# SPDX-License-Identifier: GPL-2.0-only
config EROFS_FS
tristate "EROFS filesystem support"
depends on BLOCK
help
EROFS (Enhanced Read-Only File System) is a lightweight
read-only file system with modern designs (eg. page-sized
blocks, inline xattrs/data, etc.) for scenarios which need
high-performance read-only requirements, e.g. Android OS
for mobile phones and LIVECDs.
It also provides fixed-sized output compression support,
which improves storage density, keeps relatively higher
compression ratios, which is more useful to achieve high
performance for embedded devices with limited memory.
If unsure, say N.
config EROFS_FS_DEBUG
bool "EROFS debugging feature"
depends on EROFS_FS
help
Print debugging messages and enable more BUG_ONs which check
filesystem consistency and find potential issues aggressively,
which can be used for Android eng build, for example.
For daily use, say N.
config EROFS_FAULT_INJECTION
bool "EROFS fault injection facility"
depends on EROFS_FS
help
Test EROFS to inject faults such as ENOMEM, EIO, and so on.
If unsure, say N.
config EROFS_FS_XATTR
bool "EROFS extended attributes"
depends on EROFS_FS
default y
help
Extended attributes are name:value pairs associated with inodes by
the kernel or by users (see the attr(5) manual page, or visit
for details).
If unsure, say N.
config EROFS_FS_POSIX_ACL
bool "EROFS Access Control Lists"
depends on EROFS_FS_XATTR
select FS_POSIX_ACL
default y
help
Posix Access Control Lists (ACLs) support permissions for users and
groups beyond the owner/group/world scheme.
To learn more about Access Control Lists, visit the POSIX ACLs for
Linux website .
If you don't know what Access Control Lists are, say N.
config EROFS_FS_SECURITY
bool "EROFS Security Labels"
depends on EROFS_FS_XATTR
default y
help
Security labels provide an access control facility to support Linux
Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO
Linux. This option enables an extended attribute handler for file
security labels in the erofs filesystem, so that it requires enabling
the extended attribute support in advance.
If you are not using a security module, say N.
config EROFS_FS_ZIP
bool "EROFS Data Compression Support"
depends on EROFS_FS
select LZ4_DECOMPRESS
default y
help
Enable fixed-sized output compression for EROFS.
If you don't want to enable compression feature, say N.
config EROFS_FS_CLUSTER_PAGE_LIMIT
int "EROFS Cluster Pages Hard Limit"
depends on EROFS_FS_ZIP
range 1 256
default "1"
help
Indicates maximum # of pages of a compressed
physical cluster.
For example, if files in a image were compressed
into 8k-unit, hard limit should not be configured
less than 2. Otherwise, the image will be refused
to mount on this kernel.