1 files changed, 64 insertions, 0 deletions
diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c
new file mode 100644
index 000000000..32d710f7e
--- /dev/null
+++ b/arch/x86/kernel/crash_dump_64.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *	Memory preserving reboot related code.
+ *
+ *	Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
+ *	Copyright (C) IBM Corporation, 2004. All rights reserved
+ */
+
+#include <linux/errno.h>
+#include <linux/crash_dump.h>
+#include <linux/uio.h>
+#include <linux/io.h>
+#include <linux/cc_platform.h>
+
+static ssize_t __copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
+				  size_t csize, unsigned long offset,
+				  bool encrypted)
+{
+	void  *vaddr;
+
+	if (!csize)
+		return 0;
+
+	if (encrypted)
+		vaddr = (__force void *)ioremap_encrypted(pfn << PAGE_SHIFT, PAGE_SIZE);
+	else
+		vaddr = (__force void *)ioremap_cache(pfn << PAGE_SHIFT, PAGE_SIZE);
+
+	if (!vaddr)
+		return -ENOMEM;
+
+	csize = copy_to_iter(vaddr + offset, csize, iter);
+
+	iounmap((void __iomem *)vaddr);
+	return csize;
+}
+
+ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
+			 unsigned long offset)
+{
+	return __copy_oldmem_page(iter, pfn, csize, offset, false);
+}
+
+/*
+ * copy_oldmem_page_encrypted - same as copy_oldmem_page() above but ioremap the
+ * memory with the encryption mask set to accommodate kdump on SME-enabled
+ * machines.
+ */
+ssize_t copy_oldmem_page_encrypted(struct iov_iter *iter, unsigned long pfn,
+				   size_t csize, unsigned long offset)
+{
+	return __copy_oldmem_page(iter, pfn, csize, offset, true);
+}
+
+ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
+{
+	struct kvec kvec = { .iov_base = buf, .iov_len = count };
+	struct iov_iter iter;
+
+	iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
+
+	return read_from_oldmem(&iter, count, ppos,
+				cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT));
+}