[PATCH 2/5] block: add support for copy offload

[Christoph Hellwig]

On Tue, May 27, 2025 at 03:33:00PM -0600, Keith Busch wrote:
> >  - copy also needs to be handled by the zoned write plugs
> 
> This is about emulating "copy append" behavior for sequential zones? In
> case it gets split, we can't safely dispatch multiple copy operations
> targeting the same destination zone, right?

No, it's just about ensuring there is no multiple copies outatanding
that the HBA could reorder.  i.e.g just serialization.  The only thing
that should be needed is adding REQ_OP_COPY to the switch statement
in blk_zone_plug_bio and make it go into the blk_zone_wplug_handle_write
case.