On Tue, Dec 12, 2023 at 12:46:20PM -0800, Sagi Shahar wrote:
> From: Erdem Aktas <erdemak...@google.com>
> +/**
> + * Adds a vCPU to a TD (Trusted Domain) with minimum defaults. It will not
> set
> + * up any general purpose registers as they will be initialized by the TDX.
> In
> + * TDX, vCPUs RIP is set to 0xFFFFFFF0. See Intel TDX EAS Section "Initial
> State
> + * of Guest GPRs" for more information on vCPUs initial register values when
> + * entering the TD first time.
> + *
> + * Input Args:
> + * vm - Virtual Machine
> + * vcpuid - The id of the VCPU to add to the VM.
> + */
> +struct kvm_vcpu *td_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id, void
> *guest_code)
> +{
> + struct kvm_vcpu *vcpu;
> +
> + /*
> + * TD setup will not use the value of rip set in vm_vcpu_add anyway, so
> + * NULL can be used for guest_code.
> + */
> + vcpu = vm_vcpu_add(vm, vcpu_id, NULL);
Rather than to call vm_vcpu_add(), is is better to call __vm_vcpu_add(),
__vm_vaddr_alloc() for vcpu->initial_stack_addr and vcpu_mp_state_set() only?
> + tdx_td_vcpu_init(vcpu);
> +
> + load_td_boot_parameters(addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA),
> + vcpu, guest_code);
> +
> + return vcpu;
> +}
> +
...
> +static void td_setup_boot_code(struct kvm_vm *vm, enum
> vm_mem_backing_src_type src_type)
> +{
> + vm_vaddr_t addr;
> + size_t boot_code_allocation = round_up(TD_BOOT_CODE_SIZE, PAGE_SIZE);
> + vm_paddr_t boot_code_base_gpa = FOUR_GIGABYTES_GPA -
> boot_code_allocation;
> + size_t npages = DIV_ROUND_UP(boot_code_allocation, PAGE_SIZE);
> +
> + vm_userspace_mem_region_add(vm, src_type, boot_code_base_gpa, 1, npages,
> + KVM_MEM_PRIVATE);
> + addr = vm_vaddr_alloc_1to1(vm, boot_code_allocation,
> boot_code_base_gpa, 1);
> + TEST_ASSERT_EQ(addr, boot_code_base_gpa);
> +
> + load_td_boot_code(vm);
> +}
> +
> +static size_t td_boot_parameters_size(void)
> +{
> + int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
> + size_t total_per_vcpu_parameters_size =
> + max_vcpus * sizeof(struct td_per_vcpu_parameters);
> +
> + return sizeof(struct td_boot_parameters) +
> total_per_vcpu_parameters_size;
> +}
> +
> +static void td_setup_boot_parameters(struct kvm_vm *vm, enum
> vm_mem_backing_src_type src_type)
> +{
> + vm_vaddr_t addr;
> + size_t boot_params_size = td_boot_parameters_size();
> + int npages = DIV_ROUND_UP(boot_params_size, PAGE_SIZE);
> + size_t total_size = npages * PAGE_SIZE;
> +
> + vm_userspace_mem_region_add(vm, src_type, TD_BOOT_PARAMETERS_GPA, 2,
> + npages, KVM_MEM_PRIVATE);
> + addr = vm_vaddr_alloc_1to1(vm, total_size, TD_BOOT_PARAMETERS_GPA, 2);
> + TEST_ASSERT_EQ(addr, TD_BOOT_PARAMETERS_GPA);
> +}
> +
> +void td_initialize(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type,
> + uint64_t attributes)
> +{
> + uint64_t nr_pages_required;
> +
> + tdx_enable_capabilities(vm);
> +
> + tdx_configure_memory_encryption(vm);
> +
> + tdx_td_init(vm, attributes);
> +
> + nr_pages_required = vm_nr_pages_required(VM_MODE_DEFAULT, 1, 0);
> +
> + /*
> + * Add memory (add 0th memslot) for TD. This will be used to setup the
> + * CPU (provide stack space for the CPU) and to load the elf file.
> + */
> + vm_userspace_mem_region_add(vm, src_type, 0, 0, nr_pages_required,
> + KVM_MEM_PRIVATE);
> +
> + kvm_vm_elf_load(vm, program_invocation_name);
> +
> + vm_init_descriptor_tables(vm);
> +
> + td_setup_boot_code(vm, src_type);
> + td_setup_boot_parameters(vm, src_type);
> +}
Could we define slot ID macros for slot 0, 1, 2?
e.g. BOOT_SLOT_ID_0, BOOT_SLOT_ID_1,BOOT_SLOT_ID_2.
