mac80211: use channel contexts

Instead of operating on a single channel only,
use the new channel context infrastructure in
all mac80211 code.

This enables drivers that want to use the new
channel context infrastructure to use multiple
channels, while nothing should change for all
the other drivers that don't support it.

Right now this disables both TX power settings
and spatial multiplexing powersave. Both need
to be re-enabled on a channel context basis.

Additionally, when channel contexts are used
drop the connection when channel switch is
received rather than trying to handle it. This
will have to be improved later.

[With fixes from Eliad and Emmanuel incorporated]
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

16 files changed, 586 insertions, 466 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 70a5d262815f..09c90627fd19 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -372,10 +372,11 @@ static int ieee80211_config_default_mgmt_key(struct wiphy *wiphy,
 
 static void rate_idx_to_bitrate(struct rate_info *rate, struct sta_info *sta, int idx)
 {
+	enum ieee80211_band band = ieee80211_get_sdata_band(sta->sdata);
+
 	if (!(rate->flags & RATE_INFO_FLAGS_MCS)) {
 		struct ieee80211_supported_band *sband;
-		sband = sta->local->hw.wiphy->bands[
-				sta->local->oper_channel->band];
+		sband = sta->local->hw.wiphy->bands[band];
 		rate->legacy = sband->bitrates[idx].bitrate;
 	} else
 		rate->mcs = idx;
@@ -532,6 +533,8 @@ static void ieee80211_get_et_stats(struct wiphy *wiphy,
 				   u64 *data)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *channel;
 	struct sta_info *sta;
 	struct ieee80211_local *local = sdata->local;
 	struct station_info sinfo;
@@ -607,19 +610,26 @@ static void ieee80211_get_et_stats(struct wiphy *wiphy,
 do_survey:
 	i = STA_STATS_LEN - STA_STATS_SURVEY_LEN;
 	/* Get survey stats for current channel */
-	q = 0;
-	while (true) {
-		survey.filled = 0;
-		if (drv_get_survey(local, q, &survey) != 0) {
-			survey.filled = 0;
-			break;
-		}
+	survey.filled = 0;
 
-		if (survey.channel &&
-		    (local->oper_channel->center_freq ==
-		     survey.channel->center_freq))
-			break;
-		q++;
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (chanctx_conf)
+		channel = chanctx_conf->channel;
+	else
+		channel = NULL;
+	rcu_read_unlock();
+
+	if (channel) {
+		q = 0;
+		do {
+			survey.filled = 0;
+			if (drv_get_survey(local, q, &survey) != 0) {
+				survey.filled = 0;
+				break;
+			}
+			q++;
+		} while (channel != survey.channel);
 	}
 
 	if (survey.filled)
@@ -724,47 +734,42 @@ static int ieee80211_get_station(struct wiphy *wiphy, struct net_device *dev,
 	return ret;
 }
 
-static int ieee80211_set_channel(struct wiphy *wiphy,
-				 struct net_device *netdev,
-				 struct ieee80211_channel *chan,
-				 enum nl80211_channel_type channel_type)
+static int ieee80211_set_monitor_channel(struct wiphy *wiphy,
+					 struct ieee80211_channel *chan,
+					 enum nl80211_channel_type channel_type)
 {
 	struct ieee80211_local *local = wiphy_priv(wiphy);
-	struct ieee80211_sub_if_data *sdata = NULL;
-
-	if (netdev)
-		sdata = IEEE80211_DEV_TO_SUB_IF(netdev);
-
-	switch (ieee80211_get_channel_mode(local, NULL)) {
-	case CHAN_MODE_HOPPING:
-		return -EBUSY;
-	case CHAN_MODE_FIXED:
-		if (local->oper_channel != chan ||
-		    (!sdata && local->_oper_channel_type != channel_type))
-			return -EBUSY;
-		if (!sdata && local->_oper_channel_type == channel_type)
-			return 0;
-		break;
-	case CHAN_MODE_UNDEFINED:
-		break;
-	}
-
-	if (!ieee80211_set_channel_type(local, sdata, channel_type))
-		return -EBUSY;
+	struct ieee80211_sub_if_data *sdata;
+	int ret = 0;
 
