On Fri, Jul 05, 2024 at 07:58:06AM +0200, Christoph Hellwig wrote: > > This is exactly how dma_map_sg() works. > > Which dma_map_sg? swiotlb handling is implemented in the underlying > ops, dma-direct and dma-iommu specifically. > > dma-direct just iterates over the entries and calls dma_direct_map_page, > which does a per-entry decision to bounce based on > is_swiotlb_force_bounce, dma_capable and dma_kmalloc_needs_bounce. dma-direct is not going to have "use_iova" flag. Robin pointed to dma-iommu path. In that case the flow is dma_map_sg()->iommu_dma_map_sg()->dev_use_sg_swiotlb(). Thanks > >
