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) 2018-2021 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 elems = ieee802_11_parse_elems(elements, len - baselen, false, 213 mgmt->bssid, cbss->bssid); 214 if (!elems) 215 return NULL; 216 217 /* In case the signal is invalid update the status */ 218 signal_valid = channel == cbss->channel; 219 if (!signal_valid) 220 rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL; 221 222 bss = (void *)cbss->priv; 223 ieee80211_update_bss_from_elems(local, bss, elems, rx_status, beacon); 224 225 list_for_each_entry(non_tx_cbss, &cbss->nontrans_list, nontrans_list) { 226 non_tx_bss = (void *)non_tx_cbss->priv; 227 228 ieee80211_update_bss_from_elems(local, non_tx_bss, elems, 229 rx_status, beacon); 230 } 231 232 kfree(elems); 233 234 return bss; 235 } 236 237 static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata, 238 u32 scan_flags, const u8 *da) 239 { 240 if (!sdata) 241 return false; 242 /* accept broadcast for OCE */ 243 if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP && 244 is_broadcast_ether_addr(da)) 245 return true; 246 if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 247 return true; 248 return ether_addr_equal(da, sdata->vif.addr); 249 } 250 251 void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) 252 { 253 struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); 254 struct ieee80211_sub_if_data *sdata1, *sdata2; 255 struct ieee80211_mgmt *mgmt = (void *)skb->data; 256 struct ieee80211_bss *bss; 257 struct ieee80211_channel *channel; 258 size_t min_hdr_len = offsetof(struct ieee80211_mgmt, 259 u.probe_resp.variable); 260 261 if (!ieee80211_is_probe_resp(mgmt->frame_control) && 262 !ieee80211_is_beacon(mgmt->frame_control) && 263 !ieee80211_is_s1g_beacon(mgmt->frame_control)) 264 return; 265 266 if (ieee80211_is_s1g_beacon(mgmt->frame_control)) { 267 if (ieee80211_is_s1g_short_beacon(mgmt->frame_control)) 268 min_hdr_len = offsetof(struct ieee80211_ext, 269 u.s1g_short_beacon.variable); 270 else 271 min_hdr_len = offsetof(struct ieee80211_ext, 272 u.s1g_beacon); 273 } 274 275 if (skb->len < min_hdr_len) 276 return; 277 278 sdata1 = rcu_dereference(local->scan_sdata); 279 sdata2 = rcu_dereference(local->sched_scan_sdata); 280 281 if (likely(!sdata1 && !sdata2)) 282 return; 283 284 if (ieee80211_is_probe_resp(mgmt->frame_control)) { 285 struct cfg80211_scan_request *scan_req; 286 struct cfg80211_sched_scan_request *sched_scan_req; 287 u32 scan_req_flags = 0, sched_scan_req_flags = 0; 288 289 scan_req = rcu_dereference(local->scan_req); 290 sched_scan_req = rcu_dereference(local->sched_scan_req); 291 292 if (scan_req) 293 scan_req_flags = scan_req->flags; 294 295 if (sched_scan_req) 296 sched_scan_req_flags = sched_scan_req->flags; 297 298 /* ignore ProbeResp to foreign address or non-bcast (OCE) 299 * unless scanning with randomised address 300 */ 301 if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags, 302 mgmt->da) && 303 !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags, 304 mgmt->da)) 305 return; 306 } 307 308 channel = ieee80211_get_channel_khz(local->hw.wiphy, 309 ieee80211_rx_status_to_khz(rx_status)); 310 311 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 312 return; 313 314 bss = ieee80211_bss_info_update(local, rx_status, 315 mgmt, skb->len, 316 channel); 317 if (bss) 318 ieee80211_rx_bss_put(local, bss); 319 } 320 321 static void 322 ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef, 323 enum nl80211_bss_scan_width scan_width) 324 { 325 memset(chandef, 0, sizeof(*chandef)); 326 switch (scan_width) { 327 case NL80211_BSS_CHAN_WIDTH_5: 328 chandef->width = NL80211_CHAN_WIDTH_5; 329 break; 330 case NL80211_BSS_CHAN_WIDTH_10: 331 chandef->width = NL80211_CHAN_WIDTH_10; 332 break; 333 default: 334 chandef->width = NL80211_CHAN_WIDTH_20_NOHT; 335 break; 336 } 337 } 338 339 /* return false if no more work */ 340 static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata) 341 { 342 struct ieee80211_local *local = sdata->local; 343 struct cfg80211_scan_request *req; 344 struct cfg80211_chan_def chandef; 345 u8 bands_used = 0; 346 int i, ielen, n_chans; 347 u32 flags = 0; 348 349 req = rcu_dereference_protected(local->scan_req, 350 lockdep_is_held(&local->mtx)); 351 352 if (test_bit(SCAN_HW_CANCELLED, &local->scanning)) 353 return false; 354 355 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 356 for (i = 0; i < req->n_channels; i++) { 357 local->hw_scan_req->req.channels[i] = req->channels[i]; 358 bands_used |= BIT(req->channels[i]->band); 359 } 360 361 n_chans = req->n_channels; 362 } else { 363 do { 364 if (local->hw_scan_band == NUM_NL80211_BANDS) 365 return false; 366 367 n_chans = 0; 368 369 for (i = 0; i < req->n_channels; i++) { 370 if (req->channels[i]->band != 371 local->hw_scan_band) 372 continue; 373 local->hw_scan_req->req.channels[n_chans] = 374 req->channels[i]; 375 n_chans++; 376 bands_used |= BIT(req->channels[i]->band); 377 } 378 379 local->hw_scan_band++; 380 } while (!n_chans); 381 } 382 383 local->hw_scan_req->req.n_channels = n_chans; 384 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 385 386 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 387 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 388 389 ielen = ieee80211_build_preq_ies(sdata, 390 (u8 *)local->hw_scan_req->req.ie, 391 local->hw_scan_ies_bufsize, 392 &local->hw_scan_req->ies, 393 req->ie, req->ie_len, 394 bands_used, req->rates, &chandef, 395 flags); 396 local->hw_scan_req->req.ie_len = ielen; 397 local->hw_scan_req->req.no_cck = req->no_cck; 398 ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr); 399 ether_addr_copy(local->hw_scan_req->req.mac_addr_mask, 400 req->mac_addr_mask); 401 ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid); 402 403 return true; 404 } 405 406 static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) 407 { 408 struct ieee80211_local *local = hw_to_local(hw); 409 bool hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); 410 bool was_scanning = local->scanning; 411 struct cfg80211_scan_request *scan_req; 412 struct ieee80211_sub_if_data *scan_sdata; 413 struct ieee80211_sub_if_data *sdata; 414 415 lockdep_assert_held(&local->mtx); 416 417 /* 418 * It's ok to abort a not-yet-running scan (that 419 * we have one at all will be verified by checking 420 * local->scan_req next), but not to complete it 421 * successfully. 422 */ 423 if (WARN_ON(!local->scanning && !aborted)) 424 aborted = true; 425 426 if (WARN_ON(!local->scan_req)) 427 return; 428 429 scan_sdata = rcu_dereference_protected(local->scan_sdata, 430 lockdep_is_held(&local->mtx)); 431 432 if (hw_scan && !aborted && 433 !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) && 434 ieee80211_prep_hw_scan(scan_sdata)) { 435 int rc; 436 437 rc = drv_hw_scan(local, 438 rcu_dereference_protected(local->scan_sdata, 439 lockdep_is_held(&local->mtx)), 440 local->hw_scan_req); 441 442 if (rc == 0) 443 return; 444 445 /* HW scan failed and is going to be reported as aborted, 446 * so clear old scan info. 447 */ 448 memset(&local->scan_info, 0, sizeof(local->scan_info)); 449 aborted = true; 450 } 451 452 kfree(local->hw_scan_req); 453 local->hw_scan_req = NULL; 454 455 scan_req = rcu_dereference_protected(local->scan_req, 456 lockdep_is_held(&local->mtx)); 457 458 if (scan_req != local->int_scan_req) { 459 local->scan_info.aborted = aborted; 460 cfg80211_scan_done(scan_req, &local->scan_info); 461 } 462 RCU_INIT_POINTER(local->scan_req, NULL); 463 RCU_INIT_POINTER(local->scan_sdata, NULL); 464 465 local->scanning = 0; 466 local->scan_chandef.chan = NULL; 467 468 /* Set power back to normal operating levels. */ 469 ieee80211_hw_config(local, 0); 470 471 if (!hw_scan) { 472 ieee80211_configure_filter(local); 473 drv_sw_scan_complete(local, scan_sdata); 474 ieee80211_offchannel_return(local); 475 } 476 477 ieee80211_recalc_idle(local); 478 479 ieee80211_mlme_notify_scan_completed(local); 480 ieee80211_ibss_notify_scan_completed(local); 481 482 /* Requeue all the work that might have been ignored while 483 * the scan was in progress; if there was none this will 484 * just be a no-op for the particular interface. 485 */ 486 list_for_each_entry_rcu(sdata, &local->interfaces, list) { 487 if (ieee80211_sdata_running(sdata)) 488 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 489 } 490 491 if (was_scanning) 492 ieee80211_start_next_roc(local); 493 } 494 495 void ieee80211_scan_completed(struct ieee80211_hw *hw, 496 struct cfg80211_scan_info *info) 497 { 498 struct ieee80211_local *local = hw_to_local(hw); 499 500 trace_api_scan_completed(local, info->aborted); 501 502 set_bit(SCAN_COMPLETED, &local->scanning); 503 if (info->aborted) 504 set_bit(SCAN_ABORTED, &local->scanning); 505 506 memcpy(&local->scan_info, info, sizeof(*info)); 507 508 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); 509 } 510 EXPORT_SYMBOL(ieee80211_scan_completed); 511 512 static int ieee80211_start_sw_scan(struct ieee80211_local *local, 513 struct ieee80211_sub_if_data *sdata) 514 { 515 /* Software scan is not supported in multi-channel cases */ 516 if (local->use_chanctx) 517 return -EOPNOTSUPP; 518 519 /* 520 * Hardware/driver doesn't support hw_scan, so use software 521 * scanning instead. First send a nullfunc frame with power save 522 * bit on so that AP will buffer the frames for us while we are not 523 * listening, then send probe requests to each channel and wait for 524 * the responses. After all channels are scanned, tune back to the 525 * original channel and send a nullfunc frame with power save bit 526 * off to trigger the AP to send us all the buffered frames. 