[RFC] Reinstate NFS exportability for JFFS2.

[Christoph Hellwig]

On Thu, May 01, 2008 at 08:42:59PM +0100, David Woodhouse wrote:
> On top of commit 27c72b040c0be8f3704ed0b6b84c12cbba24a7e8 (in the
> mtd-2.6 tree if Linus hasn't pulled it yet), this provides
> export_operations for JFFS2. 
> 
> It doesn't yet solve the readdirplus deadlock described in
> http://lists.infradead.org/pipermail/linux-mtd/2007-March/017663.html 
> 
> You also still need to set fsid manually when exporting it -- I'm
> thinking of adding a 'get_fsid' to the export_operations to allow the
> filesystem to provide its own...

Yes, and get_fsid would be extremly useful, especially for those
filesystems that already have an uuid in the superblock
(*cough*, XFS, *cough*), but it'll need some co-operations with
nfs-utils on when to use it.

Patch looks good for me except for the few introduced overlong lines.