dotfiles.nix/nixos/common/optional/ephemeral-btrfs.nix
2024-08-08 09:02:42 +08:00

64 lines
1.5 KiB
Nix

{
lib,
config,
...
}: let
hostname = config.networking.hostName;
in {
imports = [
./persist.nix
];
boot.initrd.postDeviceCommands = lib.mkAfter ''
mkdir /btrfs_tmp
mount /dev/nvme0n1p2 /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
'';
fileSystems = {
"/" = {
device = "/dev/disk/by-label/${hostname}";
fsType = "btrfs";
options = ["subvol=root" "compress=zstd"];
};
"/nix" = {
device = "/dev/disk/by-label/${hostname}";
fsType = "btrfs";
options = ["subvol=nix" "compress=zstd"];
};
"/persist" = {
device = "/dev/disk/by-label/${hostname}";
fsType = "btrfs";
options = ["subvol=persist" "compress=zstd"];
neededForBoot = true;
};
"/swap" = {
device = "/dev/disk/by-label/${hostname}";
fsType = "btrfs";
options = ["subvol=swap" "compress=zstd"];
};
};
}