527 * 528 * Note that while local->sw_scanning is true everything else but 529 * nullfunc frames and probe requests will be dropped in 530 * ieee80211_tx_h_check_assoc(). 531 */ 532 drv_sw_scan_start(local, sdata, local->scan_addr); 533 534 local->leave_oper_channel_time = jiffies; 535 local->next_scan_state = SCAN_DECISION; 536 local->scan_channel_idx = 0; 537 538 ieee80211_offchannel_stop_vifs(local); 539 540 /* ensure nullfunc is transmitted before leaving operating channel */ 541 ieee80211_flush_queues(local, NULL, false); 542 543 ieee80211_configure_filter(local); 544 545 /* We need to set power level at maximum rate for scanning. */ 546 ieee80211_hw_config(local, 0); 547 548 ieee80211_queue_delayed_work(&local->hw, 549 &local->scan_work, 0); 550 551 return 0; 552 } 553 554 static bool __ieee80211_can_leave_ch(struct ieee80211_sub_if_data *sdata) 555 { 556 struct ieee80211_local *local = sdata->local; 557 struct ieee80211_sub_if_data *sdata_iter; 558 559 if (!ieee80211_is_radar_required(local)) 560 return true; 561 562 if (!regulatory_pre_cac_allowed(local->hw.wiphy)) 563 return false; 564 565 mutex_lock(&local->iflist_mtx); 566 list_for_each_entry(sdata_iter, &local->interfaces, list) { 567 if (sdata_iter->wdev.cac_started) { 568 mutex_unlock(&local->iflist_mtx); 569 return false; 570 } 571 } 572 mutex_unlock(&local->iflist_mtx); 573 574 return true; 575 } 576 577 static bool ieee80211_can_scan(struct ieee80211_local *local, 578 struct ieee80211_sub_if_data *sdata) 579 { 580 if (!__ieee80211_can_leave_ch(sdata)) 581 return false; 582 583 if (!list_empty(&local->roc_list)) 584 return false; 585 586 if (sdata->vif.type == NL80211_IFTYPE_STATION && 587 sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL) 588 return false; 589 590 return true; 591 } 592 593 void ieee80211_run_deferred_scan(struct ieee80211_local *local) 594 { 595 lockdep_assert_held(&local->mtx); 596 597 if (!local->scan_req || local->scanning) 598 return; 599 600 if (!ieee80211_can_scan(local, 601 rcu_dereference_protected( 602 local->scan_sdata, 603 lockdep_is_held(&local->mtx)))) 604 return; 605 606 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 607 round_jiffies_relative(0)); 608 } 609 610 static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, 611 const u8 *src, const u8 *dst, 612 const u8 *ssid, size_t ssid_len, 613 const u8 *ie, size_t ie_len, 614 u32 ratemask, u32 flags, u32 tx_flags, 615 struct ieee80211_channel *channel) 616 { 617 struct sk_buff *skb; 618 619 skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel, 620 ssid, ssid_len, 621 ie, ie_len, flags); 622 623 if (skb) { 624 if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { 625 struct ieee80211_hdr *hdr = (void *)skb->data; 626 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 627 u16 sn = get_random_u32(); 628 629 info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; 630 hdr->seq_ctrl = 631 cpu_to_le16(IEEE80211_SN_TO_SEQ(sn)); 632 } 633 IEEE80211_SKB_CB(skb)->flags |= tx_flags; 634 ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band); 635 } 636 } 637 638 static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, 639 unsigned long *next_delay) 640 { 641 int i; 642 struct ieee80211_sub_if_data *sdata; 643 struct cfg80211_scan_request *scan_req; 644 enum nl80211_band band = local->hw.conf.chandef.chan->band; 645 u32 flags = 0, tx_flags; 646 647 scan_req = rcu_dereference_protected(local->scan_req, 648 lockdep_is_held(&local->mtx)); 649 650 tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK; 651 if (scan_req->no_cck) 652 tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE; 653 if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 654 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 655 if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN) 656 flags |= IEEE80211_PROBE_FLAG_RANDOM_SN; 657 658 sdata = rcu_dereference_protected(local->scan_sdata, 659 lockdep_is_held(&local->mtx)); 660 661 for (i = 0; i < scan_req->n_ssids; i++) 662 ieee80211_send_scan_probe_req( 663 sdata, local->scan_addr, scan_req->bssid, 664 scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len, 665 scan_req->ie, scan_req->ie_len, 666 scan_req->rates[band], flags, 667 tx_flags, local->hw.conf.chandef.chan); 668 669 /* 670 * After sending probe requests, wait for probe responses 671 * on the channel. 