wifi: cfg80211: handle DFS per link

Currently, during starting a radar detection, no link id information is
parsed and passed down. In order to support starting radar detection
during Multi Link Operation, it is required to pass link id as well.

Add changes to first parse and then pass link id in the start radar
detection path.

Additionally, update notification APIs to allow drivers/mac80211 to
pass the link ID.

However, everything is handled at link 0 only until all API's are ready to
handle it per link.

Signed-off-by: Aditya Kumar Singh <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Johannes Berg <[e-mail]>

drivers/net/wireless/marvell/mwifiex/11h.c

···
 			    "CAC timer finished; No radar detected\n");
 		cfg80211_cac_event(priv->netdev, &chandef,
 				   NL80211_RADAR_CAC_FINISHED,
-				   GFP_KERNEL);
+				   GFP_KERNEL, 0);
 	}
 }
 
···
 			    "Aborting delayed work for CAC.\n");
 		cancel_delayed_work_sync(&priv->dfs_cac_work);
 		cfg80211_cac_event(priv->netdev, &priv->dfs_chandef,
-				   NL80211_RADAR_CAC_ABORTED, GFP_KERNEL);
+				   NL80211_RADAR_CAC_ABORTED, GFP_KERNEL,
+				   0);
 	}
 }
 
···
 				cfg80211_cac_event(priv->netdev,
 						   &priv->dfs_chandef,
 						   NL80211_RADAR_DETECTED,
-						   GFP_KERNEL);
+						   GFP_KERNEL, 0);
 			}
 			break;
 		default:

drivers/net/wireless/marvell/mwifiex/cfg80211.c

···
 mwifiex_cfg80211_start_radar_detection(struct wiphy *wiphy,
 				       struct net_device *dev,
 				       struct cfg80211_chan_def *chandef,
-				       u32 cac_time_ms)
+				       u32 cac_time_ms, int link_id)
 {
 	struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
 	struct mwifiex_radar_params radar_params;

drivers/net/wireless/quantenna/qtnfmac/cfg80211.c

···
 static int qtnf_start_radar_detection(struct wiphy *wiphy,
 				      struct net_device *ndev,
 				      struct cfg80211_chan_def *chandef,
-				      u32 cac_time_ms)
+				      u32 cac_time_ms, int link_id)
 {
 	struct qtnf_vif *vif = qtnf_netdev_get_priv(ndev);
 	int ret;

drivers/net/wireless/quantenna/qtnfmac/event.c

···
 			break;
 
 		cfg80211_cac_event(vif->netdev, &chandef,
-				   NL80211_RADAR_CAC_FINISHED, GFP_KERNEL);
+				   NL80211_RADAR_CAC_FINISHED, GFP_KERNEL, 0);
 		break;
 	case QLINK_RADAR_CAC_ABORTED:
 		if (!vif->wdev.links[0].cac_started)
 			break;
 
 		cfg80211_cac_event(vif->netdev, &chandef,
-				   NL80211_RADAR_CAC_ABORTED, GFP_KERNEL);
+				   NL80211_RADAR_CAC_ABORTED, GFP_KERNEL, 0);
 		break;
 	case QLINK_RADAR_CAC_STARTED:
 		if (vif->wdev.links[0].cac_started)
···
 			break;
 
 		cfg80211_cac_event(vif->netdev, &chandef,
-				   NL80211_RADAR_CAC_STARTED, GFP_KERNEL);
+				   NL80211_RADAR_CAC_STARTED, GFP_KERNEL, 0);
 		break;
 	default:
 		pr_warn("%s: unhandled radar event %u\n",

