[PATCH 3/3] nvme: make SG_IO support optional

[Christoph Hellwig]

On Thu, Dec 24, 2015 at 12:39:40PM +0200, Sagi Grimberg wrote:
>
>> Translation SCSI commands to NVMe commands is rather pointless in general
>> as applications must not expext to be able to use SCSI commands on a
>> generic block device.
>>
>> Make the huge translation layer optional and hope no one will ever enable
>> it in the future.
>
> Umm, this is needed to support multipathing (at least in the multipath
> daemon current form). I'm not sure this is a good idea just yet...

It's not required, it's just you being lazy.  I defintivively want
to avoid people relying on this before actual multi path hardware
ships.  So feel free to enable it while you're lazy for now, but
I want people to disable it normally.