KVM: selftests: x86: Use TAP interface in the userspace_msr_exit test

Use the kselftest_harness.h interface in this test to get TAP
output, so that it is easier for the user to see what the test
is doing.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20240208204844.119326-9-thuth@redhat.comSigned-off-by: Sean Christopherson <seanjc@google.com>

tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c

@@ -8,6 +8,7 @@
 #define _GNU_SOURCE /* for program_invocation_short_name */
 #include <sys/ioctl.h>
 
+#include "kvm_test_harness.h"
 #include "test_util.h"
 #include "kvm_util.h"
 #include "vmx.h"
@@ -527,14 +528,13 @@ static void run_guest_then_process_ucall_done(struct kvm_vcpu *vcpu)
 	process_ucall_done(vcpu);
 }
 
-static void test_msr_filter_allow(void)
+KVM_ONE_VCPU_TEST_SUITE(user_msr);
+
+KVM_ONE_VCPU_TEST(user_msr, msr_filter_allow, guest_code_filter_allow)
 {
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
+	struct kvm_vm *vm = vcpu->vm;
 	int rc;
 
-	vm = vm_create_with_one_vcpu(&vcpu, guest_code_filter_allow);
-
 	rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
 	TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
 	vm_enable_cap(vm, KVM_CAP_X86_USER_SPACE_MSR, KVM_MSR_EXIT_REASON_FILTER);
@@ -585,8 +585,6 @@ static void test_msr_filter_allow(void)
 	} else {
 		printf("To run the instruction emulated tests set the module parameter 'kvm.force_emulation_prefix=1'\n");
 	}
-
-	kvm_vm_free(vm);
 }
 
 static int handle_ucall(struct kvm_vcpu *vcpu)
@@ -646,16 +644,12 @@ static void handle_wrmsr(struct kvm_run *run)
 	}
 }
 
-static void test_msr_filter_deny(void)
+KVM_ONE_VCPU_TEST(user_msr, msr_filter_deny, guest_code_filter_deny)
 {
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
-	struct kvm_run *run;
+	struct kvm_vm *vm = vcpu->vm;
+	struct kvm_run *run = vcpu->run;
 	int rc;
 
-	vm = vm_create_with_one_vcpu(&vcpu, guest_code_filter_deny);
-	run = vcpu->run;
-
 	rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
 	TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
 	vm_enable_cap(vm, KVM_CAP_X86_USER_SPACE_MSR, KVM_MSR_EXIT_REASON_INVAL |
@@ -689,18 +683,13 @@ static void test_msr_filter_deny(void)
 done:
 	TEST_ASSERT(msr_reads == 4, "Handled 4 rdmsr in user space");
 	TEST_ASSERT(msr_writes == 3, "Handled 3 wrmsr in user space");
-
-	kvm_vm_free(vm);
 }
 
-static void test_msr_permission_bitmap(void)
+KVM_ONE_VCPU_TEST(user_msr, msr_permission_bitmap, guest_code_permission_bitmap)
 {
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
+	struct kvm_vm *vm = vcpu->vm;
 	int rc;
 
-	vm = vm_create_with_one_vcpu(&vcpu, guest_code_permission_bitmap);
-
 	rc = kvm_check_cap(KVM_CAP_X86_USER_SPACE_MSR);
 	TEST_ASSERT(rc, "KVM_CAP_X86_USER_SPACE_MSR is available");
 	vm_enable_cap(vm, KVM_CAP_X86_USER_SPACE_MSR, KVM_MSR_EXIT_REASON_FILTER);
@@ -715,8 +704,6 @@ static void test_msr_permission_bitmap(void)
 	vm_ioctl(vm, KVM_X86_SET_MSR_FILTER, &filter_gs);
 	run_guest_then_process_rdmsr(vcpu, MSR_GS_BASE);
 	run_guest_then_process_ucall_done(vcpu);
-
-	kvm_vm_free(vm);
 }
 
 #define test_user_exit_msr_ioctl(vm, cmd, arg, flag, valid_mask)	\
@@ -786,31 +773,18 @@ static void run_msr_filter_flag_test(struct kvm_vm *vm)
 }
 
 /* Test that attempts to write to the unused bits in a flag fails. */
-static void test_user_exit_msr_flags(void)
+KVM_ONE_VCPU_TEST(user_msr, user_exit_msr_flags, NULL)
 {
-	struct kvm_vcpu *vcpu;
-	struct kvm_vm *vm;
-
-	vm = vm_create_with_one_vcpu(&vcpu, NULL);
+	struct kvm_vm *vm = vcpu->vm;
 
 	/* Test flags for KVM_CAP_X86_USER_SPACE_MSR. */
 	run_user_space_msr_flag_test(vm);
 
 	/* Test flags and range flags for KVM_X86_SET_MSR_FILTER. */
 	run_msr_filter_flag_test(vm);
-
-	kvm_vm_free(vm);
 }
 
 int main(int argc, char *argv[])
 {
-	test_msr_filter_allow();
-
-	test_msr_filter_deny();
-
-	test_msr_permission_bitmap();
-
-	test_user_exit_msr_flags();
-
-	return 0;
+	return test_harness_run(argc, argv);
 }