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>

5 files changed, 62 insertions, 51 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
index cd1bff5..e10e0ca 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rs.c
@@ -1133,8 +1133,7 @@ static int rs_switch_to_mimo2(struct iwl_priv *priv,
 	s32 rate;
 	s8 is_green = lq_sta->is_green;
 
-	if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
-	    !sta->ht_cap.ht_supported)
+	if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
 		return -1;
 
 	if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
@@ -1201,8 +1200,7 @@ static int rs_switch_to_siso(struct iwl_priv *priv,
 	u8 is_green = lq_sta->is_green;
 	s32 rate;
 
-	if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
-	    !sta->ht_cap.ht_supported)
+	if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
 		return -1;
 
 	IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
@@ -2001,9 +1999,8 @@ lq_update:
 		 * stay with best antenna legacy modulation for a while
 		 * before next round of mode comparisons. */
 		tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
-		if (is_legacy(tbl1->lq_type) &&
-		   (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE)) &&
-		    (lq_sta->action_counter >= 1)) {
+		if (is_legacy(tbl1->lq_type) && !conf->ht.enabled &&
+		    lq_sta->action_counter >= 1) {
 			lq_sta->action_counter = 0;
 			IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
 			rs_set_stay_in_table(priv, 1, lq_sta);
@@ -2238,19 +2235,19 @@ static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
 	 * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
 	 * supp_rates[] does not; shift to convert format, force 9 MBits off.
 	 */
-	lq_sta->active_siso_rate = conf->ht_cap.mcs.rx_mask[0] << 1;
-	lq_sta->active_siso_rate |= conf->ht_cap.mcs.rx_mask[0] & 0x1;
+	lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
+	lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
 	lq_sta->active_siso_rate &= ~((u16)0x2);
 	lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
 
 	/* Same here */
-	lq_sta->active_mimo2_rate = conf->ht_cap.mcs.rx_mask[1] << 1;
-	lq_sta->active_mimo2_rate |= conf->ht_cap.mcs.rx_mask[1] & 0x1;
+	lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
+	lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
 	lq_sta->active_mimo2_rate &= ~((u16)0x2);
 	lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
 
-	lq_sta->active_mimo3_rate = conf->ht_cap.mcs.rx_mask[2] << 1;
-	lq_sta->active_mimo3_rate |= conf->ht_cap.mcs.rx_mask[2] & 0x1;
+	lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
+	lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
 	lq_sta->active_mimo3_rate &= ~((u16)0x2);
 	lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
 
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 79a2441..7c3eb3d 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -552,17 +552,30 @@ static int iwl4965_send_beacon_cmd(struct iwl_priv *priv)
 static void iwl4965_ht_conf(struct iwl_priv *priv,
 			    struct ieee80211_bss_conf *bss_conf)
 {
-	struct ieee80211_sta_ht_cap *ht_conf = bss_conf->ht_cap;
-	struct ieee80211_ht_bss_info *ht_bss_conf = bss_conf->ht_bss_conf;
+	struct ieee80211_sta_ht_cap *ht_conf;
 	struct iwl_ht_info *iwl_conf = &priv->current_ht_config;
+	struct ieee80211_sta *sta;
 
 	IWL_DEBUG_MAC80211("enter: \n");
 
-	iwl_conf->is_ht = bss_conf->assoc_ht;
-
 	if (!iwl_conf->is_ht)
 		return;
 
+
+	/*
+	 * It is totally wrong to base global information on something
+	 * that is valid only when associated, alas, this driver works
+	 * that way and I don't know how to fix it.
+	 */
+
+	rcu_read_lock();
+	sta = ieee80211_find_sta(priv->hw, priv->bssid);
+	if (!sta) {
+		rcu_read_unlock();
+		return;
+	}
+	ht_conf = &sta->ht_cap;
+
 	if (ht_conf->cap & IEEE80211_HT_CAP_SGI_20)
 		iwl_conf->sgf |= HT_SHORT_GI_20MHZ;
 	if (ht_conf->cap & IEEE80211_HT_CAP_SGI_40)
@@ -574,8 +587,8 @@ static void iwl4965_ht_conf(struct iwl_priv *priv,
 
 	iwl_conf->supported_chan_width =
 		!!(ht_conf->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40);
-	iwl_conf->extension_chan_offset =
-		ht_bss_conf->bss_cap & IEEE80211_HT_PARAM_CHA_SEC_OFFSET;
+
+	iwl_conf->extension_chan_offset = bss_conf->ht.secondary_channel_offset;
 	/* If no above or below channel supplied disable FAT channel */
 	if (iwl_conf->extension_chan_offset != IEEE80211_HT_PARAM_CHA_SEC_ABOVE &&
 	    iwl_conf->extension_chan_offset != IEEE80211_HT_PARAM_CHA_SEC_BELOW) {
@@ -587,15 +600,14 @@ static void iwl4965_ht_conf(struct iwl_priv *priv,
 
 	memcpy(&iwl_conf->mcs, &ht_conf->mcs, 16);
 
-	iwl_conf->control_channel = ht_bss_conf->primary_channel;
-	iwl_conf->tx_chan_width =
-		!!(ht_bss_conf->bss_cap & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY);
+	iwl_conf->tx_chan_width = bss_conf->ht.width_40_ok;
 	iwl_conf->ht_protection =
-		ht_bss_conf->bss_op_mode & IEEE80211_HT_OP_MODE_PROTECTION;
+		bss_conf->ht.operation_mode & IEEE80211_HT_OP_MODE_PROTECTION;
 	iwl_conf->non_GF_STA_present =
-		!!(ht_bss_conf->bss_op_mode & IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT);
+		!!(bss_conf->ht.operation_mode & IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT);
+
+	rcu_read_unlock();
 
