/*
* Access to user system call parameters and results
*
* Copyright (C) 2008 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License v.2.
*
* See asm-generic/syscall.h for descriptions of what we must do here.
*/

#ifndef _ASM_SYSCALL_H
#define _ASM_SYSCALL_H 1

#include <linux/sched.h>

/* ftrace syscalls requires exporting the sys_call_table */
#ifdef CONFIG_FTRACE_SYSCALLS
extern const unsigned long *sys_call_table;
#endif /* CONFIG_FTRACE_SYSCALLS */

static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L;
}

static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->gpr[3] = regs->orig_gpr3;
}

static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0;
}

static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->gpr[3];
}

static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
if (error) {
regs->ccr |= 0x10000000L;
regs->gpr[3] = -error;
} else {
regs->ccr &= ~0x10000000L;
regs->gpr[3] = val;
}
}

static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
BUG_ON(i + n > 6);
#ifdef CONFIG_PPC64
if (test_tsk_thread_flag(task, TIF_32BIT)) {
/*
* Zero-extend 32-bit argument values. The high bits are
* garbage ignored by the actual syscall dispatch.
*/
while (n-- > 0)
args[n] = (u32) regs->gpr[3 + i + n];
return;
}
#endif
memcpy(args, &regs->gpr[3 + i], n * sizeof(args[0]));
}

static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
BUG_ON(i + n > 6);
memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
}

#endif /* _ASM_SYSCALL_H */