mac80211: move TX info into skb->cb

This patch converts mac80211 and all drivers to have transmit
information and status in skb->cb rather than allocating extra
memory for it and copying all the data around. To make it fit,
a union is used where only data that is necessary for all steps
is kept outside of the union.

A number of fixes were done by Ivo, as well as the rt2x00 part
of this patch.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 32 insertions, 38 deletions

diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index 32ee351a7650..7d97934265db 100644
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -167,8 +167,7 @@ static struct pci_driver ath5k_pci_driver = {
 /*
  * Prototypes - MAC 802.11 stack related functions
  */
-static int ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
-                struct ieee80211_tx_control *ctl);
+static int ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb);
 static int ath5k_reset(struct ieee80211_hw *hw);
 static int ath5k_start(struct ieee80211_hw *hw);
 static void ath5k_stop(struct ieee80211_hw *hw);
@@ -196,8 +195,7 @@ static int ath5k_get_tx_stats(struct ieee80211_hw *hw,
 static u64 ath5k_get_tsf(struct ieee80211_hw *hw);
 static void ath5k_reset_tsf(struct ieee80211_hw *hw);
 static int ath5k_beacon_update(struct ieee80211_hw *hw,
-                struct sk_buff *skb,
-                struct ieee80211_tx_control *ctl);
+                struct sk_buff *skb);
 
 static struct ieee80211_ops ath5k_hw_ops = {
         .tx             = ath5k_tx,
@@ -251,9 +249,7 @@ static void	ath5k_desc_free(struct ath5k_softc *sc,
 static int      ath5k_rxbuf_setup(struct ath5k_softc *sc,
                                 struct ath5k_buf *bf);
 static int      ath5k_txbuf_setup(struct ath5k_softc *sc,
-                                struct ath5k_buf *bf,
-                                struct ieee80211_tx_control *ctl);
-
+                                struct ath5k_buf *bf);
 static inline void ath5k_txbuf_free(struct ath5k_softc *sc,
                                 struct ath5k_buf *bf)
 {
@@ -289,8 +285,7 @@ static void 	ath5k_tx_processq(struct ath5k_softc *sc,
 static void     ath5k_tasklet_tx(unsigned long data);
 /* Beacon handling */
 static int      ath5k_beacon_setup(struct ath5k_softc *sc,
-                                struct ath5k_buf *bf,
-                                struct ieee80211_tx_control *ctl);
+                                        struct ath5k_buf *bf);
 static void     ath5k_beacon_send(struct ath5k_softc *sc);
 static void     ath5k_beacon_config(struct ath5k_softc *sc);
 static void     ath5k_beacon_update_timers(struct ath5k_softc *sc, u64 bc_tsf);
@@ -1295,37 +1290,36 @@ ath5k_rxbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf)
 }
 
 static int
-ath5k_txbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf,
-                struct ieee80211_tx_control *ctl)
+ath5k_txbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf)
 {
         struct ath5k_hw *ah = sc->ah;
         struct ath5k_txq *txq = sc->txq;
         struct ath5k_desc *ds = bf->desc;
         struct sk_buff *skb = bf->skb;
+        struct ieee80211_tx_info *info = (void*) skb->cb;
         unsigned int pktlen, flags, keyidx = AR5K_TXKEYIX_INVALID;
         int ret;
 
         flags = AR5K_TXDESC_INTREQ | AR5K_TXDESC_CLRDMASK;
-        bf->ctl = *ctl;
+
         /* XXX endianness */
         bf->skbaddr = pci_map_single(sc->pdev, skb->data, skb->len,
                         PCI_DMA_TODEVICE);
 
-        if (ctl->flags & IEEE80211_TXCTL_NO_ACK)
+        if (info->flags & IEEE80211_TX_CTL_NO_ACK)
                 flags |= AR5K_TXDESC_NOACK;
 
         pktlen = skb->len;
 
-        if (!(ctl->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT)) {
-                keyidx = ctl->hw_key->hw_key_idx;
-                pktlen += ctl->icv_len;
+        if (!(info->flags & IEEE80211_TX_CTL_DO_NOT_ENCRYPT)) {
+                keyidx = info->control.hw_key->hw_key_idx;
+                pktlen += info->control.icv_len;
         }
-
         ret = ah->ah_setup_tx_desc(ah, ds, pktlen,
                 ieee80211_get_hdrlen_from_skb(skb), AR5K_PKT_TYPE_NORMAL,
                 (sc->power_level * 2),
-                ieee80211_get_tx_rate(sc->hw, ctl)->hw_value,
-                ctl->retry_limit, keyidx, 0, flags, 0, 0);
+                ieee80211_get_tx_rate(sc->hw, info)->hw_value,
+                info->control.retry_limit, keyidx, 0, flags, 0, 0);
         if (ret)
                 goto err_unmap;
 
@@ -1927,11 +1921,11 @@ next:
 static void
 ath5k_tx_processq(struct ath5k_softc *sc, struct ath5k_txq *txq)
 {
-        struct ieee80211_tx_status txs = {};
         struct ath5k_tx_status ts = {};
         struct ath5k_buf *bf, *bf0;
         struct ath5k_desc *ds;
         struct sk_buff *skb;
+        struct ieee80211_tx_info *info;
         int ret;
 
         spin_lock(&txq->lock);
@@ -1951,24 +1945,25 @@ ath5k_tx_processq(struct ath5k_softc *sc, struct ath5k_txq *txq)
                 }
 
                 skb = bf->skb;
+                info = (void*) skb->cb;
                 bf->skb = NULL;
+
                 pci_unmap_single(sc->pdev, bf->skbaddr, skb->len,
                                 PCI_DMA_TODEVICE);
 
