cfg80211: allow restricting supported dfs regions

At the moment, the ath9k/ath10k DFS module only supports detecting ETSI
radar patterns.
Add a bitmap in the interface combinations, indicating which DFS regions
are supported by the detector. If unset, support for all regions is
assumed.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 18 insertions, 2 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 0f1b18f209d6..c0833830cfe7 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -970,8 +970,10 @@ static int nl80211_put_iface_combinations(struct wiphy *wiphy,
                                 c->max_interfaces))
                         goto nla_put_failure;
                 if (large &&
-                    nla_put_u32(msg, NL80211_IFACE_COMB_RADAR_DETECT_WIDTHS,
-                                c->radar_detect_widths))
+                    (nla_put_u32(msg, NL80211_IFACE_COMB_RADAR_DETECT_WIDTHS,
+                                c->radar_detect_widths) ||
+                     nla_put_u32(msg, NL80211_IFACE_COMB_RADAR_DETECT_REGIONS,
+                                c->radar_detect_regions)))
                         goto nla_put_failure;
 
                 nla_nest_end(msg, nl_combi);
diff --git a/net/wireless/util.c b/net/wireless/util.c
index a756429b3a0a..8c61d5c6fad3 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1274,10 +1274,20 @@ int cfg80211_iter_combinations(struct wiphy *wiphy,
                                             void *data),
                                void *data)
 {
+        const struct ieee80211_regdomain *regdom;
+        enum nl80211_dfs_regions region = 0;
         int i, j, iftype;
         int num_interfaces = 0;
         u32 used_iftypes = 0;
 
+        if (radar_detect) {
+                rcu_read_lock();
+                regdom = rcu_dereference(cfg80211_regdomain);
+                if (regdom)
+                        region = regdom->dfs_region;
+                rcu_read_unlock();
+        }
+
         for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
                 num_interfaces += iftype_num[iftype];
                 if (iftype_num[iftype] > 0 &&
@@ -1318,6 +1328,10 @@ int cfg80211_iter_combinations(struct wiphy *wiphy,
                 if (radar_detect != (c->radar_detect_widths & radar_detect))
                         goto cont;
 
+                if (radar_detect && c->radar_detect_regions &&
+                    !(c->radar_detect_regions & BIT(region)))
+                        goto cont;
+
                 /* Finally check that all iftypes that we're currently
                  * using are actually part of this combination. If they
                  * aren't then we can't use this combination and have