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