[PATCH] knfsd: nfsd4: simplify lease changing

The only way the protocol gives to change the lease time on the fly is to
simulate a reboot.  We don't have that completely right in the current code;
among other things, we should probably put lockd in grace too while we do
this.

For now, let's just keep this simple, and wait till the next time nfsd starts
to register any changes in lease time.  If the administrator really wants to
change the lease time *now*, they can go ahead and bring nfsd down and then
back up again after changing the lease time.

Also remove the "if (reclaim_str_hashtbl_size == 0)" case, a shortcut which
skips the grace period if we know of no clients in need of recovery.  This
isn't going to work well with nlm.

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>