diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2006-06-23 13:06:41 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-06-23 13:06:41 +0400 |
| commit | 5b057c6b1a25d57edf2b4d1e956e50936480a9ff (patch) | |
| tree | e641febd6f562e0ed1198c160ff353ab513f0612 /drivers/net/wireless | |
| parent | 5fa21d821f6972e70942f2c555ec29dde962bdb2 (diff) | |
| download | linux-5b057c6b1a25d57edf2b4d1e956e50936480a9ff.tar.xz | |
[NET]: Avoid allocating skb in skb_pad
First of all it is unnecessary to allocate a new skb in skb_pad since
the existing one is not shared. More importantly, our hard_start_xmit
interface does not allow a new skb to be allocated since that breaks
requeueing.
This patch uses pskb_expand_head to expand the existing skb and linearize
it if needed. Actually, someone should sift through every instance of
skb_pad on a non-linear skb as they do not fit the reasons why this was
originally created.
Incidentally, this fixes a minor bug when the skb is cloned (tcpdump,
TCP, etc.). As it is skb_pad will simply write over a cloned skb. Because
of the position of the write it is unlikely to cause problems but still
it's best if we don't do it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/wireless')
| -rw-r--r-- | drivers/net/wireless/ray_cs.c | 3 | ||||
| -rw-r--r-- | drivers/net/wireless/wavelan_cs.c | 7 |
2 files changed, 3 insertions, 7 deletions
diff --git a/drivers/net/wireless/ray_cs.c b/drivers/net/wireless/ray_cs.c index 879eb427607c..a915fe6c6aa5 100644 --- a/drivers/net/wireless/ray_cs.c +++ b/drivers/net/wireless/ray_cs.c @@ -924,8 +924,7 @@ static int ray_dev_start_xmit(struct sk_buff *skb, struct net_device *dev) if (length < ETH_ZLEN) { - skb = skb_padto(skb, ETH_ZLEN); - if (skb == NULL) + if (skb_padto(skb, ETH_ZLEN)) return 0; length = ETH_ZLEN; } diff --git a/drivers/net/wireless/wavelan_cs.c b/drivers/net/wireless/wavelan_cs.c index f7724eb2fa7e..561250f73fd3 100644 --- a/drivers/net/wireless/wavelan_cs.c +++ b/drivers/net/wireless/wavelan_cs.c @@ -3194,11 +3194,8 @@ wavelan_packet_xmit(struct sk_buff * skb, * and we don't have the Ethernet specific requirement of beeing * able to detect collisions, therefore in theory we don't really * need to pad. Jean II */ - if (skb->len < ETH_ZLEN) { - skb = skb_padto(skb, ETH_ZLEN); - if (skb == NULL) - return 0; - } + if (skb_padto(skb, ETH_ZLEN)) + return 0; wv_packet_write(dev, skb->data, skb->len); |