| # SPDX-License-Identifier: GPL-2.0-only | |
| config EROFS_FS | |
| tristate "EROFS filesystem support" | |
| depends on BLOCK | |
| select FS_IOMAP | |
| select LIBCRC32C | |
| help | |
| EROFS (Enhanced Read-Only File System) is a lightweight read-only | |
| file system with modern designs (e.g. no buffer heads, inline | |
| xattrs/data, chunk-based deduplication, multiple devices, etc.) for | |
| scenarios which need high-performance read-only solutions, e.g. | |
| smartphones with Android OS, LiveCDs and high-density hosts with | |
| numerous containers; | |
| It also provides fixed-sized output compression support in order to | |
| improve storage density as well as keep relatively higher compression | |
| ratios and implements in-place decompression to reuse the file page | |
| for compressed data temporarily with proper strategies, which is | |
| quite useful to ensure guaranteed end-to-end runtime decompression | |
| performance under extremely memory pressure without extra cost. | |
| See the documentation at <file:Documentation/filesystems/erofs.rst> | |
| for more details. | |
| 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_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 | |
| <http://acl.bestbits.at/> 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 <http://acl.bestbits.at/>. | |
| 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_ZIP_LZMA | |
| bool "EROFS LZMA compressed data support" | |
| depends on EROFS_FS_ZIP | |
| select XZ_DEC | |
| select XZ_DEC_MICROLZMA | |
| help | |
| Saying Y here includes support for reading EROFS file systems | |
| containing LZMA compressed data, specifically called microLZMA. it | |
| gives better compression ratios than the LZ4 algorithm, at the | |
| expense of more CPU overhead. | |
| LZMA support is an experimental feature for now and so most file | |
| systems will be readable without selecting this option. | |
| If unsure, say N. | |
| config EROFS_FS_ONDEMAND | |
| bool "EROFS fscache-based on-demand read support" | |
| depends on CACHEFILES_ONDEMAND && (EROFS_FS=m && FSCACHE || EROFS_FS=y && FSCACHE=y) | |
| default n | |
| help | |
| This permits EROFS to use fscache-backed data blobs with on-demand | |
| read support. | |
| If unsure, say N. |