1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * MLO link handling 4 * 5 * Copyright (C) 2022-2024 Intel Corporation 6 */ 7 #include <linux/slab.h> 8 #include <linux/kernel.h> 9 #include <net/mac80211.h> 10 #include "ieee80211_i.h" 11 #include "driver-ops.h" 12 #include "key.h" 13 #include "debugfs_netdev.h" 14 15 static void ieee80211_update_apvlan_links(struct ieee80211_sub_if_data *sdata) 16 { 17 struct ieee80211_sub_if_data *vlan; 18 struct ieee80211_link_data *link; 19 u16 ap_bss_links = sdata->vif.valid_links; 20 u16 new_links, vlan_links; 21 unsigned long add; 22 23 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) { 24 int link_id; 25 26 if (!vlan) 27 continue; 28 29 /* No support for 4addr with MLO yet */ 30 if (vlan->wdev.use_4addr) 31 return; 32 33 vlan_links = vlan->vif.valid_links; 34 35 new_links = ap_bss_links; 36 37 add = new_links & ~vlan_links; 38 if (!add) 39 continue; 40 41 ieee80211_vif_set_links(vlan, add, 0); 42 43 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 44 link = sdata_dereference(vlan->link[link_id], vlan); 45 ieee80211_link_vlan_copy_chanctx(link); 46 } 47 } 48 } 49 50 void ieee80211_apvlan_link_setup(struct ieee80211_sub_if_data *sdata) 51 { 52 struct ieee80211_sub_if_data *ap_bss = container_of(sdata->bss, 53 struct ieee80211_sub_if_data, u.ap); 54 u16 new_links = ap_bss->vif.valid_links; 55 unsigned long add; 56 int link_id; 57 58 if (!ap_bss->vif.valid_links) 59 return; 60 61 add = new_links; 62 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 63 sdata->wdev.valid_links |= BIT(link_id); 64 ether_addr_copy(sdata->wdev.links[link_id].addr, 65 ap_bss->wdev.links[link_id].addr); 66 } 67 68 ieee80211_vif_set_links(sdata, new_links, 0); 69 } 70 71 void ieee80211_apvlan_link_clear(struct ieee80211_sub_if_data *sdata) 72 { 73 if (!sdata->wdev.valid_links) 74 return; 75 76 sdata->wdev.valid_links = 0; 77 ieee80211_vif_clear_links(sdata); 78 } 79 80 void ieee80211_link_setup(struct ieee80211_link_data *link) 81 { 82 if (link->sdata->vif.type == NL80211_IFTYPE_STATION) 83 ieee80211_mgd_setup_link(link); 84 } 85 86 void ieee80211_link_init(struct ieee80211_sub_if_data *sdata, 87 int link_id, 88 struct ieee80211_link_data *link, 89 struct ieee80211_bss_conf *link_conf) 90 { 91 bool deflink = link_id < 0; 92 93 if (link_id < 0) 94 link_id = 0; 95 96 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) { 97 struct ieee80211_sub_if_data *ap_bss; 98 struct ieee80211_bss_conf *ap_bss_conf; 99 100 ap_bss = container_of(sdata->bss, 101 struct ieee80211_sub_if_data, u.ap); 102 ap_bss_conf = sdata_dereference(ap_bss->vif.link_conf[link_id], 103 ap_bss); 104 memcpy(link_conf, ap_bss_conf, sizeof(*link_conf)); 105 } 106 107 link->sdata = sdata; 108 link->link_id = link_id; 109 link->conf = link_conf; 110 link_conf->link_id = link_id; 111 link_conf->vif = &sdata->vif; 112 link->ap_power_level = IEEE80211_UNSET_POWER_LEVEL; 113 link->user_power_level = sdata->local->user_power_level; 114 link_conf->txpower = INT_MIN; 115 116 wiphy_work_init(&link->csa.finalize_work, 117 ieee80211_csa_finalize_work); 118 wiphy_work_init(&link->color_change_finalize_work, 119 ieee80211_color_change_finalize_work); 120 wiphy_delayed_work_init(&link->color_collision_detect_work, 121 ieee80211_color_collision_detection_work); 122 INIT_LIST_HEAD(&link->assigned_chanctx_list); 123 INIT_LIST_HEAD(&link->reserved_chanctx_list); 124 wiphy_delayed_work_init(&link->dfs_cac_timer_work, 125 ieee80211_dfs_cac_timer_work); 126 127 if (!deflink) { 128 switch (sdata->vif.type) { 129 case NL80211_IFTYPE_AP: 130 case NL80211_IFTYPE_AP_VLAN: 131 ether_addr_copy(link_conf->addr, 132 sdata->wdev.links[link_id].addr); 133 link_conf->bssid = link_conf->addr; 134 WARN_ON(!