-	local->oper_channel = chan;
+	if (local->monitor_channel == chan &&
+	    local->monitor_channel_type == channel_type)
+		return 0;
 
-	/* auto-detects changes */
-	ieee80211_hw_config(local, 0);
+	mutex_lock(&local->iflist_mtx);
+	if (local->use_chanctx) {
+		sdata = rcu_dereference_protected(
+				local->monitor_sdata,
+				lockdep_is_held(&local->iflist_mtx));
+		if (sdata) {
+			ieee80211_vif_release_channel(sdata);
+			ret = ieee80211_vif_use_channel(
+					sdata, chan, channel_type,
+					IEEE80211_CHANCTX_EXCLUSIVE);
+		}
+	} else if (local->open_count == local->monitors) {
+		local->_oper_channel = chan;
+		local->_oper_channel_type = channel_type;
+		ieee80211_hw_config(local, 0);
+	}
 
-	return 0;
-}
+	if (ret == 0) {
+		local->monitor_channel = chan;
+		local->monitor_channel_type = channel_type;
+	}
+	mutex_unlock(&local->iflist_mtx);
 
-static int ieee80211_set_monitor_channel(struct wiphy *wiphy,
-					 struct ieee80211_channel *chan,
-					 enum nl80211_channel_type channel_type)
-{
-	return ieee80211_set_channel(wiphy, NULL, chan, channel_type);
+	return ret;
 }
 
 static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
@@ -879,8 +884,9 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 	if (old)
 		return -EALREADY;
 
-	err = ieee80211_set_channel(wiphy, dev, params->channel,
-				    params->channel_type);
+	err = ieee80211_vif_use_channel(sdata, params->channel,
+					params->channel_type,
+					IEEE80211_CHANCTX_SHARED);
 	if (err)
 		return err;
 
@@ -963,6 +969,8 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	sta_info_flush(sdata->local, sdata);
 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
 
+	ieee80211_vif_release_channel(sdata);
+
 	return 0;
 }
 
@@ -1019,9 +1027,10 @@ static int sta_apply_parameters(struct ieee80211_local *local,
 	int i, j;
 	struct ieee80211_supported_band *sband;
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
+	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 	u32 mask, set;
 
-	sband = local->hw.wiphy->bands[local->oper_channel->band];
+	sband = local->hw.wiphy->bands[band];
 
 	mask = params->sta_flags_mask;
 	set = params->sta_flags_set;
@@ -1136,7 +1145,7 @@ static int sta_apply_parameters(struct ieee80211_local *local,
 					rates |= BIT(j);
 			}
 		}
-		sta->sta.supp_rates[local->oper_channel->band] = rates;
+		sta->sta.supp_rates[band] = rates;
 	}
 
 	if (params->ht_capa)
@@ -1664,8 +1673,9 @@ static int ieee80211_join_mesh(struct wiphy *wiphy, struct net_device *dev,
 	if (err)
 		return err;
 
-	err = ieee80211_set_channel(wiphy, dev, setup->channel,
-				    setup->channel_type);
+	err = ieee80211_vif_use_channel(sdata, setup->channel,
+					setup->channel_type,
+					IEEE80211_CHANCTX_SHARED);
 	if (err)
 		return err;
 
@@ -1679,6 +1689,7 @@ static int ieee80211_leave_mesh(struct wiphy *wiphy, struct net_device *dev)
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
 	ieee80211_stop_mesh(sdata);
+	ieee80211_vif_release_channel(sdata);
 
 	return 0;
 }
@@ -1688,10 +1699,14 @@ static int ieee80211_change_bss(struct wiphy *wiphy,
 				struct net_device *dev,
 				struct bss_parameters *params)
 {
-	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	enum ieee80211_band band;
 	u32 changed = 0;
 
