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Date: Fri, 21 Jan 2005 16:43:53 -0800
From: Andrew Morton <akpm@osdl.org>
To: Paul Mackerras <paulus@samba.org>
Cc: clameter@sgi.com, davem@davemloft.net, hugh@veritas.com,
       linux-ia64@vger.kernel.org, torvalds@osdl.org, linux-mm@kvack.org,
       linux-kernel@vger.kernel.org
Subject: Re: Extend clear_page by an order parameter
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Paul Mackerras <paulus@samba.org> wrote:
>
> A cluster of 2^n contiguous pages
>  isn't one page by any normal definition.

It is, actually, from the POV of the page allocator.  It's a "higher order
page" and is controlled by a struct page*, just like a zero-order page...