chan.c 42.5 KB
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/*
 * mac80211 - channel management
 */

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#include <linux/nl80211.h>
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#include <linux/export.h>
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#include <linux/rtnetlink.h>
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#include <net/cfg80211.h>
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#include "ieee80211_i.h"
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#include "driver-ops.h"
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static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
					  struct ieee80211_chanctx *ctx)
{
	struct ieee80211_sub_if_data *sdata;
	int num = 0;

	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(sdata, &ctx->assigned_vifs, assigned_chanctx_list)
		num++;

	return num;
}

static int ieee80211_chanctx_num_reserved(struct ieee80211_local *local,
					  struct ieee80211_chanctx *ctx)
{
	struct ieee80211_sub_if_data *sdata;
	int num = 0;

	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(sdata, &ctx->reserved_vifs, reserved_chanctx_list)
		num++;

	return num;
}

int ieee80211_chanctx_refcount(struct ieee80211_local *local,
			       struct ieee80211_chanctx *ctx)
{
	return ieee80211_chanctx_num_assigned(local, ctx) +
	       ieee80211_chanctx_num_reserved(local, ctx);
}

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static int ieee80211_num_chanctx(struct ieee80211_local *local)
{
	struct ieee80211_chanctx *ctx;
	int num = 0;

	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(ctx, &local->chanctx_list, list)
		num++;

	return num;
}

static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
{
	lockdep_assert_held(&local->chanctx_mtx);
	return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
}

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static struct ieee80211_chanctx *
ieee80211_vif_get_chanctx(struct ieee80211_sub_if_data *sdata)
{
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	struct ieee80211_local *local __maybe_unused = sdata->local;
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	struct ieee80211_chanctx_conf *conf;

	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	if (!conf)
		return NULL;

	return container_of(conf, struct ieee80211_chanctx, conf);
}

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static const struct cfg80211_chan_def *
ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local,
				   struct ieee80211_chanctx *ctx,
				   const struct cfg80211_chan_def *compat)
{
	struct ieee80211_sub_if_data *sdata;

	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(sdata, &ctx->reserved_vifs,
			    reserved_chanctx_list) {
		if (!compat)
			compat = &sdata->reserved_chandef;

		compat = cfg80211_chandef_compatible(&sdata->reserved_chandef,
						     compat);
		if (!compat)
			break;
	}

	return compat;
}

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static const struct cfg80211_chan_def *
ieee80211_chanctx_non_reserved_chandef(struct ieee80211_local *local,
				       struct ieee80211_chanctx *ctx,
				       const struct cfg80211_chan_def *compat)
{
	struct ieee80211_sub_if_data *sdata;

	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(sdata, &ctx->assigned_vifs,
			    assigned_chanctx_list) {
		if (sdata->reserved_chanctx != NULL)
			continue;

		if (!compat)
			compat = &sdata->vif.bss_conf.chandef;

		compat = cfg80211_chandef_compatible(
				&sdata->vif.bss_conf.chandef, compat);
		if (!compat)
			break;
	}

	return compat;
}

static const struct cfg80211_chan_def *
ieee80211_chanctx_combined_chandef(struct ieee80211_local *local,
				   struct ieee80211_chanctx *ctx,
				   const struct cfg80211_chan_def *compat)
{
	lockdep_assert_held(&local->chanctx_mtx);

	compat = ieee80211_chanctx_reserved_chandef(local, ctx, compat);
	if (!compat)
		return NULL;

	compat = ieee80211_chanctx_non_reserved_chandef(local, ctx, compat);
	if (!compat)
		return NULL;

	return compat;
}

static bool
ieee80211_chanctx_can_reserve_chandef(struct ieee80211_local *local,
				      struct ieee80211_chanctx *ctx,
				      const struct cfg80211_chan_def *def)
{
	lockdep_assert_held(&local->chanctx_mtx);

	if (ieee80211_chanctx_combined_chandef(local, ctx, def))
		return true;

	if (!list_empty(&ctx->reserved_vifs) &&
	    ieee80211_chanctx_reserved_chandef(local, ctx, def))
		return true;

	return false;
}

static struct ieee80211_chanctx *
ieee80211_find_reservation_chanctx(struct ieee80211_local *local,
				   const struct cfg80211_chan_def *chandef,
				   enum ieee80211_chanctx_mode mode)
{
	struct ieee80211_chanctx *ctx;

	lockdep_assert_held(&local->chanctx_mtx);

	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
		return NULL;

	list_for_each_entry(ctx, &local->chanctx_list, list) {
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		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
			continue;

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		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
			continue;

		if (!ieee80211_chanctx_can_reserve_chandef(local, ctx,
							   chandef))
			continue;

		return ctx;
	}

	return NULL;
}

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static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta)
{
	switch (sta->bandwidth) {
	case IEEE80211_STA_RX_BW_20:
		if (sta->ht_cap.ht_supported)
			return NL80211_CHAN_WIDTH_20;
		else
			return NL80211_CHAN_WIDTH_20_NOHT;
	case IEEE80211_STA_RX_BW_40:
		return NL80211_CHAN_WIDTH_40;
	case IEEE80211_STA_RX_BW_80:
		return NL80211_CHAN_WIDTH_80;
	case IEEE80211_STA_RX_BW_160:
		/*
		 * This applied for both 160 and 80+80. since we use
		 * the returned value to consider degradation of
		 * ctx->conf.min_def, we have to make sure to take
		 * the bigger one (NL80211_CHAN_WIDTH_160).
		 * Otherwise we might try degrading even when not
		 * needed, as the max required sta_bw returned (80+80)
		 * might be smaller than the configured bw (160).
		 */
		return NL80211_CHAN_WIDTH_160;
	default:
		WARN_ON(1);
		return NL80211_CHAN_WIDTH_20;
	}
}

static enum nl80211_chan_width
ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
{
	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;
	struct sta_info *sta;

	rcu_read_lock();
	list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
		if (sdata != sta->sdata &&
		    !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
			continue;

		if (!sta->uploaded)
			continue;

		max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
	}
	rcu_read_unlock();

