[ofw] [RFC] [PATCH] winverbs: changes to support rdma_cm

[Sean Hefty]

>>         // IWVEndpoint methods
>> +       STDMETHOD(Modify)(
>> +               THIS_
>> +               __in DWORD Option,
>> +               __in_bcount_opt(OptionLength) const VOID* pOptionData,
>> +               __in SIZE_T OptionLength
>> +               ) PURE;
>> +
>
>What does Modify do?

Currently, it supports:

+#define WV_EP_OPTION_ROUTE                             0x00000001

which sets the path that a connection will use.  This lets the librdmacm call
into ibat for the PRs.

>> @@ -1202,8 +1236,7 @@
>>                 ) PURE;
>>
>>         STDMETHOD(Disconnect)(
>> -               THIS_
>> -               __in_opt OVERLAPPED* pOverlapped
>> +               THIS
>
>Is Disconnect just an EP function, or does it also change the underlying QP's
>state?  If the latter having it be an overlapped would be helpful.  If just a
>CM function, the QP Modify is still an overlapped (for flushing)?

Currently, disconnect is purely a CM function.  The QP modify call was unchanged
and has an overlapped structure.

I wasn't sure that disconnect should modify the QP.  If it doesn't then an app
can use disconnect to detach the send queue only, and let disconnect from the
peer detach the receive queue.  (Obviously, it's up to the app to enforce this
by not sending...) 

- Sean