iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute

Implement the attribute itself and add the code for the
AMD IOMMU driver.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

3 files changed, 28 insertions, 3 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index a2e418cba0ff..259a6beddece 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3069,6 +3069,10 @@ static int amd_iommu_domain_init(struct iommu_domain *dom)
 
         dom->priv = domain;
 
+        dom->geometry.aperture_start = 0;
+        dom->geometry.aperture_end   = ~0ULL;
+        dom->geometry.force_aperture = true;
+
         return 0;
 
 out_free:
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index c39972d8ded3..ed5e0a553ca7 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -348,10 +348,23 @@ EXPORT_SYMBOL_GPL(iommu_device_group);
 int iommu_domain_get_attr(struct iommu_domain *domain,
                           enum iommu_attr attr, void *data)
 {
-        if (!domain->ops->domain_get_attr)
-                return -EINVAL;
+        struct iommu_domain_geometry *geometry;
+        int ret = 0;
+
+        switch (attr) {
+        case DOMAIN_ATTR_GEOMETRY:
+                geometry  = data;
+                *geometry = domain->geometry;
+
+                break;
+        default:
+                if (!domain->ops->domain_get_attr)
+                        return -EINVAL;
 
-        return domain->ops->domain_get_attr(domain, attr, data);
+                ret = domain->ops->domain_get_attr(domain, attr, data);
+        }
+
+        return ret;
 }
 EXPORT_SYMBOL_GPL(iommu_domain_get_attr);
 
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 0eef096183e8..f7df4aa527f3 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -37,11 +37,18 @@ struct iommu_domain;
 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
                         struct device *, unsigned long, int, void *);
 
+struct iommu_domain_geometry {
+        dma_addr_t aperture_start; /* First address that can be mapped    */
+        dma_addr_t aperture_end;   /* Last address that can be mapped     */
+        bool force_aperture;       /* DMA only allowed in mappable range? */
+};
+
 struct iommu_domain {
         struct iommu_ops *ops;
         void *priv;
         iommu_fault_handler_t handler;
         void *handler_token;
+        struct iommu_domain_geometry geometry;
 };
 
 #define IOMMU_CAP_CACHE_COHERENCY       0x1
@@ -49,6 +56,7 @@ struct iommu_domain {
 
 enum iommu_attr {
         DOMAIN_ATTR_MAX,
+        DOMAIN_ATTR_GEOMETRY,
 };
 
 #ifdef CONFIG_IOMMU_API