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Date: Tue, 7 Nov 2023 23:52:18 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Christian Brauner <brauner@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>,
	Christoph Hellwig <hch@infradead.org>,
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	Chris Mason <clm@fb.com>, David Sterba <dsterba@suse.com>,
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Subject: Re: [PATCH 0/3] fanotify support for btrfs sub-volumes
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On Tue, Nov 07, 2023 at 10:06:18AM +0100, Christian Brauner wrote:
> > But it doesn't appear to me there's agreement on the way forward.  vfsmounts
> > aren't going to do anything from what I can tell, but I could very well be
> > missing some detail.  And Christian doesn't seem to want that as a solution.
> 
> No, I really don't.
> 
> I still think that it is fine to add a statx() flag indicating that a
> file is located on a subvolume. That allows interested userspace to
> bounce to an ioctl() where you can give it additional information in
> whatever form you like.

What is that flag going to buy us?