qcacld-3.0: Move cache sta info to hash based

Currently in hdd_adapter, the variable cache_sta_info is an array of
hdd_station_info structured indexed by the sta_id. As sta_id is no
longer used, this array based implementation becomes unnecessary.

Move the sta_info implementation to a hash table implementation.

Change-Id: Iac11ecd2ae4a454649235cf8763e9a5f80e7eb38
CRs-Fixed: 2515316

core/hdd/inc/wlan_hdd_main.h

@@ -1042,6 +1042,7 @@ struct hdd_context;
  * @event_flags: a bitmap of hdd_adapter_flags
  * @mic_work: mic work information
  * @gpio_tsf_sync_work: work to sync send TSF CAP WMI command
+ * @cache_sta_count: number of currently cached stations
  *
  */
 struct hdd_adapter {
@@ -1145,6 +1146,7 @@ struct hdd_adapter {
 	/* TODO: _list from name will be removed after clean up */
 	struct hdd_sta_info_obj sta_info_list;
 	struct hdd_sta_info_obj cache_sta_info_list;
+	qdf_atomic_t cache_sta_count;
 
 #ifdef FEATURE_WLAN_WAPI
 	struct hdd_wapi_info wapi_info;

core/hdd/src/wlan_hdd_hostapd.c

@@ -1443,15 +1443,11 @@ static int hdd_convert_dot11mode_from_phymode(int phymode)
 static void hdd_fill_station_info(struct hdd_adapter *adapter,
 				  tSap_StationAssocReassocCompleteEvent *event)
 {
-	struct hdd_station_info *stainfo;
-	uint8_t i = 0, oldest_disassoc_sta_idx = WLAN_MAX_STA_COUNT + 1;
+	struct hdd_station_info *stainfo, *cache_sta_info;
+	struct hdd_station_info *oldest_disassoc_sta_info = NULL;
+	uint8_t index = 0;
 	qdf_time_t oldest_disassoc_sta_ts = 0;
 
-	if (event->staId >= WLAN_MAX_STA_COUNT) {
-		hdd_err("invalid sta id");
-		return;
-	}
-
 	stainfo = hdd_get_sta_info_by_mac(&adapter->sta_info_list,
 					  event->staMac.bytes);
 
@@ -1512,46 +1508,55 @@ static void hdd_fill_station_info(struct hdd_adapter *adapter,
 	stainfo->dhcp_phase = DHCP_PHASE_ACK;
 	stainfo->dhcp_nego_status = DHCP_NEGO_STOP;
 
-	while (i < WLAN_MAX_STA_COUNT) {
-		if (!qdf_mem_cmp(adapter->cache_sta_info[i].sta_mac.bytes,
-				 event->staMac.bytes,
-				 QDF_MAC_ADDR_SIZE))
-			break;
-		i++;
-	}
-	if (i >= WLAN_MAX_STA_COUNT) {
-		i = 0;
-		while (i < WLAN_MAX_STA_COUNT) {
-			if (adapter->cache_sta_info[i].in_use != TRUE)
-				break;
+	cache_sta_info =
+		hdd_get_sta_info_by_mac(&adapter->cache_sta_info_list,
+					event->staMac.bytes);
 
-			if (adapter->cache_sta_info[i].disassoc_ts &&
-			    (!oldest_disassoc_sta_ts ||
-			    (qdf_system_time_after(
-					oldest_disassoc_sta_ts,
-					adapter->
-					cache_sta_info[i].disassoc_ts)))) {
-				oldest_disassoc_sta_ts =
-					adapter->
-						cache_sta_info[i].disassoc_ts;
-				oldest_disassoc_sta_idx = i;
-			}
-			i++;
-		}
-	}
+	if (!cache_sta_info) {
+		cache_sta_info = qdf_mem_malloc(sizeof(*cache_sta_info));
+		if (!cache_sta_info)
+			return;
 
-	if ((i == WLAN_MAX_STA_COUNT) && oldest_disassoc_sta_ts) {
-		hdd_debug("reached max cached sta_id, removing oldest stainfo");
-		i = oldest_disassoc_sta_idx;
-	}
-	if (i < WLAN_MAX_STA_COUNT) {
-		qdf_mem_zero(&adapter->cache_sta_info[i],
-			     sizeof(*stainfo));
-		qdf_mem_copy(&adapter->cache_sta_info[i],
-				     stainfo, sizeof(struct hdd_station_info));
+		qdf_mem_copy(cache_sta_info, stainfo, sizeof(*cache_sta_info));
+		qdf_mem_zero(&cache_sta_info->sta_node,
+			     sizeof(cache_sta_info->sta_node));
 