	return max_bw;
}

static enum nl80211_chan_width
ieee80211_get_chanctx_max_required_bw(struct ieee80211_local *local,
				      struct ieee80211_chanctx_conf *conf)
{
	struct ieee80211_sub_if_data *sdata;
	enum nl80211_chan_width max_bw = NL80211_CHAN_WIDTH_20_NOHT;

	rcu_read_lock();
	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
		struct ieee80211_vif *vif = &sdata->vif;
		enum nl80211_chan_width width = NL80211_CHAN_WIDTH_20_NOHT;

		if (!ieee80211_sdata_running(sdata))
			continue;

		if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
			continue;

		switch (vif->type) {
		case NL80211_IFTYPE_AP:
		case NL80211_IFTYPE_AP_VLAN:
			width = ieee80211_get_max_required_bw(sdata);
			break;
		case NL80211_IFTYPE_P2P_DEVICE:
			continue;
		case NL80211_IFTYPE_STATION:
		case NL80211_IFTYPE_ADHOC:
		case NL80211_IFTYPE_WDS:
		case NL80211_IFTYPE_MESH_POINT:
			width = vif->bss_conf.chandef.width;
			break;
		case NL80211_IFTYPE_UNSPECIFIED:
		case NUM_NL80211_IFTYPES:
		case NL80211_IFTYPE_MONITOR:
		case NL80211_IFTYPE_P2P_CLIENT:
		case NL80211_IFTYPE_P2P_GO:
			WARN_ON_ONCE(1);
		}
		max_bw = max(max_bw, width);
	}
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	/* use the configured bandwidth in case of monitor interface */
	sdata = rcu_dereference(local->monitor_sdata);
	if (sdata && rcu_access_pointer(sdata->vif.chanctx_conf) == conf)
		max_bw = max(max_bw, conf->def.width);

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	rcu_read_unlock();

	return max_bw;
}

/*
 * recalc the min required chan width of the channel context, which is
 * the max of min required widths of all the interfaces bound to this
 * channel context.
 */
void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
				      struct ieee80211_chanctx *ctx)
{
	enum nl80211_chan_width max_bw;
	struct cfg80211_chan_def min_def;

	lockdep_assert_held(&local->chanctx_mtx);

	/* don't optimize 5MHz, 10MHz, and radar_enabled confs */
	if (ctx->conf.def.width == NL80211_CHAN_WIDTH_5 ||
	    ctx->conf.def.width == NL80211_CHAN_WIDTH_10 ||
	    ctx->conf.radar_enabled) {
		ctx->conf.min_def = ctx->conf.def;
		return;
	}

	max_bw = ieee80211_get_chanctx_max_required_bw(local, &ctx->conf);

	/* downgrade chandef up to max_bw */
	min_def = ctx->conf.def;
	while (min_def.width > max_bw)
		ieee80211_chandef_downgrade(&min_def);

	if (cfg80211_chandef_identical(&ctx->conf.min_def, &min_def))
		return;

	ctx->conf.min_def = min_def;
	if (!ctx->driver_present)
		return;

	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
}

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static void ieee80211_change_chanctx(struct ieee80211_local *local,
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				     struct ieee80211_chanctx *ctx,
				     const struct cfg80211_chan_def *chandef)
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{
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	if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
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		return;
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	WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));

	ctx->conf.def = *chandef;
	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
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	ieee80211_recalc_chanctx_min_def(local, ctx);
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	if (!local->use_chanctx) {
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		local->_oper_chandef = *chandef;
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		ieee80211_hw_config(local, 0);
	}
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}
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static struct ieee80211_chanctx *
ieee80211_find_chanctx(struct ieee80211_local *local,
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		       const struct cfg80211_chan_def *chandef,
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		       enum ieee80211_chanctx_mode mode)
{
	struct ieee80211_chanctx *ctx;

	lockdep_assert_held(&local->chanctx_mtx);

	if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
		return NULL;

	list_for_each_entry(ctx, &local->chanctx_list, list) {
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		const struct cfg80211_chan_def *compat;
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		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACE_NONE)
			continue;

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		if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
			continue;
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		compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
		if (!compat)
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			continue;

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		compat = ieee80211_chanctx_reserved_chandef(local, ctx,
							    compat);
		if (!compat)
			continue;

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		ieee80211_change_chanctx(local, ctx, compat);
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		return ctx;
	}

	return NULL;
}

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static bool ieee80211_is_radar_required(struct ieee80211_local *local)
{
	struct ieee80211_sub_if_data *sdata;

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	lockdep_assert_held(&local->mtx);

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	rcu_read_lock();
	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
		if (sdata->radar_required) {
			rcu_read_unlock();
			return true;
		}
	}
	rcu_read_unlock();

	return false;
}

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static struct ieee80211_chanctx *
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ieee80211_alloc_chanctx(struct ieee80211_local *local,
			const struct cfg80211_chan_def *chandef,
			enum ieee80211_chanctx_mode mode)
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{
	struct ieee80211_chanctx *ctx;

	lockdep_assert_held(&local->chanctx_mtx);

	ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
	if (!ctx)
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		return NULL;
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	INIT_LIST_HEAD(&ctx->assigned_vifs);
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	INIT_LIST_HEAD(&ctx->reserved_vifs);
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	ctx->conf.def = *chandef;
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	ctx->conf.rx_chains_static = 1;
	ctx->conf.rx_chains_dynamic = 1;
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	ctx->mode = mode;
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	ctx->conf.radar_enabled = ieee80211_is_radar_required(local);
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	ieee80211_recalc_chanctx_min_def(local, ctx);
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	return ctx;
}

static int ieee80211_add_chanctx(struct ieee80211_local *local,
				 struct ieee80211_chanctx *ctx)
{
	u32 changed;
	int err;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

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	if (!local->use_chanctx)
		local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
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	/* turn idle off *before* setting channel -- some drivers need that */
	changed = ieee80211_idle_off(local);
	if (changed)
		ieee80211_hw_config(local, changed);

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	if (!local->use_chanctx) {
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		local->_oper_chandef = ctx->conf.def;
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		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
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	} else {
		err = drv_add_chanctx(local, ctx);
		if (err) {
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			ieee80211_recalc_idle(local);
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			return err;
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		}
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	}

