[PATCH v2 1/8] iommu: Refactor __iommu_domain_alloc()

[Vasant Hegde <vasant.hegde@amd.com>]

From: Jason Gunthorpe <jgg@ziepe.ca>

Following patch will introduce iommu_paging_domain_alloc_flags() API.
Hence move domain init code to separate function so that it can be
resued.

Also move iommu_get_dma_cookie() setup iommu_setup_default_domain() as
its required in DMA API mode only.

Signed-off-by: Jason Gunthorpe <jgg@ziepe.ca>
[Split the patch and added description - Vasant]
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
---
 drivers/iommu/iommu.c | 46 +++++++++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 21 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index ed6c5cb60c5a..4118d3b15310 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1934,6 +1934,22 @@ void iommu_set_fault_handler(struct iommu_domain *domain,
 }
 EXPORT_SYMBOL_GPL(iommu_set_fault_handler);
 
+static void iommu_domain_init(struct iommu_domain *domain, unsigned int type,
+			      const struct iommu_ops *ops)
+{
+	domain->type = type;
+	domain->owner = ops;
+	if (!domain->ops)
+		domain->ops = ops->default_domain_ops;
+
+	/*
+	 * If not already set, assume all sizes by default; the driver
+	 * may override this later
+	 */
+	if (!domain->pgsize_bitmap)
+		domain->pgsize_bitmap = ops->pgsize_bitmap;
+}
+
 static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops,
 						 struct device *dev,
 						 unsigned int type)
@@ -1962,27 +1978,7 @@ static struct iommu_domain *__iommu_domain_alloc(const struct iommu_ops *ops,
 	if (!domain)
 		return ERR_PTR(-ENOMEM);
 
-	domain->type = type;
-	domain->owner = ops;
-	/*
-	 * If not already set, assume all sizes by default; the driver
-	 * may override this later
-	 */
-	if (!domain->pgsize_bitmap)
-		domain->pgsize_bitmap = ops->pgsize_bitmap;
-
-	if (!domain->ops)
-		domain->ops = ops->default_domain_ops;
-
-	if (iommu_is_dma_domain(domain)) {
-		int rc;
-
-		rc = iommu_get_dma_cookie(domain);
-		if (rc) {
-			iommu_domain_free(domain);
-			return ERR_PTR(rc);
-		}
-	}
+	iommu_domain_init(domain, type, ops);
 	return domain;
 }
 
@@ -2965,6 +2961,14 @@ static int iommu_setup_default_domain(struct iommu_group *group,
 	if (group->default_domain == dom)
 		return 0;
 
+	if (iommu_is_dma_domain(dom)) {
+		ret = iommu_get_dma_cookie(dom);
+		if (ret) {
+			iommu_domain_free(dom);
+			return ret;
+		}
+	}
+
 	/*
 	 * IOMMU_RESV_DIRECT and IOMMU_RESV_DIRECT_RELAXABLE regions must be
 	 * mapped before their device is attached, in order to guarantee
-- 
2.31.1