1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
4 * Copyright 2010 Tilera Corporation. All Rights Reserved.
5 * Copyright 2015 Regents of the University of California, Berkeley
6 *
7 * See asm-generic/syscall.h for descriptions of what we must do here.
8 */
9
10 #ifndef _ASM_RISCV_SYSCALL_H
11 #define _ASM_RISCV_SYSCALL_H
12
13 #include <asm/hwprobe.h>
14 #include <uapi/linux/audit.h>
15 #include <linux/sched.h>
16 #include <linux/err.h>
17
18 /* The array of function pointers for syscalls. */
19 extern void * const sys_call_table[];
20 extern void * const compat_sys_call_table[];
21
22 /*
23 * Only the low 32 bits of orig_r0 are meaningful, so we return int.
24 * This importantly ignores the high bits on 64-bit, so comparisons
25 * sign-extend the low 32 bits.
26 */
syscall_get_nr(struct task_struct * task,struct pt_regs * regs)27 static inline int syscall_get_nr(struct task_struct *task,
28 struct pt_regs *regs)
29 {
30 return regs->a7;
31 }
32
syscall_set_nr(struct task_struct * task,struct pt_regs * regs,int nr)33 static inline void syscall_set_nr(struct task_struct *task,
34 struct pt_regs *regs,
35 int nr)
36 {
37 regs->a7 = nr;
38 }
39
syscall_rollback(struct task_struct * task,struct pt_regs * regs)40 static inline void syscall_rollback(struct task_struct *task,
41 struct pt_regs *regs)
42 {
43 regs->a0 = regs->orig_a0;
44 }
45
syscall_get_error(struct task_struct * task,struct pt_regs * regs)46 static inline long syscall_get_error(struct task_struct *task,
47 struct pt_regs *regs)
48 {
49 unsigned long error = regs->a0;
50
51 return IS_ERR_VALUE(error) ? error : 0;
52 }
53
syscall_get_return_value(struct task_struct * task,struct pt_regs * regs)54 static inline long syscall_get_return_value(struct task_struct *task,
55 struct pt_regs *regs)
56 {
57 return regs->a0;
58 }
59
syscall_set_return_value(struct task_struct * task,struct pt_regs * regs,int error,long val)60 static inline void syscall_set_return_value(struct task_struct *task,
61 struct pt_regs *regs,
62 int error, long val)
63 {
64 regs->a0 = (long) error ?: val;
65 }
66
syscall_get_arguments(struct task_struct * task,struct pt_regs * regs,unsigned long * args)67 static inline void syscall_get_arguments(struct task_struct *task,
68 struct pt_regs *regs,
69 unsigned long *args)
70 {
71 args[0] = regs->orig_a0;
72 args[1] = regs->a1;
73 args[2] = regs->a2;
74 args[3] = regs->a3;
75 args[4] = regs->a4;
76 args[5] = regs->a5;
77 }
78
syscall_set_arguments(struct task_struct * task,struct pt_regs * regs,const unsigned long * args)79 static inline void syscall_set_arguments(struct task_struct *task,
80 struct pt_regs *regs,
81 const unsigned long *args)
82 {
83 regs->orig_a0 = args[0];
84 regs->a1 = args[1];
85 regs->a2 = args[2];
86 regs->a3 = args[3];
87 regs->a4 = args[4];
88 regs->a5 = args[5];
89 }
90
syscall_get_arch(struct task_struct * task)91 static inline int syscall_get_arch(struct task_struct *task)
92 {
93 #ifdef CONFIG_64BIT
94 return AUDIT_ARCH_RISCV64;
95 #else
96 return AUDIT_ARCH_RISCV32;
97 #endif
98 }
99
100 typedef long (*syscall_t)(const struct pt_regs *);
syscall_handler(struct pt_regs * regs,ulong syscall)101 static inline void syscall_handler(struct pt_regs *regs, ulong syscall)
102 {
103 syscall_t fn;
104
105 #ifdef CONFIG_COMPAT
106 if ((regs->status & SR_UXL) == SR_UXL_32)
107 fn = compat_sys_call_table[syscall];
108 else
109 #endif
110 fn = sys_call_table[syscall];
111
112 regs->a0 = fn(regs);
113 }
114
arch_syscall_is_vdso_sigreturn(struct pt_regs * regs)115 static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
116 {
117 return false;
118 }
119
120 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
121
122 asmlinkage long sys_riscv_hwprobe(struct riscv_hwprobe *, size_t, size_t,
123 unsigned long *, unsigned int);
124 #endif /* _ASM_RISCV_SYSCALL_H */
125