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From:   Christoph Hellwig <hch@lst.de>
To:     Luis Chamberlain <mcgrof@kernel.org>
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Subject: Re: [RFC PATCH 3/3] nvme: add the "debug" host driver
Message-ID: <20220203161534.GA15366@lst.de>
References: <f0e19ae4-b37a-e9a3-2be7-a5afb334a5c3@nvidia.com> <20220201102122.4okwj2gipjbvuyux@mpHalley-2> <alpine.LRH.2.02.2202011327350.22481@file01.intranet.prod.int.rdu2.redhat.com> <CGME20220201183359uscas1p2d7e48dc4cafed3df60c304a06f2323cd@uscas1p2.samsung.com> <alpine.LRH.2.02.2202011333160.22481@file01.intranet.prod.int.rdu2.redhat.com> <20220202060154.GA120951@bgt-140510-bm01> <20220203160633.rdwovqoxlbr3nu5u@garbanzo>
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On Thu, Feb 03, 2022 at 08:06:33AM -0800, Luis Chamberlain wrote:
> On Wed, Feb 02, 2022 at 06:01:13AM +0000, Adam Manzanares wrote:
> > BTW I think having the target code be able to implement simple copy without 
> > moving data over the fabric would be a great way of showing off the command.
> 
> Do you mean this should be implemented instead as a fabrics backend
> instead because fabrics already instantiates and creates a virtual
> nvme device? And so this would mean less code?

It would be a lot less code.  In fact I don't think we need any new code
at all.  Just using nvme-loop on top of null_blk or brd should be all
that is needed.