diff --git a/pkgs/build-support/kernel/initrd-compressor-meta.nix b/pkgs/build-support/kernel/initrd-compressor-meta.nix new file mode 100644 index 00000000000..443e599a239 --- /dev/null +++ b/pkgs/build-support/kernel/initrd-compressor-meta.nix @@ -0,0 +1,53 @@ +rec { + cat = { + executable = pkgs: "cat"; + ubootName = "none"; + extension = ".cpio"; + }; + gzip = { + executable = pkgs: "${pkgs.gzip}/bin/gzip"; + defaultArgs = ["-9n"]; + ubootName = "gzip"; + extension = ".gz"; + }; + bzip2 = { + executable = pkgs: "${pkgs.bzip2}/bin/bzip2"; + ubootName = "bzip2"; + extension = ".bz2"; + }; + xz = { + executable = pkgs: "${pkgs.xz}/bin/xz"; + defaultArgs = ["--check=crc32" "--lzma2=dict=512KiB"]; + extension = ".xz"; + }; + lzma = { + executable = pkgs: "${pkgs.xz}/bin/lzma"; + defaultArgs = ["--check=crc32" "--lzma1=dict=512KiB"]; + ubootName = "lzma"; + extension = ".lzma"; + }; + lz4 = { + executable = pkgs: "${pkgs.lz4}/bin/lz4"; + defaultArgs = ["-l"]; + ubootName = "lz4"; + extension = ".lz4"; + }; + lzop = { + executable = pkgs: "${pkgs.lzop}/bin/lzop"; + ubootName = "lzo"; + extension = ".lzo"; + }; + zstd = { + executable = pkgs: "${pkgs.zstd}/bin/zstd"; + defaultArgs = ["-10"]; + ubootName = "zstd"; + extension = ".zst"; + }; + pigz = gzip // { + executable = pkgs: "${pkgs.pigz}/bin/pigz"; + }; + pixz = xz // { + executable = pkgs: "${pkgs.pixz}/bin/pixz"; + defaultArgs = []; + }; +} diff --git a/pkgs/build-support/kernel/make-initrd.nix b/pkgs/build-support/kernel/make-initrd.nix index f0a61d3476e..901eb311a88 100644 --- a/pkgs/build-support/kernel/make-initrd.nix +++ b/pkgs/build-support/kernel/make-initrd.nix @@ -1,24 +1,74 @@ -# Create an initial ramdisk containing the closure of the specified -# file system objects. An initial ramdisk is used during the initial +# Create an initramfs containing the closure of the specified +# file system objects. An initramfs is used during the initial # stages of booting a Linux system. It is loaded by the boot loader # along with the kernel image. It's supposed to contain everything # (such as kernel modules) necessary to allow us to mount the root # file system. Once the root file system is mounted, the `real' boot # script can be called. # -# An initrd is really just a gzipped cpio archive. -# -# Symlinks are created for each top-level file system object. E.g., -# `contents = {object = ...; symlink = /init;}' is a typical -# argument. - -{ stdenvNoCC, perl, cpio, contents, ubootTools +# An initramfs is a cpio archive, and may be compressed with a number +# of algorithms. +let + # Some metadata on various compression programs, relevant to naming + # the initramfs file and, if applicable, generating a u-boot image + # from it. + compressors = import ./initrd-compressor-meta.nix; + # Get the basename of the actual compression program from the whole + # compression command, for the purpose of guessing the u-boot + # compression type and filename extension. + compressorName = fullCommand: builtins.elemAt (builtins.match "([^ ]*/)?([^ ]+).*" fullCommand) 1; +in +{ stdenvNoCC, perl, cpio, ubootTools, lib, pkgsBuildHost +# Name of the derivation (not of the resulting file!) , name ? "initrd" -, compressor ? "gzip -9n" + +# Program used to compress the cpio archive; use "cat" for no compression. +# This can also be a function which takes a package set and returns the path to the compressor, +# such as `pkgs: "${pkgs.lzop}/bin/lzop"`. +, compressor ? "gzip" +, _compressorFunction ? + if lib.isFunction compressor then compressor + else if ! builtins.hasContext compressor && builtins.hasAttr compressor compressors then compressors.${compressor}.executable + else _: compressor +, _compressorExecutable ? _compressorFunction pkgsBuildHost +, _compressorName ? compressorName _compressorExecutable +, _compressorMeta ? compressors.