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>

2 files changed, 32 insertions, 39 deletions

diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index 32ee351a765..7d97934265d 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
diff --git a/drivers/net/wireless/ath5k/base.h b/drivers/net/wireless/ath5k/base.h
index ecb17495488..bb4b26d523a 100644
--- a/drivers/net/wireless/ath5k/base.h
+++ b/drivers/net/wireless/ath5k/base.h
@@ -60,7 +60,6 @@ struct ath5k_buf {
 	dma_addr_t		daddr;	/* physical addr of desc */
 	struct sk_buff		*skb;	/* skbuff for buf */
 	dma_addr_t		skbaddr;/* physical addr of skb data */
-	struct ieee80211_tx_control ctl;
 };
 
 /*