ath9k: clean up tx buffer setup

Merge ath_tx_send_normal and ath_tx_send_ht_normal.
Move the paprd state initialization and sequence number assignment
to reduce the number of redundant checks.

This not only simplifies buffer allocation error handling, but also
removes a small inconsistency in the buffer HT flag.
This flag should only be set if the frame is also a QoS data frame.

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

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 32e22677953dff7984fe04b9168cc0416404fe06..8ba0e2d86c1fe7e831829a05bd95426c81d59e4e 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -48,9 +48,9 @@ static u16 bits_per_symbol[][2] = {
 
 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
 
-static void ath_tx_send_ht_normal(struct ath_softc *sc, struct ath_txq *txq,
-                                 struct ath_atx_tid *tid,
-                                 struct list_head *bf_head);
+static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
+                              struct ath_atx_tid *tid,
+                              struct list_head *bf_head);
 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
                                struct ath_txq *txq, struct list_head *bf_q,
                                struct ath_tx_status *ts, int txok, int sendbar);
@@ -160,7 +160,7 @@ static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
                        ath_tx_update_baw(sc, tid, bf->bf_seqno);
                        ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
                } else {
-                       ath_tx_send_ht_normal(sc, txq, tid, &bf_head);
+                       ath_tx_send_normal(sc, txq, tid, &bf_head);
                }
        }
 
@@ -1322,9 +1322,9 @@ static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
        ath_tx_txqaddbuf(sc, txctl->txq, bf_head);
 }
 
-static void ath_tx_send_ht_normal(struct ath_softc *sc, struct ath_txq *txq,
-                                 struct ath_atx_tid *tid,
-                                 struct list_head *bf_head)
+static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
+                              struct ath_atx_tid *tid,
+                              struct list_head *bf_head)
 {
        struct ath_buf *bf;
 
@@ -1332,7 +1332,8 @@ static void ath_tx_send_ht_normal(struct ath_softc *sc, struct ath_txq *txq,
        bf->bf_state.bf_type &= ~BUF_AMPDU;
 
        /* update starting sequence number for subsequent ADDBA request */
-       INCR(tid->seq_start, IEEE80211_SEQ_MAX);
+       if (tid)
+               INCR(tid->seq_start, IEEE80211_SEQ_MAX);
 
        bf->bf_nframes = 1;
        bf->bf_lastbf = bf;
@@ -1341,20 +1342,6 @@ static void ath_tx_send_ht_normal(struct ath_softc *sc, struct ath_txq *txq,
        TX_STAT_INC(txq->axq_qnum, queued);
 }
 
-static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
-                              struct list_head *bf_head)
-{
-       struct ath_buf *bf;
-
-       bf = list_first_entry(bf_head, struct ath_buf, list);
-
-       bf->bf_lastbf = bf;
-       bf->bf_nframes = 1;
-       ath_buf_set_rate(sc, bf);
-       ath_tx_txqaddbuf(sc, txq, bf_head);
-       TX_STAT_INC(txq->axq_qnum, queued);
-}
-
 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
 {
        struct ieee80211_hdr *hdr;
@@ -1411,7 +1398,7 @@ static void assign_aggr_tid_seqno(struct sk_buff *skb,
        INCR(tid->seq_next, IEEE80211_SEQ_MAX);
 }
 
-static int setup_tx_flags(struct sk_buff *skb, bool use_ldpc)
+static int setup_tx_flags(struct sk_buff *skb)
 {
        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
        int flags = 0;
@@ -1422,7 +1409,7 @@ static int setup_tx_flags(struct sk_buff *skb, bool use_ldpc)
        if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
                flags |= ATH9K_TXDESC_NOACK;
 
-       if (use_ldpc)
+       if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
                flags |= ATH9K_TXDESC_LDPC;
 
        return flags;
@@ -1567,18 +1554,24 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf)
                ath9k_hw_set11n_burstduration(sc->sc_ah, bf->bf_desc, 8192);
 }
 
-static int ath_tx_setup_buffer(struct ieee80211_hw *hw, struct ath_buf *bf,
-                               struct sk_buff *skb,
-                               struct ath_tx_control *txctl)
+static struct ath_buf *ath_tx_setup_buffer(struct ieee80211_hw *hw,
+                                          struct sk_buff *skb)
 {
        struct ath_wiphy *aphy = hw->priv;
        struct ath_softc *sc = aphy->sc;
+       struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       struct ath_buf *bf;
        int hdrlen;
        __le16 fc;
        int padpos, padsize;
-       bool use_ldpc = false;
+
+       bf = ath_tx_get_buffer(sc);
+       if (!bf) {
+               ath_print(common, ATH_DBG_XMIT, "TX buffers are full\n");
+               return NULL;
+       }
 
        hdrlen = ieee80211_get_hdrlen_from_skb(skb);
        fc = hdr->frame_control;
@@ -1594,16 +1587,13 @@ static int ath_tx_setup_buffer(struct ieee80211_hw *hw, struct ath_buf *bf,
                bf->bf_frmlen -= padsize;
        }
 
