diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 01796c4..78af348 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -132,6 +132,7 @@
 struct disk_attribute {
 	struct attribute attr;
 	ssize_t (*show)(struct gendisk *, char *);
+	ssize_t (*store)(struct gendisk *, const char *, size_t);
 };
 
 /*