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_LIST_HEAD(&link->assigned_chanctx_list); 43 INIT_LIST_HEAD(&link->reserved_chanctx_list); 44 INIT_DELAYED_WORK(&link->dfs_cac_timer_work, 45 ieee80211_dfs_cac_timer_work); 46 47 if (!deflink) { 48 switch (sdata->vif.type) { 49 case NL80211_IFTYPE_AP: 50 ether_addr_copy(link_conf->addr, 51 sdata->wdev.links[link_id].addr); 52 link_conf->bssid = link_conf->addr; 53 WARN_ON(!(sdata->wdev.valid_links & BIT(link_id))); 54 break; 55 case NL80211_IFTYPE_STATION: 56 /* station sets the bssid in ieee80211_mgd_setup_link */ 57 break; 58 default: 59 WARN_ON(1); 60 } 61 } 62 } 63 64 void ieee80211_link_stop(struct ieee80211_link_data *link) 65 { 66 if (link->sdata->vif.type == NL80211_IFTYPE_STATION) 67 ieee80211_mgd_stop_link(link); 68 69 ieee80211_link_release_channel(link); 70 } 71 72 struct link_container { 73 struct ieee80211_link_data data; 74 struct ieee80211_bss_conf conf; 75 }; 76 77 static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata, 78 struct link_container **links, u16 mask) 79 { 80 struct ieee80211_link_data *link; 81 LIST_HEAD(keys); 82 unsigned int link_id; 83 84 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 85 if (!(mask & BIT(link_id))) 86 continue; 87 link = &links[link_id]->data; 88 if (link_id == 0 && !link) 89 link = &sdata->deflink; 90 if (WARN_ON(!link)) 91 continue; 92 ieee80211_remove_link_keys(link, &keys); 93 ieee80211_link_stop(link); 94 } 95 96 synchronize_rcu(); 97 98 ieee80211_free_key_list(sdata->local, &keys); 99 } 100 101 static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata, 102 struct link_container **links) 103 { 104 unsigned int link_id; 105 106 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) 107 kfree(links[link_id]); 108 } 109 110 static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata) 111 { 112 unsigned int i, j; 113 114 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) { 115 struct ieee80211_link_data *link1; 116 117 link1 = sdata_dereference(sdata->link[i], sdata); 118 if (!link1) 119 continue; 120 for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) { 121 struct ieee80211_link_data *link2; 122 123 link2 = sdata_dereference(sdata->link[j], sdata); 124 if (!link2) 125 continue; 126 127 if (ether_addr_equal(link1->conf->addr, 128 link2->conf->addr)) 129 return -EALREADY; 130 } 131 } 132 133 return 0; 134 } 135 136 static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata, 137 u16 links) 138 { 139 sdata->vif.valid_links = links; 140 141 if (!links) { 142 sdata->vif.active_links = 0; 143 return; 144 } 145 146 switch (sdata->vif.type) { 147 case NL80211_IFTYPE_AP: 148 /* in an AP all links are always active */ 149 sdata->vif.active_links = links; 150 break; 151 case NL80211_IFTYPE_STATION: 152 if (sdata->vif.active_links) 153 break; 154 WARN_ON(hweight16(links) > 1); 155 sdata->vif.active_links = links; 156 break; 157 default: 158 WARN_ON(1); 159 } 160 } 161 162 static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata, 163 struct link_container **to_free, 164 u16 new_links) 165 { 166 u16 old_links = sdata->vif.valid_links; 167 u16 old_active = sdata->vif.active_links; 168 unsigned long add = new_links & ~old_links; 169 unsigned long rem = old_links & ~new_links; 170 unsigned int link_id; 171 int ret; 172 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link; 173 struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS]; 174 struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS]; 175 bool use_deflink = old_links == 0; /* set for error case */ 176 177 sdata_assert_lock(sdata); 178 179 memset(to_free, 0, sizeof(links)); 180 181 if (old_links == new_links) 182 return 0; 183 184 /* if there were no old links, need to clear the pointers to deflink */ 185 if (!old_links) 186 rem |= BIT(0); 187 188 /* allocate new link structures first */ 189 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 190 link = kzalloc(sizeof(*link), GFP_KERNEL); 191 if (!link) { 192 ret = -ENOMEM; 193 goto