1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * MLO link handling 4 * 5 * Copyright (C) 2022 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 14 void ieee80211_link_setup(struct ieee80211_link_data *link) 15 { 16 if (link->sdata->vif.type == NL80211_IFTYPE_STATION) 17 ieee80211_mgd_setup_link(link); 18 } 19 20 void ieee80211_link_init(struct ieee80211_sub_if_data *sdata, 21 int link_id, 22 struct ieee80211_link_data *link, 23 struct ieee80211_bss_conf *link_conf) 24 { 25 bool deflink = link_id < 0; 26 27 if (link_id < 0) 28 link_id = 0; 29 30 rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf); 31 rcu_assign_pointer(sdata->link[link_id], link); 32 33 link->sdata = sdata; 34 link->link_id = link_id; 35 link->conf = link_conf; 36 link_conf->link_id = link_id; 37 38 INIT_WORK(&link->csa_finalize_work, 39 ieee80211_csa_finalize_work); 40 INIT_WORK(&link->color_change_finalize_work, 41 ieee80211_color_change_finalize_work); 42 INIT_DELAYED_WORK(&link->color_collision_detect_work, 43 ieee80211_color_collision_detection_work); 44 INIT_LIST_HEAD(&link->assigned_chanctx_list); 45 INIT_LIST_HEAD(&link->reserved_chanctx_list); 46 INIT_DELAYED_WORK(&link->dfs_cac_timer_work, 47 ieee80211_dfs_cac_timer_work); 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 } 65 66 void ieee80211_link_stop(struct ieee80211_link_data *link) 67 { 68 if (link->sdata->vif.type == NL80211_IFTYPE_STATION) 69 ieee80211_mgd_stop_link(link); 70 71 cancel_delayed_work_sync(&link->color_collision_detect_work); 72 ieee80211_link_release_channel(link); 73 } 74 75 struct link_container { 76 struct ieee80211_link_data data; 77 struct ieee80211_bss_conf conf; 78 }; 79 80 static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata, 81 struct link_container **links, u16 mask) 82 { 83 struct ieee80211_link_data *link; 84 LIST_HEAD(keys); 85 unsigned int link_id; 86 87 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 88 if (!(mask & BIT(link_id))) 89 continue; 90 link = &links[link_id]->data; 91 if (link_id == 0 && !link) 92 link = &sdata->deflink; 93 if (WARN_ON(!link)) 94 continue; 95 ieee80211_remove_link_keys(link, &keys); 96 ieee80211_link_stop(link); 97 } 98 99 synchronize_rcu(); 100 101 ieee80211_free_key_list(sdata->local, &keys); 102 } 103 104 static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata, 105 struct link_container **links) 106 { 107 unsigned int link_id; 108 109 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) 110 kfree(links[link_id]); 111 } 112 113 static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata) 114 { 115 unsigned int i, j; 116 117 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) { 118 struct ieee80211_link_data *link1; 119 120 link1 = sdata_dereference(sdata->link[i], sdata); 121 if (!link1) 122 continue; 123 for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) { 124 struct ieee80211_link_data *link2; 125 126 link2 = sdata_dereference(sdata->link[j], sdata); 127 if (!link2) 128 continue; 129 130 if (ether_addr_equal(link1->conf->addr, 131 link2->conf->addr)) 132 return -EALREADY; 133 } 134 } 135 136 return 0; 137 } 138 139 static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata, 140 u16 links) 141 { 142 sdata->vif.valid_links = links; 143 144 if (!links) { 145 sdata->vif.active_links = 0; 146 return; 147 } 148 149 switch (sdata->vif.type) { 150 case NL80211_IFTYPE_AP: 151 /* in an AP all links are always active */ 152 sdata->vif.active_links = links; 153 break; 154 case NL80211_IFTYPE_STATION: 155 if (sdata->vif.active_links) 156 break; 157 WARN_ON(hweight16(links) > 1); 158 sdata->vif.active_links = links; 159 break; 160 default: 161 WARN_ON(1); 162 } 163 } 164 165 static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata, 166 struct link_container **to_free, 167 u16 new_links) 168 { 169 u16 old_links = sdata->vif.valid_links; 170 u16 old_active = sdata->vif.active_links; 171 unsigned long add = new_links & ~old_links; 172 unsigned long rem = old_links & ~new_links; 173 unsigned int link_id; 174 int ret; 175 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link; 176 struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS]; 177 struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS]; 178 bool use_deflink = old_links == 0; /* set for error case */ 179 180 sdata_assert_lock(sdata); 181 182 memset(to_free, 0, sizeof(links)); 183 184 if (old_links == new_links) 185 return 