-	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	if (!rtnl_dereference(sdata->u.ap.beacon))
+		return -ENOENT;
+
+	band = ieee80211_get_sdata_band(sdata);
 
 	if (params->use_cts_prot >= 0) {
 		sdata->vif.bss_conf.use_cts_prot = params->use_cts_prot;
@@ -1704,7 +1719,7 @@ static int ieee80211_change_bss(struct wiphy *wiphy,
 	}
 
 	if (!sdata->vif.bss_conf.use_short_slot &&
-	    sdata->local->oper_channel->band == IEEE80211_BAND_5GHZ) {
+	    band == IEEE80211_BAND_5GHZ) {
 		sdata->vif.bss_conf.use_short_slot = true;
 		changed |= BSS_CHANGED_ERP_SLOT;
 	}
@@ -1718,9 +1733,7 @@ static int ieee80211_change_bss(struct wiphy *wiphy,
 	if (params->basic_rates) {
 		int i, j;
 		u32 rates = 0;
-		struct ieee80211_local *local = wiphy_priv(wiphy);
-		struct ieee80211_supported_band *sband =
-			wiphy->bands[local->oper_channel->band];
+		struct ieee80211_supported_band *sband = wiphy->bands[band];
 
 		for (i = 0; i < params->basic_rates_len; i++) {
 			int rate = (params->basic_rates[i] & 0x7f) * 5;
@@ -1872,20 +1885,6 @@ static int ieee80211_auth(struct wiphy *wiphy, struct net_device *dev,
 static int ieee80211_assoc(struct wiphy *wiphy, struct net_device *dev,
 			   struct cfg80211_assoc_request *req)
 {
-	struct ieee80211_local *local = wiphy_priv(wiphy);
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-
-	switch (ieee80211_get_channel_mode(local, sdata)) {
-	case CHAN_MODE_HOPPING:
-		return -EBUSY;
-	case CHAN_MODE_FIXED:
-		if (local->oper_channel == req->bss->channel)
-			break;
-		return -EBUSY;
-	case CHAN_MODE_UNDEFINED:
-		break;
-	}
-
 	return ieee80211_mgd_assoc(IEEE80211_DEV_TO_SUB_IF(dev), req);
 }
 
@@ -1904,30 +1903,12 @@ static int ieee80211_disassoc(struct wiphy *wiphy, struct net_device *dev,
 static int ieee80211_join_ibss(struct wiphy *wiphy, struct net_device *dev,
 			       struct cfg80211_ibss_params *params)
 {
-	struct ieee80211_local *local = wiphy_priv(wiphy);
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-
-	switch (ieee80211_get_channel_mode(local, sdata)) {
-	case CHAN_MODE_HOPPING:
-		return -EBUSY;
-	case CHAN_MODE_FIXED:
-		if (!params->channel_fixed)
-			return -EBUSY;
-		if (local->oper_channel == params->channel)
-			break;
-		return -EBUSY;
-	case CHAN_MODE_UNDEFINED:
-		break;
-	}
-
-	return ieee80211_ibss_join(sdata, params);
+	return ieee80211_ibss_join(IEEE80211_DEV_TO_SUB_IF(dev), params);
 }
 
 static int ieee80211_leave_ibss(struct wiphy *wiphy, struct net_device *dev)
 {
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-
-	return ieee80211_ibss_leave(sdata);
+	return ieee80211_ibss_leave(IEEE80211_DEV_TO_SUB_IF(dev));
 }
 
 static int ieee80211_set_wiphy_params(struct wiphy *wiphy, u32 changed)
@@ -1971,9 +1952,13 @@ static int ieee80211_set_tx_power(struct wiphy *wiphy,
 				  enum nl80211_tx_power_setting type, int mbm)
 {
 	struct ieee80211_local *local = wiphy_priv(wiphy);
-	struct ieee80211_channel *chan = local->oper_channel;
+	struct ieee80211_channel *chan = local->_oper_channel;
 	u32 changes = 0;
 
+	/* FIXME */
+	if (local->use_chanctx)
+		return -EOPNOTSUPP;
+
 	switch (type) {
 	case NL80211_TX_POWER_AUTOMATIC:
 		local->user_power_level = -1;
@@ -2518,10 +2503,20 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
 
