Merge tag 'iommu-v4.15-rc3' of git://github.com/awilliam/linux-vfio

Pull IOMMU fix from Alex Williamson:
 "Fix VT-d handling of scatterlists where sg->offset exceeds PAGE_SIZE"

* tag 'iommu-v4.15-rc3' of git://github.com/awilliam/linux-vfio:
  iommu/vt-d: Fix scatterlist offset handling

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index a0babdbf71460dda5dc156bfe7b7b9313e0da679..4a2de34895ec3177eb07082afe46a8921fa9f958 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2250,10 +2250,12 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
                uint64_t tmp;
 
                if (!sg_res) {
+                       unsigned int pgoff = sg->offset & ~PAGE_MASK;
+
                        sg_res = aligned_nrpages(sg->offset, sg->length);
-                       sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;
+                       sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + pgoff;
                        sg->dma_length = sg->length;
-                       pteval = page_to_phys(sg_page(sg)) | prot;
+                       pteval = (sg_phys(sg) - pgoff) | prot;
                        phys_pfn = pteval >> VTD_PAGE_SHIFT;
                }
 
@@ -3787,7 +3789,7 @@ static int intel_nontranslate_map_sg(struct device *hddev,
 
        for_each_sg(sglist, sg, nelems, i) {
                BUG_ON(!sg_page(sg));
-               sg->dma_address = page_to_phys(sg_page(sg)) + sg->offset;
+               sg->dma_address = sg_phys(sg);
                sg->dma_length = sg->length;
        }
        return nelems;