fs/erofs/Kconfig | 45 ++++++++++++++++++++++++++++++--------------- 1 file changed, 30 insertions(+), 15 deletions(-)
Refine the description to better highlight its features and use cases.
In addition, add instructions for building it as a module and clarify
the compression option.
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
fs/erofs/Kconfig | 45 ++++++++++++++++++++++++++++++---------------
1 file changed, 30 insertions(+), 15 deletions(-)
diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig
index a9f645f57bb2..9489ed8ad95b 100644
--- a/fs/erofs/Kconfig
+++ b/fs/erofs/Kconfig
@@ -16,22 +16,36 @@ config EROFS_FS
select ZLIB_INFLATE if EROFS_FS_ZIP_DEFLATE
select ZSTD_DECOMPRESS if EROFS_FS_ZIP_ZSTD
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 transparent compression and deduplication support to
- improve storage density and maintain relatively high compression
- ratios, and it implements in-place decompression to temporarily reuse
- page cache for compressed data using proper strategies, which is
- quite useful for ensuring guaranteed end-to-end runtime decompression
+ EROFS (Enhanced Read-Only File System) is a modern, lightweight,
+ secure read-only filesystem for various use cases, such as immutable
+ system images, container images, application sandboxes, and datasets.
+
+ EROFS uses a flexible, hierarchical on-disk design so that features
+ can be enabled on demand: the core on-disk format is block-aligned in
+ order to perform optimally on all kinds of devices, including block
+ and memory-backed devices; the format is easy to parse and has zero
+ metadata redundancy, unlike generic filesystems, making it ideal for
+ for filesytem auditing and remote access; inline data, random-access
+ friendly directory data, inline/shared extended attributes and
+ chunk-based deduplication ensure space efficiency while maintaining
+ high performance.
+
+ Optionally, it supports multiple devices to reference external data,
+ enabling data sharing for container images.
+
+ It also has advanced encoded on-disk layouts, particularly for data
+ compression and fine-grained deduplication. It utilizes fixed-size
+ output compression to improve storage density while keeping relatively
+ high compression ratios. Furthermore, it implements in-place
+ decompression to reuse file pages to keep compressed data temporarily
+ with proper strategies, which ensures guaranteed end-to-end runtime
performance under extreme memory pressure without extra cost.
- See the documentation at <file:Documentation/filesystems/erofs.rst>
- and the web pages at <https://erofs.docs.kernel.org> for more details.
+ For more details, see the web pages at <https://erofs.docs.kernel.org>
+ and the documentation at <file:Documentation/filesystems/erofs.rst>.
+
+ To compile EROFS filesystem support as a module, choose M here. The
+ module will be called erofs.
If unsure, say N.
@@ -105,7 +119,8 @@ config EROFS_FS_ZIP
depends on EROFS_FS
default y
help
- Enable transparent compression support for EROFS file systems.
+ Enable EROFS compression layouts so that filesystems containing
+ compressed files can be parsed by the kernel.
If you don't want to enable compression feature, say N.
