iommufd: Add alloc_domain_nested op to iommufd_viommu_ops
Allow IOMMU driver to use a vIOMMU object that holds a nesting parent
hwpt/domain to allocate a nested domain.
Link: https://patch.msgid.link/r/2dcdb5e405dc0deb68230564530d989d285d959c.1730836219.git.nicolinc@nvidia.com
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>