Index: uspace/srv/fs/minixfs/mfs_utils.c
===================================================================
--- uspace/srv/fs/minixfs/mfs_utils.c	(revision bb0db56421280d74550874133fcc108b90472bde)
+++ uspace/srv/fs/minixfs/mfs_utils.c	(revision b00a2f2f4e2298dfcb737f443d8206afa66ece64)
@@ -31,4 +31,5 @@
  */
 
+#include <byteorder.h>
 #include "mfs_utils.h"
 
@@ -38,5 +39,5 @@
 		return n;
 
-	return (n << 8) | (n >> 8);
+	return uint16_t_byteorder_swap(n);
 }
 
@@ -46,5 +47,13 @@
 		return n;
 
-	return conv16(native, n << 16) | conv16(native, n >> 16);
+	return uint32_t_byteorder_swap(n);
+}
+
+uint64_t conv64(bool native, uint64_t n)
+{
+	if (native)
+		return n;
+
+	return uint64_t_byteorder_swap(n);
 }
 
Index: uspace/srv/fs/minixfs/mfs_utils.h
===================================================================
--- uspace/srv/fs/minixfs/mfs_utils.h	(revision bb0db56421280d74550874133fcc108b90472bde)
+++ uspace/srv/fs/minixfs/mfs_utils.h	(revision b00a2f2f4e2298dfcb737f443d8206afa66ece64)
@@ -39,4 +39,5 @@
 uint16_t conv16(bool native, uint16_t n);
 uint32_t conv32(bool native, uint32_t n);
+uint64_t conv64(bool native, uint64_t n);
 
 #endif