-	} else {
-		hdd_debug("reached max sta_id, stainfo can't be cached");
+		/*
+		 * If cache_sta_info is not present and cache limit is not
+		 * reached, then create and attach. Else find the cache that is
+		 * the oldest and replace that with the new cache.
+		 */
+		if (qdf_atomic_read(&adapter->cache_sta_count) <
+		    WLAN_MAX_STA_COUNT) {
+			hdd_sta_info_attach(&adapter->cache_sta_info_list,
+					    cache_sta_info);
+			qdf_atomic_inc(&adapter->cache_sta_count);
+		} else {
+			struct hdd_station_info *temp_sta_info;
+
+			hdd_debug("reached max caching, removing oldest");
+
+			/* Find the oldest cached station */
+			hdd_for_each_station(adapter->cache_sta_info_list,
+					     temp_sta_info, index) {
+				if (temp_sta_info->disassoc_ts &&
+				    (!oldest_disassoc_sta_ts ||
+				    qdf_system_time_after(
+				    oldest_disassoc_sta_ts,
+				    temp_sta_info->disassoc_ts))) {
+					oldest_disassoc_sta_ts =
+						temp_sta_info->disassoc_ts;
+					oldest_disassoc_sta_info =
+						temp_sta_info;
+				}
+			}
+
+			/* Remove the oldest and store the current */
+			hdd_sta_info_detach(&adapter->cache_sta_info_list,
+					    oldest_disassoc_sta_info);
+			hdd_sta_info_attach(&adapter->cache_sta_info_list,
+					    cache_sta_info);
+		}
 	}
 
 	hdd_debug("cap %d %d %d %d %d %d %d %d %d %x %d",
@@ -2323,8 +2328,9 @@ QDF_STATUS hdd_hostapd_sap_event_cb(struct sap_event *sap_event,
 		memcpy(wrqu.addr.sa_data,
 		       &disassoc_comp->staMac, QDF_MAC_ADDR_SIZE);
 
-		cache_stainfo = hdd_get_stainfo(adapter->cache_sta_info,
-						disassoc_comp->staMac);
+		cache_stainfo = hdd_get_sta_info_by_mac(
+						&adapter->cache_sta_info_list,
+						disassoc_comp->staMac.bytes);
 		if (cache_stainfo) {
 			/* Cache the disassoc info */
 			cache_stainfo->rssi = disassoc_comp->rssi;
@@ -3353,6 +3359,9 @@ QDF_STATUS hdd_init_ap_mode(struct hdd_adapter *adapter, bool reinit)
 	/* Register as a wireless device */
 	hdd_register_hostapd_wext(adapter->dev);
 
+	/* Cache station count initialize to zero */
+	qdf_atomic_init(&adapter->cache_sta_count);
+
 	/* Initialize the data path module */
 	hdd_softap_init_tx_rx(adapter);
 
@@ -3362,6 +3371,12 @@ QDF_STATUS hdd_init_ap_mode(struct hdd_adapter *adapter, bool reinit)
 		goto error_release_softap_tx_rx;
 	}
 
+	status = hdd_sta_info_init(&adapter->cache_sta_info_list);
+	if (QDF_IS_STATUS_ERROR(status)) {
+		hdd_err("cache sta info init failed");
+		goto error_release_sta_info;
+	}
+
 	status = hdd_wmm_adapter_init(adapter);
 	if (!QDF_IS_STATUS_SUCCESS(status)) {
 		hdd_err("hdd_wmm_adapter_init() failed code: %08d [x%08x]",
@@ -3402,6 +3417,8 @@ QDF_STATUS hdd_init_ap_mode(struct hdd_adapter *adapter, bool reinit)
 	return status;
 
 error_release_wmm:
+	hdd_sta_info_deinit(&adapter->cache_sta_info_list);
+error_release_sta_info:
 	hdd_sta_info_deinit(&adapter->sta_info_list);
 error_release_softap_tx_rx:
 	hdd_softap_deinit_tx_rx(adapter);

core/hdd/src/wlan_hdd_main.c

@@ -4233,6 +4233,9 @@ hdd_alloc_station_adapter(struct hdd_context *hdd_ctx, tSirMacAddr mac_addr,
 	adapter->disconnection_in_progress = false;
 	adapter->send_mode_change = true;
 
+	/* Cache station count initialize to zero */
+	qdf_atomic_init(&adapter->cache_sta_count);
+
 	/* Init the net_device structure */
 	strlcpy(dev->name, name, IFNAMSIZ);
 