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	return 0;
}

static struct ieee80211_chanctx *
ieee80211_new_chanctx(struct ieee80211_local *local,
		      const struct cfg80211_chan_def *chandef,
		      enum ieee80211_chanctx_mode mode)
{
	struct ieee80211_chanctx *ctx;
	int err;
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	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);
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	ctx = ieee80211_alloc_chanctx(local, chandef, mode);
	if (!ctx)
		return ERR_PTR(-ENOMEM);

	err = ieee80211_add_chanctx(local, ctx);
	if (err) {
		kfree(ctx);
		return ERR_PTR(err);
	}

	list_add_rcu(&ctx->list, &local->chanctx_list);
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	return ctx;
}

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static void ieee80211_del_chanctx(struct ieee80211_local *local,
				  struct ieee80211_chanctx *ctx)
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{
	lockdep_assert_held(&local->chanctx_mtx);

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	if (!local->use_chanctx) {
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		struct cfg80211_chan_def *chandef = &local->_oper_chandef;
		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
		chandef->center_freq1 = chandef->chan->center_freq;
		chandef->center_freq2 = 0;
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		/* NOTE: Disabling radar is only valid here for
		 * single channel context. To be sure, check it ...
		 */
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		WARN_ON(local->hw.conf.radar_enabled &&
			!list_empty(&local->chanctx_list));

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		local->hw.conf.radar_enabled = false;

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		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
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	} else {
		drv_remove_chanctx(local, ctx);
	}
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	ieee80211_recalc_idle(local);
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}

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static void ieee80211_free_chanctx(struct ieee80211_local *local,
				   struct ieee80211_chanctx *ctx)
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{
	lockdep_assert_held(&local->chanctx_mtx);

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	WARN_ON_ONCE(ieee80211_chanctx_refcount(local, ctx) != 0);
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	list_del_rcu(&ctx->list);
	ieee80211_del_chanctx(local, ctx);
	kfree_rcu(ctx, rcu_head);
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}

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static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
					      struct ieee80211_chanctx *ctx)
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{
	struct ieee80211_chanctx_conf *conf = &ctx->conf;
	struct ieee80211_sub_if_data *sdata;
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	const struct cfg80211_chan_def *compat = NULL;
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	lockdep_assert_held(&local->chanctx_mtx);

	rcu_read_lock();
	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
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		if (!ieee80211_sdata_running(sdata))
			continue;
		if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
			continue;

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		if (!compat)
			compat = &sdata->vif.bss_conf.chandef;

		compat = cfg80211_chandef_compatible(
				&sdata->vif.bss_conf.chandef, compat);
		if (!compat)
			break;
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	}
	rcu_read_unlock();

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	if (WARN_ON_ONCE(!compat))
		return;
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	ieee80211_change_chanctx(local, ctx, compat);
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}

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static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
					   struct ieee80211_chanctx *chanctx)
{
	bool radar_enabled;

	lockdep_assert_held(&local->chanctx_mtx);
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	/* for setting local->radar_detect_enabled */
	lockdep_assert_held(&local->mtx);
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	radar_enabled = ieee80211_is_radar_required(local);

	if (radar_enabled == chanctx->conf.radar_enabled)
		return;

	chanctx->conf.radar_enabled = radar_enabled;
	local->radar_detect_enabled = chanctx->conf.radar_enabled;

	if (!local->use_chanctx) {
		local->hw.conf.radar_enabled = chanctx->conf.radar_enabled;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
	}

	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR);
}

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static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
					struct ieee80211_chanctx *new_ctx)
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{
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	struct ieee80211_local *local = sdata->local;
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	struct ieee80211_chanctx_conf *conf;
	struct ieee80211_chanctx *curr_ctx = NULL;
	int ret = 0;
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	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
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	if (conf) {
		curr_ctx = container_of(conf, struct ieee80211_chanctx, conf);
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		drv_unassign_vif_chanctx(local, sdata, curr_ctx);
		conf = NULL;
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		list_del(&sdata->assigned_chanctx_list);
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	}
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	if (new_ctx) {
		ret = drv_assign_vif_chanctx(local, sdata, new_ctx);
		if (ret)
			goto out;
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		conf = &new_ctx->conf;
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		list_add(&sdata->assigned_chanctx_list,
			 &new_ctx->assigned_vifs);
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	}
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out:
	rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
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	sdata->vif.bss_conf.idle = !conf;

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	if (curr_ctx && ieee80211_chanctx_num_assigned(local, curr_ctx) > 0) {
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		ieee80211_recalc_chanctx_chantype(local, curr_ctx);
		ieee80211_recalc_smps_chanctx(local, curr_ctx);
		ieee80211_recalc_radar_chanctx(local, curr_ctx);
		ieee80211_recalc_chanctx_min_def(local, curr_ctx);
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	}
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	if (new_ctx && ieee80211_chanctx_num_assigned(local, new_ctx) > 0) {
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		ieee80211_recalc_txpower(sdata);
		ieee80211_recalc_chanctx_min_def(local, new_ctx);
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	}
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	if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
	    sdata->vif.type != NL80211_IFTYPE_MONITOR)
		ieee80211_bss_info_change_notify(sdata,
						 BSS_CHANGED_IDLE);

	return ret;
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}

static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx_conf *conf;
	struct ieee80211_chanctx *ctx;
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	bool use_reserved_switch = false;
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	lockdep_assert_held(&local->chanctx_mtx);

	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	if (!conf)
		return;

	ctx = container_of(conf, struct ieee80211_chanctx, conf);

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	if (sdata->reserved_chanctx) {
		if (sdata->reserved_chanctx->replace_state ==
		    IEEE80211_CHANCTX_REPLACES_OTHER &&
		    ieee80211_chanctx_num_reserved(local,
						   sdata->reserved_chanctx) > 1)
			use_reserved_switch = true;

663
		ieee80211_vif_unreserve_chanctx(sdata);
664
	}
665

666
	ieee80211_assign_vif_chanctx(sdata, NULL);
667
	if (ieee80211_chanctx_refcount(local, ctx) == 0)
668
		ieee80211_free_chanctx(local, ctx);
669 670 671 672

	/* Unreserving may ready an in-place reservation. */
	if (use_reserved_switch)
		ieee80211_vif_use_reserved_switch(local);
673 674
}

