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Date:   Tue, 10 Jan 2023 00:46:45 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Andreas Gruenbacher <agruenba@redhat.com>
Cc:     Dave Chinner <dchinner@redhat.com>,
        Christoph Hellwig <hch@infradead.org>,
        "Darrick J . Wong" <djwong@kernel.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Matthew Wilcox <willy@infradead.org>,
        linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-ext4@vger.kernel.org, cluster-devel@redhat.com,
        Christoph Hellwig <hch@lst.de>
Subject: Re: [RFC v6 04/10] iomap: Add iomap_get_folio helper
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On Mon, Jan 09, 2023 at 01:46:42PM +0100, Andreas Gruenbacher wrote:
> We can handle that by adding a new IOMAP_NOCREATE iterator flag and
> checking for that in iomap_get_folio().  Your patch then turns into
> the below.

Exactly.  And as I already pointed out in reply to Dave's original
patch what we really should be doing is returning an ERR_PTR from
__filemap_get_folio instead of reverse-engineering the expected
error code.

The only big question is if we should apply Dave's patch first as a bug
fix before this series, and I suspect we should do that.