1 files changed, 27 insertions, 8 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index bba1b9f2f782..c1233d0288a0 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -464,7 +464,14 @@ static int iommu_init_device(struct device *dev)
 
 	dev_data->alias = get_alias(dev);
 
-	if (dev_is_pci(dev) && pci_iommuv2_capable(to_pci_dev(dev))) {
+	/*
+	 * By default we use passthrough mode for IOMMUv2 capable device.
+	 * But if amd_iommu=force_isolation is set (e.g. to debug DMA to
+	 * invalid address), we ignore the capability for the device so
+	 * it'll be forced to go into translation mode.
+	 */
+	if ((iommu_pass_through || !amd_iommu_force_isolation) &&
+	    dev_is_pci(dev) && pci_iommuv2_capable(to_pci_dev(dev))) {
 		struct amd_iommu *iommu;
 
 		iommu = amd_iommu_rlookup_table[dev_data->devid];
@@ -1889,6 +1896,7 @@ static void do_attach(struct iommu_dev_data *dev_data,
 
 static void do_detach(struct iommu_dev_data *dev_data)
 {
+	struct protection_domain *domain = dev_data->domain;
 	struct amd_iommu *iommu;
 	u16 alias;
 
@@ -1904,10 +1912,6 @@ static void do_detach(struct iommu_dev_data *dev_data)
 	iommu = amd_iommu_rlookup_table[dev_data->devid];
 	alias = dev_data->alias;
 
-	/* decrease reference counters */
-	dev_data->domain->dev_iommu[iommu->index] -= 1;
-	dev_data->domain->dev_cnt                 -= 1;
-
 	/* Update data structures */
 	dev_data->domain = NULL;
 	list_del(&dev_data->list);
@@ -1917,6 +1921,16 @@ static void do_detach(struct iommu_dev_data *dev_data)
 
 	/* Flush the DTE entry */
 	device_flush_dte(dev_data);
+
+	/* Flush IOTLB */
+	domain_flush_tlb_pde(domain);
+
+	/* Wait for the flushes to finish */
+	domain_flush_complete(domain);
+
+	/* decrease reference counters - needs to happen after the flushes */
+	domain->dev_iommu[iommu->index] -= 1;
+	domain->dev_cnt                 -= 1;
 }
 
 /*
@@ -2585,7 +2599,12 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
 
 	/* Everything is mapped - write the right values into s->dma_address */
 	for_each_sg(sglist, s, nelems, i) {
-		s->dma_address += address + s->offset;
+		/*
+		 * Add in the remaining piece of the scatter-gather offset that
+		 * was masked out when we were determining the physical address
+		 * via (sg_phys(s) & PAGE_MASK) earlier.
+		 */
+		s->dma_address += address + (s->offset & ~PAGE_MASK);
 		s->dma_length   = s->length;
 	}
 
@@ -2604,13 +2623,13 @@ out_unmap:
 			bus_addr  = address + s->dma_address + (j << PAGE_SHIFT);
 			iommu_unmap_page(domain, bus_addr, PAGE_SIZE);
 
-			if (--mapped_pages)
+			if (--mapped_pages == 0)
 				goto out_free_iova;
 		}
 	}
 
 out_free_iova:
-	free_iova_fast(&dma_dom->iovad, address, npages);
+	free_iova_fast(&dma_dom->iovad, address >> PAGE_SHIFT, npages);
 
 out_err:
 	return 0;