1 files changed, 31 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/lib/riscv/ucall.c b/tools/testing/selftests/kvm/lib/riscv/ucall.c
new file mode 100644
index 000000000000..14ee17151a59
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/riscv/ucall.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ucall support. A ucall is a "hypercall to userspace".
+ *
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ */
+
+#include <linux/kvm.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+
+void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+
+	if (run->exit_reason == KVM_EXIT_RISCV_SBI &&
+	    run->riscv_sbi.extension_id == KVM_RISCV_SELFTESTS_SBI_EXT) {
+		switch (run->riscv_sbi.function_id) {
+		case KVM_RISCV_SELFTESTS_SBI_UCALL:
+			return (void *)run->riscv_sbi.args[0];
+		case KVM_RISCV_SELFTESTS_SBI_UNEXP:
+			vcpu_dump(stderr, vcpu, 2);
+			TEST_ASSERT(0, "Unexpected trap taken by guest");
+			break;
+		default:
+			break;
+		}
+	}
+	return NULL;
+}