Hi.

Attached is a small patch to allow file systems to inform the file
system independent layers that they don't support file leases.

The problem is that some file system such as NFSv2 and NFSv3 do
not have sufficient support to be able to support leases correctly.
In particular for these two file systems, there is no over the wire
protocol support.

Currently, these two file systems fail the fcntl(F_SETLEASE) call
accidentally, due to a reference counting difference.  These file
systems should fail more consciously, with a proper error to
indicate that the call is invalid for them.

   Thanx...

      ps

Sign-off-by: Peter Staubach <staubach@redhat.com>