Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 67742c81 authored by Mika Westerberg's avatar Mika Westerberg Committed by Russell King
Browse files

ARM: 6120/1: kdump: implement copy_oldmem_page()



This function is used by vmcore code to read a page from the old
kernel memory.

Signed-off-by: default avatarMika Westerberg <ext-mika.1.westerberg@nokia.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 8594a0c3
Loading
Loading
Loading
Loading
+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ obj-$(CONFIG_ARM_THUMBEE) += thumbee.o
obj-$(CONFIG_KGDB)		+= kgdb.o
obj-$(CONFIG_ARM_UNWIND)	+= unwind.o
obj-$(CONFIG_HAVE_TCM)		+= tcm.o
obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o

obj-$(CONFIG_CRUNCH)		+= crunch.o crunch-bits.o
AFLAGS_crunch-bits.o		:= -Wa,-mcpu=ep9312
+60 −0
Original line number Diff line number Diff line
/*
 * arch/arm/kernel/crash_dump.c
 *
 * Copyright (C) 2010 Nokia Corporation.
 * Author: Mika Westerberg
 *
 * This code is taken from arch/x86/kernel/crash_dump_64.c
 *   Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
 *   Copyright (C) IBM Corporation, 2004. All rights reserved
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/errno.h>
#include <linux/crash_dump.h>
#include <linux/uaccess.h>
#include <linux/io.h>

/* stores the physical address of elf header of crash image */
unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;

/**
 * copy_oldmem_page() - copy one page from old kernel memory
 * @pfn: page frame number to be copied
 * @buf: buffer where the copied page is placed
 * @csize: number of bytes to copy
 * @offset: offset in bytes into the page
 * @userbuf: if set, @buf is int he user address space
 *
 * This function copies one page from old kernel memory into buffer pointed by
 * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes
 * copied or negative error in case of failure.
 */
ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
			 size_t csize, unsigned long offset,
			 int userbuf)
{
	void *vaddr;

	if (!csize)
		return 0;

	vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
	if (!vaddr)
		return -ENOMEM;

	if (userbuf) {
		if (copy_to_user(buf, vaddr + offset, csize)) {
			iounmap(vaddr);
			return -EFAULT;
		}
	} else {
		memcpy(buf, vaddr + offset, csize);
	}

	iounmap(vaddr);
	return csize;
}