[PATCH] nfsd4: block metadata ops during grace period

We currently return err_grace if a user attempts a non-reclaim open during the
grace period.  But we also need to prevent renames and removes, at least, to
ensure clients have the chance to recover state on files before they are moved
or deleted.

Of course, local users could also do renames and removes during the lease
period, and there's not much we can do about that.  This at least will help
with remote users.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>