[PATCH RFC 09/10] kvm: selftests: add GUEST_SHARED_* macros for shared ucall implementations

[Michael Roth <michael.roth@amd.com>]

Introduce GUEST_SHARED_* macros, which are mostly analogous to existing
GUEST_SYNC/GUEST_ASSERT/etc macros used to simplify guest code that
uses ucall for host/guest synchronization.

There are also some new CHECK_GUEST_SHARED_* macros intended to provide
similar helpers in the host code that can pair directly with the guest
versions.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../selftests/kvm/include/ucall_common.h      | 68 +++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/ucall_common.h b/tools/testing/selftests/kvm/include/ucall_common.h
index ae0e8eec9734..b9b220dbd6c3 100644
--- a/tools/testing/selftests/kvm/include/ucall_common.h
+++ b/tools/testing/selftests/kvm/include/ucall_common.h
@@ -48,6 +48,7 @@ vm_vaddr_t ucall_shared_alloc(struct kvm_vm *vm, int count);
 void ucall_shared(struct ucall *uc, uint64_t cmd, int nargs, ...);
 uint64_t get_ucall_shared(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc);
 
+/* Helpers for host/guest synchronization using ucall_shared */
 #define GUEST_SYNC_ARGS(stage, arg1, arg2, arg3, arg4)	\
 				ucall(UCALL_SYNC, 6, "hello", stage, arg1, arg2, arg3, arg4)
 #define GUEST_SYNC(stage)	ucall(UCALL_SYNC, 2, "hello", stage)
@@ -76,4 +77,71 @@ uint64_t get_ucall_shared(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc)
 
 #define GUEST_ASSERT_EQ(a, b) __GUEST_ASSERT((a) == (b), #a " == " #b, 2, a, b)
 
+/* Helper macros for ucall synchronization via shared memory/ucall struct. */
+#define GUEST_SHARED_SYNC_ARGS(uc, stage, arg1, arg2, arg3, arg4) \
+	ucall_shared(uc, UCALL_SYNC, 6, "hello", stage, arg1, arg2, arg3, arg4)
+#define GUEST_SHARED_SYNC(uc, stage) \
+	ucall_shared(uc, UCALL_SYNC, 2, "hello", stage)
+#define GUEST_SHARED_DONE(uc) \
+	ucall_shared(uc, UCALL_DONE, 0)
+#define __GUEST_SHARED_ASSERT(uc, _condition, _condstr, _nargs, _args...) do {    \
+	if (!(_condition))                                                        \
+		ucall_shared(uc, UCALL_ABORT, 2 + _nargs,                         \
+			"Failed guest assert: "                                   \
+			_condstr, __LINE__, _args);                               \
+} while (0)
+
+#define GUEST_SHARED_ASSERT(uc, _condition) \
+	__GUEST_SHARED_ASSERT(uc, _condition, #_condition, 0, 0)
+
+#define GUEST_SHARED_ASSERT_1(uc, _condition, arg1) \
+	__GUEST_SHARED_ASSERT(uc, _condition, #_condition, 1, (arg1))
+
+#define GUEST_SHARED_ASSERT_2(uc, _condition, arg1, arg2) \
+	__GUEST_SHARED_ASSERT(uc, _condition, #_condition, 2, (arg1), (arg2))
+
+#define GUEST_SHARED_ASSERT_3(uc, _condition, arg1, arg2, arg3) \
+	__GUEST_SHARED_ASSERT(uc, _condition, #_condition, 3, (arg1), (arg2), (arg3))
+
+#define GUEST_SHARED_ASSERT_4(uc, _condition, arg1, arg2, arg3, arg4) \
+	__GUEST_SHARED_ASSERT(uc, _condition, #_condition, 4, (arg1), (arg2), (arg3), (arg4))
+
+#define GUEST_SHARED_ASSERT_EQ(uc, a, b) \
+	__GUEST_SHARED_ASSERT(uc, (a) == (b), #a " == " #b, 2, a, b)
+
+#define __CHECK_SHARED_STATE(uc, uc_cmd, uc_cmd_expected) do {			\
+	if (uc_cmd != uc_cmd_expected) {					\
+		if (uc_cmd == UCALL_ABORT)					\
+			TEST_FAIL("Unexpected guest abort: \"%s\" at %s:%ld",	\
+				  (const char *)uc->args[0], __FILE__,		\
+				  uc->args[1]);					\
+		else								\
+		    TEST_FAIL("Unexpected ucall command/state: %" PRIu64,	\
+			      uc_cmd);						\
+	}									\
+} while (0)
+
+#define CHECK_SHARED_SYNC(vm, vcpu_id, uc, stage) do {				\
+	uint64_t uc_cmd = get_ucall_shared(vm, vcpu_id, uc);			\
+	TEST_ASSERT(uc_cmd == UCALL_SYNC,					\
+		    "Unexpected ucall command/state: %" PRIu64, uc_cmd);	\
+	TEST_ASSERT(!strcmp((char *)uc->args[0], "hello"),			\
+		    "Invalid ucall signature argument."); 			\
+	TEST_ASSERT(uc->args[1] == stage,					\
+		    "Invalid ucall sync stage: %" PRIu64, uc->args[1]);		\
+} while (0)
+
+#define CHECK_SHARED_DONE(vm, vcpu_id, uc) do {					\
+	uint64_t uc_cmd = get_ucall_shared(vm, vcpu_id, uc);			\
+	__CHECK_SHARED_STATE(uc, uc_cmd, UCALL_DONE);				\
+	TEST_ASSERT(uc_cmd == UCALL_DONE,					\
+		    "Unexpected ucall command/state: %" PRIu64, uc_cmd);	\
+} while (0)
+
+#define CHECK_SHARED_ABORT(vm, vcpu_id, uc) do {				\
+	uint64_t uc_cmd = get_ucall_shared(vm, vcpu_id, uc);			\
+	TEST_ASSERT(uc_cmd == UCALL_ABORT,					\
+		    "Unexpected ucall command/state: %" PRIu64, uc_cmd);	\
+} while (0)
+
 #endif /* SELFTEST_KVM_UCALL_COMMON_H */
-- 
2.25.1