diff --git a/fs/open.c b/fs/open.c
index a6b054e..e27c205 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -403,7 +403,7 @@
 	if (inode->i_op && inode->i_op->fallocate)
 		ret = inode->i_op->fallocate(inode, mode, offset, len);
 	else
-		ret = -ENOSYS;
+		ret = -EOPNOTSUPP;
 
 out_fput:
 	fput(file);