mac80211: remove ARP filter enable/disable logic

Depending on the driver, having ARP filtering for
some addresses may be possible. Remove the logic
that tracks whether ARP filter is enabled or not
and give the driver the total number of addresses
instead of the length of the list so it can make
its own decision.

Reviewed-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c

@@ -539,9 +539,8 @@ brcms_ops_bss_info_changed(struct ieee80211_hw *hw,
 
 	if (changed & BSS_CHANGED_ARP_FILTER) {
 		/* Hardware ARP filter address list or state changed */
-		brcms_err(core, "%s: arp filtering: enabled %s, count %d"
-			  " (implement)\n", __func__, info->arp_filter_enabled ?
-			  "true" : "false", info->arp_addr_cnt);
+		brcms_err(core, "%s: arp filtering: %d addresses"
+			  " (implement)\n", __func__, info->arp_addr_cnt);
 	}
 
 	if (changed & BSS_CHANGED_QOS) {

drivers/net/wireless/ti/wlcore/main.c

@@ -4113,8 +4113,7 @@ sta_not_found:
 		wlvif->sta.qos = bss_conf->qos;
 		WARN_ON(wlvif->bss_type != BSS_TYPE_STA_BSS);
 
-		if (bss_conf->arp_addr_cnt == 1 &&
-		    bss_conf->arp_filter_enabled) {
+		if (bss_conf->arp_addr_cnt == 1 && bss_conf->assoc) {
 			wlvif->ip_addr = addr;
 			/*
 			 * The template should have been configured only upon

include/net/mac80211.h

@@ -297,11 +297,9 @@ enum ieee80211_rssi_event {
  *	may filter ARP queries targeted for other addresses than listed here.
  *	The driver must allow ARP queries targeted for all address listed here
  *	to pass through. An empty list implies no ARP queries need to pass.
- * @arp_addr_cnt: Number of addresses currently on the list.
- * @arp_filter_enabled: Enable ARP filtering - if enabled, the hardware may
- *	filter ARP queries based on the @arp_addr_list, if disabled, the
- *	hardware must not perform any ARP filtering. Note, that the filter will
- *	be enabled also in promiscuous mode.
+ * @arp_addr_cnt: Number of addresses currently on the list. Note that this
+ *	may be larger than %IEEE80211_BSS_ARP_ADDR_LIST_LEN (the arp_addr_list
+ *	array size), it's up to the driver what to do in that case.
  * @qos: This is a QoS-enabled BSS.
  * @idle: This interface is idle. There's also a global idle flag in the
  *	hardware config which may be more appropriate depending on what
@@ -338,8 +336,7 @@ struct ieee80211_bss_conf {
 	u32 cqm_rssi_hyst;
 	struct cfg80211_chan_def chandef;
 	__be32 arp_addr_list[IEEE80211_BSS_ARP_ADDR_LIST_LEN];
-	u8 arp_addr_cnt;
-	bool arp_filter_enabled;
+	int arp_addr_cnt;
 	bool qos;
 	bool idle;
 	bool ps;

net/mac80211/ieee80211_i.h

@@ -747,8 +747,6 @@ struct ieee80211_sub_if_data {
 	struct work_struct work;
 	struct sk_buff_head skb_queue;
 
-	bool arp_filter_state;
-
 	u8 needed_rx_chains;
 	enum ieee80211_smps_mode smps_mode;
 

net/mac80211/iface.c

@@ -1574,9 +1574,6 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 	/* initialise type-independent data */
 	sdata->wdev.wiphy = local->hw.wiphy;
 	sdata->local = local;
-#ifdef CONFIG_INET
-	sdata->arp_filter_state = true;
-#endif
 
 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
 		skb_queue_head_init(&sdata->fragments[i].skb_list);

net/mac80211/main.c

@@ -349,27 +349,19 @@ static int ieee80211_ifa_changed(struct notifier_block *nb,
 
