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Date: Thu, 5 Jan 2017 18:43:38 +0100
From: David Sterba <dsterba@suse.cz>
To: Qu Wenruo <quwenruo@cn.fujitsu.com>
Cc: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH] btrfs: fix false enospc error when truncating heavily
 reflinked file
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On Wed, Jan 04, 2017 at 03:52:47PM +0800, Qu Wenruo wrote:
> Any comment on this patch?
> 
> Without it, btrfs will always fail for generic/387.

The fix looks good to me, adding it to next. There's a very similar
pattern in btrfs_punch_hole, but this function uses the trans reserve
and not truncate reserve. The modified reproducer does not trigger the
enospc, but it also could try harder.