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);
109 * recalc the min required chan width of the channel context, which is
110 * the max of min required widths of all the interfaces bound to this
113 void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
114 struct ieee80211_chanctx *ctx)
116 enum nl80211_chan_width max_bw;
117 struct cfg80211_chan_def min_def;
119 lockdep_assert_held(&local->chanctx_mtx);
121 /* don't optimize 5MHz, 10MHz, and radar_enabled confs */
122 if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
123 ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
124 ctx->conf.radar_enabled) {
125 ctx->conf.min_def = ctx->conf.def;
129 max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);
131 /* downgrade chandef up to max_bw */
132 min_def = ctx->conf.def;
133 while (min_def.width > max_bw)
134 ieee80211_chandef_downgrade(&min_def);
136 if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
139 ctx->conf.min_def = min_def;
140 if (!ctx->driver_present)
143 drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
146 static void ieee80211_change_chanctx(struct ieee80211_local *local,
147 struct ieee80211_chanctx *ctx,
148 const struct cfg80211_chan_def *chandef)
150 if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
153 WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
155 ctx->conf.def = *chandef;
156 drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
157 ieee80211_recalc_chanctx_min_def(local, ctx);
159 if (!local->use_chanctx) {
160 local->_oper_chandef = *chandef;
161 ieee80211_hw_config(local, 0);
165 static struct ieee80211_chanctx *
166 ieee80211_find_chanctx(struct ieee80211_local *local,
167 const struct cfg80211_chan_def *chandef,
168 enum ieee80211_chanctx_mode mode)
170 struct ieee80211_chanctx *ctx;
172 lockdep_assert_held(&local->chanctx_mtx);
174 if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
177 list_for_each_entry(ctx, &local->chanctx_list, list) {
178 const struct cfg80211_chan_def *compat;
180 if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
183 compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
187 ieee80211_change_chanctx(local, ctx, compat);
195 static bool ieee80211_is_radar_required(struct ieee80211_local *local)
197 struct ieee80211_sub_if_data *sdata;
200 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
201 if (sdata->radar_required) {
211 static struct ieee80211_chanctx *
212 ieee80211_new_chanctx(struct ieee80211_local *local,
213 const struct cfg80211_chan_def *chandef,
214 enum ieee80211_chanctx_mode mode)
216 struct ieee80211_chanctx *ctx;
220 lockdep_assert_held(&local->chanctx_mtx);
222 ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
224 return ERR_PTR(-ENOMEM);
226 ctx->conf.def = *chandef;
227 ctx->conf.rx_chains_static = 1;
228 ctx->conf.rx_chains_dynamic = 1;
230 ctx->conf.radar_enabled = ieee80211_is_radar_required(local);
231 ieee80211_recalc_chanctx_min_def(local, ctx);
232 if (!local->use_chanctx)
233 local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
235 /* acquire mutex to prevent idle from changing */
236 mutex_lock(&local->mtx);
237 /* turn idle off *before* setting channel -- some drivers need that */
238 changed = ieee80211_idle_off(local);
240 ieee80211_hw_config(local, changed);
242 if (!local->use_chanctx) {
243 local->_oper_chandef = *chandef;
244 ieee80211_hw_config(local, 0);
246 err = drv_add_chanctx(local, ctx);
251 ieee80211_recalc_idle(local);
256 /* and keep the mutex held until the new chanctx is on the list */
257 list_add_rcu(&ctx->list, &local->chanctx_list);
260 mutex_unlock(&local->mtx);
265 static void ieee80211_free_chanctx(struct ieee80211_local *local,
266 struct ieee80211_chanctx *ctx)
268 bool check_single_channel = false;
269 lockdep_assert_held(&local->chanctx_mtx);
271 WARN_ON_ONCE(ctx->refcount != 0);
273 if (!local->use_chanctx) {
274 struct cfg80211_chan_def *chandef = &local->_oper_chandef;
275 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
276 chandef->center_freq1 = chandef->chan->center_freq;
277 chandef->center_freq2 = 0;
279 /* NOTE: Disabling radar is only valid here for
280 * single channel context. To be sure, check it ...
