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Date:   Tue, 18 Aug 2020 10:39:36 -0700
From:   Keith Busch <kbusch@kernel.org>
To:     Javier Gonzalez <javier@javigon.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Kanchan Joshi <joshi.k@samsung.com>, Damien.LeMoal@wdc.com,
        axboe@kernel.dk, sagi@grimberg.me, linux-nvme@lists.infradead.org,
        linux-kernel@vger.kernel.org, johannes.thumshirn@wdc.com,
        Nitesh Shetty <nj.shetty@samsung.com>,
        SelvaKumar S <selvakuma.s1@samsung.com>
Subject: Re: [PATCH 2/2] nvme: add emulation for zone-append
Message-ID: <20200818173936.GA3097355@dhcp-10-100-145-180.wdl.wdc.com>
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On Tue, Aug 18, 2020 at 07:29:12PM +0200, Javier Gonzalez wrote:
> On 18.08.2020 09:58, Keith Busch wrote:
> > On Tue, Aug 18, 2020 at 11:50:33AM +0200, Javier Gonzalez wrote:
> > > a number of customers are requiring the use of normal writes, which we
> > > want to support.
> > 
> > A device that supports append is completely usable for those customers,
> > too. There's no need to create divergence in this driver.
> 
> Not really. You know as well as I do that some features are disabled for
> a particular SSD model on customer requirements. Generic models
> implementing append can submit both I/Os, but those that remove append
> are left out.

You are only supporting my point: if your device supports append, you
get to work in every ZNS use case, otherwise you only get to work in a
subset.