(sdata->wdev.valid_links & BIT(link_id))); 135 break; 136 case NL80211_IFTYPE_STATION: 137 /* station sets the bssid in ieee80211_mgd_setup_link */ 138 break; 139 default: 140 WARN_ON(1); 141 } 142 143 ieee80211_link_debugfs_add(link); 144 } 145 146 rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf); 147 rcu_assign_pointer(sdata->link[link_id], link); 148 } 149 150 void ieee80211_link_stop(struct ieee80211_link_data *link) 151 { 152 if (link->sdata->vif.type == NL80211_IFTYPE_STATION) 153 ieee80211_mgd_stop_link(link); 154 155 wiphy_delayed_work_cancel(link->sdata->local->hw.wiphy, 156 &link->color_collision_detect_work); 157 wiphy_work_cancel(link->sdata->local->hw.wiphy, 158 &link->color_change_finalize_work); 159 wiphy_work_cancel(link->sdata->local->hw.wiphy, 160 &link->csa.finalize_work); 161 162 if (link->sdata->wdev.links[link->link_id].cac_started) { 163 wiphy_delayed_work_cancel(link->sdata->local->hw.wiphy, 164 &link->dfs_cac_timer_work); 165 cfg80211_cac_event(link->sdata->dev, 166 &link->conf->chanreq.oper, 167 NL80211_RADAR_CAC_ABORTED, 168 GFP_KERNEL, link->link_id); 169 } 170 171 ieee80211_link_release_channel(link); 172 } 173 174 struct link_container { 175 struct ieee80211_link_data data; 176 struct ieee80211_bss_conf conf; 177 }; 178 179 static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata, 180 struct link_container **links, u16 mask) 181 { 182 struct ieee80211_link_data *link; 183 LIST_HEAD(keys); 184 unsigned int link_id; 185 186 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 187 if (!(mask & BIT(link_id))) 188 continue; 189 link = &links[link_id]->data; 190 if (link_id == 0 && !link) 191 link = &sdata->deflink; 192 if (WARN_ON(!link)) 193 continue; 194 ieee80211_remove_link_keys(link, &keys); 195 ieee80211_link_debugfs_remove(link); 196 ieee80211_link_stop(link); 197 } 198 199 synchronize_rcu(); 200 201 ieee80211_free_key_list(sdata->local, &keys); 202 } 203 204 static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata, 205 struct link_container **links) 206 { 207 unsigned int link_id; 208 209 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) 210 kfree(links[link_id]); 211 } 212 213 static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata) 214 { 215 unsigned int i, j; 216 217 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) { 218 struct ieee80211_link_data *link1; 219 220 link1 = sdata_dereference(sdata->link[i], sdata); 221 if (!link1) 222 continue; 223 for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) { 224 struct ieee80211_link_data *link2; 225 226 link2 = sdata_dereference(sdata->link[j], sdata); 227 if (!link2) 228 continue; 229 230 if (ether_addr_equal(link1->conf->addr, 231 link2->conf->addr)) 232 return -EALREADY; 233 } 234 } 235 236 return 0; 237 } 238 239 static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata, 240 u16 valid_links, u16 dormant_links) 241 { 242 sdata->vif.valid_links = valid_links; 243 sdata->vif.dormant_links = dormant_links; 244 245 if (!valid_links || 246 WARN((~valid_links & dormant_links) || 247 !