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Date:   Mon, 27 Mar 2023 16:35:28 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <wqu@suse.com>
Cc:     linux-btrfs@vger.kernel.org, David Sterba <dsterba@suse.com>
Subject: Re: [PATCH v5 03/13] btrfs: introduce a new helper to submit read
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On Tue, Mar 28, 2023 at 07:30:53AM +0800, Qu Wenruo wrote:
> The new helper, btrfs_submit_scrub_read(), would be mostly a subset of
> btrfs_submit_bio(), with the following limitations:
> 
> - Only supports read
> - @mirror_num must be > 0
> - No read-time repair nor checksum verification
> - The @bbio must not cross stripe boundary
> 
> This would provide the basis for unified read repair for scrub, as we no
> longer needs to handle RAID56 recovery all by scrub, and RAID56 data
> stripes scrub can share the same code of read and repair.
> 
> The repair part would be the same as non-RAID56, as we only need to try
> the next mirror.

Stupid question: what do we actually still need this and the write helper
for now that I think the generic helpers should work just fine without
bbio->inode?