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..
