syscall_wrapper.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * syscall_wrapper.h - riscv specific wrappers to syscall definitions
  4 *
  5 * Based on arch/arm64/include/syscall_wrapper.h
  6 */
  7
  8#ifndef __ASM_SYSCALL_WRAPPER_H
  9#define __ASM_SYSCALL_WRAPPER_H
 10
 11#include <asm/ptrace.h>
 12
 13asmlinkage long __riscv_sys_ni_syscall(const struct pt_regs *);
 14
 15#ifdef CONFIG_64BIT
 16
 17#define __SYSCALL_SE_DEFINEx(x, prefix, name, ...)					\
 18	static long __se_##prefix##name(__MAP(x,__SC_LONG,__VA_ARGS__));		\
 19	static long __se_##prefix##name(__MAP(x,__SC_LONG,__VA_ARGS__))
 20
 21#define SC_RISCV_REGS_TO_ARGS(x, ...)							\
 22	__MAP(x,__SC_ARGS								\
 23	      ,,regs->orig_a0,,regs->a1,,regs->a2					\
 24	      ,,regs->a3,,regs->a4,,regs->a5,,regs->a6)
 25
 26#else
 27/*
 28 * Use type aliasing to ensure registers a0-a6 are correctly passed to the syscall
 29 * implementation when >word-size arguments are used.
 30 */
 31#define __SYSCALL_SE_DEFINEx(x, prefix, name, ...)					\
 32	__diag_push();									\
 33	__diag_ignore(GCC, 8, "-Wattribute-alias",					\
 34			"Type aliasing is used to sanitize syscall arguments");		\
 35	static long __se_##prefix##name(ulong, ulong, ulong, ulong, ulong, ulong, 	\
 36					ulong)						\
 37			__attribute__((alias(__stringify(___se_##prefix##name))));	\
 38	__diag_pop();									\
 39	static long noinline ___se_##prefix##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\
 40			__used;								\
 41	static long ___se_##prefix##name(__MAP(x,__SC_LONG,__VA_ARGS__))
 42
 43#define SC_RISCV_REGS_TO_ARGS(x, ...) \
 44	regs->orig_a0,regs->a1,regs->a2,regs->a3,regs->a4,regs->a5,regs->a6
 45
 46#endif /* CONFIG_64BIT */
 47
 48#ifdef CONFIG_COMPAT
 49
 50#define COMPAT_SYSCALL_DEFINEx(x, name, ...)						\
 51	asmlinkage long __riscv_compat_sys##name(const struct pt_regs *regs);		\
 52	ALLOW_ERROR_INJECTION(__riscv_compat_sys##name, ERRNO);				\
 53	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
 54	__SYSCALL_SE_DEFINEx(x, compat_sys, name, __VA_ARGS__)				\
 55	{										\
 56		return __do_compat_sys##name(__MAP(x,__SC_DELOUSE,__VA_ARGS__));	\
 57	}										\
 58	asmlinkage long __riscv_compat_sys##name(const struct pt_regs *regs)		\
 59	{										\
 60		return __se_compat_sys##name(SC_RISCV_REGS_TO_ARGS(x,__VA_ARGS__));	\
 61	}										\
 62	static inline long __do_compat_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 63
 64#define COMPAT_SYSCALL_DEFINE0(sname)							\
 65	asmlinkage long __riscv_compat_sys_##sname(const struct pt_regs *__unused);	\
 66	ALLOW_ERROR_INJECTION(__riscv_compat_sys_##sname, ERRNO);			\
 67	asmlinkage long __riscv_compat_sys_##sname(const struct pt_regs *__unused)
 68
 69#define COND_SYSCALL_COMPAT(name) 							\
 70	asmlinkage long __weak __riscv_compat_sys_##name(const struct pt_regs *regs);	\
 71	asmlinkage long __weak __riscv_compat_sys_##name(const struct pt_regs *regs)	\
 72	{										\
 73		return sys_ni_syscall();						\
 74	}
 75
 76#endif /* CONFIG_COMPAT */
 77
 78#define __SYSCALL_DEFINEx(x, name, ...)						\
 79	asmlinkage long __riscv_sys##name(const struct pt_regs *regs);		\
 80	ALLOW_ERROR_INJECTION(__riscv_sys##name, ERRNO);			\
 81	static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));	\
 82	__SYSCALL_SE_DEFINEx(x, sys, name, __VA_ARGS__)				\
 83	{									\
 84		long ret = __do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));	\
 85		__MAP(x,__SC_TEST,__VA_ARGS__);					\
 86		__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__));		\
 87		return ret;							\
 88	}									\
 89	asmlinkage long __riscv_sys##name(const struct pt_regs *regs)		\
 90	{									\
 91		return __se_sys##name(SC_RISCV_REGS_TO_ARGS(x,__VA_ARGS__));	\
 92	}									\
 93	static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 94
 95#define SYSCALL_DEFINE0(sname)							\
 96	SYSCALL_METADATA(_##sname, 0);						\
 97	asmlinkage long __riscv_sys_##sname(const struct pt_regs *__unused);	\
 98	ALLOW_ERROR_INJECTION(__riscv_sys_##sname, ERRNO);			\
 99	asmlinkage long __riscv_sys_##sname(const struct pt_regs *__unused)
100
101#define COND_SYSCALL(name)							\
102	asmlinkage long __weak __riscv_sys_##name(const struct pt_regs *regs);	\
103	asmlinkage long __weak __riscv_sys_##name(const struct pt_regs *regs)	\
104	{									\
105		return sys_ni_syscall();					\
106	}
107
108#endif /* __ASM_SYSCALL_WRAPPER_H */