mac80211: A-MPDU Tx adding basic functionality

This patch adds the following abilities to mac80211:
 - start A-MPDU Tx session
 - stop A-MPDU Tx session
 - call backs to start/stop A-MPDU Tx session
 - sending addBA request
 - processing addBA response

Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 180 insertions, 2 deletions

diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c
index d5d5610db1bd..c4d57346eacf 100644
--- a/net/mac80211/ieee80211_sta.c
+++ b/net/mac80211/ieee80211_sta.c
@@ -1045,6 +1045,58 @@ static void ieee80211_send_addba_resp(struct net_device *dev, u8 *da, u16 tid,
         return;
 }
 
+void ieee80211_send_addba_request(struct net_device *dev, const u8 *da,
+                                u16 tid, u8 dialog_token, u16 start_seq_num,
+                                u16 agg_size, u16 timeout)
+{
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+        struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+        struct sk_buff *skb;
+        struct ieee80211_mgmt *mgmt;
+        u16 capab;
+
+        skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom + 1 +
+                                sizeof(mgmt->u.action.u.addba_req));
+
+
+        if (!skb) {
+                printk(KERN_ERR "%s: failed to allocate buffer "
+                                "for addba request frame\n", dev->name);
+                return;
+        }
+        skb_reserve(skb, local->hw.extra_tx_headroom);
+        mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
+        memset(mgmt, 0, 24);
+        memcpy(mgmt->da, da, ETH_ALEN);
+        memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
+        if (sdata->vif.type == IEEE80211_IF_TYPE_AP)
+                memcpy(mgmt->bssid, dev->dev_addr, ETH_ALEN);
+        else
+                memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
+
+        mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
+                                        IEEE80211_STYPE_ACTION);
+
+        skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
+
+        mgmt->u.action.category = WLAN_CATEGORY_BACK;
+        mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
+
+        mgmt->u.action.u.addba_req.dialog_token = dialog_token;
+        capab = (u16)(1 << 1);          /* bit 1 aggregation policy */
+        capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
+        capab |= (u16)(agg_size << 6);  /* bit 15:6 max size of aggergation */
+
+        mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
+
+        mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
+        mgmt->u.action.u.addba_req.start_seq_num =
+                                        cpu_to_le16(start_seq_num << 4);
+
+        ieee80211_sta_tx(dev, skb, 0);
+}
+
 static void ieee80211_sta_process_addba_request(struct net_device *dev,
                                                 struct ieee80211_mgmt *mgmt,
                                                 size_t len)
@@ -1156,8 +1208,80 @@ end_no_lock:
         sta_info_put(sta);
 }
 
-static void ieee80211_send_delba(struct net_device *dev, const u8 *da, u16 tid,
-                                 u16 initiator, u16 reason_code)
+static void ieee80211_sta_process_addba_resp(struct net_device *dev,
+                                             struct ieee80211_mgmt *mgmt,
+                                             size_t len)
+{
+        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+        struct ieee80211_hw *hw = &local->hw;
+        struct sta_info *sta;
+        u16 capab;
+        u16 tid;
+        u8 *state;
+
+        sta = sta_info_get(local, mgmt->sa);
+        if (!sta)
+                return;
+
+        capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
+        tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
+
+        state = &sta->ampdu_mlme.tid_tx[tid].state;
+
+        spin_lock_bh(&sta->ampdu_mlme.ampdu_tx);
+
+        if (mgmt->u.action.u.addba_resp.dialog_token !=
+                sta->ampdu_mlme.tid_tx[tid].dialog_token) {
+                spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+                printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+                sta_info_put(sta);
+                return;
+        }
+
+        del_timer_sync(&sta->ampdu_mlme.tid_tx[tid].addba_resp_timer);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+        printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+        if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
+                        == WLAN_STATUS_SUCCESS) {
+                if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
+                        spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+                        printk(KERN_DEBUG "state not HT_ADDBA_REQUESTED_MSK:"
+                                "%d\n", *state);
+                        sta_info_put(sta);
+                        return;
+                }
+
+                if (*state & HT_ADDBA_RECEIVED_MSK)
+                        printk(KERN_DEBUG "double addBA response\n");
+
+                *state |= HT_ADDBA_RECEIVED_MSK;
+                sta->ampdu_mlme.tid_tx[tid].addba_req_num = 0;
+
+                if (*state == HT_AGG_STATE_OPERATIONAL) {
+                        printk(KERN_DEBUG "Aggregation on for tid %d \n", tid);
+                        ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
+                }
+
+                spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+                printk(KERN_DEBUG "recipient accepted agg: tid %d \n", tid);
+        } else {
+                printk(KERN_DEBUG "recipient rejected agg: tid %d \n", tid);
+
+                sta->ampdu_mlme.tid_tx[tid].addba_req_num++;
+                /* this will allow the state check in stop_BA_session */
+                *state = HT_AGG_STATE_OPERATIONAL;
+                spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+                ieee80211_stop_tx_ba_session(hw, sta->addr, tid,
+                                             WLAN_BACK_INITIATOR);
+        }
+        sta_info_put(sta);
+}
+
+void ieee80211_send_delba(struct net_device *dev, const u8 *da, u16 tid,
+                          u16 initiator, u16 reason_code)
 {
         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
@@ -1259,6 +1383,7 @@ void ieee80211_sta_stop_rx_ba_session(struct net_device *dev, u8 *ra, u16 tid,
         sta_info_put(sta);
 }
 
