arch/arc/include/asm/syscall.h

Source file repositories/reference/linux-study-clean/arch/arc/include/asm/syscall.h

File Facts

System
Linux kernel
Corpus path
arch/arc/include/asm/syscall.h
Extension
.h
Size
2369 bytes
Lines
106
Domain
Architecture Layer
Bucket
arch/arc
Inferred role
Architecture Layer: syscall or user/kernel boundary
Status
core implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#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

Annotation

Implementation Notes