intel-iommu: Fix integer wrap on 32 bit kernels

The following 64 bit promotions are necessary to handle memory above the
4GiB boundary correctly.

[dwmw2: Fix the second part not to need 64-bit arithmetic at all]

Signed-off-by: Benjamin LaHaise <ben.lahaise@neterion.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 5493c79..52026d1 100644 (file)
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -735,7 +735,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
                                return NULL;
 
                        domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE);
-                       pteval = (virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE;
+                       pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE;
                        if (cmpxchg64(&pte->val, 0ULL, pteval)) {
                                /* Someone else set it while we were thinking; use theirs. */
                                free_pgtable_page(tmp_page);
@@ -2648,10 +2648,9 @@ static void flush_unmaps(void)
                        unsigned long mask;
                        struct iova *iova = deferred_flush[i].iova[j];
 
-                       mask = (iova->pfn_hi - iova->pfn_lo + 1) << PAGE_SHIFT;
-                       mask = ilog2(mask >> VTD_PAGE_SHIFT);
+                       mask = ilog2(mm_to_dma_pfn(iova->pfn_hi - iova->pfn_lo + 1));
                        iommu_flush_dev_iotlb(deferred_flush[i].domain[j],
-                                       iova->pfn_lo << PAGE_SHIFT, mask);
+                                       (uint64_t)iova->pfn_lo << PAGE_SHIFT, mask);
                        __free_iova(&deferred_flush[i].domain[j]->iovad, iova);
                }
                deferred_flush[i].next = 0;