From nobody Fri Apr 3 20:53:02 2026 Received: from out30-113.freemail.mail.aliyun.com (out30-113.freemail.mail.aliyun.com [115.124.30.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB1A437BE66 for ; Mon, 23 Mar 2026 09:49:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.113 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774259348; cv=none; b=Nt7HhGMpUnh7ltrAasLskN8/I/3+UFCFhCnUoS9jJAk8Rv5lklwhgmOjfhI61JSIJ4ejG3+9ZYACnxJ9tlRhP9EzNZLfJ8c7N7TiZqzyPKZDREpZXdb9qLldPUOJNwvHBCSUPjv4yr36eyZiCPVOkxWL0VsucRMGkTmtpss8U8g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774259348; c=relaxed/simple; bh=RsSB0QS+kI1MPHWflQHcHNmy1+8AtJLBW2TZlLx78/Y=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=C6/JafsMKX8XeBXJySDZ1uILul5bumofEunZkySGYckzSyS1ZU227Dje0MvuuYICbNU5tW7MBSh7vM1Jfg+xRuvmXbEM8+XdWzX8n62XvxOHywp2W27EvjcMcFixXgkwHtGLp+RJNGvByZLCt0v5guWi6B0zkJ39Ox1rAs0qmBc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=c0NCXVoz; arc=none smtp.client-ip=115.124.30.113 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="c0NCXVoz" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1774259342; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=0KzACxuDuinzNW8y4KmDnlliv0Pog010pgubfK+alRU=; b=c0NCXVoz/zHPpBhG05wkyhNIGo6gzdqrZi7I2AEhafdVYw4VvjnSAo3QWVuYG5Qn7F83mRhx6oeoC3hU5aWGwLVUWlewx6p9SVYPZVLFrRILDSO2ZEARRLoYfrKoOyHHX0rTwakamk+4QbKoY9M5vtNhTCJ7xO8R9nvA9T872cA= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033045098064;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0X.W8c8F_1774259338; Received: from x31i01179.sqa.na131.tbsite.net(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0X.W8c8F_1774259338 cluster:ay36) by smtp.aliyun-inc.com; Mon, 23 Mar 2026 17:49:02 +0800 From: Gao Xiang To: linux-erofs@lists.ozlabs.org, Chao Yu Cc: LKML , Gao Xiang Subject: [PATCH] erofs: update the Kconfig description Date: Mon, 23 Mar 2026 17:48:57 +0800 Message-ID: <20260323094857.2187994-1-hsiangkao@linux.alibaba.com> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 Reviewed-by: Chao Yu --- 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. =20 - See the documentation at - and the web pages at for more details. + For more details, see the web pages at + and the documentation at . + + To compile EROFS filesystem support as a module, choose M here. The + module will be called erofs. =20 If unsure, say N. =20 @@ -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. =20 If you don't want to enable compression feature, say N. =20 --=20 2.43.5