iommu: Create direct mappings in default domains

Use the information exported by the IOMMU drivers to create
direct mapped regions in the default domains.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 6b8d6e7771e1..ffad1eaf450d 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -325,6 +325,52 @@ int iommu_group_set_name(struct iommu_group *group, const char *name)
 }
 EXPORT_SYMBOL_GPL(iommu_group_set_name);
 
+static int iommu_group_create_direct_mappings(struct iommu_group *group,
+                                              struct device *dev)
+{
+        struct iommu_domain *domain = group->default_domain;
+        struct iommu_dm_region *entry;
+        struct list_head mappings;
+        unsigned long pg_size;
+        int ret = 0;
+
+        if (!domain || domain->type != IOMMU_DOMAIN_DMA)
+                return 0;
+
+        BUG_ON(!domain->ops->pgsize_bitmap);
+
+        pg_size = 1UL << __ffs(domain->ops->pgsize_bitmap);
+        INIT_LIST_HEAD(&mappings);
+
+        iommu_get_dm_regions(dev, &mappings);
+
+        /* We need to consider overlapping regions for different devices */
+        list_for_each_entry(entry, &mappings, list) {
+                dma_addr_t start, end, addr;
+
+                start = ALIGN(entry->start, pg_size);
+                end   = ALIGN(entry->start + entry->length, pg_size);
+
+                for (addr = start; addr < end; addr += pg_size) {
+                        phys_addr_t phys_addr;
+
+                        phys_addr = iommu_iova_to_phys(domain, addr);
+                        if (phys_addr)
+                                continue;
+
+                        ret = iommu_map(domain, addr, addr, pg_size, entry->prot);
+                        if (ret)
+                                goto out;
+                }
+
+        }
+
+out:
+        iommu_put_dm_regions(dev, &mappings);
+
+        return ret;
+}
+
 /**
  * iommu_group_add_device - add a device to an iommu group
  * @group: the group into which to add the device (reference should be held)
@@ -381,6 +427,8 @@ rename:
 
         dev->iommu_group = group;
 
+        iommu_group_create_direct_mappings(group, dev);
+
         mutex_lock(&group->mutex);
         list_add_tail(&device->list, &group->devices);
         if (group->domain)