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Date: Tue, 12 Sep 2017 11:47:49 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Adam Borowski <kilobyte@angband.pl>
Cc: "Austin S. Hemmelgarn" <ahferroin7@gmail.com>, Marat Khalili <mkh@rqc.ru>,
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Subject: Re: qemu-kvm VM died during partial raid1 problems of btrfs
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On Tue, Sep 12, 2017 at 08:43:59PM +0200, Adam Borowski wrote:
> For now, though, I wonder -- should we send fine folks at util-linux a patch
> to make fallocate -d restore mtime, either always or on an option?

Don't do that.  Please just add a new ioctl or fallocate command
that punches a hole if the range is zeroed, similar to what dedup
does.  It can probably even reuse a few helpers.