v4.19.13 snapshot.
diff --git a/include/linux/mpage.h b/include/linux/mpage.h
new file mode 100644
index 0000000..001f1fc
--- /dev/null
+++ b/include/linux/mpage.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * include/linux/mpage.h
+ *
+ * Contains declarations related to preparing and submitting BIOS which contain
+ * multiple pagecache pages.
+ */
+
+/*
+ * (And no, it doesn't do the #ifdef __MPAGE_H thing, and it doesn't do
+ * nested includes. Get it right in the .c file).
+ */
+#ifdef CONFIG_BLOCK
+
+struct writeback_control;
+
+int mpage_readpages(struct address_space *mapping, struct list_head *pages,
+ unsigned nr_pages, get_block_t get_block);
+int mpage_readpage(struct page *page, get_block_t get_block);
+int mpage_writepages(struct address_space *mapping,
+ struct writeback_control *wbc, get_block_t get_block);
+int mpage_writepage(struct page *page, get_block_t *get_block,
+ struct writeback_control *wbc);
+
+#endif