Userspace utilities to manage btrfs filesystems
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Qu Wenruo 2f8a6ee294 btrfs-progs: fix the conflicting super block flags
[BUG]
There is a bug report that a canceled checksum conversion (still
experimental feature) resulted in unexpected super flags:

csum_type		0 (crc32c)
csum_size		4
csum			0x14973811 [match]
bytenr			65536
flags			0x1000000001
			( WRITTEN |
			  CHANGING_FSID_V2 )
magic			_BHRfS_M [match]

While for a filesystem under checksum conversion it should have either
CHANGING_DATA_CSUM or CHANGING_META_CSUM.

[CAUSE]
It turns out that, due to btrfs-progs keeps its own extra flags inside
its own ctree.h headers, not the shared uapi headers, we have
conflicting super flags:

kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_METADUMP_V2	(1ULL << 34)
kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_CHANGING_FSID	(1ULL << 35)
kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 (1ULL << 36)
kernel-shared/ctree.h:#define BTRFS_SUPER_FLAG_CHANGING_DATA_CSUM	(1ULL << 36)
kernel-shared/ctree.h:#define BTRFS_SUPER_FLAG_CHANGING_META_CSUM	(1ULL << 37)

Note that CHANGING_FSID_V2 is conflicting with CHANGING_DATA_CSUM.

[FIX]
Cross port the proper updated uapi headers into btrfs-progs, and remove
the definition from ctree.h.

This would change the value for CHANGING_DATA_CSUM and
CHANGING_META_CSUM, but considering they are experimental features, and
kernel would reject them anyway, the damage is not that huge and we can
accept such change before exposing it to end users.

Pull-request: #810
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-06-24 19:17:49 +02:00
.github/workflows btrfs-progs: ci: enable sanitizer checks for master branch 2024-06-07 01:14:08 +02:00
Documentation btrfs-progs: docs: update 6.9 contribution graphs 2024-06-03 23:01:11 +02:00
check btrfs-progs: check: original, detect and repair ram_bytes mismatch 2024-05-03 15:30:26 +02:00
ci btrfs-progs: ci: enable gcc 14 on Tumbleweed 2024-04-30 19:34:52 +02:00
cmds btrfs-progs: use unaligned LE access almost everywhere 2024-05-30 18:57:10 +02:00
common btrfs-progs: support byte length for zone resetting 2024-06-03 21:26:39 +02:00
config btrfs-progs: detect PCLMUL CPU support for accelerated crc32c 2023-09-13 00:38:50 +02:00
convert btrfs-progs: convert: rework file extent iteration to handle unwritten extents 2024-06-03 22:10:22 +02:00
crypto btrfs-progs: crypto: add openssl as crypto provider 2023-11-30 22:04:45 +01:00
image btrfs-progs: use unaligned LE access almost everywhere 2024-05-30 18:57:10 +02:00
include btrfs-progs: use unsigned types for bit shifts 2024-03-12 22:05:09 +01:00
kernel-lib btrfs-progs: clean up includes, using include-what-you-use 2023-10-03 01:11:57 +02:00
kernel-shared btrfs-progs: fix the conflicting super block flags 2024-06-24 19:17:49 +02:00
libbtrfs libbtrfs: fix potentially unaligned access 2024-05-25 00:37:52 +02:00
libbtrfsutil libbtrfsutil: bump version to 1.3.1 2024-05-29 22:37:59 +02:00
mkfs btrfs-progs: mkfs: align byte_count with sectorsize and zone size 2024-06-03 21:17:34 +02:00
tests btrfs-progs: tests: do not use async discard for misc/004 2024-06-24 19:17:45 +02:00
tune btrfs-progs: change-csum: handle finished dev-replace correctly 2024-06-03 21:59:43 +02:00
.editorconfig
.gitignore btrfs-progs: docs: placeholder for contents.rst file on older sphinx version 2024-01-11 17:04:48 +01:00
.readthedocs.yaml btrfs-progs: docs: add config file for readthedocs.io 2023-12-05 16:36:24 +01:00
64-btrfs-dm.rules
64-btrfs-zoned.rules btrfs-progs: add udev rule to use mq-deadline on zoned btrfs 2022-02-01 18:41:43 +01:00
CHANGES btrfs-progs: update CHANGES for 6.9 2024-06-07 17:46:47 +02:00
COPYING
INSTALL btrfs-progs: INSTALL: document libraries needed for fsstress 2024-05-31 17:47:40 +02:00
Makefile btrfs-progs: build: fix minor typos in cleaning messages 2024-06-03 21:00:29 +02:00
Makefile.extrawarn btrfs-progs: enable -Wshadow for default build 2023-10-10 19:23:10 +02:00
Makefile.inc.in libbtrfs: create all .so links 2024-05-25 01:21:22 +02:00
README.md btrfs-progs: README: fix typo in changelog link 2024-02-08 08:30:37 +01:00
VERSION Btrfs progs v6.9 2024-06-07 17:47:14 +02:00
autogen.sh btrfs-progs: build: reuse config/ directory for m4 macros 2023-05-26 21:08:17 +02:00
btrfs-completion btrfs-progs: move space cache removal to rescue group 2023-11-03 18:04:37 +01:00
btrfs-corrupt-block.c btrfs-progs: corrupt-block: fix memory leak in debug_corrupt_sector() 2024-06-05 19:45:34 +02:00
btrfs-crc.c
btrfs-debugfs
btrfs-find-root.c btrfs-progs: clean up includes, using include-what-you-use 2023-10-03 01:11:57 +02:00
btrfs-map-logical.c btrfs-progs: clean up includes, using include-what-you-use 2023-10-03 01:11:57 +02:00
btrfs-sb-mod.c btrfs-progs: sb-mod: fix build after removing log_root_transid 2023-10-21 15:51:07 +02:00
btrfs-select-super.c btrfs-progs: clean up includes, using include-what-you-use 2023-10-03 01:11:57 +02:00
btrfs.c btrfs-progs: add support for dry-run options 2023-11-03 18:04:37 +01:00
configure.ac btrfs-progs: build: use -O2 by default 2024-06-07 01:14:08 +02:00
fsck.btrfs
inject-error btrfs-progs: add error injection helper script 2023-07-27 14:45:29 +02:00
show-blocks

