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-rw-r--r--purgatory/arch/i386/crashdump_backup.c51
1 files changed, 51 insertions, 0 deletions
diff --git a/purgatory/arch/i386/crashdump_backup.c b/purgatory/arch/i386/crashdump_backup.c
new file mode 100644
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+++ b/purgatory/arch/i386/crashdump_backup.c
@@ -0,0 +1,51 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Created by: Vivek goyal (vgoyal@in.ibm.com)
+ * Copyright (C) IBM Corporation, 2005. 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 as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+/* Backup region start gets set after /proc/iomem has been parsed. */
+/* We reuse the same code for x86_64 also so changing backup_start to
+ unsigned long */
+unsigned long backup_start = 0;
+
+unsigned long backup_src_start = 0;
+unsigned long backup_src_size = 0;
+
+/* Backup first 640K of memory to backup region as reserved by kexec.
+ * Assuming first 640K has to be present on i386 machines and no address
+ * validity checks have to be performed. */
+
+void crashdump_backup_memory(void)
+{
+ void *dest, *src;
+ size_t size;
+
+ src = (void *) backup_src_start;
+ size = (size_t) backup_src_size;
+
+ if (!size)
+ return;
+
+ if (backup_start) {
+ dest = (void *)(backup_start);
+ memcpy(dest, src, size);
+ }
+}