From bea893364784582d03494348a91b2c63e0d540d3 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Wed, 10 Apr 2013 20:35:29 +0000 Subject: [PATCH] xen-netback: switch to use skb_partial_csum_set() Switch to use skb_partial_csum_set() to simplify the codes. Cc: Ian Campbell Signed-off-by: Jason Wang Signed-off-by: David S. Miller --- drivers/net/xen-netback/netback.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 01a33cc58cf1..9f7184404263 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1156,7 +1156,6 @@ static int netbk_set_skb_gso(struct xenvif *vif, static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) { struct iphdr *iph; - unsigned char *th; int err = -EPROTO; int recalculate_partial_csum = 0; @@ -1180,28 +1179,26 @@ static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) goto out; iph = (void *)skb->data; - th = skb->data + 4 * iph->ihl; - if (th >= skb_tail_pointer(skb)) - goto out; - - skb_set_transport_header(skb, 4 * iph->ihl); - skb->csum_start = th - skb->head; switch (iph->protocol) { case IPPROTO_TCP: - skb->csum_offset = offsetof(struct tcphdr, check); + if (!skb_partial_csum_set(skb, 4 * iph->ihl, + offsetof(struct tcphdr, check))) + goto out; if (recalculate_partial_csum) { - struct tcphdr *tcph = (struct tcphdr *)th; + struct tcphdr *tcph = tcp_hdr(skb); tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len - iph->ihl*4, IPPROTO_TCP, 0); } break; case IPPROTO_UDP: - skb->csum_offset = offsetof(struct udphdr, check); + if (!skb_partial_csum_set(skb, 4 * iph->ihl, + offsetof(struct udphdr, check))) + goto out; if (recalculate_partial_csum) { - struct udphdr *udph = (struct udphdr *)th; + struct udphdr *udph = udp_hdr(skb); udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len - iph->ihl*4, IPPROTO_UDP, 0); @@ -1215,9 +1212,6 @@ static int checksum_setup(struct xenvif *vif, struct sk_buff *skb) goto out; } - if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb)) - goto out; - err = 0; out: