NOTICE: This page has been moved to the kernel documentation tree; current versions can be found here: https://www.kernel.org/doc/html/latest/filesystems/ext4/index.html . Please send documentation updates to the linux-ext4@vger.kernel.org mailing list. This document attempts to describe the on-disk format for ext4 filesystems. The same general ideas should apply to ext2/3 filesystems as well, tho