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(work: &link->csa_finalize_work, |
41 | func: ieee80211_csa_finalize_work); |
42 | wiphy_work_init(work: &link->color_change_finalize_work, |
43 | func: ieee80211_color_change_finalize_work); |
44 | INIT_DELAYED_WORK(&link->color_collision_detect_work, |
45 | ieee80211_color_collision_detection_work); |
46 | INIT_LIST_HEAD(list: &link->assigned_chanctx_list); |
47 | INIT_LIST_HEAD(list: &link->reserved_chanctx_list); |
48 | wiphy_delayed_work_init(dwork: &link->dfs_cac_timer_work, |
49 | func: ieee80211_dfs_cac_timer_work); |
50 | |
51 | if (!deflink) { |
52 | switch (sdata->vif.type) { |
53 | case NL80211_IFTYPE_AP: |
54 | ether_addr_copy(dst: link_conf->addr, |
55 | src: 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(dwork: &link->color_collision_detect_work); |
76 | wiphy_work_cancel(wiphy: link->sdata->local->hw.wiphy, |
77 | work: &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: &keys); |
102 | ieee80211_link_debugfs_remove(link); |
103 | ieee80211_link_stop(link); |
104 | } |
105 | |
106 | synchronize_rcu(); |
107 | |
108 | ieee80211_free_key_list(local: sdata->local, keys: &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(objp: 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(addr1: link1->conf->addr, |
138 | addr2: 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(size: 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, mld_vif: 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: &link->data, link_conf: &link->conf); |
250 | ieee80211_link_setup(link: &link->data); |
251 | } |
252 | |
253 | if (new_links == 0) |
254 | ieee80211_link_init(sdata, link_id: -1, link: &sdata->deflink, |
255 | link_conf: &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, links: to_free, mask: rem); |
261 | |
262 | ieee80211_set_vif_links_bitmaps(sdata, valid_links: new_links, dormant_links); |
263 | |
264 | /* tell the driver */ |
265 | ret = drv_change_vif_links(local: sdata->local, sdata, |
266 | old_links: old_links & old_active, |
267 | new_links: new_links & sdata->vif.active_links, |
268 | old); |
269 | if (!new_links) |
270 | ieee80211_debugfs_recreate_netdev(sdata, mld_vif: 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, valid_links: 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(objp: links[link_id]); |
291 | links[link_id] = NULL; |
292 | } |
293 | deinit: |
294 | if (use_deflink) |
295 | ieee80211_link_init(sdata, link_id: -1, link: &sdata->deflink, |
296 | link_conf: &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, to_free: 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(vif: &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_links: old_active, |
346 | new_links: sdata->vif.active_links, |
347 | old: 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); |
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 | active_links: old_active | active_links); |
371 | |
372 | ret = drv_change_sta_links(local, sdata, sta: &sta->sta, |
373 | old_links: old_active, |
374 | new_links: old_active | active_links); |
375 | WARN_ON_ONCE(ret); |
376 | } |
377 | |
378 | ret = ieee80211_key_switch_links(sdata, del_links_mask: rem, add_links_mask: 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->sta, |
388 | old_links: old_active | active_links, |
389 | new_links: 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 | ret = ieee80211_link_use_channel(link, |
408 | req: &link->conf->chanreq, |
409 | mode: IEEE80211_CHANCTX_SHARED); |
410 | WARN_ON_ONCE(ret); |
411 | |
412 | ieee80211_mgd_set_link_qos_params(link); |
413 | ieee80211_link_info_change_notify(sdata, link, |
414 | changed: BSS_CHANGED_ERP_CTS_PROT | |
415 | BSS_CHANGED_ERP_PREAMBLE | |
416 | BSS_CHANGED_ERP_SLOT | |
417 | BSS_CHANGED_HT | |
418 | BSS_CHANGED_BASIC_RATES | |
419 | BSS_CHANGED_BSSID | |
420 | BSS_CHANGED_CQM | |
421 | BSS_CHANGED_QOS | |
422 | BSS_CHANGED_TXPOWER | |
423 | BSS_CHANGED_BANDWIDTH | |
424 | BSS_CHANGED_TWT | |
425 | BSS_CHANGED_HE_OBSS_PD | |
426 | BSS_CHANGED_HE_BSS_COLOR); |
427 | } |
428 | |
429 | old_active = sdata->vif.active_links; |
430 | sdata->vif.active_links = active_links; |
431 | |
432 | if (rem) { |
433 | ret = drv_change_vif_links(local, sdata, old_links: old_active, |
434 | new_links: active_links, old: link_confs); |
435 | WARN_ON_ONCE(ret); |
436 | } |
437 | |
438 | return 0; |
439 | } |
440 | |
441 | int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links) |
442 | { |
443 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(p: vif); |
444 | struct ieee80211_local *local = sdata->local; |
445 | u16 old_active; |
446 | int ret; |
447 | |
448 | lockdep_assert_wiphy(local->hw.wiphy); |
449 | |
450 | if (WARN_ON(!active_links)) |
451 | return -EINVAL; |
452 | |
453 | if (!drv_can_activate_links(local, sdata, active_links)) |
454 | return -EINVAL; |
455 | |
456 | old_active = sdata->vif.active_links; |
457 | if (old_active & active_links) { |
458 | /* |
459 | * if there's at least one link that stays active across |
460 | * the change then switch to it (to those) first, and |
461 | * then enable the additional links |
462 | */ |
463 | ret = _ieee80211_set_active_links(sdata, |
464 | active_links: old_active & active_links); |
465 | if (!ret) |
466 | ret = _ieee80211_set_active_links(sdata, active_links); |
467 | } else { |
468 | /* otherwise switch directly */ |
469 | ret = _ieee80211_set_active_links(sdata, active_links); |
470 | } |
471 | |
472 | return ret; |
473 | } |
474 | EXPORT_SYMBOL_GPL(ieee80211_set_active_links); |
475 | |
476 | void ieee80211_set_active_links_async(struct ieee80211_vif *vif, |
477 | u16 active_links) |
478 | { |
479 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(p: vif); |
480 | |
481 | if (WARN_ON(!active_links)) |
482 | return; |
483 | |
484 | if (!ieee80211_sdata_running(sdata)) |
485 | return; |
486 | |
487 | if (sdata->vif.type != NL80211_IFTYPE_STATION) |
488 | return; |
489 | |
490 | if (active_links & ~ieee80211_vif_usable_links(vif: &sdata->vif)) |
491 | return; |
492 | |
493 | /* nothing to do */ |
494 | if (sdata->vif.active_links == active_links) |
495 | return; |
496 | |
497 | sdata->desired_active_links = active_links; |
498 | wiphy_work_queue(wiphy: sdata->local->hw.wiphy, work: &sdata->activate_links_work); |
499 | } |
500 | EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async); |
501 | |