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