[PATCH v1 05/20] iommu/amd: Implement test_dev callbacks to domain ops

[Nicolin Chen]

Move sanity and compatibility tests from the attach_dev callbacks to the
new test_dev callback functions. The IOMMU core makes sure an attach_dev
call must be invoked after a successful test_dev call.

Correct the errno upon malloc failure. Also, drop the function prototype
of iommu_sva_set_dev_pasid() from the header and make it static, as only
pasid.c uses it.

Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
---
 drivers/iommu/amd/amd_iommu.h |  3 ---
 drivers/iommu/amd/iommu.c     | 27 +++++++++++++++++++--------
 drivers/iommu/amd/pasid.c     | 29 +++++++++++++++++++----------
 3 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
index 9b4b589a54b57..f99fa4da34996 100644
--- a/drivers/iommu/amd/amd_iommu.h
+++ b/drivers/iommu/amd/amd_iommu.h
@@ -52,9 +52,6 @@ struct protection_domain *protection_domain_alloc(void);
 struct iommu_domain *amd_iommu_domain_alloc_sva(struct device *dev,
 						struct mm_struct *mm);
 void amd_iommu_domain_free(struct iommu_domain *dom);
-int iommu_sva_set_dev_pasid(struct iommu_domain *domain,
-			    struct device *dev, ioasid_t pasid,
-			    struct iommu_domain *old);
 void amd_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 				struct iommu_domain *domain);
 
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index e16ad510c8c8a..dc0406427dcf8 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -70,6 +70,8 @@ int amd_iommu_max_glx_val = -1;
  */
 DEFINE_IDA(pdom_ids);
 
+static int amd_iommu_test_device(struct iommu_domain *dom, struct device *dev,
+				 ioasid_t pasid, struct iommu_domain *old);
 static int amd_iommu_attach_device(struct iommu_domain *dom, struct device *dev,
 				   struct iommu_domain *old);
 
@@ -2670,6 +2672,7 @@ static struct iommu_domain blocked_domain = {
 static struct protection_domain identity_domain;
 
 static const struct iommu_domain_ops identity_domain_ops = {
+	.test_dev = amd_iommu_test_device,
 	.attach_dev = amd_iommu_attach_device,
 };
 
@@ -2686,12 +2689,26 @@ void amd_iommu_init_identity_domain(void)
 	protection_domain_init(&identity_domain);
 }
 
+static int amd_iommu_test_device(struct iommu_domain *dom, struct device *dev,
+				 ioasid_t pasid, struct iommu_domain *old)
+{
+	struct amd_iommu *iommu = get_amd_iommu_from_dev(dev);
+
+	/*
+	 * Restrict to devices with compatible IOMMU hardware support
+	 * when enforcement of dirty tracking is enabled.
+	 */
+	if (dom->dirty_ops && !amd_iommu_hd_support(iommu))
+		return -EINVAL;
+
+	return 0;
+}
+
 static int amd_iommu_attach_device(struct iommu_domain *dom, struct device *dev,
 				   struct iommu_domain *old)
 {
 	struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
 	struct protection_domain *domain = to_pdomain(dom);
-	struct amd_iommu *iommu = get_amd_iommu_from_dev(dev);
 	int ret;
 
 	/*
@@ -2703,13 +2720,6 @@ static int amd_iommu_attach_device(struct iommu_domain *dom, struct device *dev,
 
 	dev_data->defer_attach = false;
 
-	/*
-	 * Restrict to devices with compatible IOMMU hardware support
-	 * when enforcement of dirty tracking is enabled.
-	 */
-	if (dom->dirty_ops && !amd_iommu_hd_support(iommu))
-		return -EINVAL;
-
 	if (dev_data->domain)
 		detach_device(dev);
 
@@ -3047,6 +3057,7 @@ const struct iommu_ops amd_iommu_ops = {
 	.def_domain_type = amd_iommu_def_domain_type,
 	.page_response = amd_iommu_page_response,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
+		.test_dev	= amd_iommu_test_device,
 		.attach_dev	= amd_iommu_attach_device,
 		.map_pages	= amd_iommu_map_pages,
 		.unmap_pages	= amd_iommu_unmap_pages,
diff --git a/drivers/iommu/amd/pasid.c b/drivers/iommu/amd/pasid.c
index 77c8e9a91cbca..474494a66dd40 100644
--- a/drivers/iommu/amd/pasid.c
+++ b/drivers/iommu/amd/pasid.c
@@ -99,31 +99,39 @@ static const struct mmu_notifier_ops sva_mn = {
 	.release = sva_mn_release,
 };
 
-int iommu_sva_set_dev_pasid(struct iommu_domain *domain,
-			    struct device *dev, ioasid_t pasid,
-			    struct iommu_domain *old)
+static int iommu_sva_test_dev(struct iommu_domain *domain, struct device *dev,
+			      ioasid_t pasid, struct iommu_domain *old)
 {
-	struct pdom_dev_data *pdom_dev_data;
-	struct protection_domain *sva_pdom = to_pdomain(domain);
 	struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
-	unsigned long flags;
-	int ret = -EINVAL;
 
 	if (old)
 		return -EOPNOTSUPP;
 
 	/* PASID zero is used for requests from the I/O device without PASID */
 	if (!is_pasid_valid(dev_data, pasid))
-		return ret;
+		return -EINVAL;
 
 	/* Make sure PASID is enabled */
 	if (!is_pasid_enabled(dev_data))
-		return ret;
+		return -EINVAL;
+
+	return 0;
+}
+
+static int iommu_sva_set_dev_pasid(struct iommu_domain *domain,
+				   struct device *dev, ioasid_t pasid,
+				   struct iommu_domain *old)
+{
+	struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
+	struct protection_domain *sva_pdom = to_pdomain(domain);
+	struct pdom_dev_data *pdom_dev_data;
+	unsigned long flags;
+	int ret;
 
 	/* Add PASID to protection domain pasid list */
 	pdom_dev_data = kzalloc(sizeof(*pdom_dev_data), GFP_KERNEL);
 	if (pdom_dev_data == NULL)
-		return ret;
+		return -ENOMEM;
 
 	pdom_dev_data->pasid = pasid;
 	pdom_dev_data->dev_data = dev_data;
@@ -175,6 +183,7 @@ static void iommu_sva_domain_free(struct iommu_domain *domain)
 }
 
 static const struct iommu_domain_ops amd_sva_domain_ops = {
+	.test_dev      = iommu_sva_test_dev,
 	.set_dev_pasid = iommu_sva_set_dev_pasid,
 	.free	       = iommu_sva_domain_free
 };
-- 
2.43.0