KVM: s390: selftests: Split memop tests

Split success case/copy test from error test, making them independent.
This means they do not share state and are easier to understand.
Also, new test can be added in the same manner without affecting the old
ones. In order to make that simpler, introduce functionality for the
setup of commonly used variables.
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Link: https://lore.kernel.org/r/20220308125841.3271721-2-scgl@linux.ibm.comSigned-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>

tools/testing/selftests/kvm/s390x/memop.c

@@ -18,71 +18,82 @@
 static uint8_t mem1[65536];
 static uint8_t mem2[65536];
 
-static void guest_code(void)
+struct test_default {
+	struct kvm_vm *kvm_vm;
+	struct kvm_run *run;
+	int size;
+};
+
+static struct test_default test_default_init(void *guest_code)
 {
-	int i;
+	struct test_default t;
+
+	t.size = min((size_t)kvm_check_cap(KVM_CAP_S390_MEM_OP), sizeof(mem1));
+	t.kvm_vm = vm_create_default(VCPU_ID, 0, guest_code);
+	t.run = vcpu_state(t.kvm_vm, VCPU_ID);
+	return t;
+}
 
-	for (;;) {
-		for (i = 0; i < sizeof(mem2); i++)
-			mem2[i] = mem1[i];
+static void guest_copy(void)
+{
+	memcpy(&mem2, &mem1, sizeof(mem2));
 	GUEST_SYNC(0);
-	}
 }
 
-int main(int argc, char *argv[])
+static void test_copy(void)
 {
-	struct kvm_vm *vm;
-	struct kvm_run *run;
+	struct test_default t = test_default_init(guest_copy);
 	struct kvm_s390_mem_op ksmo;
-	int rv, i, maxsize;
-
-	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
-
-	maxsize = kvm_check_cap(KVM_CAP_S390_MEM_OP);
-	if (!maxsize) {
-		print_skip("CAP_S390_MEM_OP not supported");
-		exit(KSFT_SKIP);
-	}
-	if (maxsize > sizeof(mem1))
-		maxsize = sizeof(mem1);
-
-	/* Create VM */
-	vm = vm_create_default(VCPU_ID, 0, guest_code);
-	run = vcpu_state(vm, VCPU_ID);
+	int i;
 
 	for (i = 0; i < sizeof(mem1); i++)
 		mem1[i] = i * i + i;
 
 	/* Set the first array */
-	ksmo.gaddr = addr_gva2gpa(vm, (uintptr_t)mem1);
+	ksmo.gaddr = addr_gva2gpa(t.kvm_vm, (uintptr_t)mem1);
 	ksmo.flags = 0;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 
 	/* Let the guest code copy the first array to the second */
-	vcpu_run(vm, VCPU_ID);
-	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
+	vcpu_run(t.kvm_vm, VCPU_ID);
+	TEST_ASSERT(t.run->exit_reason == KVM_EXIT_S390_SIEIC,
 		    "Unexpected exit reason: %u (%s)\n",
-		    run->exit_reason,
-		    exit_reason_str(run->exit_reason));
+		    t.run->exit_reason,
+		    exit_reason_str(t.run->exit_reason));
 
 	memset(mem2, 0xaa, sizeof(mem2));
 
 	/* Get the second array */
 	ksmo.gaddr = (uintptr_t)mem2;
 	ksmo.flags = 0;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_READ;
 	ksmo.buf = (uintptr_t)mem2;
 	ksmo.ar = 0;
-	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 
-	TEST_ASSERT(!memcmp(mem1, mem2, maxsize),
+	TEST_ASSERT(!memcmp(mem1, mem2, t.size),
 		    "Memory contents do not match!");
 
+	kvm_vm_free(t.kvm_vm);
+}
+
+static void guest_idle(void)
+{
+	for (;;)
+		GUEST_SYNC(0);
+}
+
+static void test_errors(void)
+{
+	struct test_default t = test_default_init(guest_idle);
+	struct kvm_s390_mem_op ksmo;
+	int rv;
+
 	/* Check error conditions - first bad size: */
 	ksmo.gaddr = (uintptr_t)mem1;
 	ksmo.flags = 0;
@@ -90,7 +101,7 @@ int main(int argc, char *argv[])
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == E2BIG, "ioctl allows insane sizes");
 
 	/* Zero size: */
@@ -100,65 +111,65 @@ int main(int argc, char *argv[])
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && (errno == EINVAL || errno == ENOMEM),
 		    "ioctl allows 0 as size");
 
 	/* Bad flags: */
 	ksmo.gaddr = (uintptr_t)mem1;
 	ksmo.flags = -1;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows all flags");
 
 	/* Bad operation: */
 	ksmo.gaddr = (uintptr_t)mem1;
 	ksmo.flags = 0;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = -1;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows bad operations");
 
 	/* Bad guest address: */
 	ksmo.gaddr = ~0xfffUL;
 	ksmo.flags = KVM_S390_MEMOP_F_CHECK_ONLY;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv > 0, "ioctl does not report bad guest memory access");
 
 	/* Bad host address: */
 	ksmo.gaddr = (uintptr_t)mem1;
 	ksmo.flags = 0;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = 0;
 	ksmo.ar = 0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EFAULT,
 		    "ioctl does not report bad host memory address");
 
 	/* Bad access register: */
-	run->psw_mask &= ~(3UL << (63 - 17));
-	run->psw_mask |= 1UL << (63 - 17);  /* Enable AR mode */
-	vcpu_run(vm, VCPU_ID);              /* To sync new state to SIE block */
+	t.run->psw_mask &= ~(3UL << (63 - 17));
+	t.run->psw_mask |= 1UL << (63 - 17);  /* Enable AR mode */
+	vcpu_run(t.kvm_vm, VCPU_ID);              /* To sync new state to SIE block */
 	ksmo.gaddr = (uintptr_t)mem1;
 	ksmo.flags = 0;
-	ksmo.size = maxsize;
+	ksmo.size = t.size;
 	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.ar = 17;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows ARs > 15");
-	run->psw_mask &= ~(3UL << (63 - 17));   /* Disable AR mode */
-	vcpu_run(vm, VCPU_ID);                  /* Run to sync new state */
+	t.run->psw_mask &= ~(3UL << (63 - 17));   /* Disable AR mode */
+	vcpu_run(t.kvm_vm, VCPU_ID);                  /* Run to sync new state */
 
 	/* Check that the SIDA calls are rejected for non-protected guests */
 	ksmo.gaddr = 0;
@@ -167,15 +178,31 @@ int main(int argc, char *argv[])
 	ksmo.op = KVM_S390_MEMOP_SIDA_READ;
 	ksmo.buf = (uintptr_t)mem1;
 	ksmo.sida_offset = 0x1c0;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EINVAL,
 		    "ioctl does not reject SIDA_READ in non-protected mode");
 	ksmo.op = KVM_S390_MEMOP_SIDA_WRITE;
-	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	rv = _vcpu_ioctl(t.kvm_vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
 	TEST_ASSERT(rv == -1 && errno == EINVAL,
 		    "ioctl does not reject SIDA_WRITE in non-protected mode");
 
-	kvm_vm_free(vm);
+	kvm_vm_free(t.kvm_vm);
+}
+
+int main(int argc, char *argv[])
+{
+	int memop_cap;
+
+	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
+
+	memop_cap = kvm_check_cap(KVM_CAP_S390_MEM_OP);
+	if (!memop_cap) {
+		print_skip("CAP_S390_MEM_OP not supported");
+		exit(KSFT_SKIP);
+	}
+
+	test_copy();
+	test_errors();
 
 	return 0;
 }