[PATCH v1 10/20] iommu/apple-dart: 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.

Note the apple_dart_finalize_domain() has another caller than attach_dev
so it has to duplicate the pgsize sanity too.

Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
---
 drivers/iommu/apple-dart.c | 50 +++++++++++++++++++++++++++++---------
 1 file changed, 39 insertions(+), 11 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index b5848770ef482..fb63dcb7462a7 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -593,9 +593,6 @@ static int apple_dart_finalize_domain(struct apple_dart_domain *dart_domain,
 	int ret = 0;
 	int i, j;
 
-	if (dart->pgsize > PAGE_SIZE)
-		return -EINVAL;
-
 	mutex_lock(&dart_domain->init_lock);
 
 	if (dart_domain->finalized)
@@ -643,11 +640,6 @@ apple_dart_mod_streams(struct apple_dart_atomic_stream_map *domain_maps,
 {
 	int i, j;
 
-	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
-		if (domain_maps[i].dart != master_maps[i].dart)
-			return -EINVAL;
-	}
-
 	for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
 		if (!domain_maps[i].dart)
 			break;
@@ -671,6 +663,29 @@ static int apple_dart_domain_add_streams(struct apple_dart_domain *domain,
 				      true);
 }
 
+static int apple_dart_test_dev_paging(struct iommu_domain *domain,
+				      struct device *dev, ioasid_t pasid,
+				      struct iommu_domain *old)
+{
+	struct apple_dart_domain *dart_domain = to_dart_domain(domain);
+	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
+	struct apple_dart *dart = cfg->stream_maps[0].dart;
+
+	if (dart->pgsize > PAGE_SIZE)
+		return -EINVAL;
+	if (dart_domain->finalized) {
+		int i;
+
+		for (i = 0; i < MAX_DARTS_PER_DEVICE; ++i) {
+			if (dart_domain->stream_maps[i].dart !=
+			    cfg->stream_maps[i].dart)
+				return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 static int apple_dart_attach_dev_paging(struct iommu_domain *domain,
 					struct device *dev,
 					struct iommu_domain *old)
@@ -693,6 +708,17 @@ static int apple_dart_attach_dev_paging(struct iommu_domain *domain,
 	return 0;
 }
 
+static int apple_dart_test_dev_identity(struct iommu_domain *domain,
+					struct device *dev, ioasid_t pasid,
+					struct iommu_domain *old)
+{
+	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
+
+	if (!cfg->supports_bypass)
+		return -EINVAL;
+	return 0;
+}
+
 static int apple_dart_attach_dev_identity(struct iommu_domain *domain,
 					  struct device *dev,
 					  struct iommu_domain *old)
@@ -701,15 +727,13 @@ static int apple_dart_attach_dev_identity(struct iommu_domain *domain,
 	struct apple_dart_stream_map *stream_map;
 	int i;
 
-	if (!cfg->supports_bypass)
-		return -EINVAL;
-
 	for_each_stream_map(i, cfg, stream_map)
 		apple_dart_hw_enable_bypass(stream_map);
 	return 0;
 }
 
 static const struct iommu_domain_ops apple_dart_identity_ops = {
+	.test_dev = apple_dart_test_dev_identity,
 	.attach_dev = apple_dart_attach_dev_identity,
 };
 
@@ -776,8 +800,11 @@ static struct iommu_domain *apple_dart_domain_alloc_paging(struct device *dev)
 
 	if (dev) {
 		struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
+		struct apple_dart *dart = cfg->stream_maps[0].dart;
 		int ret;
 
+		if (dart->pgsize > PAGE_SIZE)
+			return ERR_PTR(-EINVAL);
 		ret = apple_dart_finalize_domain(dart_domain, cfg);
 		if (ret) {
 			kfree(dart_domain);
@@ -1010,6 +1037,7 @@ static const struct iommu_ops apple_dart_iommu_ops = {
 	.get_resv_regions = apple_dart_get_resv_regions,
 	.owner = THIS_MODULE,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
+		.test_dev	= apple_dart_test_dev_paging,
 		.attach_dev	= apple_dart_attach_dev_paging,
 		.map_pages	= apple_dart_map_pages,
 		.unmap_pages	= apple_dart_unmap_pages,
-- 
2.43.0