mac80211: rewrite HT handling

The HT handling has the following deficiencies, which I've
(partially) fixed:
 * it always uses the AP info even if there is no AP,
   hence has no chance of working as an AP
 * it pretends to be HW config, but really is per-BSS
 * channel sanity checking is left to the drivers
 * it generally lets the driver control too much

HT enabling is still wrong with this patch if you have more than
one virtual STA mode interface, but that never happens currently.
Once WDS, IBSS or AP/VLAN gets HT capabilities, it will also be
wrong, see the comment in ieee80211_enable_ht().

Additionally, this fixes a number of bugs:
 * mac80211: ieee80211_set_disassoc doesn't notify the driver any
             more since the refactoring
 * iwl-agn-rs: always uses the HT capabilities from the wrong stuff
               mac80211 gives it rather than the actual peer STA
 * ath9k: a number of bugs resulting from the broken HT API

I'm not entirely happy with putting the HT capabilities into
struct ieee80211_sta as restricted to our own HT TX capabilities,
but I see no cleaner solution for now.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 50 insertions, 38 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 9c5f5c37a49e..39bc9c69893b 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -700,14 +700,15 @@ static void ieee80211_sta_send_associnfo(struct ieee80211_sub_if_data *sdata,
 
 
 static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
-                                     struct ieee80211_if_sta *ifsta)
+                                     struct ieee80211_if_sta *ifsta,
+                                     u32 bss_info_changed)
 {
         struct ieee80211_local *local = sdata->local;
         struct ieee80211_conf *conf = &local_to_hw(local)->conf;
-        u32 changed = BSS_CHANGED_ASSOC;
 
         struct ieee80211_bss *bss;
 
+        bss_info_changed |= BSS_CHANGED_ASSOC;
         ifsta->flags |= IEEE80211_STA_ASSOCIATED;
 
         if (sdata->vif.type != NL80211_IFTYPE_STATION)
@@ -722,19 +723,12 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
                 sdata->vif.bss_conf.timestamp = bss->timestamp;
                 sdata->vif.bss_conf.dtim_period = bss->dtim_period;
 
-                changed |= ieee80211_handle_bss_capability(sdata,
+                bss_info_changed |= ieee80211_handle_bss_capability(sdata,
                         bss->capability, bss->has_erp_value, bss->erp_value);
 
                 ieee80211_rx_bss_put(local, bss);
         }
 
-        if (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) {
-                changed |= BSS_CHANGED_HT;
-                sdata->vif.bss_conf.assoc_ht = 1;
-                sdata->vif.bss_conf.ht_cap = &conf->ht_cap;
-                sdata->vif.bss_conf.ht_bss_conf = &conf->ht_bss_conf;
-        }
-
         ifsta->flags |= IEEE80211_STA_PREV_BSSID_SET;
         memcpy(ifsta->prev_bssid, sdata->u.sta.bssid, ETH_ALEN);
         ieee80211_sta_send_associnfo(sdata, ifsta);
@@ -748,8 +742,8 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
          * when we have associated, we aren't checking whether it actually
          * changed or not.
          */
-        changed |= BSS_CHANGED_BASIC_RATES;
-        ieee80211_bss_info_change_notify(sdata, changed);
+        bss_info_changed |= BSS_CHANGED_BASIC_RATES;
+        ieee80211_bss_info_change_notify(sdata, bss_info_changed);
 
         netif_tx_start_all_queues(sdata->dev);
         netif_carrier_on(sdata->dev);
@@ -813,7 +807,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 {
         struct ieee80211_local *local = sdata->local;
         struct sta_info *sta;
-        u32 changed = BSS_CHANGED_ASSOC;
+        u32 changed = 0;
 
         rcu_read_lock();
 
@@ -847,15 +841,9 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
         ifsta->flags &= ~IEEE80211_STA_ASSOCIATED;
         changed |= ieee80211_reset_erp_info(sdata);
 
-        if (sdata->vif.bss_conf.assoc_ht)
-                changed |= BSS_CHANGED_HT;
-
-        sdata->vif.bss_conf.assoc_ht = 0;
-        sdata->vif.bss_conf.ht_cap = NULL;
-        sdata->vif.bss_conf.ht_bss_conf = NULL;
-
         ieee80211_led_assoc(local, 0);
-        sdata->vif.bss_conf.assoc = 0;
+        changed |= BSS_CHANGED_ASSOC;
+        sdata->vif.bss_conf.assoc = false;
 
         ieee80211_sta_send_apinfo(sdata, ifsta);
 