+
 static void ieee80211_sta_process_delba(struct net_device *dev,
                         struct ieee80211_mgmt *mgmt, size_t len)
 {
@@ -1290,6 +1415,53 @@ static void ieee80211_sta_process_delba(struct net_device *dev,
 }
 
 /*
+ * After sending add Block Ack request we activated a timer until
+ * add Block Ack response will arrive from the recipient.
+ * If this timer expires sta_addba_resp_timer_expired will be executed.
+ */
+void sta_addba_resp_timer_expired(unsigned long data)
+{
+        /* not an elegant detour, but there is no choice as the timer passes
+         * only one argument, and both sta_info and TID are needed, so init
+         * flow in sta_info_add gives the TID as data, while the timer_to_id
+         * array gives the sta through container_of */
+        u16 tid = *(int *)data;
+        struct sta_info *temp_sta = container_of((void *)data,
+                struct sta_info, timer_to_tid[tid]);
+
+        struct ieee80211_local *local = temp_sta->local;
+        struct ieee80211_hw *hw = &local->hw;
+        struct sta_info *sta;
+        u8 *state;
+
+        sta = sta_info_get(local, temp_sta->addr);
+        if (!sta)
+                return;
+
+        state = &sta->ampdu_mlme.tid_tx[tid].state;
+        /* check if the TID waits for addBA response */
+        spin_lock_bh(&sta->ampdu_mlme.ampdu_tx);
+        if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
+                spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+                *state = HT_AGG_STATE_IDLE;
+                printk(KERN_DEBUG "timer expired on tid %d but we are not "
+                                "expecting addBA response there", tid);
+                goto timer_expired_exit;
+        }
+
+        printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
+
+        /* go through the state check in stop_BA_session */
+        *state = HT_AGG_STATE_OPERATIONAL;
+        spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
+        ieee80211_stop_tx_ba_session(hw, temp_sta->addr, tid,
+                                     WLAN_BACK_INITIATOR);
+
+timer_expired_exit:
+        sta_info_put(sta);
+}
+
+/*
  * After receiving Block Ack Request (BAR) we activated a
  * timer after each frame arrives from the originator.
  * if this timer expires ieee80211_sta_stop_rx_ba_session will be executed.
@@ -2236,6 +2408,12 @@ static void ieee80211_rx_mgmt_action(struct net_device *dev,
                                 break;
                         ieee80211_sta_process_addba_request(dev, mgmt, len);
                         break;
+                case WLAN_ACTION_ADDBA_RESP:
+                        if (len < (IEEE80211_MIN_ACTION_SIZE +
+                                   sizeof(mgmt->u.action.u.addba_resp)))
+                                break;
+                        ieee80211_sta_process_addba_resp(dev, mgmt, len);
+                        break;
                 case WLAN_ACTION_DELBA:
                         if (len < (IEEE80211_MIN_ACTION_SIZE +
                                    sizeof(mgmt->u.action.u.delba)))