 	/* Copy the addresses to the bss_conf list */
 	ifa = idev->ifa_list;
-	while (c < IEEE80211_BSS_ARP_ADDR_LIST_LEN && ifa) {
-		bss_conf->arp_addr_list[c] = ifa->ifa_address;
+	while (ifa) {
+		if (c < IEEE80211_BSS_ARP_ADDR_LIST_LEN)
+			bss_conf->arp_addr_list[c] = ifa->ifa_address;
 		ifa = ifa->ifa_next;
 		c++;
 	}
 
-	/* If not all addresses fit the list, disable filtering */
-	if (ifa) {
-		sdata->arp_filter_state = false;
-		c = 0;
-	} else {
-		sdata->arp_filter_state = true;
-	}
 	bss_conf->arp_addr_cnt = c;
 
 	/* Configure driver only if associated (which also implies it is up) */
-	if (ifmgd->associated) {
-		bss_conf->arp_filter_enabled = sdata->arp_filter_state;
+	if (ifmgd->associated)
 		ieee80211_bss_info_change_notify(sdata,
 						 BSS_CHANGED_ARP_FILTER);
-	}
 
 	mutex_unlock(&ifmgd->mtx);
 

net/mac80211/mlme.c

@@ -1465,10 +1465,8 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
 		bss_info_changed |= BSS_CHANGED_CQM;
 
 	/* Enable ARP filtering */
-	if (bss_conf->arp_filter_enabled != sdata->arp_filter_state) {
-		bss_conf->arp_filter_enabled = sdata->arp_filter_state;
+	if (bss_conf->arp_addr_cnt)
 		bss_info_changed |= BSS_CHANGED_ARP_FILTER;
-	}
 
 	ieee80211_bss_info_change_notify(sdata, bss_info_changed);
 
@@ -1582,10 +1580,8 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 	cancel_work_sync(&local->dynamic_ps_enable_work);
 
 	/* Disable ARP filtering */
-	if (sdata->vif.bss_conf.arp_filter_enabled) {
-		sdata->vif.bss_conf.arp_filter_enabled = false;
+	if (sdata->vif.bss_conf.arp_addr_cnt)
 		changed |= BSS_CHANGED_ARP_FILTER;
-	}
 
 	sdata->vif.bss_conf.qos = false;
 	changed |= BSS_CHANGED_QOS;

net/mac80211/trace.h

@@ -347,8 +347,11 @@ TRACE_EVENT(drv_bss_info_changed,
 		__field(s32, cqm_rssi_hyst);
 		__field(u32, channel_width);
 		__field(u32, channel_cfreq1);
-		__dynamic_array(u32, arp_addr_list, info->arp_addr_cnt);
-		__field(bool, arp_filter_enabled);
+		__dynamic_array(u32, arp_addr_list,
+				info->arp_addr_cnt > IEEE80211_BSS_ARP_ADDR_LIST_LEN ?
+					IEEE80211_BSS_ARP_ADDR_LIST_LEN :
+					info->arp_addr_cnt);
+		__field(int, arp_addr_cnt);
 		__field(bool, qos);
 		__field(bool, idle);
 		__field(bool, ps);
@@ -384,9 +387,11 @@ TRACE_EVENT(drv_bss_info_changed,
 		__entry->cqm_rssi_hyst = info->cqm_rssi_hyst;
 		__entry->channel_width = info->chandef.width;
 		__entry->channel_cfreq1 = info->chandef.center_freq1;
+		__entry->arp_addr_cnt = info->arp_addr_cnt;
 		memcpy(__get_dynamic_array(arp_addr_list), info->arp_addr_list,
-		       sizeof(u32) * info->arp_addr_cnt);
-		__entry->arp_filter_enabled = info->arp_filter_enabled;
+		       sizeof(u32) * (info->arp_addr_cnt > IEEE80211_BSS_ARP_ADDR_LIST_LEN ?
+					IEEE80211_BSS_ARP_ADDR_LIST_LEN :
+					info->arp_addr_cnt));
 		__entry->qos = info->qos;
 		__entry->idle = info->idle;
 		__entry->ps = info->ps;