@@ -867,6 +855,11 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
         rcu_read_unlock();
 
         sta_info_destroy(sta);
+
+        local->hw.conf.ht.enabled = false;
+        ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_HT);
+
+        ieee80211_bss_info_change_notify(sdata, changed);
 }
 
 static int ieee80211_sta_wep_configured(struct ieee80211_sub_if_data *sdata)
@@ -1184,8 +1177,10 @@ static void ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         struct ieee802_11_elems elems;
         struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
         u8 *pos;
+        u32 changed = 0;
         int i, j;
         bool have_higher_than_11mbit = false;
+        u16 ap_ht_cap_flags;
 
         /* AssocResp and ReassocResp have identical structure, so process both
          * of them in this function. */
@@ -1333,15 +1328,11 @@ static void ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         else
                 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
 
-        if (elems.ht_cap_elem && elems.ht_info_elem && elems.wmm_param &&
-            (ifsta->flags & IEEE80211_STA_WMM_ENABLED)) {
-                struct ieee80211_ht_bss_info bss_info;
-                ieee80211_ht_cap_ie_to_sta_ht_cap(
+        if (elems.ht_cap_elem)
+                ieee80211_ht_cap_ie_to_sta_ht_cap(sband,
                                 elems.ht_cap_elem, &sta->sta.ht_cap);
-                ieee80211_ht_info_ie_to_ht_bss_info(
-                                elems.ht_info_elem, &bss_info);
-                ieee80211_handle_ht(local, &sta->sta.ht_cap, &bss_info);
-        }
+
+        ap_ht_cap_flags = sta->sta.ht_cap.cap;
 
         rate_control_rate_init(sta);
 
@@ -1353,11 +1344,16 @@ static void ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         } else
                 rcu_read_unlock();
 
+        if (elems.ht_info_elem && elems.wmm_param &&
+            (ifsta->flags & IEEE80211_STA_WMM_ENABLED))
+                changed |= ieee80211_enable_ht(sdata, elems.ht_info_elem,
+                                               ap_ht_cap_flags);
+
         /* set AID and assoc capability,
          * ieee80211_set_associated() will tell the driver */
         bss_conf->aid = aid;
         bss_conf->assoc_capability = capab_info;
-        ieee80211_set_associated(sdata, ifsta);
+        ieee80211_set_associated(sdata, ifsta, changed);
 
         ieee80211_associated(sdata, ifsta);
 }
@@ -1657,7 +1653,6 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
         size_t baselen;
         struct ieee802_11_elems elems;
         struct ieee80211_local *local = sdata->local;
-        struct ieee80211_conf *conf = &local->hw.conf;
         u32 changed = 0;
         bool erp_valid;
         u8 erp_value = 0;
@@ -1693,14 +1688,31 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                         le16_to_cpu(mgmt->u.beacon.capab_info),
                         erp_valid, erp_value);
 
-        if (elems.ht_cap_elem && elems.ht_info_elem &&
-            elems.wmm_param && conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) {
-                struct ieee80211_ht_bss_info bss_info;
 
-                ieee80211_ht_info_ie_to_ht_bss_info(
-                                elems.ht_info_elem, &bss_info);
-                changed |= ieee80211_handle_ht(local, &conf->ht_cap,
-                                               &bss_info);
+        if (elems.ht_cap_elem && elems.ht_info_elem && elems.wmm_param) {
+                struct sta_info *sta;
+                struct ieee80211_supported_band *sband;
+                u16 ap_ht_cap_flags;
+
+                rcu_read_lock();
+
+                sta = sta_info_get(local, ifsta->bssid);
+                if (!sta) {
+                        rcu_read_unlock();
+                        return;
+                }
+
+                sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
+
+                ieee80211_ht_cap_ie_to_sta_ht_cap(sband,
+                                elems.ht_cap_elem, &sta->sta.ht_cap);
+
+                ap_ht_cap_flags = sta->sta.ht_cap.cap;
+
+                rcu_read_unlock();
+
+                changed |= ieee80211_enable_ht(sdata, elems.ht_info_elem,
+                                               ap_ht_cap_flags);
         }
 
         ieee80211_bss_info_change_notify(sdata, changed);