 	/* Check if the operating channel is the requested channel */
 	if (!need_offchan) {
-		need_offchan = chan != local->oper_channel;
-		if (channel_type_valid &&
-		    channel_type != local->_oper_channel_type)
+		struct ieee80211_chanctx_conf *chanctx_conf;
+
+		rcu_read_lock();
+		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+
+		if (chanctx_conf) {
+			need_offchan = chan != chanctx_conf->channel;
+			if (channel_type_valid &&
+			    channel_type != chanctx_conf->channel_type)
+				need_offchan = true;
+		} else {
 			need_offchan = true;
+		}
+		rcu_read_unlock();
 	}
 
 	if (need_offchan && !offchan) {
@@ -2670,7 +2665,7 @@ static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata)
 	u16 capab;
 
 	capab = 0;
-	if (local->oper_channel->band != IEEE80211_BAND_2GHZ)
+	if (ieee80211_get_sdata_band(sdata) != IEEE80211_BAND_2GHZ)
 		return capab;
 
 	if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
@@ -2702,7 +2697,7 @@ ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 			       u16 status_code, struct sk_buff *skb)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct ieee80211_local *local = sdata->local;
+	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 	struct ieee80211_tdls_data *tf;
 
 	tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
@@ -2722,10 +2717,8 @@ ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 		tf->u.setup_req.capability =
 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
 
-		ieee80211_add_srates_ie(sdata, skb, false,
-					local->oper_channel->band);
-		ieee80211_add_ext_srates_ie(sdata, skb, false,
-					    local->oper_channel->band);
+		ieee80211_add_srates_ie(sdata, skb, false, band);
+		ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 		ieee80211_tdls_add_ext_capab(skb);
 		break;
 	case WLAN_TDLS_SETUP_RESPONSE:
@@ -2738,10 +2731,8 @@ ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 		tf->u.setup_resp.capability =
 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
 
-		ieee80211_add_srates_ie(sdata, skb, false,
-					local->oper_channel->band);
-		ieee80211_add_ext_srates_ie(sdata, skb, false,
-					    local->oper_channel->band);
+		ieee80211_add_srates_ie(sdata, skb, false, band);
+		ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 		ieee80211_tdls_add_ext_capab(skb);
 		break;
 	case WLAN_TDLS_SETUP_CONFIRM:
@@ -2779,7 +2770,7 @@ ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 			   u16 status_code, struct sk_buff *skb)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct ieee80211_local *local = sdata->local;
+	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 	struct ieee80211_mgmt *mgmt;
 
 	mgmt = (void *)skb_put(skb, 24);
@@ -2802,10 +2793,8 @@ ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 		mgmt->u.action.u.tdls_discover_resp.capability =
 			cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata));
 
-		ieee80211_add_srates_ie(sdata, skb, false,
-					local->oper_channel->band);
-		ieee80211_add_ext_srates_ie(sdata, skb, false,
-					    local->oper_channel->band);
+		ieee80211_add_srates_ie(sdata, skb, false, band);
+		ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 		ieee80211_tdls_add_ext_capab(skb);
 		break;
 	default:
@@ -2985,12 +2974,19 @@ static int ieee80211_probe_client(struct wiphy *wiphy, struct net_device *dev,
 	bool qos;
 	struct ieee80211_tx_info *info;
 	struct sta_info *sta;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	enum ieee80211_band band;
 
 	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON(!chanctx_conf)) {
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+	band = chanctx_conf->channel->band;
 	sta = sta_info_get(sdata, peer);
 	if (sta) {
 		qos = test_sta_flag(sta, WLAN_STA_WME);
-		rcu_read_unlock();
 	} else {
 		rcu_read_unlock();
 		return -ENOLINK;
@@ -3008,8 +3004,10 @@ static int ieee80211_probe_client(struct wiphy *wiphy, struct net_device *dev,
 	}
 
 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + size);
-	if (!skb)
+	if (!skb) {
+		rcu_read_unlock();
 		return -ENOMEM;
+	}
 
 	skb->dev = dev;
 
@@ -3034,8 +3032,9 @@ static int ieee80211_probe_client(struct wiphy *wiphy, struct net_device *dev,
 		nullfunc->qos_ctrl = cpu_to_le16(7);
 
 	local_bh_disable();
-	ieee80211_xmit(sdata, skb);
+	ieee80211_xmit(sdata, skb, band);
 	local_bh_enable();
+	rcu_read_unlock();
 
