1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5 #ifndef __ASM_SYSCALL_H
6 #define __ASM_SYSCALL_H
7
8 #include <uapi/linux/audit.h>
9 #include <linux/compat.h>
10 #include <linux/err.h>
11
12 typedef long (*syscall_fn_t)(const struct pt_regs *regs);
13
14 extern const syscall_fn_t sys_call_table[];
15
16 #ifdef CONFIG_COMPAT
17 extern const syscall_fn_t compat_sys_call_table[];
18 #endif
19
syscall_get_nr(struct task_struct * task,struct pt_regs * regs)20 static inline int syscall_get_nr(struct task_struct *task,
21 struct pt_regs *regs)
22 {
23 return regs->syscallno;
24 }
25
syscall_rollback(struct task_struct * task,struct pt_regs * regs)26 static inline void syscall_rollback(struct task_struct *task,
27 struct pt_regs *regs)
28 {
29 regs->regs[0] = regs->orig_x0;
30 }
31
32
syscall_get_error(struct task_struct * task,struct pt_regs * regs)33 static inline long syscall_get_error(struct task_struct *task,
34 struct pt_regs *regs)
35 {
36 unsigned long error = regs->regs[0];
37 return IS_ERR_VALUE(error) ? error : 0;
38 }
39
syscall_get_return_value(struct task_struct * task,struct pt_regs * regs)40 static inline long syscall_get_return_value(struct task_struct *task,
41 struct pt_regs *regs)
42 {
43 return regs->regs[0];
44 }
45
syscall_set_return_value(struct task_struct * task,struct pt_regs * regs,int error,long val)46 static inline void syscall_set_return_value(struct task_struct *task,
47 struct pt_regs *regs,
48 int error, long val)
49 {
50 regs->regs[0] = (long) error ? error : val;
51 }
52
53 #define SYSCALL_MAX_ARGS 6
54
syscall_get_arguments(struct task_struct * task,struct pt_regs * regs,unsigned long * args)55 static inline void syscall_get_arguments(struct task_struct *task,
56 struct pt_regs *regs,
57 unsigned long *args)
58 {
59 args[0] = regs->orig_x0;
60 args++;
61
62 memcpy(args, ®s->regs[1], 5 * sizeof(args[0]));
63 }
64
syscall_set_arguments(struct task_struct * task,struct pt_regs * regs,const unsigned long * args)65 static inline void syscall_set_arguments(struct task_struct *task,
66 struct pt_regs *regs,
67 const unsigned long *args)
68 {
69 regs->orig_x0 = args[0];
70 args++;
71
72 memcpy(®s->regs[1], args, 5 * sizeof(args[0]));
73 }
74
75 /*
76 * We don't care about endianness (__AUDIT_ARCH_LE bit) here because
77 * AArch64 has the same system calls both on little- and big- endian.
78 */
syscall_get_arch(struct task_struct * task)79 static inline int syscall_get_arch(struct task_struct *task)
80 {
81 if (is_compat_thread(task_thread_info(task)))
82 return AUDIT_ARCH_ARM;
83
84 return AUDIT_ARCH_AARCH64;
85 }
86
87 #endif /* __ASM_SYSCALL_H */
88