mac80211: explicitly copy channels to VLANs where needed

Currently the code assigns channel contexts to VLANs
(for use by the TX/RX code) when the AP master gets
its channel context assigned. This works fine, but
in the upcoming radar detection work the VLANs don't
require a channel context (during radar detection)
and assigning one to them anyway causes issues with
locking and also inconsistencies -- a VLAN interface
that is added before radar detection would get the
channel context, while one added during it wouldn't.

Fix these issues moving the channel context copying
to a new explicit operation that will not be used
in the radar detection code.

Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index f4f7e7691077..8f6b593a921f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -933,6 +933,7 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
                                         IEEE80211_CHANCTX_SHARED);
         if (err)
                 return err;
+        ieee80211_vif_copy_chanctx_to_vlans(sdata, false);
 
         /*
          * Apply control port protocol, this allows us to
@@ -1047,6 +1048,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
         local->total_ps_buffered -= skb_queue_len(&sdata->u.ap.ps.bc_buf);
         skb_queue_purge(&sdata->u.ap.ps.bc_buf);
 
+        ieee80211_vif_copy_chanctx_to_vlans(sdata, true);
         ieee80211_vif_release_channel(sdata);
 
         return 0;