cfg80211: rename offchannel_chain structs to background_chain to avoid confusion with ETSI standard

ETSI standard defines "Offchannel CAC" as:
"Off-Channel CAC is performed by a number of non-continuous checks
spread over a period in time. This period, which is required to
determine the presence of radar signals, is defined as the Off-Channel
CAC Time..
Minimum Off-Channel CAC Time 6 minutes and Maximum Off-Channel CAC Time
4 hours..".
mac80211 implementation refers to a dedicated hw chain used for continuous
radar monitoring. Rename offchannel_* references to background_* in
order to avoid confusion with ETSI standard.

Signed-off-by: Lorenzo Bianconi <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Johannes Berg <[e-mail]>

include/net/cfg80211.h

···
  *	those to decrypt (Re)Association Request and encrypt (Re)Association
  *	Response frame.
  *
- * @set_radar_offchan: Configure dedicated offchannel chain available for
+ * @set_radar_background: Configure dedicated offchannel chain available for
  *	radar/CAC detection on some hw. This chain can't be used to transmit
  *	or receive frames and it is bounded to a running wdev.
- *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ *	Background radar/CAC detection allows to avoid the CAC downtime
  *	switching to a different channel during CAC detection on the selected
  *	radar channel.
  *	The caller is expected to set chandef pointer to NULL in order to
- *	disable offchannel CAC/radar detection.
+ *	disable background CAC/radar detection.
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow);
···
 				struct cfg80211_color_change_settings *params);
 	int     (*set_fils_aad)(struct wiphy *wiphy, struct net_device *dev,
 				struct cfg80211_fils_aad *fils_aad);
-	int	(*set_radar_offchan)(struct wiphy *wiphy,
-				     struct cfg80211_chan_def *chandef);
+	int	(*set_radar_background)(struct wiphy *wiphy,
+					struct cfg80211_chan_def *chandef);
 };
 
 /*
···
 }
 
 static inline void
-cfg80211_offchan_radar_event(struct wiphy *wiphy,
-			     struct cfg80211_chan_def *chandef,
-			     gfp_t gfp)
+cfg80211_background_radar_event(struct wiphy *wiphy,
+				struct cfg80211_chan_def *chandef,
+				gfp_t gfp)
 {
 	__cfg80211_radar_event(wiphy, chandef, true, gfp);
 }
···
 			enum nl80211_radar_event event, gfp_t gfp);
 
 /**
- * cfg80211_offchan_cac_abort - Channel Availability Check offchan abort event
+ * cfg80211_background_cac_abort - Channel Availability Check offchan abort event
  * @wiphy: the wiphy
  *
  * This function is called by the driver when a Channel Availability Check
  * (CAC) is aborted by a offchannel dedicated chain.
  */
-void cfg80211_offchan_cac_abort(struct wiphy *wiphy);
+void cfg80211_background_cac_abort(struct wiphy *wiphy);
 
 /**
  * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying

include/net/mac80211.h

···
  *	twt structure.
  * @twt_teardown_request: Update the hw with TWT teardown request received
  *	from the peer.
- * @set_radar_offchan: Configure dedicated offchannel chain available for
+ * @set_radar_background: Configure dedicated offchannel chain available for
  *	radar/CAC detection on some hw. This chain can't be used to transmit
  *	or receive frames and it is bounded to a running wdev.
- *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ *	Background radar/CAC detection allows to avoid the CAC downtime
  *	switching to a different channel during CAC detection on the selected
  *	radar channel.
  *	The caller is expected to set chandef pointer to NULL in order to
- *	disable offchannel CAC/radar detection.
+ *	disable background CAC/radar detection.
  * @net_fill_forward_path: Called from .ndo_fill_forward_path in order to
  *	resolve a path for hardware flow offloading
  */
···
 			      struct ieee80211_twt_setup *twt);
 	void (*twt_teardown_request)(struct ieee80211_hw *hw,
 				     struct ieee80211_sta *sta, u8 flowid);
-	int (*set_radar_offchan)(struct ieee80211_hw *hw,
-				 struct cfg80211_chan_def *chandef);
+	int (*set_radar_background)(struct ieee80211_hw *hw,
+				    struct cfg80211_chan_def *chandef);
 	int (*net_fill_forward_path)(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif,
 				     struct ieee80211_sta *sta,

