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To: Olivier Galibert <galibert@pobox.com>
Cc: "Hack inc." <linux-kernel@vger.kernel.org>
Subject: Re: alloc_pages and struct page *
References: <20050419105004.GA7612@dspnet.fr.eu.org>
From: Catalin Marinas <catalin.marinas@arm.com>
Date: Tue, 19 Apr 2005 13:06:50 +0100
In-Reply-To: <20050419105004.GA7612@dspnet.fr.eu.org> (Olivier Galibert's
 message of "Tue, 19 Apr 2005 12:50:04 +0200")
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Olivier Galibert <galibert@pobox.com> wrote:
> If I get a struct page * from a call to alloc_pages with a non-zero
> order, how do I get the struct page * of te following pages from the
> same allocation in order to use them in calls to tcp_sendpage?

page++;

The page structures are kept in an array, "mem_map" if
CONFIG_DISCONTIGMEM is not set or something like
"discontig_node_data[nid].node_mem_map" otherwise (this is true for
the ARM architecture, should be similar on the others). "alloc_pages"
allocates a contiguous range of pages from an array (and doesn't cross
a node boundary).

-- 
Catalin