2 * mac80211 - channel management
5 #include <linux/nl80211.h>
6 #include <linux/export.h>
7 #include <linux/rtnetlink.h>
8 #include <net/cfg80211.h>
9 #include "ieee80211_i.h"
10 #include "driver-ops.h"
12 static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
14 switch (sta->bandwidth) {
15 case IEEE80211_STA_RX_BW_20:
16 if (sta->ht_cap.ht_supported)
17 return NL80211_CHAN_WIDTH_20;
19 return NL80211_CHAN_WIDTH_20_NOHT;
20 case IEEE80211_STA_RX_BW_40:
21 return NL80211_CHAN_WIDTH_40;
22 case IEEE80211_STA_RX_BW_80:
23 return NL80211_CHAN_WIDTH_80;
24 case IEEE80211_STA_RX_BW_160:
26 * This applied for both 160 and 80+80. since we use
27 * the returned value to consider degradation of
28 * ctx->conf.min_def, we have to make sure to take
29 * the bigger one (NL80211_CHAN_WIDTH_160).
30 * Otherwise we might try degrading even when not
31 * needed, as the max required sta_bw returned (80+80)
32 * might be smaller than the configured bw (160).
34 return NL80211_CHAN_WIDTH_160;
37 return NL80211_CHAN_WIDTH_20;
41 static enum nl80211_chan_width
42 ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
44 enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
48 list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
49 if (sdata != sta->sdata &&
50 !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
56 max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
63 static enum nl80211_chan_width
64 ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
65 struct ieee80211_chanctx_conf *conf)
67 struct ieee80211_sub_if_data *sdata;
68 enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
71 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
72 struct ieee80211_vif *vif = &sdata->vif;
73 enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;
75 if (!ieee80211_sdata_running(sdata))
78 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
82 case NL80211_IFTYPE_AP:
83 case NL80211_IFTYPE_AP_VLAN:
84 width = ieee80211_get_max_required_bw(sdata);
86 case NL80211_IFTYPE_P2P_DEVICE:
88 case NL80211_IFTYPE_STATION:
89 case NL80211_IFTYPE_ADHOC:
90 case NL80211_IFTYPE_WDS:
91 case NL80211_IFTYPE_MESH_POINT:
92 width = vif->bss_conf.chandef.width;
94 case NL80211_IFTYPE_UNSPECIFIED:
95 case NUM_NL80211_IFTYPES:
96 case NL80211_IFTYPE_MONITOR:
97 case NL80211_IFTYPE_P2P_CLIENT:
98 case NL80211_IFTYPE_P2P_GO:
101 max_bw = max(max_bw, width);
104 /* use the configured bandwidth in case of monitor interface */
105 sdata = rcu_dereference(local->monitor_sdata);
106 if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
107 max_bw = max(max_bw, conf->def.width);
115 * recalc the min required chan width of the channel context, which is
116 * the max of min required widths of all the interfaces bound to this
119 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
120 struct ieee80211_chanctx *ctx)
122 enum nl80211_chan_width max_bw;
123 struct cfg80211_chan_def min_def;
125 lockdep_assert_held(&local->chanctx_mtx);
127 /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
128 if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
129 ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
130 ctx->conf.radar_enabled) {
131 ctx->conf.min_def = ctx->conf.def;
135 max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
137 /* downgrade chandef up to max_bw */
138 min_def = ctx->conf.def;
139 while (min_def.width > max_bw)
140 ieee80211_chandef_downgrade(&min_def);
142 if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
145 ctx->conf.min_def = min_def;
146 if (!ctx->driver_present)
149 drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
152 static void ieee80211_change_chanctx(struct ieee80211_local *local,
153 struct ieee80211_chanctx *ctx,
154 const struct cfg80211_chan_def *chandef)
156 if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
159 WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
161 ctx->conf.def = *chandef;
162 drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
163 ieee80211_recalc_chanctx_min_def(local, ctx);
165 if (!local->use_chanctx) {
166 local->_oper_chandef = *chandef;
167 ieee80211_hw_config(local, 0);
171 static struct ieee80211_chanctx *
172 ieee80211_find_chanctx(struct ieee80211_local *local,
173 const struct cfg80211_chan_def *chandef,
174 enum ieee80211_chanctx_mode mode)
176 struct ieee80211_chanctx *ctx;