(valid_links & ~dormant_links), 248 "Invalid links: valid=0x%x, dormant=0x%x", 249 valid_links, dormant_links)) { 250 sdata->vif.active_links = 0; 251 sdata->vif.dormant_links = 0; 252 return; 253 } 254 255 switch (sdata->vif.type) { 256 case NL80211_IFTYPE_AP: 257 case NL80211_IFTYPE_AP_VLAN: 258 /* in an AP all links are always active */ 259 sdata->vif.active_links = valid_links; 260 261 /* AP links are not expected to be disabled */ 262 WARN_ON(dormant_links); 263 break; 264 case NL80211_IFTYPE_STATION: 265 if (sdata->vif.active_links) 266 break; 267 sdata->vif.active_links = valid_links & ~dormant_links; 268 WARN_ON(hweight16(sdata->vif.active_links) > 1); 269 break; 270 default: 271 WARN_ON(1); 272 } 273 } 274 275 static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata, 276 struct link_container **to_free, 277 u16 new_links, u16 dormant_links) 278 { 279 u16 old_links = sdata->vif.valid_links; 280 u16 old_active = sdata->vif.active_links; 281 unsigned long add = new_links & ~old_links; 282 unsigned long rem = old_links & ~new_links; 283 unsigned int link_id; 284 int ret; 285 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link; 286 struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS]; 287 struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS]; 288 bool use_deflink = old_links == 0; /* set for error case */ 289 290 lockdep_assert_wiphy(sdata->local->hw.wiphy); 291 292 memset(to_free, 0, sizeof(links)); 293 294 if (old_links == new_links && dormant_links == sdata->vif.dormant_links) 295 return 0; 296 297 /* if there were no old links, need to clear the pointers to deflink */ 298 if (!old_links) 299 rem |= BIT(0); 300 301 /* allocate new link structures first */ 302 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 303 link = kzalloc(sizeof(*link), GFP_KERNEL); 304 if (!link) { 305 ret = -ENOMEM; 306 goto free; 307 } 308 links[link_id] = link; 309 } 310 311 /* keep track of the old pointers for the driver */ 312 BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf)); 313 memcpy(old, sdata->vif.link_conf, sizeof(old)); 314 /* and for us in error cases */ 315 BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link)); 316 memcpy(old_data, sdata->link, sizeof(old_data)); 317 318 /* grab old links to free later */ 319 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 320 if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) { 321 /* 322 * we must have allocated the data through this path so 323 * we know we can free both at the same time 324 */ 325 to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]), 326 typeof(*links[link_id]), 327 data); 328 } 329 330 RCU_INIT_POINTER(sdata->link[link_id], NULL); 331 RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL); 332 } 333 334 if (!old_links) 335 ieee80211_debugfs_recreate_netdev(sdata, true); 336 337 /* link them into data structures */ 338 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 339 WARN_ON(!use_deflink && 340 rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink); 341 342 link = links[link_id]; 343 ieee80211_link_init(sdata, link_id, &link->data, &link->conf); 344 ieee80211_link_setup(&link->data); 345 } 346 347 if (new_links == 0) 348 ieee80211_link_init(sdata, -1, &sdata->deflink, 349 &sdata->vif.bss_conf); 350 351 ret = ieee80211_check_dup_link_addrs(sdata); 352 if (!ret) { 353 /* for keys we will not be able to undo this */ 354 ieee80211_tear_down_links(sdata, to_free, rem); 355 356 ieee80211_set_vif_links_bitmaps(sdata, new_links, dormant_links); 357 358 /* tell the driver */ 359 if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN) 360 ret = drv_change_vif_links(sdata->local, sdata, 361 old_links & old_active, 362 new_links & sdata->vif.active_links, 363 old); 364 if (!new_links) 365 ieee80211_debugfs_recreate_netdev(sdata, false); 366 367 if (sdata->vif.type == NL80211_IFTYPE_AP) 368 ieee80211_update_apvlan_links(sdata); 369 } 370 371 if (ret) { 372 /* restore config */ 373 memcpy(sdata->link, old_data, sizeof(old_data)); 374 memcpy(sdata->vif.link_conf, old, sizeof(old)); 375 ieee80211_set_vif_links_bitmaps(sdata, old_links, dormant_links); 376 /* and free (only) the newly allocated links */ 377 memset(to_free, 0, sizeof(links)); 