[PATCH] inode-diet: Move i_pipe into a union

Move the i_pipe pointer into a union that will be shared with i_bdev and
i_cdev.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/fs.h

@@ -528,9 +528,10 @@ struct inode {
 #ifdef CONFIG_QUOTA
 	struct dquot		*i_dquot[MAXQUOTAS];
 #endif
-	/* These three should probably be a union */
 	struct list_head	i_devices;
-	struct pipe_inode_info	*i_pipe;
+	union {
+		struct pipe_inode_info	*i_pipe;
+	};
 	struct block_device	*i_bdev;
 	struct cdev		*i_cdev;
 	int			i_cindex;