include/net/cfg80211.h

···
 	int	(*start_radar_detection)(struct wiphy *wiphy,
 					 struct net_device *dev,
 					 struct cfg80211_chan_def *chandef,
-					 u32 cac_time_ms);
+					 u32 cac_time_ms, int link_id);
 	void	(*end_cac)(struct wiphy *wiphy,
-				struct net_device *dev);
+			   struct net_device *dev, unsigned int link_id);
 	int	(*update_ft_ies)(struct wiphy *wiphy, struct net_device *dev,
 				 struct cfg80211_update_ft_ies_params *ftie);
 	int	(*crit_proto_start)(struct wiphy *wiphy,
···
  * @chandef: chandef for the current channel
  * @event: type of event
  * @gfp: context flags
+ * @link_id: valid link_id for MLO operation or 0 otherwise.
  *
  * This function is called when a Channel availability check (CAC) is finished
  * or aborted. This must be called to notify the completion of a CAC process,
···
  */
 void cfg80211_cac_event(struct net_device *netdev,
 			const struct cfg80211_chan_def *chandef,
-			enum nl80211_radar_event event, gfp_t gfp);
+			enum nl80211_radar_event event, gfp_t gfp,
+			unsigned int link_id);
 
 /**
  * cfg80211_background_cac_abort - Channel Availability Check offchan abort event

net/mac80211/cfg.c

···
 		wiphy_delayed_work_cancel(wiphy, &link->dfs_cac_timer_work);
 		cfg80211_cac_event(sdata->dev, &chandef,
 				   NL80211_RADAR_CAC_ABORTED,
-				   GFP_KERNEL);
+				   GFP_KERNEL, 0);
 	}
 
 	drv_stop_ap(sdata->local, sdata, link_conf);
···
 static int ieee80211_start_radar_detection(struct wiphy *wiphy,
 					   struct net_device *dev,
 					   struct cfg80211_chan_def *chandef,
-					   u32 cac_time_ms)
+					   u32 cac_time_ms, int link_id)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_chan_req chanreq = { .oper = *chandef };
···
 }
 
 static void ieee80211_end_cac(struct wiphy *wiphy,
-			      struct net_device *dev)
+			      struct net_device *dev, unsigned int link_id)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_local *local = sdata->local;

net/mac80211/iface.c

···
 		ieee80211_link_release_channel(&sdata->deflink);
 		cfg80211_cac_event(sdata->dev, &chandef,
 				   NL80211_RADAR_CAC_ABORTED,
-				   GFP_KERNEL);
+				   GFP_KERNEL, 0);
 	}
 
 	if (sdata->vif.type == NL80211_IFTYPE_AP) {

net/mac80211/mlme.c

···
 		ieee80211_link_release_channel(link);
 		cfg80211_cac_event(sdata->dev, &chandef,
 				   NL80211_RADAR_CAC_FINISHED,
-				   GFP_KERNEL);
+				   GFP_KERNEL, 0);
 	}
 }
 

net/mac80211/util.c

···
 			cfg80211_cac_event(sdata->dev,
 					   &chandef,
 					   NL80211_RADAR_CAC_ABORTED,
-					   GFP_KERNEL);
+					   GFP_KERNEL, 0);
 		}
 	}
 }

net/wireless/mlme.c

···
 
 void cfg80211_cac_event(struct net_device *netdev,
 			const struct cfg80211_chan_def *chandef,
-			enum nl80211_radar_event event, gfp_t gfp)
+			enum nl80211_radar_event event, gfp_t gfp,
+			unsigned int link_id)
 {
 	struct wireless_dev *wdev = netdev->ieee80211_ptr;
 	struct wiphy *wiphy = wdev->wiphy;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 	unsigned long timeout;
 
-	/* not yet supported */
-	if (wdev->valid_links)
+	if (WARN_ON(wdev->valid_links &&
+		    !(wdev->valid_links & BIT(link_id))))
 		return;
 
-	trace_cfg80211_cac_event(netdev, event);
+	trace_cfg80211_cac_event(netdev, event, link_id);
 
 	if (WARN_ON(!wdev->links[0].cac_started &&
 		    event != NL80211_RADAR_CAC_STARTED))

net/wireless/nl80211.c

···
 		goto unlock;
 	}
 
-	if (cfg80211_beaconing_iface_active(wdev) || wdev->links[0].cac_started) {
+	if (cfg80211_beaconing_iface_active(wdev)) {
+		/* During MLO other link(s) can beacon, only the current link
+		 * can not already beacon
+		 */
+		if (wdev->valid_links &&
+		    !wdev->links[0].ap.beacon_interval) {
+			/* nothing */
+		} else {
+			err = -EBUSY;
+			goto unlock;
+		}
+	}
+
+	if (wdev->links[0].cac_started) {
 		err = -EBUSY;
 		goto unlock;
 	}
···
 	if (WARN_ON(!cac_time_ms))
 		cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
 
