Re: [RFC 0/8] Copy Offload with Peer-to-Peer PCI Memory

From: Logan Gunthorpe
Date: Wed Apr 19 2017 - 14:41:45 EST




On 19/04/17 12:30 PM, Dan Williams wrote:
> Letting others users do the container_of() arrangement means that
> struct page_map needs to become public and move into struct
> dev_pagemap directly.

Ah, yes, I got a bit turned around by that and failed to notice that
page_map and dev_pagemap are different. Why is it that dev_pagemap
contains pretty much the exact same information as page_map? The only
thing gained that I can see is that the struct resource gains const
protection...

> ...I think that encapsulation loss is worth it for the gain of clearly
> separating the HMM-case from the base case.

Agreed.

Logan