From 13fad0f81b2bd50fd421bd5856a35f1f7c032257 Mon Sep 17 00:00:00 2001 From: Luke Granger-Brown Date: Sun, 3 Jan 2021 18:29:34 +0000 Subject: [PATCH] nixos/systemd-boot: create boot entries for specialisations Some specialisations (such as those which affect various boot-time attributes) cannot be switched to at runtime. This allows picking the specialisation at boot time. --- .../systemd-boot/systemd-boot-builder.py | 73 +++++++++++++------ nixos/tests/systemd-boot.nix | 23 ++++++ 2 files changed, 73 insertions(+), 23 deletions(-) diff --git a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py index 6c26b4e0f87a..c38bef9d6d4b 100644 --- a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py +++ b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py @@ -17,19 +17,28 @@ import glob import os.path from typing import Tuple, List, Optional +SystemIdentifier = Tuple[Optional[str], int, Optional[str]] + def copy_if_not_exists(source: str, dest: str) -> None: if not os.path.exists(dest): shutil.copyfile(source, dest) -def system_dir(profile: Optional[str], generation: int) -> str: +def generation_dir(profile: Optional[str], generation: int) -> str: if profile: return "/nix/var/nix/profiles/system-profiles/%s-%d-link" % (profile, generation) else: return "/nix/var/nix/profiles/system-%d-link" % (generation) -BOOT_ENTRY = """title NixOS{profile} +def system_dir(profile: Optional[str], generation: int, specialisation: Optional[str]) -> str: + d = generation_dir(profile, generation) + if specialisation: + return os.path.join(d, "specialisation", specialisation) + else: + return d + +BOOT_ENTRY = """title NixOS{profile}{specialisation} version Generation {generation} {description} linux {kernel} initrd {initrd} @@ -46,26 +55,34 @@ efi /efi/memtest86/BOOTX64.efi """ -def write_loader_conf(profile: Optional[str], generation: int) -> None: +def generation_conf_filename(profile: Optional[str], generation: int, specialisation: Optional[str]) -> str: + pieces = [ + "nixos", + profile or None, + "generation", + str(generation), + f"specialisation-{specialisation}" if specialisation else None, + ] + return "-".join(p for p in pieces if p) + ".conf" + + +def write_loader_conf(profile: Optional[str], generation: int, specialisation: Optional[str]) -> None: with open("@efiSysMountPoint@/loader/loader.conf.tmp", 'w') as f: if "@timeout@" != "": f.write("timeout @timeout@\n") - if profile: - f.write("default nixos-%s-generation-%d.conf\n" % (profile, generation)) - else: - f.write("default nixos-generation-%d.conf\n" % (generation)) + f.write("default %s\n" % generation_conf_filename(profile, generation, specialisation)) if not @editor@: f.write("editor 0\n"); f.write("console-mode @consoleMode@\n"); os.rename("@efiSysMountPoint@/loader/loader.conf.tmp", "@efiSysMountPoint@/loader/loader.conf") -def profile_path(profile: Optional[str], generation: int, name: str) -> str: - return os.path.realpath("%s/%s" % (system_dir(profile, generation), name)) +def profile_path(profile: Optional[str], generation: int, specialisation: Optional[str], name: str) -> str: + return os.path.realpath("%s/%s" % (system_dir(profile, generation, specialisation), name)) -def copy_from_profile(profile: Optional[str], generation: int, name: str, dry_run: bool = False) -> str: - store_file_path = profile_path(profile, generation, name) +def copy_from_profile(profile: Optional[str], generation: int, specialisation: Optional[str], name: str, dry_run: bool = False) -> str: + store_file_path = profile_path(profile, generation, specialisation, name) suffix = os.path.basename(store_file_path) store_dir = os.path.basename(os.path.dirname(store_file_path)) efi_file_path = "/efi/nixos/%s-%s.efi" % (store_dir, suffix) @@ -95,19 +112,17 @@ def describe_generation(generation_dir: str) -> str: return description -def write_entry(profile: Optional[str], generation: int, machine_id: str) -> None: - kernel = copy_from_profile(profile, generation, "kernel") - initrd = copy_from_profile(profile, generation, "initrd") +def write_entry(profile: Optional[str], generation: int, specialisation: Optional[str], machine_id: