Userspace utilities to manage btrfs filesystems
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Qu Wenruo 66dad3a8f5 btrfs-progs: fix a false alert on an uninitialized variable when BUG_ON() is involved
[FALSE ALERT]
Clang 15.0.7 gives the following false alert in get_dev_extent_len():

  kernel-shared/extent-tree.c:3328:2: warning: variable 'div' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
          default:
          ^~~~~~~
  kernel-shared/extent-tree.c:3332:24: note: uninitialized use occurs here
          return map->ce.size / div;
                                ^~~
  kernel-shared/extent-tree.c:3311:9: note: initialize the variable 'div' to silence this warning
          int div;
                 ^
                  = 0

And one in btrfs_stripe_length() too:

  kernel-shared/volumes.c:2781:2: warning: variable 'stripe_len' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
          default:
          ^~~~~~~
  kernel-shared/volumes.c:2785:9: note: uninitialized use occurs here
          return stripe_len;
                 ^~~~~~~~~~
  kernel-shared/volumes.c:2754:16: note: initialize the variable 'stripe_len' to silence this warning
          u64 stripe_len;
                        ^
                         = 0

[CAUSE]
Clang doesn't really understand what BUG_ON() means, thus in that
default case, we won't get uninitialized value but crash directly.

[FIX]
Silent the errors by assigning the default value properly using the
value of SINGLE profile.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-02-18 17:44:02 +01:00
check btrfs-progs: check: enhance the error output for backref mismatch 2023-01-25 16:19:59 +01:00
ci btrfs-progs: ci: fix image updater script 2022-10-11 09:06:13 +02:00
cmds btrfs-progs: receive: fix a corruption when decompressing zstd extents 2023-02-18 17:44:02 +01:00
common btrfs-progs: help: change how padding is printed 2023-01-25 19:55:47 +01:00
convert btrfs-progs: mkfs: fix a stack over-flow when features string are too long 2022-10-11 09:08:12 +02:00
crypto btrfs-progs: use error helper for messages in non-kernel code 2022-10-11 09:08:07 +02:00
Documentation btrfs-progs: docs: describe formatting of sizes 2023-01-25 16:20:36 +01:00
image btrfs-progs: image: use help and cmd_struct for printing help text 2023-02-18 17:44:02 +01:00
kernel-lib btrfs-progs: properly handle degraded raid56 reads 2022-11-24 17:29:12 +01:00
kernel-shared btrfs-progs: fix a false alert on an uninitialized variable when BUG_ON() is involved 2023-02-18 17:44:02 +01:00
libbtrfs btrfs-progs: libbtrfs: move libbtrfs.sym to the directory 2023-01-05 14:23:46 +01:00
libbtrfsutil btrfs-progs: make btrfs_qgroup_level helper match the kernel 2022-11-28 18:57:43 +01:00
m4 btrfs-progs: build: add m4 macros for builtin detection 2022-08-16 15:18:12 +02:00
mkfs btrfs-progs: mkfs: convert help text to option formatter 2023-01-25 19:55:47 +01:00
tests btrfs-progs: libbtrfs: move version.h to the directory 2023-01-05 14:18:07 +01:00
tune btrfs-progs: tune: use help and cmd_struct for printing help text 2023-02-18 17:44:02 +01:00
.editorconfig btrfs-progs: add basic .editorconfig 2020-08-31 17:01:02 +02:00
.gitignore btrfs-progs: libbtrfs: move version.h to the directory 2023-01-05 14:18:07 +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
autogen.sh
btrfs-completion btrfs-progs: inspect: new command map-swapfile 2022-12-06 21:03:31 +01:00
btrfs-corrupt-block.c btrfs-progs: corrupt-block: fix the mismatch in --root and -r options 2022-12-20 20:49:13 +01:00
btrfs-crc.c btrfs-progs: move crc32c implementation to crypto/ 2019-11-18 19:20:02 +01:00
btrfs-debugfs btrfs-progs: port btrfs-debugfs to python3 2020-07-02 22:24:33 +02:00
btrfs-find-root.c btrfs-progs: map-logical: use message helpers for error messages 2022-10-11 09:08:07 +02:00
btrfs-fragments.c btrfs-progs: reorder includes in standalone tools 2022-10-11 09:06:12 +02:00
btrfs-map-logical.c btrfs-progs: kernel-lib: remove radix-tree 2022-10-11 09:08:07 +02:00
btrfs-sb-mod.c btrfs-progs: reorder includes in standalone tools 2022-10-11 09:06:12 +02:00
btrfs-select-super.c btrfs-progs: remove unnecessary casts for u64 2022-10-11 09:08:09 +02:00
btrfs.c btrfs-progs: add new group reflink and command 2022-12-07 01:43:30 +01:00
CHANGES btrfs-progs: update CHANGES for 6.1.3 2023-01-25 16:55:54 +01:00
configure.ac btrfs-progs: libbtrfs: move version.h to the directory 2023-01-05 14:18:07 +01:00
COPYING
fsck.btrfs
INSTALL btrfs-progs: docs: update documentation site references in manual pages 2022-10-11 09:08:12 +02:00
ioctl.h Revert "btrfs-progs: rename qgroup items to match the kernel naming scheme" 2023-01-03 13:10:54 +01:00
kerncompat.h btrfs-progs: kerncompat: hide definition of __init 2023-01-03 17:24:36 +01:00
Makefile btrfs-progs: tune: factor out checksum change to own file 2023-02-18 17:44:01 +01:00
Makefile.extrawarn btrfs-progs: build: disable -Waddress-of-packed-member by default 2019-06-14 15:09:53 +02:00
Makefile.inc.in btrfs-progs: build: rename compression support variables 2022-08-16 15:18:11 +02:00
quick-test.c btrfs-progs: kernel-lib: remove radix-tree 2022-10-11 09:08:07 +02:00
README.md btrfs-progs: docs: update documentation site references in manual pages 2022-10-11 09:08:12 +02:00
show-blocks
VERSION Btrfs progs v6.1.3 2023-01-25 19:39:27 +01:00

