v4.19.13 snapshot.
diff --git a/include/linux/ext2_fs.h b/include/linux/ext2_fs.h
new file mode 100644
index 0000000..1fef885
--- /dev/null
+++ b/include/linux/ext2_fs.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * linux/include/linux/ext2_fs.h
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/include/linux/minix_fs.h
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#ifndef _LINUX_EXT2_FS_H
+#define _LINUX_EXT2_FS_H
+
+#include <linux/types.h>
+#include <linux/magic.h>
+
+#define EXT2_NAME_LEN 255
+
+/*
+ * Maximal count of links to a file
+ */
+#define EXT2_LINK_MAX 32000
+
+#define EXT2_SB_MAGIC_OFFSET 0x38
+#define EXT2_SB_BLOCKS_OFFSET 0x04
+#define EXT2_SB_BSIZE_OFFSET 0x18
+
+static inline u64 ext2_image_size(void *ext2_sb)
+{
+ __u8 *p = ext2_sb;
+ if (*(__le16 *)(p + EXT2_SB_MAGIC_OFFSET) != cpu_to_le16(EXT2_SUPER_MAGIC))
+ return 0;
+ return (u64)le32_to_cpup((__le32 *)(p + EXT2_SB_BLOCKS_OFFSET)) <<
+ le32_to_cpup((__le32 *)(p + EXT2_SB_BSIZE_OFFSET));
+}
+
+#endif /* _LINUX_EXT2_FS_H */