0; 186 187 /* if there were no old links, need to clear the pointers to deflink */ 188 if (!old_links) 189 rem |= BIT(0); 190 191 /* allocate new link structures first */ 192 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 193 link = kzalloc(sizeof(*link), GFP_KERNEL); 194 if (!link) { 195 ret = -ENOMEM; 196 goto free; 197 } 198 links[link_id] = link; 199 } 200 201 /* keep track of the old pointers for the driver */ 202 BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf)); 203 memcpy(old, sdata->vif.link_conf, sizeof(old)); 204 /* and for us in error cases */ 205 BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link)); 206 memcpy(old_data, sdata->link, sizeof(old_data)); 207 208 /* grab old links to free later */ 209 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 210 if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) { 211 /* 212 * we must have allocated the data through this path so 213 * we know we can free both at the same time 214 */ 215 to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]), 216 typeof(*links[link_id]), 217 data); 218 } 219 220 RCU_INIT_POINTER(sdata->link[link_id], NULL); 221 RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL); 222 } 223 224 /* link them into data structures */ 225 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 226 WARN_ON(!use_deflink && 227 rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink); 228 229 link = links[link_id]; 230 ieee80211_link_init(sdata, link_id, &link->data, &link->conf); 231 ieee80211_link_setup(&link->data); 232 } 233 234 if (new_links == 0) 235 ieee80211_link_init(sdata, -1, &sdata->deflink, 236 &sdata->vif.bss_conf); 237 238 ret = ieee80211_check_dup_link_addrs(sdata); 239 if (!ret) { 240 /* for keys we will not be able to undo this */ 241 ieee80211_tear_down_links(sdata, to_free, rem); 242 243 ieee80211_set_vif_links_bitmaps(sdata, new_links); 244 245 /* tell the driver */ 246 ret = drv_change_vif_links(sdata->local, sdata, 247 old_links & old_active, 248 new_links & sdata->vif.active_links, 249 old); 250 } 251 252 if (ret) { 253 /* restore config */ 254 memcpy(sdata->link, old_data, sizeof(old_data)); 255 memcpy(sdata->vif.link_conf, old, sizeof(old)); 256 ieee80211_set_vif_links_bitmaps(sdata, old_links); 257 /* and free (only) the newly allocated links */ 258 memset(to_free, 0, sizeof(links)); 259 goto free; 260 } 261 262 /* use deflink/bss_conf again if and only if there are no more links */ 263 use_deflink = new_links == 0; 264 265 goto deinit; 266 free: 267 /* if we failed during allocation, only free all */ 268 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 269 kfree(links[link_id]); 270 links[link_id] = NULL; 271 } 272 deinit: 273 if (use_deflink) 274 ieee80211_link_init(sdata, -1, &sdata->deflink, 275 &sdata->vif.bss_conf); 276 return ret; 277 } 278 279 int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata, 280 u16 new_links) 281 { 282 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS]; 283 int ret; 284 285 ret = ieee80211_vif_update_links(sdata, links, new_links); 286 ieee80211_free_links(sdata, links); 287 288 return ret; 289 } 290 291 void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata) 292 { 293 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS]; 294 295 /* 296 * The locking here is different because when we free links 297 * in the station case we need to be able to cancel_work_sync() 298 * something that also takes the lock. 299 */ 300 301 sdata_lock(sdata); 302 ieee80211_vif_update_links(sdata, links, 0); 303 sdata_unlock(sdata); 304 305 ieee80211_free_links(sdata, links); 306 } 307 308 static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata, 309 u16 active_links) 310 { 311 struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS]; 312 struct ieee80211_local *local = sdata->local; 313 u16 old_active = sdata->vif.active_links; 314 unsigned long rem = old_active & ~active_links; 315 unsigned long add = active_links & ~old_active; 316 struct sta_info *sta; 317 unsigned int link_id; 318 int ret, i; 319 320 if (!ieee80211_sdata_running(sdata)) 321 return -ENETDOWN; 322 323 if (sdata->vif.type != NL80211_IFTYPE_STATION) 324 return -EINVAL; 325 326 /* cannot activate links that don't exist */ 327 if (active_links & ~sdata->vif.valid_links) 328 return -EINVAL; 329 330 /* nothing to do */ 331 if (old_active == active_links) 332 return 0; 333 334 