231 } 232 233 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 234 u32 scan_flags, const u8 *da) 235 { 236 if (!sdata) 237 return false; 238 /* accept broadcast for OCE */ 239 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 240 is_broadcast_ether_addr(da)) 241 return true; 242 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 243 return true; 244 return ether_addr_equal(da, sdata->vif.addr); 245 } 246 247 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 248 { 249 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 250 struct ieee80211_sub_if_data *sdata1, *sdata2; 251 struct ieee80211_mgmt *mgmt = (void *)skb->data; 252 struct ieee80211_bss *bss; 253 struct ieee80211_channel *channel; 254 255 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 256 if (skb->len < 15) 257 return; 258 } else if (skb->len < 24 || 259 (!ieee80211_is_probe_resp(mgmt->frame_control) && 260 !ieee80211_is_beacon(mgmt->frame_control))) 261 return; 262 263 sdata1 = rcu_dereference(local->scan_sdata); 264 sdata2 = rcu_dereference(local->sched_scan_sdata); 265 266 if (likely(!sdata1 && !sdata2)) 267 return; 268 269 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 270 struct cfg80211_scan_request *scan_req; 271 struct cfg80211_sched_scan_request *sched_scan_req; 272 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 273 274 scan_req = rcu_dereference(local->scan_req); 275 sched_scan_req = rcu_dereference(local->sched_scan_req); 276 277 if (scan_req) 278 scan_req_flags = scan_req->flags; 279 280 if (sched_scan_req) 281 sched_scan_req_flags = sched_scan_req->flags; 282 283 /* ignore ProbeResp to foreign address or non-bcast (OCE) 284 * unless scanning with randomised address 285 */ 286 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 287 mgmt->da) && 288 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 289 mgmt->da)) 290 return; 291 } 292 293 channel = ieee80211_get_channel_khz(local->hw.wiphy, 294 ieee80211_rx_status_to_khz(rx_status)); 295 296 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 297 return; 298 299 bss = ieee80211_bss_info_update(local, rx_status, 300 mgmt, skb->len, 301 channel); 302 if (bss) 303 ieee80211_rx_bss_put(local, bss); 304 } 305 306 static void 307 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 308 enum nl80211_bss_scan_width scan_width) 309 { 310 memset(chandef, 0, sizeof(*chandef)); 311 switch (scan_width) { 312 case NL80211_BSS_CHAN_WIDTH_5: 313 chandef->width = NL80211_CHAN_WIDTH_5; 314 break; 315 case NL80211_BSS_CHAN_WIDTH_10: 316 chandef->width = NL80211_CHAN_WIDTH_10; 317 break; 318 default: 319 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 320 break; 321 } 322 } 323 324 /* return false if no more work */ 325 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 326 { 327 struct ieee80211_local *local = sdata->local; 328 struct cfg80211_scan_request *req; 329 struct cfg80211_chan_def chandef; 330 u8 bands_used = 0; 331 int i, ielen, n_chans; 332 u32 flags = 0; 333 334 req = rcu_dereference_protected(local->scan_req, 335 lockdep_is_held(&local->mtx)); 336 337 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 338 return false; 339 340 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 341 for (i = 0; i < req->n_channels; i++) { 342 local->hw_scan_req->req.channels[i] = req->channels[i]; 343 bands_used |= BIT(req->channels[i]->band); 344 } 345 346 n_chans = req->n_channels; 347 } else { 348 do { 349 if (local->hw_scan_band == NUM_NL80211_BANDS) 350 return false; 351 352 n_chans = 0; 353 354 for (i = 0; i < req->n_channels; i++) { 355 if (req->channels[i]->band != 356 local->hw_scan_band) 357 continue; 358 local->hw_scan_req->req.channels[n_chans] = 359 req->channels[i]; 360 n_chans++; 361 bands_used |= BIT(req->channels[i]->band); 362 } 363 364 local->hw_scan_band++; 365 } while (!n_chans); 366 } 367 368 local->hw_scan_req->req.n_channels = n_chans; 369 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 370 371 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 372 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 373 374 ielen = ieee80211_build_preq_ies(sdata, 375 (u8 *)local->hw_scan_req->req.ie, 376 local->hw_scan_ies_bufsize, 377 &local->hw_scan_req->ies, 378 req->ie, req->ie_len, 379 bands_used, req->rates, &chandef, 380 flags); 381 local->hw_scan_req->req.ie_len = ielen; 382 local->hw_scan_req->req.no_cck = req->no_cck; 383 