[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Fri, 12 Dec 2008 22:55:40 +0000
From: Ben Hutchings <bhutchings@...arflare.com>
To: Herbert Xu <herbert@...dor.apana.org.au>
Cc: "David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH 4/8] ipv4: Add GRO infrastructure
On Fri, 2008-12-12 at 16:31 +1100, Herbert Xu wrote:
[...]
> diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
> index 1aa2dc9..260f081 100644
> --- a/net/ipv4/af_inet.c
> +++ b/net/ipv4/af_inet.c
> @@ -94,6 +94,7 @@
> #include <linux/igmp.h>
> #include <linux/inetdevice.h>
> #include <linux/netdevice.h>
> +#include <net/checksum.h>
> #include <net/ip.h>
> #include <net/protocol.h>
> #include <net/arp.h>
> @@ -1245,6 +1246,99 @@ out:
> return segs;
> }
>
> +static struct sk_buff **inet_gro_receive(struct sk_buff **head,
> + struct sk_buff *skb)
> +{
> + struct net_protocol *ops;
> + struct sk_buff **pp = NULL;
> + struct sk_buff *p;
> + struct iphdr *iph;
> + int flush = 1;
> + int proto;
> + int id;
> +
> + if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
> + goto out;
> +
> + iph = ip_hdr(skb);
> + proto = iph->protocol & (MAX_INET_PROTOS - 1);
> +
> + rcu_read_lock();
> + ops = rcu_dereference(inet_protos[proto]);
> + if (!ops || !ops->gro_receive)
> + goto out_unlock;
> +
> + if (iph->version != 4 || iph->ihl != 5)
> + goto out_unlock;
> +
> + if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
> + goto out_unlock;
Don't we also need to check that skb->len >= iph->ihl * 4?
> + flush = ntohs(iph->tot_len) != skb->len ||
> + iph->frag_off != htons(IP_DF);
> + id = ntohs(iph->id);
> +
> + for (p = *head; p; p = p->next) {
> + struct iphdr *iph2;
> +
> + if (!NAPI_GRO_CB(p)->same_flow)
> + continue;
> +
> + iph2 = ip_hdr(p);
> +
> + if (iph->protocol != iph2->protocol ||
> + memcmp(&iph->saddr, &iph2->saddr, 8)) {
> + NAPI_GRO_CB(p)->same_flow = 0;
> + continue;
> + }
> +
> + /* All fields must match except length and checksum. */
> + NAPI_GRO_CB(p)->flush |=
> + memcmp(&iph->frag_off, &iph2->frag_off, 4) ||
This covers frag_off, ttl and protocol. But frag_off and protocol have
already been covered, and tos seems to have been missed.
> + (u16)(ntohs(iph2->id) + NAPI_GRO_CB(p)->count) != id;
> + NAPI_GRO_CB(p)->flush |= flush;
> + }
> +
> + NAPI_GRO_CB(skb)->flush |= flush;
> + __skb_pull(skb, sizeof(*iph));
> + skb_reset_transport_header(skb);
> +
> + pp = ops->gro_receive(head, skb);
> +
> +out_unlock:
> + rcu_read_unlock();
> +
> +out:
> + NAPI_GRO_CB(skb)->flush |= flush;
> +
> + return pp;
> +}
[...]
Ben.
--
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists