iommu: Set iommu_attach_handle->domain in core

The IOMMU core sets the iommu_attach_handle->domain for the
iommu_attach_group_handle() path, while the iommu_replace_group_handle()
sets it on the caller side. Make the two paths aligned on it.

Link: https://patch.msgid.link/r/20240908114256.979518-3-yi.l.liu@intel.comSigned-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/iommu/iommu.c

@@ -3578,6 +3578,7 @@ int iommu_replace_group_handle(struct iommu_group *group,
 		ret = xa_reserve(&group->pasid_array, IOMMU_NO_PASID, GFP_KERNEL);
 		if (ret)
 			goto err_unlock;
+		handle->domain = new_domain;
 	}
 
 	ret = __iommu_group_set_domain(group, new_domain);

drivers/iommu/iommufd/fault.c

@@ -161,7 +161,6 @@ static int __fault_domain_replace_dev(struct iommufd_device *idev,
 		if (!handle)
 			return -ENOMEM;
 
-		handle->handle.domain = hwpt->domain;
 		handle->idev = idev;
 		ret = iommu_replace_group_handle(idev->igroup->group,
 						 hwpt->domain, &handle->handle);