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Message-ID: <d7004ae9-ad68-cb61-9ca8-0bf61efa0c21@acm.org>
Date:   Wed, 28 Sep 2022 11:13:28 -0700
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Subject: Re: [PATCH v15 11/13] dm: call dm_zone_endio after the target endio
 callback for zoned devices
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To:     Pankaj Raghav <p.raghav@samsung.com>, snitzer@kernel.org,
        axboe@kernel.dk, agk@redhat.com, hch@lst.de,
        damien.lemoal@opensource.wdc.com
Cc:     jaegeuk@kernel.org, gost.dev@samsung.com,
        linux-kernel@vger.kernel.org, hare@suse.de,
        matias.bjorling@wdc.com, Johannes.Thumshirn@wdc.com,
        linux-block@vger.kernel.org, linux-nvme@lists.infradead.org,
        pankydev8@gmail.com, dm-devel@redhat.com
References: <20220923173618.6899-1-p.raghav@samsung.com>
 <CGME20220923173631eucas1p23cceb8438d6b8b9c3460192c0ad2472d@eucas1p2.samsung.com>
 <20220923173618.6899-12-p.raghav@samsung.com>
From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <20220923173618.6899-12-p.raghav@samsung.com>
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On 9/23/22 10:36, Pankaj Raghav wrote:
> dm_zone_endio() updates the bi_sector of orig bio for zoned devices that
> uses either native append or append emulation, and it is called before the
> endio of the target. But target endio can still update the clone bio
> after dm_zone_endio is called, thereby, the orig bio does not contain
> the updated information anymore.
> 
> Currently, this is not a problem as the targets that support zoned devices
> such as dm-zoned, dm-linear, and dm-crypt do not have an endio function,
> and even if they do (such as dm-flakey), they don't modify the
> bio->bi_iter.bi_sector of the cloned bio that is used to update the
> orig_bio's bi_sector in dm_zone_endio function.
> 
> This is a prep patch for the new dm-po2zoned target as it modifies
> bi_sector in the endio callback.
> 
> Call dm_zone_endio for zoned devices after calling the target's endio
> function.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>