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Date:   Wed, 18 Jan 2023 17:43:58 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Brian Foster <bfoster@redhat.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>,
        Hugh Dickins <hughd@google.com>, linux-afs@lists.infradead.org,
        linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org,
        cluster-devel@redhat.com, linux-mm@kvack.org,
        linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-nilfs@vger.kernel.org
Subject: Re: [PATCH 4/9] shmem: remove shmem_get_partial_folio
Message-ID: <20230118164358.GD7584@lst.de>
References: <20230118094329.9553-1-hch@lst.de> <20230118094329.9553-5-hch@lst.de> <Y8f6sShghKuFim5E@bfoster>
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On Wed, Jan 18, 2023 at 08:57:05AM -0500, Brian Foster wrote:
> This all seems reasonable to me at a glance, FWIW, but I am a little
> curious why this wouldn't split up into two changes. I.e., switch this
> over to filemap_get_entry() to minimally remove the FGP_ENTRY dependency
> without a behavior change, then (perhaps after the next patch) introduce
> SGP_FIND in a separate patch. That makes it easier to review and
> potentially undo if it happens to pose a problem in the future. Hm?

The minimal change to filemap_get_entry would require to add the
lock, check mapping and retry loop and thus add a fair amount of
code.  So I looked for ways to avoid that and came up with this
version.  But if there is a strong preference to first open code
the logic and then later consolidate it I could do that.