-       if (!txctl->paprd && conf_is_ht(&hw->conf)) {
+       if (ieee80211_is_data_qos(fc) && conf_is_ht(&hw->conf)) {
                bf->bf_state.bf_type |= BUF_HT;
-               if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
-                       use_ldpc = true;
+               if (sc->sc_flags & SC_OP_TXAGGR)
+                       assign_aggr_tid_seqno(skb, bf);
        }
 
-       bf->bf_state.bfs_paprd = txctl->paprd;
-       if (txctl->paprd)
-               bf->bf_state.bfs_paprd_timestamp = jiffies;
-       bf->bf_flags = setup_tx_flags(skb, use_ldpc);
+       bf->bf_flags = setup_tx_flags(skb);
 
        bf->bf_keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
        if (bf->bf_keytype != ATH9K_KEY_TYPE_CLEAR) {
@@ -1613,10 +1603,6 @@ static int ath_tx_setup_buffer(struct ieee80211_hw *hw, struct ath_buf *bf,
                bf->bf_keyix = ATH9K_TXKEYIX_INVALID;
        }
 
-       if (ieee80211_is_data_qos(fc) && bf_isht(bf) &&
-           (sc->sc_flags & SC_OP_TXAGGR))
-               assign_aggr_tid_seqno(skb, bf);
-
        bf->bf_mpdu = skb;
 
        bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
@@ -1626,12 +1612,13 @@ static int ath_tx_setup_buffer(struct ieee80211_hw *hw, struct ath_buf *bf,
                bf->bf_buf_addr = 0;
                ath_print(ath9k_hw_common(sc->sc_ah), ATH_DBG_FATAL,
                          "dma_mapping_error() on TX\n");
-               return -ENOMEM;
+               ath_tx_return_buffer(sc, bf);
+               return NULL;
        }
 
        bf->bf_tx_aborted = false;
 
-       return 0;
+       return bf;
 }
 
 /* FIXME: tx power */
@@ -1679,11 +1666,6 @@ static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
                an = (struct ath_node *)tx_info->control.sta->drv_priv;
                tid = ATH_AN_2_TID(an, bf->bf_tidno);
 
-               if (!ieee80211_is_data_qos(fc)) {
-                       ath_tx_send_normal(sc, txctl->txq, &bf_head);
-                       goto tx_done;
-               }
-
                WARN_ON(tid->ac->txq != txctl->txq);
                if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
                        /*
@@ -1696,15 +1678,18 @@ static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
                         * Send this frame as regular when ADDBA
                         * exchange is neither complete nor pending.
                         */
-                       ath_tx_send_ht_normal(sc, txctl->txq,
-                                             tid, &bf_head);
+                       ath_tx_send_normal(sc, txctl->txq, tid, &bf_head);
                }
        } else {
                bf->bf_state.bfs_ftype = txctl->frame_type;
-               ath_tx_send_normal(sc, txctl->txq, &bf_head);
+               bf->bf_state.bfs_paprd = txctl->paprd;
+
+               if (txctl->paprd)
+                       bf->bf_state.bfs_paprd_timestamp = jiffies;
+
+               ath_tx_send_normal(sc, txctl->txq, NULL, &bf_head);
        }
 
-tx_done:
        spin_unlock_bh(&txctl->txq->axq_lock);
 }
 
@@ -1714,39 +1699,15 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
 {
        struct ath_wiphy *aphy = hw->priv;
        struct ath_softc *sc = aphy->sc;
-       struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_txq *txq = txctl->txq;
        struct ath_buf *bf;
-       int q, r;
+       int q;
 
-       bf = ath_tx_get_buffer(sc);
-       if (!bf) {
-               ath_print(common, ATH_DBG_XMIT, "TX buffers are full\n");
-               return -1;
-       }
+       bf = ath_tx_setup_buffer(hw, skb);
+       if (unlikely(!bf))
+               return -ENOMEM;
 
        q = skb_get_queue_mapping(skb);
-       r = ath_tx_setup_buffer(hw, bf, skb, txctl);
-       if (unlikely(r)) {
-               ath_print(common, ATH_DBG_FATAL, "TX mem alloc failure\n");
-
-               /* upon ath_tx_processq() this TX queue will be resumed, we
-                * guarantee this will happen by knowing beforehand that
-                * we will at least have to run TX completionon one buffer
-                * on the queue */
-               spin_lock_bh(&txq->axq_lock);
-               if (txq == sc->tx.txq_map[q] && !txq->stopped &&
-                   txq->axq_depth > 1) {
-                       ath_mac80211_stop_queue(sc, q);
-                       txq->stopped = 1;
-               }
-               spin_unlock_bh(&txq->axq_lock);
-
-               ath_tx_return_buffer(sc, bf);
-
-               return r;
-       }
-
        spin_lock_bh(&txq->axq_lock);
        if (txq == sc->tx.txq_map[q] &&
            ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) {