fs: move i_readcount

On a 64-bit system, a hole exists in the 'inode' structure after
i_writecount.  This patch moves i_readcount to fill this hole.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>

include/linux/fs.h

@@ -586,6 +586,9 @@ struct inode {
 	atomic_t		i_count;
 	atomic_t		i_dio_count;
 	atomic_t		i_writecount;
+#ifdef CONFIG_IMA
+	atomic_t		i_readcount; /* struct files open RO */
+#endif
 	const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
 	struct file_lock	*i_flock;
 	struct address_space	i_data;
@@ -606,9 +609,6 @@ struct inode {
 	struct hlist_head	i_fsnotify_marks;
 #endif
 
-#ifdef CONFIG_IMA
-	atomic_t		i_readcount; /* struct files open RO */
-#endif
 	void			*i_private; /* fs or device private pointer */
 };