On Fri, Jul 09, 2021 at 12:35:01PM +0900, David Stevens wrote: > From: David Stevens <steve...@chromium.org> > > If SKIP_CPU_SYNC isn't already set, then iommu_dma_unmap_(page|sg) has > already called iommu_dma_sync_(single|sg)_for_cpu, so there is no need > to copy from the bounce buffer again. > > Signed-off-by: David Stevens <steve...@chromium.org> > --- > drivers/iommu/dma-iommu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index e79e274d2dc5..0a9a9a343e64 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -505,7 +505,8 @@ static void __iommu_dma_unmap_swiotlb(struct device *dev, > dma_addr_t dma_addr, > __iommu_dma_unmap(dev, dma_addr, size); > > if (unlikely(is_swiotlb_buffer(phys))) > - swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); > + swiotlb_tbl_unmap_single(dev, phys, size, dir, > + attrs | DMA_ATTR_SKIP_CPU_SYNC); > }
I think it would be cleaner to drop DMA_ATTR_SKIP_CPU_SYNC in the callers once they've called iommu_dma_sync_*_for_cpu(). Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
