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To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
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Subject: Re: Any bio_clone_slow() implementation which doesn't share
 bi_io_vec?
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On Wed, Nov 24, 2021 at 02:18:00PM +0800, Qu Wenruo wrote:
> Just so simple? Then that's super awesome.
> 
> But I'm a little concerned about the bio_add_hw_page() call in
> bio_add_zoned_append().
> 
> It's not exactly the same as bio_add_page().
> 
> Does it mean as long as our splitted bio doesn't exceed zone limit, we
> can do the convert without any further problem?

You need to look at the limits when splitting.  I have modified
blk_bio_segment_split and exported it to deal with that.  Let me split
those changes out cleanly and push out a branch.