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Date: Mon, 24 May 2021 09:25:57 +0200
From: Christoph Hellwig <hch@lst.de>
To: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Chris Zankel <chris@zankel.net>, Max Filippov <jcmvbkbc@gmail.com>,
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	Mike Snitzer <snitzer@redhat.com>, Song Liu <song@kernel.org>,
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Subject: Re: [PATCH 13/26] dm: convert to blk_alloc_disk/blk_cleanup_disk
Message-ID: <20210524072557.GE23890@lst.de>
References: <20210521055116.1053587-1-hch@lst.de> <20210521055116.1053587-14-hch@lst.de> <de3b0976-1299-17d8-240a-2ecd8b9fbc2d@suse.de>
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On Sun, May 23, 2021 at 10:10:34AM +0200, Hannes Reinecke wrote:
> Can't these conditionals be merged into a single 'if (md->disk)'?
> Eg like:
>
> 	if (md->disk) {
> 		spin_lock(&_minor_lock);
> 		md->disk->private_data = NULL;
> 		spin_unlock(&_minor_lock);
> 		del_gendisk(md->disk);
> 		dm_queue_destroy_keyslot_manager(md->queue);
> 		blk_cleanup_disk(md->queue);
> 	}
>
> We're now always allocating 'md->disk' and 'md->queue' together,
> so how can we end up in a situation where one is set without the other?

I guess we could do that, not sure it is worth the churn, though.