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Date: Tue, 12 Mar 2024 22:28:44 +0100
From: Christoph Hellwig <hch@lst.de>
To: Leon Romanovsky <leon@kernel.org>
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Subject: Re: [RFC RESEND 00/16] Split IOMMU DMA mapping operation to two
 steps
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On Sun, Mar 10, 2024 at 11:35:13AM +0200, Leon Romanovsky wrote:
> And you will need to have a way to instruct that pin_user_pages() variant
> to continue anyway, because you asked for FOLL_PCI_P2PDMA. Without that
> force, you will have !FOLL_PCI_P2PDMA behaviour.

I don't understand what you mean.

> When you say "simplify the overall interface", which interface do you mean?

Primarily the dma mapping interface.  Secondarily also everything around
it.