1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * syscall_wrapper.h - s390 specific wrappers to syscall definitions
4  *
5  */
6 
7 #ifndef _ASM_S390_SYSCALL_WRAPPER_H
8 #define _ASM_S390_SYSCALL_WRAPPER_H
9 
10 #ifdef CONFIG_COMPAT
11 #define __SC_COMPAT_TYPE(t, a) \
12 	__typeof(__builtin_choose_expr(sizeof(t) > 4, 0L, (t)0)) a
13 
14 #define __SC_COMPAT_CAST(t, a)						\
15 ({									\
16 	long __ReS = a;							\
17 									\
18 	BUILD_BUG_ON((sizeof(t) > 4) && !__TYPE_IS_L(t) &&		\
19 		     !__TYPE_IS_UL(t) && !__TYPE_IS_PTR(t) &&		\
20 		     !__TYPE_IS_LL(t));					\
21 	if (__TYPE_IS_L(t))						\
22 		__ReS = (s32)a;						\
23 	if (__TYPE_IS_UL(t))						\
24 		__ReS = (u32)a;						\
25 	if (__TYPE_IS_PTR(t))						\
26 		__ReS = a & 0x7fffffff;					\
27 	if (__TYPE_IS_LL(t))						\
28 		return -ENOSYS;						\
29 	(t)__ReS;							\
30 })
31 
32 #define __S390_SYS_STUBx(x, name, ...)					\
33 	asmlinkage long __s390_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))\
34 	ALLOW_ERROR_INJECTION(__s390_sys##name, ERRNO);			\
35 	asmlinkage long __s390_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))\
36 	{								\
37 		long ret = __s390x_sys##name(__MAP(x,__SC_COMPAT_CAST,__VA_ARGS__));\
38 		__MAP(x,__SC_TEST,__VA_ARGS__);				\
39 		return ret;						\
40 	}
41 
42 /*
43  * To keep the naming coherent, re-define SYSCALL_DEFINE0 to create an alias
44  * named __s390x_sys_*()
45  */
46 #define COMPAT_SYSCALL_DEFINE0(sname)					\
47 	SYSCALL_METADATA(_##sname, 0);					\
48 	asmlinkage long __s390_compat_sys_##sname(void);		\
49 	ALLOW_ERROR_INJECTION(__s390_compat__sys_##sname, ERRNO);	\
50 	asmlinkage long __s390_compat_sys_##sname(void)
51 
52 #define SYSCALL_DEFINE0(sname)						\
53 	SYSCALL_METADATA(_##sname, 0);					\
54 	asmlinkage long __s390x_sys_##sname(void);			\
55 	ALLOW_ERROR_INJECTION(__s390x_sys_##sname, ERRNO);		\
56 	asmlinkage long __s390_sys_##sname(void)			\
57 		__attribute__((alias(__stringify(__s390x_sys_##sname)))); \
58 	asmlinkage long __s390x_sys_##sname(void)
59 
60 #define COND_SYSCALL(name)						\
61 	cond_syscall(__s390x_sys_##name);				\
62 	cond_syscall(__s390_sys_##name)
63 
64 #define SYS_NI(name)							\
65 	SYSCALL_ALIAS(__s390x_sys_##name, sys_ni_posix_timers);		\
66 	SYSCALL_ALIAS(__s390_sys_##name, sys_ni_posix_timers)
67 
68 #define COMPAT_SYSCALL_DEFINEx(x, name, ...)					\
69 	__diag_push();								\
70 	__diag_ignore(GCC, 8, "-Wattribute-alias",				\
71 		      "Type aliasing is used to sanitize syscall arguments");\
72 	asmlinkage long __s390_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
73 	asmlinkage long __s390_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))	\
74 		__attribute__((alias(__stringify(__se_compat_sys##name))));	\
75 	ALLOW_ERROR_INJECTION(compat_sys##name, ERRNO);				\
76 	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
77 	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));	\
78 	asmlinkage long __se_compat_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\
79 	{									\
80 		long ret = __do_compat_sys##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));\
81 		__MAP(x,__SC_TEST,__VA_ARGS__);					\
82 		return ret;							\
83 	}									\
84 	__diag_pop();								\
85 	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
86 
87 /*
88  * As some compat syscalls may not be implemented, we need to expand
89  * COND_SYSCALL_COMPAT in kernel/sys_ni.c and COMPAT_SYS_NI in
90  * kernel/time/posix-stubs.c to cover this case as well.
91  */
92 #define COND_SYSCALL_COMPAT(name)					\
93 	cond_syscall(__s390_compat_sys_##name)
94 
95 #define COMPAT_SYS_NI(name)						\
96 	SYSCALL_ALIAS(__s390_compat_sys_##name, sys_ni_posix_timers)
97 
98 #else /* CONFIG_COMPAT */
99 
100 #define __S390_SYS_STUBx(x, fullname, name, ...)
101 
102 #define SYSCALL_DEFINE0(sname)						\
103 	SYSCALL_METADATA(_##sname, 0);					\
104 	asmlinkage long __s390x_sys_##sname(void);			\
105 	ALLOW_ERROR_INJECTION(__s390x_sys_##sname, ERRNO);		\
106 	asmlinkage long __s390x_sys_##sname(void)
107 
108 #define COND_SYSCALL(name)						\
109 	cond_syscall(__s390x_sys_##name)
110 
111 #define SYS_NI(name)							\
112 	SYSCALL_ALIAS(__s390x_sys_##name, sys_ni_posix_timers);
113 
114 #endif /* CONFIG_COMPAT */
115 
116 #define __SYSCALL_DEFINEx(x, name, ...)						\
117 	__diag_push();								\
118 	__diag_ignore(GCC, 8, "-Wattribute-alias",				\
119 		      "Type aliasing is used to sanitize syscall arguments");\
120 	asmlinkage long __s390x_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))	\
121 		__attribute__((alias(__stringify(__se_sys##name))));		\
122 	ALLOW_ERROR_INJECTION(__s390x_sys##name, ERRNO);				\
123 	static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));		\
124 	static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
125 	__S390_SYS_STUBx(x, name, __VA_ARGS__)					\
126 	asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))		\
127 	{									\
128 		long ret = __do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));	\
129 		__MAP(x,__SC_TEST,__VA_ARGS__);					\
130 		return ret;							\
131 	}									\
132 	__diag_pop();								\
133 	static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
134 
135 #endif /* _ASM_X86_SYSCALL_WRAPPER_H */
136