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Date: Wed, 06 May 2015 11:59:51 -0500
From: Alan Cox <alc@rice.edu>
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To: Gleb Smirnoff <glebius@FreeBSD.org>, kib@FreeBSD.org, alc@FreeBSD.org
CC: arch@FreeBSD.org
Subject: Re: more strict KPI for vm_pager_get_pages()
References: <20150430142408.GS546@nginx.com>
 <20150506114549.GS34544@FreeBSD.org>
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On 05/06/2015 06:45, Gleb Smirnoff wrote:
>   Hi!
>
>   I'm splitting the patch into a serie. This is step 1:
>
> Pagers are responsible to update the array of pages in
> case if they replace pages in an object. All array entries
> must be valid, if pager returns VM_PAGER_OK.
>
> Note: the only pager that replaces pages is sg_pager, and
> it does that correctly.
>

No, look again, e.g., device_pager.