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