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-rw-r--r--arch/x86_64/kernel/Makefile1
-rw-r--r--arch/x86_64/kernel/crash_dump.c47
2 files changed, 48 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile
index fe4cbd1c4b2f..12bc54005e2f 100644
--- a/arch/x86_64/kernel/Makefile
+++ b/arch/x86_64/kernel/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_X86_LOCAL_APIC) += apic.o nmi.o
22obj-$(CONFIG_X86_IO_APIC) += io_apic.o mpparse.o \ 22obj-$(CONFIG_X86_IO_APIC) += io_apic.o mpparse.o \
23 genapic.o genapic_cluster.o genapic_flat.o 23 genapic.o genapic_cluster.o genapic_flat.o
24obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o 24obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o
25obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
25obj-$(CONFIG_PM) += suspend.o 26obj-$(CONFIG_PM) += suspend.o
26obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend_asm.o 27obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend_asm.o
27obj-$(CONFIG_CPU_FREQ) += cpufreq/ 28obj-$(CONFIG_CPU_FREQ) += cpufreq/
diff --git a/arch/x86_64/kernel/crash_dump.c b/arch/x86_64/kernel/crash_dump.c
new file mode 100644
index 000000000000..942deac4d43a
--- /dev/null
+++ b/arch/x86_64/kernel/crash_dump.c
@@ -0,0 +1,47 @@
1/*
2 * kernel/crash_dump.c - Memory preserving reboot related code.
3 *
4 * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
5 * Copyright (C) IBM Corporation, 2004. All rights reserved
6 */
7
8#include <linux/errno.h>
9#include <linux/crash_dump.h>
10
11#include <asm/uaccess.h>
12#include <asm/io.h>
13
14/**
15 * copy_oldmem_page - copy one page from "oldmem"
16 * @pfn: page frame number to be copied
17 * @buf: target memory address for the copy; this can be in kernel address
18 * space or user address space (see @userbuf)
19 * @csize: number of bytes to copy
20 * @offset: offset in bytes into the page (based on pfn) to begin the copy
21 * @userbuf: if set, @buf is in user address space, use copy_to_user(),
22 * otherwise @buf is in kernel address space, use memcpy().
23 *
24 * Copy a page from "oldmem". For this page, there is no pte mapped
25 * in the current kernel. We stitch up a pte, similar to kmap_atomic.
26 */
27ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
28 size_t csize, unsigned long offset, int userbuf)
29{
30 void *vaddr;
31
32 if (!csize)
33 return 0;
34
35 vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
36
37 if (userbuf) {
38 if (copy_to_user(buf, (vaddr + offset), csize)) {
39 iounmap(vaddr);
40 return -EFAULT;
41 }
42 } else
43 memcpy(buf, (vaddr + offset), csize);
44
45 iounmap(vaddr);
46 return csize;
47}