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 384 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 385 req->mac_addr_mask); 386 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 387 388 return true; 389 } 390 391 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 392 { 393 struct ieee80211_local *local = hw_to_local(hw); 394 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 395 bool was_scanning = local->scanning; 396 struct cfg80211_scan_request *scan_req; 397 struct ieee80211_sub_if_data *scan_sdata; 398 struct ieee80211_sub_if_data *sdata; 399 400 lockdep_assert_held(&local->mtx); 401 402 /* 403 * It's ok to abort a not-yet-running scan (that 404 * we have one at all will be verified by checking 405 * local->scan_req next), but not to complete it 406 * successfully. 407 */ 408 if (WARN_ON(!local->scanning && !aborted)) 409 aborted = true; 410 411 if (WARN_ON(!local->scan_req)) 412 return; 413 414 scan_sdata = rcu_dereference_protected(local->scan_sdata, 415 lockdep_is_held(&local->mtx)); 416 417 if (hw_scan && !aborted && 418 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 419 ieee80211_prep_hw_scan(scan_sdata)) { 420 int rc; 421 422 rc = drv_hw_scan(local, 423 rcu_dereference_protected(local->scan_sdata, 424 lockdep_is_held(&local->mtx)), 425 local->hw_scan_req); 426 427 if (rc == 0) 428 return; 429 430 /* HW scan failed and is going to be reported as aborted, 431 * so clear old scan info. 432 */ 433 memset(&local->scan_info, 0, sizeof(local->scan_info)); 434 aborted = true; 435 } 436 437 kfree(local->hw_scan_req); 438 local->hw_scan_req = NULL; 439 440 scan_req = rcu_dereference_protected(local->scan_req, 441 lockdep_is_held(&local->mtx)); 442 443 if (scan_req != local->int_scan_req) { 444 local->scan_info.aborted = aborted; 445 cfg80211_scan_done(scan_req, &local->scan_info); 446 } 447 RCU_INIT_POINTER(local->scan_req, NULL); 448 RCU_INIT_POINTER(local->scan_sdata, NULL); 449 450 local->scanning = 0; 451 local->scan_chandef.chan = NULL; 452 453 /* Set power back to normal operating levels. */ 454 ieee80211_hw_config(local, 0); 455 456 if (!hw_scan) { 457 ieee80211_configure_filter(local); 458 drv_sw_scan_complete(local, scan_sdata); 459 ieee80211_offchannel_return(local); 460 } 461 462 ieee80211_recalc_idle(local); 463 464 ieee80211_mlme_notify_scan_completed(local); 465 ieee80211_ibss_notify_scan_completed(local); 466 467 /* Requeue all the work that might have been ignored while 468 * the scan was in progress; if there was none this will 469 * just be a no-op for the particular interface. 470 */ 471 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 472 if (ieee80211_sdata_running(sdata)) 473 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 474 } 475 476 if (was_scanning) 477 ieee80211_start_next_roc(local); 478 } 479 480 void ieee80211_scan_completed(struct ieee80211_hw *hw, 481 struct cfg80211_scan_info *info) 482 { 483 struct ieee80211_local *local = hw_to_local(hw); 484 485 trace_api_scan_completed(local, info->aborted); 486 487 set_bit(SCAN_COMPLETED, &local->scanning); 488 if (info->aborted) 489 set_bit(SCAN_ABORTED, &local->scanning); 490 491 memcpy(&local->scan_info, info, sizeof(*info)); 492 493 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 494 } 495 EXPORT_SYMBOL(ieee80211_scan_completed); 496 497 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 498 struct ieee80211_sub_if_data *sdata) 499 { 500 /* Software scan is not supported in multi-channel cases */ 501 if (local->use_chanctx) 502 return -EOPNOTSUPP; 503 504 /* 505 * Hardware/driver doesn't support hw_scan, so use software 506 * scanning instead. First send a nullfunc frame with power save 507 * bit on so that AP will buffer the frames for us while we are not 508 * listening, then send probe requests to each channel and wait for 509 * the responses. After all channels are scanned, tune back to the 510 * original channel and send a nullfunc frame with power save bit 511 * off to trigger the AP to send us all the buffered frames. 512 * 513 * Note that while local->sw_scanning is true everything else but 514 * nullfunc frames and probe requests will be dropped in 515 * ieee80211_tx_h_check_assoc(). 