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>
diff --git a/drivers/net/wireless/b43legacy/pio.c b/drivers/net/wireless/b43legacy/pio.c
index 8d3d27d..a86c764 100644
--- a/drivers/net/wireless/b43legacy/pio.c
+++ b/drivers/net/wireless/b43legacy/pio.c
@@ -196,7 +196,7 @@
 	B43legacy_WARN_ON(skb_shinfo(skb)->nr_frags != 0);
 	err = b43legacy_generate_txhdr(queue->dev,
 				 txhdr, skb->data, skb->len,
-				 &packet->txstat.control,
+				 IEEE80211_SKB_CB(skb),
 				 generate_cookie(queue, packet));
 	if (err)
 		return err;
@@ -463,8 +463,7 @@
 }
 
 int b43legacy_pio_tx(struct b43legacy_wldev *dev,
-		     struct sk_buff *skb,
-		     struct ieee80211_tx_control *ctl)
+		     struct sk_buff *skb)
 {
 	struct b43legacy_pioqueue *queue = dev->pio.queue1;
 	struct b43legacy_pio_txpacket *packet;
@@ -476,9 +475,6 @@
 			    list);
 	packet->skb = skb;
 
-	memset(&packet->txstat, 0, sizeof(packet->txstat));
-	memcpy(&packet->txstat.control, ctl, sizeof(*ctl));
-
 	list_move_tail(&packet->list, &queue->txqueue);
 	queue->nr_txfree--;
 	queue->nr_tx_packets++;
@@ -494,6 +490,7 @@
 {
 	struct b43legacy_pioqueue *queue;
 	struct b43legacy_pio_txpacket *packet;
+	struct ieee80211_tx_info *info;
 
 	queue = parse_cookie(dev, status->cookie, &packet);
 	B43legacy_WARN_ON(!queue);
@@ -505,11 +502,13 @@
 	queue->tx_devq_used -= (packet->skb->len +
 				sizeof(struct b43legacy_txhdr_fw3));
 
+	info = IEEE80211_SKB_CB(packet->skb);
+	memset(&info->status, 0, sizeof(info->status));
+
 	if (status->acked)
-		packet->txstat.flags |= IEEE80211_TX_STATUS_ACK;
-	packet->txstat.retry_count = status->frame_count - 1;
-	ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb,
-				    &(packet->txstat));
+		info->flags |= IEEE80211_TX_STAT_ACK;
+	info->status.retry_count = status->frame_count - 1;
+	ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb);
 	packet->skb = NULL;
 
 	free_txpacket(packet, 1);