--
2.43.5On 3/23/26 17:48, Gao Xiang wrote: > Refine the description to better highlight its features and use cases. > > In addition, add instructions for building it as a module and clarify > the compression option. > > Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> > --- > fs/erofs/Kconfig | 45 ++++++++++++++++++++++++++++++--------------- > 1 file changed, 30 insertions(+), 15 deletions(-) > > diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig > index a9f645f57bb2..9489ed8ad95b 100644 > --- a/fs/erofs/Kconfig > +++ b/fs/erofs/Kconfig > @@ -16,22 +16,36 @@ config EROFS_FS > select ZLIB_INFLATE if EROFS_FS_ZIP_DEFLATE > select ZSTD_DECOMPRESS if EROFS_FS_ZIP_ZSTD > 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 transparent compression and deduplication support to > - improve storage density and maintain relatively high compression > - ratios, and it implements in-place decompression to temporarily reuse > - page cache for compressed data using proper strategies, which is > - quite useful for ensuring guaranteed end-to-end runtime decompression > + EROFS (Enhanced Read-Only File System) is a modern, lightweight, > + secure read-only filesystem for various use cases, such as immutable > + system images, container images, application sandboxes, and datasets. > + > + EROFS uses a flexible, hierarchical on-disk design so that features > + can be enabled on demand: the core on-disk format is block-aligned in > + order to perform optimally on all kinds of devices, including block > + and memory-backed devices; the format is easy to parse and has zero > + metadata redundancy, unlike generic filesystems, making it ideal for > + for filesytem auditing and remote access; inline data, random-access duplicated 'for'? otherwise, looks good to me. Reviewed-by: Chao Yu <chao@kernel.org> Thanks, > + friendly directory data, inline/shared extended attributes and > + chunk-based deduplication ensure space efficiency while maintaining > + high performance. > + > + Optionally, it supports multiple devices to reference external data, > + enabling data sharing for container images. > + > + It also has advanced encoded on-disk layouts, particularly for data > + compression and fine-grained deduplication. It utilizes fixed-size > + output compression to improve storage density while keeping relatively > + high compression ratios. Furthermore, it implements in-place > + decompression to reuse file pages to keep compressed data temporarily > + with proper strategies, which ensures guaranteed end-to-end runtime > performance under extreme memory pressure without extra cost. > > - See the documentation at <file:Documentation/filesystems/erofs.rst> > - and the web pages at <https://erofs.docs.kernel.org> for more details. > + For more details, see the web pages at <https://erofs.docs.kernel.org> > + and the documentation at <file:Documentation/filesystems/erofs.rst>. > + > + To compile EROFS filesystem support as a module, choose M here. The > + module will be called erofs. > > If unsure, say N. > > @@ -105,7 +119,8 @@ config EROFS_FS_ZIP > depends on EROFS_FS > default y > help > - Enable transparent compression support for EROFS file systems. > + Enable EROFS compression layouts so that filesystems containing > + compressed files can be parsed by the kernel. > > If you don't want to enable compression feature, say N. >
Hi Chao, On 2026/3/23 17:59, Chao Yu wrote: > On 3/23/26 17:48, Gao Xiang wrote: >> Refine the description to better highlight its features and use cases. >> >> In addition, add instructions for building it as a module and clarify >> the compression option. >> >> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> >> --- >> fs/erofs/Kconfig | 45 ++++++++++++++++++++++++++++++--------------- >> 1 file changed, 30 insertions(+), 15 deletions(-) >> >> diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig >> index a9f645f57bb2..9489ed8ad95b 100644 >> --- a/fs/erofs/Kconfig >> +++ b/fs/erofs/Kconfig >> @@ -16,22 +16,36 @@ config EROFS_FS >> select ZLIB_INFLATE if EROFS_FS_ZIP_DEFLATE >> select ZSTD_DECOMPRESS if EROFS_FS_ZIP_ZSTD >> 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 transparent compression and deduplication support to >> - improve storage density and maintain relatively high compression >> - ratios, and it implements in-place decompression to temporarily reuse >> - page cache for compressed data using proper strategies, which is >> - quite useful for ensuring guaranteed end-to-end runtime decompression >> + EROFS (Enhanced Read-Only File System) is a modern, lightweight, >> + secure read-only filesystem for various use cases, such as immutable >> + system images, container images, application sandboxes, and datasets. >> + >> + EROFS uses a flexible, hierarchical on-disk design so that features >> + can be enabled on demand: the core on-disk format is block-aligned in >> + order to perform optimally on all kinds of devices, including block >> + and memory-backed devices; the format is easy to parse and has zero >> + metadata redundancy, unlike generic filesystems, making it ideal for >> + for filesytem auditing and remote access; inline data, random-access > > duplicated 'for'? otherwise, looks good to me. Fixed and thanks for the review! > > Reviewed-by: Chao Yu <chao@kernel.org> > > Thanks, Thanks, Gao Xiang
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