Messages in this thread | | | Date | Thu, 29 Nov 2018 19:31:32 +0100 | From | Christoph Hellwig <> | Subject | Re: remove the ->mapping_error method from dma_map_ops V2 |
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On Thu, Nov 29, 2018 at 09:44:05AM -0800, Linus Torvalds wrote: > No. Really. If there's no iotlb, then you just mark that one page > reserved. It simply doesn't get used. It doesn't mean you suddenly > need a swiotlb.
Sure, we could just skip that page entirely based on dma_to_phys.
> But whatever. It's independent from the patch series under discussion. > Make dma_mapping_error() at least return a real error (eg -EINVAL, or > whatever is the common error), and we can maybe do this later.
Ok, I'll do that.
> Or, better yet, plan on removing the single-page dma mappign entirely > at a later date, and make the issue moot.
What would be the replacement? Build a S/G list for every single page mapping? Not sure that would create a lot of happy campers..
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