 	*cookie = (unsigned long) skb;
 	return 0;
@@ -3045,10 +3044,19 @@ static struct ieee80211_channel *
 ieee80211_cfg_get_channel(struct wiphy *wiphy, struct wireless_dev *wdev,
 			  enum nl80211_channel_type *type)
 {
-	struct ieee80211_local *local = wiphy_priv(wiphy);
+	struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *chan = NULL;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (chanctx_conf) {
+		*type = chanctx_conf->channel_type;
+		chan = chanctx_conf->channel;
+	}
+	rcu_read_unlock();
 
-	*type = local->_oper_channel_type;
-	return local->oper_channel;
+	return chan;
 }
 
 #ifdef CONFIG_PM
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 1a8dee42e546..41e1aa69f7aa 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -7,106 +7,6 @@
 #include "ieee80211_i.h"
 #include "driver-ops.h"
 
-static enum ieee80211_chan_mode
-__ieee80211_get_channel_mode(struct ieee80211_local *local,
-			     struct ieee80211_sub_if_data *ignore)
-{
-	struct ieee80211_sub_if_data *sdata;
-
-	lockdep_assert_held(&local->iflist_mtx);
-
-	list_for_each_entry(sdata, &local->interfaces, list) {
-		if (sdata == ignore)
-			continue;
-
-		if (!ieee80211_sdata_running(sdata))
-			continue;
-
-		switch (sdata->vif.type) {
-		case NL80211_IFTYPE_MONITOR:
-			continue;
-		case NL80211_IFTYPE_STATION:
-			if (!sdata->u.mgd.associated)
-				continue;
-			break;
-		case NL80211_IFTYPE_ADHOC:
-			if (!sdata->u.ibss.ssid_len)
-				continue;
-			if (!sdata->u.ibss.fixed_channel)
-				return CHAN_MODE_HOPPING;
-			break;
-		case NL80211_IFTYPE_AP_VLAN:
-			/* will also have _AP interface */
-			continue;
-		case NL80211_IFTYPE_AP:
-			if (!sdata->u.ap.beacon)
-				continue;
-			break;
-		case NL80211_IFTYPE_MESH_POINT:
-			if (!sdata->wdev.mesh_id_len)
-				continue;
-			break;
-		default:
-			break;
-		}
-
-		return CHAN_MODE_FIXED;
-	}
-
-	return CHAN_MODE_UNDEFINED;
-}
-
-enum ieee80211_chan_mode
-ieee80211_get_channel_mode(struct ieee80211_local *local,
-			   struct ieee80211_sub_if_data *ignore)
-{
-	enum ieee80211_chan_mode mode;
-
-	mutex_lock(&local->iflist_mtx);
-	mode = __ieee80211_get_channel_mode(local, ignore);
-	mutex_unlock(&local->iflist_mtx);
-
-	return mode;
-}
-
-static enum nl80211_channel_type
-ieee80211_get_superchan(struct ieee80211_local *local,
-			struct ieee80211_sub_if_data *sdata)
-{
-	enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT;
-	struct ieee80211_sub_if_data *tmp;
-
-	mutex_lock(&local->iflist_mtx);
-	list_for_each_entry(tmp, &local->interfaces, list) {
-		if (tmp == sdata)
-			continue;
-
-		if (!ieee80211_sdata_running(tmp))
-			continue;
-
-		switch (tmp->vif.bss_conf.channel_type) {
-		case NL80211_CHAN_NO_HT:
-		case NL80211_CHAN_HT20:
-			if (superchan > tmp->vif.bss_conf.channel_type)
-				break;
-
-			superchan = tmp->vif.bss_conf.channel_type;
-			break;
-		case NL80211_CHAN_HT40PLUS:
-			WARN_ON(superchan == NL80211_CHAN_HT40MINUS);
-			superchan = NL80211_CHAN_HT40PLUS;
-			break;
-		case NL80211_CHAN_HT40MINUS:
-			WARN_ON(superchan == NL80211_CHAN_HT40PLUS);
-			superchan = NL80211_CHAN_HT40MINUS;
-			break;
-		}
-	}
-	mutex_unlock(&local->iflist_mtx);
-
-	return superchan;
-}
-
 static bool
 ieee80211_channel_types_are_compatible(enum nl80211_channel_type chantype1,
 				       enum nl80211_channel_type chantype2,
@@ -149,26 +49,6 @@ ieee80211_channel_types_are_compatible(enum nl80211_channel_type chantype1,
 	return true;
 }
 