Btrfs-progs coverity status

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 and tests/README.md for testing 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 wiki.

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:

  • github issue tracker
  • to the mailing list linux-btrfs@vger.kernel.org -- (not required to subscribe), beware that the mail might get overlooked in other traffic
  • IRC (irc.libera.chat #btrfs) -- good for discussions eg. if a bug is already known, but reports could miss developers' attention
  • bugzilla.kernel.org -- (requires registration), set the product to Filesystems and component Btrfs, please put 'btrfs-progs' into the subject so it's clear that it's not a kernel bug report

Development

The patch submissions, development or general discussions take place at linux-btrfs@vger.kernel.org mailinglist, subsciption is not required to post.

The GitHub pull requests will not be accepted directly, the preferred way is to send patches to the mailinglist instead. You can link to a branch in any git repository if the mails do not make it to the mailinglist or just for convenience (makes it easier to test).

The development model of btrfs-progs shares a lot with the kernel model. The github way is different in some ways. We, the upstream community, expect that the patches meet some criteria (often lacking in github contributions):

  • one logical change per patch: eg. not mixing bugfixes, cleanups, features etc., sometimes it's not clear and will be usually pointed out during reviews
  • proper subject line: eg. 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: 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

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 testing documentation can be found in tests/ and continuous integration/container images in ci/.

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 mailinglist. Pointing out typos via IRC also works, although might get accidentally lost in the noise.

Documents 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 rescure or limited environments harder. The implementations are portable and not optimized for speed nor accelerated. Optionally it's possible to use libgcrypt, libsodium or libkcapi implementations.

Some other code is borrowed from kernel, eg. the raid5 tables or data structure implementation.

References