282 if (local->hw.conf.radar_enabled)
283 check_single_channel = true;
284 local->hw.conf.radar_enabled = false;
286 ieee80211_hw_config(local, 0);
288 drv_remove_chanctx(local, ctx);
291 list_del_rcu(&ctx->list);
292 kfree_rcu(ctx, rcu_head);
294 /* throw a warning if this wasn't the only channel context. */
295 WARN_ON(check_single_channel && !list_empty(&local->chanctx_list));
297 mutex_lock(&local->mtx);
298 ieee80211_recalc_idle(local);
299 mutex_unlock(&local->mtx);
302 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
303 struct ieee80211_chanctx *ctx)
305 struct ieee80211_local *local = sdata->local;
308 lockdep_assert_held(&local->chanctx_mtx);
310 ret = drv_assign_vif_chanctx(local, sdata, ctx);
314 rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
317 ieee80211_recalc_txpower(sdata);
318 ieee80211_recalc_chanctx_min_def(local, ctx);
319 sdata->vif.bss_conf.idle = false;
321 if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
322 sdata->vif.type != NL80211_IFTYPE_MONITOR)
323 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
328 static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
329 struct ieee80211_chanctx *ctx)
331 struct ieee80211_chanctx_conf *conf = &ctx->conf;
332 struct ieee80211_sub_if_data *sdata;
333 const struct cfg80211_chan_def *compat = NULL;
335 lockdep_assert_held(&local->chanctx_mtx);
338 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
340 if (!ieee80211_sdata_running(sdata))
342 if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
346 compat = &sdata->vif.bss_conf.chandef;
348 compat = cfg80211_chandef_compatible(
349 &sdata->vif.bss_conf.chandef, compat);
355 if (WARN_ON_ONCE(!compat))
358 ieee80211_change_chanctx(local, ctx, compat);
361 static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
362 struct ieee80211_chanctx *ctx)
364 struct ieee80211_local *local = sdata->local;
366 lockdep_assert_held(&local->chanctx_mtx);
369 rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
371 sdata->vif.bss_conf.idle = true;
373 if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
374 sdata->vif.type != NL80211_IFTYPE_MONITOR)
375 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
377 drv_unassign_vif_chanctx(local, sdata, ctx);
379 if (ctx->refcount > 0) {
380 ieee80211_recalc_chanctx_chantype(sdata->local, ctx);
381 ieee80211_recalc_smps_chanctx(local, ctx);
382 ieee80211_recalc_radar_chanctx(local, ctx);
383 ieee80211_recalc_chanctx_min_def(local, ctx);
387 static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
389 struct ieee80211_local *local = sdata->local;
390 struct ieee80211_chanctx_conf *conf;
391 struct ieee80211_chanctx *ctx;
393 lockdep_assert_held(&local->chanctx_mtx);
395 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
396 lockdep_is_held(&local->chanctx_mtx));
400 ctx = container_of(conf, struct ieee80211_chanctx, conf);
402 ieee80211_unassign_vif_chanctx(sdata, ctx);
403 if (ctx->refcount == 0)
404 ieee80211_free_chanctx(local, ctx);
407 void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
408 struct ieee80211_chanctx *chanctx)
412 lockdep_assert_held(&local->chanctx_mtx);
414 radar_enabled = ieee80211_is_radar_required(local);
416 if (radar_enabled == chanctx->conf.radar_enabled)
419 chanctx->conf.radar_enabled = radar_enabled;
420 local->radar_detect_enabled = chanctx->conf.radar_enabled;
422 if (!local->use_chanctx) {
423 local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
424 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
427 drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
430 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
431 struct ieee80211_chanctx *chanctx)
433 struct ieee80211_sub_if_data *sdata;
434 u8 rx_chains_static, rx_chains_dynamic;
436 lockdep_assert_held(&local->chanctx_mtx);
438 rx_chains_static = 1;
439 rx_chains_dynamic = 1;
442 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
443 u8 needed_static, needed_dynamic;
445 if (!ieee80211_sdata_running(sdata))
448 if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
452 switch (sdata->vif.type) {
453 case NL80211_IFTYPE_P2P_DEVICE:
455 case NL80211_IFTYPE_STATION:
456 if (!sdata->u.mgd.associated)
459 case NL80211_IFTYPE_AP_VLAN:
461 case NL80211_IFTYPE_AP:
462 case NL80211_IFTYPE_ADHOC:
463 case NL80211_IFTYPE_WDS:
464 case NL80211_IFTYPE_MESH_POINT:
470 switch (sdata->smps_mode) {
472 WARN_ONCE(1, "Invalid SMPS mode %d\n",
475 case IEEE80211_SMPS_OFF:
476 needed_static = sdata->needed_rx_chains;
477 needed_dynamic = sdata->needed_rx_chains;
479 case IEEE80211_SMPS_DYNAMIC:
481 needed_dynamic = sdata->needed_rx_chains;
483 case IEEE80211_SMPS_STATIC:
489 rx_chains_static = max(rx_chains_static, needed_static);
490 rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
494 if (!local->use_chanctx) {
495 if (rx_chains_static > 1)
496 local->smps_mode = IEEE80211_SMPS_OFF;
497 else if (rx_chains_dynamic > 1)
498 local->smps_mode = IEEE80211_SMPS_DYNAMIC;
500 local->smps_mode = IEEE80211_SMPS_STATIC;
501 ieee80211_hw_config(local, 0);
504 if (rx_chains_static == chanctx->conf.rx_chains_static &&
505 rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
508 chanctx->conf.rx_chains_static = rx_chains_static;
509 chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
