iwlwifi: clean up last_phy_res

The last_phy_res[100] variable is used in an odd
way. The first byte of it is used as a flag, and
the rest as the data. Thus, the array need only
be 61 bytes, since it is just the flag and a
struct iwl_rx_phy_res (which is 60 bytes).

Clean this up by splitting the variable into two:
last_phy_res and last_phy_res_valid, using correct
types for both (struct and bool). While doing all
this also move the variables to the _agn part of
the hw-specific union since they only apply to
A-MPDUs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>

drivers/net/wireless/iwlwifi/iwl-agn-lib.c

@@ -1001,11 +1001,11 @@ void iwlagn_rx_reply_rx(struct iwl_priv *priv,
 				phy_res->cfg_phy_cnt + len);
 		ampdu_status = le32_to_cpu(rx_pkt_status);
 	} else {
-		if (!priv->last_phy_res[0]) {
+		if (!priv->_agn.last_phy_res_valid) {
 			IWL_ERR(priv, "MPDU frame without cached PHY data\n");
 			return;
 		}
-		phy_res = (struct iwl_rx_phy_res *)&priv->last_phy_res[1];
+		phy_res = &priv->_agn.last_phy_res;
 		amsdu = (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
 		header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*amsdu));
 		len = le16_to_cpu(amsdu->byte_count);
@@ -1097,7 +1097,7 @@ void iwlagn_rx_reply_rx_phy(struct iwl_priv *priv,
 			    struct iwl_rx_mem_buffer *rxb)
 {
 	struct iwl_rx_packet *pkt = rxb_addr(rxb);
-	priv->last_phy_res[0] = 1;
-	memcpy(&priv->last_phy_res[1], &(pkt->u.raw[0]),
+	priv->_agn.last_phy_res_valid = true;
+	memcpy(&priv->_agn.last_phy_res, pkt->u.raw,
 	       sizeof(struct iwl_rx_phy_res));
 }

drivers/net/wireless/iwlwifi/iwl-dev.h

@@ -1120,7 +1120,6 @@ struct iwl_priv {
 	__le16 sensitivity_tbl[HD_TABLE_SIZE];
 
 	struct iwl_ht_config current_ht_config;
-	u8 last_phy_res[100];
 
 	/* Rate scaling data */
 	u8 retry_rate;
@@ -1237,6 +1236,9 @@ struct iwl_priv {
 			 * no AGGREGATION
 			 */
 			u8 agg_tids_count;
+
+			struct iwl_rx_phy_res last_phy_res;
+			bool last_phy_res_valid;
 		} _agn;
 #endif
 	};