Re: [RFC RESEND 00/16] Split IOMMU DMA mapping operation to two steps

Leon Romanovsky
2024-03-22T17:46:21Z

On Thu, Mar 21, 2024 at 11:40:13PM +0100, Christoph Hellwig wrote:
> On Wed, Mar 20, 2024 at 10:55:36AM +0200, Leon Romanovsky wrote:
> > Something like this will do the trick.
>
> As far as I can tell it totally misses the point. Which is not to never
> return non-P2P if the flag is set, but to return either all P2P or non-P2
> P and not create a boundary in the single call.

You are treating FOLL_PCI_P2PDMA as a hint, but in iov_iter_extract_user_pages()
you set it only for p2p queues. I was under impression that you want only p2p pages
in these queues.

Anyway, I can prepare other patch that will return or p2p or non-p2p pages in one shot.

Thanks