btrfs-progs-6.3

Introduction to btrfs-progs

The btrfs-progs package contains administration and debugging tools for the B-tree file system (btrfs).

[Note]

Note

Development versions of BLFS may not build or run some packages properly if dependencies have been updated since the most recent stable versions of the book.

Package Information

Btrfs-progs Dependencies

Required

LZO-2.10

Optional

LVM2-2.03.21 (dmsetup is used in tests), reiserfsprogs-3.6.27 (for tests), and sphinx-7.0.0 (required to build documentation)

User Notes: https://wiki.linuxfromscratch.org/blfs/wiki/btrfs-progs

Kernel Configuration

Enable the following option in the kernel configuration and recompile the kernel:

File systems --->
  <*/M> Btrfs filesystem support [CONFIG_BTRFS_FS]

In addition to the above and to the options required for LVM2-2.03.21 and reiserfsprogs-3.6.27, the following options must be enabled for running tests:

File systems  --->
  [*]   Btrfs POSIX Access Control Lists      [CONFIG_BTRFS_FS_POSIX_ACL]
  [*]   ReiserFS extended attributes          [CONFIG_REISERFS_FS_XATTR]
  [*]     ReiserFS POSIX Access Control Lists [CONFIG_REISERFS_FS_POSIX_ACL]

Installation of btrfs-progs

Install btrfs-progs by running the following commands:

./configure --prefix=/usr           \
            --disable-static        \
            --disable-documentation &&
make
[Note]

Note

Some tests require grep built with perl regular expressions. To obtain this, rebuild grep with the LFS Chapter 8 instructions after installing pcre2-10.42.

Before running tests, build a support program:

make fssum

To test the results, issue (as the root user):

pushd tests
   ./fsck-tests.sh
   ./mkfs-tests.sh
   ./cli-tests.sh
   sed 's/,orphan_file//' /etc/mke2fs.conf >./custom_mke2fs.conf &&
   export MKE2FS_CONFIG=$PWD/custom_mke2fs.conf                  &&
   ./convert-tests.sh
   unset MKE2FS_CONFIG && rm custom_mke2fs.conf
   ./misc-tests.sh
   ./fuzz-tests.sh
popd
[Note]

Note

If the above mentioned kernel options are not enabled, some tests fail, and prevent all the remaining tests to run because the test disk image is not cleanly unmounted.

The mkfs test 025-zoned-parallel is known to fail.

Install the package as the root user:

make install

If you have passed --disable-documentation to configure and you need the manual pages, install them by running, as the root user:

for i in 5 8; do
   install Documentation/*.$i /usr/share/man/man$i
done

Command Explanations

--disable-static: This switch prevents installation of static versions of the libraries.

--disable-documentation: This switch disables rebuilding the manual pages, because it requires sphinx-7.0.0.

sed 's/,orphan_file//" ...: In this version of btrfs-progs, the btrfs-convert program produces a btrfs filesystem containing errors if converting from an ext4 filesystem created with the orphan_file feature. This command creates a custom configuration file that prevents creating a filesystem with this feature.

Using the btrfs-convert Program

This version of btrfs-progs does not convert correctly ext4 filesystems to btrfs if the ext4 orphan_file feature is turned on. If you happen to convert such a filesystem, you need to first run:

tune2fs -O ^orphan_file /dev/sdxx

where /dev/sdxx is the partition of the filesystem you want to convert.

Contents

Installed Programs: btrfs, btrfs-convert, btrfs-find-root, btrfs-image, btrfs-map-logical, btrfs-select-super, btrfsck (link to btrfs), btrfstune, fsck.btrfs, and mkfs.btrfs
Installed Libraries: libbtrfs.so and libbtrfsutil.so
Installed Directories: /usr/include/btrfs

Short Descriptions

btrfs

is the main interface into btrfs filesystem operations

btrfs-convert

converts from an ext2/3/4 or reiserfs filesystem to btrfs (see the section called “Using the btrfs-convert Program” above)

btrfs-find-root

is a filter to find btrfs root

btrfs-map-logical

maps btrfs logical extent to physical extent

btrfs-select-super

overwrites the primary superblock with a backup copy

btrfstune

tunes various filesystem parameters

fsck.btrfs

does nothing, but is present for consistency with fstab

mkfs.btrfs

creates a btrfs file system