| // This is based on a multi-book template where each chapter uses level 1 |
| // headings. See doc/multi-book.txt as the example from asciidoc documentation. |
| // |
| // We pull in the document info in xml format from docinfo.xml. We do this |
| // because asciidoc is unable to handle multiple entry revision histories, |
| // and we really need an area to set up various docbook sections like copyright |
| // and legal notice sections. |
| // |
| XFS Filesystem Disk Structures |
| ============================== |
| :doctype: book |
| :docinfo1: |
| |
| High Level Design |
| ================= |
| |
| [partintro] |
| -- |
| XFS is a high performance filesystem which was designed to maximize parallel |
| throughput and to scale up to extremely large 64-bit storage systems. |
| Originally developed by SGI in October 1993 for IRIX, XFS can handle large |
| files, large filesystems, many inodes, large directories, large file |
| attributes, and large allocations. Filesystems are optimized for parallel |
| access by splitting the storage device into semi-autonomous allocation groups. |
| XFS employs branching trees (B+ trees) to facilitate fast searches of large |
| lists; it also uses delayed extent-based allocation to improve data contiguity |
| and IO performance. |
| |
| This document describes the on-disk layout of an XFS filesystem and how to use |
| the debugging tools +xfs_db+ and +xfs_logprint+ to inspect the metadata |
| structures. It also describes how on-disk metadata relates to the higher level |
| design goals. |
| |
| The information contained in this document derives from the XFS source code in |
| the Linux kernel as of v4.3. This book's source code is available at |
| +git://git.kernel.org/pub/scm/fs/xfs/xfs-documentation.git+. Feedback should |
| be sent to the XFS mailing list, currently at +xfs@oss.sgi.com+. |
| |
| [NOTE] |
| All fields in XFS metadata structures are in big-endian byte order except for |
| log items which are formatted in host order. |
| -- |
| |
| // Push titles down one level |
| :leveloffset: 1 |
| |
| include::overview.asciidoc[] |
| |
| include::metadata_integrity.asciidoc[] |
| |
| include::reflink.asciidoc[] |
| |
| include::reconstruction.asciidoc[] |
| |
| include::common_types.asciidoc[] |
| |
| include::magic.asciidoc[] |
| |
| include::testing.asciidoc[] |
| |
| // return titles to normal |
| :leveloffset: 0 |
| |
| Global Structures |
| ================= |
| |
| :leveloffset: 1 |
| |
| include::btrees.asciidoc[] |
| |
| include::allocation_groups.asciidoc[] |
| |
| include::rmapbt.asciidoc[] |
| |
| include::refcountbt.asciidoc[] |
| |
| include::journaling_log.asciidoc[] |
| |
| include::internal_inodes.asciidoc[] |
| |
| :leveloffset: 0 |
| |
| Dynamically Allocated Structures |
| ================================ |
| |
| :leveloffset: 1 |
| |
| include::ondisk_inode.asciidoc[] |
| |
| include::data_extents.asciidoc[] |
| |
| include::directories.asciidoc[] |
| |
| include::extended_attributes.asciidoc[] |
| |
| include::symbolic_links.asciidoc[] |
| |
| :leveloffset: 0 |