675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736
void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
				   struct ieee80211_chanctx *chanctx)
{
	struct ieee80211_sub_if_data *sdata;
	u8 rx_chains_static, rx_chains_dynamic;

	lockdep_assert_held(&local->chanctx_mtx);

	rx_chains_static = 1;
	rx_chains_dynamic = 1;

	rcu_read_lock();
	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
		u8 needed_static, needed_dynamic;

		if (!ieee80211_sdata_running(sdata))
			continue;

		if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
						&chanctx->conf)
			continue;

		switch (sdata->vif.type) {
		case NL80211_IFTYPE_P2P_DEVICE:
			continue;
		case NL80211_IFTYPE_STATION:
			if (!sdata->u.mgd.associated)
				continue;
			break;
		case NL80211_IFTYPE_AP_VLAN:
			continue;
		case NL80211_IFTYPE_AP:
		case NL80211_IFTYPE_ADHOC:
		case NL80211_IFTYPE_WDS:
		case NL80211_IFTYPE_MESH_POINT:
			break;
		default:
			WARN_ON_ONCE(1);
		}

		switch (sdata->smps_mode) {
		default:
			WARN_ONCE(1, "Invalid SMPS mode %d\n",
				  sdata->smps_mode);
			/* fall through */
		case IEEE80211_SMPS_OFF:
			needed_static = sdata->needed_rx_chains;
			needed_dynamic = sdata->needed_rx_chains;
			break;
		case IEEE80211_SMPS_DYNAMIC:
			needed_static = 1;
			needed_dynamic = sdata->needed_rx_chains;
			break;
		case IEEE80211_SMPS_STATIC:
			needed_static = 1;
			needed_dynamic = 1;
			break;
		}

		rx_chains_static = max(rx_chains_static, needed_static);
		rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
	}
737 738 739 740 741 742 743

	/* Disable SMPS for the monitor interface */
	sdata = rcu_dereference(local->monitor_sdata);
	if (sdata &&
	    rcu_access_pointer(sdata->vif.chanctx_conf) == &chanctx->conf)
		rx_chains_dynamic = rx_chains_static = local->rx_chains;

744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764
	rcu_read_unlock();

	if (!local->use_chanctx) {
		if (rx_chains_static > 1)
			local->smps_mode = IEEE80211_SMPS_OFF;
		else if (rx_chains_dynamic > 1)
			local->smps_mode = IEEE80211_SMPS_DYNAMIC;
		else
			local->smps_mode = IEEE80211_SMPS_STATIC;
		ieee80211_hw_config(local, 0);
	}

	if (rx_chains_static == chanctx->conf.rx_chains_static &&
	    rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
		return;

	chanctx->conf.rx_chains_static = rx_chains_static;
	chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
	drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
}

765
int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
766
			      const struct cfg80211_chan_def *chandef,
767 768 769 770
			      enum ieee80211_chanctx_mode mode)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx *ctx;
771
	u8 radar_detect_width = 0;
772 773
	int ret;

774 775
	lockdep_assert_held(&local->mtx);

J
Johannes Berg 已提交
776 777
	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));

778
	mutex_lock(&local->chanctx_mtx);
779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794

	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
					    chandef,
					    sdata->wdev.iftype);
	if (ret < 0)
		goto out;
	if (ret > 0)
		radar_detect_width = BIT(chandef->width);

	sdata->radar_required = ret;

	ret = ieee80211_check_combinations(sdata, chandef, mode,
					   radar_detect_width);
	if (ret < 0)
		goto out;

795 796
	__ieee80211_vif_release_channel(sdata);

797
	ctx = ieee80211_find_chanctx(local, chandef, mode);
798
	if (!ctx)
799
		ctx = ieee80211_new_chanctx(local, chandef, mode);
800 801 802 803 804
	if (IS_ERR(ctx)) {
		ret = PTR_ERR(ctx);
		goto out;
	}

805
	sdata->vif.bss_conf.chandef = *chandef;
J
Johannes Berg 已提交
806

807 808 809
	ret = ieee80211_assign_vif_chanctx(sdata, ctx);
	if (ret) {
		/* if assign fails refcount stays the same */
810
		if (ieee80211_chanctx_refcount(local, ctx) == 0)
811 812 813 814
			ieee80211_free_chanctx(local, ctx);
		goto out;
	}

815
	ieee80211_recalc_smps_chanctx(local, ctx);
816
	ieee80211_recalc_radar_chanctx(local, ctx);
817 818 819 820 821
 out:
	mutex_unlock(&local->chanctx_mtx);
	return ret;
}

822 823 824 825
static void
__ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
				      bool clear)
{
826
	struct ieee80211_local *local __maybe_unused = sdata->local;
827 828 829 830 831 832 833 834 835 836 837 838 839 840 841
	struct ieee80211_sub_if_data *vlan;
	struct ieee80211_chanctx_conf *conf;

	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
		return;

	lockdep_assert_held(&local->mtx);

	/* Check that conf exists, even when clearing this function
	 * must be called with the AP's channel context still there
	 * as it would otherwise cause VLANs to have an invalid
	 * channel context pointer for a while, possibly pointing
	 * to a channel context that has already been freed.
	 */
	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
842
					 lockdep_is_held(&local->chanctx_mtx));
843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865
	WARN_ON(!conf);

	if (clear)
		conf = NULL;

	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
		rcu_assign_pointer(vlan->vif.chanctx_conf, conf);
}

void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata,
					 bool clear)
{
	struct ieee80211_local *local = sdata->local;

	mutex_lock(&local->chanctx_mtx);

	__ieee80211_vif_copy_chanctx_to_vlans(sdata, clear);

	mutex_unlock(&local->chanctx_mtx);
}

int ieee80211_vif_unreserve_chanctx(struct ieee80211_sub_if_data *sdata)
{
866 867
	struct ieee80211_chanctx *ctx = sdata->reserved_chanctx;

868 869
	lockdep_assert_held(&sdata->local->chanctx_mtx);

870
	if (WARN_ON(!ctx))
871 872
		return -EINVAL;

873
	list_del(&sdata->reserved_chanctx_list);
874 875
	sdata->reserved_chanctx = NULL;

876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894
	if (ieee80211_chanctx_refcount(sdata->local, ctx) == 0) {
		if (ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
			if (WARN_ON(!ctx->replace_ctx))
				return -EINVAL;

