[PATCH v1 16/20] iommu/omap-iommu: Implement omap_iommu_domain_test_dev

Nicolin Chen
2025-10-13T00:07:36Z

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

Following the test_dev guideline, replace dev_err with dev_dbg.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/omap-iommu.c | 41 ++++++++++++++++++++++++--------------
1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 9f0057ccea573..26a7803e4144f 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1392,9 +1392,6 @@ static int omap_iommu_attach_init(struct device *dev,
int i;

odomain->num_iommus = omap_iommu_count(dev);
- if (!odomain->num_iommus)
- return -ENODEV;
-
odomain->iommus = kcalloc(odomain->num_iommus, sizeof(*iommu),
GFP_ATOMIC);
if (!odomain->iommus)
@@ -1431,6 +1428,31 @@ static void omap_iommu_detach_fini(struct omap_iommu_domain *odomain)
odomain->iommus = NULL;
}

+static int omap_iommu_domain_test_dev(struct iommu_domain *domain,
+ struct device *dev, ioasid_t pasid,
+ struct iommu_domain *old)
+{
+ struct omap_iommu_arch_data *arch_data = dev_iommu_priv_get(dev);
+ struct omap_iommu_domain *omap_domain = to_omap_domain(domain);
+
+ if (!arch_data || !arch_data->iommu_dev) {
+ dev_dbg(dev, "device doesn't have an associated iommu\n");
+ return -ENODEV;
+ }
+
+ scoped_guard(spinlock, &omap_domain->lock) {
+ /* only a single client device can be attached to a domain */
+ if (omap_domain->dev) {
+ dev_dbg(dev, "iommu domain is already attached\n");
+ return -EINVAL;
+ }
+ if (!omap_iommu_count(dev))
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
static int omap_iommu_attach_dev(struct iommu_domain *domain,
struct device *dev, struct iommu_domain *old)
{
@@ -1441,20 +1463,8 @@ static int omap_iommu_attach_dev(struct iommu_domain *domain,
int ret = 0;
int i;

- if (!arch_data || !arch_data->iommu_dev) {
- dev_err(dev, "device doesn't have an associated iommu\n");
- return -ENODEV;
- }
-
spin_lock(&omap_domain->lock);

- /* only a single client device can be attached to a domain */
- if (omap_domain->dev) {
- dev_err(dev, "iommu domain is already attached\n");
- ret = -EINVAL;
- goto out;
- }
-
ret = omap_iommu_attach_init(dev, omap_domain);
if (ret) {
dev_err(dev, "failed to allocate required iommu data %d\n",
@@ -1724,6 +1734,7 @@ static const struct iommu_ops omap_iommu_ops = {
.device_group = generic_single_device_group,
.of_xlate = omap_iommu_of_xlate,
.default_domain_ops = &(const struct iommu_domain_ops) {
+ .test_dev = omap_iommu_domain_test_dev,
.attach_dev = omap_iommu_attach_dev,
.map_pages = omap_iommu_map,
.unmap_pages = omap_iommu_unmap,
--
2.43.0