include/uapi/linux/nl80211.h

···
  *	Mandatory parameter for the transmitting interface to enable MBSSID.
  *	Optional for the non-transmitting interfaces.
  *
- * @NL80211_ATTR_RADAR_OFFCHAN: Configure dedicated offchannel chain available for
- *	radar/CAC detection on some hw. This chain can't be used to transmit
- *	or receive frames and it is bounded to a running wdev.
- *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ * @NL80211_ATTR_RADAR_BACKGROUND: Configure dedicated offchannel chain
+ *	available for radar/CAC detection on some hw. This chain can't be used
+ *	to transmit or receive frames and it is bounded to a running wdev.
+ *	Background radar/CAC detection allows to avoid the CAC downtime
  *	switching on a different channel during CAC detection on the selected
  *	radar channel.
  *
···
 	NL80211_ATTR_MBSSID_CONFIG,
 	NL80211_ATTR_MBSSID_ELEMS,
 
-	NL80211_ATTR_RADAR_OFFCHAN,
+	NL80211_ATTR_RADAR_BACKGROUND,
 
 	/* add attributes here, update the policy in nl80211.c */
 
···
  *	frames. Userspace has to share FILS AAD details to the driver by using
  *	@NL80211_CMD_SET_FILS_AAD.
  *
- * @NL80211_EXT_FEATURE_RADAR_OFFCHAN: Device supports offchannel radar/CAC
+ * @NL80211_EXT_FEATURE_RADAR_BACKGROUND: Device supports background radar/CAC
  *	detection.
  *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
···
 	NL80211_EXT_FEATURE_PROT_RANGE_NEGO_AND_MEASURE,
 	NL80211_EXT_FEATURE_BSS_COLOR,
 	NL80211_EXT_FEATURE_FILS_CRYPTO_OFFLOAD,
-	NL80211_EXT_FEATURE_RADAR_OFFCHAN,
+	NL80211_EXT_FEATURE_RADAR_BACKGROUND,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,

net/mac80211/cfg.c

···
 }
 
 static int
-ieee80211_set_radar_offchan(struct wiphy *wiphy,
-			    struct cfg80211_chan_def *chandef)
+ieee80211_set_radar_background(struct wiphy *wiphy,
+			       struct cfg80211_chan_def *chandef)
 {
 	struct ieee80211_local *local = wiphy_priv(wiphy);
 
-	if (!local->ops->set_radar_offchan)
+	if (!local->ops->set_radar_background)
 		return -EOPNOTSUPP;
 
-	return local->ops->set_radar_offchan(&local->hw, chandef);
+	return local->ops->set_radar_background(&local->hw, chandef);
 }
 
 const struct cfg80211_ops mac80211_config_ops = {
···
 	.reset_tid_config = ieee80211_reset_tid_config,
 	.set_sar_specs = ieee80211_set_sar_specs,
 	.color_change = ieee80211_color_change,
-	.set_radar_offchan = ieee80211_set_radar_offchan,
+	.set_radar_background = ieee80211_set_radar_background,
 };

net/wireless/chan.c

···
 cfg80211_offchan_chain_is_active(struct cfg80211_registered_device *rdev,
 				 struct ieee80211_channel *channel)
 {
-	if (!rdev->offchan_radar_wdev)
+	if (!rdev->background_radar_wdev)
 		return false;
 
-	if (!cfg80211_chandef_valid(&rdev->offchan_radar_chandef))
+	if (!cfg80211_chandef_valid(&rdev->background_radar_chandef))
 		return false;
 
-	return cfg80211_is_sub_chan(&rdev->offchan_radar_chandef, channel);
+	return cfg80211_is_sub_chan(&rdev->background_radar_chandef, channel);
 }
 
 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,

net/wireless/core.c

···
 	INIT_WORK(&rdev->rfkill_block, cfg80211_rfkill_block_work);
 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
-	INIT_WORK(&rdev->offchan_cac_abort_wk, cfg80211_offchan_cac_abort_wk);
-	INIT_DELAYED_WORK(&rdev->offchan_cac_done_wk,
-			  cfg80211_offchan_cac_done_wk);
+	INIT_WORK(&rdev->background_cac_abort_wk,
+		  cfg80211_background_cac_abort_wk);
+	INIT_DELAYED_WORK(&rdev->background_cac_done_wk,
+			  cfg80211_background_cac_done_wk);
 
 	init_waitqueue_head(&rdev->dev_wait);
 
