1 files changed, 112 insertions, 31 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index a3a9421555af..794807914940 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -28,13 +28,19 @@
 #include "rate.h"
 #include "led.h"
 
+#define IEEE80211_MAX_NULLFUNC_TRIES 2
 #define IEEE80211_MAX_PROBE_TRIES 5
 
 /*
- * beacon loss detection timeout
- * XXX: should depend on beacon interval
+ * Beacon loss timeout is calculated as N frames times the
+ * advertised beacon interval.  This may need to be somewhat
+ * higher than what hardware might detect to account for
+ * delays in the host processing frames. But since we also
+ * probe on beacon miss before declaring the connection lost
+ * default to what we want.
  */
-#define IEEE80211_BEACON_LOSS_TIME      (2 * HZ)
+#define IEEE80211_BEACON_LOSS_COUNT     7
+
 /*
  * Time the connection can be idle before we probe
  * it to see if we can still talk to the AP.
@@ -121,7 +127,7 @@ void ieee80211_sta_reset_beacon_monitor(struct ieee80211_sub_if_data *sdata)
                 return;
 
         mod_timer(&sdata->u.mgd.bcn_mon_timer,
-                  round_jiffies_up(jiffies + IEEE80211_BEACON_LOSS_TIME));
+                  round_jiffies_up(jiffies + sdata->u.mgd.beacon_timeout));
 }
 
 void ieee80211_sta_reset_conn_monitor(struct ieee80211_sub_if_data *sdata)
@@ -871,6 +877,9 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
         bss_info_changed |= ieee80211_handle_bss_capability(sdata,
                 cbss->capability, bss->has_erp_value, bss->erp_value);
 
+        sdata->u.mgd.beacon_timeout = usecs_to_jiffies(ieee80211_tu_to_usec(
+                IEEE80211_BEACON_LOSS_COUNT * bss_conf->beacon_int));
+
         sdata->u.mgd.associated = cbss;
         memcpy(sdata->u.mgd.bssid, cbss->bssid, ETH_ALEN);
 
@@ -1026,6 +1035,51 @@ void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,
         ieee80211_sta_reset_conn_monitor(sdata);
 }
 
+static void ieee80211_reset_ap_probe(struct ieee80211_sub_if_data *sdata)
+{
+        struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+
+        if (!(ifmgd->flags & (IEEE80211_STA_BEACON_POLL |
+                              IEEE80211_STA_CONNECTION_POLL)))
+            return;
+
+        ifmgd->flags &= ~(IEEE80211_STA_CONNECTION_POLL |
+                          IEEE80211_STA_BEACON_POLL);
+        mutex_lock(&sdata->local->iflist_mtx);
+        ieee80211_recalc_ps(sdata->local, -1);
+        mutex_unlock(&sdata->local->iflist_mtx);
+
+        if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR)
+                return;
+
+        /*
+         * We've received a probe response, but are not sure whether
+         * we have or will be receiving any beacons or data, so let's
+         * schedule the timers again, just in case.
+         */
+        ieee80211_sta_reset_beacon_monitor(sdata);
+
+        mod_timer(&ifmgd->conn_mon_timer,
+                  round_jiffies_up(jiffies +
+                                   IEEE80211_CONNECTION_IDLE_TIME));
+}
+
+void ieee80211_sta_tx_notify(struct ieee80211_sub_if_data *sdata,
+                             struct ieee80211_hdr *hdr)
+{
+        if (!ieee80211_is_data(hdr->frame_control) &&
+            !ieee80211_is_nullfunc(hdr->frame_control))
+            return;
+
+        ieee80211_sta_reset_conn_monitor(sdata);
+
+        if (ieee80211_is_nullfunc(hdr->frame_control) &&
+            sdata->u.mgd.probe_send_count > 0) {
+                sdata->u.mgd.probe_send_count = 0;
+                ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+        }
+}
+
 static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
@@ -1041,8 +1095,19 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
         if (ifmgd->probe_send_count >= unicast_limit)
                 dst = NULL;
 
