Documentation/filesystems/afs.rst

Source file repositories/reference/linux-study-clean/Documentation/filesystems/afs.rst

File Facts

System: Linux kernel
Corpus path: Documentation/filesystems/afs.rst
Extension: .rst
Size: 7971 bytes
Lines: 252
Domain: Support Tooling And Documentation
Bucket: Documentation
Inferred role: Support Tooling And Documentation: documentation
Status: atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.. SPDX-License-Identifier: GPL-2.0

====================
kAFS: AFS FILESYSTEM
====================

.. Contents:

 - Overview.
 - Usage.
 - Mountpoints.
 - Dynamic root.
 - Proc filesystem.
 - The cell database.
 - Security.
 - The @sys substitution.


Overview
========

This filesystem provides a fairly simple secure AFS filesystem driver. It is
under development and does not yet provide the full feature set.  The features
it does support include:

 (*) Security (currently only AFS kaserver and KerberosIV tickets).

 (*) File reading and writing.

 (*) Automounting.

 (*) Local caching (via fscache).

It does not yet support the following AFS features:

 (*) pioctl() system call.


Compilation
===========

The filesystem should be enabled by turning on the kernel configuration
options::

	CONFIG_AF_RXRPC		- The RxRPC protocol transport
	CONFIG_RXKAD		- The RxRPC Kerberos security handler
	CONFIG_AFS_FS		- The AFS filesystem

Additionally, the following can be turned on to aid debugging::

	CONFIG_AF_RXRPC_DEBUG	- Permit AF_RXRPC debugging to be enabled
	CONFIG_AFS_DEBUG	- Permit AFS debugging to be enabled

They permit the debugging messages to be turned on dynamically by manipulating
the masks in the following files::

	/sys/module/af_rxrpc/parameters/debug
	/sys/module/kafs/parameters/debug


Usage
=====

When inserting the driver modules the root cell must be specified along with a
list of volume location server IP addresses::

	modprobe rxrpc
	modprobe kafs rootcell=cambridge.redhat.com:172.16.18.73:172.16.18.91

The first module is the AF_RXRPC network protocol driver.  This provides the

Annotation

Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.