-                txs.control = bf->ctl;
-                txs.retry_count = ts.ts_shortretry + ts.ts_longretry / 6;
+                info->status.retry_count = ts.ts_shortretry + ts.ts_longretry / 6;
                 if (unlikely(ts.ts_status)) {
                         sc->ll_stats.dot11ACKFailureCount++;
                         if (ts.ts_status & AR5K_TXERR_XRETRY)
-                                txs.excessive_retries = 1;
+                                info->status.excessive_retries = 1;
                         else if (ts.ts_status & AR5K_TXERR_FILT)
-                                txs.flags |= IEEE80211_TX_STATUS_TX_FILTERED;
+                                info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
                 } else {
-                        txs.flags |= IEEE80211_TX_STATUS_ACK;
-                        txs.ack_signal = ts.ts_rssi;
+                        info->flags |= IEEE80211_TX_STAT_ACK;
+                        info->status.ack_signal = ts.ts_rssi;
                 }
 
-                ieee80211_tx_status(sc->hw, skb, &txs);
+                ieee80211_tx_status(sc->hw, skb);
                 sc->tx_stats[txq->qnum].count++;
 
                 spin_lock(&sc->txbuflock);
@@ -2005,10 +2000,10 @@ ath5k_tasklet_tx(unsigned long data)
  * Setup the beacon frame for transmit.
  */
 static int
-ath5k_beacon_setup(struct ath5k_softc *sc, struct ath5k_buf *bf,
-                struct ieee80211_tx_control *ctl)
+ath5k_beacon_setup(struct ath5k_softc *sc, struct ath5k_buf *bf)
 {
         struct sk_buff *skb = bf->skb;
+        struct  ieee80211_tx_info *info = (void*) skb->cb;
         struct ath5k_hw *ah = sc->ah;
         struct ath5k_desc *ds;
         int ret, antenna = 0;
@@ -2047,7 +2042,7 @@ ath5k_beacon_setup(struct ath5k_softc *sc, struct ath5k_buf *bf,
         ret = ah->ah_setup_tx_desc(ah, ds, skb->len,
                         ieee80211_get_hdrlen_from_skb(skb),
                         AR5K_PKT_TYPE_BEACON, (sc->power_level * 2),
-                        ieee80211_get_tx_rate(sc->hw, ctl)->hw_value,
+                        ieee80211_get_tx_rate(sc->hw, info)->hw_value,
                         1, AR5K_TXKEYIX_INVALID,
                         antenna, flags, 0, 0);
         if (ret)
@@ -2626,11 +2621,11 @@ ath5k_led_event(struct ath5k_softc *sc, int event)
 \********************/
 
 static int
-ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
-                        struct ieee80211_tx_control *ctl)
+ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
         struct ath5k_softc *sc = hw->priv;
         struct ath5k_buf *bf;
+        struct ieee80211_tx_info *info = (void*) skb->cb;
         unsigned long flags;
         int hdrlen;
         int pad;
@@ -2656,13 +2651,13 @@ ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
                 memmove(skb->data, skb->data+pad, hdrlen);
         }
 
-        sc->led_txrate = ieee80211_get_tx_rate(hw, ctl)->hw_value;
+        sc->led_txrate = ieee80211_get_tx_rate(hw, info)->hw_value;
 
         spin_lock_irqsave(&sc->txbuflock, flags);
         if (list_empty(&sc->txbuf)) {
                 ATH5K_ERR(sc, "no further txbuf available, dropping packet\n");
                 spin_unlock_irqrestore(&sc->txbuflock, flags);
-                ieee80211_stop_queue(hw, ctl->queue);
+                ieee80211_stop_queue(hw, info->queue);
                 return -1;
         }
         bf = list_first_entry(&sc->txbuf, struct ath5k_buf, list);
@@ -2674,7 +2669,7 @@ ath5k_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
 
         bf->skb = skb;
 
-        if (ath5k_txbuf_setup(sc, bf, ctl)) {
+        if (ath5k_txbuf_setup(sc, bf)) {
                 bf->skb = NULL;
                 spin_lock_irqsave(&sc->txbuflock, flags);
                 list_add_tail(&bf->list, &sc->txbuf);
@@ -3052,8 +3047,7 @@ ath5k_reset_tsf(struct ieee80211_hw *hw)
 }
 
 static int
-ath5k_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
-                        struct ieee80211_tx_control *ctl)
+ath5k_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
         struct ath5k_softc *sc = hw->priv;
         int ret;
@@ -3069,7 +3063,7 @@ ath5k_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
 
         ath5k_txbuf_free(sc, sc->bbuf);
         sc->bbuf->skb = skb;
-        ret = ath5k_beacon_setup(sc, sc->bbuf, ctl);
+        ret = ath5k_beacon_setup(sc, sc->bbuf);
         if (ret)
                 sc->bbuf->skb = NULL;
         else