aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorVivek Goyal <vgoyal@in.ibm.com>2005-06-25 14:58:19 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-25 16:24:53 -0700
commit60e64d46a58236e3c718074372cab6a5b56a3b15 (patch)
tree194e5fa7a53a1ac4a106b1527ec69cf3c2179bb0 /kernel
parent5f016456c96868c27df248a54d1cc919e7b70a23 (diff)
downloadmrst-s0i3-test-60e64d46a58236e3c718074372cab6a5b56a3b15.tar.gz
mrst-s0i3-test-60e64d46a58236e3c718074372cab6a5b56a3b15.tar.xz
mrst-s0i3-test-60e64d46a58236e3c718074372cab6a5b56a3b15.zip
[PATCH] kdump: Routines for copying dump pages
This patch provides the interfaces necessary to read the dump contents, treating it as a high memory device. Signed off by Hariprasad Nellitheertha <hari@in.ibm.com> Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile1
-rw-r--r--kernel/crash_dump.c49
2 files changed, 50 insertions, 0 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index cfc8b0dea95..cb05cd05d23 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_SYSFS) += ksysfs.o
obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_SECCOMP) += seccomp.o
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 00000000000..5a1e6d5d203
--- /dev/null
+++ b/kernel/crash_dump.c
@@ -0,0 +1,49 @@
+/*
+ * kernel/crash_dump.c - Memory preserving reboot related code.
+ *
+ * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
+ * Copyright (C) IBM Corporation, 2004. All rights reserved
+ */
+
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/proc_fs.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/crash_dump.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+/*
+ * Copy a page from "oldmem". For this page, there is no pte mapped
+ * in the current kernel. We stitch up a pte, similar to kmap_atomic.
+ */
+ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
+ size_t csize, unsigned long offset, int userbuf)
+{
+ void *page, *vaddr;
+
+ if (!csize)
+ return 0;
+
+ page = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ vaddr = kmap_atomic_pfn(pfn, KM_PTE0);
+ copy_page(page, vaddr);
+ kunmap_atomic(vaddr, KM_PTE0);
+
+ if (userbuf) {
+ if (copy_to_user(buf, (page + offset), csize)) {
+ kfree(page);
+ return -EFAULT;
+ }
+ } else {
+ memcpy(buf, (page + offset), csize);
+ }
+
+ kfree(page);
+ return csize;
+}