1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4  */
5 
6 #ifndef _ASM_ARC_SYSCALL_H
7 #define _ASM_ARC_SYSCALL_H  1
8 
9 #include <uapi/linux/audit.h>
10 #include <linux/err.h>
11 #include <linux/sched.h>
12 #include <asm/unistd.h>
13 #include <asm/ptrace.h>		/* in_syscall() */
14 
15 extern void *sys_call_table[];
16 
17 static inline long
18 syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
19 {
20 	if (user_mode(regs) && in_syscall(regs))
21 		return regs->r8;
22 	else
23 		return -1;
24 }
25 
26 static inline void
27 syscall_set_nr(struct task_struct *task, struct pt_regs *regs, int nr)
28 {
29 	/*
30 	 * Unlike syscall_get_nr(), syscall_set_nr() can be called only when
31 	 * the target task is stopped for tracing on entering syscall, so
32 	 * there is no need to have the same check syscall_get_nr() has.
33 	 */
34 	regs->r8 = nr;
35 }
36 
37 static inline void
38 syscall_rollback(struct task_struct *task, struct pt_regs *regs)
39 {
40 	regs->r0 = regs->orig_r0;
41 }
42 
43 static inline long
44 syscall_get_error(struct task_struct *task, struct pt_regs *regs)
45 {
46 	/* 0 if syscall succeeded, otherwise -Errorcode */
47 	return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0;
48 }
49 
50 static inline long
51 syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
52 {
53 	return regs->r0;
54 }
55 
56 static inline void
57 syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
58 			 int error, long val)
59 {
60 	regs->r0 = (long) error ?: val;
61 }
62 
63 /*
64  * @i:      argument index [0,5]
65  * @n:      number of arguments; n+i must be [1,6].
66  */
67 static inline void
68 syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
69 		      unsigned long *args)
70 {
71 	unsigned long *inside_ptregs = &(regs->r0);
72 	unsigned int n = 6;
73 	unsigned int i = 0;
74 
75 	while (n--) {
76 		args[i++] = (*inside_ptregs);
77 		inside_ptregs--;
78 	}
79 }
80 
81 static inline void
82 syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
83 		      unsigned long *args)
84 {
85 	unsigned long *inside_ptregs = &regs->r0;
86 	unsigned int n = 6;
87 	unsigned int i = 0;
88 
89 	while (n--) {
90 		*inside_ptregs = args[i++];
91 		inside_ptregs--;
92 	}
93 }
94 
95 static inline int
96 syscall_get_arch(struct task_struct *task)
97 {
98 	return IS_ENABLED(CONFIG_ISA_ARCOMPACT)
99 		? (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
100 			? AUDIT_ARCH_ARCOMPACTBE : AUDIT_ARCH_ARCOMPACT)
101 		: (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
102 			? AUDIT_ARCH_ARCV2BE : AUDIT_ARCH_ARCV2);
103 }
104 
105 #endif
106