flatcar · ananthb · Jul 8, 2026 · Jul 8, 2026 · Jul 8, 2026 · Jul 8, 2026
@@ -1,4 +1,5 @@
 EXTRA_SYSEXTS=(
+  "bcachefs|sys-fs/bcachefs-tools|-modules|amd64"
   "overlaybd|sys-fs/overlaybd,app-containers/accelerated-container-image"
   "incus|app-containers/incus"
   "nvidia-drivers-535|x11-drivers/nvidia-drivers:0/535|-kernel-open persistenced|amd64"

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+set -euo pipefail
+rootfs="${1}"
+
+pushd "${rootfs}"
+
+# Drop dev/debug/initramfs files — the sysext only needs runtime bits.
+rm -rf ./usr/{lib/debug/,lib64/cmake/,include/}
+rm -rf ./usr/lib/dracut/
+rm -rf ./usr/share/initramfs-tools
+rm -rf ./usr/src
+rm -rf ./usr/share/man
+rm -rf ./usr/share/doc
+rm -rf ./usr/lib/pkgconfig
+rm -rf ./usr/lib64/pkgconfig
+
+# /usr/sbin on Flatcar is a symlink to /usr/bin; shipping a /usr/sbin
+# directory in a sysext would clobber the symlink at merge time. Relocate
+# anything the tools ebuild installed there. `cp -a src/. dst/` includes
+# dotfiles (Portage `.keep*` placeholders) so nothing lingers to make the
+# subsequent `rm -rf` racy.
+if [ -d ./usr/sbin ]; then
+  mkdir -p ./usr/bin
+  cp -a ./usr/sbin/. ./usr/bin/
+  rm -rf ./usr/sbin
+fi
+
+popd
@@ -0,0 +1 @@
+- Enabled the in-tree bcachefs kernel module (`CONFIG_BCACHEFS_FS=m` with POSIX ACLs) and provided a companion bcachefs Flatcar extension as an optional systemd-sysext image with the release. Write `bcachefs` to `/etc/flatcar/enabled-sysext.conf` through Ignition and the sysext will be installed during provisioning; it ships the userspace utilities (`mkfs.bcachefs`, `mount.bcachefs`, ...) that pair with the kernel module. bcachefs is still experimental (pre-1.0 on-disk format) and is not supported for the root partition.
@@ -24,6 +24,8 @@ CONFIG_AUTOFS_FS=y
 CONFIG_B44=m
 # CONFIG_BACKLIGHT_CLASS_DEVICE is not set
 CONFIG_BCACHE=m
+CONFIG_BCACHEFS_FS=m
+CONFIG_BCACHEFS_POSIX_ACL=y
 CONFIG_BCM87XX_PHY=m
 CONFIG_BFQ_GROUP_IOSCHED=y
 CONFIG_BINFMT_MISC=m

@@ -0,0 +1,350 @@
+# Copyright 1999-2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+CRATES="
+	aho-corasick@1.1.3
+	android_system_properties@0.1.5
+	anstream@0.6.15
+	anstyle-parse@0.2.5
+	anstyle-query@1.1.1
+	anstyle-wincon@3.0.4
+	anstyle@1.0.8
+	anyhow@1.0.89
+	ascii@1.1.0
+	autocfg@1.5.0
+	bindgen@0.72.1
+	bitfield@0.14.0
+	bitflags@1.3.2
+	bitflags@2.11.0
+	bumpalo@3.19.1
+	cc@1.2.55
+	cexpr@0.6.0
+	cfg-if@1.0.0
+	cfg_aliases@0.2.1
+	chrono@0.4.43
+	chunked_transfer@1.5.0
+	clang-sys@1.8.1
+	clap@4.5.20
+	clap_builder@4.5.20
+	clap_complete@4.5.33
+	clap_derive@4.5.18
+	clap_lex@0.7.2
+	colorchoice@1.0.2