516 */ 517 drv_sw_scan_start(local, sdata, local->scan_addr); 518 519 local->leave_oper_channel_time = jiffies; 520 local->next_scan_state = SCAN_DECISION; 521 local->scan_channel_idx = 0; 522 523 ieee80211_offchannel_stop_vifs(local); 524 525 /* ensure nullfunc is transmitted before leaving operating channel */ 526 ieee80211_flush_queues(local, NULL, false); 527 528 ieee80211_configure_filter(local); 529 530 /* We need to set power level at maximum rate for scanning. */ 531 ieee80211_hw_config(local, 0); 532 533 ieee80211_queue_delayed_work(&local->hw, 534 &local->scan_work, 0); 535 536 return 0; 537 } 538 539 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 540 { 541 struct ieee80211_local *local = sdata->local; 542 struct ieee80211_sub_if_data *sdata_iter; 543 544 if (!ieee80211_is_radar_required(local)) 545 return true; 546 547 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 548 return false; 549 550 mutex_lock(&local->iflist_mtx); 551 list_for_each_entry(sdata_iter, &local->interfaces, list) { 552 if (sdata_iter->wdev.cac_started) { 553 mutex_unlock(&local->iflist_mtx); 554 return false; 555 } 556 } 557 mutex_unlock(&local->iflist_mtx); 558 559 return true; 560 } 561 562 static bool ieee80211_can_scan(struct ieee80211_local *local, 563 struct ieee80211_sub_if_data *sdata) 564 { 565 if (!__ieee80211_can_leave_ch(sdata)) 566 return false; 567 568 if (!list_empty(&local->roc_list)) 569 return false; 570 571 if (sdata->vif.type == NL80211_IFTYPE_STATION && 572 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 573 return false; 574 575 return true; 576 } 577 578 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 579 { 580 lockdep_assert_held(&local->mtx); 581 582 if (!local->scan_req || local->scanning) 583 return; 584 585 if (!ieee80211_can_scan(local, 586 rcu_dereference_protected( 587 local->scan_sdata, 588 lockdep_is_held(&local->mtx)))) 589 return; 590 591 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 592 round_jiffies_relative(0)); 593 } 594 595 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 596 const u8 *src, const u8 *dst, 597 const u8 *ssid, size_t ssid_len, 598 const u8 *ie, size_t ie_len, 599 u32 ratemask, u32 flags, u32 tx_flags, 600 struct ieee80211_channel *channel) 601 { 602 struct sk_buff *skb; 603 604 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 605 ssid, ssid_len, 606 ie, ie_len, flags); 607 608 if (skb) { 609 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 610 struct ieee80211_hdr *hdr = (void *)skb->data; 611 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 612 u16 sn = get_random_u32(); 613 614 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 615 hdr->seq_ctrl = 616 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 617 } 618 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 619 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 620 } 621 } 622 623 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 624 unsigned long *next_delay) 625 { 626 int i; 627 struct ieee80211_sub_if_data *sdata; 628 struct cfg80211_scan_request *scan_req; 629 enum nl80211_band band = local->hw.conf.chandef.chan->band; 630 u32 flags = 0, tx_flags; 631 632 scan_req = rcu_dereference_protected(local->scan_req, 633 lockdep_is_held(&local->mtx)); 634 635 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 636 if (scan_req->no_cck) 637 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 638 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 639 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 640 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 641 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 642 643 sdata = rcu_dereference_protected(local->scan_sdata, 644 lockdep_is_held(&local->mtx)); 645 646 for (i = 0; i < scan_req->n_ssids; i++) 647 ieee80211_send_scan_probe_req( 648 sdata, local->scan_addr, scan_req->bssid, 649 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 650 scan_req->ie, scan_req->ie_len, 651 scan_req->rates[band], flags, 652 tx_flags, local->hw.conf.chandef.chan); 653 654 /* 655 * After sending probe requests, wait for probe responses 656 * on the channel. 657 */ 658 *next_delay = IEEE80211_CHANNEL_TIME; 659 local->next_scan_state = SCAN_DECISION; 660 } 661 662 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 663 struct cfg80211_scan_request *req) 664 { 665 struct ieee80211_local *local = sdata->local; 666 bool hw_scan = local->ops->hw_scan; 667 int rc; 668 669 lockdep_assert_held(&local->mtx); 670 671 if (local->scan_req) 672 return -EBUSY; 673 674 if (!