ath9k: avoid retransmitting aggregation frames that a BAR was sent for

The receiver will discard them anyway.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 25 insertions, 3 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 6beaff5e5be..130e5dba955 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -241,6 +241,7 @@ struct ath_atx_tid {
         struct ath_node *an;
         struct ath_atx_ac *ac;
         unsigned long tx_buf[BITS_TO_LONGS(ATH_TID_MAX_BUFS)];
+        int bar_index;
         u16 seq_start;
         u16 seq_next;
         u16 baw_size;
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 8766796b48b..23e80e63bca 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -206,6 +206,8 @@ static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
         while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
                 INCR(tid->seq_start, IEEE80211_SEQ_MAX);
                 INCR(tid->baw_head, ATH_TID_MAX_BUFS);
+                if (tid->bar_index >= 0)
+                        tid->bar_index--;
         }
 }
 
@@ -263,6 +265,7 @@ static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
 
         tid->seq_next = tid->seq_start;
         tid->baw_tail = tid->baw_head;
+        tid->bar_index = -1;
 }
 
 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
@@ -551,8 +554,12 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
                 bf = bf_next;
         }
 
-        if (bar_index >= 0)
+        if (bar_index >= 0) {
+                u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index);
                 ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1));
+                if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq))
+                        tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq);
+        }
 
         /* prepend un-acked frames to the beginning of the pending frame queue */
         if (!skb_queue_empty(&bf_pending)) {
@@ -779,8 +786,6 @@ static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
 
                 bf->bf_state.bf_type = BUF_AMPDU | BUF_AGGR;
                 seqno = bf->bf_state.seqno;
-                if (!bf_first)
-                        bf_first = bf;
 
                 /* do not step over block-ack window */
                 if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno)) {
@@ -788,6 +793,21 @@ static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
                         break;
                 }
 
+                if (tid->bar_index > ATH_BA_INDEX(tid->seq_start, seqno)) {
+                        struct ath_tx_status ts = {};
+                        struct list_head bf_head;
+
+                        INIT_LIST_HEAD(&bf_head);
+                        list_add(&bf->list, &bf_head);
+                        __skb_unlink(skb, &tid->buf_q);
+                        ath_tx_update_baw(sc, tid, seqno);
+                        ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
+                        continue;
+                }
+
+                if (!bf_first)
+                        bf_first = bf;
+
                 if (!rl) {
                         aggr_limit = ath_lookup_rate(sc, bf, tid);
                         rl = 1;
@@ -1130,6 +1150,7 @@ int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
         txtid->state |= AGGR_ADDBA_PROGRESS;
         txtid->paused = true;
         *ssn = txtid->seq_start = txtid->seq_next;
+        txtid->bar_index = -1;
 
         memset(txtid->tx_buf, 0, sizeof(txtid->tx_buf));
         txtid->baw_head = txtid->baw_tail = 0;