mac80211: Use suitable semantics for beacon availability indication

Currently beacon availability upon association is marked by have_beacon
flag of assoc_data structure that becomes unavailable when association
completes. However beacon availability indication is required also after
association to inform a driver. Currently dtim_period parameter is used
for this purpose. Move have_beacon flag to another structure, persistant
throughout a interface's life cycle. Use suitable sematics for beacon
availability indication.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
[fix another instance of BSS_CHANGED_DTIM_PERIOD in docs]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 11 insertions, 9 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index aa5cd2e138be..ad9bb9e10cbb 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1360,7 +1360,7 @@ static bool ieee80211_powersave_allowed(struct ieee80211_sub_if_data *sdata)
                           IEEE80211_STA_CONNECTION_POLL))
                 return false;
 
-        if (!sdata->vif.bss_conf.dtim_period)
+        if (!mgd->have_beacon)
                 return false;
 
         rcu_read_lock();
@@ -1771,7 +1771,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
 
         ieee80211_led_assoc(local, 1);
 
-        if (sdata->u.mgd.assoc_data->have_beacon) {
+        if (sdata->u.mgd.have_beacon) {
                 /*
                  * If the AP is buggy we may get here with no DTIM period
                  * known, so assume it's 1 which is the only safe assumption
@@ -1779,7 +1779,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
                  * probably just won't work at all.
                  */
                 bss_conf->dtim_period = sdata->u.mgd.dtim_period ?: 1;
-                bss_info_changed |= BSS_CHANGED_DTIM_PERIOD;
+                bss_info_changed |= BSS_CHANGED_BEACON_INFO;
         } else {
                 bss_conf->dtim_period = 0;
         }
@@ -1903,6 +1903,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
         del_timer_sync(&sdata->u.mgd.chswitch_timer);
 
         sdata->vif.bss_conf.dtim_period = 0;
+        ifmgd->have_beacon = false;
 
         ifmgd->flags = 0;
         ieee80211_vif_release_channel(sdata);
@@ -2877,7 +2878,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                         const struct ieee80211_tim_ie *tim_ie = elems.tim;
                         ifmgd->dtim_period = tim_ie->dtim_period;
                 }
-                ifmgd->assoc_data->have_beacon = true;
+                ifmgd->have_beacon = true;
                 ifmgd->assoc_data->need_beacon = false;
                 if (local->hw.flags & IEEE80211_HW_TIMING_BEACON_ONLY) {
                         sdata->vif.bss_conf.sync_tsf =
@@ -3059,7 +3060,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
          * If we haven't had a beacon before, tell the driver about the
          * DTIM period (and beacon timing if desired) now.
          */
-        if (!bss_conf->dtim_period) {
+        if (!ifmgd->have_beacon) {
                 /* a few bogus AP send dtim_period = 0 or no TIM IE */
                 if (elems.tim)
                         bss_conf->dtim_period = elems.tim->dtim_period ?: 1;
@@ -3078,7 +3079,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                                 sdata->vif.bss_conf.sync_dtim_count = 0;
                 }
 
-                changed |= BSS_CHANGED_DTIM_PERIOD;
+                changed |= BSS_CHANGED_BEACON_INFO;
+                ifmgd->have_beacon = true;
 
                 mutex_lock(&local->iflist_mtx);
                 ieee80211_recalc_ps(local, -1);
@@ -3424,8 +3426,7 @@ void ieee80211_sta_work(struct ieee80211_sub_if_data *sdata)
 
         if (ifmgd->assoc_data && ifmgd->assoc_data->timeout_started &&
             time_after(jiffies, ifmgd->assoc_data->timeout)) {
-                if ((ifmgd->assoc_data->need_beacon &&
-                     !ifmgd->assoc_data->have_beacon) ||
+                if ((ifmgd->assoc_data->need_beacon && !ifmgd->have_beacon) ||
                     ieee80211_do_assoc(sdata)) {
                         u8 bssid[ETH_ALEN];
 
@@ -4193,6 +4194,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
 
         ifmgd->assoc_data = assoc_data;
         ifmgd->dtim_period = 0;
+        ifmgd->have_beacon = false;
 
         err = ieee80211_prep_connection(sdata, req->bss, true);
         if (err)
@@ -4224,7 +4226,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
                         ifmgd->dtim_period = tim->dtim_period;
                         dtim_count = tim->dtim_count;
                 }
-                assoc_data->have_beacon = true;
+                ifmgd->have_beacon = true;
                 assoc_data->timeout = jiffies;
                 assoc_data->timeout_started = true;