xprtrdma: Enable swap-on-NFS/RDMA
xprtrdma: Enable swap-on-NFS/RDMA

After adding a swapfile on an NFS/RDMA mount and removing the
normal swap partition, I was able to push the NFS client well
into swap without any issue.

I forgot to swapoff the NFS file before rebooting. This pinned
the NFS mount and the IB core and provider, causing shutdown to
hang. I think this is expected and safe behavior. Probably
shutdown scripts should "swapoff -a" before unmounting any
filesystems.

Signed-off-by: Chuck Lever <e7d8216bf9b1956703857d0050bd04192118f43d@oracle.com>
Reviewed-by: Sagi Grimberg <380ce2a82d3d08e67ab163b51dc6d30288ad3f13@mellanox.com>
Tested-By: Devesh Sharma <16cc9eb711a83f850aacd9fc3ca2bd5f5ba2a6c6@avagotech.com>
Signed-off-by: Anna Schumaker <5381043123508d4eed62c465c7c46f2f193a2767@Netapp.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs