1/*
2 * Copyright (C) 2008-2009 Red Hat, Inc.  All rights reserved.
3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 *
5 *   This program is free software; you can redistribute it and/or
6 *   modify it under the terms of the GNU General Public License
7 *   as published by the Free Software Foundation, version 2.
8 *
9 *   This program is distributed in the hope that it will be useful, but
10 *   WITHOUT ANY WARRANTY; without even the implied warranty of
11 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12 *   NON INFRINGEMENT.  See the GNU General Public License for
13 *   more details.
14 *
15 * See asm-generic/syscall.h for descriptions of what we must do here.
16 */
17
18#ifndef _ASM_TILE_SYSCALL_H
19#define _ASM_TILE_SYSCALL_H
20
21#include <linux/sched.h>
22#include <linux/err.h>
23#include <linux/audit.h>
24#include <linux/compat.h>
25#include <arch/abi.h>
26
27/* The array of function pointers for syscalls. */
28extern void *sys_call_table[];
29#ifdef CONFIG_COMPAT
30extern void *compat_sys_call_table[];
31#endif
32
33/*
34 * Only the low 32 bits of orig_r0 are meaningful, so we return int.
35 * This importantly ignores the high bits on 64-bit, so comparisons
36 * sign-extend the low 32 bits.
37 */
38static inline int syscall_get_nr(struct task_struct *t, struct pt_regs *regs)
39{
40	return regs->regs[TREG_SYSCALL_NR];
41}
42
43static inline void syscall_rollback(struct task_struct *task,
44				    struct pt_regs *regs)
45{
46	regs->regs[0] = regs->orig_r0;
47}
48
49static inline long syscall_get_error(struct task_struct *task,
50				     struct pt_regs *regs)
51{
52	unsigned long error = regs->regs[0];
53	return IS_ERR_VALUE(error) ? error : 0;
54}
55
56static inline long syscall_get_return_value(struct task_struct *task,
57					    struct pt_regs *regs)
58{
59	return regs->regs[0];
60}
61
62static inline void syscall_set_return_value(struct task_struct *task,
63					    struct pt_regs *regs,
64					    int error, long val)
65{
66	if (error) {
67		/* R0 is the passed-in negative error, R1 is positive. */
68		regs->regs[0] = error;
69		regs->regs[1] = -error;
70	} else {
71		/* R1 set to zero to indicate no error. */
72		regs->regs[0] = val;
73		regs->regs[1] = 0;
74	}
75}
76
77static inline void syscall_get_arguments(struct task_struct *task,
78					 struct pt_regs *regs,
79					 unsigned int i, unsigned int n,
80					 unsigned long *args)
81{
82	BUG_ON(i + n > 6);
83	memcpy(args, &regs[i], n * sizeof(args[0]));
84}
85
86static inline void syscall_set_arguments(struct task_struct *task,
87					 struct pt_regs *regs,
88					 unsigned int i, unsigned int n,
89					 const unsigned long *args)
90{
91	BUG_ON(i + n > 6);
92	memcpy(&regs[i], args, n * sizeof(args[0]));
93}
94
95/*
96 * We don't care about endianness (__AUDIT_ARCH_LE bit) here because
97 * tile has the same system calls both on little- and big- endian.
98 */
99static inline int syscall_get_arch(void)
100{
101	if (is_compat_task())
102		return AUDIT_ARCH_TILEGX32;
103
104#ifdef CONFIG_TILEGX
105	return AUDIT_ARCH_TILEGX;
106#else
107	return AUDIT_ARCH_TILEPRO;
108#endif
109}
110
111#endif	/* _ASM_TILE_SYSCALL_H */
112