diff --git a/authfs/src/fsverity.rs b/authfs/src/fsverity.rs
index c9070ba..52aacf7 100644
--- a/authfs/src/fsverity.rs
+++ b/authfs/src/fsverity.rs
@@ -19,6 +19,7 @@
 use thiserror::Error;
 
 use crate::auth::Authenticator;
+use crate::common::divide_roundup;
 use crate::crypto::{CryptoError, Sha256Hasher};
 use crate::reader::ReadOnlyDataByChunk;
 
@@ -43,10 +44,6 @@
 
 type HashBuffer = [u8; Sha256Hasher::HASH_SIZE];
 
-fn divide_roundup(dividend: u64, divisor: u64) -> u64 {
-    (dividend + divisor - 1) / divisor
-}
-
 fn hash_with_padding(chunk: &[u8], pad_to: usize) -> Result<HashBuffer, CryptoError> {
     let padding_size = pad_to - chunk.len();
     Sha256Hasher::new()?.update(&chunk)?.update(&ZEROS[..padding_size])?.finalize()
@@ -168,7 +165,6 @@
 }
 
 impl<F: ReadOnlyDataByChunk, M: ReadOnlyDataByChunk> FsverityChunkedFileReader<F, M> {
-    #[allow(dead_code)]
     pub fn new<A: Authenticator>(
         authenticator: &A,
         chunked_file: F,