linux_dsm_epyc7002/arch/nios2/include/asm/syscall.h
Ley Foon Tan 1000197d80 nios2: System calls handling
This patch adds support for system calls from userspaces. It uses the
asm-generic/unistd.h definitions with architecture spcific syscall.
The sys_call_table is just an array defined in a C file and it contains
pointers to the syscall functions.

Signed-off-by: Ley Foon Tan <lftan@altera.com>
2014-12-08 12:55:58 +08:00

139 lines
2.6 KiB
C

/*
* Copyright Altera Corporation (C) <2014>. All rights reserved
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_NIOS2_SYSCALL_H__
#define __ASM_NIOS2_SYSCALL_H__
#include <linux/err.h>
#include <linux/sched.h>
static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
return regs->r2;
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->r2 = regs->orig_r2;
regs->r7 = regs->orig_r7;
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
return regs->r7 ? regs->r2 : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->r2;
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs, int error, long val)
{
if (error) {
/* error < 0, but nios2 uses > 0 return value */
regs->r2 = -error;
regs->r7 = 1;
} else {
regs->r2 = val;
regs->r7 = 0;
}
}
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);
switch (i) {
case 0:
if (!n--)
break;
*args++ = regs->r4;
case 1:
if (!n--)
break;
*args++ = regs->r5;
case 2:
if (!n--)
break;
*args++ = regs->r6;
case 3:
if (!n--)
break;
*args++ = regs->r7;
case 4:
if (!n--)
break;
*args++ = regs->r8;
case 5:
if (!n--)
break;
*args++ = regs->r9;
case 6:
if (!n--)
break;
default:
BUG();
}
}
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);
switch (i) {
case 0:
if (!n--)
break;
regs->r4 = *args++;
case 1:
if (!n--)
break;
regs->r5 = *args++;
case 2:
if (!n--)
break;
regs->r6 = *args++;
case 3:
if (!n--)
break;
regs->r7 = *args++;
case 4:
if (!n--)
break;
regs->r8 = *args++;
case 5:
if (!n--)
break;
regs->r9 = *args++;
case 6:
if (!n)
break;
default:
BUG();
}
}
#endif