510 drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
513 int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
514 const struct cfg80211_chan_def *chandef,
515 enum ieee80211_chanctx_mode mode)
517 struct ieee80211_local *local = sdata->local;
518 struct ieee80211_chanctx *ctx;
521 WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
523 mutex_lock(&local->chanctx_mtx);
524 __ieee80211_vif_release_channel(sdata);
526 ctx = ieee80211_find_chanctx(local, chandef, mode);
528 ctx = ieee80211_new_chanctx(local, chandef, mode);
534 sdata->vif.bss_conf.chandef = *chandef;
536 ret = ieee80211_assign_vif_chanctx(sdata, ctx);
538 /* if assign fails refcount stays the same */
539 if (ctx->refcount == 0)
540 ieee80211_free_chanctx(local, ctx);
544 ieee80211_recalc_smps_chanctx(local, ctx);
545 ieee80211_recalc_radar_chanctx(local, ctx);
547 mutex_unlock(&local->chanctx_mtx);
551 int ieee80211_vif_change_channel(struct ieee80211_sub_if_data *sdata,
554 struct ieee80211_local *local = sdata->local;
555 struct ieee80211_chanctx_conf *conf;
556 struct ieee80211_chanctx *ctx;
557 const struct cfg80211_chan_def *chandef = &sdata->csa_chandef;
559 u32 chanctx_changed = 0;
561 /* should never be called if not performing a channel switch. */
562 if (WARN_ON(!sdata->vif.csa_active))
565 if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
566 IEEE80211_CHAN_DISABLED))
569 mutex_lock(&local->chanctx_mtx);
570 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
571 lockdep_is_held(&local->chanctx_mtx));
577 ctx = container_of(conf, struct ieee80211_chanctx, conf);
578 if (ctx->refcount != 1) {
583 if (sdata->vif.bss_conf.chandef.width != chandef->width) {
584 chanctx_changed = IEEE80211_CHANCTX_CHANGE_WIDTH;
585 *changed |= BSS_CHANGED_BANDWIDTH;
588 sdata->vif.bss_conf.chandef = *chandef;
589 ctx->conf.def = *chandef;
591 chanctx_changed |= IEEE80211_CHANCTX_CHANGE_CHANNEL;
592 drv_change_chanctx(local, ctx, chanctx_changed);
594 ieee80211_recalc_chanctx_chantype(local, ctx);
595 ieee80211_recalc_smps_chanctx(local, ctx);
596 ieee80211_recalc_radar_chanctx(local, ctx);
597 ieee80211_recalc_chanctx_min_def(local, ctx);
601 mutex_unlock(&local->chanctx_mtx);
605 int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
606 const struct cfg80211_chan_def *chandef,
609 struct ieee80211_local *local = sdata->local;
610 struct ieee80211_chanctx_conf *conf;
611 struct ieee80211_chanctx *ctx;
614 if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
615 IEEE80211_CHAN_DISABLED))
618 mutex_lock(&local->chanctx_mtx);
619 if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
624 if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
625 sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
630 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
631 lockdep_is_held(&local->chanctx_mtx));
637 ctx = container_of(conf, struct ieee80211_chanctx, conf);
638 if (!cfg80211_chandef_compatible(&conf->def, chandef)) {
643 sdata->vif.bss_conf.chandef = *chandef;
645 ieee80211_recalc_chanctx_chantype(local, ctx);
647 *changed |= BSS_CHANGED_BANDWIDTH;
650 mutex_unlock(&local->chanctx_mtx);
654 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
656 WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
658 mutex_lock(&sdata->local->chanctx_mtx);
659 __ieee80211_vif_release_channel(sdata);
660 mutex_unlock(&sdata->local->chanctx_mtx);
663 void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
665 struct ieee80211_local *local = sdata->local;
666 struct ieee80211_sub_if_data *ap;
667 struct ieee80211_chanctx_conf *conf;
669 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
672 ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
674 mutex_lock(&local->chanctx_mtx);
676 conf = rcu_dereference_protected(ap->vif.chanctx_conf,
677 lockdep_is_held(&local->chanctx_mtx));
678 rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
679 mutex_unlock(&local->chanctx_mtx);
682 void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
685 struct ieee80211_local *local = sdata->local;
686 struct ieee80211_sub_if_data *vlan;
687 struct ieee80211_chanctx_conf *conf;
691 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
694 mutex_lock(&local->chanctx_mtx);
697 * Check that conf exists, even when clearing this function
698 * must be called with the AP's channel context still there
699 * as it would otherwise cause VLANs to have an invalid
700 * channel context pointer for a while, possibly pointing
701 * to a channel context that has already been freed.
703 conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
704 lockdep_is_held(&local->chanctx_mtx));
710 list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
711 rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
713 mutex_unlock(&local->chanctx_mtx);
716 void ieee80211_iter_chan_contexts_atomic(
717 struct ieee80211_hw *hw,
718 void (*iter)(struct ieee80211_hw *hw,
719 struct ieee80211_chanctx_conf *chanctx_conf,
723 struct ieee80211_local *local = hw_to_local(hw);
724 struct ieee80211_chanctx *ctx;
727 list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
728 if (ctx->driver_present)
729 iter(hw, &ctx->conf, iter_data);
732 EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);