-bool ieee80211_set_channel_type(struct ieee80211_local *local,
-				struct ieee80211_sub_if_data *sdata,
-				enum nl80211_channel_type chantype)
-{
-	enum nl80211_channel_type superchan;
-	enum nl80211_channel_type compatchan;
-
-	superchan = ieee80211_get_superchan(local, sdata);
-	if (!ieee80211_channel_types_are_compatible(superchan, chantype,
-						    &compatchan))
-		return false;
-
-	local->_oper_channel_type = compatchan;
-
-	if (sdata)
-		sdata->vif.bss_conf.channel_type = chantype;
-
-	return true;
-}
-
 static void ieee80211_change_chantype(struct ieee80211_local *local,
 				      struct ieee80211_chanctx *ctx,
 				      enum nl80211_channel_type chantype)
@@ -178,6 +58,11 @@ static void ieee80211_change_chantype(struct ieee80211_local *local,
 
 	ctx->conf.channel_type = chantype;
 	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_CHANNEL_TYPE);
+
+	if (!local->use_chanctx) {
+		local->_oper_channel_type = chantype;
+		ieee80211_hw_config(local, 0);
+	}
 }
 
 static struct ieee80211_chanctx *
@@ -235,10 +120,16 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
 	ctx->conf.channel_type = channel_type;
 	ctx->mode = mode;
 
-	err = drv_add_chanctx(local, ctx);
-	if (err) {
-		kfree(ctx);
-		return ERR_PTR(err);
+	if (!local->use_chanctx) {
+		local->_oper_channel_type = channel_type;
+		local->_oper_channel = channel;
+		ieee80211_hw_config(local, 0);
+	} else {
+		err = drv_add_chanctx(local, ctx);
+		if (err) {
+			kfree(ctx);
+			return ERR_PTR(err);
+		}
 	}
 
 	list_add(&ctx->list, &local->chanctx_list);
@@ -253,7 +144,12 @@ static void ieee80211_free_chanctx(struct ieee80211_local *local,
 
 	WARN_ON_ONCE(ctx->refcount != 0);
 
-	drv_remove_chanctx(local, ctx);
+	if (!local->use_chanctx) {
+		local->_oper_channel_type = NL80211_CHAN_NO_HT;
+		ieee80211_hw_config(local, 0);
+	} else {
+		drv_remove_chanctx(local, ctx);
+	}
 
 	list_del(&ctx->list);
 	kfree_rcu(ctx, rcu_head);
@@ -359,6 +255,8 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_chanctx *ctx;
 	int ret;
 
+	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
+
 	mutex_lock(&local->chanctx_mtx);
 	__ieee80211_vif_release_channel(sdata);
 
@@ -370,6 +268,8 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
 		goto out;
 	}
 
+	sdata->vif.bss_conf.channel_type = channel_type;
+
 	ret = ieee80211_assign_vif_chanctx(sdata, ctx);
 	if (ret) {
 		/* if assign fails refcount stays the same */
@@ -385,6 +285,8 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
 
 void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
 {
+	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
+
 	mutex_lock(&sdata->local->chanctx_mtx);
 	__ieee80211_vif_release_channel(sdata);
 	mutex_unlock(&sdata->local->chanctx_mtx);
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 5f3620f0bc0a..34d9235117d9 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -26,7 +26,6 @@
 #include "rate.h"
 
 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
-#define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
 
 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
@@ -76,21 +75,22 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
 	}
 
-	memcpy(ifibss->bssid, bssid, ETH_ALEN);
-
 	sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
 
-	local->oper_channel = chan;
 	channel_type = ifibss->channel_type;
 	if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
 		channel_type = NL80211_CHAN_HT20;
-	if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
-		/* can only fail due to HT40+/- mismatch */
-		channel_type = NL80211_CHAN_HT20;
-		WARN_ON(!ieee80211_set_channel_type(local, sdata,
-						    NL80211_CHAN_HT20));
+
+	ieee80211_vif_release_channel(sdata);
+	if (ieee80211_vif_use_channel(sdata, chan, channel_type,
+				      ifibss->fixed_channel ?
+					IEEE80211_CHANCTX_SHARED :
+					IEEE80211_CHANCTX_EXCLUSIVE)) {
+		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
+		return;
 	}
-	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+
+	memcpy(ifibss->bssid, bssid, ETH_ALEN);
 
 	sband = local->hw.wiphy->bands[chan->band];
 
