From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: [RFC][PATCH 4/5] I/OAT DMA support and TCP acceleration
Date: Tue, 20 Dec 2005 23:37:39 -0800 (PST)
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From: Chris Leech <chris.leech@gmail.com>
Date: Tue, 20 Dec 2005 23:10:07 -0800

>  That could be a good way to deal with it.  Actually, I should double
> check the length of tcp_skb_cb.  I took a quick look and thought that
> there might be some room left there anyway, even though the comment in
> tcp.h says otherwise.

There isn't, it's basically full on 64-bit systems with ipv6 enabled.

Just put the DMA cookie object explicitly into struct sk_buff,
protected by CONFIG_NET_DMA.