__ieee80211_can_leave_ch(sdata)) 675 return -EBUSY; 676 677 if (!ieee80211_can_scan(local, sdata)) { 678 /* wait for the work to finish/time out */ 679 rcu_assign_pointer(local->scan_req, req); 680 rcu_assign_pointer(local->scan_sdata, sdata); 681 return 0; 682 } 683 684 again: 685 if (hw_scan) { 686 u8 *ies; 687 688 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 689 690 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 691 int i, n_bands = 0; 692 u8 bands_counted = 0; 693 694 for (i = 0; i < req->n_channels; i++) { 695 if (bands_counted & BIT(req->channels[i]->band)) 696 continue; 697 bands_counted |= BIT(req->channels[i]->band); 698 n_bands++; 699 } 700 701 local->hw_scan_ies_bufsize *= n_bands; 702 } 703 704 local->hw_scan_req = kmalloc( 705 sizeof(*local->hw_scan_req) + 706 req->n_channels * sizeof(req->channels[0]) + 707 local->hw_scan_ies_bufsize, GFP_KERNEL); 708 if (!local->hw_scan_req) 709 return -ENOMEM; 710 711 local->hw_scan_req->req.ssids = req->ssids; 712 local->hw_scan_req->req.n_ssids = req->n_ssids; 713 ies = (u8 *)local->hw_scan_req + 714 sizeof(*local->hw_scan_req) + 715 req->n_channels * sizeof(req->channels[0]); 716 local->hw_scan_req->req.ie = ies; 717 local->hw_scan_req->req.flags = req->flags; 718 eth_broadcast_addr(local->hw_scan_req->req.bssid); 719 local->hw_scan_req->req.duration = req->duration; 720 local->hw_scan_req->req.duration_mandatory = 721 req->duration_mandatory; 722 723 local->hw_scan_band = 0; 724 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 725 local->hw_scan_req->req.scan_6ghz_params = 726 req->scan_6ghz_params; 727 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 728 729 /* 730 * After allocating local->hw_scan_req, we must 731 * go through until ieee80211_prep_hw_scan(), so 732 * anything that might be changed here and leave 733 * this function early must not go after this 734 * allocation. 735 */ 736 } 737 738 rcu_assign_pointer(local->scan_req, req); 739 rcu_assign_pointer(local->scan_sdata, sdata); 740 741 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 742 get_random_mask_addr(local->scan_addr, 743 req->mac_addr, 744 req->mac_addr_mask); 745 else 746 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 747 748 if (hw_scan) { 749 __set_bit(SCAN_HW_SCANNING, &local->scanning); 750 } else if ((req->n_channels == 1) && 751 (req->channels[0] == local->_oper_chandef.chan)) { 752 /* 753 * If we are scanning only on the operating channel 754 * then we do not need to stop normal activities 755 */ 756 unsigned long next_delay; 757 758 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 759 760 ieee80211_recalc_idle(local); 761 762 /* Notify driver scan is starting, keep order of operations 763 * same as normal software scan, in case that matters. */ 764 drv_sw_scan_start(local, sdata, local->scan_addr); 765 766 ieee80211_configure_filter(local); /* accept probe-responses */ 767 768 /* We need to ensure power level is at max for scanning. */ 769 ieee80211_hw_config(local, 0); 770 771 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 772 IEEE80211_CHAN_RADAR)) || 773 !req->n_ssids) { 774 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 775 } else { 776 ieee80211_scan_state_send_probe(local, &next_delay); 777 next_delay = IEEE80211_CHANNEL_TIME; 778 } 779 780 /* Now, just wait a bit and we are all done! */ 781 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 782 next_delay); 783 return 0; 784 } else { 785 /* Do normal software scan */ 786 __set_bit(SCAN_SW_SCANNING, &local->scanning); 787 } 788 789 ieee80211_recalc_idle(local); 790 791 if (hw_scan) { 792 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 793 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 794 } else { 795 rc = ieee80211_start_sw_scan(local, sdata); 796 } 797 798 if (rc) { 799 kfree(local->hw_scan_req); 800 local->hw_scan_req = NULL; 801 local->scanning = 0; 802 803 ieee80211_recalc_idle(local); 804 805 local->scan_req = NULL; 806 RCU_INIT_POINTER(local->scan_sdata, NULL); 807 } 808 809 if (hw_scan && rc == 1) { 810 /* 811 * we can't fall back to software for P2P-GO 812 * as it must update NoA etc. 813 */ 814 if (ieee80211_vif_type_p2p(&sdata->vif) == 815 NL80211_IFTYPE_P2P_GO) 816 return -EOPNOTSUPP; 817 hw_scan = false; 818 goto again; 819 } 820 821 return rc; 822 } 823 824 static unsigned long 825 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 826 { 827 /* 828 * TODO: channel