1 files changed, 62 insertions, 0 deletions
diff --git a/tools/arch/x86/include/asm/orc_types.h b/tools/arch/x86/include/asm/orc_types.h
new file mode 100644
index 000000000..fdbffec4c
--- /dev/null
+++ b/tools/arch/x86/include/asm/orc_types.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
+ */
+
+#ifndef _ORC_TYPES_H
+#define _ORC_TYPES_H
+
+#include <linux/types.h>
+#include <linux/compiler.h>
+
+/*
+ * The ORC_REG_* registers are base registers which are used to find other
+ * registers on the stack.
+ *
+ * ORC_REG_PREV_SP, also known as DWARF Call Frame Address (CFA), is the
+ * address of the previous frame: the caller's SP before it called the current
+ * function.
+ *
+ * ORC_REG_UNDEFINED means the corresponding register's value didn't change in
+ * the current frame.
+ *
+ * The most commonly used base registers are SP and BP -- which the previous SP
+ * is usually based on -- and PREV_SP and UNDEFINED -- which the previous BP is
+ * usually based on.
+ *
+ * The rest of the base registers are needed for special cases like entry code
+ * and GCC realigned stacks.
+ */
+#define ORC_REG_UNDEFINED		0
+#define ORC_REG_PREV_SP			1
+#define ORC_REG_DX			2
+#define ORC_REG_DI			3
+#define ORC_REG_BP			4
+#define ORC_REG_SP			5
+#define ORC_REG_R10			6
+#define ORC_REG_R13			7
+#define ORC_REG_BP_INDIRECT		8
+#define ORC_REG_SP_INDIRECT		9
+#define ORC_REG_MAX			15
+
+#ifndef __ASSEMBLY__
+/*
+ * This struct is more or less a vastly simplified version of the DWARF Call
+ * Frame Information standard.  It contains only the necessary parts of DWARF
+ * CFI, simplified for ease of access by the in-kernel unwinder.  It tells the
+ * unwinder how to find the previous SP and BP (and sometimes entry regs) on
+ * the stack for a given code address.  Each instance of the struct corresponds
+ * to one or more code locations.
+ */
+struct orc_entry {
+	s16		sp_offset;
+	s16		bp_offset;
+	unsigned	sp_reg:4;
+	unsigned	bp_reg:4;
+	unsigned	type:2;
+	unsigned	end:1;
+} __packed;
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ORC_TYPES_H */