[PATCH 4/7] nvme: implement multipath access to nvme subsystems

[Christoph Hellwig]

On Thu, Nov 09, 2017 at 04:22:17PM -0500, Mike Snitzer wrote:
> Your 0th header speaks to the NVMe multipath IO path leveraging NVMe's
> lack of partial completion but I think it'd be useful to have this
> header (that actually gets committed) speak to it.

There is a comment above blk_steal_bios to this respect, which is in
the tree.

> Also, the block core patch to introduce blk_steal_bios() already went in
> but should there be a QUEUE_FLAG that gets set by drivers like NVMe that
> don't support partial completion?
> 
> This would make it easier for other future drivers to know whether they
> can use a more optimized IO path.

As-is there is not real need for this.  But if you want to use a similar
path in dm-multipath feel free to add the flag when needed.