On Fri, Jul 28, 2023 at 09:37:21AM +0000, Tian, Kevin wrote:
From: Yi Liu yi.l.liu@intel.com Sent: Monday, July 24, 2023 7:04 PM
- @domain_alloc_user: allocate a user iommu domain corresponding to
the input
@hwpt_type that is defined as enum iommu_hwpt_type in the
include/uapi/linux/iommufd.h. A returning domain will be
set to an IOMMU_DOMAIN_NESTED type, upon valid@user_data
and @parent that is a kernel-managed domain. Otherwise,
it will be set to an IOMMU_DOMAIN_UNMANAGED type.Return
ERR_PTR on allocation failure."If @user_data is valid and @parent points to a kernel-managed domain, the returning domain is set to IOMMU_DOMAIN_NESTED type. Otherwise it is set to IOMMU_DOMAIN_UNMANAGED type."
"If @user_data is valid and @parent points to a kernel-managed domain, then the returned domain must be the IOMMU_DOMAIN_NESTED type. Otherwise the returned domain is IOMMU_DOMAIN_UNMANAGED."
Notice the detail that this API expects the driver to set the type and fully initialize the domain, including the generic iommu_domain struct, which is different than alloc_domain.
When we implement this in drivers we should tidy this so all the alloc flows fully initialize the domain internally.
Jason