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Date:   Thu, 19 May 2022 12:50:23 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Qu Wenruo <wqu@suse.com>
Cc:     Christoph Hellwig <hch@lst.de>, Qu Wenruo <quwenruo.btrfs@gmx.com>,
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Subject: Re: [PATCH 12/15] btrfs: add new read repair infrastructure
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On Thu, May 19, 2022 at 06:41:52PM +0800, Qu Wenruo wrote:
> So in that case, the best solution is to use "btrfs-map-logical -l 
> 343998464", which will directly return the physical offset of the wanted 
> logical on each involved devices.
>
> Although we need to note:
>
> - btrfs-map-logical may not always be shipped in progs in the future
>   This tool really looks like a debug tool. I'm not sure if we will keep
>   shipping it (personally I really hope to)
>
> - btrfs-map-logical only return data stripes
>   Thus it doesn't work for RAID56 just in case you want to use it.
>
> Despite the weird extent logical bytenr, everything should be fine with 
> btrfs-map-logical.


Oh, nice, this is much better than the hackery in the existing tests.

That bein said the -c option does not seem to work.  No matter what
I specify it always returns all three mirrors.  I guess a little
awk will fix that, but the behavior seems odd.