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Date:   Tue, 31 Mar 2020 11:49:30 +0200
From:   Karel Zak <kzak@redhat.com>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Christian Brauner <christian.brauner@ubuntu.com>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>, dray@redhat.com,
        Miklos Szeredi <mszeredi@redhat.com>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Jeff Layton <jlayton@redhat.com>, Ian Kent <raven@themaw.net>,
        andres@anarazel.de, keyrings@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Lennart Poettering <lennart@poettering.net>,
        Aleksa Sarai <cyphar@cyphar.com>
Subject: Re: Upcoming: Notifications, FS notifications and fsinfo()
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On Tue, Mar 31, 2020 at 10:56:35AM +0200, Miklos Szeredi wrote:
> I think we are approaching this from the wrong end.   Let's just
> ignore all of the proposed interfaces for now and only concentrate on
> what this will be used for.
> 
> Start with a set of use cases by all interested parties.  E.g.
> 
>  - systemd wants to keep track attached mounts in a namespace, as well
> as new detached mounts created by fsmount()
> 
>  - systemd need to keep information (such as parent, children, mount
> flags, fs options, etc) up to date on any change of topology or
> attributes.
> 
>  - util linux needs to display the topology and state of mounts in the
> system that corresponds to a consistent state that set of mounts

  - like systemd we also need in mount/umount to query one mountpoint
  rather than parse all /proc/self/mountinfo

 Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com