On Sat, Mar 10, 2018 at 11:01:43PM +0800, Ming Lei wrote:

quoted

I really dislike this being open coded in drivers.  It really should
be helper chared with the blk-mq map building that drivers just use.

For now just have a low-level blk_pci_map_queues that
blk_mq_pci_map_queues, hpsa and megaraid can share.  In the long run
it might make sense to change the blk-mq callout to that low-level
prototype as well.

The way for selecting reply queue is needed for non scsi_mq too.

Which still doesn't prevent you from using a common helper.