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