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