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Date: Fri, 22 Mar 2024 19:46:17 +0200
From: Leon Romanovsky <leon@kernel.org>
To: Christoph Hellwig <hch@lst.de>
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Subject: Re: [RFC RESEND 00/16] Split IOMMU DMA mapping operation to two steps
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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