In preparation for SNP, declutter the vm type check by introducing a
SEV-SNP VM type check as well a transitive set of helper functions.

The SNP VM type is the subset of SEV-ES. Similarly, the SEV-ES and SNP
types are subset of the SEV VM type check.

Signed-off-by: Pratik R. Sampat <pratikrajesh.sampat@amd.com>
---
 .../testing/selftests/kvm/include/x86_64/sev.h  |  4 ++++
 .../selftests/kvm/lib/x86_64/processor.c        |  4 ++--
 tools/testing/selftests/kvm/lib/x86_64/sev.c    | 17 +++++++++++++++++
 .../selftests/kvm/x86_64/sev_smoke_test.c       |  2 +-
 4 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
index e7df5d0987f6..faed91435963 100644
--- a/tools/testing/selftests/kvm/include/x86_64/sev.h
+++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
@@ -29,6 +29,10 @@ enum sev_guest_state {
 
 #define VMGEXIT()		{ __asm__ __volatile__("rep; vmmcall"); }
 
+bool is_sev_vm(struct kvm_vm *vm);
+bool is_sev_es_vm(struct kvm_vm *vm);
+bool is_sev_snp_vm(struct kvm_vm *vm);
+
 void sev_vm_launch(struct kvm_vm *vm, uint32_t policy);
 void sev_vm_launch_measure(struct kvm_vm *vm, uint8_t *measurement);
 void sev_vm_launch_finish(struct kvm_vm *vm);
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 636b29ba8985..13f060748fc2 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -641,7 +641,7 @@ void kvm_arch_vm_post_create(struct kvm_vm *vm)
 	sync_global_to_guest(vm, host_cpu_is_amd);
 	sync_global_to_guest(vm, is_forced_emulation_enabled);
 
-	if (vm->type == KVM_X86_SEV_VM || vm->type == KVM_X86_SEV_ES_VM) {
+	if (is_sev_vm(vm)) {
 		struct kvm_sev_init init = { 0 };
 
 		vm_sev_ioctl(vm, KVM_SEV_INIT2, &init);
@@ -1158,7 +1158,7 @@ void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)
 
 void kvm_init_vm_address_properties(struct kvm_vm *vm)
 {
-	if (vm->type == KVM_X86_SEV_VM || vm->type == KVM_X86_SEV_ES_VM) {
+	if (is_sev_vm(vm)) {
 		vm->arch.sev_fd = open_sev_dev_path_or_exit();
 		vm->arch.c_bit = BIT_ULL(this_cpu_property(X86_PROPERTY_SEV_C_BIT));
 		vm->gpa_tag_mask = vm->arch.c_bit;
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
index e9535ee20b7f..d6e7a422b69d 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/sev.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
@@ -4,6 +4,23 @@
 
 #include "sev.h"
 
+bool is_sev_snp_vm(struct kvm_vm *vm)
+{
+	return vm->type == KVM_X86_SNP_VM;
+}
+
+/* A SNP VM is also a SEV-ES VM */
+bool is_sev_es_vm(struct kvm_vm *vm)
+{
+	return is_sev_snp_vm(vm) || vm->type == KVM_X86_SEV_ES_VM;
+}
+
+/* A SEV-ES and SNP VM is also a SEV VM */
+bool is_sev_vm(struct kvm_vm *vm)
+{
+	return is_sev_snp_vm(vm) || is_sev_es_vm(vm) || vm->type == KVM_X86_SEV_VM;
+}
+
 /*
  * sparsebit_next_clear() can return 0 if [x, 2**64-1] are all set, and the
  * -1 would then cause an underflow back to 2**64 - 1. This is expected and
diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
index 97d9989c8011..53bc0af62bad 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
@@ -123,7 +123,7 @@ static void test_sev(void *guest_code, uint64_t policy)
 	for (;;) {
 		vcpu_run(vcpu);
 
-		if (policy & SEV_POLICY_ES) {
+		if (is_sev_es_vm(vm)) {
 			TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
 				    "Wanted SYSTEM_EVENT, got %s",
 				    exit_reason_str(vcpu->run->exit_reason));
-- 
2.43.0