Re: [PATCH v6 07/10] iommufd: Add a nested HW pagetable object

On Tue, Oct 24, 2023 at 08:06:06AM -0700, Yi Liu wrote:

+static struct iommufd_hwpt_nested * +iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx,

• 	  struct iommufd_hwpt_paging *parent,
  

• 	  struct iommufd_device *idev, u32 flags,
  

• 	  const struct iommu_user_data *user_data)
  

+{

• const struct iommu_ops *ops = dev_iommu_ops(idev->dev);
• struct iommufd_hwpt_nested *hwpt_nested;
• struct iommufd_hw_pagetable *hwpt;
• int rc;
• if (flags != 0)

• return ERR_PTR(-EOPNOTSUPP);
  

• if (!user_data)

• return ERR_PTR(-EINVAL);
  

user_data is never NULL now, I removed this

• if (user_data->type == IOMMU_HWPT_DATA_NONE)

• return ERR_PTR(-EINVAL);
  

• if (parent->auto_domain)

• return ERR_PTR(-EINVAL);
  

• if (!parent->nest_parent)

• return ERR_PTR(-EINVAL);
  

And put these all together

if (flags || user_data->type == IOMMU_HWPT_DATA_NONE || !ops->domain_alloc_user) return ERR_PTR(-EOPNOTSUPP); if (parent->auto_domain || !parent->nest_parent) return ERR_PTR(-EINVAL);

• if (!ops->domain_alloc_user)

• return ERR_PTR(-EOPNOTSUPP);
  

• hwpt_nested = __iommufd_object_alloc(ictx, hwpt_nested,

• 			     IOMMUFD_OBJ_HWPT_NESTED,
  

• 			     common.obj);
  

• if (IS_ERR(hwpt_nested))

• return ERR_CAST(hwpt_nested);
  

• hwpt = &hwpt_nested->common;
• refcount_inc(&parent->common.obj.users);
• hwpt_nested->parent = parent;
• hwpt->domain = ops->domain_alloc_user(idev->dev, 0,

And we may as well pass flags here even though we know it is 0 today.

Jason