@@ -294,7 +294,8 @@ ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct ieee80211_local *local = sdata->local;
 	struct sta_info *sta;
-	int band = local->oper_channel->band;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	int band;
 
 	/*
 	 * XXX: Consider removing the least recently used entry and
@@ -317,6 +318,13 @@ ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
 		return NULL;
 	}
 
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON_ONCE(!chanctx_conf))
+		return NULL;
+	band = chanctx_conf->channel->band;
+	rcu_read_unlock();
+
 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
 	if (!sta) {
 		rcu_read_lock();
@@ -517,7 +525,8 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 		goto put_bss;
 
 	/* different channel */
-	if (cbss->channel != local->oper_channel)
+	if (sdata->u.ibss.fixed_channel &&
+	    sdata->u.ibss.channel != cbss->channel)
 		goto put_bss;
 
 	/* different SSID */
@@ -592,7 +601,8 @@ void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	struct ieee80211_local *local = sdata->local;
 	struct sta_info *sta;
-	int band = local->oper_channel->band;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	int band;
 
 	/*
 	 * XXX: Consider removing the least recently used entry and
@@ -610,6 +620,15 @@ void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
 		return;
 
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON_ONCE(!chanctx_conf)) {
+		rcu_read_unlock();
+		return;
+	}
+	band = chanctx_conf->channel->band;
+	rcu_read_unlock();
+
 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
 	if (!sta)
 		return;
@@ -784,18 +803,8 @@ static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
 		int interval = IEEE80211_SCAN_INTERVAL;
 
 		if (time_after(jiffies, ifibss->ibss_join_req +
-			       IEEE80211_IBSS_JOIN_TIMEOUT)) {
-			if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
-				ieee80211_sta_create_ibss(sdata);
-				return;
-			}
-			sdata_info(sdata, "IBSS not allowed on %d MHz\n",
-				   local->oper_channel->center_freq);
-
-			/* No IBSS found - decrease scan interval and continue
-			 * scanning. */
-			interval = IEEE80211_SCAN_INTERVAL_SLOW;
-		}
+			       IEEE80211_IBSS_JOIN_TIMEOUT))
+			ieee80211_sta_create_ibss(sdata);
 
 		mod_timer(&ifibss->timer,
 			  round_jiffies(jiffies + interval));
@@ -1086,17 +1095,6 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 	sdata->u.ibss.channel_type = params->channel_type;
 	sdata->u.ibss.fixed_channel = params->channel_fixed;
 
-	/* fix ourselves to that channel now already */
-	if (params->channel_fixed) {
-		sdata->local->oper_channel = params->channel;
-		if (!ieee80211_set_channel_type(sdata->local, sdata,
-					       params->channel_type)) {
-			mutex_unlock(&sdata->u.ibss.mtx);
-			kfree_skb(skb);
-			return -EINVAL;
-		}
-	}
-
 	if (params->ie) {
 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
 					   GFP_KERNEL);
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8fa00adcb8c0..6660118b46b3 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -773,6 +773,21 @@ struct ieee80211_sub_if_data *vif_to_sdata(struct ieee80211_vif *p)
 	return container_of(p, struct ieee80211_sub_if_data, vif);
 }
 
+static inline enum ieee80211_band
+ieee80211_get_sdata_band(struct ieee80211_sub_if_data *sdata)
+{
+	enum ieee80211_band band = IEEE80211_BAND_2GHZ;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (!WARN_ON(!chanctx_conf))
+		band = chanctx_conf->channel->band;
+	rcu_read_unlock();
+
+	return band;
+}
+
 enum sdata_queue_type {
 	IEEE80211_SDATA_QUEUE_TYPE_FRAME	= 0,
 	IEEE80211_SDATA_QUEUE_AGG_START		= 1,
@@ -1006,8 +1021,10 @@ struct ieee80211_local {
 	enum mac80211_scan_state next_scan_state;
 	struct delayed_work scan_work;
 	struct ieee80211_sub_if_data __rcu *scan_sdata;
+	struct ieee80211_channel *csa_channel;
+	/* For backward compatibility only -- do not use */
+	struct ieee80211_channel *_oper_channel;
 	enum nl80211_channel_type _oper_channel_type;
-	struct ieee80211_channel *oper_channel, *csa_channel;
 