str) -> None: + kernel = copy_from_profile(profile, generation, specialisation, "kernel") + initrd = copy_from_profile(profile, generation, specialisation, "initrd") try: - append_initrd_secrets = profile_path(profile, generation, "append-initrd-secrets") + append_initrd_secrets = profile_path(profile, generation, specialisation, "append-initrd-secrets") subprocess.check_call([append_initrd_secrets, "@efiSysMountPoint@%s" % (initrd)]) except FileNotFoundError: pass - if profile: - entry_file = "@efiSysMountPoint@/loader/entries/nixos-%s-generation-%d.conf" % (profile, generation) - else: - entry_file = "@efiSysMountPoint@/loader/entries/nixos-generation-%d.conf" % (generation) - generation_dir = os.readlink(system_dir(profile, generation)) + entry_file = "@efiSysMountPoint@/loader/entries/%s" % ( + generation_conf_filename(profile, generation, specialisation)) + generation_dir = os.readlink(system_dir(profile, generation, specialisation)) tmp_path = "%s.tmp" % (entry_file) kernel_params = "init=%s/init " % generation_dir @@ -115,6 +130,7 @@ def write_entry(profile: Optional[str], generation: int, machine_id: str) -> Non kernel_params = kernel_params + params_file.read() with open(tmp_path, 'w') as f: f.write(BOOT_ENTRY.format(profile=" [" + profile + "]" if profile else "", + specialisation=" (%s)" % specialisation if specialisation else "", generation=generation, kernel=kernel, initrd=initrd, @@ -133,7 +149,7 @@ def mkdir_p(path: str) -> None: raise -def get_generations(profile: Optional[str] = None) -> List[Tuple[Optional[str], int]]: +def get_generations(profile: Optional[str] = None) -> List[SystemIdentifier]: gen_list = subprocess.check_output([ "@nix@/bin/nix-env", "--list-generations", @@ -145,10 +161,19 @@ def get_generations(profile: Optional[str] = None) -> List[Tuple[Optional[str], gen_lines.pop() configurationLimit = @configurationLimit@ - return [ (profile, int(line.split()[0])) for line in gen_lines ][-configurationLimit:] + configurations: List[SystemIdentifier] = [ (profile, int(line.split()[0]), None) for line in gen_lines ] + return configurations[-configurationLimit:] -def remove_old_entries(gens: List[Tuple[Optional[str], int]]) -> None: +def get_specialisations(profile: Optional[str], generation: int, _: Optional[str]) -> List[SystemIdentifier]: + specialisations_dir = os.path.join( + system_dir(profile, generation, None), "specialisation") + if not os.path.exists(specialisations_dir): + return [] + return [(profile, generation, spec) for spec in os.listdir(specialisations_dir)] + + +def remove_old_entries(gens: List[SystemIdentifier]) -> None: rex_profile = re.compile("^@efiSysMountPoint@/loader/entries/nixos-(.*)-generation-.*\.conf$") rex_generation = re.compile("^@efiSysMountPoint@/loader/entries/nixos.*-generation-(.*)\.conf$") known_paths = [] @@ -243,6 +268,8 @@ def main() -> None: for gen in gens: try: write_entry(*gen, machine_id) + for specialisation in get_specialisations(*gen): + write_entry(*specialisation, machine_id) if os.readlink(system_dir(*gen)) == args.default_config: write_loader_conf(*gen) except OSError as e: diff --git a/nixos/tests/systemd-boot.nix b/nixos/tests/systemd-boot.nix index 3c93cb82d646..ae3727afaf69 100644 --- a/nixos/tests/systemd-boot.nix +++ b/nixos/tests/systemd-boot.nix @@ -39,6 +39,29 @@ in ''; }; + # Check that specialisations create corresponding boot entries. + specialisation = makeTest { + name = "systemd-boot-specialisation"; + meta.maintainers = with pkgs.stdenv.lib.maintainers; [ lukegb ]; + + machine = { pkgs, lib, ... }: { + imports = [ common ]; + specialisation.something.configuration = {}; + }; + + testScript = '' + machine.start() + machine.wait_for_unit("multi-user.target") + + machine.succeed( + "test -e /boot/loader/entries/nixos-generation-1-specialisation-something.conf" + ) + machine.succeed( + "grep -q 'title NixOS (something)' /boot/loader/entries/nixos-generation-1-specialisation-something.conf" + ) + ''; + }; + # Boot without having created an EFI entry--instead using default "/EFI/BOOT/BOOTX64.EFI" fallback = makeTest { name = "systemd-boot-fallback";