switching also consumes quite some time, 829 * add that delay as well to get a better estimation 830 */ 831 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 832 return IEEE80211_PASSIVE_CHANNEL_TIME; 833 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 834 } 835 836 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 837 unsigned long *next_delay) 838 { 839 bool associated = false; 840 bool tx_empty = true; 841 bool bad_latency; 842 struct ieee80211_sub_if_data *sdata; 843 struct ieee80211_channel *next_chan; 844 enum mac80211_scan_state next_scan_state; 845 struct cfg80211_scan_request *scan_req; 846 847 /* 848 * check if at least one STA interface is associated, 849 * check if at least one STA interface has pending tx frames 850 * and grab the lowest used beacon interval 851 */ 852 mutex_lock(&local->iflist_mtx); 853 list_for_each_entry(sdata, &local->interfaces, list) { 854 if (!ieee80211_sdata_running(sdata)) 855 continue; 856 857 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 858 if (sdata->u.mgd.associated) { 859 associated = true; 860 861 if (!qdisc_all_tx_empty(sdata->dev)) { 862 tx_empty = false; 863 break; 864 } 865 } 866 } 867 } 868 mutex_unlock(&local->iflist_mtx); 869 870 scan_req = rcu_dereference_protected(local->scan_req, 871 lockdep_is_held(&local->mtx)); 872 873 next_chan = scan_req->channels[local->scan_channel_idx]; 874 875 /* 876 * we're currently scanning a different channel, let's 877 * see if we can scan another channel without interfering 878 * with the current traffic situation. 879 * 880 * Keep good latency, do not stay off-channel more than 125 ms. 881 */ 882 883 bad_latency = time_after(jiffies + 884 ieee80211_scan_get_channel_time(next_chan), 885 local->leave_oper_channel_time + HZ / 8); 886 887 if (associated && !tx_empty) { 888 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 889 next_scan_state = SCAN_ABORT; 890 else 891 next_scan_state = SCAN_SUSPEND; 892 } else if (associated && bad_latency) { 893 next_scan_state = SCAN_SUSPEND; 894 } else { 895 next_scan_state = SCAN_SET_CHANNEL; 896 } 897 898 local->next_scan_state = next_scan_state; 899 900 *next_delay = 0; 901 } 902 903 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 904 unsigned long *next_delay) 905 { 906 int skip; 907 struct ieee80211_channel *chan; 908 enum nl80211_bss_scan_width oper_scan_width; 909 struct cfg80211_scan_request *scan_req; 910 911 scan_req = rcu_dereference_protected(local->scan_req, 912 lockdep_is_held(&local->mtx)); 913 914 skip = 0; 915 chan = scan_req->channels[local->scan_channel_idx]; 916 917 local->scan_chandef.chan = chan; 918 local->scan_chandef.center_freq1 = chan->center_freq; 919 local->scan_chandef.freq1_offset = chan->freq_offset; 920 local->scan_chandef.center_freq2 = 0; 921 922 /* For scanning on the S1G band, ignore scan_width (which is constant 923 * across all channels) for now since channel width is specific to each 924 * channel. Detect the required channel width here and likely revisit 925 * later. Maybe scan_width could be used to build the channel scan list? 926 */ 927 if (chan->band == NL80211_BAND_S1GHZ) { 928 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 929 goto set_channel; 930 } 931 932 switch (scan_req->scan_width) { 933 case NL80211_BSS_CHAN_WIDTH_5: 934 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 935 break; 936 case NL80211_BSS_CHAN_WIDTH_10: 937 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 938 break; 939 default: 940 case NL80211_BSS_CHAN_WIDTH_20: 941 /* If scanning on oper channel, use whatever channel-type 942 * is currently in use. 943 */ 944 oper_scan_width = cfg80211_chandef_to_scan_width( 945 &local->_oper_chandef); 946 if (chan == local->_oper_chandef.chan && 947 oper_scan_width == scan_req->scan_width) 948 local->scan_chandef = local->_oper_chandef; 949 else 950 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 951 break; 952 case NL80211_BSS_CHAN_WIDTH_1: 953 case NL80211_BSS_CHAN_WIDTH_2: 954 /* shouldn't get here, S1G handled above */ 955 WARN_ON(1); 956 break; 957 } 958 959 set_channel: 960 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 961 skip = 1; 962 963 /* advance state machine to next channel/band */ 964 local->scan_channel_idx++; 965 966 if (skip) { 967 /* if we skip this channel return to the decision state */ 968 local->next_scan_state = SCAN_DECISION; 969 return; 970 } 971 972 /* 973 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 974 * (which unfortunately doesn't say _why_ step a) is done, 975 * but it waits for the probe delay or until a frame is 976 * received - and the received frame would update the NAV). 