README.md

Btrfs-progs

devel coverage codecov static release

Userspace utilities to manage btrfs filesystems. License: GPLv2.

Btrfs is a copy on write (COW) filesystem for Linux aimed at implementing advanced features while focusing on fault tolerance, repair and easy administration.

This repository hosts following utilities and also documentation:

See INSTALL for build instructions, tests/README.md for testing information and ci/README.md for CI information.

Release cycle

The major version releases are time-based and follow the cycle of the linux kernel releases. The cycle usually takes 2 months. A minor version releases may happen in the meantime if there are bug fixes or minor useful improvements queued.

The release tags are signed with a GPG key ID F2B4 1200 C54E FB30 380C 1756 C565 D5F9 D76D 583B, release tarballs are hosted at kernel.org. See file CHANGES or changelogs on RTD.

Releases with changelog are also published at Github release page.

Static binaries

For each release there are static binaries of btrfs and btrfs.box provided. These can be used in rescue environments and are built for x86_64 architecture (with maximum backward compatibility), inside the Github Actions workflow. The btrfs.box is an all-in-one tool in the busybox style, the functionality is determined by the binary names (either symlink, hradlink or a file copy).

Feature compatibility

The btrfs-progs of version X.Y declare support of kernel features of the same version. New progs on old kernel are expected to work, limited only by features provided by the kernel.

Build compatibility

Build is supported on the GNU C library as the primary target, and on the musl libc.

The supported compilers are gcc (minimal version 4.8) and clang (minimal version 3.4).

Build tests are done on several distributions, see Github actions workflow.

Reporting bugs

There are several ways, each has its own specifics and audience that can give feedback or work on a fix. The following list is sorted in the order of preference:

Development

The development takes place in the mailing list (linux-btrfs@vger.kernel.org) or at Github (issues, pull requests). Changes should be split to logical parts if possible, documentation may be included in the same patch as to code or separately.

The development model of btrfs-progs shares a lot with the kernel model. The

  • one logical change per patch: e.g. not mixing bugfixes, cleanups, features etc., sometimes it's not clear and will be usually pointed out during reviews
  • proper subject line: e.g. prefix with btrfs-progs: subpart, ... , descriptive yet not too long, see git log --oneline for some inspiration
  • proper changelog: the changelogs are often missing or lacking explanation why the change was made, or how is something broken, what are user-visible effects of the bug or the fix, how does an improvement help or the intended usecase
  • the Signed-off-by line is not mandatory for less significant changes (typos, documentation) but is desired as this documents who authored the change, you can read more about the The Developer's Certificate of Origin (chapter 11)
    • if you are not used to the signed-off style, your contributions won't be rejected just because of it's missing, the Author: tag will be added as a substitute in order to allow contributions without much bothering with formalities

Pull requests

The pull requests on Github may be used for code or documentation contributions. There are basic build checks enabled in the Github actions CI for pull requests. The status can be checked at the workflow page.

  • open a PR against branches devel or master
  • push update to the same branch if you need to
  • close the PR in case it's wrong, a mistake or needs rework
  • if you're sure the changes don't need a CI build verification, please add [skip ci] to the changelog

Source code coding style and preferences follow the kernel coding style. You can find the editor settings in .editorconfig and use the EditorConfig plugin to let your editor use that, or update your editor settings manually.

Testing

The documentation for writing and running tests can be found in tests/ and continuous integration/container images in ci/.

Development branches are tested by Github Action workflows.

Code coverage provided by codecov.io can be found here.

Documentation updates

Documentation fixes or updates do not need much explanation so sticking to the code rules in the previous section is not necessary. GitHub pull requests are OK, patches could be sent to me directly and not required to be also in the mailing list. Pointing out typos via IRC also works, although might get accidentally lost in the noise.

Documentation sources are written in RST and built by sphinx.

Third-party sources

Build dependencies are listed in INSTALL. Implementation of checksum/hash functions is provided by copies of the respective sources to avoid adding dependencies that would make deployments in rescue or limited environments harder. The implementations are portable and there are optimized versions for some architectures. Optionally it's possible to use libgcrypt, libsodium, libkcapi, Botan or OpenSSL implementations.

The builtin implemtations uses the following sources: CRC32C, XXHASH, SHA256, BLAKE2.

Some other code is borrowed from kernel, eg. the raid5 tables or data structure implementation (list, rb-tree).

References