-	err = rdev_start_radar_detection(rdev, dev, &chandef, cac_time_ms);
+	err = rdev_start_radar_detection(rdev, dev, &chandef, cac_time_ms,
+					 0);
 	if (!err) {
 		switch (wdev->iftype) {
 		case NL80211_IFTYPE_AP:
···
 	SELECTOR(__sel, NETDEV_UP_NOTMX,		\
 		 NL80211_FLAG_NEED_NETDEV_UP |		\
 		 NL80211_FLAG_NO_WIPHY_MTX)		\
-	SELECTOR(__sel, NETDEV_UP_NOTMX_NOMLO,		\
+	SELECTOR(__sel, NETDEV_UP_NOTMX_MLO,		\
 		 NL80211_FLAG_NEED_NETDEV_UP |		\
 		 NL80211_FLAG_NO_WIPHY_MTX |		\
-		 NL80211_FLAG_MLO_UNSUPPORTED)		\
+		 NL80211_FLAG_MLO_VALID_LINK_ID)	\
 	SELECTOR(__sel, NETDEV_UP_CLEAR,		\
 		 NL80211_FLAG_NEED_NETDEV_UP |		\
 		 NL80211_FLAG_CLEAR_SKB)		\
···
 		.flags = GENL_UNS_ADMIN_PERM,
 		.internal_flags = IFLAGS(NL80211_FLAG_NEED_NETDEV_UP |
 					 NL80211_FLAG_NO_WIPHY_MTX |
-					 NL80211_FLAG_MLO_UNSUPPORTED),
+					 NL80211_FLAG_MLO_VALID_LINK_ID),
 	},
 	{
 		.cmd = NL80211_CMD_GET_PROTOCOL_FEATURES,

net/wireless/rdev-ops.h

···
 rdev_start_radar_detection(struct cfg80211_registered_device *rdev,
 			   struct net_device *dev,
 			   struct cfg80211_chan_def *chandef,
-			   u32 cac_time_ms)
+			   u32 cac_time_ms, int link_id)
 {
 	int ret = -EOPNOTSUPP;
 
 	trace_rdev_start_radar_detection(&rdev->wiphy, dev, chandef,
-					 cac_time_ms);
+					 cac_time_ms, link_id);
 	if (rdev->ops->start_radar_detection)
 		ret = rdev->ops->start_radar_detection(&rdev->wiphy, dev,
-						       chandef, cac_time_ms);
+						       chandef, cac_time_ms,
+						       link_id);
 	trace_rdev_return_int(&rdev->wiphy, ret);
 	return ret;
 }
 
 static inline void
 rdev_end_cac(struct cfg80211_registered_device *rdev,
-	     struct net_device *dev)
+	     struct net_device *dev, unsigned int link_id)
 {
-	trace_rdev_end_cac(&rdev->wiphy, dev);
+	trace_rdev_end_cac(&rdev->wiphy, dev, link_id);
 	if (rdev->ops->end_cac)
-		rdev->ops->end_cac(&rdev->wiphy, dev);
+		rdev->ops->end_cac(&rdev->wiphy, dev, link_id);
 	trace_rdev_return_void(&rdev->wiphy);
 }
 

net/wireless/reg.c

···
 static void cfg80211_check_and_end_cac(struct cfg80211_registered_device *rdev)
 {
 	struct wireless_dev *wdev;
+	unsigned int link_id;
+
 	/* If we finished CAC or received radar, we should end any
 	 * CAC running on the same channels.
 	 * the check !cfg80211_chandef_dfs_usable contain 2 options:
···
 	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
 		struct cfg80211_chan_def *chandef;
 
-		if (!wdev->links[0].cac_started)
-			continue;
+		for_each_valid_link(wdev, link_id) {
+			if (!wdev->links[link_id].cac_started)
+				continue;
 
