nfsv4 server patches and status

[Jeff Layton]

On Tue, 10 Jul 2007 11:12:55 -0400
"J. Bruce Fields" <bfields at fieldses.org> wrote:

> On Tue, Jul 10, 2007 at 11:08:38AM -0400, Jeff Layton wrote:
> > I've been looking over this problem a bit and have a sparse few
> > brainstorming notes in the following RH BZ:
> > 
> > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=237108
> > 
> > I've checked out Bryce's work above. I'm curious as to why he decided
> > to use a loopback mount here rather than something simple like tmpfs?
> > In some cursory checking, tmpfs seems to work fine when exported with a
> > fsid, and for this we know it would be exported with fsid=0.
> 
> It would be nice if we could use something like tmpfs instead.  Is there
> any way to get it to give out stable filehandles?  We could just declare
> the filehandles to be volatile, but I don't think clients deal well with
> volatile filehandles in practice.
> 
> We don't really need to handle renames on the pseudofilesystem, so it'd
> be sufficient if it'd just give us the same filehandle as long as the
> path name stayed the same.
> 

Ahh, I wasn't thinking about that...

The inode numbers would be stable for the life of the tmpfs filesystem,
but they could easily change on reboot (or if a dir was removed
and recreated). If that's unacceptable then tmpfs is probably not
usable for this, especially if we can't really use volatile fh's.

Back to pondering other options :-)

Thanks,
-- 
Jeff Layton <jlayton at redhat.com>