1. This version of the Portals LND is intended to work on the Cray XT3 using
   Cray Portals as a network transport.

2. To enable the building of the Portals LND (ptllnd.ko) configure with the
   following option:
   ./configure --with-portals=<path-to-portals-headers>

3. The following configuration options are supported

        ntx:
            The total number of message descritprs

        concurrent_peers:
            The maximum number of conncurent peers.  Peers attemting
            to connect beyond the maximum will not be allowd.

        peer_hash_table_size:
            The number of hash table slots for the peers. This number
            should scale with concurrent_peers.

        cksum:
            Set to non-zero to enable message (not RDMA) checksums for
            outgoing packets.   Incoming packets will always be checksumed
            if necssary, independnt of this value.

        timeout:
            The amount of time a request can linger in a peers active
            queue, before the peer is considered dead.  Units: seconds.

        portal:
            The portal ID to use for the ptllnd traffic.

        rxb_npages:
            The number of pages in a RX Buffer.

        credits:
            The maximum total number of concurrent sends that are
            outstanding at any given instant.

        peercredits:
            The maximum number of concurrent sends that are
            outstanding to a single piere at any given instant.

        max_msg_size:
            The maximum immedate message size.  This MUST be
            the same on all nodes in a cluster.  A peer connecting
            with a diffrent max_msg_size will be rejected.
