nixos-config/disko/impermanence-btrfs.nix

97 lines
2.4 KiB
Nix

{device ? throw "Set this to your disk device, e.g. /dev/sda", ...}: {
disko.devices = {
disk.main = {
inherit device;
type = "disk";
content = {
type = "gpt";
partitions = {
boot = {
name = "boot";
size = "1M";
type = "EF02";
};
esp = {
name = "ESP";
size = "500M";
type = "EF00";
content = {
type = "filesystem";
format = "vfat";
mountpoint = "/boot";
};
};
swap = {
size = "32G";
content = {
type = "swap";
resumeDevice = true;
};
};
root = {
name = "root";
size = "100%";
content = {
type = "lvm_pv";
vg = "root_vg";
};
};
};
};
};
lvm_vg = {
root_vg = {
type = "lvm_vg";
lvs = {
root = {
size = "100%FREE";
content = {
type = "btrfs";
extraArgs = ["-f"];
subvolumes = {
"/root" = {
mountpoint = "/";
};
"/persist" = {
mountOptions = ["subvol=persist" "noatime"];
mountpoint = "/persist";
};
"/nix" = {
mountOptions = ["subvol=nix" "noatime"];
mountpoint = "/nix";
};
};
};
};
};
};
};
};
boot.initrd.postDeviceCommands = ''
mkdir -p /btrfs_tmp
mount /dev/root_vg/root /btrfs_tmp
if [[ -e /btrfs_tmp/root ]]; then
mkdir -p /btrfs_tmp/old_roots
timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/root)" "+%Y-%m-%-d_%H:%M:%S")
mv /btrfs_tmp/root "/btrfs_tmp/old_roots/$timestamp"
fi
delete_subvolume_recursively() {
IFS=$'\n'
for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
delete_subvolume_recursively "/btrfs_tmp/$i"
done
btrfs subvolume delete "$1"
}
for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do
delete_subvolume_recursively "$i"
done
btrfs subvolume create /btrfs_tmp/root
umount /btrfs_tmp
'';
}