redonkable/alistair23-linux
redonkable/alistair23-linux
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rt2x00: Don't use pskb_expand_head()

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rt2x00pci allocates DMA for descriptor and data,
rt61pci doesn't use this for the beacon, but it can
use the descriptor part as temporary buffer instead
of using pskb_expand_head().
Using this temporary buffer is obviously much better
then reallocating the skb buffer...

At the same time we can set the data length for the
beacon queue at 0, to make sure no DMA is allocated for
data (but just for the descriptor).

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Ivo van Doorn 2008-05-05 17:23:31 +02:00 committed by John W. Linville
parent 6243065d30
commit 7872089745
1 changed files with 11 additions and 20 deletions
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31
drivers/net/wireless/rt2x00/rt61pci.c
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@ -2366,6 +2366,7 @@ static int rt61pci_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
{
struct rt2x00_dev *rt2x00dev = hw->priv;
struct rt2x00_intf *intf = vif_to_intf(control->vif);
struct queue_entry_priv_pci_tx *priv_tx;
struct skb_frame_desc *skbdesc;
unsigned int beacon_base;
u32 reg;
@ -2373,21 +2374,8 @@ static int rt61pci_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
if (unlikely(!intf->beacon))
return -ENOBUFS;
/*
* We need to append the descriptor in front of the
* beacon frame.
*/
if (skb_headroom(skb) < intf->beacon->queue->desc_size) {
if (pskb_expand_head(skb, intf->beacon->queue->desc_size,
0, GFP_ATOMIC))
return -ENOMEM;
}
/*
* Add the descriptor in front of the skb.
*/
skb_push(skb, intf->beacon->queue->desc_size);
memset(skb->data, 0, intf->beacon->queue->desc_size);
priv_tx = intf->beacon->priv_data;
memset(priv_tx->desc, 0, intf->beacon->queue->desc_size);
/*
* Fill in skb descriptor
@ -2395,9 +2383,9 @@ static int rt61pci_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data + intf->beacon->queue->desc_size;
skbdesc->data_len = skb->len - intf->beacon->queue->desc_size;
skbdesc->desc = skb->data;
skbdesc->data = skb->data;
skbdesc->data_len = skb->len;
skbdesc->desc = priv_tx->desc;
skbdesc->desc_len = intf->beacon->queue->desc_size;
skbdesc->entry = intf->beacon;
@ -2425,7 +2413,10 @@ static int rt61pci_beacon_update(struct ieee80211_hw *hw, struct sk_buff *skb,
*/
beacon_base = HW_BEACON_OFFSET(intf->beacon->entry_idx);
rt2x00pci_register_multiwrite(rt2x00dev, beacon_base,
skb->data, skb->len);
skbdesc->desc, skbdesc->desc_len);
rt2x00pci_register_multiwrite(rt2x00dev,
beacon_base + skbdesc->desc_len,
skbdesc->data, skbdesc->data_len);
rt61pci_kick_tx_queue(rt2x00dev, control->queue);
return 0;
@ -2490,7 +2481,7 @@ static const struct data_queue_desc rt61pci_queue_tx = {
static const struct data_queue_desc rt61pci_queue_bcn = {
.entry_num = 4 * BEACON_ENTRIES,
.data_size = MGMT_FRAME_SIZE,
.data_size = 0, /* No DMA required for beacons */
.desc_size = TXINFO_SIZE,
.priv_size = sizeof(struct queue_entry_priv_pci_tx),
};