nvme tcp receive errors

[Sagi Grimberg]

>> Hey Keith,
>>
>> Did this resolve the issues?
> 
> We're unfortunately still observing data digest issues even with this.
> Most of the testing has shifted to the r2t error, so I don't have any
> additional details on the data digest problem.

I've looked again at the code, and I'm not convinced that the patch
is needed at all anymore, I'm now surprised that it actually changed
anything (disregarding data digest).

The driver does not track the received bytes by definition, it relies
on the controller to send it a completion, or set the success flag in
the _last_ c2hdata pdu. Does your target set
NVME_TCP_F_DATA_SUCCESS on any of the c2hdata pdus?