			WARN_ON(ctx->replace_ctx->replace_state !=
			        IEEE80211_CHANCTX_WILL_BE_REPLACED);
			WARN_ON(ctx->replace_ctx->replace_ctx != ctx);

			ctx->replace_ctx->replace_ctx = NULL;
			ctx->replace_ctx->replace_state =
					IEEE80211_CHANCTX_REPLACE_NONE;

			list_del_rcu(&ctx->list);
			kfree_rcu(ctx, rcu_head);
		} else {
			ieee80211_free_chanctx(sdata->local, ctx);
		}
	}
895

896 897 898 899 900
	return 0;
}

int ieee80211_vif_reserve_chanctx(struct ieee80211_sub_if_data *sdata,
				  const struct cfg80211_chan_def *chandef,
901 902
				  enum ieee80211_chanctx_mode mode,
				  bool radar_required)
903 904
{
	struct ieee80211_local *local = sdata->local;
905
	struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
906

907
	lockdep_assert_held(&local->chanctx_mtx);
908

909 910 911
	curr_ctx = ieee80211_vif_get_chanctx(sdata);
	if (curr_ctx && local->use_chanctx && !local->ops->switch_vif_chanctx)
		return -ENOTSUPP;
912

913
	new_ctx = ieee80211_find_reservation_chanctx(local, chandef, mode);
914
	if (!new_ctx) {
915
		if (ieee80211_can_create_new_chanctx(local)) {
916
			new_ctx = ieee80211_new_chanctx(local, chandef, mode);
917 918
			if (IS_ERR(new_ctx))
				return PTR_ERR(new_ctx);
919
		} else {
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982
			if (!curr_ctx ||
			    (curr_ctx->replace_state ==
			     IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
			    !list_empty(&curr_ctx->reserved_vifs)) {
				/*
				 * Another vif already requested this context
				 * for a reservation. Find another one hoping
				 * all vifs assigned to it will also switch
				 * soon enough.
				 *
				 * TODO: This needs a little more work as some
				 * cases (more than 2 chanctx capable devices)
				 * may fail which could otherwise succeed
				 * provided some channel context juggling was
				 * performed.
				 *
				 * Consider ctx1..3, vif1..6, each ctx has 2
				 * vifs. vif1 and vif2 from ctx1 request new
				 * different chandefs starting 2 in-place
				 * reserations with ctx4 and ctx5 replacing
				 * ctx1 and ctx2 respectively. Next vif5 and
				 * vif6 from ctx3 reserve ctx4. If vif3 and
				 * vif4 remain on ctx2 as they are then this
				 * fails unless `replace_ctx` from ctx5 is
				 * replaced with ctx3.
				 */
				list_for_each_entry(ctx, &local->chanctx_list,
						    list) {
					if (ctx->replace_state !=
					    IEEE80211_CHANCTX_REPLACE_NONE)
						continue;

					if (!list_empty(&ctx->reserved_vifs))
						continue;

					curr_ctx = ctx;
					break;
				}
			}

			/*
			 * If that's true then all available contexts already
			 * have reservations and cannot be used.
			 */
			if (!curr_ctx ||
			    (curr_ctx->replace_state ==
			     IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
			    !list_empty(&curr_ctx->reserved_vifs))
				return -EBUSY;

			new_ctx = ieee80211_alloc_chanctx(local, chandef, mode);
			if (!new_ctx)
				return -ENOMEM;

			new_ctx->replace_ctx = curr_ctx;
			new_ctx->replace_state =
					IEEE80211_CHANCTX_REPLACES_OTHER;

			curr_ctx->replace_ctx = new_ctx;
			curr_ctx->replace_state =
					IEEE80211_CHANCTX_WILL_BE_REPLACED;

			list_add_rcu(&new_ctx->list, &local->chanctx_list);
983 984 985
		}
	}

986
	list_add(&sdata->reserved_chanctx_list, &new_ctx->reserved_vifs);
987 988
	sdata->reserved_chanctx = new_ctx;
	sdata->reserved_chandef = *chandef;
989
	sdata->reserved_radar_required = radar_required;
990 991 992
	sdata->reserved_ready = false;

	return 0;
993 994
}

995 996 997 998 999 1000 1001 1002 1003 1004 1005
static void
ieee80211_vif_chanctx_reservation_complete(struct ieee80211_sub_if_data *sdata)
{
	switch (sdata->vif.type) {
	case NL80211_IFTYPE_ADHOC:
	case NL80211_IFTYPE_AP:
	case NL80211_IFTYPE_MESH_POINT:
		ieee80211_queue_work(&sdata->local->hw,
				     &sdata->csa_finalize_work);
		break;
	case NL80211_IFTYPE_STATION:
1006 1007 1008 1009
		ieee80211_queue_work(&sdata->local->hw,
				     &sdata->u.mgd.chswitch_work);
		break;
	case NL80211_IFTYPE_UNSPECIFIED:
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021
	case NL80211_IFTYPE_AP_VLAN:
	case NL80211_IFTYPE_WDS:
	case NL80211_IFTYPE_MONITOR:
	case NL80211_IFTYPE_P2P_CLIENT:
	case NL80211_IFTYPE_P2P_GO:
	case NL80211_IFTYPE_P2P_DEVICE:
	case NUM_NL80211_IFTYPES:
		WARN_ON(1);
		break;
	}
}

1022 1023
static int
ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
1024 1025
{
	struct ieee80211_local *local = sdata->local;
1026 1027 1028 1029 1030
	struct ieee80211_vif_chanctx_switch vif_chsw[1] = {};
	struct ieee80211_chanctx *old_ctx, *new_ctx;
	const struct cfg80211_chan_def *chandef;
	u32 changed = 0;
	int err;
1031 1032

	lockdep_assert_held(&local->mtx);
1033
	lockdep_assert_held(&local->chanctx_mtx);
1034

1035 1036
	new_ctx = sdata->reserved_chanctx;
	old_ctx = ieee80211_vif_get_chanctx(sdata);
1037