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) 335 link_confs[i] = sdata_dereference(sdata->vif.link_conf[i], 336 sdata); 337 338 if (add) { 339 sdata->vif.active_links |= active_links; 340 ret = drv_change_vif_links(local, sdata, 341 old_active, 342 sdata->vif.active_links, 343 link_confs); 344 if (ret) { 345 sdata->vif.active_links = old_active; 346 return ret; 347 } 348 } 349 350 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 351 struct ieee80211_link_data *link; 352 353 link = sdata_dereference(sdata->link[link_id], sdata); 354 355 /* FIXME: kill TDLS connections on the link */ 356 357 ieee80211_link_release_channel(link); 358 } 359 360 list_for_each_entry(sta, &local->sta_list, list) { 361 if (sdata != sta->sdata) 362 continue; 363 364 /* this is very temporary, but do it anyway */ 365 __ieee80211_sta_recalc_aggregates(sta, 366 old_active | active_links); 367 368 ret = drv_change_sta_links(local, sdata, &sta->sta, 369 old_active, 370 old_active | active_links); 371 WARN_ON_ONCE(ret); 372 } 373 374 ret = ieee80211_key_switch_links(sdata, rem, add); 375 WARN_ON_ONCE(ret); 376 377 list_for_each_entry(sta, &local->sta_list, list) { 378 if (sdata != sta->sdata) 379 continue; 380 381 __ieee80211_sta_recalc_aggregates(sta, active_links); 382 383 ret = drv_change_sta_links(local, sdata, &sta->sta, 384 old_active | active_links, 385 active_links); 386 WARN_ON_ONCE(ret); 387 388 /* 389 * Do it again, just in case - the driver might very 390 * well have called ieee80211_sta_recalc_aggregates() 391 * from there when filling in the new links, which 392 * would set it wrong since the vif's active links are 393 * not switched yet... 394 */ 395 __ieee80211_sta_recalc_aggregates(sta, active_links); 396 } 397 398 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 399 struct ieee80211_link_data *link; 400 401 link = sdata_dereference(sdata->link[link_id], sdata); 402 403 ret = ieee80211_link_use_channel(link, &link->conf->chandef, 404 IEEE80211_CHANCTX_SHARED); 405 WARN_ON_ONCE(ret); 406 407 ieee80211_link_info_change_notify(sdata, link, 408 BSS_CHANGED_ERP_CTS_PROT | 409 BSS_CHANGED_ERP_PREAMBLE | 410 BSS_CHANGED_ERP_SLOT | 411 BSS_CHANGED_HT | 412 BSS_CHANGED_BASIC_RATES | 413 BSS_CHANGED_BSSID | 414 BSS_CHANGED_CQM | 415 BSS_CHANGED_QOS | 416 BSS_CHANGED_TXPOWER | 417 BSS_CHANGED_BANDWIDTH | 418 BSS_CHANGED_TWT | 419 BSS_CHANGED_HE_OBSS_PD | 420 BSS_CHANGED_HE_BSS_COLOR); 421 ieee80211_mgd_set_link_qos_params(link); 422 } 423 424 old_active = sdata->vif.active_links; 425 sdata->vif.active_links = active_links; 426 427 if (rem) { 428 ret = drv_change_vif_links(local, sdata, old_active, 429 active_links, link_confs); 430 WARN_ON_ONCE(ret); 431 } 432 433 return 0; 434 } 435 436 int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links) 437 { 438 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 439 struct ieee80211_local *local = sdata->local; 440 u16 old_active; 441 int ret; 442 443 sdata_lock(sdata); 444 mutex_lock(&local->sta_mtx); 445 mutex_lock(&local->mtx); 446 mutex_lock(&local->key_mtx); 447 old_active = sdata->vif.active_links; 448 if (old_active & active_links) { 449 /* 450 * if there's at least one link that stays active across 451 * the change then switch to it (to those) first, and 452 * then enable the additional links 453 */ 454 ret = _ieee80211_set_active_links(sdata, 455 old_active & active_links); 456 if (!ret) 457 ret = _ieee80211_set_active_links(sdata, active_links); 458 } else { 459 /* otherwise switch directly */ 460 ret = _ieee80211_set_active_links(sdata, active_links); 461 } 462 mutex_unlock(&local->key_mtx); 463 mutex_unlock(&local->mtx); 464 mutex_unlock(&local->sta_mtx); 465 sdata_unlock(sdata); 466 467 return ret; 468 } 469 EXPORT_SYMBOL_GPL(ieee80211_set_active_links); 470 471 void ieee80211_set_active_links_async(struct ieee80211_vif *vif, 472 u16 active_links) 473 { 474 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 475 476 if (!ieee80211_sdata_running(sdata)) 477 return; 478 479 if (sdata->vif.type != NL80211_IFTYPE_STATION) 480 return; 481 482 /* cannot activate links that don't exist */ 483 if (active_links & ~sdata->vif.valid_links) 484 return; 485 486 /* nothing to do */ 487 if (sdata->vif.active_links == active_links) 488 return; 489 490 sdata->desired_active_links = active_links; 491 schedule_work(&sdata->activate_links_work); 492 } 493 EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async); 494