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Date:   Fri, 15 Sep 2023 20:50:59 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Pankaj Raghav <kernel@pankajraghav.com>
Cc:     linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
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        djwong@kernel.org, linux-mm@kvack.org, chandan.babu@oracle.com,
        mcgrof@kernel.org, gost.dev@samsung.com
Subject: Re: [RFC 08/23] filemap: align the index to mapping_min_order in
 filemap_get_folios_tag()
Message-ID: <ZQS1o38TOOI+AY5H@casper.infradead.org>
References: <20230915183848.1018717-1-kernel@pankajraghav.com>
 <20230915183848.1018717-9-kernel@pankajraghav.com>
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On Fri, Sep 15, 2023 at 08:38:33PM +0200, Pankaj Raghav wrote:
> From: Luis Chamberlain <mcgrof@kernel.org>
> 
> Align the index to the mapping_min_order number of pages while setting
> the XA_STATE in filemap_get_folios_tag().

... because?  It should already search backwards in the page cache,
otherwise calling sync_file_range() would skip the start if it landed
in a tail page of a folio.