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Date:   Thu, 20 Jul 2023 23:31:06 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Daniel Golle <daniel@makrotopia.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Jens Axboe <axboe@kernel.dk>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Dave Chinner <dchinner@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Thomas =?iso-8859-1?Q?Wei=DFschuh?= <linux@weissschuh.net>,
        Jan Kara <jack@suse.cz>, Damien Le Moal <dlemoal@kernel.org>,
        Ming Lei <ming.lei@redhat.com>, Min Li <min15.li@samsung.com>,
        Christian Loehle <CLoehle@hyperstone.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
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        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mmc@vger.kernel.org, linux-mtd@lists.infradead.org
Subject: Re: [RFC PATCH 6/6] block: implement NVMEM provider
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On Thu, Jul 20, 2023 at 05:02:32PM +0100, Daniel Golle wrote:
> On Thu, Jul 20, 2023 at 12:04:43AM -0700, Christoph Hellwig wrote:
> > The layering here is exactly the wrong way around.  This block device
> > as nvmem provide has not business sitting in the block layer and being
> > keyed ff the gendisk registration.  Instead you should create a new
> > nvmem backed that opens the block device as needed if it fits your
> > OF description without any changes to the core block layer.
> > 
> 
> Ok. I will use a class_interface instead.

I'm not sure a class_interface makes much sense here.  Why does the
block layer even need to know about you using a device a nvmem provider?
As far as I can tell your provider should layer entirely above the
block layer and not have to be integrated with it.