977 * For now, we do not support waiting until a frame is 978 * received. 979 * 980 * In any case, it is not necessary for a passive scan. 981 */ 982 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 983 !scan_req->n_ssids) { 984 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 985 local->next_scan_state = SCAN_DECISION; 986 return; 987 } 988 989 /* active scan, send probes */ 990 *next_delay = IEEE80211_PROBE_DELAY; 991 local->next_scan_state = SCAN_SEND_PROBE; 992 } 993 994 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 995 unsigned long *next_delay) 996 { 997 /* switch back to the operating channel */ 998 local->scan_chandef.chan = NULL; 999 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1000 1001 /* disable PS */ 1002 ieee80211_offchannel_return(local); 1003 1004 *next_delay = HZ / 5; 1005 /* afterwards, resume scan & go to next channel */ 1006 local->next_scan_state = SCAN_RESUME; 1007 } 1008 1009 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1010 unsigned long *next_delay) 1011 { 1012 ieee80211_offchannel_stop_vifs(local); 1013 1014 if (local->ops->flush) { 1015 ieee80211_flush_queues(local, NULL, false); 1016 *next_delay = 0; 1017 } else 1018 *next_delay = HZ / 10; 1019 1020 /* remember when we left the operating channel */ 1021 local->leave_oper_channel_time = jiffies; 1022 1023 /* advance to the next channel to be scanned */ 1024 local->next_scan_state = SCAN_SET_CHANNEL; 1025 } 1026 1027 void ieee80211_scan_work(struct work_struct *work) 1028 { 1029 struct ieee80211_local *local = 1030 container_of(work, struct ieee80211_local, scan_work.work); 1031 struct ieee80211_sub_if_data *sdata; 1032 struct cfg80211_scan_request *scan_req; 1033 unsigned long next_delay = 0; 1034 bool aborted; 1035 1036 mutex_lock(&local->mtx); 1037 1038 if (!ieee80211_can_run_worker(local)) { 1039 aborted = true; 1040 goto out_complete; 1041 } 1042 1043 sdata = rcu_dereference_protected(local->scan_sdata, 1044 lockdep_is_held(&local->mtx)); 1045 scan_req = rcu_dereference_protected(local->scan_req, 1046 lockdep_is_held(&local->mtx)); 1047 1048 /* When scanning on-channel, the first-callback means completed. */ 1049 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1050 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1051 goto out_complete; 1052 } 1053 1054 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1055 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1056 goto out_complete; 1057 } 1058 1059 if (!sdata || !scan_req) 1060 goto out; 1061 1062 if (!local->scanning) { 1063 int rc; 1064 1065 RCU_INIT_POINTER(local->scan_req, NULL); 1066 RCU_INIT_POINTER(local->scan_sdata, NULL); 1067 1068 rc = __ieee80211_start_scan(sdata, scan_req); 1069 if (rc) { 1070 /* need to complete scan in cfg80211 */ 1071 rcu_assign_pointer(local->scan_req, scan_req); 1072 aborted = true; 1073 goto out_complete; 1074 } else 1075 goto out; 1076 } 1077 1078 /* 1079 * as long as no delay is required advance immediately 1080 * without scheduling a new work 1081 */ 1082 do { 1083 if (!ieee80211_sdata_running(sdata)) { 1084 aborted = true; 1085 goto out_complete; 1086 } 1087 1088 switch (local->next_scan_state) { 1089 case SCAN_DECISION: 1090 /* if no more bands/channels left, complete scan */ 1091 if (local->scan_channel_idx >= scan_req->n_channels) { 1092 aborted = false; 1093 goto out_complete; 1094 } 1095 ieee80211_scan_state_decision(local, &next_delay); 1096 break; 1097 case SCAN_SET_CHANNEL: 1098 ieee80211_scan_state_set_channel(local, &next_delay); 1099 break; 1100 case SCAN_SEND_PROBE: 1101 ieee80211_scan_state_send_probe(local, &next_delay); 1102 break; 1103 case SCAN_SUSPEND: 1104 ieee80211_scan_state_suspend(local, &next_delay); 1105 break; 1106 case SCAN_RESUME: 1107 ieee80211_scan_state_resume(local, &next_delay); 1108 break; 1109 case SCAN_ABORT: 1110 aborted = true; 1111 goto out_complete; 1112 } 1113 } while (next_delay == 0); 1114 1115 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); 1116 goto out; 1117 1118 out_complete: 1119 __ieee80211_scan_completed(&local->hw, aborted); 1120 out: 1121 mutex_unlock(&local->mtx); 1122 } 1123 1124 