-	IWL_DEBUG_MAC80211("control channel %d\n", iwl_conf->control_channel);
 	IWL_DEBUG_MAC80211("leave\n");
 }
 
@@ -2746,6 +2758,8 @@ static int iwl4965_mac_config(struct ieee80211_hw *hw, u32 changed)
 	mutex_lock(&priv->mutex);
 	IWL_DEBUG_MAC80211("enter to channel %d\n", conf->channel->hw_value);
 
+	priv->current_ht_config.is_ht = conf->ht.enabled;
+
 	if (conf->radio_enabled && iwl_radio_kill_sw_enable_radio(priv)) {
 		IWL_DEBUG_MAC80211("leave - RF-KILL - waiting for uCode\n");
 		goto out;
@@ -3104,7 +3118,6 @@ static void iwl4965_bss_info_changed(struct ieee80211_hw *hw,
 	}
 
 	if (changes & BSS_CHANGED_HT) {
-		IWL_DEBUG_MAC80211("HT %d\n", bss_conf->assoc_ht);
 		iwl4965_ht_conf(priv, bss_conf);
 		iwl_set_rxon_chain(priv);
 	}
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 4678da4..10f5a0a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -637,8 +637,8 @@ u8 iwl_is_fat_tx_allowed(struct iwl_priv *priv,
 	}
 
 	return iwl_is_channel_extension(priv, priv->band,
-					 iwl_ht_conf->control_channel,
-					 iwl_ht_conf->extension_chan_offset);
+					le16_to_cpu(priv->staging_rxon.channel),
+					iwl_ht_conf->extension_chan_offset);
 }
 EXPORT_SYMBOL(iwl_is_fat_tx_allowed);
 
@@ -663,13 +663,6 @@ void iwl_set_rxon_ht(struct iwl_priv *priv, struct iwl_ht_info *ht_info)
 		rxon->flags &= ~(RXON_FLG_CHANNEL_MODE_MIXED_MSK |
 				 RXON_FLG_CHANNEL_MODE_PURE_40_MSK);
 
-	if (le16_to_cpu(rxon->channel) != ht_info->control_channel) {
-		IWL_DEBUG_ASSOC("control diff than current %d %d\n",
-				le16_to_cpu(rxon->channel),
-				ht_info->control_channel);
-		return;
-	}
-
 	/* Note: control channel is opposite of extension channel */
 	switch (ht_info->extension_chan_offset) {
 	case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
@@ -692,14 +685,12 @@ void iwl_set_rxon_ht(struct iwl_priv *priv, struct iwl_ht_info *ht_info)
 
 	IWL_DEBUG_ASSOC("supported HT rate 0x%X 0x%X 0x%X "
 			"rxon flags 0x%X operation mode :0x%X "
-			"extension channel offset 0x%x "
-			"control chan %d\n",
+			"extension channel offset 0x%x\n",
 			ht_info->mcs.rx_mask[0],
 			ht_info->mcs.rx_mask[1],
 			ht_info->mcs.rx_mask[2],
 			le32_to_cpu(rxon->flags), ht_info->ht_protection,
-			ht_info->extension_chan_offset,
-			ht_info->control_channel);
+			ht_info->extension_chan_offset);
 	return;
 }
 EXPORT_SYMBOL(iwl_set_rxon_ht);
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 572250e..2e95149 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -413,7 +413,6 @@ struct iwl_ht_info {
 	u8 mpdu_density;
 	struct ieee80211_mcs_info mcs;
 	/* BSS related data */
-	u8 control_channel;
 	u8 extension_chan_offset;
 	u8 tx_chan_width;
 	u8 ht_protection;
diff --git a/drivers/net/wireless/iwlwifi/iwl-sta.c b/drivers/net/wireless/iwlwifi/iwl-sta.c
index b9b8554..218483d 100644
--- a/drivers/net/wireless/iwlwifi/iwl-sta.c
+++ b/drivers/net/wireless/iwlwifi/iwl-sta.c
@@ -890,20 +890,31 @@ static void iwl_sta_init_lq(struct iwl_priv *priv, const u8 *addr, int is_ap)
  */
 int iwl_rxon_add_station(struct iwl_priv *priv, const u8 *addr, int is_ap)
 {
+	struct ieee80211_sta *sta;
+	struct ieee80211_sta_ht_cap ht_config;
+	struct ieee80211_sta_ht_cap *cur_ht_config = NULL;
 	u8 sta_id;
 
 	/* Add station to device's station table */
-	struct ieee80211_conf *conf = &priv->hw->conf;
-	struct ieee80211_sta_ht_cap *cur_ht_config = &conf->ht_cap;
-
-	if ((is_ap) &&
-	    (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
-	    (priv->iw_mode == NL80211_IFTYPE_STATION))
-		sta_id = iwl_add_station_flags(priv, addr, is_ap,
-						   0, cur_ht_config);
-	else
-		sta_id = iwl_add_station_flags(priv, addr, is_ap,
-						   0, NULL);
+
+	/*
+	 * XXX: This check is definitely not correct, if we're an AP
+	 *	it'll always be false which is not what we want, but
+	 *	it doesn't look like iwlagn is prepared to be an HT
+	 *	AP anyway.
+	 */
+	if (priv->current_ht_config.is_ht) {
+		rcu_read_lock();
+		sta = ieee80211_find_sta(priv->hw, addr);
+		if (sta) {
+			memcpy(&ht_config, &sta->ht_cap, sizeof(ht_config));
+			cur_ht_config = &ht_config;
+		}
+		rcu_read_unlock();
+	}
+
+	sta_id = iwl_add_station_flags(priv, addr, is_ap,
+				       0, cur_ht_config);
 
 	/* Set up default rate scaling table in device's station table */
 	iwl_sta_init_lq(priv, addr, is_ap);