wifi: mac80211: start and finalize channel switch on link basis

Add changes to start a channel switch as well as finalize it on link basis
in order to support CSA with MLO as well.
Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://msgid.link/20240130140918.1172387-5-quic_adisi@quicinc.comSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -3633,6 +3633,7 @@ static int __ieee80211_csa_finalize(struct ieee80211_link_data *link_data)
 {
 	struct ieee80211_sub_if_data *sdata = link_data->sdata;
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_bss_conf *link_conf = link_data->conf;
 	u64 changed = 0;
 	int err;
 
@@ -3654,16 +3655,16 @@ static int __ieee80211_csa_finalize(struct ieee80211_link_data *link_data)
 		if (link_data->reserved_ready)
 			return 0;
 
-		return ieee80211_link_use_reserved_context(&sdata->deflink);
+		return ieee80211_link_use_reserved_context(link_data);
 	}
 
-	if (!cfg80211_chandef_identical(&link_data->conf->chanreq.oper,
+	if (!cfg80211_chandef_identical(&link_conf->chanreq.oper,
 					&link_data->csa_chanreq.oper))
 		return -EINVAL;
 
-	sdata->vif.bss_conf.csa_active = false;
+	link_conf->csa_active = false;
 
-	err = ieee80211_set_after_csa_beacon(&sdata->deflink, &changed);
+	err = ieee80211_set_after_csa_beacon(link_data, &changed);
 	if (err)
 		return err;
 
@@ -3690,7 +3691,8 @@ static void ieee80211_csa_finalize(struct ieee80211_link_data *link_data)
 	struct ieee80211_sub_if_data *sdata = link_data->sdata;
 
 	if (__ieee80211_csa_finalize(link_data)) {
-		sdata_info(sdata, "failed to finalize CSA, disconnecting\n");
+		sdata_info(sdata, "failed to finalize CSA on link %d, disconnecting\n",
+			   link_data->link_id);
 		cfg80211_stop_iface(sdata->local->hw.wiphy, &sdata->wdev,
 				    GFP_KERNEL);
 	}
@@ -3867,7 +3869,10 @@ __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 	struct ieee80211_channel_switch ch_switch;
 	struct ieee80211_chanctx_conf *conf;
 	struct ieee80211_chanctx *chanctx;
+	struct ieee80211_bss_conf *link_conf;
+	struct ieee80211_link_data *link_data;
 	u64 changed = 0;
+	u8 link_id = params->link_id;
 	int err;
 
 	lockdep_assert_wiphy(local->hw.wiphy);
@@ -3878,15 +3883,23 @@ __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 	if (sdata->wdev.cac_started)
 		return -EBUSY;
 
-	if (chanreq.oper.punctured && !sdata->vif.bss_conf.eht_support)
+	if (WARN_ON(link_id >= IEEE80211_MLD_MAX_NUM_LINKS))
+		return -EINVAL;
+
+	link_data = wiphy_dereference(wiphy, sdata->link[link_id]);
+	if (!link_data)
+		return -ENOLINK;
+
+	link_conf = link_data->conf;
+
+	if (chanreq.oper.punctured && !link_conf->eht_support)
 		return -EINVAL;
 
 	/* don't allow another channel switch if one is already active. */
-	if (sdata->vif.bss_conf.csa_active)
+	if (link_conf->csa_active)
 		return -EBUSY;
 
-	conf = rcu_dereference_protected(sdata->vif.bss_conf.chanctx_conf,
-					 lockdep_is_held(&local->hw.wiphy->mtx));
+	conf = wiphy_dereference(wiphy, link_conf->chanctx_conf);
 	if (!conf) {
 		err = -EBUSY;
 		goto out;
@@ -3910,7 +3923,7 @@ __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 	if (err)
 		goto out;
 
-	err = ieee80211_link_reserve_chanctx(&sdata->deflink, &chanreq,
+	err = ieee80211_link_reserve_chanctx(link_data, &chanreq,
 					     chanctx->mode,
 					     params->radar_required);
 	if (err)
@@ -3919,40 +3932,38 @@ __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 	/* if reservation is invalid then this will fail */
 	err = ieee80211_check_combinations(sdata, NULL, chanctx->mode, 0);
 	if (err) {
-		ieee80211_link_unreserve_chanctx(&sdata->deflink);
+		ieee80211_link_unreserve_chanctx(link_data);
 		goto out;
 	}
 
 	/* if there is a color change in progress, abort it */
-	if (sdata->vif.bss_conf.color_change_active)
+	if (link_conf->color_change_active)
 		ieee80211_color_change_abort(sdata);
 
-	err = ieee80211_set_csa_beacon(&sdata->deflink, params, &changed);
+	err = ieee80211_set_csa_beacon(link_data, params, &changed);
 	if (err) {
-		ieee80211_link_unreserve_chanctx(&sdata->deflink);
+		ieee80211_link_unreserve_chanctx(link_data);
 		goto out;
 	}
 
-	sdata->deflink.csa_chanreq = chanreq; 
-	sdata->deflink.csa_block_tx = params->block_tx;
-	sdata->vif.bss_conf.csa_active = true;
+	link_data->csa_chanreq = chanreq; 
+	link_data->csa_block_tx = params->block_tx;
+	link_conf->csa_active = true;
 
-	if (sdata->deflink.csa_block_tx)
+	if (link_data->csa_block_tx)
 		ieee80211_stop_vif_queues(local, sdata,
 					  IEEE80211_QUEUE_STOP_REASON_CSA);
 
 	cfg80211_ch_switch_started_notify(sdata->dev,
-					  &sdata->deflink.csa_chanreq.oper, 0,
+					  &link_data->csa_chanreq.oper, 0,
 					  params->count, params->block_tx);
 
 	if (changed) {
-		ieee80211_link_info_change_notify(sdata, &sdata->deflink,
-						  changed);
-		drv_channel_switch_beacon(sdata,
-					  &sdata->deflink.csa_chanreq.oper);
+		ieee80211_link_info_change_notify(sdata, link_data, changed);
+		drv_channel_switch_beacon(sdata, &link_data->csa_chanreq.oper);
 	} else {
 		/* if the beacon didn't change, we can finalize immediately */
-		ieee80211_csa_finalize(&sdata->deflink);
+		ieee80211_csa_finalize(link_data);
 	}
 
 out:

net/mac80211/link.c

@@ -73,6 +73,8 @@ void ieee80211_link_stop(struct ieee80211_link_data *link)
 		ieee80211_mgd_stop_link(link);
 
 	cancel_delayed_work_sync(&link->color_collision_detect_work);
+	wiphy_work_cancel(link->sdata->local->hw.wiphy,
+			  &link->csa_finalize_work);
 	ieee80211_link_release_channel(link);
 }