cfg80211/mac80211: refactor cfg80211_chandef_dfs_required()

Some interface types don't require DFS (such as STATION, P2P_CLIENT
etc).  In order to centralize these decisions, make
cfg80211_chandef_dfs_required() take the iftype into consideration.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 78 insertions, 40 deletions

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index c3180dc03a33..c61bcdd3dfbc 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -326,28 +326,57 @@ static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
 
 
 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
-				  const struct cfg80211_chan_def *chandef)
+				  const struct cfg80211_chan_def *chandef,
+				  enum nl80211_iftype iftype)
 {
 	int width;
-	int r;
+	int ret;
 
 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 		return -EINVAL;
 
-	width = cfg80211_chandef_get_width(chandef);
-	if (width < 0)
-		return -EINVAL;
+	switch (iftype) {
+	case NL80211_IFTYPE_ADHOC:
+	case NL80211_IFTYPE_AP:
+	case NL80211_IFTYPE_P2P_GO:
+	case NL80211_IFTYPE_MESH_POINT:
+		width = cfg80211_chandef_get_width(chandef);
+		if (width < 0)
+			return -EINVAL;
 
-	r = cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq1,
-					    width);
-	if (r)
-		return r;
+		ret = cfg80211_get_chans_dfs_required(wiphy,
+						      chandef->center_freq1,
+						      width);
+		if (ret < 0)
+			return ret;
+		else if (ret > 0)
+			return BIT(chandef->width);
 
-	if (!chandef->center_freq2)
-		return 0;
+		if (!chandef->center_freq2)
+			return 0;
+
+		ret = cfg80211_get_chans_dfs_required(wiphy,
+						      chandef->center_freq2,
+						      width);
+		if (ret < 0)
+			return ret;
+		else if (ret > 0)
+			return BIT(chandef->width);
 
-	return cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq2,
-					       width);
+		break;
+	case NL80211_IFTYPE_STATION:
+	case NL80211_IFTYPE_P2P_CLIENT:
+	case NL80211_IFTYPE_MONITOR:
+	case NL80211_IFTYPE_AP_VLAN:
+	case NL80211_IFTYPE_WDS:
+	case NL80211_IFTYPE_P2P_DEVICE:
+	case NL80211_IFTYPE_UNSPECIFIED:
+		break;
+	case NUM_NL80211_IFTYPES:
+		WARN_ON(1);
+	}
+
+	return 0;
 }
 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
 
@@ -749,7 +778,8 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 	    !cfg80211_go_permissive_chan(rdev, chandef->chan))
 		prohibited_flags |= IEEE80211_CHAN_NO_IR;
 
-	if (cfg80211_chandef_dfs_required(wiphy, chandef) > 0 &&
+	if (cfg80211_chandef_dfs_required(wiphy, chandef,
+					  NL80211_IFTYPE_UNSPECIFIED) > 0 &&
 	    cfg80211_chandef_dfs_available(wiphy, chandef)) {
 		/* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 		prohibited_flags = IEEE80211_CHAN_DISABLED;
@@ -779,6 +809,8 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 		        enum cfg80211_chan_mode *chanmode,
 		        u8 *radar_detect)
 {
+	int ret;
+
 	*chan = NULL;
 	*chanmode = CHAN_MODE_UNDEFINED;
 
@@ -821,8 +853,11 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chan = wdev->chandef.chan;
 			*chanmode = CHAN_MODE_SHARED;
 
-			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef))
+			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
+							    &wdev->chandef,
+							    wdev->iftype);
+			WARN_ON(ret < 0);
+			if (ret > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
@@ -831,8 +866,11 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chan = wdev->chandef.chan;
 			*chanmode = CHAN_MODE_SHARED;
 
-			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef))
+			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
+							    &wdev->chandef,
+							    wdev->iftype);
+			WARN_ON(ret < 0);
+			if (ret > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
index 7031ee0afad8..6ebe883653a4 100644
--- a/net/wireless/mesh.c
+++ b/net/wireless/mesh.c
@@ -179,10 +179,13 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 				     NL80211_IFTYPE_MESH_POINT))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &setup->chandef);
+	err = cfg80211_chandef_dfs_required(wdev->wiphy,
+					    &setup->chandef,
+					    NL80211_IFTYPE_MESH_POINT);
 	if (err < 0)
 		return err;
-	if (err)
+
+	if (err > 0)
 		radar_detect_width = BIT(setup->chandef.width);
 
 	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 85bc830fd7e3..4f82b9b71db1 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3275,12 +3275,15 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 				     wdev->iftype))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &params.chandef);
+	err = cfg80211_chandef_dfs_required(wdev->wiphy,
+					    &params.chandef,
+					    NL80211_IFTYPE_AP);
 	if (err < 0)
 		return err;
-	if (err) {
-		radar_detect_width = BIT(params.chandef.width);
+
+	if (err > 0) {
 		params.radar_required = true;
+		radar_detect_width = BIT(params.chandef.width);
 	}
 
 	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
@@ -5806,7 +5809,8 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (wdev->cac_started)
 		return -EBUSY;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &chandef);
+	err = cfg80211_chandef_dfs_required(wdev->wiphy, &chandef,
+					    NL80211_IFTYPE_UNSPECIFIED);
 	if (err < 0)
 		return err;
 
@@ -5942,22 +5946,15 @@ skip_beacons:
 				     wdev->iftype))
 		return -EINVAL;
 
-	switch (dev->ieee80211_ptr->iftype) {
-	case NL80211_IFTYPE_AP:
-	case NL80211_IFTYPE_P2P_GO:
-	case NL80211_IFTYPE_ADHOC:
-	case NL80211_IFTYPE_MESH_POINT:
-		err = cfg80211_chandef_dfs_required(wdev->wiphy,
-						    &params.chandef);
-		if (err < 0)
-			return err;
-		if (err) {
-			radar_detect_width = BIT(params.chandef.width);
-			params.radar_required = true;
-		}
-		break;
-	default:
-		break;
+	err = cfg80211_chandef_dfs_required(wdev->wiphy,
+					    &params.chandef,
+					    wdev->iftype);
+	if (err < 0)
+		return err;
+
+	if (err > 0) {
+		radar_detect_width = BIT(params.chandef.width);
+		params.radar_required = true;
 	}
 
 	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,