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Date: Sun, 28 Apr 2024 21:41:45 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Zhang Yi <yi.zhang@huaweicloud.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	"Darrick J. Wong" <djwong@kernel.org>, linux-xfs@vger.kernel.org,
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	tytso@mit.edu, jack@suse.cz, yi.zhang@huawei.com,
	chengzhihao1@huawei.com, yukuai3@huawei.com
Subject: Re: [PATCH v5 4/9] xfs: convert delayed extents to unwritten when
 zeroing post eof blocks
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On Sun, Apr 28, 2024 at 11:26:00AM +0800, Zhang Yi wrote:
> > 
> > Oh well.  Given that we're full in on the speculative allocations
> > we might as well deal with it.
> > 
> 
> Let me confirm, so you also think the preallocations in the COW fork that
> overlaps the unreflinked range is useless, we should avoid allocating
> this range, is that right? If so, I suppose we can do this improvement in
> another patch(set), this one works fine now.

Well, not stop allocating it, but not actually convert it to a real
allocation when we're just truncating it and replacing the blocks with
reflinked blocks.

But yes, this is a bigger project.

For now for this patch to go ahead:

Reviewed-by: Christoph Hellwig <hch@lst.de>