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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Fri, 30 Jul 2021 09:59:41 +0200
Message-ID: <CAJfpegub4oBZCBXFQqc8J-zUiSW+KaYZLjZaeVm_cGzNVpxj+A@mail.gmail.com>
Subject: Re: [PATCH 01/11] VFS: show correct dev num in mountinfo
To:     NeilBrown <neilb@suse.de>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        Josef Bacik <josef@toxicpanda.com>,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Chuck Lever <chuck.lever@oracle.com>, Chris Mason <clm@fb.com>,
        David Sterba <dsterba@suse.com>, linux-fsdevel@vger.kernel.org,
        Linux NFS list <linux-nfs@vger.kernel.org>,
        Btrfs BTRFS <linux-btrfs@vger.kernel.org>
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On Fri, 30 Jul 2021 at 09:34, NeilBrown <neilb@suse.de> wrote:

> But I'm curious about your reference to "some sort of subvolume
> structure that the VFS knows about".  Do you have any references, or can
> you suggest a search term I could try?

Found this:
https://lore.kernel.org/linux-fsdevel/20180508180436.716-1-mfasheh@suse.de/

I also remember discussing it at some LSF/MM with the btrfs devs, but
no specific conclusion.

Thanks,
Miklos