1 files changed, 12 insertions, 0 deletions
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 2433cc030c87..e9b3e7880fc0 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -263,6 +263,18 @@ static inline bool ovl_open_flags_need_copy_up(int flags)
 	return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC));
 }
 
+static inline bool ovl_allow_offline_changes(struct ovl_fs *ofs)
+{
+	/*
+	 * To avoid regressions in existing setups with overlay lower offline
+	 * changes, we allow lower changes only if none of the new features
+	 * are used.
+	 */
+	return (!ofs->config.index && !ofs->config.metacopy &&
+		!ofs->config.redirect_dir && ofs->config.xino != OVL_XINO_ON);
+}
+
+
 /* util.c */
 int ovl_want_write(struct dentry *dentry);
 void ovl_drop_write(struct dentry *dentry);