diff --git a/fs/yaffs2/yaffs_guts.h b/fs/yaffs2/yaffs_guts.h
--- a/fs/yaffs2/yaffs_guts.h
+++ b/fs/yaffs2/yaffs_guts.h
@@ -537,7 +537,7 @@ struct yaffs_DeviceStruct
 	int (*initialiseNAND)(struct yaffs_DeviceStruct *dev);
 
 #ifdef CONFIG_YAFFS_YAFFS2
-	int (*writeChunkWithTagsToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, yaffs_ExtendedTags *tags);
+	int (*writeChunkWithTagsToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, const yaffs_ExtendedTags *tags);
 	int (*readChunkWithTagsFromNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, __u8 *data, yaffs_ExtendedTags *tags);
 	int (*markNANDBlockBad)(struct yaffs_DeviceStruct *dev, int blockNo);
 	int (*queryNANDBlock)(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber);