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Date: Tue, 26 May 2026 08:46:29 +0200
From: Christoph Hellwig <hch@lst.de>
To: Qu Wenruo <wqu@suse.com>
Cc: dsterba@suse.cz, Christoph Hellwig <hch@lst.de>,
	linux-btrfs@vger.kernel.org, linux-raid@vger.kernel.org
Subject: Re: [PATCH 3/3] btrfs: disguise single-data-RAID56 as RAID1/RAID1C3
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On Mon, May 25, 2026 at 08:09:54PM +0930, Qu Wenruo wrote:
>> It's a lazy hack at best and fix on absolutely wrong layer. The library
>> should provide the support for the edge case. But we disagree on that.
>
> I strongly disagree.
>
> Firstly on the layer to fix, let me be clear, if something writes like 
> RAID1, reads like RAID1, repairs like RAID1, then it's RAID1.

*nod*

> With that mindset, changing chunk type at read/add time is exactly the 
> correct layer to fix.

It also is amazingly simple!