178 lockdep_assert_held(&local->chanctx_mtx);
180 if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
183 list_for_each_entry(ctx, &local->chanctx_list, list) {
184 const struct cfg80211_chan_def *compat;
186 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
189 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
193 ieee80211_change_chanctx(local, ctx, compat);
201 static bool ieee80211_is_radar_required(struct ieee80211_local *local)
203 struct ieee80211_sub_if_data *sdata;
206 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
207 if (sdata->radar_required) {
217 static struct ieee80211_chanctx *
218 ieee80211_new_chanctx(struct ieee80211_local *local,
219 const struct cfg80211_chan_def *chandef,
220 enum ieee80211_chanctx_mode mode)
222 struct ieee80211_chanctx *ctx;
226 lockdep_assert_held(&local->chanctx_mtx);
228 ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
230 return ERR_PTR(-ENOMEM);
232 ctx->conf.def = *chandef;
233 ctx->conf.rx_chains_static = 1;
234 ctx->conf.rx_chains_dynamic = 1;
236 ctx->conf.radar_enabled = ieee80211_is_radar_required(local);
237 ieee80211_recalc_chanctx_min_def(local, ctx);
238 if (!local->use_chanctx)
239 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
241 /* we hold the mutex to prevent idle from changing */
242 lockdep_assert_held(&local->mtx);
243 /* turn idle off *before* setting channel -- some drivers need that */
244 changed = ieee80211_idle_off(local);
246 ieee80211_hw_config(local, changed);
248 if (!local->use_chanctx) {
249 local->_oper_chandef = *chandef;
250 ieee80211_hw_config(local, 0);
252 err = drv_add_chanctx(local, ctx);
255 ieee80211_recalc_idle(local);
260 /* and keep the mutex held until the new chanctx is on the list */
261 list_add_rcu(&ctx->list, &local->chanctx_list);
266 static void ieee80211_free_chanctx(struct ieee80211_local *local,
267 struct ieee80211_chanctx *ctx)
269 bool check_single_channel = false;
270 lockdep_assert_held(&local->chanctx_mtx);
272 WARN_ON_ONCE(ctx->refcount != 0);
274 if (!local->use_chanctx) {
275 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
276 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
277 chandef->center_freq1 = chandef->chan->center_freq;
278 chandef->center_freq2 = 0;
280 /* NOTE: Disabling radar is only valid here for
281 * single channel context. To be sure, check it ...
283 if (local->hw.conf.radar_enabled)
284 check_single_channel = true;
285 local->hw.conf.radar_enabled = false;
287 ieee80211_hw_config(local, 0);
289 drv_remove_chanctx(local, ctx);
292 list_del_rcu(&ctx->list);
293 kfree_rcu(ctx, rcu_head);
295 /* throw a warning if this wasn't the only channel context. */
296 WARN_ON(check_single_channel && !list_empty(&local->chanctx_list));
298 ieee80211_recalc_idle(local);
301 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
302 struct ieee80211_chanctx *ctx)
304 struct ieee80211_local *local = sdata->local;
307 lockdep_assert_held(&local->chanctx_mtx);
309 ret = drv_assign_vif_chanctx(local, sdata, ctx);
313 rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
316 ieee80211_recalc_txpower(sdata);
317 ieee80211_recalc_chanctx_min_def(local, ctx);
318 sdata->vif.bss_conf.idle = false;
320 if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
321 sdata->vif.type != NL80211_IFTYPE_MONITOR)
322 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
327 static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
328 struct ieee80211_chanctx *ctx)
330 struct ieee80211_chanctx_conf *conf = &ctx->conf;
331 struct ieee80211_sub_if_data *sdata;
332 const struct cfg80211_chan_def *compat = NULL;
334 lockdep_assert_held(&local->chanctx_mtx);
337 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
339 if (!ieee80211_sdata_running(sdata))
341 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
345 compat = &sdata->vif.bss_conf.chandef;
347 compat = cfg80211_chandef_compatible(
348 &sdata->vif.bss_conf.chandef, compat);
354 if (WARN_ON_ONCE(!compat))
357 ieee80211_change_chanctx(local, ctx, compat);
360 static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
361 struct ieee80211_chanctx *chanctx)
365 lockdep_assert_held(&local->chanctx_mtx);
366 /* for setting local->radar_detect_enabled */
367 lockdep_assert_held(&local->mtx);
369 radar_enabled = ieee80211_is_radar_required(local);