${_compressorName} or {} + +# List of arguments to pass to the compressor program, or null to use its defaults +, compressorArgs ? null +, _compressorArgsReal ? if compressorArgs == null then _compressorMeta.defaultArgs or [] else compressorArgs + +# Filename extension to use for the compressed initramfs. This is +# included for clarity, but $out/initrd will always be a symlink to +# the final image. +# If this isn't guessed, you may want to complete the metadata above and send a PR :) +, extension ? _compressorMeta.extension or + (throw "Unrecognised compressor ${_compressorName}, please specify filename extension") + +# List of { object = path_or_derivation; symlink = "/path"; } +# The paths are copied into the initramfs in their nix store path +# form, then linked at the root according to `symlink`. +, contents + +# List of uncompressed cpio files to prepend to the initramfs. This +# can be used to add files in specified paths without them becoming +# symlinks to store paths. , prepend ? [] -, lib + +# Whether to wrap the initramfs in a u-boot image. , makeUInitrd ? stdenvNoCC.hostPlatform.platform.kernelTarget == "uImage" -, uInitrdArch ? stdenvNoCC.hostPlatform.parsed.cpu.family + +# If generating a u-boot image, the architecture to use. The default +# guess may not align with u-boot's nomenclature correctly, so it can +# be overridden. +# See https://gitlab.denx.de/u-boot/u-boot/-/blob/9bfb567e5f1bfe7de8eb41f8c6d00f49d2b9a426/common/image.c#L81-106 for a list. +, uInitrdArch ? stdenvNoCC.hostPlatform.kernelArch + +# The name of the compression, as recognised by u-boot. +# See https://gitlab.denx.de/u-boot/u-boot/-/blob/9bfb567e5f1bfe7de8eb41f8c6d00f49d2b9a426/common/image.c#L195-204 for a list. +# If this isn't guessed, you may want to complete the metadata above and send a PR :) +, uInitrdCompression ? _compressorMeta.ubootName or + (throw "Unrecognised compressor ${_compressorName}, please specify uInitrdCompression") }: let # !!! Move this into a public lib function, it is probably useful for others @@ -26,13 +76,26 @@ let lib.concatStringsSep "-" (filter (x: !(isList x)) (split "[^a-zA-Z0-9_=.?-]+" x)); in stdenvNoCC.mkDerivation rec { - inherit name makeUInitrd uInitrdArch; + inherit name makeUInitrd extension uInitrdArch prepend; + + ${if makeUInitrd then "uinitrdCompression" else null} = uInitrdCompression; builder = ./make-initrd.sh; nativeBuildInputs = [ perl cpio ] ++ stdenvNoCC.lib.optional makeUInitrd ubootTools; + compress = "${_compressorExecutable} ${lib.escapeShellArgs _compressorArgsReal}"; + + # Pass the function through, for reuse in append-initrd-secrets. The + # function is used instead of the string, in order to support + # cross-compilation (append-initrd-secrets running on a different + # architecture than what the main initramfs is built on). + passthru = { + compressorExecutableFunction = _compressorFunction; + compressorArgs = _compressorArgsReal; + }; + # !!! should use XML. objects = map (x: x.object) contents; symlinks = map (x: x.symlink) contents; @@ -47,6 +110,4 @@ in stdenvNoCC.mkDerivation rec { contents (lib.range 0 (lib.length contents - 1)); pathsFromGraph = ./paths-from-graph.pl; - - inherit compressor prepend; } diff --git a/pkgs/build-support/kernel/make-initrd.sh b/pkgs/build-support/kernel/make-initrd.sh index 8243736ba46..c0619ef14ae 100644 --- a/pkgs/build-support/kernel/make-initrd.sh +++ b/pkgs/build-support/kernel/make-initrd.sh @@ -40,9 +40,12 @@ for PREP in $prepend; do cat $PREP >> $out/initrd done (cd root && find * .[^.*] -exec touch -h -d '@1' '{}' +) -(cd root && find * .[^.*] -print0 | sort -z | cpio -o -H newc -R +0:+0 --reproducible --null | $compressor >> $out/initrd) +(cd root && find * .[^.*] -print0 | sort -z | cpio -o -H newc -R +0:+0 --reproducible --null | eval -- $compress >> "$out/initrd") if [ -n "$makeUInitrd" ]; then - mv $out/initrd $out/initrd.gz - mkimage -A $uInitrdArch -O linux -T ramdisk -C gzip -d $out/initrd.gz $out/initrd + mkimage -A $uInitrdArch -O linux -T ramdisk -C "$uInitrdCompression" -d $out/initrd"$extension" $out/initrd.img + # Compatibility symlink + ln -s "initrd.img" "$out/initrd" +else + ln -s "initrd" "$out/initrd$extension" fi