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Date:   Mon, 27 Nov 2023 09:30:14 -0700
From:   Keith Busch <kbusch@kernel.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Daniel Wagner <dwagner@suse.de>, linux-nvme@lists.infradead.org,
        linux-kernel@vger.kernel.org, Sagi Grimberg <sagi@grimberg.me>,
        Hannes Reinecke <hare@suse.de>
Subject: Re: [RFC v1] nvme: add cse, ds, ms, nsze and nuse to sysfs
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On Mon, Nov 27, 2023 at 04:56:49PM +0100, Christoph Hellwig wrote:
> On Mon, Nov 27, 2023 at 08:44:52AM -0700, Keith Busch wrote:
> > > I'd probably spell out metadata_size, or probably even better
> > > metadata_bytes to match the unit postfixes elsewhere in the block code.
> > 
> > Should this even be an nvme specific attribute? I thought we should have
> > blk-integrity.c report its 'tuple_size' attribute instead. That should
> > work as long as we're not dealing with extended metadata at least, but
> > that's kind of a special format that doesn't have block layer support.
> 
> Reporting the tuple size is a good idea.  But is that enough for
> the existing nvme-cli use case?

nvme-cli currently queries with admin passthrough identify command, so
adding a new attribute won't break that. I assume Daniel would have it
fallback to that same command for backward compatibilty if a desired
sysfs attribute doesn't exist.