Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <622d87eb-f189-a2f0-281e-a0d4c1a04293@samsung.com>
Date:   Wed, 4 May 2022 10:38:50 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
        Thunderbird/91.8.1
Subject: Re: [PATCH 05/16] nvme: zns: Allow ZNS drives that have
 non-power_of_2 zone size
Content-Language: en-US
To:     Bart Van Assche <bvanassche@acm.org>, <jaegeuk@kernel.org>,
        <axboe@kernel.dk>, <snitzer@kernel.org>, <hch@lst.de>,
        <mcgrof@kernel.org>, <naohiro.aota@wdc.com>, <sagi@grimberg.me>,
        <damien.lemoal@opensource.wdc.com>, <dsterba@suse.com>,
        <johannes.thumshirn@wdc.com>
CC:     <linux-kernel@vger.kernel.org>, <linux-btrfs@vger.kernel.org>,
        <clm@fb.com>, <gost.dev@samsung.com>, <chao@kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>, <josef@toxicpanda.com>,
        <jonathan.derrick@linux.dev>, <agk@redhat.com>,
        <kbusch@kernel.org>, <kch@nvidia.com>,
        <linux-nvme@lists.infradead.org>, <dm-devel@redhat.com>,
        <jiangbo.365@bytedance.com>, <linux-fsdevel@vger.kernel.org>,
        <matias.bjorling@wdc.com>, <linux-block@vger.kernel.org>
From:   Pankaj Raghav <p.raghav@samsung.com>
In-Reply-To: <1e3afa38-0652-0a6a-045c-79a0b9c19f30@acm.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
CMS-TYPE: 201P
References: <20220427160255.300418-1-p.raghav@samsung.com>
        <CGME20220427160301eucas1p147d0dced70946e20dd2dd046b94b8224@eucas1p1.samsung.com>
        <20220427160255.300418-6-p.raghav@samsung.com>
        <1e3afa38-0652-0a6a-045c-79a0b9c19f30@acm.org>
Precedence: bulk


On 2022-05-03 18:50, Bart Van Assche wrote:
> On 4/27/22 09:02, Pankaj Raghav wrote:
>> -    sector &= ~(ns->zsze - 1);
>> +    sector = rounddown(sector, ns->zsze);
> 
> The above change breaks 32-bit builds since ns->zsze is 64 bits wide and
> since rounddown() uses the C division operator instead of div64_u64().
> 
Good catch. I don't see any generic helper for rounddown that will work
for both 32 bits and 64 bits. Maybe I will open code the rounddown logic
here so that it works for both 32 and 64 bits.
> Thanks,
> 
> Bart.