root/arch/arc/include/asm/syscall.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 */

#ifndef _ASM_ARC_SYSCALL_H
#define _ASM_ARC_SYSCALL_H  1

#include <uapi/linux/audit.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <asm/unistd.h>
#include <asm/ptrace.h>         /* in_syscall() */

extern void *sys_call_table[];

static inline long
syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
        if (user_mode(regs) && in_syscall(regs))
                return regs->r8;
        else
                return -1;
}

static inline void
syscall_set_nr(struct task_struct *task, struct pt_regs *regs, int nr)
{
        /*
         * Unlike syscall_get_nr(), syscall_set_nr() can be called only when
         * the target task is stopped for tracing on entering syscall, so
         * there is no need to have the same check syscall_get_nr() has.
         */
        regs->r8 = nr;
}

static inline void
syscall_rollback(struct task_struct *task, struct pt_regs *regs)
{
        regs->r0 = regs->orig_r0;
}

static inline long
syscall_get_error(struct task_struct *task, struct pt_regs *regs)
{
        /* 0 if syscall succeeded, otherwise -Errorcode */
        return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0;
}

static inline long
syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
{
        return regs->r0;
}

static inline void
syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
                         int error, long val)
{
        regs->r0 = (long) error ?: val;
}

/*
 * @i:      argument index [0,5]
 * @n:      number of arguments; n+i must be [1,6].
 */
static inline void
syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
                      unsigned long *args)
{
        unsigned long *inside_ptregs = &(regs->r0);
        unsigned int n = 6;
        unsigned int i = 0;

        while (n--) {
                args[i++] = (*inside_ptregs);
                inside_ptregs--;
        }
}

static inline void
syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
                      unsigned long *args)
{
        unsigned long *inside_ptregs = &regs->r0;
        unsigned int n = 6;
        unsigned int i = 0;

        while (n--) {
                *inside_ptregs = args[i++];
                inside_ptregs--;
        }
}

static inline int
syscall_get_arch(struct task_struct *task)
{
        return IS_ENABLED(CONFIG_ISA_ARCOMPACT)
                ? (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
                        ? AUDIT_ARCH_ARCOMPACTBE : AUDIT_ARCH_ARCOMPACT)
                : (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
                        ? AUDIT_ARCH_ARCV2BE : AUDIT_ARCH_ARCV2);
}

#endif