Files
disko/lib/types/btrfs.nix
2025-04-08 15:36:04 +00:00

297 lines
9.5 KiB
Nix

{
config,
options,
diskoLib,
lib,
rootMountPoint,
parent,
device,
...
}:
let
swapType = lib.mkOption {
type = lib.types.attrsOf (
lib.types.submodule (
{ name, ... }:
{
options = {
size = lib.mkOption {
type = lib.types.strMatching "^([0-9]+[KMGTP])?$";
description = "Size of the swap file (e.g. 2G)";
};
path = lib.mkOption {
type = lib.types.str;
default = name;
description = "Path to the swap file (relative to the mountpoint)";
};
priority = lib.mkOption {
type = lib.types.nullOr lib.types.int;
default = null;
description = ''
Specify the priority of the swap file. Priority is a value between 0 and 32767.
Higher numbers indicate higher priority.
null lets the kernel choose a priority, which will show up as a negative value.
'';
};
options = lib.mkOption {
type = lib.types.listOf lib.types.nonEmptyStr;
default = [ "defaults" ];
example = [ "nofail" ];
description = "Options used to mount the swap.";
};
};
}
)
);
default = { };
description = "Swap files";
};
swapConfig =
{ mountpoint, swap }:
{
swapDevices = builtins.map (file: {
device = "${mountpoint}/${file.path}";
inherit (file) priority options;
}) (lib.attrValues swap);
};
swapCreate =
mountpoint: swap:
lib.concatMapStringsSep "\n" (file: ''
if ! test -e "${mountpoint}/${file.path}"; then
btrfs filesystem mkswapfile --size ${file.size} "${mountpoint}/${file.path}"
fi
'') (lib.attrValues swap);
in
{
options = {
type = lib.mkOption {
type = lib.types.enum [ "btrfs" ];
internal = true;
description = "Type";
};
device = lib.mkOption {
type = lib.types.str;
default = device;
description = "Device to use";
};
extraArgs = lib.mkOption {
type = lib.types.listOf lib.types.str;
default = [ ];
description = "Extra arguments";
};
mountOptions = lib.mkOption {
type = lib.types.listOf lib.types.str;
default = [ "defaults" ];
description = "A list of options to pass to mount.";
};
subvolumes = lib.mkOption {
type = lib.types.attrsOf (
lib.types.submodule (
{ config, ... }:
{
options = {
name = lib.mkOption {
type = lib.types.str;
default = config._module.args.name;
description = "Name of the BTRFS subvolume.";
};
type = lib.mkOption {
type = lib.types.enum [ "btrfs_subvol" ];
default = "btrfs_subvol";
internal = true;
description = "Type";
};
extraArgs = lib.mkOption {
type = lib.types.listOf lib.types.str;
default = [ ];
description = "Extra arguments";
};
mountOptions = lib.mkOption {
type = lib.types.listOf lib.types.str;
default = [ "defaults" ];
description = "Options to pass to mount";
};
mountpoint = lib.mkOption {
type = lib.types.nullOr diskoLib.optionTypes.absolute-pathname;
default = null;
description = "Location to mount the subvolume to.";
};
swap = swapType;
};
}
)
);
default = { };
description = "Subvolumes to define for BTRFS.";
};
mountpoint = lib.mkOption {
type = lib.types.nullOr diskoLib.optionTypes.absolute-pathname;
default = null;
description = "A path to mount the BTRFS filesystem to.";
};
swap = swapType;
_parent = lib.mkOption {
internal = true;
default = parent;
};
_meta = lib.mkOption {
internal = true;
readOnly = true;
type = lib.types.functionTo diskoLib.jsonType;
default = _dev: { };
description = "Metadata";
};
_create = diskoLib.mkCreateOption {
inherit config options;
default = ''
# create the filesystem only if the device seems empty
if ! (blkid "${config.device}" -o export | grep -q '^TYPE='); then
mkfs.btrfs "${config.device}" ${toString config.extraArgs}
