+static void ieee80211_set_default_queues(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_local *local = sdata->local;
+ int i;
+
+ for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+ if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
+ sdata->vif.hw_queue[i] = IEEE80211_INVAL_HW_QUEUE;
+ else
+ sdata->vif.hw_queue[i] = i;
+ }
+ sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
+}
+
+static int ieee80211_add_virtual_monitor(struct ieee80211_local *local)
+{
+ struct ieee80211_sub_if_data *sdata;
+ int ret;
+
+ if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
+ return 0;
+
+ if (local->monitor_sdata)
+ return 0;
+
+ sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size, GFP_KERNEL);
+ if (!sdata)
+ return -ENOMEM;
+
+ /* set up data */
+ sdata->local = local;
+ sdata->vif.type = NL80211_IFTYPE_MONITOR;
+ snprintf(sdata->name, IFNAMSIZ, "%s-monitor",
+ wiphy_name(local->hw.wiphy));
+
+ ieee80211_set_default_queues(sdata);
+
+ ret = drv_add_interface(local, sdata);
+ if (WARN_ON(ret)) {
+ /* ok .. stupid driver, it asked for this! */
+ kfree(sdata);
+ return ret;
+ }
+
+ ret = ieee80211_check_queues(sdata);
+ if (ret) {
+ kfree(sdata);
+ return ret;
+ }
+
+ rcu_assign_pointer(local->monitor_sdata, sdata);
+
+ return 0;
+}
+
+static void ieee80211_del_virtual_monitor(struct ieee80211_local *local)
+{
+ struct ieee80211_sub_if_data *sdata;
+
+ if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
+ return;
+
+ sdata = rtnl_dereference(local->monitor_sdata);
+
+ if (!sdata)
+ return;
+
+ rcu_assign_pointer(local->monitor_sdata, NULL);
+ synchronize_net();
+
+ drv_remove_interface(local, sdata);
+
+ kfree(sdata);
+}
+