mac80211: consolidate TIM handling code

This consolidates all TIM handling code to avoid re-introducing
errors with the bitmap/set_tim order and to reduce code. While
reading the code I noticed a possible problem so I also added
a comment about that.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 61 insertions, 26 deletions

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index a843bb7dd2d3..b31a627ff97f 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -191,6 +191,64 @@ struct sta_info * sta_info_add(struct ieee80211_local *local,
         return sta;
 }
 
+static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
+{
+        /*
+         * This format has been mandated by the IEEE specifications,
+         * so this line may not be changed to use the __set_bit() format.
+         */
+        bss->tim[aid / 8] |= (1 << (aid % 8));
+}
+
+static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
+{
+        /*
+         * This format has been mandated by the IEEE specifications,
+         * so this line may not be changed to use the __clear_bit() format.
+         */
+        bss->tim[aid / 8] &= ~(1 << (aid % 8));
+}
+
+static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss,
+                                   struct sta_info *sta)
+{
+        if (bss)
+                __bss_tim_set(bss, sta->aid);
+        if (sta->local->ops->set_tim)
+                sta->local->ops->set_tim(local_to_hw(sta->local), sta->aid, 1);
+}
+
+void sta_info_set_tim_bit(struct sta_info *sta)
+{
+        struct ieee80211_sub_if_data *sdata;
+
+        sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
+
+        read_lock_bh(&sta->local->sta_lock);
+        __sta_info_set_tim_bit(sdata->bss, sta);
+        read_unlock_bh(&sta->local->sta_lock);
+}
+
+static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss,
+                                     struct sta_info *sta)
+{
+        if (bss)
+                __bss_tim_clear(bss, sta->aid);
+        if (sta->local->ops->set_tim)
+                sta->local->ops->set_tim(local_to_hw(sta->local), sta->aid, 0);
+}
+
+void sta_info_clear_tim_bit(struct sta_info *sta)
+{
+        struct ieee80211_sub_if_data *sdata;
+
+        sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
+
+        read_lock_bh(&sta->local->sta_lock);
+        __sta_info_clear_tim_bit(sdata->bss, sta);
+        read_unlock_bh(&sta->local->sta_lock);
+}
+
 /* Caller must hold local->sta_lock */
 void sta_info_remove(struct sta_info *sta)
 {
@@ -207,10 +265,9 @@ void sta_info_remove(struct sta_info *sta)
                 sta->flags &= ~WLAN_STA_PS;
                 if (sdata->bss)
                         atomic_dec(&sdata->bss->num_sta_ps);
+                __sta_info_clear_tim_bit(sdata->bss, sta);
         }
         local->num_sta--;
-        sta_info_remove_aid_ptr(sta);
-
 }
 
 void sta_info_free(struct sta_info *sta)
@@ -310,13 +367,8 @@ static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
                        "%s)\n", print_mac(mac, sta->addr));
                 dev_kfree_skb(skb);
 
-                if (skb_queue_empty(&sta->ps_tx_buf)) {
-                        if (sdata->bss)
-                                bss_tim_set(sta->local, sdata->bss, sta->aid);
-                        if (sta->local->ops->set_tim)
-                                sta->local->ops->set_tim(local_to_hw(sta->local),
-                                                         sta->aid, 0);
-                }
+                if (skb_queue_empty(&sta->ps_tx_buf))
+                        sta_info_clear_tim_bit(sta);
         }
 }
 
@@ -395,23 +447,6 @@ void sta_info_stop(struct ieee80211_local *local)
         sta_info_flush(local, NULL);
 }
 
-void sta_info_remove_aid_ptr(struct sta_info *sta)
-{
-        struct ieee80211_sub_if_data *sdata;
-
-        if (sta->aid <= 0)
-                return;
-
-        sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
-
-        if (sdata->bss)
-                __bss_tim_clear(sdata->bss, sta->aid);
-        if (sdata->local->ops->set_tim)
-                sdata->local->ops->set_tim(local_to_hw(sdata->local),
-                                          sta->aid, 0);
-}
-
-
 /**
  * sta_info_flush - flush matching STA entries from the STA table
  * @local: local interface data