diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/Makefile | 1 | ||||
-rw-r--r-- | kernel/crash_dump.c | 49 |
2 files changed, 50 insertions, 0 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index cfc8b0dea950..cb05cd05d237 100644 --- a/kernel/Makefile +++ b/kernel/Makefile | |||
@@ -28,6 +28,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o | |||
28 | obj-$(CONFIG_KPROBES) += kprobes.o | 28 | obj-$(CONFIG_KPROBES) += kprobes.o |
29 | obj-$(CONFIG_SYSFS) += ksysfs.o | 29 | obj-$(CONFIG_SYSFS) += ksysfs.o |
30 | obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ | 30 | obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ |
31 | obj-$(CONFIG_CRASH_DUMP) += crash_dump.o | ||
31 | obj-$(CONFIG_SECCOMP) += seccomp.o | 32 | obj-$(CONFIG_SECCOMP) += seccomp.o |
32 | 33 | ||
33 | ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) | 34 | ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) |
diff --git a/kernel/crash_dump.c b/kernel/crash_dump.c new file mode 100644 index 000000000000..5a1e6d5d203e --- /dev/null +++ b/kernel/crash_dump.c | |||
@@ -0,0 +1,49 @@ | |||
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/smp_lock.h> | ||
9 | #include <linux/errno.h> | ||
10 | #include <linux/proc_fs.h> | ||
11 | #include <linux/bootmem.h> | ||
12 | #include <linux/highmem.h> | ||
13 | #include <linux/crash_dump.h> | ||
14 | |||
15 | #include <asm/io.h> | ||
16 | #include <asm/uaccess.h> | ||
17 | |||
18 | /* | ||
19 | * Copy a page from "oldmem". For this page, there is no pte mapped | ||
20 | * in the current kernel. We stitch up a pte, similar to kmap_atomic. | ||
21 | */ | ||
22 | ssize_t copy_oldmem_page(unsigned long pfn, char *buf, | ||
23 | size_t csize, unsigned long offset, int userbuf) | ||
24 | { | ||
25 | void *page, *vaddr; | ||
26 | |||
27 | if (!csize) | ||
28 | return 0; | ||
29 | |||
30 | page = kmalloc(PAGE_SIZE, GFP_KERNEL); | ||
31 | if (!page) | ||
32 | return -ENOMEM; | ||
33 | |||
34 | vaddr = kmap_atomic_pfn(pfn, KM_PTE0); | ||
35 | copy_page(page, vaddr); | ||
36 | kunmap_atomic(vaddr, KM_PTE0); | ||
37 | |||
38 | if (userbuf) { | ||
39 | if (copy_to_user(buf, (page + offset), csize)) { | ||
40 | kfree(page); | ||
41 | return -EFAULT; | ||
42 | } | ||
43 | } else { | ||
44 | memcpy(buf, (page + offset), csize); | ||
45 | } | ||
46 | |||
47 | kfree(page); | ||
48 | return csize; | ||
49 | } | ||