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1125 struct cfg80211_scan_request *req) 1126 { 1127 int res; 1128 1129 mutex_lock(&sdata->local->mtx); 1130 res = __ieee80211_start_scan(sdata, req); 1131 mutex_unlock(&sdata->local->mtx); 1132 1133 return res; 1134 } 1135 1136 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1137 const u8 *ssid, u8 ssid_len, 1138 struct ieee80211_channel **channels, 1139 unsigned int n_channels, 1140 enum nl80211_bss_scan_width scan_width) 1141 { 1142 struct ieee80211_local *local = sdata->local; 1143 int ret = -EBUSY, i, n_ch = 0; 1144 enum nl80211_band band; 1145 1146 mutex_lock(&local->mtx); 1147 1148 /* busy scanning */ 1149 if (local->scan_req) 1150 goto unlock; 1151 1152 /* fill internal scan request */ 1153 if (!channels) { 1154 int max_n; 1155 1156 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1157 if (!local->hw.wiphy->bands[band] || 1158 band == NL80211_BAND_6GHZ) 1159 continue; 1160 1161 max_n = local->hw.wiphy->bands[band]->n_channels; 1162 for (i = 0; i < max_n; i++) { 1163 struct ieee80211_channel *tmp_ch = 1164 &local->hw.wiphy->bands[band]->channels[i]; 1165 1166 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1167 IEEE80211_CHAN_DISABLED)) 1168 continue; 1169 1170 local->int_scan_req->channels[n_ch] = tmp_ch; 1171 n_ch++; 1172 } 1173 } 1174 1175 if (WARN_ON_ONCE(n_ch == 0)) 1176 goto unlock; 1177 1178 local->int_scan_req->n_channels = n_ch; 1179 } else { 1180 for (i = 0; i < n_channels; i++) { 1181 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1182 IEEE80211_CHAN_DISABLED)) 1183 continue; 1184 1185 local->int_scan_req->channels[n_ch] = channels[i]; 1186 n_ch++; 1187 } 1188 1189 if (WARN_ON_ONCE(n_ch == 0)) 1190 goto unlock; 1191 1192 local->int_scan_req->n_channels = n_ch; 1193 } 1194 1195 local->int_scan_req->ssids = &local->scan_ssid; 1196 local->int_scan_req->n_ssids = 1; 1197 local->int_scan_req->scan_width = scan_width; 1198 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1199 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1200 1201 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1202 unlock: 1203 mutex_unlock(&local->mtx); 1204 return ret; 1205 } 1206 1207 /* 1208 * Only call this function when a scan can't be queued -- under RTNL. 1209 */ 1210 void ieee80211_scan_cancel(struct ieee80211_local *local) 1211 { 1212 /* 1213 * We are canceling software scan, or deferred scan that was not 1214 * yet really started (see __ieee80211_start_scan ). 1215 * 1216 * Regarding hardware scan: 1217 * - we can not call __ieee80211_scan_completed() as when 1218 * SCAN_HW_SCANNING bit is set this function change 1219 * local->hw_scan_req to operate on 5G band, what race with 1220 * driver which can use local->hw_scan_req 1221 * 1222 * - we can not cancel scan_work since driver can schedule it 1223 * by ieee80211_scan_completed(..., true) to finish scan 1224 * 1225 * Hence we only call the cancel_hw_scan() callback, but the low-level 1226 * driver is still responsible for calling ieee80211_scan_completed() 1227 * after the scan was completed/aborted. 1228 */ 1229 1230 mutex_lock(&local->mtx); 1231 if (!local->scan_req) 1232 goto out; 1233 1234 /* 1235 * We have a scan running and the driver already reported completion, 1236 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1237 * cancelled. 1238 */ 1239 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1240 test_bit(SCAN_COMPLETED, &local->scanning)) { 1241 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1242 goto out; 1243 } 1244 1245 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1246 /* 1247 * Make sure that __ieee80211_scan_completed doesn't trigger a 1248 * scan on another band. 1249 */ 1250 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1251 if (local->ops->cancel_hw_scan) 1252 drv_cancel_hw_scan(local, 1253 rcu_dereference_protected(local->scan_sdata, 1254 lockdep_is_held(&local->mtx))); 1255 goto out; 1256 } 1257 1258 /* 1259 * If the work is currently running, it must be blocked on 1260 * the mutex, but we'll set scan_sdata = NULL and it'll 1261 * simply exit once it acquires the mutex. 