[RFC PATCH 2/7] block: don't merge different kinds of P2P transfers in a single bio

[Logan Gunthorpe]

On 2024-10-27 08:21, Leon Romanovsky wrote:
> From: Christoph Hellwig <hch at lst.de>
> 
> To get out of the dma mapping helpers having to check every segment for
> it's P2P status, ensure that bios either contain P2P transfers or non-P2P
> transfers, and that a P2P bio only contains ranges from a single device.
> 
> This means we do the page zone access in the bio add path where it should
> be still page hot, and will only have do the fairly expensive P2P topology
> lookup once per bio down in the dma mapping path, and only for already
> marked bios.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> Signed-off-by: Leon Romanovsky <leonro at nvidia.com>

Looks good to me.

Reviewed-by: Logan Gunthorpe <logang at deltatee.com>