672 */ 673 *next_delay = IEEE80211_CHANNEL_TIME; 674 local->next_scan_state = SCAN_DECISION; 675 } 676 677 static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, 678 struct cfg80211_scan_request *req) 679 { 680 struct ieee80211_local *local = sdata->local; 681 bool hw_scan = local->ops->hw_scan; 682 int rc; 683 684 lockdep_assert_held(&local->mtx); 685 686 if (local->scan_req) 687 return -EBUSY; 688 689 if (!__ieee80211_can_leave_ch(sdata)) 690 return -EBUSY; 691 692 if (!ieee80211_can_scan(local, sdata)) { 693 /* wait for the work to finish/time out */ 694 rcu_assign_pointer(local->scan_req, req); 695 rcu_assign_pointer(local->scan_sdata, sdata); 696 return 0; 697 } 698 699 again: 700 if (hw_scan) { 701 u8 *ies; 702 703 local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len; 704 705 if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) { 706 int i, n_bands = 0; 707 u8 bands_counted = 0; 708 709 for (i = 0; i < req->n_channels; i++) { 710 if (bands_counted & BIT(req->channels[i]->band)) 711 continue; 712 bands_counted |= BIT(req->channels[i]->band); 713 n_bands++; 714 } 715 716 local->hw_scan_ies_bufsize *= n_bands; 717 } 718 719 local->hw_scan_req = kmalloc( 720 sizeof(*local->hw_scan_req) + 721 req->n_channels * sizeof(req->channels[0]) + 722 local->hw_scan_ies_bufsize, GFP_KERNEL); 723 if (!local->hw_scan_req) 724 return -ENOMEM; 725 726 local->hw_scan_req->req.ssids = req->ssids; 727 local->hw_scan_req->req.n_ssids = req->n_ssids; 728 ies = (u8 *)local->hw_scan_req + 729 sizeof(*local->hw_scan_req) + 730 req->n_channels * sizeof(req->channels[0]); 731 local->hw_scan_req->req.ie = ies; 732 local->hw_scan_req->req.flags = req->flags; 733 eth_broadcast_addr(local->hw_scan_req->req.bssid); 734 local->hw_scan_req->req.duration = req->duration; 735 local->hw_scan_req->req.duration_mandatory = 736 req->duration_mandatory; 737 738 local->hw_scan_band = 0; 739 local->hw_scan_req->req.n_6ghz_params = req->n_6ghz_params; 740 local->hw_scan_req->req.scan_6ghz_params = 741 req->scan_6ghz_params; 742 local->hw_scan_req->req.scan_6ghz = req->scan_6ghz; 743 744 /* 745 * After allocating local->hw_scan_req, we must 746 * go through until ieee80211_prep_hw_scan(), so 747 * anything that might be changed here and leave 748 * this function early must not go after this 749 * allocation. 750 */ 751 } 752 753 rcu_assign_pointer(local->scan_req, req); 754 rcu_assign_pointer(local->scan_sdata, sdata); 755 756 if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) 757 get_random_mask_addr(local->scan_addr, 758 req->mac_addr, 759 req->mac_addr_mask); 760 else 761 memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN); 762 763 if (hw_scan) { 764 __set_bit(SCAN_HW_SCANNING, &local->scanning); 765 } else if ((req->n_channels == 1) && 766 (req->channels[0] == local->_oper_chandef.chan)) { 767 /* 768 * If we are scanning only on the operating channel 769 * then we do not need to stop normal activities 770 */ 771 unsigned long next_delay; 772 773 __set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning); 774 775 ieee80211_recalc_idle(local); 776 777 /* Notify driver scan is starting, keep order of operations 778 * same as normal software scan, in case that matters. */ 779 drv_sw_scan_start(local, sdata, local->scan_addr); 780 781 ieee80211_configure_filter(local); /* accept probe-responses */ 782 783 /* We need to ensure power level is at max for scanning. */ 784 ieee80211_hw_config(local, 0); 785 786 if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR | 787 IEEE80211_CHAN_RADAR)) || 788 !req->n_ssids) { 789 next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 790 } else { 791 ieee80211_scan_state_send_probe(local, &next_delay); 792 next_delay = IEEE80211_CHANNEL_TIME; 793 } 794 795 /* Now, just wait a bit and we are all done! */ 796 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 797 next_delay); 798 return 0; 799 } else { 800 /* Do normal software scan */ 801 __set_bit(SCAN_SW_SCANNING, &local->scanning); 802 } 803 804 ieee80211_recalc_idle(local); 805 806 if (hw_scan) { 807 WARN_ON(!ieee80211_prep_hw_scan(sdata)); 808 rc = drv_hw_scan(local, sdata, local->hw_scan_req); 809 } else { 810 rc = ieee80211_start_sw_scan(local, sdata); 811 } 812 813 if (rc) { 814 kfree(local->hw_scan_req); 815 local->hw_scan_req = NULL; 