378 goto free; 379 } 380 381 /* use deflink/bss_conf again if and only if there are no more links */ 382 use_deflink = new_links == 0; 383 384 goto deinit; 385 free: 386 /* if we failed during allocation, only free all */ 387 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 388 kfree(links[link_id]); 389 links[link_id] = NULL; 390 } 391 deinit: 392 if (use_deflink) 393 ieee80211_link_init(sdata, -1, &sdata->deflink, 394 &sdata->vif.bss_conf); 395 return ret; 396 } 397 398 int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata, 399 u16 new_links, u16 dormant_links) 400 { 401 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS]; 402 int ret; 403 404 ret = ieee80211_vif_update_links(sdata, links, new_links, 405 dormant_links); 406 ieee80211_free_links(sdata, links); 407 408 return ret; 409 } 410 411 static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata, 412 u16 active_links) 413 { 414 struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS]; 415 struct ieee80211_local *local = sdata->local; 416 u16 old_active = sdata->vif.active_links; 417 unsigned long rem = old_active & ~active_links; 418 unsigned long add = active_links & ~old_active; 419 struct sta_info *sta; 420 unsigned int link_id; 421 int ret, i; 422 423 if (!ieee80211_sdata_running(sdata)) 424 return -ENETDOWN; 425 426 if (sdata->vif.type != NL80211_IFTYPE_STATION) 427 return -EINVAL; 428 429 if (active_links & ~ieee80211_vif_usable_links(&sdata->vif)) 430 return -EINVAL; 431 432 /* nothing to do */ 433 if (old_active == active_links) 434 return 0; 435 436 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) 437 link_confs[i] = sdata_dereference(sdata->vif.link_conf[i], 438 sdata); 439 440 if (add) { 441 sdata->vif.active_links |= active_links; 442 ret = drv_change_vif_links(local, sdata, 443 old_active, 444 sdata->vif.active_links, 445 link_confs); 446 if (ret) { 447 sdata->vif.active_links = old_active; 448 return ret; 449 } 450 } 451 452 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 453 struct ieee80211_link_data *link; 454 455 link = sdata_dereference(sdata->link[link_id], sdata); 456 457 ieee80211_teardown_tdls_peers(link); 458 459 __ieee80211_link_release_channel(link, true); 460 461 /* 462 * If CSA is (still) active while the link is deactivated, 463 * just schedule the channel switch work for the time we 464 * had previously calculated, and we'll take the process 465 * from there. 466 */ 467 if (link->conf->csa_active) 468 wiphy_delayed_work_queue(local->hw.wiphy, 469 &link->u.mgd.csa.switch_work, 470 link->u.mgd.csa.time - 471 jiffies); 472 } 473 474 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 475 struct ieee80211_link_data *link; 476 477 link = sdata_dereference(sdata->link[link_id], sdata); 478 479 /* 480 * This call really should not fail. Unfortunately, it appears 481 * that this may happen occasionally with some drivers. Should 482 * it happen, we are stuck in a bad place as going backwards is 483 * not really feasible. 484 * 485 * So lets just tell link_use_channel that it must not fail to 486 * assign the channel context (from mac80211's perspective) and 487 * assume the driver is going to trigger a recovery flow if it 488 * had a failure. 489 * That really is not great nor guaranteed to work. But at least 490 * the internal mac80211 state remains consistent and there is 491 * a chance that we can recover. 