[linux-cifs-client] Multiple mounts on same mount points

[Jeff Layton]

On Tue, 01 Jun 2010 16:39:56 +0530
Suresh Jayaraman <sjayaraman at suse.de> wrote:

> On 05/31/2010 09:25 PM, Steve French wrote:
> > The existing MultiUserMount feature of cifs (this existing multiuser
> > support is more limited than what Jeff has proposed for the future)
> > required multiple mounts in order to pass unique credentials down for
> > each new uid.
> 
> Ok, thanks for the clarifying.
> 

Yes. We should note however that there's no real requirement with the
old multiuser support that the mounts all be to the same mountpoint. It
may be more convenient to do it that way in some situations however.

> 
> > Which local file systems allow multiple mounts to the same device on
> > same mount point?
> 
> I'm not aware of any such disk-based filesystem.
> 

There may be some, but in general it's discouraged in favor of bind
mounts...particularly now that you can do a r/o bind mount.

> > I think for the future it would be reasonable to forbid it (e.g. for
> > smb2 experimental code) assuming we have Jeff's multiuser support (or
> > something similar) implemented.
> 
> Sounds good.
> 

Agreed. What may be a good idea is that once that support goes in, to
have some patches that spew warnings that we're going to deprecate the
old multiuser mount code in a couple of releases. Then do so in that
timeframe. Forbidding this could be part of that deprecation process.

-- 
Jeff Layton <jlayton at samba.org>