linux/arch/arm/kernel/crash_dump.c
Olaf Hering 93a72052be crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn
The Xen PV drivers in a crashed HVM guest can not connect to the dom0
backend drivers because both frontend and backend drivers are still in
connected state.  To run the connection reset function only in case of a
crashdump, the is_kdump_kernel() function needs to be available for the PV
driver modules.

Consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn into
kernel/crash_dump.c Also export elfcorehdr_addr to make is_kdump_kernel()
usable for modules.

Leave 'elfcorehdr' as early_param().  This changes powerpc from __setup()
to early_param().  It adds an address range check from x86 also on ia64
and powerpc.

[akpm@linux-foundation.org: additional #includes]
[akpm@linux-foundation.org: remove elfcorehdr_addr export]
[akpm@linux-foundation.org: fix for Tejun's mm/nobootmem.c changes]
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:47:19 -07:00

58 lines
1.5 KiB
C

/*
* 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>
/**
* 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;
}