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From: Benjamin Coddington <bcodding@redhat.com>
To: David Howells <dhowells@redhat.com>
Cc: Gao Xiang <xiang@kernel.org>, Jeff Layton <jlayton@kernel.org>,
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Subject: Re: Roadmap for netfslib and local caching (cachefiles)
Date: Thu, 25 Jan 2024 14:28:46 -0500
Message-ID: <EB613778-D963-438B-AA20-66D5E5E0DD90@redhat.com>
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On 25 Jan 2024, at 10:07, David Howells wrote:

> Benjamin Coddington <bcodding@redhat.com> wrote:
>
>>> NFS.  NFS at the very least needs to be altered to give up the use of
>>> PG_private_2.
>>
>> Forgive what may be a naive question, but where is NFS using PG_private_2?
>
> aka PG_fscache.
>
> See nfs_fscache_release_folio() for example where it uses folio_test_fscache()
> and folio_wait_fscache().

Ah, thanks!  At the end of the netfslib work, will NFS still be able to
utilize fscache and still manage its own folios, or are you looking at
making fscache be an all-or-nothing depending on the use of netfslib?

I think NFS might easily stop using PG_fscache by carrying that information on
folio->private (since we're currently stuck with it).

Ben