-		/* FIXME: radar detection is tied to link 0 for now */
-		chandef = wdev_chandef(wdev, 0);
-		if (!chandef)
-			continue;
+			chandef = wdev_chandef(wdev, link_id);
+			if (!chandef)
+				continue;
 
-		if (!cfg80211_chandef_dfs_usable(&rdev->wiphy, chandef))
-			rdev_end_cac(rdev, wdev->netdev);
+			if (!cfg80211_chandef_dfs_usable(&rdev->wiphy, chandef))
+				rdev_end_cac(rdev, wdev->netdev, link_id);
+		}
 	}
 }
 

net/wireless/trace.h

···
 );
 
 TRACE_EVENT(rdev_end_cac,
-	TP_PROTO(struct wiphy *wiphy, struct net_device *netdev),
-	TP_ARGS(wiphy, netdev),
+	TP_PROTO(struct wiphy *wiphy, struct net_device *netdev,
+		 unsigned int link_id),
+	TP_ARGS(wiphy, netdev, link_id),
 	TP_STRUCT__entry(
 		WIPHY_ENTRY
 		NETDEV_ENTRY
+		__field(unsigned int, link_id)
 	),
 	TP_fast_assign(
 		WIPHY_ASSIGN;
 		NETDEV_ASSIGN;
+		__entry->link_id = link_id;
 	),
-	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT, WIPHY_PR_ARG, NETDEV_PR_ARG)
+	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", link_id: %d",
+		  WIPHY_PR_ARG, NETDEV_PR_ARG, __entry->link_id)
 );
 
 DECLARE_EVENT_CLASS(station_add_change,
···
 TRACE_EVENT(rdev_start_radar_detection,
 	TP_PROTO(struct wiphy *wiphy, struct net_device *netdev,
 		 struct cfg80211_chan_def *chandef,
-		 u32 cac_time_ms),
-	TP_ARGS(wiphy, netdev, chandef, cac_time_ms),
+		 u32 cac_time_ms, int link_id),
+	TP_ARGS(wiphy, netdev, chandef, cac_time_ms, link_id),
 	TP_STRUCT__entry(
 		WIPHY_ENTRY
 		NETDEV_ENTRY
 		CHAN_DEF_ENTRY
 		__field(u32, cac_time_ms)
+		__field(int, link_id)
 	),
 	TP_fast_assign(
 		WIPHY_ASSIGN;
 		NETDEV_ASSIGN;
 		CHAN_DEF_ASSIGN(chandef);
 		__entry->cac_time_ms = cac_time_ms;
+		__entry->link_id = link_id;
 	),
 	TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", " CHAN_DEF_PR_FMT
-		  ", cac_time_ms=%u",
+		  ", cac_time_ms=%u, link_id=%d",
 		  WIPHY_PR_ARG, NETDEV_PR_ARG, CHAN_DEF_PR_ARG,
-		  __entry->cac_time_ms)
+		  __entry->cac_time_ms, __entry->link_id)
 );
 
 TRACE_EVENT(rdev_set_mcast_rate,
···
 );
 
 TRACE_EVENT(cfg80211_cac_event,
-	TP_PROTO(struct net_device *netdev, enum nl80211_radar_event evt),
-	TP_ARGS(netdev, evt),
+	TP_PROTO(struct net_device *netdev, enum nl80211_radar_event evt,
+		 unsigned int link_id),
+	TP_ARGS(netdev, evt, link_id),
 	TP_STRUCT__entry(
 		NETDEV_ENTRY
 		__field(enum nl80211_radar_event, evt)
+		__field(unsigned int, link_id)
 	),
 	TP_fast_assign(
 		NETDEV_ASSIGN;
 		__entry->evt = evt;
+		__entry->link_id = link_id;
 	),
-	TP_printk(NETDEV_PR_FMT ",  event: %d",
-		  NETDEV_PR_ARG, __entry->evt)
+	TP_printk(NETDEV_PR_FMT ",  event: %d, link_id=%u",
+		  NETDEV_PR_ARG, __entry->evt, __entry->link_id)
 );
 
 DECLARE_EVENT_CLASS(cfg80211_rx_evt,