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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Fri, 28 Feb 2020 17:24:23 +0100
Message-ID: <CAJfpegsGgjnyZiB+ionfnnk+_e+5oaC-5nmGq+mLxWs1RcwsPw@mail.gmail.com>
Subject: Re: [PATCH 00/17] VFS: Filesystem information and notifications [ver #17]
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Ian Kent <raven@themaw.net>, Karel Zak <kzak@redhat.com>,
        Miklos Szeredi <mszeredi@redhat.com>,
        James Bottomley <James.Bottomley@hansenpartnership.com>,
        Steven Whitehouse <swhiteho@redhat.com>,
        David Howells <dhowells@redhat.com>,
        viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Jann Horn <jannh@google.com>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Lennart Poettering <lennart@poettering.net>,
        =?UTF-8?Q?Zbigniew_J=C4=99drzejewski=2DSzmek?= <zbyszek@in.waw.pl>,
        util-linux@vger.kernel.org
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On Fri, Feb 28, 2020 at 1:27 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:

> > Superblocks and mounts could get enumerated by a unique identifier.
> > mnt_id seems to be good for mounts, s_dev may or may not be good for
> > superblock, but  s_id (as introduced in this patchset) could be used
> > instead.
>
> So what would the sysfs tree look like with this?

For a start something like this:

mounts/$MOUNT_ID/
  parent -> ../$PARENT_ID
  super -> ../../supers/$SUPER_ID
  root: path from mount root to fs root (could be optional as usually
they are the same)
  mountpoint -> $MOUNTPOINT
  flags: mount flags
  propagation: mount propagation
  children/$CHILD_ID -> ../../$CHILD_ID

 supers/$SUPER_ID/
   type: fstype
   source: mount source (devname)
   options: csv of mount options

Thanks,
Miklos