1038 1039
	if (WARN_ON(!sdata->reserved_ready))
		return -EBUSY;
1040

1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068
	if (WARN_ON(!new_ctx))
		return -EINVAL;

	if (WARN_ON(!old_ctx))
		return -EINVAL;

	if (WARN_ON(new_ctx->replace_state ==
		    IEEE80211_CHANCTX_REPLACES_OTHER))
		return -EINVAL;

	chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
				&sdata->reserved_chandef);
	if (WARN_ON(!chandef))
		return -EINVAL;

	vif_chsw[0].vif = &sdata->vif;
	vif_chsw[0].old_ctx = &old_ctx->conf;
	vif_chsw[0].new_ctx = &new_ctx->conf;

	list_del(&sdata->reserved_chanctx_list);
	sdata->reserved_chanctx = NULL;

	err = drv_switch_vif_chanctx(local, vif_chsw, 1,
				     CHANCTX_SWMODE_REASSIGN_VIF);
	if (err) {
		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
			ieee80211_free_chanctx(local, new_ctx);

1069
		goto out;
1070 1071
	}

1072 1073 1074 1075 1076 1077 1078 1079
	list_move(&sdata->assigned_chanctx_list, &new_ctx->assigned_vifs);
	rcu_assign_pointer(sdata->vif.chanctx_conf, &new_ctx->conf);

	if (sdata->vif.type == NL80211_IFTYPE_AP)
		__ieee80211_vif_copy_chanctx_to_vlans(sdata, false);

	if (ieee80211_chanctx_refcount(local, old_ctx) == 0)
		ieee80211_free_chanctx(local, old_ctx);
1080

1081
	if (sdata->vif.bss_conf.chandef.width != sdata->reserved_chandef.width)
1082
		changed = BSS_CHANGED_BANDWIDTH;
1083 1084 1085

	sdata->vif.bss_conf.chandef = sdata->reserved_chandef;

1086 1087 1088
	if (changed)
		ieee80211_bss_info_change_notify(sdata, changed);

1089 1090
out:
	ieee80211_vif_chanctx_reservation_complete(sdata);
1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122
	return err;
}

static int
ieee80211_vif_use_reserved_assign(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx *old_ctx, *new_ctx;
	const struct cfg80211_chan_def *chandef;
	int err;

	old_ctx = ieee80211_vif_get_chanctx(sdata);
	new_ctx = sdata->reserved_chanctx;

	if (WARN_ON(!sdata->reserved_ready))
		return -EINVAL;

	if (WARN_ON(old_ctx))
		return -EINVAL;

	if (WARN_ON(!new_ctx))
		return -EINVAL;

	if (WARN_ON(new_ctx->replace_state ==
		    IEEE80211_CHANCTX_REPLACES_OTHER))
		return -EINVAL;

	chandef = ieee80211_chanctx_non_reserved_chandef(local, new_ctx,
				&sdata->reserved_chandef);
	if (WARN_ON(!chandef))
		return -EINVAL;

1123
	list_del(&sdata->reserved_chanctx_list);
1124
	sdata->reserved_chanctx = NULL;
1125

1126 1127 1128 1129 1130 1131 1132 1133 1134
	err = ieee80211_assign_vif_chanctx(sdata, new_ctx);
	if (err) {
		if (ieee80211_chanctx_refcount(local, new_ctx) == 0)
			ieee80211_free_chanctx(local, new_ctx);

		goto out;
	}

out:
1135
	ieee80211_vif_chanctx_reservation_complete(sdata);
1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204
	return err;
}

static bool
ieee80211_vif_has_in_place_reservation(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_chanctx *old_ctx, *new_ctx;

	lockdep_assert_held(&sdata->local->chanctx_mtx);

	new_ctx = sdata->reserved_chanctx;
	old_ctx = ieee80211_vif_get_chanctx(sdata);

	if (!old_ctx)
		return false;

	if (WARN_ON(!new_ctx))
		return false;

	if (old_ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
		return false;

	if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
		return false;

	return true;
}

static int ieee80211_chsw_switch_hwconf(struct ieee80211_local *local,
					struct ieee80211_chanctx *new_ctx)
{
	const struct cfg80211_chan_def *chandef;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

	chandef = ieee80211_chanctx_reserved_chandef(local, new_ctx, NULL);
	if (WARN_ON(!chandef))
		return -EINVAL;

	local->hw.conf.radar_enabled = new_ctx->conf.radar_enabled;
	local->_oper_chandef = *chandef;
	ieee80211_hw_config(local, 0);

	return 0;
}

static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local,
				      int n_vifs)
{
	struct ieee80211_vif_chanctx_switch *vif_chsw;
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_chanctx *ctx, *old_ctx;
	int i, err;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

	vif_chsw = kzalloc(sizeof(vif_chsw[0]) * n_vifs, GFP_KERNEL);
	if (!vif_chsw)
		return -ENOMEM;

	i = 0;
	list_for_each_entry(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		if (WARN_ON(!ctx->replace_ctx)) {
			err = -EINVAL;
1205 1206
			goto out;
		}
1207

1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220
		list_for_each_entry(sdata, &ctx->reserved_vifs,
				    reserved_chanctx_list) {
			if (!ieee80211_vif_has_in_place_reservation(
					sdata))
				continue;

			old_ctx = ieee80211_vif_get_chanctx(sdata);
			vif_chsw[i].vif = &sdata->vif;
			vif_chsw[i].old_ctx = &old_ctx->conf;
			vif_chsw[i].new_ctx = &ctx->conf;

			i++;
		}
1221
	}
1222

1223 1224
	err = drv_switch_vif_chanctx(local, vif_chsw, n_vifs,
				     CHANCTX_SWMODE_SWAP_CONTEXTS);
1225

1226
out:
1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448
	kfree(vif_chsw);
	return err;
}

static int ieee80211_chsw_switch_ctxs(struct ieee80211_local *local)
{
	struct ieee80211_chanctx *ctx;
	int err;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

	list_for_each_entry(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		if (!list_empty(&ctx->replace_ctx->assigned_vifs))
			continue;

		ieee80211_del_chanctx(local, ctx->replace_ctx);
		err = ieee80211_add_chanctx(local, ctx);
		if (err)
			goto err;
	}

	return 0;

err:
	WARN_ON(ieee80211_add_chanctx(local, ctx));
	list_for_each_entry_continue_reverse(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		if (!list_empty(&ctx->replace_ctx->assigned_vifs))
			continue;

		ieee80211_del_chanctx(local, ctx);
		WARN_ON(ieee80211_add_chanctx(local, ctx->replace_ctx));
	}

	return err;
}

int
ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
{
	struct ieee80211_sub_if_data *sdata, *sdata_tmp;
	struct ieee80211_chanctx *ctx, *ctx_tmp, *old_ctx;
	struct ieee80211_chanctx *new_ctx = NULL;
	int i, err, n_assigned, n_reserved, n_ready;
	int n_ctx = 0, n_vifs_switch = 0, n_vifs_assign = 0, n_vifs_ctxless = 0;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

