Re: [PATCH 00/16] Add new DMA mapping operation for P2PDMA

From: John Hubbard
Date: Tue Apr 27 2021 - 16:22:05 EST

On 4/27/21 12:28 PM, Jason Gunthorpe wrote:
On Thu, Apr 08, 2021 at 11:01:07AM -0600, Logan Gunthorpe wrote:

This patchset continues my work to to add P2PDMA support to the common
dma map operations. This allows for creating SGLs that have both P2PDMA
and regular pages which is a necessary step to allowing P2PDMA pages in

The earlier RFC[1] generated a lot of great feedback and I heard no show
stopping objections. Thus, I've incorporated all the feedback and have
decided to post this as a proper patch series with hopes of eventually
getting it in mainline.

I'm happy to do a few more passes if anyone has any further feedback
or better ideas.

For the user of the DMA API the idea seems reasonable enough, the next
steps to integrate with pin_user_pages() seem fairly straightfoward

Was there no feedback on this at all?

oops, I meant to review this a lot sooner, because this whole p2pdma thing is
actually very interesting and important...somehow it slipped but I'll take
a look now.

John Hubbard