Merge branch 'rds-assorted-bug-fixes'

Santosh Shilimkar says:

====================
RDS: Assorted bug fixes

We would like to improve RDS upstream support and in that context, I
started playing with it.  But run into number of issues including as
basic is RDS IB RDMA doesn't work. As part of the debug, I ended up
creating the $subject series which has bunch of assorted fixes. At
least with this series I can run RDS IB RDMA and other tests
successfully.

Some of these fixes have been done by Chris Meson, Andy Grover and
Zach Brown while at Oracle. There are still more kinks with FMR and
error handling and I plan to address them in a follow up series.

Series generated against Linus's master(v4.2-rc-7) but also applies
against next-next cleanly. Its tested on Oracle hardware with IB
fabric for both bcopy as well as RDMA mode. I don't have access
to iWARP hardware so any testing help on iWARP hardware appreciated.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>