+	core-foundation-sys@0.8.7
+	crossterm@0.28.1
+	either@1.13.0
+	env_logger@0.10.2
+	equivalent@1.0.2
+	errno@0.3.9
+	fiemap@0.2.0
+	find-msvc-tools@0.1.9
+	fuser@0.17.0
+	getrandom@0.2.17
+	glob@0.3.1
+	hashbrown@0.16.1
+	heck@0.5.0
+	httpdate@1.0.3
+	iana-time-zone-haiku@0.1.2
+	iana-time-zone@0.1.65
+	indexmap@2.13.0
+	is_terminal_polyfill@1.70.1
+	itertools@0.12.1
+	itoa@1.0.17
+	js-sys@0.3.85
+	libc@0.2.180
+	libloading@0.8.5
+	libudev-sys@0.1.4
+	linux-raw-sys@0.4.14
+	lock_api@0.4.14
+	log@0.4.22
+	memchr@2.7.4
+	memoffset@0.9.1
+	minimal-lexical@0.2.1
+	mio@1.1.1
+	nix@0.30.1
+	nom@7.1.3
+	num-traits@0.2.19
+	num_enum@0.7.5
+	num_enum_derive@0.7.5
+	once_cell@1.20.2
+	owo-colors@4.1.0
+	page_size@0.6.0
+	parking_lot@0.12.5
+	parking_lot_core@0.9.12
+	paste@1.0.15
+	pkg-config@0.3.31
+	prettyplease@0.2.22
+	proc-macro-crate@3.4.0
+	proc-macro2@1.0.87
+	quote@1.0.37
+	redox_syscall@0.5.18
+	ref-cast-impl@1.0.25
+	ref-cast@1.0.25
+	regex-automata@0.4.8
+	regex-syntax@0.8.5
+	regex@1.11.0
+	rustc-demangle@0.1.27
+	rustc-hash@2.1.1
+	rustix@0.38.37
+	rustversion@1.0.17
+	ryu@1.0.22
+	scopeguard@1.2.0
+	serde@1.0.228
+	serde_core@1.0.228
+	serde_derive@1.0.228
+	serde_json@1.0.143
+	shlex@1.3.0
+	signal-hook-mio@0.2.5
+	signal-hook-registry@1.4.8
+	signal-hook@0.3.18
+	smallvec@1.15.1
+	strsim@0.11.1
+	strum@0.26.3
+	strum_macros@0.26.4
+	syn@2.0.87
+	terminal_size@0.4.0
+	tiny_http@0.12.0
+	toml_datetime@0.7.5+spec-1.1.0
+	toml_edit@0.23.10+spec-1.0.0
+	toml_parser@1.0.9+spec-1.1.0
+	udev@0.7.0
+	unicode-ident@1.0.13
+	utf8parse@0.2.2
+	uuid@1.10.0
+	wasi@0.11.1+wasi-snapshot-preview1
+	wasm-bindgen-macro-support@0.2.108
+	wasm-bindgen-macro@0.2.108
+	wasm-bindgen-shared@0.2.108
+	wasm-bindgen@0.2.108
+	winapi-i686-pc-windows-gnu@0.4.0
+	winapi-x86_64-pc-windows-gnu@0.4.0
+	winapi@0.3.9
+	windows-core@0.62.2
+	windows-implement@0.60.2
+	windows-interface@0.59.3
+	windows-link@0.2.1
+	windows-result@0.4.1
+	windows-strings@0.5.1
+	windows-sys@0.52.0
+	windows-sys@0.59.0
+	windows-sys@0.61.2
+	windows-targets@0.52.6
+	windows_aarch64_gnullvm@0.52.6
+	windows_aarch64_msvc@0.52.6
+	windows_i686_gnu@0.52.6
+	windows_i686_gnullvm@0.52.6
+	windows_i686_msvc@0.52.6
+	windows_x86_64_gnu@0.52.6
+	windows_x86_64_gnullvm@0.52.6
+	windows_x86_64_msvc@0.52.6
+	winnow@0.7.14
+	zerocopy-derive@0.8.27
+	zerocopy@0.8.27
+	zeroize@1.8.1
+	zeroize_derive@1.4.2
+"
+
+LLVM_COMPAT=( {17..21} )
+MODULES_INITRAMFS_IUSE=+initramfs
+MODULES_KERNEL_MIN=6.16
+MODULES_OPTIONAL_IUSE=+modules
+PYTHON_COMPAT=( python3_{11..14} )
+RUST_MIN_VER="1.85.0"
+VERIFY_SIG_OPENPGP_KEY_PATH=/usr/share/openpgp-keys/kentoverstreet.asc
