en Copyright 2015 Java http://kernelsources.org:8080/source/history/linux/Documentation/filesystems/adding-new-filesystems.rst#e7d43a48a8e990b43ef8634248ee5b03f19ed3ea docs: add guidelines for submitting new filesystemsThis document is motivated by the ongoing maintenance burden thatabandoned and untestable filesystems impose on VFS developers, blockinginfrastructure changes such as folio conversions and iomap migration.This week alone, two new filesystems were proposed on linux-fsdevel(VMUFAT and FTRFS), highlighting the need for documented guidelinesthat new filesystem authors can refer to before submission.Multiple recent discussions on linux-fsdevel have touched on thecriteria for merging new filesystems and for deprecating old ones,covering topics such as modern VFS interface adoption, testability,userspace utilities, maintainer commitment, and user base viability.Add Documentation/filesystems/adding-new-filesystems.rst describingthe technical requirements and community expectations for merging anew filesystem into the kernel. The guidelines cover:- Alternatives to consider before proposing a new in-kernel filesystem- Technical requirements: modern VFS interfaces (iomap, folios, fs_context mount API), testability, and userspace utilities- Community expectations: identified maintainers, demonstrated commitment, sustained backing, and a clear user base- Ongoing obligations after merging, including the risk of deprecation for unmaintained filesystemsLink: https://lore.kernel.org/linux-fsdevel/20260411151155.321214-1-adrianmcmenamin@gmail.com/Link: https://lore.kernel.org/linux-fsdevel/20260413142357.515792-1-aurelien@hackers.camp/Link: https://lore.kernel.org/linux-fsdevel/yndtg2jbj55fzd2kkhsmel4pp5ll5xfvfiaqh24tdct3jiqosd@jzbfzf3rrxrd/Link: https://lore.kernel.org/linux-fsdevel/20260124091742.GA43313@macsyma.local/Link: https://lore.kernel.org/lkml/20260111140345.3866-1-linkinjeon@kernel.org/Cc: Christian Brauner <brauner@kernel.org>Cc: Alexander Viro <viro@zeniv.linux.org.uk>Cc: Jan Kara <jack@suse.cz>Cc: Theodore Tso <tytso@mit.edu>Cc: Christoph Hellwig <hch@lst.de>Cc: Darrick J. Wong <djwong@kernel.org>Cc: Matthew Wilcox <willy@infradead.org>Assisted-by: Cursor:claude-4-opusSigned-off-by: Amir Goldstein <amir73il@gmail.com>Link: https://patch.msgid.link/20260422125212.1743006-1-amir73il@gmail.comReviewed-by: Jan Kara <jack@suse.cz>Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org> List of files: /linux/Documentation/filesystems/adding-new-filesystems.rst Wed, 22 Apr 2026 14:52:12 +0200 Amir Goldstein <amir73il@gmail.com>