···
 	cancel_work_sync(&rdev->conn_work);
 	flush_work(&rdev->event_work);
 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
-	cancel_delayed_work_sync(&rdev->offchan_cac_done_wk);
+	cancel_delayed_work_sync(&rdev->background_cac_done_wk);
 	flush_work(&rdev->destroy_work);
 	flush_work(&rdev->sched_scan_stop_wk);
 	flush_work(&rdev->propagate_radar_detect_wk);
 	flush_work(&rdev->propagate_cac_done_wk);
 	flush_work(&rdev->mgmt_registrations_update_wk);
-	flush_work(&rdev->offchan_cac_abort_wk);
+	flush_work(&rdev->background_cac_abort_wk);
 
 #ifdef CONFIG_PM
 	if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
···
 
 	cfg80211_pmsr_wdev_down(wdev);
 
-	cfg80211_stop_offchan_radar_detection(wdev);
+	cfg80211_stop_background_radar_detection(wdev);
 
 	switch (wdev->iftype) {
 	case NL80211_IFTYPE_ADHOC:

net/wireless/core.h

···
 
 	struct delayed_work dfs_update_channels_wk;
 
-	struct wireless_dev *offchan_radar_wdev;
-	struct cfg80211_chan_def offchan_radar_chandef;
-	struct delayed_work offchan_cac_done_wk;
-	struct work_struct offchan_cac_abort_wk;
+	struct wireless_dev *background_radar_wdev;
+	struct cfg80211_chan_def background_radar_chandef;
+	struct delayed_work background_cac_done_wk;
+	struct work_struct background_cac_abort_wk;
 
 	/* netlink port which started critical protocol (0 means not started) */
 	u32 crit_proto_nlportid;
···
 void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev);
 
 int
-cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
-				       struct wireless_dev *wdev,
-				       struct cfg80211_chan_def *chandef);
+cfg80211_start_background_radar_detection(struct cfg80211_registered_device *rdev,
+					  struct wireless_dev *wdev,
+					  struct cfg80211_chan_def *chandef);
 
-void cfg80211_stop_offchan_radar_detection(struct wireless_dev *wdev);
+void cfg80211_stop_background_radar_detection(struct wireless_dev *wdev);
 
-void cfg80211_offchan_cac_done_wk(struct work_struct *work);
+void cfg80211_background_cac_done_wk(struct work_struct *work);
 
-void cfg80211_offchan_cac_abort_wk(struct work_struct *work);
+void cfg80211_background_cac_abort_wk(struct work_struct *work);
 
 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
 				  struct ieee80211_channel *chan);

net/wireless/mlme.c

···
 	cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_UNAVAILABLE);
 
 	if (offchan)
-		queue_work(cfg80211_wq, &rdev->offchan_cac_abort_wk);
+		queue_work(cfg80211_wq, &rdev->background_cac_abort_wk);
 
 	cfg80211_sched_dfs_chan_update(rdev);
 
···
 EXPORT_SYMBOL(cfg80211_cac_event);
 
 static void
-__cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
-			     struct wireless_dev *wdev,
-			     const struct cfg80211_chan_def *chandef,
-			     enum nl80211_radar_event event)
+__cfg80211_background_cac_event(struct cfg80211_registered_device *rdev,
+				struct wireless_dev *wdev,
+				const struct cfg80211_chan_def *chandef,
+				enum nl80211_radar_event event)
 {
 	struct wiphy *wiphy = &rdev->wiphy;
 	struct net_device *netdev;
···
 	if (!cfg80211_chandef_valid(chandef))
 		return;
 
