get rid of duplicate logics in __SC_....[1-6] definitions

All those guys have the same form - "take a list of type/name pairs,
apply some macro to each of them".  Abstract that part away, convert
all __SC_FOO##x(__VA_ARGS__) to __MAP(x,__SC_FOO,__VA_ARGS__).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

include/linux/compat.h

@@ -27,12 +27,6 @@
 #define __SC_DELOUSE(t,v) ((t)(unsigned long)(v))
 #endif
 
-#define __SC_CCAST1(t1, a1)      __SC_DELOUSE(t1,a1)
-#define __SC_CCAST2(t2, a2, ...) __SC_DELOUSE(t2,a2), __SC_CCAST1(__VA_ARGS__)
-#define __SC_CCAST3(t3, a3, ...) __SC_DELOUSE(t3,a3), __SC_CCAST2(__VA_ARGS__)
-#define __SC_CCAST4(t4, a4, ...) __SC_DELOUSE(t4,a4), __SC_CCAST3(__VA_ARGS__)
-#define __SC_CCAST5(t5, a5, ...) __SC_DELOUSE(t5,a5), __SC_CCAST4(__VA_ARGS__)
-#define __SC_CCAST6(t6, a6, ...) __SC_DELOUSE(t6,a6), __SC_CCAST5(__VA_ARGS__)
 #define COMPAT_SYSCALL_DEFINE1(name, ...) \
         COMPAT_SYSCALL_DEFINEx(1, _##name, __VA_ARGS__)
 #define COMPAT_SYSCALL_DEFINE2(name, ...) \
@@ -49,19 +43,19 @@
 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
 
 #define COMPAT_SYSCALL_DEFINEx(x, name, ...)				\
-	asmlinkage long compat_sys##name(__SC_DECL##x(__VA_ARGS__));	\
-	static inline long C_SYSC##name(__SC_DECL##x(__VA_ARGS__));	\
-	asmlinkage long compat_SyS##name(__SC_LONG##x(__VA_ARGS__))	\
+	asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
+	static inline long C_SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
+	asmlinkage long compat_SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__))\
 	{								\
-		return (long) C_SYSC##name(__SC_CCAST##x(__VA_ARGS__));	\
+		return C_SYSC##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));	\
 	}								\
 	SYSCALL_ALIAS(compat_sys##name, compat_SyS##name);		\
-	static inline long C_SYSC##name(__SC_DECL##x(__VA_ARGS__))
+	static inline long C_SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
 #else /* CONFIG_HAVE_SYSCALL_WRAPPERS */
 
 #define COMPAT_SYSCALL_DEFINEx(x, name, ...)				\
-	asmlinkage long compat_sys##name(__SC_DECL##x(__VA_ARGS__))
+	asmlinkage long compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
 #endif /* CONFIG_HAVE_SYSCALL_WRAPPERS */
 

include/linux/syscalls.h

@@ -78,49 +78,31 @@ struct sigaltstack;
 #include <linux/key.h>
 #include <trace/syscall.h>
 
-#define __SC_DECL1(t1, a1)	t1 a1
-#define __SC_DECL2(t2, a2, ...) t2 a2, __SC_DECL1(__VA_ARGS__)
-#define __SC_DECL3(t3, a3, ...) t3 a3, __SC_DECL2(__VA_ARGS__)
-#define __SC_DECL4(t4, a4, ...) t4 a4, __SC_DECL3(__VA_ARGS__)
-#define __SC_DECL5(t5, a5, ...) t5 a5, __SC_DECL4(__VA_ARGS__)
-#define __SC_DECL6(t6, a6, ...) t6 a6, __SC_DECL5(__VA_ARGS__)
-
-#define __SC_LONG1(t1, a1) 	long a1
-#define __SC_LONG2(t2, a2, ...) long a2, __SC_LONG1(__VA_ARGS__)
-#define __SC_LONG3(t3, a3, ...) long a3, __SC_LONG2(__VA_ARGS__)
-#define __SC_LONG4(t4, a4, ...) long a4, __SC_LONG3(__VA_ARGS__)
-#define __SC_LONG5(t5, a5, ...) long a5, __SC_LONG4(__VA_ARGS__)
-#define __SC_LONG6(t6, a6, ...) long a6, __SC_LONG5(__VA_ARGS__)
-
-#define __SC_CAST1(t1, a1)	(t1) a1
-#define __SC_CAST2(t2, a2, ...) (t2) a2, __SC_CAST1(__VA_ARGS__)
-#define __SC_CAST3(t3, a3, ...) (t3) a3, __SC_CAST2(__VA_ARGS__)
-#define __SC_CAST4(t4, a4, ...) (t4) a4, __SC_CAST3(__VA_ARGS__)
-#define __SC_CAST5(t5, a5, ...) (t5) a5, __SC_CAST4(__VA_ARGS__)
-#define __SC_CAST6(t6, a6, ...) (t6) a6, __SC_CAST5(__VA_ARGS__)
-
-#define __SC_TEST(type)		BUILD_BUG_ON(sizeof(type) > sizeof(long))
-#define __SC_TEST1(t1, a1)	__SC_TEST(t1)
-#define __SC_TEST2(t2, a2, ...)	__SC_TEST(t2); __SC_TEST1(__VA_ARGS__)
-#define __SC_TEST3(t3, a3, ...)	__SC_TEST(t3); __SC_TEST2(__VA_ARGS__)
-#define __SC_TEST4(t4, a4, ...)	__SC_TEST(t4); __SC_TEST3(__VA_ARGS__)
-#define __SC_TEST5(t5, a5, ...)	__SC_TEST(t5); __SC_TEST4(__VA_ARGS__)
-#define __SC_TEST6(t6, a6, ...)	__SC_TEST(t6); __SC_TEST5(__VA_ARGS__)
+/*
+ * __MAP - apply a macro to syscall arguments
+ * __MAP(n, m, t1, a1, t2, a2, ..., tn, an) will expand to
+ *    m(t1, a1), m(t2, a2), ..., m(tn, an)
+ * The first argument must be equal to the amount of type/name
+ * pairs given.  Note that this list of pairs (i.e. the arguments
+ * of __MAP starting at the third one) is in the same format as
+ * for SYSCALL_DEFINE<n>/COMPAT_SYSCALL_DEFINE<n>
+ */
+#define __MAP1(m,t,a) m(t,a)
+#define __MAP2(m,t,a,...) m(t,a), __MAP1(m,__VA_ARGS__)
+#define __MAP3(m,t,a,...) m(t,a), __MAP2(m,__VA_ARGS__)
+#define __MAP4(m,t,a,...) m(t,a), __MAP3(m,__VA_ARGS__)
+#define __MAP5(m,t,a,...) m(t,a), __MAP4(m,__VA_ARGS__)
+#define __MAP6(m,t,a,...) m(t,a), __MAP5(m,__VA_ARGS__)
+#define __MAP(n,...) __MAP##n(__VA_ARGS__)
+
+#define __SC_DECL(t, a)	t a
+#define __SC_LONG(t, a)	long a
+#define __SC_CAST(t, a)	(t) a
+#define __SC_TEST(t, a) (void)BUILD_BUG_ON_ZERO(sizeof(type) > sizeof(long))
 