371 if (radar_enabled == chanctx->conf.radar_enabled)
374 chanctx->conf.radar_enabled = radar_enabled;
375 local->radar_detect_enabled = chanctx->conf.radar_enabled;
377 if (!local->use_chanctx) {
378 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
379 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
382 drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
385 static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
386 struct ieee80211_chanctx *ctx)
388 struct ieee80211_local *local = sdata->local;
390 lockdep_assert_held(&local->chanctx_mtx);
393 rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
395 sdata->vif.bss_conf.idle = true;
397 if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
398 sdata->vif.type != NL80211_IFTYPE_MONITOR)
399 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
401 drv_unassign_vif_chanctx(local, sdata, ctx);
403 if (ctx->refcount > 0) {
404 ieee80211_recalc_chanctx_chantype(sdata->local, ctx);
405 ieee80211_recalc_smps_chanctx(local, ctx);
406 ieee80211_recalc_radar_chanctx(local, ctx);
407 ieee80211_recalc_chanctx_min_def(local, ctx);
411 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
413 struct ieee80211_local *local = sdata->local;
414 struct ieee80211_chanctx_conf *conf;
415 struct ieee80211_chanctx *ctx;
417 lockdep_assert_held(&local->chanctx_mtx);
419 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
420 lockdep_is_held(&local->chanctx_mtx));
424 ctx = container_of(conf, struct ieee80211_chanctx, conf);
426 ieee80211_unassign_vif_chanctx(sdata, ctx);
427 if (ctx->refcount == 0)
428 ieee80211_free_chanctx(local, ctx);
431 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
432 struct ieee80211_chanctx *chanctx)
434 struct ieee80211_sub_if_data *sdata;
435 u8 rx_chains_static, rx_chains_dynamic;
437 lockdep_assert_held(&local->chanctx_mtx);
439 rx_chains_static = 1;
440 rx_chains_dynamic = 1;
443 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
444 u8 needed_static, needed_dynamic;
446 if (!ieee80211_sdata_running(sdata))
449 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
453 switch (sdata->vif.type) {
454 case NL80211_IFTYPE_P2P_DEVICE:
456 case NL80211_IFTYPE_STATION:
457 if (!sdata->u.mgd.associated)
460 case NL80211_IFTYPE_AP_VLAN:
462 case NL80211_IFTYPE_AP:
463 case NL80211_IFTYPE_ADHOC:
464 case NL80211_IFTYPE_WDS:
465 case NL80211_IFTYPE_MESH_POINT:
471 switch (sdata->smps_mode) {
473 WARN_ONCE(1, "Invalid SMPS mode %d\n",
476 case IEEE80211_SMPS_OFF:
477 needed_static = sdata->needed_rx_chains;
478 needed_dynamic = sdata->needed_rx_chains;
480 case IEEE80211_SMPS_DYNAMIC:
482 needed_dynamic = sdata->needed_rx_chains;
484 case IEEE80211_SMPS_STATIC:
490 rx_chains_static = max(rx_chains_static, needed_static);
491 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
495 if (!local->use_chanctx) {
496 if (rx_chains_static > 1)
497 local->smps_mode = IEEE80211_SMPS_OFF;
498 else if (rx_chains_dynamic > 1)
499 local->smps_mode = IEEE80211_SMPS_DYNAMIC;
501 local->smps_mode = IEEE80211_SMPS_STATIC;
502 ieee80211_hw_config(local, 0);
505 if (rx_chains_static == chanctx->conf.rx_chains_static &&
506 rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
509 chanctx->conf.rx_chains_static = rx_chains_static;
510 chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
511 drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
514 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
515 const struct cfg80211_chan_def *chandef,
516 enum ieee80211_chanctx_mode mode)
518 struct ieee80211_local *local = sdata->local;
519 struct ieee80211_chanctx *ctx;
522 lockdep_assert_held(&local->mtx);
524 WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
526 mutex_lock(&local->chanctx_mtx);
527 __ieee80211_vif_release_channel(sdata);
529 ctx = ieee80211_find_chanctx(local, chandef, mode);
531 ctx = ieee80211_new_chanctx(local, chandef, mode);
537 sdata->vif.bss_conf.chandef = *chandef;
539 ret = ieee80211_assign_vif_chanctx(sdata, ctx);
541 /* if assign fails refcount stays the same */
542 if (ctx->refcount == 0)
543 ieee80211_free_chanctx(local, ctx);
547 ieee80211_recalc_smps_chanctx(local, ctx);
548 ieee80211_recalc_radar_chanctx(local, ctx);
550 mutex_unlock(&local->chanctx_mtx);
554 int ieee80211_vif_change_channel(struct ieee80211_sub_if_data *sdata,