+
+inherit cargo flag-o-matic linux-mod-r1 llvm-r2 python-any-r1
+inherit shell-completion sysroot toolchain-funcs unpacker verify-sig
+
+DESCRIPTION="Tools for bcachefs"
+HOMEPAGE="https://bcachefs.org/"
+if [[ ${PV} == "9999" ]]; then
+	inherit git-r3
+	EGIT_REPO_URI="https://evilpiepirate.org/git/bcachefs-tools.git"
+else
+	SRC_URI="https://evilpiepirate.org/bcachefs-tools/bcachefs-tools-${PV}.tar.zst
+		${CARGO_CRATE_URIS}
+	"
+	SRC_URI+=" verify-sig? ( https://evilpiepirate.org/bcachefs-tools/bcachefs-tools-${PV}.tar.sign )"
+	S="${WORKDIR}/${P}"
+	KEYWORDS="~amd64 ~arm64"
+fi
+
+LICENSE="GPL-2"
+# Dependent crate licenses
+LICENSE+=" Apache-2.0 BSD ISC MIT Unicode-DFS-2016"
+SLOT="0"
+IUSE="debug llvm-libunwind verify-sig"
+RESTRICT="test"
+
+DEPEND="
+	app-arch/lz4:=
+	app-arch/zstd:=
+	dev-libs/libaio
+	dev-libs/libsodium:=
+	dev-libs/userspace-rcu:=
+	sys-apps/keyutils:=
+	sys-apps/util-linux
+	llvm-libunwind? ( llvm-runtimes/libunwind:= )
+	!llvm-libunwind? ( sys-libs/libunwind:= )
+	virtual/udev
+	virtual/zlib:=
+"
+
+RDEPEND="${DEPEND}"
+
+# Clang is required for bindgen
+BDEPEND="
+	${PYTHON_DEPS}
+	$(python_gen_any_dep '
+		dev-python/docutils[${PYTHON_USEDEP}]
+	')
+	$(unpacker_src_uri_depends)
+	$(llvm_gen_dep '
+		llvm-core/clang:${LLVM_SLOT}
+	')
+	elibc_musl? ( >=sys-libs/musl-1.2.5 )
+	virtual/pkgconfig
+	modules? ( >=sys-kernel/linux-headers-6.16.0 )
+	verify-sig? ( >=sec-keys/openpgp-keys-kentoverstreet-20241012 )
+"
+
+QA_FLAGS_IGNORED="/sbin/bcachefs"
+
+python_check_deps() {
+	python_has_version "dev-python/docutils[${PYTHON_USEDEP}]"
+}
+
+pkg_setup() {
+	llvm-r2_pkg_setup
+	python-any-r1_pkg_setup
+	rust_pkg_setup
+	if use modules; then
+		# grep -r 'depends on\|select ' ${S}/libbcachefs/Kconfig | grep -v '^#'
+		local CONFIG_CHECK="
+			!BCACHEFS_FS
+			BLOCK
+			EXPORTFS
+			CRC32
+			CRC64
+			FS_POSIX_ACL
+			LZ4_COMPRESS
+			LZ4_DECOMPRESS
+			LZ4HC_COMPRESS
+			ZLIB_DEFLATE
+			ZLIB_INFLATE
+			ZSTD_COMPRESS
+			ZSTD_DECOMPRESS
+			CRYPTO_LIB_SHA256
+			CRYPTO_LIB_CHACHA
+			CRYPTO_LIB_POLY1305
+			KEYS
+			RAID6_PQ
+			RUST
+			XOR_BLOCKS
+			XXHASH
+			SYMBOLIC_ERRNAME
+		"
+		use debug && CONFIG_CHECK+="
+			DEBUG_INFO
+			FRAME_POINTER
+			!DEBUG_INFO_REDUCED
+		"
+		linux-mod-r1_pkg_setup
+	fi
+}
+
+src_unpack() {
+	if [[ ${PV} == "9999" ]]; then
+		git-r3_src_unpack
+		S="${S}/src" cargo_live_src_unpack
+	else
+		if use verify-sig; then
+			# Upstream signs the uncompressed tarball. Stream-verify the
+			# detached signature while extracting the tarball via tee,
+			# leaving the source tree in place.