 	/* Temporary remain-on-channel for off-channel operations */
 	struct ieee80211_channel *tmp_channel;
@@ -1121,6 +1138,8 @@ struct ieee80211_local {
 
 	/* virtual monitor interface */
 	struct ieee80211_sub_if_data __rcu *monitor_sdata;
+	struct ieee80211_channel *monitor_channel;
+	enum nl80211_channel_type monitor_channel_type;
 };
 
 static inline struct ieee80211_sub_if_data *
@@ -1423,11 +1442,42 @@ void mac80211_ev_michael_mic_failure(struct ieee80211_sub_if_data *sdata, int ke
 				     gfp_t gfp);
 void ieee80211_set_wmm_default(struct ieee80211_sub_if_data *sdata,
 			       bool bss_notify);
-void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb);
+void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
+		    enum ieee80211_band band);
+
+void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
+				 struct sk_buff *skb, int tid,
+				 enum ieee80211_band band);
+
+static inline void
+ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
+			  struct sk_buff *skb, int tid,
+			  enum ieee80211_band band)
+{
+	rcu_read_lock();
+	__ieee80211_tx_skb_tid_band(sdata, skb, tid, band);
+	rcu_read_unlock();
+}
 
-void ieee80211_tx_skb_tid(struct ieee80211_sub_if_data *sdata,
-			  struct sk_buff *skb, int tid);
-static void inline ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata,
+static inline void ieee80211_tx_skb_tid(struct ieee80211_sub_if_data *sdata,
+					struct sk_buff *skb, int tid)
+{
+	struct ieee80211_chanctx_conf *chanctx_conf;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON(!chanctx_conf)) {
+		rcu_read_unlock();
+		kfree_skb(skb);
+		return;
+	}
+
+	__ieee80211_tx_skb_tid_band(sdata, skb, tid,
+				    chanctx_conf->channel->band);
+	rcu_read_unlock();
+}
+
+static inline void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata,
 				    struct sk_buff *skb)
 {
 	/* Send all internal mgmt frames on VO. Accordingly set TID to 7. */
@@ -1494,7 +1544,7 @@ void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
 			      const u8 *ssid, size_t ssid_len,
 			      const u8 *ie, size_t ie_len,
 			      u32 ratemask, bool directed, bool no_cck,
-			      struct ieee80211_channel *channel);
+			      struct ieee80211_channel *channel, bool scan);
 
 void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata,
 				  const size_t supp_rates_len,
@@ -1525,18 +1575,6 @@ int ieee80211_add_ext_srates_ie(struct ieee80211_sub_if_data *sdata,
 				enum ieee80211_band band);
 
 /* channel management */
-enum ieee80211_chan_mode {
-	CHAN_MODE_UNDEFINED,
-	CHAN_MODE_HOPPING,
-	CHAN_MODE_FIXED,
-};
-
-enum ieee80211_chan_mode
-ieee80211_get_channel_mode(struct ieee80211_local *local,
-			   struct ieee80211_sub_if_data *ignore);
-bool ieee80211_set_channel_type(struct ieee80211_local *local,
-				struct ieee80211_sub_if_data *sdata,
-				enum nl80211_channel_type chantype);
 enum nl80211_channel_type
 ieee80211_ht_oper_to_channel_type(struct ieee80211_ht_operation *ht_oper);
 
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 6f8a73c64fb3..7cb8382b19e5 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -380,6 +380,15 @@ static int ieee80211_add_virtual_monitor(struct ieee80211_local *local)
 		goto out_unlock;
 	}
 
+	ret = ieee80211_vif_use_channel(sdata, local->monitor_channel,
+					local->monitor_channel_type,
+					IEEE80211_CHANCTX_EXCLUSIVE);
+	if (ret) {
+		drv_remove_interface(local, sdata);
+		kfree(sdata);
+		goto out