1262 */ 1263 cancel_delayed_work(&local->scan_work); 1264 /* and clean up */ 1265 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1266 __ieee80211_scan_completed(&local->hw, true); 1267 out: 1268 mutex_unlock(&local->mtx); 1269 } 1270 1271 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1272 struct cfg80211_sched_scan_request *req) 1273 { 1274 struct ieee80211_local *local = sdata->local; 1275 struct ieee80211_scan_ies sched_scan_ies = {}; 1276 struct cfg80211_chan_def chandef; 1277 int ret, i, iebufsz, num_bands = 0; 1278 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1279 u8 bands_used = 0; 1280 u8 *ie; 1281 u32 flags = 0; 1282 1283 iebufsz = local->scan_ies_len + req->ie_len; 1284 1285 lockdep_assert_held(&local->mtx); 1286 1287 if (!local->ops->sched_scan_start) 1288 return -ENOTSUPP; 1289 1290 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1291 if (local->hw.wiphy->bands[i]) { 1292 bands_used |= BIT(i); 1293 rate_masks[i] = (u32) -1; 1294 num_bands++; 1295 } 1296 } 1297 1298 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1299 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1300 1301 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1302 if (!ie) { 1303 ret = -ENOMEM; 1304 goto out; 1305 } 1306 1307 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1308 1309 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1310 &sched_scan_ies, req->ie, 1311 req->ie_len, bands_used, rate_masks, &chandef, 1312 flags); 1313 1314 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1315 if (ret == 0) { 1316 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1317 rcu_assign_pointer(local->sched_scan_req, req); 1318 } 1319 1320 kfree(ie); 1321 1322 out: 1323 if (ret) { 1324 /* Clean in case of failure after HW restart or upon resume. */ 1325 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1326 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1327 } 1328 1329 return ret; 1330 } 1331 1332 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1333 struct cfg80211_sched_scan_request *req) 1334 { 1335 struct ieee80211_local *local = sdata->local; 1336 int ret; 1337 1338 mutex_lock(&local->mtx); 1339 1340 if (rcu_access_pointer(local->sched_scan_sdata)) { 1341 mutex_unlock(&local->mtx); 1342 return -EBUSY; 1343 } 1344 1345 ret = __ieee80211_request_sched_scan_start(sdata, req); 1346 1347 mutex_unlock(&local->mtx); 1348 return ret; 1349 } 1350 1351 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1352 { 1353 struct ieee80211_sub_if_data *sched_scan_sdata; 1354 int ret = -ENOENT; 1355 1356 mutex_lock(&local->mtx); 1357 1358 if (!local->ops->sched_scan_stop) { 1359 ret = -ENOTSUPP; 1360 goto out; 1361 } 1362 1363 /* We don't want to restart sched scan anymore. */ 1364 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1365 1366 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1367 lockdep_is_held(&local->mtx)); 1368 if (sched_scan_sdata) { 1369 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1370 if (!ret) 1371 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1372 } 1373 out: 1374 mutex_unlock(&local->mtx); 1375 1376 return ret; 1377 } 1378 1379 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1380 { 1381 struct ieee80211_local *local = hw_to_local(hw); 1382 1383 trace_api_sched_scan_results(local); 1384 1385 cfg80211_sched_scan_results(hw->wiphy, 0); 1386 } 1387 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1388 1389 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1390 { 1391 mutex_lock(&local->mtx); 1392 1393 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1394 mutex_unlock(&local->mtx); 1395 return; 1396 } 1397 1398 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1399 1400 /* If sched scan was aborted by the driver. */ 1401 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1402 1403 mutex_unlock(&local->mtx); 1404 1405 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1406 } 1407 1408 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1409 { 1410 struct ieee80211_local *local = 1411 container_of(work, struct ieee80211_local, 1412 sched_scan_stopped_work); 1413 1414 ieee80211_sched_scan_end(local); 1415 } 1416 1417 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1418 { 1419 struct ieee80211_local *local = hw_to_local(hw); 1420 1421 trace_api_sched_scan_stopped(local); 1422 1423 /* 1424 * this shouldn't really happen, so for simplicity 1425 * simply ignore it, and let mac80211 reconfigure 1426 * the sched scan later on. 1427 */ 1428 if (local->in_reconfig) 1429 return; 1430 1431 schedule_work(&local->sched_scan_stopped_work); 1432 } 1433 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1434