mac80211: track beacons separately from the rx path activity

Separate beacon and rx path tracking in preparation for the beacon filtering
support. At the same time change ieee80211_associated() to look a bit simpler.

Probe requests are now sent only after IEEE80211_PROBE_IDLE_TIME, which
is now set to 60 seconds.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 52 insertions, 32 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 055bb776408c..8a617a7fc090 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -308,6 +308,7 @@ struct ieee80211_if_managed {
         unsigned long request;
 
         unsigned long last_probe;
+        unsigned long last_beacon;
 
         unsigned int flags;
 
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 209abb073dfb..8f30f4d19da0 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -30,7 +30,7 @@
 #define IEEE80211_ASSOC_TIMEOUT (HZ / 5)
 #define IEEE80211_ASSOC_MAX_TRIES 3
 #define IEEE80211_MONITORING_INTERVAL (2 * HZ)
-#define IEEE80211_PROBE_INTERVAL (60 * HZ)
+#define IEEE80211_PROBE_IDLE_TIME (60 * HZ)
 #define IEEE80211_RETRY_AUTH_INTERVAL (1 * HZ)
 
 /* utils */
@@ -930,7 +930,7 @@ static void ieee80211_associated(struct ieee80211_sub_if_data *sdata)
         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
         struct ieee80211_local *local = sdata->local;
         struct sta_info *sta;
-        int disassoc;
+        bool disassoc = false;
 
         /* TODO: start monitoring current AP signal quality and number of
          * missed beacons. Scan other channels every now and then and search
@@ -945,36 +945,39 @@ static void ieee80211_associated(struct ieee80211_sub_if_data *sdata)
         if (!sta) {
                 printk(KERN_DEBUG "%s: No STA entry for own AP %pM\n",
                        sdata->dev->name, ifmgd->bssid);
-                disassoc = 1;
-        } else {
-                disassoc = 0;
-                if (time_after(jiffies,
-                               sta->last_rx + IEEE80211_MONITORING_INTERVAL)) {
-                        if (ifmgd->flags & IEEE80211_STA_PROBEREQ_POLL) {
-                                printk(KERN_DEBUG "%s: No ProbeResp from "
-                                       "current AP %pM - assume out of "
-                                       "range\n",
-                                       sdata->dev->name, ifmgd->bssid);
-                                disassoc = 1;
-                        } else
-                                ieee80211_send_probe_req(sdata, ifmgd->bssid,
-                                                         ifmgd->ssid,
-                                                         ifmgd->ssid_len,
-                                                         NULL, 0);
-                        ifmgd->flags ^= IEEE80211_STA_PROBEREQ_POLL;
-                } else {
-                        ifmgd->flags &= ~IEEE80211_STA_PROBEREQ_POLL;
-                        if (time_after(jiffies, ifmgd->last_probe +
-                                       IEEE80211_PROBE_INTERVAL)) {
-                                ifmgd->last_probe = jiffies;
-                                ieee80211_send_probe_req(sdata, ifmgd->bssid,
-                                                         ifmgd->ssid,
-                                                         ifmgd->ssid_len,
-                                                         NULL, 0);
-                        }
-                }
+                disassoc = true;
+                goto unlock;
+        }
+
+        if ((ifmgd->flags & IEEE80211_STA_PROBEREQ_POLL) &&
+            time_after(jiffies, sta->last_rx + IEEE80211_MONITORING_INTERVAL)) {
+                printk(KERN_DEBUG "%s: no probe response from AP %pM "
+                       "- disassociating\n",
+                       sdata->dev->name, ifmgd->bssid);
+                disassoc = true;
+                ifmgd->flags &= ~IEEE80211_STA_PROBEREQ_POLL;
+                goto unlock;
+        }
+
+        if (time_after(jiffies,
+                       ifmgd->last_beacon + IEEE80211_MONITORING_INTERVAL)) {
+                printk(KERN_DEBUG "%s: beacon loss from AP %pM "
+                       "- sending probe request\n",
+                       sdata->dev->name, ifmgd->bssid);
+                ifmgd->flags |= IEEE80211_STA_PROBEREQ_POLL;
+                ieee80211_send_probe_req(sdata, ifmgd->bssid, ifmgd->ssid,
+                                         ifmgd->ssid_len, NULL, 0);
+                goto unlock;
+
+        }
+
+        if (time_after(jiffies, sta->last_rx + IEEE80211_PROBE_IDLE_TIME)) {
+                ifmgd->flags |= IEEE80211_STA_PROBEREQ_POLL;
+                ieee80211_send_probe_req(sdata, ifmgd->bssid, ifmgd->ssid,
+                                         ifmgd->ssid_len, NULL, 0);
         }
 
+ unlock:
         rcu_read_unlock();
 
         if (disassoc)
@@ -1374,6 +1377,12 @@ static void ieee80211_rx_mgmt_assoc_resp(struct ieee80211_sub_if_data *sdata,
         bss_conf->assoc_capability = capab_info;
         ieee80211_set_associated(sdata, changed);
 
+        /*
+         * initialise the time of last beacon to be the association time,
+         * otherwise beacon loss check will trigger immediately
+         */
+        ifmgd->last_beacon = jiffies;
+
         ieee80211_associated(sdata);
         cfg80211_send_rx_assoc(sdata->dev, (u8 *) mgmt, len);
 }
@@ -1422,9 +1431,12 @@ static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
                                          size_t len,
                                          struct ieee80211_rx_status *rx_status)
 {
+        struct ieee80211_if_managed *ifmgd;
         size_t baselen;
         struct ieee802_11_elems elems;
 
+        ifmgd = &sdata->u.mgd;
+
         if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
                 return; /* ignore ProbeResp to foreign address */
 
@@ -1439,11 +1451,14 @@ static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
 
         /* direct probe may be part of the association flow */
         if (test_and_clear_bit(IEEE80211_STA_REQ_DIRECT_PROBE,
-            &sdata->u.mgd.request)) {
+                               &ifmgd->request)) {
                 printk(KERN_DEBUG "%s direct probe responded\n",
                        sdata->dev->name);
                 ieee80211_authenticate(sdata);
         }
+
+        if (ifmgd->flags & IEEE80211_STA_PROBEREQ_POLL)
+                ifmgd->flags &= ~IEEE80211_STA_PROBEREQ_POLL;
 }
 
 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index dbfb28465354..eff59f36e8eb 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -850,7 +850,11 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
                  * Mesh beacons will update last_rx when if they are found to
                  * match the current local configuration when processed.
                  */
-                sta->last_rx = jiffies;
+                if (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
+                    ieee80211_is_beacon(hdr->frame_control)) {
+                        rx->sdata->u.mgd.last_beacon = jiffies;
+                } else
+                        sta->last_rx = jiffies;
         }
 
         if (!(rx->flags & IEEE80211_RX_RA_MATCH))