This patch is adapted from the submission by Michael Buesch <[email protected]>
for a bounce-buffer copying problem with b43.
Signed-off-by: Larry Finger <[email protected]>
---
John,
Full testing of this patch is a problem as the bounce buffer can come into
play only when the test machine has more than 1 GB RAM. When I coded the
original bounce-buffer code for bcm43xx, I had such a machine, but it
died. I tested the patch on a machine with 256 MB and it works. As it
is a line-by-line copy of Michael's patch, it should be OK. In any case, this
is 2.6.33 material.
Larry
---
Index: wireless-testing/drivers/net/wireless/b43legacy/dma.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43legacy/dma.c
+++ wireless-testing/drivers/net/wireless/b43legacy/dma.c
@@ -1240,8 +1240,9 @@ struct b43legacy_dmaring *parse_cookie(s
}
static int dma_tx_fragment(struct b43legacy_dmaring *ring,
- struct sk_buff *skb)
+ struct sk_buff **in_skb)
{
+ struct sk_buff *skb = *in_skb;
const struct b43legacy_dma_ops *ops = ring->ops;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
u8 *header;
@@ -1305,8 +1306,14 @@ static int dma_tx_fragment(struct b43leg
}
memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
+ memcpy(bounce_skb->cb, skb->cb, sizeof(skb->cb));
+ bounce_skb->dev = skb->dev;
+ skb_set_queue_mapping(bounce_skb, skb_get_queue_mapping(skb));
+ info = IEEE80211_SKB_CB(bounce_skb);
+
dev_kfree_skb_any(skb);
skb = bounce_skb;
+ *in_skb = bounce_skb;
meta->skb = skb;
meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
@@ -1360,8 +1367,10 @@ int b43legacy_dma_tx(struct b43legacy_wl
struct sk_buff *skb)
{
struct b43legacy_dmaring *ring;
+ struct ieee80211_hdr *hdr;
int err = 0;
unsigned long flags;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
ring = priority_to_txring(dev, skb_get_queue_mapping(skb));
spin_lock_irqsave(&ring->lock, flags);
@@ -1386,7 +1395,11 @@ int b43legacy_dma_tx(struct b43legacy_wl
goto out_unlock;
}
- err = dma_tx_fragment(ring, skb);
+ /* dma_tx_fragment might reallocate the skb, so invalidate pointers pointing
+ * into the skb data or cb now. */
+ hdr = NULL;
+ info = NULL;
+ err = dma_tx_fragment(ring, &skb);
if (unlikely(err == -ENOKEY)) {
/* Drop this packet, as we don't have the encryption key
* anymore and must not transmit it unencrypted. */