-        ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
-        ieee80211_send_probe_req(sdata, dst, ssid + 2, ssid[1], NULL, 0);
+        /*
+         * When the hardware reports an accurate Tx ACK status, it's
+         * better to send a nullfunc frame instead of a probe request,
+         * as it will kick us off the AP quickly if we aren't associated
+         * anymore. The timeout will be reset if the frame is ACKed by
+         * the AP.
+         */
+        if (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)
+                ieee80211_send_nullfunc(sdata->local, sdata, 0);
+        else {
+                ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
+                ieee80211_send_probe_req(sdata, dst, ssid + 2, ssid[1], NULL, 0);
+        }
 
         ifmgd->probe_send_count++;
         ifmgd->probe_timeout = jiffies + IEEE80211_PROBE_WAIT;
@@ -1108,6 +1173,30 @@ static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata,
         mutex_unlock(&ifmgd->mtx);
 }
 
+struct sk_buff *ieee80211_ap_probereq_get(struct ieee80211_hw *hw,
+                                          struct ieee80211_vif *vif)
+{
+        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
+        struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+        struct sk_buff *skb;
+        const u8 *ssid;
+
+        if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION))
+                return NULL;
+
+        ASSERT_MGD_MTX(ifmgd);
+
+        if (!ifmgd->associated)
+                return NULL;
+
+        ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
+        skb = ieee80211_build_probe_req(sdata, ifmgd->associated->bssid,
+                                        ssid + 2, ssid[1], NULL, 0);
+
+        return skb;
+}
+EXPORT_SYMBOL(ieee80211_ap_probereq_get);
+
 static void __ieee80211_connection_loss(struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
@@ -1485,29 +1574,8 @@ static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
 
         if (ifmgd->associated &&
-            memcmp(mgmt->bssid, ifmgd->associated->bssid, ETH_ALEN) == 0 &&
-            ifmgd->flags & (IEEE80211_STA_BEACON_POLL |
-                            IEEE80211_STA_CONNECTION_POLL)) {
-                ifmgd->flags &= ~(IEEE80211_STA_CONNECTION_POLL |
-                                  IEEE80211_STA_BEACON_POLL);
-                mutex_lock(&sdata->local->iflist_mtx);
-                ieee80211_recalc_ps(sdata->local, -1);
-                mutex_unlock(&sdata->local->iflist_mtx);
-
-                if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR)
-                        return;
-
-                /*
-                 * We've received a probe response, but are not sure whether
-                 * we have or will be receiving any beacons or data, so let's
-                 * schedule the timers again, just in case.
-                 */
-                ieee80211_sta_reset_beacon_monitor(sdata);
-
-                mod_timer(&ifmgd->conn_mon_timer,
-                          round_jiffies_up(jiffies +
-                                           IEEE80211_CONNECTION_IDLE_TIME));
-        }
+            memcmp(mgmt->bssid, ifmgd->associated->bssid, ETH_ALEN) == 0)
+                ieee80211_reset_ap_probe(sdata);
 }
 
 /*
@@ -1857,12 +1925,23 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
                             IEEE80211_STA_CONNECTION_POLL) &&
             ifmgd->associated) {
                 u8 bssid[ETH_ALEN];
+                int max_tries;
 
                 memcpy(bssid, ifmgd->associated->bssid, ETH_ALEN);
-                if (time_is_after_jiffies(ifmgd->probe_timeout))
+
+                if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)
+                        max_tries = IEEE80211_MAX_NULLFUNC_TRIES;
+                else
+                        max_tries = IEEE80211_MAX_PROBE_TRIES;
+
+                /* ACK received for nullfunc probing frame */
+                if (!ifmgd->probe_send_count)
+                        ieee80211_reset_ap_probe(sdata);
+
+                else if (time_is_after_jiffies(ifmgd->probe_timeout))
                         run_again(ifmgd, ifmgd->probe_timeout);
 
-                else if (ifmgd->probe_send_count < IEEE80211_MAX_PROBE_TRIES) {
+                else if (ifmgd->probe_send_count < max_tries) {
 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
                         wiphy_debug(local->hw.wiphy,
                                     "%s: No probe response from AP %pM"
@@ -1988,6 +2067,8 @@ void ieee80211_sta_restart(struct ieee80211_sub_if_data *sdata)
                 add_timer(&ifmgd->timer);
         if (test_and_clear_bit(TMR_RUNNING_CHANSW, &ifmgd->timers_running))
                 add_timer(&ifmgd->chswitch_timer);
+        ieee80211_sta_reset_beacon_monitor(sdata);
+        ieee80211_restart_sta_timer(sdata);
 }
 #endif