/*
* 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 <[email protected]>
*/

#ifndef __ASM_MIPS_SYSCALL_H
#define __ASM_MIPS_SYSCALL_H

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

static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
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 + 4 * 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 + 4 * n);
else
#endif
*arg = regs->regs[4 + n];

return 0;
#endif

default:
BUG();
}
}

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

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)
{
unsigned long arg;
int ret;

while (n--)
ret |= mips_get_syscall_arg(&arg, 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
arch |= __AUDIT_ARCH_64BIT;
#endif
#if defined(__LITTLE_ENDIAN)
arch |= __AUDIT_ARCH_LE;
#endif
return arch;
}

#endif /* __ASM_MIPS_SYSCALL_H */