1/*
2 * Access to user system call parameters and results
3 *
4 * Copyright (C) 2008 Red Hat, Inc.  All rights reserved.
5 *
6 * This copyrighted material is made available to anyone wishing to use,
7 * modify, copy, or redistribute it subject to the terms and conditions
8 * of the GNU General Public License v.2.
9 *
10 * See asm-generic/syscall.h for descriptions of what we must do here.
11 */
12
13#ifndef _ASM_SYSCALL_H
14#define _ASM_SYSCALL_H	1
15
16#include <uapi/linux/audit.h>
17#include <linux/sched.h>
18#include <linux/thread_info.h>
19
20/* ftrace syscalls requires exporting the sys_call_table */
21#ifdef CONFIG_FTRACE_SYSCALLS
22extern const unsigned long sys_call_table[];
23#endif /* CONFIG_FTRACE_SYSCALLS */
24
25static inline long syscall_get_nr(struct task_struct *task,
26				  struct pt_regs *regs)
27{
28	return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L;
29}
30
31static inline void syscall_rollback(struct task_struct *task,
32				    struct pt_regs *regs)
33{
34	regs->gpr[3] = regs->orig_gpr3;
35}
36
37static inline long syscall_get_error(struct task_struct *task,
38				     struct pt_regs *regs)
39{
40	return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0;
41}
42
43static inline long syscall_get_return_value(struct task_struct *task,
44					    struct pt_regs *regs)
45{
46	return regs->gpr[3];
47}
48
49static inline void syscall_set_return_value(struct task_struct *task,
50					    struct pt_regs *regs,
51					    int error, long val)
52{
53	if (error) {
54		regs->ccr |= 0x10000000L;
55		regs->gpr[3] = -error;
56	} else {
57		regs->ccr &= ~0x10000000L;
58		regs->gpr[3] = val;
59	}
60}
61
62static inline void syscall_get_arguments(struct task_struct *task,
63					 struct pt_regs *regs,
64					 unsigned int i, unsigned int n,
65					 unsigned long *args)
66{
67	BUG_ON(i + n > 6);
68#ifdef CONFIG_PPC64
69	if (test_tsk_thread_flag(task, TIF_32BIT)) {
70		/*
71		 * Zero-extend 32-bit argument values.  The high bits are
72		 * garbage ignored by the actual syscall dispatch.
73		 */
74		while (n-- > 0)
75			args[n] = (u32) regs->gpr[3 + i + n];
76		return;
77	}
78#endif
79	memcpy(args, &regs->gpr[3 + i], n * sizeof(args[0]));
80}
81
82static inline void syscall_set_arguments(struct task_struct *task,
83					 struct pt_regs *regs,
84					 unsigned int i, unsigned int n,
85					 const unsigned long *args)
86{
87	BUG_ON(i + n > 6);
88	memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
89}
90
91static inline int syscall_get_arch(void)
92{
93	int arch = is_32bit_task() ? AUDIT_ARCH_PPC : AUDIT_ARCH_PPC64;
94#ifdef __LITTLE_ENDIAN__
95	arch |= __AUDIT_ARCH_LE;
96#endif
97	return arch;
98}
99#endif	/* _ASM_SYSCALL_H */
100