diff options
Diffstat (limited to 'fs/erofs/Kconfig')
| -rw-r--r-- | fs/erofs/Kconfig | 58 |
1 files changed, 38 insertions, 20 deletions
diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig index 74b0aaa7114c..85490370e0ca 100644 --- a/fs/erofs/Kconfig +++ b/fs/erofs/Kconfig @@ -3,18 +3,25 @@ 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 (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. + 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. @@ -76,17 +83,28 @@ config EROFS_FS_ZIP If you don't want to enable compression feature, say N. -config EROFS_FS_CLUSTER_PAGE_LIMIT - int "EROFS Cluster Pages Hard Limit" +config EROFS_FS_ZIP_LZMA + bool "EROFS LZMA compressed data support" depends on EROFS_FS_ZIP - range 1 256 - default "1" + select XZ_DEC + select XZ_DEC_MICROLZMA help - Indicates maximum # of pages of a compressed - physical cluster. + 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. - 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. +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. |