From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ram <linuxram@us.ibm.com>
Subject: Re: [PATCH] private mounts
Date: Mon, 25 Apr 2005 09:18:43 -0700
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Cc: Jan Hudec <bulb@ucw.cz>, Miklos Szeredi <miklos@szeredi.hu>,
	viro@parcelfarce.linux.theplanet.co.uk, hch@infradead.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	Andrew Morton <akpm@osdl.org>
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On Mon, 2005-04-25 at 08:17, Bodo Eggert  wrote:
> Jan Hudec <bulb@ucw.cz> wrote:
> > On Mon, Apr 25, 2005 at 11:58:50 +0200, Miklos Szeredi wrote:
> 
> >> How do you bind mount it from a different namespace?  You _do_ need
> >> bind mount, since a new mount might require password input, etc...
> > 
> > Yes, I would need one thing from kernel. That one thing would be to
> > mount bind a directory handle, instead of path.
> > 
> > And if you wonder how I get the handle, that's what SCM_RIGHTS message
> > of unix-domain sockets is for.
> 
> You'll need something to get the FD from. What will that be if the mount
> was done from a subshell of the midnight commander run in a screen session?
> 
> What about X sessions? Open a xterm, do the mount and then do what to get
> the mount working for the programs run from the window manager?
> Relogin? The xterm with the mount will be gone.
> Use a daemon to keep an additional reference to the namespace? That's UGLY.
> 
> With attachable namespaces, the whole thing should be as simple as
> (pseudocode)
> mknamespace -p users/$UID # (like mkdir -p)
> setnamespace users/$UID   # (like cd)
> 
> Optionally, the namespaces and their private mounts might be scheduled to
> be removed if the last user is gone, or they need to be persistent,
> depending on the applicaton (e.g. ssh used as rexec or shared mounts).

Agreed.

I guess for this thread to make any progress, we need a set of coherent
requirements from FUSE team.

RP