[PATCH 08/17] iommufd: Split iommufd_hw_pagetable_alloc()

Yi Liu
2023-02-09T04:35:07Z

to a helper which accepts the parent hw_pagetable pointer and user_data
pointer. This is a prepareation for supporting userspace hw_pagetable
allocation as caller needs to pass the two parameters to domain_alloc_user
op.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/hw_pagetable.c | 41 ++++++++++++++++++++--------
1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index bda21ec737cf..ee97d2f3cf43 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -22,24 +22,23 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj)
mutex_destroy(&hwpt->devices_lock);
}

-/**
- * iommufd_hw_pagetable_alloc() - Get an iommu_domain for a device
- * @ictx: iommufd context
- * @ioas: IOAS to associate the domain with
- * @dev: Device to get an iommu_domain for
- *
- * Allocate a new iommu_domain and return it as a hw_pagetable.
- */
-struct iommufd_hw_pagetable *
-iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
- struct device *dev)
+static struct iommufd_hw_pagetable *
+__iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx,
+ struct iommufd_ioas *ioas,
+ struct device *dev,
+ struct iommufd_hw_pagetable *parent,
+ void *user_data)
{
const struct iommu_ops *ops;
+ struct iommu_domain *parent_domain = NULL;
struct iommufd_hw_pagetable *hwpt;
int rc;

lockdep_assert_held(&ioas->mutex);

+ if (WARN_ON(!ioas && !parent))
+ return ERR_PTR(-EINVAL);
+
hwpt = iommufd_object_alloc(ictx, hwpt, IOMMUFD_OBJ_HW_PAGETABLE);
if (IS_ERR(hwpt))
return hwpt;
@@ -50,7 +49,10 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
goto out_abort;
}

- hwpt->domain = ops->domain_alloc_user(dev, NULL, NULL);
+ if (parent)
+ parent_domain = parent->domain;
+
+ hwpt->domain = ops->domain_alloc_user(dev, parent_domain, user_data);
if (!hwpt->domain) {
rc = -ENOMEM;
goto out_abort;
@@ -75,3 +77,18 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
iommufd_object_abort(ictx, &hwpt->obj);
return ERR_PTR(rc);
}
+
+/**
+ * iommufd_hw_pagetable_alloc() - Get an iommu_domain for a device
+ * @ictx: iommufd context
+ * @ioas: IOAS to associate the domain with
+ * @dev: Device to get an iommu_domain for
+ *
+ * Allocate a new iommu_domain and return it as a hw_pagetable.
+ */
+struct iommufd_hw_pagetable *
+iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
+ struct device *dev)
+{
+ return __iommufd_hw_pagetable_alloc(ictx, ioas, dev, NULL, NULL);
+}
--
2.34.1