net: add paged frag destructor support to kernel_sendpage.
From: Ian Campbell <email@example.com>
Date: Thu, 5 Jan 2012 17:13:43 +0000
> -static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset,
> +static ssize_t do_tcp_sendpages(struct sock *sk,
> + struct page **pages,
> + struct skb_frag_destructor **destructors,
> + int poffset,
> size_t psize, int flags)
> struct tcp_sock *tp = tcp_sk(sk);
An array of destructors is madness, and the one call site that specifies this
passes an address of a single entry.
This also would never even have to occur if you put the destructor inside of
struct page instead.
Finally, except for the skb_shared_info() layout optimization in patch #1 which
I alreayd applied, this stuff is not baked enough for the 3.3 merge window.