[PATCHv2 2/2] nvme: use driver pdu command for passthrough

[Sagi Grimberg]

> All nvme transport drivers preallocate an nvme command for each request.
> Assume to use that command for nvme_setup_cmd() instead of requiring
> drivers pass a pointer to it. All nvme drivers must initialize the
> generic nvme_request 'cmd' to point to the transport's preallocated
> nvme_command.
> 
> The generic nvme_request cmd pointer had previously been used only as a
> temporary copy for passthrough commands. Since it now points to the
> command that gets dispatched, passthrough commands must directly set it
> up prior to executing the request.

This looks good,

Did you get to run blktests with this?