-	if (!rdev->offchan_radar_wdev)
+	if (!rdev->background_radar_wdev)
 		return;
 
 	switch (event) {
···
 		memcpy(&rdev->cac_done_chandef, chandef, sizeof(*chandef));
 		queue_work(cfg80211_wq, &rdev->propagate_cac_done_wk);
 		cfg80211_sched_dfs_chan_update(rdev);
-		wdev = rdev->offchan_radar_wdev;
+		wdev = rdev->background_radar_wdev;
 		break;
 	case NL80211_RADAR_CAC_ABORTED:
-		if (!cancel_delayed_work(&rdev->offchan_cac_done_wk))
+		if (!cancel_delayed_work(&rdev->background_cac_done_wk))
 			return;
-		wdev = rdev->offchan_radar_wdev;
+		wdev = rdev->background_radar_wdev;
 		break;
 	case NL80211_RADAR_CAC_STARTED:
 		break;
···
 }
 
 static void
-cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
-			   const struct cfg80211_chan_def *chandef,
-			   enum nl80211_radar_event event)
+cfg80211_background_cac_event(struct cfg80211_registered_device *rdev,
+			      const struct cfg80211_chan_def *chandef,
+			      enum nl80211_radar_event event)
 {
 	wiphy_lock(&rdev->wiphy);
-	__cfg80211_offchan_cac_event(rdev, rdev->offchan_radar_wdev,
-				     chandef, event);
+	__cfg80211_background_cac_event(rdev, rdev->background_radar_wdev,
+					chandef, event);
 	wiphy_unlock(&rdev->wiphy);
 }
 
-void cfg80211_offchan_cac_done_wk(struct work_struct *work)
+void cfg80211_background_cac_done_wk(struct work_struct *work)
 {
 	struct delayed_work *delayed_work = to_delayed_work(work);
 	struct cfg80211_registered_device *rdev;
 
 	rdev = container_of(delayed_work, struct cfg80211_registered_device,
-			    offchan_cac_done_wk);
-	cfg80211_offchan_cac_event(rdev, &rdev->offchan_radar_chandef,
-				   NL80211_RADAR_CAC_FINISHED);
+			    background_cac_done_wk);
+	cfg80211_background_cac_event(rdev, &rdev->background_radar_chandef,
+				      NL80211_RADAR_CAC_FINISHED);
 }
 
-void cfg80211_offchan_cac_abort_wk(struct work_struct *work)
+void cfg80211_background_cac_abort_wk(struct work_struct *work)
 {
 	struct cfg80211_registered_device *rdev;
 
 	rdev = container_of(work, struct cfg80211_registered_device,
-			    offchan_cac_abort_wk);
-	cfg80211_offchan_cac_event(rdev, &rdev->offchan_radar_chandef,
-				   NL80211_RADAR_CAC_ABORTED);
+			    background_cac_abort_wk);
+	cfg80211_background_cac_event(rdev, &rdev->background_radar_chandef,
+				      NL80211_RADAR_CAC_ABORTED);
 }
 
-void cfg80211_offchan_cac_abort(struct wiphy *wiphy)
+void cfg80211_background_cac_abort(struct wiphy *wiphy)
 {
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 
-	queue_work(cfg80211_wq, &rdev->offchan_cac_abort_wk);
+	queue_work(cfg80211_wq, &rdev->background_cac_abort_wk);
 }
-EXPORT_SYMBOL(cfg80211_offchan_cac_abort);
+EXPORT_SYMBOL(cfg80211_background_cac_abort);
 
 int
-cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
-				       struct wireless_dev *wdev,
-				       struct cfg80211_chan_def *chandef)
+cfg80211_start_background_radar_detection(struct cfg80211_registered_device *rdev,
+					  struct wireless_dev *wdev,
+					  struct cfg80211_chan_def *chandef)
 {
 	unsigned int cac_time_ms;
 	int err;
···
 	lockdep_assert_wiphy(&rdev->wiphy);
 
 	if (!wiphy_ext_feature_isset(&rdev->wiphy,
-				     NL80211_EXT_FEATURE_RADAR_OFFCHAN))
+				     NL80211_EXT_FEATURE_RADAR_BACKGROUND))
 		return -EOPNOTSUPP;
 
 	/* Offchannel chain already locked by another wdev */
-	if (rdev->offchan_radar_wdev && rdev->offchan_radar_wdev != wdev)
+	if (rdev->background_radar_wdev && rdev->background_radar_wdev != wdev)
 		return -EBUSY;
 
 	/* CAC already in progress on the offchannel chain */
-	if (rdev->offchan_radar_wdev == wdev &&
-	    delayed_work_pending(&rdev->offchan_cac_done_wk))
+	if (rdev->background_radar_wdev == wdev &&
+	    delayed_work_pending(&rdev->background_cac_done_wk))
 		return -EBUSY;
 