@@ -4856,8 +4859,10 @@ static void hdd_cleanup_adapter(struct hdd_context *hdd_ctx,
 	qdf_spinlock_destroy(&adapter->vdev_lock);
 
 	if (adapter->device_mode == QDF_SAP_MODE ||
-	    adapter->device_mode == QDF_P2P_GO_MODE)
+	    adapter->device_mode == QDF_P2P_GO_MODE) {
 		hdd_sta_info_deinit(&adapter->sta_info_list);
+		hdd_sta_info_deinit(&adapter->cache_sta_info_list);
+	}
 
 	wlan_hdd_debugfs_csr_deinit(adapter);
 	if (adapter->device_mode == QDF_STA_MODE)
@@ -6048,6 +6053,9 @@ QDF_STATUS hdd_stop_adapter(struct hdd_context *hdd_ctx,
 		qdf_mem_free(adapter->session.ap.beacon);
 		adapter->session.ap.beacon = NULL;
 
+		/* Clear all the cached sta info */
+		hdd_clear_cached_sta_info(&adapter->cache_sta_info_list);
+
 		/*
 		 * If Do_Not_Break_Stream was enabled clear avoid channel list.
 		 */
@@ -6321,8 +6329,10 @@ QDF_STATUS hdd_reset_all_adapters(struct hdd_context *hdd_ctx)
 
 		hdd_softap_deinit_tx_rx(adapter);
 		if (adapter->device_mode == QDF_SAP_MODE ||
-		    adapter->device_mode == QDF_P2P_GO_MODE)
+		    adapter->device_mode == QDF_P2P_GO_MODE) {
 			hdd_sta_info_deinit(&adapter->sta_info_list);
+			hdd_sta_info_deinit(&adapter->cache_sta_info_list);
+		}
 
 		hdd_deregister_hl_netdev_fc_timer(adapter);
 		hdd_deregister_tx_flow_control(adapter);

core/hdd/src/wlan_hdd_sta_info.c

@@ -116,3 +116,22 @@ struct hdd_station_info *hdd_get_sta_info_by_mac(
 
 	return NULL;
 }
+
+void hdd_clear_cached_sta_info(struct hdd_sta_info_obj *sta_info_container)
+{
+	struct hdd_station_info *sta_info = NULL;
+	uint8_t index = 0;
+	struct qdf_ht_entry *tmp;
+
+	if (!sta_info_container) {
+		hdd_err("Parameter null");
+		return;
+	}
+
+	qdf_ht_for_each_safe(sta_info_container->sta_obj, index, tmp, sta_info,
+			     sta_node) {
+		if (sta_info) {
+			hdd_sta_info_detach(sta_info_container, sta_info);
+		}
+	}
+}

core/hdd/src/wlan_hdd_sta_info.h

@@ -266,5 +266,13 @@ QDF_STATUS hdd_sta_info_attach(struct hdd_sta_info_obj *sta_info_container,
 struct hdd_station_info *hdd_get_sta_info_by_mac(
 				struct hdd_sta_info_obj *sta_info_container,
 				const uint8_t *mac_addr);
+/**
+ * hdd_clear_cached_sta_info() - Clear the cached sta info from the container
+ * @sta_info_container: The station info container obj that stores and maintains
+ *                      the sta_info obj.
+ *
+ * Return: None
+ */
+void hdd_clear_cached_sta_info(struct hdd_sta_info_obj *sta_info_container);
 
 #endif /* __WLAN_HDD_STA_INFO_H */

core/hdd/src/wlan_hdd_station_info.c

@@ -996,13 +996,14 @@ static int hdd_get_cached_station_remote(struct hdd_context *hdd_ctx,
 					 struct hdd_adapter *adapter,
 					 struct qdf_mac_addr mac_addr)
 {
-	struct hdd_station_info *stainfo = hdd_get_stainfo(
-						adapter->cache_sta_info,
-						mac_addr);
+	struct hdd_station_info *stainfo;
 	struct sk_buff *skb = NULL;
 	uint32_t nl_buf_len = NLMSG_HDRLEN;
 	uint8_t channel_width;
 
+	stainfo = hdd_get_sta_info_by_mac(&adapter->cache_sta_info_list,
+					   mac_addr.bytes);
+
 	if (!stainfo) {
 		hdd_err("peer " QDF_MAC_ADDR_STR " not found",
 			QDF_MAC_ADDR_ARRAY(mac_addr.bytes));
@@ -1081,7 +1082,8 @@ static int hdd_get_cached_station_remote(struct hdd_context *hdd_ctx,
 		}
 	}
 
-	qdf_mem_zero(stainfo, sizeof(*stainfo));
+	hdd_sta_info_detach(&adapter->cache_sta_info_list, stainfo);
+	qdf_atomic_dec(&adapter->cache_sta_count);
 
 	return cfg80211_vendor_cmd_reply(skb);
 fail: