From: Aditya Kumar Singh <quic_adisi@quicinc.com>
Date: Fri, 6 Sep 2024 12:14:24 +0530
Subject: [PATCH] wifi: mac80211: handle DFS per link

In order to support DFS with MLO, handle the link ID now passed from
cfg80211, adjust the code to do everything per link and call the
notifications to cfg80211 correctly.

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://patch.msgid.link/20240906064426.2101315-7-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---

--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3464,6 +3464,7 @@ static int ieee80211_start_radar_detecti
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_chan_req chanreq = { .oper = *chandef };
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_link_data *link_data;
 	int err;
 
 	lockdep_assert_wiphy(local->hw.wiphy);
@@ -3471,16 +3472,20 @@ static int ieee80211_start_radar_detecti
 	if (!list_empty(&local->roc_list) || local->scanning)
 		return -EBUSY;
 
+	link_data = sdata_dereference(sdata->link[link_id], sdata);
+	if (!link_data)
+		return -ENOLINK;
+
 	/* whatever, but channel contexts should not complain about that one */
-	sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
-	sdata->deflink.needed_rx_chains = local->rx_chains;
+	link_data->smps_mode = IEEE80211_SMPS_OFF;
+	link_data->needed_rx_chains = local->rx_chains;
 
-	err = ieee80211_link_use_channel(&sdata->deflink, &chanreq,
+	err = ieee80211_link_use_channel(link_data, &chanreq,
 					 IEEE80211_CHANCTX_SHARED);
 	if (err)
 		return err;
 
-	wiphy_delayed_work_queue(wiphy, &sdata->deflink.dfs_cac_timer_work,
+	wiphy_delayed_work_queue(wiphy, &link_data->dfs_cac_timer_work,
 				 msecs_to_jiffies(cac_time_ms));
 
 	return 0;
@@ -3491,16 +3496,21 @@ static void ieee80211_end_cac(struct wip
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_link_data *link_data;
 
 	lockdep_assert_wiphy(local->hw.wiphy);
 
 	list_for_each_entry(sdata, &local->interfaces, list) {
+		link_data = sdata_dereference(sdata->link[link_id], sdata);
+		if (!link_data)
+			continue;
+
 		wiphy_delayed_work_cancel(wiphy,
-					  &sdata->deflink.dfs_cac_timer_work);
+					  &link_data->dfs_cac_timer_work);
 
-		if (sdata->wdev.links[0].cac_started) {
-			ieee80211_link_release_channel(&sdata->deflink);
-			sdata->wdev.links[0].cac_started = false;
+		if (sdata->wdev.links[link_id].cac_started) {
+			ieee80211_link_release_channel(link_data);
+			sdata->wdev.links[link_id].cac_started = false;
 		}
 	}
 }
--- a/net/mac80211/link.c
+++ b/net/mac80211/link.c
@@ -77,6 +77,16 @@ void ieee80211_link_stop(struct ieee8021
 			  &link->color_change_finalize_work);
 	wiphy_work_cancel(link->sdata->local->hw.wiphy,
 			  &link->csa.finalize_work);
+
+	if (link->sdata->wdev.links[link->link_id].cac_started) {
+		wiphy_delayed_work_cancel(link->sdata->local->hw.wiphy,
+					  &link->dfs_cac_timer_work);
+		cfg80211_cac_event(link->sdata->dev,
+				   &link->conf->chanreq.oper,
+				   NL80211_RADAR_CAC_ABORTED,
+				   GFP_KERNEL, link->link_id);
+	}
+
 	ieee80211_link_release_channel(link);
 }
 
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -3455,20 +3455,30 @@ void ieee80211_dfs_cac_cancel(struct iee
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct cfg80211_chan_def chandef;
+	struct ieee80211_link_data *link;
+	unsigned int link_id;
 
 	lockdep_assert_wiphy(local->hw.wiphy);
 
 	list_for_each_entry(sdata, &local->interfaces, list) {
-		wiphy_delayed_work_cancel(local->hw.wiphy,
-					  &sdata->deflink.dfs_cac_timer_work);
+		for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS;
+		     link_id++) {
+			link = sdata_dereference(sdata->link[link_id],
+						 sdata);
+			if (!link)
+				continue;
 
-		if (sdata->wdev.links[0].cac_started) {
-			chandef = sdata->vif.bss_conf.chanreq.oper;
-			ieee80211_link_release_channel(&sdata->deflink);
-			cfg80211_cac_event(sdata->dev,
-					   &chandef,
+			wiphy_delayed_work_cancel(local->hw.wiphy,
+						  &link->dfs_cac_timer_work);
+
+			if (!sdata->wdev.links[link_id].cac_started)
+				continue;
+
+			chandef = link->conf->chanreq.oper;
+			ieee80211_link_release_channel(link);
+			cfg80211_cac_event(sdata->dev, &chandef,
 					   NL80211_RADAR_CAC_ABORTED,
-					   GFP_KERNEL, 0);
+					   GFP_KERNEL, link_id);
 		}
 	}
 }