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Subject: Re: [PATCH 0/4] eliminate SECTOR related magic numbers and duplicated
 conversions
To:     Zhen Lei <thunder.leizhen@huawei.com>,
        Minchan Kim <minchan@kernel.org>,
        Nitin Gupta <ngupta@vflare.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Jens Axboe <axboe@kernel.dk>,
        linux-block <linux-block@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>, Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@redhat.com>,
        dm-devel <dm-devel@redhat.com>, Song Liu <song@kernel.org>,
        linux-raid <linux-raid@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
References: <20200505115543.1660-1-thunder.leizhen@huawei.com>
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Date:   Tue, 5 May 2020 18:32:36 +0100
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On 05/05/2020 12:55, Zhen Lei wrote:
> When I studied the code of mm/swap, I found "1 << (PAGE_SHIFT - 9)" appears
> many times. So I try to clean up it.
> 
> 1. Replace "1 << (PAGE_SHIFT - 9)" or similar with SECTORS_PER_PAGE
> 2. Replace "PAGE_SHIFT - 9" with SECTORS_PER_PAGE_SHIFT
> 3. Replace "9" with SECTOR_SHIFT
> 4. Replace "512" with SECTOR_SIZE

Naive question - what is happening about 4096-byte sectors? Do we need 
to forward-plan?

Cheers,
Wol