816 local->scanning = 0; 817 818 ieee80211_recalc_idle(local); 819 820 local->scan_req = NULL; 821 RCU_INIT_POINTER(local->scan_sdata, NULL); 822 } 823 824 if (hw_scan && rc == 1) { 825 /* 826 * we can't fall back to software for P2P-GO 827 * as it must update NoA etc. 828 */ 829 if (ieee80211_vif_type_p2p(&sdata->vif) == 830 NL80211_IFTYPE_P2P_GO) 831 return -EOPNOTSUPP; 832 hw_scan = false; 833 goto again; 834 } 835 836 return rc; 837 } 838 839 static unsigned long 840 ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) 841 { 842 /* 843 * TODO: channel switching also consumes quite some time, 844 * add that delay as well to get a better estimation 845 */ 846 if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) 847 return IEEE80211_PASSIVE_CHANNEL_TIME; 848 return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; 849 } 850 851 static void ieee80211_scan_state_decision(struct ieee80211_local *local, 852 unsigned long *next_delay) 853 { 854 bool associated = false; 855 bool tx_empty = true; 856 bool bad_latency; 857 struct ieee80211_sub_if_data *sdata; 858 struct ieee80211_channel *next_chan; 859 enum mac80211_scan_state next_scan_state; 860 struct cfg80211_scan_request *scan_req; 861 862 /* 863 * check if at least one STA interface is associated, 864 * check if at least one STA interface has pending tx frames 865 * and grab the lowest used beacon interval 866 */ 867 mutex_lock(&local->iflist_mtx); 868 list_for_each_entry(sdata, &local->interfaces, list) { 869 if (!ieee80211_sdata_running(sdata)) 870 continue; 871 872 if (sdata->vif.type == NL80211_IFTYPE_STATION) { 873 if (sdata->u.mgd.associated) { 874 associated = true; 875 876 if (!qdisc_all_tx_empty(sdata->dev)) { 877 tx_empty = false; 878 break; 879 } 880 } 881 } 882 } 883 mutex_unlock(&local->iflist_mtx); 884 885 scan_req = rcu_dereference_protected(local->scan_req, 886 lockdep_is_held(&local->mtx)); 887 888 next_chan = scan_req->channels[local->scan_channel_idx]; 889 890 /* 891 * we're currently scanning a different channel, let's 892 * see if we can scan another channel without interfering 893 * with the current traffic situation. 894 * 895 * Keep good latency, do not stay off-channel more than 125 ms. 896 */ 897 898 bad_latency = time_after(jiffies + 899 ieee80211_scan_get_channel_time(next_chan), 900 local->leave_oper_channel_time + HZ / 8); 901 902 if (associated && !tx_empty) { 903 if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY) 904 next_scan_state = SCAN_ABORT; 905 else 906 next_scan_state = SCAN_SUSPEND; 907 } else if (associated && bad_latency) { 908 next_scan_state = SCAN_SUSPEND; 909 } else { 910 next_scan_state = SCAN_SET_CHANNEL; 911 } 912 913 local->next_scan_state = next_scan_state; 914 915 *next_delay = 0; 916 } 917 918 static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, 919 unsigned long *next_delay) 920 { 921 int skip; 922 struct ieee80211_channel *chan; 923 enum nl80211_bss_scan_width oper_scan_width; 924 struct cfg80211_scan_request *scan_req; 925 926 scan_req = rcu_dereference_protected(local->scan_req, 927 lockdep_is_held(&local->mtx)); 928 929 skip = 0; 930 chan = scan_req->channels[local->scan_channel_idx]; 931 932 local->scan_chandef.chan = chan; 933 local->scan_chandef.center_freq1 = chan->center_freq; 934 local->scan_chandef.freq1_offset = chan->freq_offset; 935 local->scan_chandef.center_freq2 = 0; 936 937 /* For scanning on the S1G band, ignore scan_width (which is constant 938 * across all channels) for now since channel width is specific to each 939 * channel. Detect the required channel width here and likely revisit 940 * later. Maybe scan_width could be used to build the channel scan list? 941 */ 942 if (chan->band == NL80211_BAND_S1GHZ) { 943 local->scan_chandef.width = ieee80211_s1g_channel_width(chan); 944 goto set_channel; 945 } 946 947 switch (scan_req->scan_width) { 948 case NL80211_BSS_CHAN_WIDTH_5: 949 local->scan_chandef.width = NL80211_CHAN_WIDTH_5; 950 break; 951 case NL80211_BSS_CHAN_WIDTH_10: 952 local->scan_chandef.width = NL80211_CHAN_WIDTH_10; 953 break; 954 default: 955 case NL80211_BSS_CHAN_WIDTH_20: 956 /* If scanning on oper channel, use whatever channel-type 957 * is currently in use. 958 */ 959 oper_scan_width = cfg80211_chandef_to_scan_width( 960 &local->_oper_chandef); 961 if (chan == local->_oper_chandef.chan && 962 oper_scan_width == scan_req->scan_width) 963 local->scan_chandef = local->_oper_chandef; 964 else 965 local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT; 966 break; 967 case NL80211_BSS_CHAN_WIDTH_1: 968 case NL80211_BSS_CHAN_WIDTH_2: 969 /* shouldn't get here, S1G handled above */ 970 WARN_ON(1); 971 break; 972 } 973 974 set_channel: 975 if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) 976 skip = 1; 977 978 /* advance state machine to next channel/band */ 979 local->scan_channel_idx++; 980 981 if (skip) { 982 /* if we skip this channel return to the decision state */ 983 local->next_scan_state = SCAN_DECISION; 984 return; 985 } 986 987 /* 988 * Probe delay is used to update the NAV, cf. 11.1.3.2.2 989 * (which unfortunately doesn't say _why_ step a) is done, 990 * but it waits for the probe delay or until a frame is 991 * received - and the received frame would update the NAV). 