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, 43 insertions, 31 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index c5cedb29b87d..b5379b027b18 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -31,14 +31,15 @@
 
 static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
                                 struct data_queue *queue,
-                                struct sk_buff *frag_skb,
-                                struct ieee80211_tx_control *control)
+                                struct sk_buff *frag_skb)
 {
+        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(frag_skb);
         struct skb_frame_desc *skbdesc;
+        struct ieee80211_tx_info *rts_info;
         struct sk_buff *skb;
         int size;
 
-        if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
+        if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
                 size = sizeof(struct ieee80211_cts);
         else
                 size = sizeof(struct ieee80211_rts);
@@ -52,13 +53,33 @@ static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
         skb_put(skb, size);
 
-        if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
-                ieee80211_ctstoself_get(rt2x00dev->hw, control->vif,
-                                        frag_skb->data, frag_skb->len, control,
+        /*
+         * Copy TX information over from original frame to
+         * RTS/CTS frame. Note that we set the no encryption flag
+         * since we don't want this frame to be encrypted.
+         * RTS frames should be acked, while CTS-to-self frames
+         * should not. The ready for TX flag is cleared to prevent
+         * it being automatically send when the descriptor is
+         * written to the hardware.
+         */
+        memcpy(skb->cb, frag_skb->cb, sizeof(skb->cb));
+        rts_info = IEEE80211_SKB_CB(skb);
+        rts_info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT;
+        rts_info->flags &= ~IEEE80211_TX_CTL_USE_CTS_PROTECT;
+        rts_info->flags &= ~IEEE80211_TX_CTL_REQ_TX_STATUS;
+
+        if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
+                rts_info->flags |= IEEE80211_TX_CTL_NO_ACK;
+        else
+                rts_info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
+
+        if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
+                ieee80211_ctstoself_get(rt2x00dev->hw, tx_info->control.vif,
+                                        frag_skb->data, size, tx_info,
                                         (struct ieee80211_cts *)(skb->data));
         else
-                ieee80211_rts_get(rt2x00dev->hw, control->vif,
-                                  frag_skb->data, frag_skb->len, control,
+                ieee80211_rts_get(rt2x00dev->hw, tx_info->control.vif,
+                                  frag_skb->data, size, tx_info,
                                   (struct ieee80211_rts *)(skb->data));
 
         /*
@@ -68,7 +89,7 @@ static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
         memset(skbdesc, 0, sizeof(*skbdesc));
         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
 
-        if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
+        if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
                 return NETDEV_TX_BUSY;
         }
@@ -76,14 +97,13 @@ static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
         return NETDEV_TX_OK;
 }
 
-int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
-                 struct ieee80211_tx_control *control)
+int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 {
         struct rt2x00_dev *rt2x00dev = hw->priv;
+        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
-        enum data_queue_qid qid = mac80211_queue_to_qid(control->queue);
+        enum data_queue_qid qid = mac80211_queue_to_qid(tx_info->queue);
         struct data_queue *queue;
-        struct skb_frame_desc *skbdesc;
         u16 frame_control;
 
         /*
@@ -100,7 +120,7 @@ int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
         /*
          * Determine which queue to put packet on.
          */
-        if (control->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM &&
+        if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
                 queue = rt2x00queue_get_queue(rt2x00dev, QID_ATIM);
         else
@@ -125,33 +145,27 @@ int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
          */
         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
-            (control->flags & (IEEE80211_TXCTL_USE_RTS_CTS |
-                               IEEE80211_TXCTL_USE_CTS_PROTECT)) &&
+            (tx_info->flags & (IEEE80211_TX_CTL_USE_RTS_CTS |
+                               IEEE80211_TX_CTL_USE_CTS_PROTECT)) &&
             !rt2x00dev->ops->hw->set_rts_threshold) {
                 if (rt2x00queue_available(queue) <= 1) {
-                        ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+                        ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
                         return NETDEV_TX_BUSY;
                 }
 
-                if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb, control)) {
-                        ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+                if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb)) {
+                        ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
                         return NETDEV_TX_BUSY;
                 }
         }
 
-        /*
-         * Initialize skb descriptor
-         */
-        skbdesc = get_skb_frame_desc(skb);
-        memset(skbdesc, 0, sizeof(*skbdesc));
-
-        if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
-                ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+        if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
+                ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
                 return NETDEV_TX_BUSY;
         }
 
         if (rt2x00queue_full(queue))
-                ieee80211_stop_queue(rt2x00dev->hw, control->queue);
+                ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
 
         if (rt2x00dev->ops->lib->kick_tx_queue)
                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, qid);
@@ -380,9 +394,7 @@ int rt2x00mac_config_interface(struct ieee80211_hw *hw,
         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
                 return 0;
 
-        status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw,
-                                                   conf->beacon,
-                                                   conf->beacon_control);
+        status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw, conf->beacon);
         if (status)
                 dev_kfree_skb(conf->beacon);