557 struct ieee80211_local *local = sdata->local;
558 struct ieee80211_chanctx_conf *conf;
559 struct ieee80211_chanctx *ctx;
560 const struct cfg80211_chan_def *chandef = &sdata->csa_chandef;
562 u32 chanctx_changed = 0;
564 lockdep_assert_held(&local->mtx);
566 /* should never be called if not performing a channel switch. */
567 if (WARN_ON(!sdata->vif.csa_active))
570 if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
571 IEEE80211_CHAN_DISABLED))
574 mutex_lock(&local->chanctx_mtx);
575 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
576 lockdep_is_held(&local->chanctx_mtx));
582 ctx = container_of(conf, struct ieee80211_chanctx, conf);
583 if (ctx->refcount != 1) {
588 if (sdata->vif.bss_conf.chandef.width != chandef->width) {
589 chanctx_changed = IEEE80211_CHANCTX_CHANGE_WIDTH;
590 *changed |= BSS_CHANGED_BANDWIDTH;
593 sdata->vif.bss_conf.chandef = *chandef;
594 ctx->conf.def = *chandef;
596 chanctx_changed |= IEEE80211_CHANCTX_CHANGE_CHANNEL;
597 drv_change_chanctx(local, ctx, chanctx_changed);
599 ieee80211_recalc_chanctx_chantype(local, ctx);
600 ieee80211_recalc_smps_chanctx(local, ctx);
601 ieee80211_recalc_radar_chanctx(local, ctx);
602 ieee80211_recalc_chanctx_min_def(local, ctx);
606 mutex_unlock(&local->chanctx_mtx);
610 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
611 const struct cfg80211_chan_def *chandef,
614 struct ieee80211_local *local = sdata->local;
615 struct ieee80211_chanctx_conf *conf;
616 struct ieee80211_chanctx *ctx;
619 if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
620 IEEE80211_CHAN_DISABLED))
623 mutex_lock(&local->chanctx_mtx);
624 if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
629 if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
630 sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
635 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
636 lockdep_is_held(&local->chanctx_mtx));
642 ctx = container_of(conf, struct ieee80211_chanctx, conf);
643 if (!cfg80211_chandef_compatible(&conf->def, chandef)) {
648 sdata->vif.bss_conf.chandef = *chandef;
650 ieee80211_recalc_chanctx_chantype(local, ctx);
652 *changed |= BSS_CHANGED_BANDWIDTH;
655 mutex_unlock(&local->chanctx_mtx);
659 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
661 WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
663 lockdep_assert_held(&sdata->local->mtx);
665 mutex_lock(&sdata->local->chanctx_mtx);
666 __ieee80211_vif_release_channel(sdata);
667 mutex_unlock(&sdata->local->chanctx_mtx);
670 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
672 struct ieee80211_local *local = sdata->local;
673 struct ieee80211_sub_if_data *ap;
674 struct ieee80211_chanctx_conf *conf;
676 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
679 ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
681 mutex_lock(&local->chanctx_mtx);
683 conf = rcu_dereference_protected(ap->vif.chanctx_conf,
684 lockdep_is_held(&local->chanctx_mtx));
685 rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
686 mutex_unlock(&local->chanctx_mtx);
689 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
692 struct ieee80211_local *local = sdata->local;
693 struct ieee80211_sub_if_data *vlan;
694 struct ieee80211_chanctx_conf *conf;
698 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
701 mutex_lock(&local->chanctx_mtx);
704 * Check that conf exists, even when clearing this function
705 * must be called with the AP's channel context still there
706 * as it would otherwise cause VLANs to have an invalid
707 * channel context pointer for a while, possibly pointing
708 * to a channel context that has already been freed.
710 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
711 lockdep_is_held(&local->chanctx_mtx));
717 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
718 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
720 mutex_unlock(&local->chanctx_mtx);
723 void ieee80211_iter_chan_contexts_atomic(
724 struct ieee80211_hw *hw,
725 void (*iter)(struct ieee80211_hw *hw,
726 struct ieee80211_chanctx_conf *chanctx_conf,
730 struct ieee80211_local *local = hw_to_local(hw);
731 struct ieee80211_chanctx *ctx;
734 list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
735 if (ctx->driver_present)
736 iter(hw, &ctx->conf, iter_data);
739 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);