Moved everything into ./modules

1 files changed, 134 insertions, 0 deletions

diff --git a/modules/system/raid0.nix b/modules/system/raid0.nix
new file mode 100644
index 0000000..d260e29
--- /dev/null
+++ b/modules/system/raid0.nix
@@ -0,0 +1,134 @@
+{ config, pkgs, lib, ... }:
+
+with lib;
+with lib.types;
+with builtins;
+
+let
+  groups = filterAttrs (n: _: n != "_module") config.nixsap.system.lvm.raid0;
+
+  createLV = vg: lv: s: opts:
+    let
+      new = toString s;
+      stripes = toString opts.stripes;
+      sizeSpec = if opts.units == "%"
+                 then "--extents ${new}%VG"
+                 else "--size ${new}${opts.units}";
+      scale = {
+        "%" = "* 100 / $(vgs --unit b --noheadings --nosuffix --options vg_size ${vg})";
+        "M" = "/ ${toString (1000 * 1000)}";
+        "m" = "/ ${toString (1024 * 1024)}";
+        "G" = "/ ${toString (1000 * 1000 * 1000)}";
+        "g" = "/ ${toString (1024 * 1024 * 1024)}";
+        "T" = "/ ${toString (1000 * 1000 * 1000 * 1000)}";
+        "t" = "/ ${toString (1024 * 1024 * 1024 * 1024)}";
+      };
+    in pkgs.writeBashScript "raid0-create-${vg}-${lv}" ''
+      set -eu
+      device=/dev/${vg}/${lv}
+
+      lv_size=$(lvs --unit b --noheadings --nosuffix --options lv_size "$device" || echo 0)
+      old=$(( lv_size ${scale."${opts.units}"} ))
+
+      if (( ${new} == old )) ; then
+        exit 0
+      elif (( old == 0 )); then
+        lvcreate ${vg} --name ${lv} ${sizeSpec} --stripes ${stripes}
+      elif (( ${new} < old )) ; then
+        echo "Cannot shrink volume $device from $old ${opts.units} to ${new} ${opts.units}" >&2
+        exit 1
+      else
+        lvextend "$device" ${sizeSpec}
+        resize2fs "$device"
+      fi
+    '';
+
+  createVG = vg: pv: pkgs.writeBashScript "raid0-create-vg-${vg}" ''
+    set -eu
+    for pv in ${toString pv}; do
+      type=$(blkid -p -s TYPE -o value "$pv" || true)
+      if [ "$type" != LVM2_member ]; then
+        pvcreate "$pv"
+        if ! vgs ${vg}; then
+          vgcreate ${vg} "$pv"
+        else
+          vgextend ${vg} "$pv"
+        fi
+      fi
+    done
+  '';
+
+  mkRaidService = vg: opts:
+    let
+      ExecStart = pkgs.writeBashScript "raid0-${vg}" ''
+        set -eu
+        ${createVG vg opts.physical}
+        ${concatStringsSep "\n" (
+          mapAttrsToList (v: s:
+            "${createLV vg (baseNameOf v) s opts}")
+            opts.fileSystems
+         )}
+        vgchange -ay ${vg}
+        udevadm trigger --action=add
+      '';
+
+    in nameValuePair "raid0-${vg}" rec {
+      wantedBy = map (v: "dev-${vg}-${baseNameOf v}.device") (attrNames opts.fileSystems);
+      requires = map (pv: replaceStrings ["/"] ["-"] (removePrefix "/" pv) + ".device") opts.physical;
+      after = requires;
+      before = wantedBy;
+      unitConfig.DefaultDependencies = false;
+      path = with pkgs; [ utillinux lvm2 e2fsprogs ];
+      serviceConfig = {
+        inherit ExecStart;
+        RemainAfterExit = true;
+        Type = "oneshot";
+      };
+    };
+
+in {
+  options.nixsap.system = {
+    lvm.raid0 = mkOption {
+      description = "Set of LVM2 volume groups";
+      default = {};
+      type = attrsOf (submodule {
+        options = {
+          stripes = mkOption {
+            description = "Number of stripes";
+            type = int;
+            example = 2;
+          };
+          physical = mkOption {
+            description = "List of physical devices (must be even for stripes)";
+            example = [ "/dev/sdb" "/dev/sdc" ];
+            type = listOf path;
+          };
+          fileSystems = mkOption {
+            description = "Filesystems and their sizes";
+            type = attrsOf int;
+            example = { "/mariadb/db" = 100; };
+          };
+          units = mkOption {
+            description = "Units of size";
+            type = enum [ "%" "m" "g" "t"  "M" "G" "T"];
+          };
+        };
+      });
+    };
+  };
+
+  config = {
+    systemd.services = mapAttrs' mkRaidService groups;
+
+    fileSystems = foldl (a: b: a//b) {} (
+      mapAttrsToList (vg: opts: genAttrs (attrNames opts.fileSystems)
+        (fs: {
+          fsType = "ext4";
+          autoFormat = true;
+          device = "/dev/${vg}/${baseNameOf fs}";
+        })
+      ) groups
+    );
+  };
+}
+