992 * For now, we do not support waiting until a frame is 993 * received. 994 * 995 * In any case, it is not necessary for a passive scan. 996 */ 997 if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) || 998 !scan_req->n_ssids) { 999 *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; 1000 local->next_scan_state = SCAN_DECISION; 1001 return; 1002 } 1003 1004 /* active scan, send probes */ 1005 *next_delay = IEEE80211_PROBE_DELAY; 1006 local->next_scan_state = SCAN_SEND_PROBE; 1007 } 1008 1009 static void ieee80211_scan_state_suspend(struct ieee80211_local *local, 1010 unsigned long *next_delay) 1011 { 1012 /* switch back to the operating channel */ 1013 local->scan_chandef.chan = NULL; 1014 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 1015 1016 /* disable PS */ 1017 ieee80211_offchannel_return(local); 1018 1019 *next_delay = HZ / 5; 1020 /* afterwards, resume scan & go to next channel */ 1021 local->next_scan_state = SCAN_RESUME; 1022 } 1023 1024 static void ieee80211_scan_state_resume(struct ieee80211_local *local, 1025 unsigned long *next_delay) 1026 { 1027 ieee80211_offchannel_stop_vifs(local); 1028 1029 if (local->ops->flush) { 1030 ieee80211_flush_queues(local, NULL, false); 1031 *next_delay = 0; 1032 } else 1033 *next_delay = HZ / 10; 1034 1035 /* remember when we left the operating channel */ 1036 local->leave_oper_channel_time = jiffies; 1037 1038 /* advance to the next channel to be scanned */ 1039 local->next_scan_state = SCAN_SET_CHANNEL; 1040 } 1041 1042 void ieee80211_scan_work(struct work_struct *work) 1043 { 1044 struct ieee80211_local *local = 1045 container_of(work, struct ieee80211_local, scan_work.work); 1046 struct ieee80211_sub_if_data *sdata; 1047 struct cfg80211_scan_request *scan_req; 1048 unsigned long next_delay = 0; 1049 bool aborted; 1050 1051 mutex_lock(&local->mtx); 1052 1053 if (!ieee80211_can_run_worker(local)) { 1054 aborted = true; 1055 goto out_complete; 1056 } 1057 1058 sdata = rcu_dereference_protected(local->scan_sdata, 1059 lockdep_is_held(&local->mtx)); 1060 scan_req = rcu_dereference_protected(local->scan_req, 1061 lockdep_is_held(&local->mtx)); 1062 1063 /* When scanning on-channel, the first-callback means completed. */ 1064 if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) { 1065 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1066 goto out_complete; 1067 } 1068 1069 if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { 1070 aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); 1071 goto out_complete; 1072 } 1073 1074 if (!sdata || !scan_req) 1075 goto out; 1076 1077 if (!local->scanning) { 1078 int rc; 1079 1080 RCU_INIT_POINTER(local->scan_req, NULL); 1081 RCU_INIT_POINTER(local->scan_sdata, NULL); 1082 1083 rc = __ieee80211_start_scan(sdata, scan_req); 1084 if (rc) { 1085 /* need to complete scan in cfg80211 */ 1086 rcu_assign_pointer(local->scan_req, scan_req); 1087 aborted = true; 1088 goto out_complete; 1089 } else 1090 goto out; 1091 } 1092 1093 /* 1094 * as long as no delay is required advance immediately 1095 * without scheduling a new work 1096 */ 1097 do { 1098 if (!ieee80211_sdata_running(sdata)) { 1099 aborted = true; 1100 goto out_complete; 1101 } 1102 1103 switch (local->next_scan_state) { 1104 case SCAN_DECISION: 1105 /* if no more bands/channels left, complete scan */ 1106 if (local->scan_channel_idx >= scan_req->n_channels) { 1107 aborted = false; 1108 goto out_complete; 1109 } 1110 ieee80211_scan_state_decision(local, &next_delay); 1111 break; 1112 case SCAN_SET_CHANNEL: 1113 ieee80211_scan_state_set_channel(local, &next_delay); 1114 break; 1115 case SCAN_SEND_PROBE: 1116 ieee80211_scan_state_send_probe(local, &next_delay); 1117 break; 1118 case SCAN_SUSPEND: 1119 ieee80211_scan_state_suspend(local, &next_delay); 1120 break; 1121 case SCAN_RESUME: 1122 ieee80211_scan_state_resume(local, &next_delay); 1123 break; 1124 case SCAN_ABORT: 1125 