summaryrefslogtreecommitdiffstats
path: root/arch/mips/include/asm/syscall.h
blob: c6e9cd2bca8dbf7de5512c9be8de0f2b92db7bd4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * Access to user system call parameters and results
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * See asm-generic/syscall.h for descriptions of what we must do here.
 *
 * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org>
 */

#ifndef __ASM_MIPS_SYSCALL_H
#define __ASM_MIPS_SYSCALL_H

#include <linux/compiler.h>
#include <uapi/linux/audit.h>
#include <linux/elf-em.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <asm/ptrace.h>
#include <asm/unistd.h>

#ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */
#define __NR_syscall 4000
#endif

static inline long syscall_get_nr(struct task_struct *task,
				  struct pt_regs *regs)
{
	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
	if ((config_enabled(CONFIG_32BIT) ||
	    test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
	    (regs->regs[2] == __NR_syscall))
		return regs->regs[4];
	else
		return regs->regs[2];
}

static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
	struct task_struct *task, struct pt_regs *regs, unsigned int n)
{
	unsigned long usp __maybe_unused = regs->regs[29];

	switch (n) {
	case 0: case 1: case 2: case 3:
		*arg = regs->regs[4 + n];

		return 0;

#ifdef CONFIG_32BIT
	case 4: case 5: case 6: case 7:
		return get_user(*arg, (int *)usp + n);
#endif

#ifdef CONFIG_64BIT
	case 4: case 5: case 6: case 7:
#ifdef CONFIG_MIPS32_O32
		if (test_thread_flag(TIF_32BIT_REGS))
			return get_user(*arg, (int *)usp + n);
		else
#endif
			*arg = regs->regs[4 + n];

		return 0;
#endif

	default:
		BUG();
	}

	unreachable();
}

static inline long syscall_get_return_value(struct task_struct *task,
					    struct pt_regs *regs)
{
	return regs->regs[2];
}

static inline void syscall_rollback(struct task_struct *task,
				    struct pt_regs *regs)
{
	/* Do nothing */
}

static inline void syscall_set_return_value(struct task_struct *task,
					    struct pt_regs *regs,
					    int error, long val)
{
	if (error) {
		regs->regs[2] = -error;
		regs->regs[7] = -1;
	} else {
		regs->regs[2] = val;
		regs->regs[7] = 0;
	}
}

static inline void syscall_get_arguments(struct task_struct *task,
					 struct pt_regs *regs,
					 unsigned int i, unsigned int n,
					 unsigned long *args)
{
	int ret;
	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
	if ((config_enabled(CONFIG_32BIT) ||
	    test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
	    (regs->regs[2] == __NR_syscall)) {
		i++;
		n++;
	}

	while (n--)
		ret |= mips_get_syscall_arg(args++, task, regs, i++);

	/*
	 * No way to communicate an error because this is a void function.
	 */
#if 0
	return ret;
#endif
}

extern const unsigned long sys_call_table[];
extern const unsigned long sys32_call_table[];
extern const unsigned long sysn32_call_table[];

static inline int syscall_get_arch(void)
{
	int arch = EM_MIPS;
#ifdef CONFIG_64BIT
	if (!test_thread_flag(TIF_32BIT_REGS))
		arch |= __AUDIT_ARCH_64BIT;
#endif
#if defined(__LITTLE_ENDIAN)
	arch |=  __AUDIT_ARCH_LE;
#endif
	return arch;
}

#endif	/* __ASM_MIPS_SYSCALL_H */
OpenPOWER on IntegriCloud