492 */ 493 ret = _ieee80211_link_use_channel(link, 494 &link->conf->chanreq, 495 IEEE80211_CHANCTX_SHARED, 496 true); 497 WARN_ON_ONCE(ret); 498 499 /* 500 * inform about the link info changed parameters after all 501 * stations are also added 502 */ 503 } 504 505 list_for_each_entry(sta, &local->sta_list, list) { 506 if (sdata != sta->sdata) 507 continue; 508 509 /* this is very temporary, but do it anyway */ 510 __ieee80211_sta_recalc_aggregates(sta, 511 old_active | active_links); 512 513 ret = drv_change_sta_links(local, sdata, &sta->sta, 514 old_active, 515 old_active | active_links); 516 WARN_ON_ONCE(ret); 517 } 518 519 ret = ieee80211_key_switch_links(sdata, rem, add); 520 WARN_ON_ONCE(ret); 521 522 list_for_each_entry(sta, &local->sta_list, list) { 523 if (sdata != sta->sdata) 524 continue; 525 526 __ieee80211_sta_recalc_aggregates(sta, active_links); 527 528 ret = drv_change_sta_links(local, sdata, &sta->sta, 529 old_active | active_links, 530 active_links); 531 WARN_ON_ONCE(ret); 532 533 /* 534 * Do it again, just in case - the driver might very 535 * well have called ieee80211_sta_recalc_aggregates() 536 * from there when filling in the new links, which 537 * would set it wrong since the vif's active links are 538 * not switched yet... 539 */ 540 __ieee80211_sta_recalc_aggregates(sta, active_links); 541 } 542 543 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 544 struct ieee80211_link_data *link; 545 546 link = sdata_dereference(sdata->link[link_id], sdata); 547 548 ieee80211_mgd_set_link_qos_params(link); 549 ieee80211_link_info_change_notify(sdata, link, 550 BSS_CHANGED_ERP_CTS_PROT | 551 BSS_CHANGED_ERP_PREAMBLE | 552 BSS_CHANGED_ERP_SLOT | 553 BSS_CHANGED_HT | 554 BSS_CHANGED_BASIC_RATES | 555 BSS_CHANGED_BSSID | 556 BSS_CHANGED_CQM | 557 BSS_CHANGED_QOS | 558 BSS_CHANGED_TXPOWER | 559 BSS_CHANGED_BANDWIDTH | 560 BSS_CHANGED_TWT | 561 BSS_CHANGED_HE_OBSS_PD | 562 BSS_CHANGED_HE_BSS_COLOR); 563 } 564 565 old_active = sdata->vif.active_links; 566 sdata->vif.active_links = active_links; 567 568 if (rem) { 569 ret = drv_change_vif_links(local, sdata, old_active, 570 active_links, link_confs); 571 WARN_ON_ONCE(ret); 572 } 573 574 return 0; 575 } 576 577 int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links) 578 { 579 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 580 struct ieee80211_local *local = sdata->local; 581 u16 old_active; 582 int ret; 583 584 lockdep_assert_wiphy(local->hw.wiphy); 585 586 if (WARN_ON(!active_links)) 587 return -EINVAL; 588 589 old_active = sdata->vif.active_links; 590 if (old_active == active_links) 591 return 0; 592 593 if (!drv_can_activate_links(local, sdata, active_links)) 594 return -EINVAL; 595 596 if (old_active & active_links) { 597 /* 598 * if there's at least one link that stays active across 599 * the change then switch to it (to those) first, and 600 * then enable the additional links 601 */ 602 ret = _ieee80211_set_active_links(sdata, 603 old_active & active_links); 604 if (!ret) 605 ret = _ieee80211_set_active_links(sdata, active_links); 606 } else { 607 /* otherwise switch directly */ 608 ret = _ieee80211_set_active_links(sdata, active_links); 609 } 610 611 return ret; 612 } 613 EXPORT_SYMBOL_GPL(ieee80211_set_active_links); 614 615 void ieee80211_set_active_links_async(struct ieee80211_vif *vif, 616 u16 active_links) 617 { 618 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 619 620 if (WARN_ON(!active_links)) 621 return; 622 623 if (!ieee80211_sdata_running(sdata)) 624 return; 625 626 if (sdata->vif.type != NL80211_IFTYPE_STATION) 627 return; 628 629 if (active_links & ~ieee80211_vif_usable_links(&sdata->vif)) 630 return; 631 632 /* nothing to do */ 633 if (sdata->vif.active_links == active_links) 634 return; 635 636 sdata->desired_active_links = active_links; 637 wiphy_work_queue(sdata->local->hw.wiphy, &sdata->activate_links_work); 638 } 639 EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async); 640