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Date:   Mon, 10 Oct 2022 00:59:01 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Chaitanya Kulkarni <kch@nvidia.com>
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Subject: Re: [RFC PATCH 01/18] block: add and use init disk helper
Message-ID: <Y0PQxdzmMzAAW0KF@infradead.org>
References: <20221005050027.39591-1-kch@nvidia.com>
 <20221005050027.39591-2-kch@nvidia.com>
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Precedence: bulk

On Tue, Oct 04, 2022 at 10:00:10PM -0700, Chaitanya Kulkarni wrote:
> +void init_disk(struct gendisk *disk, int major, int first_minor,
> +		int minors, sector_t sectors, void *private_data,
> +		const struct block_device_operations *fops)
> +{
> +	disk->major = major;
> +	disk->first_minor = first_minor;
> +	disk->minors = minors;
> +	set_capacity(disk, sectors);
> +	disk->private_data = private_data;
> +	disk->fops = fops;

I don't like this at all.  For one major/first_minor/minors are
optional and discouraged for new drivers.  Setting the capacity is
a different thing and is done by helpers also used for revalidation
in many drivers.

It might make sense to pass the fops (and maybe private_data) to
blk_mq_alloc_disk / blk_alloc_disk, but even then I'm not quite
sure it is worth the churn.