iommu: Handle translated device firmware mappings

Signed-off-by: Janne Grunau <j@jannau.net>

Author: jannau

drivers/iommu/iommu.c

@@ -1188,21 +1188,29 @@ static int iommu_create_device_fw_mappings(struct iommu_domain *domain,
 
 	/* We need to consider overlapping regions for different devices */
 	list_for_each_entry(entry, &mappings, list) {
-		dma_addr_t start, end, addr;
+		dma_addr_t start, end, addr, iova;
 		size_t map_size = 0;
 
 		if (entry->type == IOMMU_RESV_DIRECT)
 			dev->iommu->require_direct = 1;
+		if (entry->type == IOMMU_RESV_TRANSLATED)
+			dev->iommu->require_translated = 1;
 
 		if ((entry->type != IOMMU_RESV_DIRECT &&
-		     entry->type != IOMMU_RESV_DIRECT_RELAXABLE) ||
+		     entry->type != IOMMU_RESV_DIRECT_RELAXABLE &&
+		     entry->type != IOMMU_RESV_TRANSLATED) ||
 		    !iommu_is_dma_domain(domain))
 			continue;
 
 		start = ALIGN(entry->start, pg_size);
 		end   = ALIGN(entry->start + entry->length, pg_size);
 
-		for (addr = start; addr <= end; addr += pg_size) {
+		if (entry->type == IOMMU_RESV_TRANSLATED)
+			iova = ALIGN(entry->dva, pg_size);
+		else
+			iova = start;
+
+		for (addr = start; addr <= end; addr += pg_size, iova += pg_size) {
 			phys_addr_t phys_addr;
 
 			if (addr == end)
@@ -1212,15 +1220,15 @@ static int iommu_create_device_fw_mappings(struct iommu_domain *domain,
 			 * Return address by iommu_iova_to_phys for 0 is
 			 * ambiguous. Offset to address 1 if addr is 0.
 			 */
-			phys_addr = iommu_iova_to_phys(domain, addr ? addr : 1);
+			phys_addr = iommu_iova_to_phys(domain, iova ? iova : 1);
 			if (!phys_addr) {
 				map_size += pg_size;
 				continue;
 			}
 
 map_end:
 			if (map_size) {
-				ret = iommu_map(domain, addr - map_size,
+				ret = iommu_map(domain, iova - map_size,
 						addr - map_size, map_size,
 						entry->prot, GFP_KERNEL);
 				if (ret)
@@ -2323,6 +2331,19 @@ static int __iommu_device_set_domain(struct iommu_group *group,
 			 "Firmware has requested this device have a 1:1 IOMMU mapping, rejecting configuring the device without a 1:1 mapping. Contact your platform vendor.\n");
 		return -EINVAL;
 	}
+	/*
+	 * If the device requires IOMMU_RESV_TRANSLATED then we cannot allow
+	 * the identy or blocking domain to be attached as it does not contain
+	 * the required translated mapping.
+	 */
+	if (dev->iommu->require_translated &&
+	    (new_domain->type == IOMMU_DOMAIN_IDENTITY ||
+	     new_domain->type == IOMMU_DOMAIN_BLOCKED ||
+	     new_domain == group->blocking_domain)) {
+		dev_warn(dev,
+			 "Firmware has requested this device have a translated IOMMU mapping, rejecting configuring the device without a translated mapping. Contact your platform vendor.\n");
+		return -EINVAL;
+	}
 
 	if (dev->iommu->attach_deferred) {
 		if (new_domain == group->default_domain)

include/linux/iommu.h

@@ -845,6 +845,7 @@ struct iommu_fault_param {
  * @pci_32bit_workaround: Limit DMA allocations to 32-bit IOVAs
  * @require_direct: device requires IOMMU_RESV_DIRECT regions
  * @shadow_on_flush: IOTLB flushes are used to sync shadow tables
+ * @require_translated: device requires IOMMU_RESV_TRANSLATED regions
  *
  * TODO: migrate other per device data pointers under iommu_dev_data, e.g.
  *	struct iommu_group	*iommu_group;
@@ -860,6 +861,7 @@ struct dev_iommu {
 	u32				pci_32bit_workaround:1;
 	u32				require_direct:1;
 	u32				shadow_on_flush:1;
+	u32				require_translated:1;
 };
 
 int iommu_device_register(struct iommu_device *iommu,