qemu-vm: use nixos module patterns for filesystems

This commit is contained in:
Linus Heckemann 2022-12-20 20:35:40 +01:00
parent bf41254a8a
commit 246d09fea2

View file

@ -1006,20 +1006,21 @@ in
}) cfg.emptyDiskImages)
];
fileSystems = mkVMOverride cfg.fileSystems;
# Mount the host filesystem via 9P, and bind-mount the Nix store
# of the host into our own filesystem. We use mkVMOverride to
# allow this module to be applied to "normal" NixOS system
# configuration, where the regular value for the `fileSystems'
# attribute should be disregarded for the purpose of building a VM
# test image (since those filesystems don't exist in the VM).
fileSystems =
let
virtualisation.fileSystems = let
mkSharedDir = tag: share:
{
name =
if tag == "nix-store" && cfg.writableStore
then "/nix/.ro-store"
else share.target;
then "/nix/.ro-store"
else share.target;
value.device = tag;
value.fsType = "9p";
value.neededForBoot = true;
@ -1027,48 +1028,42 @@ in
[ "trans=virtio" "version=9p2000.L" "msize=${toString cfg.msize}" ]
++ lib.optional (tag == "nix-store") "cache=loose";
};
in
mkVMOverride (cfg.fileSystems //
optionalAttrs cfg.useDefaultFilesystems {
"/".device = cfg.bootDevice;
"/".fsType = "ext4";
"/".autoFormat = true;
} //
optionalAttrs (cfg.diskImage == null) {
"/".device = "tmpfs";
"/".fsType = "tmpfs";
} //
optionalAttrs config.boot.tmpOnTmpfs {
"/tmp" = {
in lib.mkMerge [
(lib.mapAttrs' mkSharedDir cfg.sharedDirectories)
{
"/" = lib.mkIf cfg.useDefaultFilesystems (if cfg.diskImage == null then {
device = "tmpfs";
fsType = "tmpfs";
} else {
device = cfg.bootDevice;
fsType = "ext4";
autoFormat = true;
});
"/tmp" = lib.mkIf config.boot.tmpOnTmpfs {
device = "tmpfs";
fsType = "tmpfs";
neededForBoot = true;
# Sync with systemd's tmp.mount;
options = [ "mode=1777" "strictatime" "nosuid" "nodev" "size=${toString config.boot.tmpOnTmpfsSize}" ];
};
} //
optionalAttrs cfg.useNixStoreImage {
"/nix/${if cfg.writableStore then ".ro-store" else "store"}" = {
"/nix/${if cfg.writableStore then ".ro-store" else "store"}" = lib.mkIf cfg.useNixStoreImage {
device = "${lookupDriveDeviceName "nix-store" cfg.qemu.drives}";
neededForBoot = true;
options = [ "ro" ];
};
} //
optionalAttrs (cfg.writableStore && cfg.writableStoreUseTmpfs) {
"/nix/.rw-store" = {
"/nix/.rw-store" = lib.mkIf (cfg.writableStore && cfg.writableStoreUseTmpfs) {
fsType = "tmpfs";
options = [ "mode=0755" ];
neededForBoot = true;
};
} //
optionalAttrs cfg.useBootLoader {
# see note [Disk layout with `useBootLoader`]
"/boot" = {
"/boot" = lib.mkIf cfg.useBootLoader {
device = "${lookupDriveDeviceName "boot" cfg.qemu.drives}2"; # 2 for e.g. `vdb2`, as created in `bootDisk`
fsType = "vfat";
noCheck = true; # fsck fails on a r/o filesystem
};
} // lib.mapAttrs' mkSharedDir cfg.sharedDirectories);
}
];
boot.initrd.systemd = lib.mkIf (config.boot.initrd.systemd.enable && cfg.writableStore) {
mounts = [{