free; 194 } 195 links[link_id] = link; 196 } 197 198 /* keep track of the old pointers for the driver */ 199 BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf)); 200 memcpy(old, sdata->vif.link_conf, sizeof(old)); 201 /* and for us in error cases */ 202 BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link)); 203 memcpy(old_data, sdata->link, sizeof(old_data)); 204 205 /* grab old links to free later */ 206 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 207 if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) { 208 /* 209 * we must have allocated the data through this path so 210 * we know we can free both at the same time 211 */ 212 to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]), 213 typeof(*links[link_id]), 214 data); 215 } 216 217 RCU_INIT_POINTER(sdata->link[link_id], NULL); 218 RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL); 219 } 220 221 /* link them into data structures */ 222 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 223 WARN_ON(!use_deflink && 224 rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink); 225 226 link = links[link_id]; 227 ieee80211_link_init(sdata, link_id, &link->data, &link->conf); 228 ieee80211_link_setup(&link->data); 229 } 230 231 if (new_links == 0) 232 ieee80211_link_init(sdata, -1, &sdata->deflink, 233 &sdata->vif.bss_conf); 234 235 ret = ieee80211_check_dup_link_addrs(sdata); 236 if (!ret) { 237 /* for keys we will not be able to undo this */ 238 ieee80211_tear_down_links(sdata, to_free, rem); 239 240 ieee80211_set_vif_links_bitmaps(sdata, new_links); 241 242 /* tell the driver */ 243 ret = drv_change_vif_links(sdata->local, sdata, 244 old_links & old_active, 245 new_links & sdata->vif.active_links, 246 old); 247 } 248 249 if (ret) { 250 /* restore config */ 251 memcpy(sdata->link, old_data, sizeof(old_data)); 252 memcpy(sdata->vif.link_conf, old, sizeof(old)); 253 ieee80211_set_vif_links_bitmaps(sdata, old_links); 254 /* and free (only) the newly allocated links */ 255 memset(to_free, 0, sizeof(links)); 256 goto free; 257 } 258 259 /* use deflink/bss_conf again if and only if there are no more links */ 260 use_deflink = new_links == 0; 261 262 goto deinit; 263 free: 264 /* if we failed during allocation, only free all */ 265 for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) { 266 kfree(links[link_id]); 267 links[link_id] = NULL; 268 } 269 deinit: 270 if (use_deflink) 271 ieee80211_link_init(sdata, -1, &sdata->deflink, 272 &sdata->vif.bss_conf); 273 return ret; 274 } 275 276 int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata, 277 u16 new_links) 278 { 279 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS]; 280 int ret; 281 282 ret = ieee80211_vif_update_links(sdata, links, new_links); 283 ieee80211_free_links(sdata, links); 284 285 return ret; 286 } 287 288 void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata) 289 { 290 struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS]; 291 292 /* 293 * The locking here is different because when we free links 294 * in the station case we need to be able to cancel_work_sync() 295 * something that also takes the lock. 296 */ 297 298 sdata_lock(sdata); 299 ieee80211_vif_update_links(sdata, links, 0); 300 sdata_unlock(sdata); 301 302 ieee80211_free_links(sdata, links); 303 } 304 305 static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata, 306 u16 active_links) 307 { 308 struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS]; 309 struct ieee80211_local *local = sdata->local; 310 u16 old_active = sdata->vif.active_links; 311 unsigned long rem = old_active & ~active_links; 312 unsigned long add = active_links & ~old_active; 313 struct sta_info *sta; 314 unsigned int link_id; 315 int ret, i; 316 317 if (!ieee80211_sdata_running(sdata)) 318 return -ENETDOWN; 319 320 if (sdata->vif.type != NL80211_IFTYPE_STATION) 321 return -EINVAL; 322 323 /* cannot activate links that don't exist */ 324 if (active_links & ~sdata->vif.valid_links) 325 return -EINVAL; 326 327 /* nothing to do */ 328 if (old_active == active_links) 329 return 0; 330 331 for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) 332 link_confs[i] = sdata_dereference(sdata->vif.link_conf[i], 333 sdata); 334 335 if (add) { 336 sdata->vif.active_links |= active_links; 337 ret = drv_change_vif_links(local, sdata, 338 old_active, 339 sdata->vif.active_links, 340 link_confs); 341 if (ret) { 342 sdata->vif.active_links = old_active; 343 return ret; 344 } 345 } 346 347 for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) { 348 struct ieee80211_link_data *link; 349 350 link = sdata_dereference(sdata->link[link_id], sdata); 351 352 /* FIXME: kill TDLS connections on the link */ 353 354 ieee80211_link_release_channel(link); 355 } 356 357 list_for_each_entry(sta, &local->sta_list, list) { 358 if (sdata != sta->sdata) 359 continue; 360 ret = drv_change_sta_links(local, sdata, &sta->sta, 361 old_active, 362 old_active | active_links); 363 WARN_ON_ONCE(ret); 364 } 365 366 ret = ieee80211_key_switch_links(sdata, rem, add); 367 WARN_ON_ONCE(ret); 368 369 list_for_each_entry(sta, &local->sta_list, list) { 370 if (sdata != sta->sdata) 371 continue; 372 ret = drv_change_sta_links(local, sdata, &sta->sta, 373 old_active | active_links, 374 active_links); 375 WARN_ON_ONCE(ret); 376 } 377 378 for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) { 379 struct ieee80211_link_data *link; 380 381 link = sdata_dereference(sdata->link[link_id], sdata); 382 383 ret = ieee80211_link_use_channel(link, &link->conf->chandef, 384 IEEE80211_CHANCTX_SHARED); 385 WARN_ON_ONCE(ret); 386 387 ieee80211_link_info_change_notify(sdata, link, 388 BSS_CHANGED_ERP_CTS_PROT | 389 BSS_CHANGED_ERP_PREAMBLE | 390 BSS_CHANGED_ERP_SLOT | 391 BSS_CHANGED_HT | 392 BSS_CHANGED_BASIC_RATES | 393 BSS_CHANGED_BSSID | 394 BSS_CHANGED_CQM | 395 BSS_CHANGED_QOS | 396 BSS_CHANGED_TXPOWER | 397 BSS_CHANGED_BANDWIDTH | 398 BSS_CHANGED_TWT | 399 BSS_CHANGED_HE_OBSS_PD | 400 BSS_CHANGED_HE_BSS_COLOR); 401 ieee80211_mgd_set_link_qos_params(link); 402 } 403 404 old_active = sdata->vif.active_links; 405 sdata->vif.active_links = active_links; 406 407 if (rem) { 408 ret = drv_change_vif_links(local, sdata, old_active, 409 active_links, link_confs); 410 WARN_ON_ONCE(ret); 411 } 412 413 return 0; 414 } 415 416 int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links) 417 { 418 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 419 struct ieee80211_local *local = sdata->local; 420 u16 old_active; 421 int ret; 422 423 sdata_lock(sdata); 424 mutex_lock(&local->sta_mtx); 425 mutex_lock(&local->mtx); 426 mutex_lock(&local->key_mtx); 427 old_active = sdata->vif.active_links; 428 if (old_active & active_links) { 429 /* 430 * if there's at least one link that stays active across 431 * the change then switch to it (to those) first, and 432 * then enable the additional links 433 */ 434 ret = _ieee80211_set_active_links(sdata, 435 old_active & active_links); 436 if (!ret) 437 ret = _ieee80211_set_active_links(sdata, active_links); 438 } else { 439 /* otherwise switch directly */ 440 ret = _ieee80211_set_active_links(sdata, active_links); 441 } 442 mutex_unlock(&local->key_mtx); 443 mutex_unlock(&local->mtx); 444 mutex_unlock(&local->sta_mtx); 445 sdata_unlock(sdata); 446 447 return ret; 448 } 449 EXPORT_SYMBOL_GPL(ieee80211_set_active_links); 450 451 void ieee80211_set_active_links_async(struct ieee80211_vif *vif, 452 u16 active_links) 453 { 454 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 455 456 if (!ieee80211_sdata_running(sdata)) 457 return; 458 459 if (sdata->vif.type != NL80211_IFTYPE_STATION) 460 return; 461 462 /* cannot activate links that don't exist */ 463 if (active_links & ~sdata->vif.valid_links) 464 return; 465 466 /* nothing to do */ 467 if (sdata->vif.active_links == active_links) 468 return; 469 470 sdata->desired_active_links = active_links; 471 schedule_work(&sdata->activate_links_work); 472 } 473 EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async); 474