aborted = true; 1126 goto out_complete; 1127 } 1128 } while (next_delay == 0); 1129 1130 ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); 1131 goto out; 1132 1133 out_complete: 1134 __ieee80211_scan_completed(&local->hw, aborted); 1135 out: 1136 mutex_unlock(&local->mtx); 1137 } 1138 1139 int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, 1140 struct cfg80211_scan_request *req) 1141 { 1142 int res; 1143 1144 mutex_lock(&sdata->local->mtx); 1145 res = __ieee80211_start_scan(sdata, req); 1146 mutex_unlock(&sdata->local->mtx); 1147 1148 return res; 1149 } 1150 1151 int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata, 1152 const u8 *ssid, u8 ssid_len, 1153 struct ieee80211_channel **channels, 1154 unsigned int n_channels, 1155 enum nl80211_bss_scan_width scan_width) 1156 { 1157 struct ieee80211_local *local = sdata->local; 1158 int ret = -EBUSY, i, n_ch = 0; 1159 enum nl80211_band band; 1160 1161 mutex_lock(&local->mtx); 1162 1163 /* busy scanning */ 1164 if (local->scan_req) 1165 goto unlock; 1166 1167 /* fill internal scan request */ 1168 if (!channels) { 1169 int max_n; 1170 1171 for (band = 0; band < NUM_NL80211_BANDS; band++) { 1172 if (!local->hw.wiphy->bands[band] || 1173 band == NL80211_BAND_6GHZ) 1174 continue; 1175 1176 max_n = local->hw.wiphy->bands[band]->n_channels; 1177 for (i = 0; i < max_n; i++) { 1178 struct ieee80211_channel *tmp_ch = 1179 &local->hw.wiphy->bands[band]->channels[i]; 1180 1181 if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR | 1182 IEEE80211_CHAN_DISABLED)) 1183 continue; 1184 1185 local->int_scan_req->channels[n_ch] = tmp_ch; 1186 n_ch++; 1187 } 1188 } 1189 1190 if (WARN_ON_ONCE(n_ch == 0)) 1191 goto unlock; 1192 1193 local->int_scan_req->n_channels = n_ch; 1194 } else { 1195 for (i = 0; i < n_channels; i++) { 1196 if (channels[i]->flags & (IEEE80211_CHAN_NO_IR | 1197 IEEE80211_CHAN_DISABLED)) 1198 continue; 1199 1200 local->int_scan_req->channels[n_ch] = channels[i]; 1201 n_ch++; 1202 } 1203 1204 if (WARN_ON_ONCE(n_ch == 0)) 1205 goto unlock; 1206 1207 local->int_scan_req->n_channels = n_ch; 1208 } 1209 1210 local->int_scan_req->ssids = &local->scan_ssid; 1211 local->int_scan_req->n_ssids = 1; 1212 local->int_scan_req->scan_width = scan_width; 1213 memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); 1214 local->int_scan_req->ssids[0].ssid_len = ssid_len; 1215 1216 ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); 1217 unlock: 1218 mutex_unlock(&local->mtx); 1219 return ret; 1220 } 1221 1222 /* 1223 * Only call this function when a scan can't be queued -- under RTNL. 1224 */ 1225 void ieee80211_scan_cancel(struct ieee80211_local *local) 1226 { 1227 /* 1228 * We are canceling software scan, or deferred scan that was not 1229 * yet really started (see __ieee80211_start_scan ). 1230 * 1231 * Regarding hardware scan: 1232 * - we can not call __ieee80211_scan_completed() as when 1233 * SCAN_HW_SCANNING bit is set this function change 1234 * local->hw_scan_req to operate on 5G band, what race with 1235 * driver which can use local->hw_scan_req 1236 * 1237 * - we can not cancel scan_work since driver can schedule it 1238 * by ieee80211_scan_completed(..., true) to finish scan 1239 * 1240 * Hence we only call the cancel_hw_scan() callback, but the low-level 1241 * driver is still responsible for calling ieee80211_scan_completed() 1242 * after the scan was completed/aborted. 1243 */ 1244 1245 mutex_lock(&local->mtx); 1246 if (!local->scan_req) 1247 goto out; 1248 1249 /* 1250 * We have a scan running and the driver already reported completion, 1251 * but the worker hasn't run yet or is stuck on the mutex - mark it as 1252 * cancelled. 1253 */ 1254 if (test_bit(SCAN_HW_SCANNING, &local->scanning) && 1255 test_bit(SCAN_COMPLETED, &local->scanning)) { 1256 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1257 goto out; 1258 } 1259 1260 if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { 1261 /* 1262 * Make sure that __ieee80211_scan_completed doesn't trigger a 1263 * scan on another band. 1264 */ 1265 set_bit(SCAN_HW_CANCELLED, &local->scanning); 1266 if (local->ops->cancel_hw_scan) 1267 drv_cancel_hw_scan(local, 1268 rcu_dereference_protected(local->scan_sdata, 1269 lockdep_is_held(&local->mtx))); 1270 goto out; 1271 } 1272 1273 /* 1274 * If the work is currently running, it must be blocked on 1275 * the mutex, but we'll set scan_sdata = NULL and it'll 1276 * simply exit once it acquires the mutex. 