	/*
	 * If there are 2 independent pairs of channel contexts performing
	 * cross-switch of their vifs this code will still wait until both are
	 * ready even though it could be possible to switch one before the
	 * other is ready.
	 *
	 * For practical reasons and code simplicity just do a single huge
	 * switch.
	 */

	/*
	 * Verify if the reservation is still feasible.
	 *  - if it's not then disconnect
	 *  - if it is but not all vifs necessary are ready then defer
	 */

	list_for_each_entry(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		if (WARN_ON(!ctx->replace_ctx)) {
			err = -EINVAL;
			goto err;
		}

		if (!local->use_chanctx)
			new_ctx = ctx;

		n_ctx++;

		n_assigned = 0;
		n_reserved = 0;
		n_ready = 0;

		list_for_each_entry(sdata, &ctx->replace_ctx->assigned_vifs,
				    assigned_chanctx_list) {
			n_assigned++;
			if (sdata->reserved_chanctx) {
				n_reserved++;
				if (sdata->reserved_ready)
					n_ready++;
			}
		}

		if (n_assigned != n_reserved) {
			if (n_ready == n_reserved) {
				wiphy_info(local->hw.wiphy,
					   "channel context reservation cannot be finalized because some interfaces aren't switching\n");
				err = -EBUSY;
				goto err;
			}

			return -EAGAIN;
		}

		ctx->conf.radar_enabled = false;
		list_for_each_entry(sdata, &ctx->reserved_vifs,
				    reserved_chanctx_list) {
			if (ieee80211_vif_has_in_place_reservation(sdata) &&
			    !sdata->reserved_ready)
				return -EAGAIN;

			old_ctx = ieee80211_vif_get_chanctx(sdata);
			if (old_ctx) {
				if (old_ctx->replace_state ==
				    IEEE80211_CHANCTX_WILL_BE_REPLACED)
					n_vifs_switch++;
				else
					n_vifs_assign++;
			} else {
				n_vifs_ctxless++;
			}

			if (sdata->reserved_radar_required)
				ctx->conf.radar_enabled = true;
		}
	}

	if (WARN_ON(n_ctx == 0) ||
	    WARN_ON(n_vifs_switch == 0 &&
		    n_vifs_assign == 0 &&
		    n_vifs_ctxless == 0) ||
	    WARN_ON(n_ctx > 1 && !local->use_chanctx) ||
	    WARN_ON(!new_ctx && !local->use_chanctx)) {
		err = -EINVAL;
		goto err;
	}

	/*
	 * All necessary vifs are ready. Perform the switch now depending on
	 * reservations and driver capabilities.
	 */

	if (local->use_chanctx) {
		if (n_vifs_switch > 0) {
			err = ieee80211_chsw_switch_vifs(local, n_vifs_switch);
			if (err)
				goto err;
		}

		if (n_vifs_assign > 0 || n_vifs_ctxless > 0) {
			err = ieee80211_chsw_switch_ctxs(local);
			if (err)
				goto err;
		}
	} else {
		err = ieee80211_chsw_switch_hwconf(local, new_ctx);
		if (err)
			goto err;
	}

	/*
	 * Update all structures, values and pointers to point to new channel
	 * context(s).
	 */

	i = 0;
	list_for_each_entry(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		if (WARN_ON(!ctx->replace_ctx)) {
			err = -EINVAL;
			goto err;
		}

		list_for_each_entry(sdata, &ctx->reserved_vifs,
				    reserved_chanctx_list) {
			u32 changed = 0;

			if (!ieee80211_vif_has_in_place_reservation(sdata))
				continue;

			rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);

			if (sdata->vif.type == NL80211_IFTYPE_AP)
				__ieee80211_vif_copy_chanctx_to_vlans(sdata,
								      false);

			sdata->radar_required = sdata->reserved_radar_required;

			if (sdata->vif.bss_conf.chandef.width !=
			    sdata->reserved_chandef.width)
				changed = BSS_CHANGED_BANDWIDTH;

			sdata->vif.bss_conf.chandef = sdata->reserved_chandef;
			if (changed)
				ieee80211_bss_info_change_notify(sdata,
								 changed);

			ieee80211_recalc_txpower(sdata);
		}

		ieee80211_recalc_chanctx_chantype(local, ctx);
		ieee80211_recalc_smps_chanctx(local, ctx);
		ieee80211_recalc_radar_chanctx(local, ctx);
		ieee80211_recalc_chanctx_min_def(local, ctx);

		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
					 reserved_chanctx_list) {
			if (ieee80211_vif_get_chanctx(sdata) != ctx)
				continue;

			list_del(&sdata->reserved_chanctx_list);
			list_move(&sdata->assigned_chanctx_list,
				  &new_ctx->assigned_vifs);
			sdata->reserved_chanctx = NULL;
1449 1450

			ieee80211_vif_chanctx_reservation_complete(sdata);
1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513
		}

		/*
		 * This context might have been a dependency for an already
		 * ready re-assign reservation interface that was deferred. Do
		 * not propagate error to the caller though. The in-place
		 * reservation for originally requested interface has already
		 * succeeded at this point.
		 */
		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
					 reserved_chanctx_list) {
			if (WARN_ON(ieee80211_vif_has_in_place_reservation(
					sdata)))
				continue;

			if (WARN_ON(sdata->reserved_chanctx != ctx))
				continue;

			if (!sdata->reserved_ready)
				continue;

			if (ieee80211_vif_get_chanctx(sdata))
				err = ieee80211_vif_use_reserved_reassign(
						sdata);
			else
				err = ieee80211_vif_use_reserved_assign(sdata);

			if (err) {
				sdata_info(sdata,
					   "failed to finalize (re-)assign reservation (err=%d)\n",
					   err);
				ieee80211_vif_unreserve_chanctx(sdata);
				cfg80211_stop_iface(local->hw.wiphy,
						    &sdata->wdev,
						    GFP_KERNEL);
			}
		}
	}

