arch/openrisc/kernel/asm-offsets.c

Source file repositories/reference/linux-study-clean/arch/openrisc/kernel/asm-offsets.c

File Facts

System
Linux kernel
Corpus path
arch/openrisc/kernel/asm-offsets.c
Extension
.c
Size
1956 bytes
Lines
62
Domain
Architecture Layer
Bucket
arch/openrisc
Inferred role
Architecture Layer: implementation source
Status
source 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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * OpenRISC asm-offsets.c
 *
 * Linux architectural port borrowing liberally from similar works of
 * others.  All original copyrights apply as per the original source
 * declaration.
 *
 * Modifications for the OpenRISC architecture:
 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 *
 * This program is used to generate definitions needed by
 * assembly language modules.
 *
 * We use the technique used in the OSF Mach kernel code:
 * generate asm statements containing #defines,
 * compile this file to assembler, and then extract the
 * #defines from the assembly-language output.
 */
#define COMPILE_OFFSETS

#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/thread_info.h>
#include <linux/kbuild.h>
#include <asm/page.h>
#include <asm/processor.h>

int main(void)
{
	/* offsets into the task_struct */
	DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags));
	DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace));
	DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
	DEFINE(TASK_MM, offsetof(struct task_struct, mm));
	DEFINE(TASK_ACTIVE_MM, offsetof(struct task_struct, active_mm));

	/* offsets into thread_info */
	DEFINE(TI_TASK, offsetof(struct thread_info, task));
	DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
	DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
	DEFINE(TI_KSP, offsetof(struct thread_info, ksp));

	DEFINE(PT_SIZE, sizeof(struct pt_regs));

	/* Interrupt register frame */
	DEFINE(STACK_FRAME_OVERHEAD, STACK_FRAME_OVERHEAD);
	DEFINE(INT_FRAME_SIZE, STACK_FRAME_OVERHEAD + sizeof(struct pt_regs));

	DEFINE(NUM_USER_SEGMENTS, TASK_SIZE >> 28);
	return 0;
}

Annotation

Implementation Notes