1277 */ 1278 cancel_delayed_work(&local->scan_work); 1279 /* and clean up */ 1280 memset(&local->scan_info, 0, sizeof(local->scan_info)); 1281 __ieee80211_scan_completed(&local->hw, true); 1282 out: 1283 mutex_unlock(&local->mtx); 1284 } 1285 1286 int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1287 struct cfg80211_sched_scan_request *req) 1288 { 1289 struct ieee80211_local *local = sdata->local; 1290 struct ieee80211_scan_ies sched_scan_ies = {}; 1291 struct cfg80211_chan_def chandef; 1292 int ret, i, iebufsz, num_bands = 0; 1293 u32 rate_masks[NUM_NL80211_BANDS] = {}; 1294 u8 bands_used = 0; 1295 u8 *ie; 1296 u32 flags = 0; 1297 1298 iebufsz = local->scan_ies_len + req->ie_len; 1299 1300 lockdep_assert_held(&local->mtx); 1301 1302 if (!local->ops->sched_scan_start) 1303 return -ENOTSUPP; 1304 1305 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1306 if (local->hw.wiphy->bands[i]) { 1307 bands_used |= BIT(i); 1308 rate_masks[i] = (u32) -1; 1309 num_bands++; 1310 } 1311 } 1312 1313 if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT) 1314 flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT; 1315 1316 ie = kcalloc(iebufsz, num_bands, GFP_KERNEL); 1317 if (!ie) { 1318 ret = -ENOMEM; 1319 goto out; 1320 } 1321 1322 ieee80211_prepare_scan_chandef(&chandef, req->scan_width); 1323 1324 ieee80211_build_preq_ies(sdata, ie, num_bands * iebufsz, 1325 &sched_scan_ies, req->ie, 1326 req->ie_len, bands_used, rate_masks, &chandef, 1327 flags); 1328 1329 ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies); 1330 if (ret == 0) { 1331 rcu_assign_pointer(local->sched_scan_sdata, sdata); 1332 rcu_assign_pointer(local->sched_scan_req, req); 1333 } 1334 1335 kfree(ie); 1336 1337 out: 1338 if (ret) { 1339 /* Clean in case of failure after HW restart or upon resume. */ 1340 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1341 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1342 } 1343 1344 return ret; 1345 } 1346 1347 int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, 1348 struct cfg80211_sched_scan_request *req) 1349 { 1350 struct ieee80211_local *local = sdata->local; 1351 int ret; 1352 1353 mutex_lock(&local->mtx); 1354 1355 if (rcu_access_pointer(local->sched_scan_sdata)) { 1356 mutex_unlock(&local->mtx); 1357 return -EBUSY; 1358 } 1359 1360 ret = __ieee80211_request_sched_scan_start(sdata, req); 1361 1362 mutex_unlock(&local->mtx); 1363 return ret; 1364 } 1365 1366 int ieee80211_request_sched_scan_stop(struct ieee80211_local *local) 1367 { 1368 struct ieee80211_sub_if_data *sched_scan_sdata; 1369 int ret = -ENOENT; 1370 1371 mutex_lock(&local->mtx); 1372 1373 if (!local->ops->sched_scan_stop) { 1374 ret = -ENOTSUPP; 1375 goto out; 1376 } 1377 1378 /* We don't want to restart sched scan anymore. */ 1379 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1380 1381 sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata, 1382 lockdep_is_held(&local->mtx)); 1383 if (sched_scan_sdata) { 1384 ret = drv_sched_scan_stop(local, sched_scan_sdata); 1385 if (!ret) 1386 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1387 } 1388 out: 1389 mutex_unlock(&local->mtx); 1390 1391 return ret; 1392 } 1393 1394 void ieee80211_sched_scan_results(struct ieee80211_hw *hw) 1395 { 1396 struct ieee80211_local *local = hw_to_local(hw); 1397 1398 trace_api_sched_scan_results(local); 1399 1400 cfg80211_sched_scan_results(hw->wiphy, 0); 1401 } 1402 EXPORT_SYMBOL(ieee80211_sched_scan_results); 1403 1404 void ieee80211_sched_scan_end(struct ieee80211_local *local) 1405 { 1406 mutex_lock(&local->mtx); 1407 1408 if (!rcu_access_pointer(local->sched_scan_sdata)) { 1409 mutex_unlock(&local->mtx); 1410 return; 1411 } 1412 1413 RCU_INIT_POINTER(local->sched_scan_sdata, NULL); 1414 1415 /* If sched scan was aborted by the driver. */ 1416 RCU_INIT_POINTER(local->sched_scan_req, NULL); 1417 1418 mutex_unlock(&local->mtx); 1419 1420 cfg80211_sched_scan_stopped(local->hw.wiphy, 0); 1421 } 1422 1423 void ieee80211_sched_scan_stopped_work(struct work_struct *work) 1424 { 1425 struct ieee80211_local *local = 1426 container_of(work, struct ieee80211_local, 1427 sched_scan_stopped_work); 1428 1429 ieee80211_sched_scan_end(local); 1430 } 1431 1432 void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) 1433 { 1434 struct ieee80211_local *local = hw_to_local(hw); 1435 1436 trace_api_sched_scan_stopped(local); 1437 1438 /* 1439 * this shouldn't really happen, so for simplicity 1440 * simply ignore it, and let mac80211 reconfigure 1441 * the sched scan later on. 1442 */ 1443 if (local->in_reconfig) 1444 return; 1445 1446 schedule_work(&local->sched_scan_stopped_work); 1447 } 1448 EXPORT_SYMBOL(ieee80211_sched_scan_stopped); 1449