[PATCH 07/12] nvme: special case AEN requests

[Christoph Hellwig]

On Mon, Nov 09, 2015 at 02:48:31PM -0700, Jens Axboe wrote:
> That fact is just implementation detail, I don't think we should make 
> assumptions about the range of reserved vs normal tags. That's just asking 
> for trouble if this changes at some point.

I'm pretty sure I did see another driver (hpsa patchset?) do this as well.
I can add a is_reserved_tag helper which still uses that knowledege, but
keeps it inside the block layer.