[GIT PULL] nvme update for Linux 4.14, take 2

[Sagi Grimberg]

>> If we get to choose, my preference would be to restore the old behavior
>> because currently existing nvme transports keep their internal ctrl
>> representation in the tagset->driver_data as they implement
>> init/exit_request. Bouncing in nvme core would require to change that
>> and always keep struct nvme_ctrl as the tagset->driver_data and convert
>> it on every handler...
>>
>> Everything is doable but it seems like an unneeded hassle to me...
> 
> Sorry but I'm not convinced that it would be necessary to change what
> tagset->driver_data points at. How about moving blk_mq_reinit_tagset() from
> the block layer core to the NVMe core, to rename it and to pass a pointer
> to the nvme_ctrl data structure to that function instead of only block layer
> information?

That would mean that I need to open-code the tagset iteration in nvme
which does not feel like something a driver should do.