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-rw-r--r--arch/arm/kernel/crash_dump.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/arm/kernel/crash_dump.c b/arch/arm/kernel/crash_dump.c
new file mode 100644
index 000000000..5d1286d51
--- /dev/null
+++ b/arch/arm/kernel/crash_dump.c
@@ -0,0 +1,57 @@
+/*
+ * 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_to_phys(pfn), 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;
+}