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(__s390_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	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