 #ifdef CONFIG_FTRACE_SYSCALLS
-#define __SC_STR_ADECL1(t, a)		#a
-#define __SC_STR_ADECL2(t, a, ...)	#a, __SC_STR_ADECL1(__VA_ARGS__)
-#define __SC_STR_ADECL3(t, a, ...)	#a, __SC_STR_ADECL2(__VA_ARGS__)
-#define __SC_STR_ADECL4(t, a, ...)	#a, __SC_STR_ADECL3(__VA_ARGS__)
-#define __SC_STR_ADECL5(t, a, ...)	#a, __SC_STR_ADECL4(__VA_ARGS__)
-#define __SC_STR_ADECL6(t, a, ...)	#a, __SC_STR_ADECL5(__VA_ARGS__)
-
-#define __SC_STR_TDECL1(t, a)		#t
-#define __SC_STR_TDECL2(t, a, ...)	#t, __SC_STR_TDECL1(__VA_ARGS__)
-#define __SC_STR_TDECL3(t, a, ...)	#t, __SC_STR_TDECL2(__VA_ARGS__)
-#define __SC_STR_TDECL4(t, a, ...)	#t, __SC_STR_TDECL3(__VA_ARGS__)
-#define __SC_STR_TDECL5(t, a, ...)	#t, __SC_STR_TDECL4(__VA_ARGS__)
-#define __SC_STR_TDECL6(t, a, ...)	#t, __SC_STR_TDECL5(__VA_ARGS__)
+#define __SC_STR_ADECL(t, a)	#a
+#define __SC_STR_TDECL(t, a)	#t
 
 extern struct ftrace_event_class event_class_syscall_enter;
 extern struct ftrace_event_class event_class_syscall_exit;
@@ -217,10 +199,10 @@ extern struct trace_event_functions exit_syscall_print_funcs;
 #ifdef CONFIG_FTRACE_SYSCALLS
 #define SYSCALL_DEFINEx(x, sname, ...)				\
 	static const char *types_##sname[] = {			\
-		__SC_STR_TDECL##x(__VA_ARGS__)			\
+		__MAP(x,__SC_STR_TDECL,__VA_ARGS__)		\
 	};							\
 	static const char *args_##sname[] = {			\
-		__SC_STR_ADECL##x(__VA_ARGS__)			\
+		__MAP(x,__SC_STR_ADECL,__VA_ARGS__)		\
 	};							\
 	SYSCALL_METADATA(sname, x);				\
 	__SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
@@ -234,21 +216,21 @@ extern struct trace_event_functions exit_syscall_print_funcs;
 #define SYSCALL_DEFINE(name) static inline long SYSC_##name
 
 #define __SYSCALL_DEFINEx(x, name, ...)					\
-	asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__));		\
-	static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__));	\
-	asmlinkage long SyS##name(__SC_LONG##x(__VA_ARGS__))		\
+	asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
+	static inline long SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
+	asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\
 	{								\
-		__SC_TEST##x(__VA_ARGS__);				\
-		return (long) SYSC##name(__SC_CAST##x(__VA_ARGS__));	\
+		__MAP(x,__SC_TEST,__VA_ARGS__);				\
+		return SYSC##name(__MAP(x,__SC_CAST,__VA_ARGS__));	\
 	}								\
 	SYSCALL_ALIAS(sys##name, SyS##name);				\
-	static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__))
+	static inline long SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
 #else /* CONFIG_HAVE_SYSCALL_WRAPPERS */
 
 #define SYSCALL_DEFINE(name) asmlinkage long sys_##name
 #define __SYSCALL_DEFINEx(x, name, ...)					\
-	asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__))
+	asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
 #endif /* CONFIG_HAVE_SYSCALL_WRAPPERS */