-	err = rdev_set_radar_offchan(rdev, chandef);
+	err = rdev_set_radar_background(rdev, chandef);
 	if (err)
 		return err;
 
···
 	if (!cac_time_ms)
 		cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
 
-	rdev->offchan_radar_chandef = *chandef;
-	rdev->offchan_radar_wdev = wdev; /* Get offchain ownership */
+	rdev->background_radar_chandef = *chandef;
+	rdev->background_radar_wdev = wdev; /* Get offchain ownership */
 
-	__cfg80211_offchan_cac_event(rdev, wdev, chandef,
-				     NL80211_RADAR_CAC_STARTED);
-	queue_delayed_work(cfg80211_wq, &rdev->offchan_cac_done_wk,
+	__cfg80211_background_cac_event(rdev, wdev, chandef,
+					NL80211_RADAR_CAC_STARTED);
+	queue_delayed_work(cfg80211_wq, &rdev->background_cac_done_wk,
 			   msecs_to_jiffies(cac_time_ms));
 
 	return 0;
 }
 
-void cfg80211_stop_offchan_radar_detection(struct wireless_dev *wdev)
+void cfg80211_stop_background_radar_detection(struct wireless_dev *wdev)
 {
 	struct wiphy *wiphy = wdev->wiphy;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 
 	lockdep_assert_wiphy(wiphy);
 
-	if (wdev != rdev->offchan_radar_wdev)
+	if (wdev != rdev->background_radar_wdev)
 		return;
 
-	rdev_set_radar_offchan(rdev, NULL);
-	rdev->offchan_radar_wdev = NULL; /* Release offchain ownership */
+	rdev_set_radar_background(rdev, NULL);
+	rdev->background_radar_wdev = NULL; /* Release offchain ownership */
 
-	__cfg80211_offchan_cac_event(rdev, wdev, &rdev->offchan_radar_chandef,
-				     NL80211_RADAR_CAC_ABORTED);
+	__cfg80211_background_cac_event(rdev, wdev,
+					&rdev->background_radar_chandef,
+					NL80211_RADAR_CAC_ABORTED);
 }

net/wireless/nl80211.c

···
 	[NL80211_ATTR_MBSSID_CONFIG] =
 			NLA_POLICY_NESTED(nl80211_mbssid_config_policy),
 	[NL80211_ATTR_MBSSID_ELEMS] = { .type = NLA_NESTED },
-	[NL80211_ATTR_RADAR_OFFCHAN] = { .type = NLA_FLAG },
+	[NL80211_ATTR_RADAR_BACKGROUND] = { .type = NLA_FLAG },
 };
 
 /* policy for the key attributes */
···
 		goto unlock;
 	}
 
-	if (nla_get_flag(info->attrs[NL80211_ATTR_RADAR_OFFCHAN])) {
-		err = cfg80211_start_offchan_radar_detection(rdev, wdev,
-							     &chandef);
+	if (nla_get_flag(info->attrs[NL80211_ATTR_RADAR_BACKGROUND])) {
+		err = cfg80211_start_background_radar_detection(rdev, wdev,
+								&chandef);
 		goto unlock;
 	}
 

net/wireless/rdev-ops.h

···
 }
 
 static inline int
-rdev_set_radar_offchan(struct cfg80211_registered_device *rdev,
-		       struct cfg80211_chan_def *chandef)
+rdev_set_radar_background(struct cfg80211_registered_device *rdev,
+			  struct cfg80211_chan_def *chandef)
 {
 	struct wiphy *wiphy = &rdev->wiphy;
 	int ret;
 
-	if (!rdev->ops->set_radar_offchan)
+	if (!rdev->ops->set_radar_background)
 		return -EOPNOTSUPP;
 
-	trace_rdev_set_radar_offchan(wiphy, chandef);
-	ret = rdev->ops->set_radar_offchan(wiphy, chandef);
+	trace_rdev_set_radar_background(wiphy, chandef);
+	ret = rdev->ops->set_radar_background(wiphy, chandef);
 	trace_rdev_return_int(wiphy, ret);
 
 	return ret;

net/wireless/trace.h

···
 		  __entry->color_bitmap)
 );
 
-TRACE_EVENT(rdev_set_radar_offchan,
+TRACE_EVENT(rdev_set_radar_background,
 	TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef),
 
 	TP_ARGS(wiphy, chandef),