1 files changed, 174 insertions, 34 deletions

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 03ba6b5c537..f43613a97dd 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -9,6 +9,140 @@
 #include "ieee80211_i.h"
 #include "driver-ops.h"
 
+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);
+	}
+	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);
+}
+
 static void ieee80211_change_chanctx(struct ieee80211_local *local,
 				     struct ieee80211_chanctx *ctx,
 				     const struct cfg80211_chan_def *chandef)
@@ -20,6 +154,7 @@ static void ieee80211_change_chanctx(struct ieee80211_local *local,
 
 	ctx->conf.def = *chandef;
 	drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
+	ieee80211_recalc_chanctx_min_def(local, ctx);
 
 	if (!local->use_chanctx) {
 		local->_oper_chandef = *chandef;
@@ -93,11 +228,12 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
 	ctx->conf.rx_chains_dynamic = 1;
 	ctx->mode = mode;
 	ctx->conf.radar_enabled = ieee80211_is_radar_required(local);
+	ieee80211_recalc_chanctx_min_def(local, ctx);
 	if (!local->use_chanctx)
 		local->hw.conf.radar_enabled = ctx->conf.radar_enabled;
 
-	/* acquire mutex to prevent idle from changing */
-	mutex_lock(&local->mtx);
+	/* we hold the mutex to prevent idle from changing */
+	lockdep_assert_held(&local->mtx);
 	/* turn idle off *before* setting channel -- some drivers need that */
 	changed = ieee80211_idle_off(local);
 	if (changed)
@@ -110,19 +246,14 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
 		err = drv_add_chanctx(local, ctx);
 		if (err) {
 			kfree(ctx);
-			ctx = ERR_PTR(err);
-
 			ieee80211_recalc_idle(local);
-			goto out;
+			return ERR_PTR(err);
 		}
 	}
 
 	/* and keep the mutex held until the new chanctx is on the list */
 	list_add_rcu(&ctx->list, &local->chanctx_list);
 
- out:
-	mutex_unlock(&local->mtx);
-
 	return ctx;
 }
 
@@ -158,9 +289,7 @@ static void ieee80211_free_chanctx(struct ieee80211_local *local,
 	/* throw a warning if this wasn't the only channel context. */
 	WARN_ON(check_single_channel && !list_empty(&local->chanctx_list));
 
-	mutex_lock(&local->mtx);
 	ieee80211_recalc_idle(local);
-	mutex_unlock(&local->mtx);
 }
 
 static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
@@ -179,6 +308,7 @@ static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 	ctx->refcount++;
 
 	ieee80211_recalc_txpower(sdata);
+	ieee80211_recalc_chanctx_min_def(local, ctx);
 	sdata->vif.bss_conf.idle = false;
 
 	if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE &&
@@ -221,6 +351,31 @@ static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 	ieee80211_change_chanctx(local, ctx, compat);
 }
 
+static void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
+					   struct ieee80211_chanctx *chanctx)
+{
+	bool radar_enabled;
+
+	lockdep_assert_held(&local->chanctx_mtx);
+	/* for setting local->radar_detect_enabled */
+	lockdep_assert_held(&local->mtx);
+
+	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);
+}
+
 static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 					   struct ieee80211_chanctx *ctx)
 {
@@ -243,6 +398,7 @@ static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
 		ieee80211_recalc_chanctx_chantype(sdata->local, ctx);
 		ieee80211_recalc_smps_chanctx(local, ctx);
 		ieee80211_recalc_radar_chanctx(local, ctx);
+		ieee80211_recalc_chanctx_min_def(local, ctx);
 	}
 }
 
@@ -266,29 +422,6 @@ static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
 		ieee80211_free_chanctx(local, ctx);
 }
 
-void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local,
-				    struct ieee80211_chanctx *chanctx)
-{
-	bool radar_enabled;
-
-	lockdep_assert_held(&local->chanctx_mtx);
-
-	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);
-}
-
 void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
 				   struct ieee80211_chanctx *chanctx)
 {
@@ -380,6 +513,8 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_chanctx *ctx;
 	int ret;
 
+	lockdep_assert_held(&local->mtx);
+
 	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
 
 	mutex_lock(&local->chanctx_mtx);
@@ -411,15 +546,17 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
 }
 
 int ieee80211_vif_change_channel(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;
+	const struct cfg80211_chan_def *chandef = &sdata->csa_chandef;
 	int ret;
 	u32 chanctx_changed = 0;
 
+	lockdep_assert_held(&local->mtx);
+
 	/* should never be called if not performing a channel switch. */
 	if (WARN_ON(!sdata->vif.csa_active))
 		return -EINVAL;
@@ -456,6 +593,7 @@ int ieee80211_vif_change_channel(struct ieee80211_sub_if_data *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);
 
 	ret = 0;
  out:
@@ -516,6 +654,8 @@ void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
 {
 	WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
 
+	lockdep_assert_held(&sdata->local->mtx);
+
 	mutex_lock(&sdata->local->chanctx_mtx);
 	__ieee80211_vif_release_channel(sdata);
 	mutex_unlock(&sdata->local->chanctx_mtx);