1 files changed, 97 insertions, 0 deletions
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index 76c6034428be..b4d936580fbf 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -129,6 +129,103 @@ struct stack_frame {
 	r2;								\
 })
 
+#define CALL_LARGS_0(...)						\
+	long dummy = 0
+#define CALL_LARGS_1(t1, a1)						\
+	long arg1  = (long)(t1)(a1)
+#define CALL_LARGS_2(t1, a1, t2, a2)					\
+	CALL_LARGS_1(t1, a1);						\
+	long arg2 = (long)(t2)(a2)
+#define CALL_LARGS_3(t1, a1, t2, a2, t3, a3)				\
+	CALL_LARGS_2(t1, a1, t2, a2);					\
+	long arg3 = (long)(t3)(a3)
+#define CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4)			\
+	CALL_LARGS_3(t1, a1, t2, a2, t3, a3);				\
+	long arg4  = (long)(t4)(a4)
+#define CALL_LARGS_5(t1, a1, t2, a2, t3, a3, t4, a4, t5, a5)		\
+	CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4);			\
+	long arg5 = (long)(t5)(a5)
+
+#define CALL_REGS_0							\
+	register long r2 asm("2") = dummy
+#define CALL_REGS_1							\
+	register long r2 asm("2") = arg1
+#define CALL_REGS_2							\
+	CALL_REGS_1;							\
+	register long r3 asm("3") = arg2
+#define CALL_REGS_3							\
+	CALL_REGS_2;							\
+	register long r4 asm("4") = arg3
+#define CALL_REGS_4							\
+	CALL_REGS_3;							\
+	register long r5 asm("5") = arg4
+#define CALL_REGS_5							\
+	CALL_REGS_4;							\
+	register long r6 asm("6") = arg5
+
+#define CALL_TYPECHECK_0(...)
+#define CALL_TYPECHECK_1(t, a, ...)					\
+	typecheck(t, a)
+#define CALL_TYPECHECK_2(t, a, ...)					\
+	CALL_TYPECHECK_1(__VA_ARGS__);					\
+	typecheck(t, a)
+#define CALL_TYPECHECK_3(t, a, ...)					\
+	CALL_TYPECHECK_2(__VA_ARGS__);					\
+	typecheck(t, a)
+#define CALL_TYPECHECK_4(t, a, ...)					\
+	CALL_TYPECHECK_3(__VA_ARGS__);					\
+	typecheck(t, a)
+#define CALL_TYPECHECK_5(t, a, ...)					\
+	CALL_TYPECHECK_4(__VA_ARGS__);					\
+	typecheck(t, a)
+
+#define CALL_PARM_0(...) void
+#define CALL_PARM_1(t, a, ...) t
+#define CALL_PARM_2(t, a, ...) t, CALL_PARM_1(__VA_ARGS__)
+#define CALL_PARM_3(t, a, ...) t, CALL_PARM_2(__VA_ARGS__)
+#define CALL_PARM_4(t, a, ...) t, CALL_PARM_3(__VA_ARGS__)
+#define CALL_PARM_5(t, a, ...) t, CALL_PARM_4(__VA_ARGS__)
+#define CALL_PARM_6(t, a, ...) t, CALL_PARM_5(__VA_ARGS__)
+
+/*
+ * Use call_on_stack() to call a function switching to a specified
+ * stack. Proper sign and zero extension of function arguments is
+ * done. Usage:
+ *
+ * rc = call_on_stack(nr, stack, rettype, fn, t1, a1, t2, a2, ...)
+ *
+ * - nr specifies the number of function arguments of fn.
+ * - stack specifies the stack to be used.
+ * - fn is the function to be called.
+ * - rettype is the return type of fn.
+ * - t1, a1, ... are pairs, where t1 must match the type of the first
+ *   argument of fn, t2 the second, etc. a1 is the corresponding
+ *   first function argument (not name), etc.
+ */
+#define call_on_stack(nr, stack, rettype, fn, ...)			\
+({									\
+	rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = fn;		\
+	unsigned long frame = current_frame_address();			\
+	unsigned long __stack = stack;					\
+	unsigned long prev;						\
+	CALL_LARGS_##nr(__VA_ARGS__);					\
+	CALL_REGS_##nr;							\
+									\
+	CALL_TYPECHECK_##nr(__VA_ARGS__);				\
+	asm volatile(							\
+		"	lgr	%[_prev],15\n"				\
+		"	lg	15,%[_stack]\n"				\
+		"	stg	%[_frame],%[_bc](15)\n"			\
+		"	brasl	14,%[_fn]\n"				\
+		"	lgr	15,%[_prev]\n"				\
+		: [_prev] "=&d" (prev), CALL_FMT_##nr			\
+		: [_stack] "R" (__stack),				\
+		  [_bc] "i" (offsetof(struct stack_frame, back_chain)),	\
+		  [_frame] "d" (frame),					\
+		  [_fn] "X" (__fn) : CALL_CLOBBER_##nr);		\
+	(rettype)r2;							\
+})
+
 #define CALL_ON_STACK_NORETURN(fn, stack)				\
 ({									\
 	asm volatile(							\