	/*
	 * Finally free old contexts
	 */

	list_for_each_entry_safe(ctx, ctx_tmp, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_WILL_BE_REPLACED)
			continue;

		ctx->replace_ctx->replace_ctx = NULL;
		ctx->replace_ctx->replace_state =
				IEEE80211_CHANCTX_REPLACE_NONE;

		list_del_rcu(&ctx->list);
		kfree_rcu(ctx, rcu_head);
	}

	return 0;

err:
	list_for_each_entry(ctx, &local->chanctx_list, list) {
		if (ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER)
			continue;

		list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
1514
					 reserved_chanctx_list) {
1515
			ieee80211_vif_unreserve_chanctx(sdata);
1516 1517
			ieee80211_vif_chanctx_reservation_complete(sdata);
		}
1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584
	}

	return err;
}

int ieee80211_vif_use_reserved_context(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx *new_ctx;
	struct ieee80211_chanctx *old_ctx;
	int err;

	lockdep_assert_held(&local->mtx);
	lockdep_assert_held(&local->chanctx_mtx);

	new_ctx = sdata->reserved_chanctx;
	old_ctx = ieee80211_vif_get_chanctx(sdata);

	if (WARN_ON(!new_ctx))
		return -EINVAL;

	if (WARN_ON(new_ctx->replace_state ==
		    IEEE80211_CHANCTX_WILL_BE_REPLACED))
		return -EINVAL;

	if (WARN_ON(sdata->reserved_ready))
		return -EINVAL;

	sdata->reserved_ready = true;

	if (new_ctx->replace_state == IEEE80211_CHANCTX_REPLACE_NONE) {
		if (old_ctx)
			err = ieee80211_vif_use_reserved_reassign(sdata);
		else
			err = ieee80211_vif_use_reserved_assign(sdata);

		if (err)
			return err;
	}

	/*
	 * In-place reservation may need to be finalized now either if:
	 *  a) sdata is taking part in the swapping itself and is the last one
	 *  b) sdata has switched with a re-assign reservation to an existing
	 *     context readying in-place switching of old_ctx
	 *
	 * In case of (b) do not propagate the error up because the requested
	 * sdata already switched successfully. Just spill an extra warning.
	 * The ieee80211_vif_use_reserved_switch() already stops all necessary
	 * interfaces upon failure.
	 */
	if ((old_ctx &&
	     old_ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
	    new_ctx->replace_state == IEEE80211_CHANCTX_REPLACES_OTHER) {
		err = ieee80211_vif_use_reserved_switch(local);
		if (err && err != -EAGAIN) {
			if (new_ctx->replace_state ==
			    IEEE80211_CHANCTX_REPLACES_OTHER)
				return err;

			wiphy_info(local->hw.wiphy,
				   "depending in-place reservation failed (err=%d)\n",
				   err);
		}
	}

	return 0;
1585 1586
}

1587 1588 1589 1590 1591 1592 1593
int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata,
				   const struct cfg80211_chan_def *chandef,
				   u32 *changed)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_chanctx_conf *conf;
	struct ieee80211_chanctx *ctx;
1594
	const struct cfg80211_chan_def *compat;
1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620
	int ret;

	if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
				     IEEE80211_CHAN_DISABLED))
		return -EINVAL;

	mutex_lock(&local->chanctx_mtx);
	if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) {
		ret = 0;
		goto out;
	}

	if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT ||
	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) {
		ret = -EINVAL;
		goto out;
	}

	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	if (!conf) {
		ret = -EINVAL;
		goto out;
	}

	ctx = container_of(conf, struct ieee80211_chanctx, conf);
1621 1622 1623

	compat = cfg80211_chandef_compatible(&conf->def, chandef);
	if (!compat) {
1624 1625 1626 1627
		ret = -EINVAL;
		goto out;
	}

1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647
	switch (ctx->replace_state) {
	case IEEE80211_CHANCTX_REPLACE_NONE:
		if (!ieee80211_chanctx_reserved_chandef(local, ctx, compat)) {
			ret = -EBUSY;
			goto out;
		}
		break;
	case IEEE80211_CHANCTX_WILL_BE_REPLACED:
		/* TODO: Perhaps the bandwith change could be treated as a
		 * reservation itself? */
		ret = -EBUSY;
		goto out;
	case IEEE80211_CHANCTX_REPLACES_OTHER:
		/* channel context that is going to replace another channel
		 * context doesn't really exist and shouldn't be assigned
		 * anywhere yet */
		WARN_ON(1);
		break;
	}

1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658
	sdata->vif.bss_conf.chandef = *chandef;

	ieee80211_recalc_chanctx_chantype(local, ctx);

	*changed |= BSS_CHANGED_BANDWIDTH;
	ret = 0;
 out:
	mutex_unlock(&local->chanctx_mtx);
	return ret;
}

1659 1660
void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
{
J
Johannes Berg 已提交
1661 1662
	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));

1663 1664
	lockdep_assert_held(&sdata->local->mtx);

1665 1666 1667 1668
	mutex_lock(&sdata->local->chanctx_mtx);
	__ieee80211_vif_release_channel(sdata);
	mutex_unlock(&sdata->local->chanctx_mtx);
}
1669

1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688
void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_sub_if_data *ap;
	struct ieee80211_chanctx_conf *conf;

	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
		return;

	ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);

	mutex_lock(&local->chanctx_mtx);

	conf = rcu_dereference_protected(ap->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
	mutex_unlock(&local->chanctx_mtx);
}

1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700
void ieee80211_iter_chan_contexts_atomic(
	struct ieee80211_hw *hw,
	void (*iter)(struct ieee80211_hw *hw,
		     struct ieee80211_chanctx_conf *chanctx_conf,
		     void *data),
	void *iter_data)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_chanctx *ctx;

	rcu_read_lock();
	list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
1701 1702
		if (ctx->driver_present)
			iter(hw, &ctx->conf, iter_data);
1703 1704 1705
	rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);