diff options
author | Mika Westerberg <mika.westerberg@iki.fi> | 2010-05-10 09:26:19 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-07-09 15:00:53 +0100 |
commit | 67742c8168ed66fdd6cb5dc90e06c43cdc5bba07 (patch) | |
tree | b9d83a7009ac7d9a7c23ede042ef0301cf2b8d5c /arch/arm/kernel/crash_dump.c | |
parent | 8594a0c333dd79c45c3a24cac8029177728363e0 (diff) | |
download | linux-67742c8168ed66fdd6cb5dc90e06c43cdc5bba07.tar.bz2 |
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: Mika Westerberg <ext-mika.1.westerberg@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/crash_dump.c')
-rw-r--r-- | arch/arm/kernel/crash_dump.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/arm/kernel/crash_dump.c b/arch/arm/kernel/crash_dump.c new file mode 100644 index 000000000000..cd3b853a8a6d --- /dev/null +++ b/arch/arm/kernel/crash_dump.c @@ -0,0 +1,60 @@ +/* + * 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; +} |