Re: [PATCH -mm 5/7] add user namespace

[Al Boldi <a1426z@gawab.com>]

Trond Myklebust wrote:
> On Sat, 2006-07-15 at 06:35 -0600, Eric W. Biederman wrote:
> > I hope the confusion has passed for Trond.  My impression was he
> > figured this was per process data so it didn't make sense any where
> > near a filesystem, and the superblock was the last place it should
> > be.
>
> You are still using the wrong abstraction. Data that is not global to
> the entire machine has absolutely _no_ place being put into the
> superblock. It doesn't matter if it is process-specific,
> container-specific or whatever-else-specific, it will still be vetoed.
>
> If your real problem is uid/gid mapping on top of generic filesystems,
> then have you looked into the *BSD solution of using a stackable
> filesystem (i.e. umapfs)?

A stackable FS is really overkill here, when all that is needed is a simple 
mapping.  An easy solution would be, to allow for perMount Handlers via 
hooks into the VFS, as was suggested in the '[RFC] VFS: FS CoW using 
redirection' thread.

Thanks!

--
Al