[PATCH 2/6] iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute

[Joerg Roedel <joerg.roedel@amd.com>]

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

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 drivers/iommu/amd_iommu.c |    4 ++++
 drivers/iommu/iommu.c     |   19 ++++++++++++++++---
 include/linux/iommu.h     |    8 ++++++++
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index f75e060..aa90be3 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3033,6 +3033,10 @@ 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 ef54718..3d0b0bf 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -345,10 +345,23 @@ 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 8b66e84..ba77bf9 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -37,16 +37,24 @@ struct iommu_domain;
 typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
 				struct device *, unsigned long, int);
 
+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;
+	struct iommu_domain_geometry geometry;
 };
 
 #define IOMMU_CAP_CACHE_COHERENCY	0x1
 #define IOMMU_CAP_INTR_REMAP		0x2	/* isolates device intrs */
 
 enum iommu_attr {
+	DOMAIN_ATTR_GEOMETRY,	/* struct iommu_domain_geometry */
 	DOMAIN_ATTR_MAX,
 };
 
-- 
1.7.5.4