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