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Date: Tue, 7 Nov 2023 10:06:18 +0100
From: Christian Brauner <brauner@kernel.org>
To: Josef Bacik <josef@toxicpanda.com>
Cc: Christoph Hellwig <hch@infradead.org>,
	Qu Wenruo <quwenruo.btrfs@gmx.com>,
	Amir Goldstein <amir73il@gmail.com>, Jan Kara <jack@suse.cz>,
	Chris Mason <clm@fb.com>, David Sterba <dsterba@suse.com>,
	linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 0/3] fanotify support for btrfs sub-volumes
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In-Reply-To: <20231106224210.GA3812457@perftesting>

> 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.