+			einfo "Verifying and unpacking ${P}.tar.zst ..."
+			verify-sig_verify_detached - "${DISTDIR}"/${P}.tar.sign \
+				< <(zstd -fdc "${DISTDIR}"/${P}.tar.zst | tee >(tar -xf -))
+			assert "Unpack failed"
+			# Filter the tarball and its detached signature out of ${A}
+			# so cargo_src_unpack doesn't re-extract the tarball or feed
+			# the .sign file to unpack (which would die).
+			local A=${A//${P}.tar.zst/}
+			A=${A//${P}.tar.sign/}
+		fi
+		# cargo_src_unpack extracts the vendored Cargo crates and, when
+		# not filtered above, the source tarball itself.
+		cargo_src_unpack
+	fi
+}
+
+src_prepare() {
+	default
+	tc-export CC
+
+	echo "${PV}" > .version || die
+	sed \
+		-e '/^CFLAGS/s:-O2::' \
+		-e '/^CFLAGS/s:-g::' \
+		-i Makefile || die
+
+	if use llvm-libunwind; then
+		sed -i s/libunwind// Makefile || die
+	fi
+
+	append-lfs-flags
+}
+
+src_configure() {
+	cargo_src_configure
+
+	MODULE_SRC="module/${PN%-*}-${PV}"
+	use modules && emake DESTDIR="${WORKDIR}" DKMSDIR="/${MODULE_SRC}" install_dkms
+}
+
+src_compile() {
+	export BUILD_VERBOSE=1
+	export VERSION=${PV}
+
+	local modlist=( "bcachefs=:../${MODULE_SRC}:../${MODULE_SRC}/src/fs/bcachefs" )
+	local modargs=(
+		KDIR=${KV_OUT_DIR}
+	)
+
+	# Makefile calls `cargo` directly, so make sure we set our rustflags (etc)
+	cargo_env emake bcachefs || die
+	use modules && linux-mod-r1_src_compile
+
+	# Recent versions mangle the 'bcachefs' symbolic link. Force the link
+	# unconditionally so this keeps working once upstream stops mangling.
+	ln -rsf target/release/bcachefs bcachefs || die
+
+	local shell
+	for shell in bash fish zsh; do
+		sysroot_try_run_prefixed ./bcachefs completions ${shell} > ${shell}.completion || die
+	done
+}
+
+src_install() {
+	into /
+	dosbin bcachefs
+
+	dosym bcachefs /sbin/fsck.bcachefs
+	dosym bcachefs /sbin/mkfs.bcachefs
+	dosym bcachefs /sbin/mount.bcachefs
+
+	# Uses a crate-based implementation of FUSE, no dependency on sys-fs/fuse and unconditionally included.
+	dosym bcachefs /sbin/fsck.fuse.bcachefs
+	dosym bcachefs /sbin/mkfs.fuse.bcachefs
+	dosym bcachefs /sbin/mount.fuse.bcachefs
+
+	newbashcomp bash.completion bcachefs
+	newfishcomp fish.completion bcachefs.fish
+	newzshcomp zsh.completion _bcachefs
+
+	doman bcachefs.8
+
+	use modules && linux-mod-r1_src_install
+}
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		- Enabled the in-tree bcachefs kernel module (`CONFIG_BCACHEFS_FS=m` with POSIX ACLs) and provided a companion bcachefs Flatcar extension as an optional systemd-sysext image with the release. Write `bcachefs` to `/etc/flatcar/enabled-sysext.conf` through Ignition and the sysext will be installed during provisioning; it ships the userspace utilities (`mkfs.bcachefs`, `mount.bcachefs`, ...) that pair with the kernel module. bcachefs is still experimental (pre-1.0 on-disk format) and is not supported for the root partition.
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