From 4fd671ded14f92cb8db0bf72747f4df508ba5e3d Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Tue, 25 Nov 2014 11:21:20 -0800 Subject: [PATCH] gue: Call remcsum_adjust Change remote checksum offload to call remcsum_adjust. This also eliminates the optimization to skip an IP header as part of the adjustment (really does not seem to be much of a win). Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- net/ipv4/fou.c | 84 ++++++++++---------------------------------------- 1 file changed, 17 insertions(+), 67 deletions(-) diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index 3dfe9828e7ef..b986298a7ba3 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -64,15 +64,13 @@ static int fou_udp_recv(struct sock *sk, struct sk_buff *skb) } static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, - void *data, int hdrlen, u8 ipproto) + void *data, size_t hdrlen, u8 ipproto) { __be16 *pd = data; - u16 start = ntohs(pd[0]); - u16 offset = ntohs(pd[1]); - u16 poffset = 0; - u16 plen; - __wsum csum, delta; - __sum16 *psum; + size_t start = ntohs(pd[0]); + size_t offset = ntohs(pd[1]); + size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); + __wsum delta; if (skb->remcsum_offload) { /* Already processed in GRO path */ @@ -80,35 +78,15 @@ static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, return guehdr; } - if (start > skb->len - hdrlen || - offset > skb->len - hdrlen - sizeof(u16)) - return NULL; - - if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) - __skb_checksum_complete(skb); - - plen = hdrlen + offset + sizeof(u16); if (!pskb_may_pull(skb, plen)) return NULL; guehdr = (struct guehdr *)&udp_hdr(skb)[1]; - if (ipproto == IPPROTO_IP && sizeof(struct iphdr) < plen) { - struct iphdr *ip = (struct iphdr *)(skb->data + hdrlen); - - /* If next header happens to be IP we can skip that for the - * checksum calculation since the IP header checksum is zero - * if correct. - */ - poffset = ip->ihl * 4; - } - - csum = csum_sub(skb->csum, skb_checksum(skb, poffset + hdrlen, - start - poffset - hdrlen, 0)); + if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) + __skb_checksum_complete(skb); - /* Set derived checksum in packet */ - psum = (__sum16 *)(skb->data + hdrlen + offset); - delta = csum_sub(csum_fold(csum), *psum); - *psum = csum_fold(csum); + delta = remcsum_adjust((void *)guehdr + hdrlen, + skb->csum, start, offset); /* Adjust skb->csum since we changed the packet */ skb->csum = csum_add(skb->csum, delta); @@ -158,9 +136,6 @@ static int gue_udp_recv(struct sock *sk, struct sk_buff *skb) ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(skb)->tot_len) - len); - /* Pull UDP header now, skb->data points to guehdr */ - __skb_pull(skb, sizeof(struct udphdr)); - /* Pull csum through the guehdr now . This can be used if * there is a remote checksum offload. */ @@ -188,7 +163,7 @@ static int gue_udp_recv(struct sock *sk, struct sk_buff *skb) if (unlikely(guehdr->control)) return gue_control_message(skb, guehdr); - __skb_pull(skb, hdrlen); + __skb_pull(skb, sizeof(struct udphdr) + hdrlen); skb_reset_transport_header(skb); return -guehdr->proto_ctype; @@ -248,24 +223,17 @@ static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off, size_t hdrlen, u8 ipproto) { __be16 *pd = data; - u16 start = ntohs(pd[0]); - u16 offset = ntohs(pd[1]); - u16 poffset = 0; - u16 plen; - void *ptr; - __wsum csum, delta; - __sum16 *psum; + size_t start = ntohs(pd[0]); + size_t offset = ntohs(pd[1]); + size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start); + __wsum delta; if (skb->remcsum_offload) return guehdr; - if (start > skb_gro_len(skb) - hdrlen || - offset > skb_gro_len(skb) - hdrlen - sizeof(u16) || - !NAPI_GRO_CB(skb)->csum_valid || skb->remcsum_offload) + if (!NAPI_GRO_CB(skb)->csum_valid) return NULL; - plen = hdrlen + offset + sizeof(u16); - /* Pull checksum that will be written */ if (skb_gro_header_hard(skb, off + plen)) { guehdr = skb_gro_header_slow(skb, off + plen, off); @@ -273,26 +241,8 @@ static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off, return NULL; } - ptr = (void *)guehdr + hdrlen; - - if (ipproto == IPPROTO_IP && - (hdrlen + sizeof(struct iphdr) < plen)) { - struct iphdr *ip = (struct iphdr *)(ptr + hdrlen); - - /* If next header happens to be IP we can skip - * that for the checksum calculation since the - * IP header checksum is zero if correct. - */ - poffset = ip->ihl * 4; - } - - csum = csum_sub(NAPI_GRO_CB(skb)->csum, - csum_partial(ptr + poffset, start - poffset, 0)); - - /* Set derived checksum in packet */ - psum = (__sum16 *)(ptr + offset); - delta = csum_sub(csum_fold(csum), *psum); - *psum = csum_fold(csum); + delta = remcsum_adjust((void *)guehdr + hdrlen, + NAPI_GRO_CB(skb)->csum, start, offset); /* Adjust skb->csum since we changed the packet */ skb->csum = csum_add(skb->csum, delta); -- 2.30.2