fi
${lib.optionalString (config.swap != { } || config.subvolumes != { }) ''
if (blkid "${config.device}" -o export | grep -q '^TYPE=btrfs$'); then
${lib.optionalString (config.swap != { }) ''
(
MNTPOINT=$(mktemp -d)
mount ${device} "$MNTPOINT" -o subvol=/
trap 'umount "$MNTPOINT"; rm -rf "$MNTPOINT"' EXIT
${swapCreate "$MNTPOINT" config.swap}
)
''}
${lib.concatMapStrings (subvol: ''
(
MNTPOINT=$(mktemp -d)
mount "${config.device}" "$MNTPOINT" -o subvol=/
trap 'umount "$MNTPOINT"; rm -rf "$MNTPOINT"' EXIT
SUBVOL_ABS_PATH="$MNTPOINT/${subvol.name}"
mkdir -p "$(dirname "$SUBVOL_ABS_PATH")"
if ! btrfs subvolume show "$SUBVOL_ABS_PATH" > /dev/null 2>&1; then
btrfs subvolume create "$SUBVOL_ABS_PATH" ${toString subvol.extraArgs}
fi
${swapCreate "$SUBVOL_ABS_PATH" subvol.swap}
)
'') (lib.attrValues config.subvolumes)}
fi
''}
'';
};
_mount = diskoLib.mkMountOption {
inherit config options;
default =
let
subvolMounts = lib.concatMapAttrs (
_: subvol:
lib.warnIf
(
subvol.mountOptions != (options.subvolumes.type.getSubOptions [ ]).mountOptions.default
&& subvol.mountpoint == null
)
"Subvolume ${subvol.name} has mountOptions but no mountpoint. See upgrade guide (2023-07-09 121df48)."
lib.optionalAttrs
(subvol.mountpoint != null)
{
${subvol.mountpoint} = ''
if ! findmnt "${config.device}" "${rootMountPoint}${subvol.mountpoint}" > /dev/null 2>&1; then
mount "${config.device}" "${rootMountPoint}${subvol.mountpoint}" \
${
lib.concatMapStringsSep " " (opt: "-o ${opt}") (subvol.mountOptions ++ [ "subvol=${subvol.name}" ])
} \
-o X-mount.mkdir
fi
'';
}
) config.subvolumes;
in
{
fs =
subvolMounts
// lib.optionalAttrs (config.mountpoint != null) {
${config.mountpoint} = ''
if ! findmnt "${config.device}" "${rootMountPoint}${config.mountpoint}" > /dev/null 2>&1; then
mount "${config.device}" "${rootMountPoint}${config.mountpoint}" \
${lib.concatMapStringsSep " " (opt: "-o ${opt}") config.mountOptions} \
-o X-mount.mkdir
fi
'';
};
};
};
_unmount = diskoLib.mkUnmountOption {
inherit config options;
default =
let
subvolMounts = lib.concatMapAttrs (
_: subvol:
lib.optionalAttrs (subvol.mountpoint != null) {
${subvol.mountpoint} = ''
if findmnt "${config.device}" "${rootMountPoint}${subvol.mountpoint}" > /dev/null 2>&1; then
umount "${rootMountPoint}${subvol.mountpoint}"
fi
'';
}
) config.subvolumes;
in
{
fs =
subvolMounts
// lib.optionalAttrs (config.mountpoint != null) {
${config.mountpoint} = ''
if findmnt "${config.device}" "${rootMountPoint}${config.mountpoint}" > /dev/null 2>&1; then
umount "${rootMountPoint}${config.mountpoint}"
fi
'';
};
};
};
_config = lib.mkOption {
internal = true;
readOnly = true;
default = [
(map (
subvol:
lib.optional (subvol.mountpoint != null) {
fileSystems.${subvol.mountpoint} = {
device = config.device;
fsType = "btrfs";
options = subvol.mountOptions ++ [ "subvol=${subvol.name}" ];
};
}
) (lib.attrValues config.subvolumes))
(lib.optional (config.mountpoint != null) {
fileSystems.${config.mountpoint} = {
device = config.device;
fsType = "btrfs";
options = config.mountOptions;
};
})
(map (
subvol:
swapConfig {
inherit (subvol) mountpoint swap;
}
) (lib.attrValues config.subvolumes))
(swapConfig {
inherit (config) mountpoint swap;
})
];
description = "NixOS configuration";
};
_pkgs = lib.mkOption {
internal = true;
readOnly = true;
type = lib.types.functionTo (lib.types.listOf lib.types.package);
default = pkgs: [
pkgs.btrfs-progs
pkgs.gnugrep
];
description = "Packages";
};
};
}