[openib-general] CMA and device removal

[Roland Dreier]

    Sean> On creation, a cma_id is not bound to a particular device.
    Sean> It gets bound to a device as part of address resolution.
    Sean> The CMA tracks device references.  When a device is removed,
    Sean> the CMA will generate an event on all associated cma_id's.
    Sean> Users must destroy cma_id's and associated device resources
    Sean> after receiving the event.

I think this would require some modification of our current device
removal handling.  Currently we issue removal notifications in reverse
order of client registration -- in other words, the client that
registered last gets notified first.  This means that we don't notify
CMA of a device removal until after everyone using CMA has already
supposedly cleaned up.

 - R.