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From:   David Howells <dhowells@redhat.com>
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References: <30a4bd0e19626f5fb30f19f0ae70fba2debb361a.camel@kernel.org> <20220701022947.10716-1-xiubli@redhat.com> <20220701022947.10716-2-xiubli@redhat.com>
To:     Jeff Layton <jlayton@kernel.org>
Cc:     dhowells@redhat.com, xiubli@redhat.com, idryomov@gmail.com,
        vshankar@redhat.com, linux-kernel@vger.kernel.org,
        ceph-devel@vger.kernel.org, willy@infradead.org,
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Subject: Re: [PATCH 1/2] netfs: release the folio lock and put the folio before retrying
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Date:   Tue, 05 Jul 2022 14:21:24 +0100
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Jeff Layton <jlayton@kernel.org> wrote:

> I don't know here... I think it might be better to just expect that when
> this function returns an error that the folio has already been unlocked.
> Doing it this way will mean that you will lock and unlock the folio a
> second time for no reason.

I seem to remember there was some reason you wanted the folio unlocking and
putting.  I guess you need to drop the ref to flush it.

Would it make sense for ->check_write_begin() to be passed a "struct folio
**folio" rather than "struct folio *folio" and then the filesystem can clear
*folio if it disposes of the page?

David