cfg80211: rework chandef checking and export it

Some of the chandef checking that we do in cfg80211
to check if a channel is supported or not is also
needed in mac80211, so rework that a bit and export
the functions that are needed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 63 insertions, 29 deletions

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index bf2dfd54ff3b..b5f69831e318 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -44,7 +44,7 @@ void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
 }
 EXPORT_SYMBOL(cfg80211_chandef_create);
 
-bool cfg80211_chan_def_valid(const struct cfg80211_chan_def *chandef)
+bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
 {
         u32 control_freq;
 
@@ -105,6 +105,7 @@ bool cfg80211_chan_def_valid(const struct cfg80211_chan_def *chandef)
 
         return true;
 }
+EXPORT_SYMBOL(cfg80211_chandef_valid);
 
 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
                                   int *pri40, int *pri80)
@@ -187,9 +188,9 @@ cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
 }
 EXPORT_SYMBOL(cfg80211_chandef_compatible);
 
-bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
-                                 u32 center_freq, u32 bandwidth,
-                                 u32 prohibited_flags)
+static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
+                                        u32 center_freq, u32 bandwidth,
+                                        u32 prohibited_flags)
 {
         struct ieee80211_channel *c;
         u32 freq;
@@ -205,55 +206,88 @@ bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
         return true;
 }
 
-static bool cfg80211_check_beacon_chans(struct wiphy *wiphy,
-                                        u32 center_freq, u32 bw)
+bool cfg80211_chandef_usable(struct wiphy *wiphy,
+                             const struct cfg80211_chan_def *chandef,
+                             u32 prohibited_flags)
 {
-        return cfg80211_secondary_chans_ok(wiphy, center_freq, bw,
-                                           IEEE80211_CHAN_DISABLED |
-                                           IEEE80211_CHAN_PASSIVE_SCAN |
-                                           IEEE80211_CHAN_NO_IBSS |
-                                           IEEE80211_CHAN_RADAR);
-}
+        struct ieee80211_sta_ht_cap *ht_cap;
+        struct ieee80211_sta_vht_cap *vht_cap;
+        u32 width, control_freq;
 
-bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
-                             struct cfg80211_chan_def *chandef)
-{
-        u32 width;
-        bool res;
+        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
+                return false;
 
-        trace_cfg80211_reg_can_beacon(wiphy, chandef);
+        ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
+        vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
 
-        if (WARN_ON(!cfg80211_chan_def_valid(chandef))) {
-                trace_cfg80211_return_bool(false);
-                return false;
-        }
+        control_freq = chandef->chan->center_freq;
 
         switch (chandef->width) {
-        case NL80211_CHAN_WIDTH_20_NOHT:
         case NL80211_CHAN_WIDTH_20:
+                if (!ht_cap->ht_supported)
+                        return false;
+        case NL80211_CHAN_WIDTH_20_NOHT:
                 width = 20;
                 break;
         case NL80211_CHAN_WIDTH_40:
                 width = 40;
+                if (!ht_cap->ht_supported)
+                        return false;
+                if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
+                    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
+                        return false;
+                if (chandef->center_freq1 < control_freq &&
+                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
+                        return false;
+                if (chandef->center_freq1 > control_freq &&
+                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
+                        return false;
                 break;
-        case NL80211_CHAN_WIDTH_80:
         case NL80211_CHAN_WIDTH_80P80:
+                if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ))
+                        return false;
+        case NL80211_CHAN_WIDTH_80:
+                if (!vht_cap->vht_supported)
+                        return false;
                 width = 80;
                 break;
         case NL80211_CHAN_WIDTH_160:
+                if (!vht_cap->vht_supported)
+                        return false;
+                if (!(vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ))
+                        return false;
                 width = 160;
                 break;
         default:
                 WARN_ON_ONCE(1);
-                trace_cfg80211_return_bool(false);
                 return false;
         }
 
-        res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq1, width);
+        /* TODO: missing regulatory check on 80/160 bandwidth */
+
+        if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
+                                         width, prohibited_flags))
+                return false;
+
+        if (!chandef->center_freq2)
+                return true;
+        return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
+                                           width, prohibited_flags);
+}
+EXPORT_SYMBOL(cfg80211_chandef_usable);
+
+bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
+                             struct cfg80211_chan_def *chandef)
+{
+        bool res;
+
+        trace_cfg80211_reg_can_beacon(wiphy, chandef);
 
-        if (res && chandef->center_freq2)
-                res = cfg80211_check_beacon_chans(wiphy, chandef->center_freq2,
-                                                  width);
+        res = cfg80211_chandef_usable(wiphy, chandef,
+                                      IEEE80211_CHAN_DISABLED |
+                                      IEEE80211_CHAN_PASSIVE_SCAN |
+                                      IEEE80211_CHAN_NO_IBSS |
+                                      IEEE80211_CHAN_RADAR);
 
         trace_cfg80211_return_bool(res);
         return res;