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Date: Wed, 6 May 2015 20:16:11 +0300
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Alan Cox <alc@rice.edu>
Cc: kib@FreeBSD.org, alc@FreeBSD.org, arch@FreeBSD.org
Subject: Re: more strict KPI for vm_pager_get_pages()
Message-ID: <20150506171611.GF56147@glebius.int.ru>
References: <20150430142408.GS546@nginx.com>
 <20150506114549.GS34544@FreeBSD.org> <554A4887.9080308@rice.edu>
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On Wed, May 06, 2015 at 11:59:51AM -0500, Alan Cox wrote:
A> > Pagers are responsible to update the array of pages in
A> > case if they replace pages in an object. All array entries
A> > must be valid, if pager returns VM_PAGER_OK.
A> >
A> > Note: the only pager that replaces pages is sg_pager, and
A> > it does that correctly.
A> >
A> 
A> No, look again, e.g., device_pager.

Yes, now I see it, it goes trough cdev op.

But it appears also to work correctly - it updates the page in the array.

-- 
Totus tuus, Glebius.