xen: move to by-name

Signed-off-by: Fernando Rodrigues <alpha@sigmasquadron.net>
Co-authored-by: Yaroslav Bolyukin <iam@lach.pw>
Co-authored-by: Emily <vcs@emily.moe>

pkgs/applications/virtualization/xen/4.18/default.nix

@@ -1,56 +0,0 @@
-{
-  lib,
-  fetchpatch,
-  callPackage,
-  ocaml-ng,
-  ...
-}@genericDefinition:
-
-let
-  upstreamPatches = import ../generic/patches.nix {
-    inherit lib;
-    inherit fetchpatch;
-  };
-
-  upstreamPatchList = lib.lists.flatten (
-    with upstreamPatches;
-    [
-      QUBES_REPRODUCIBLE_BUILDS
-      XSA_462
-    ]
-  );
-in
-
-callPackage (import ../generic/default.nix {
-  pname = "xen";
-  branch = "4.18";
-  version = "4.18.3";
-  latest = false;
-  pkg = {
-    xen = {
-      rev = "bd51e573a730efc569646379cd59ccba967cde97";
-      hash = "sha256-OFiFdpPCXR+sWjzFHCORtY4DkWyggvxkcsGdgEyO1ts=";
-      patches = [ ] ++ upstreamPatchList;
-    };
-    qemu = {
-      rev = "0df9387c8983e1b1e72d8c574356f572342c03e6";
-      hash = "sha256-BX+LXfNzwdUMALwwI1ZDW12dJ357oynjnrboLHREDGQ=";
-      patches = [ ];
-    };
-    seaBIOS = {
-      rev = "ea1b7a0733906b8425d948ae94fba63c32b1d425";
-      hash = "sha256-J2FuT+FXn9YoFLSfxDOxyKZvKrys59a6bP1eYvEXVNU=";
-      patches = [ ];
-    };
-    ovmf = {
-      rev = "ba91d0292e593df8528b66f99c1b0b14fadc8e16";
-      hash = "sha256-htOvV43Hw5K05g0SF3po69HncLyma3BtgpqYSdzRG4s=";
-      patches = [ ];
-    };
-    ipxe = {
-      rev = "1d1cf74a5e58811822bee4b3da3cff7282fcdfca";
-      hash = "sha256-8pwoPrmkpL6jIM+Y/C0xSvyrBM/Uv0D1GuBwNm+0DHU=";
-      patches = [ ];
-    };
-  };
-}) ({ ocamlPackages = ocaml-ng.ocamlPackages_4_14; } // genericDefinition)

pkgs/applications/virtualization/xen/4.19/default.nix

@@ -1,58 +0,0 @@
-{
-  lib,
-  fetchpatch,
-  callPackage,
-  ocaml-ng,
-  ...
-}@genericDefinition:
-
-let
-  upstreamPatches = import ../generic/patches.nix {
-    inherit lib;
-    inherit fetchpatch;
-  };
-
-  upstreamPatchList = lib.lists.flatten (
-    with upstreamPatches;
-    [
-      QUBES_REPRODUCIBLE_BUILDS
-      XSA_460
-      XSA_461
-      XSA_462
-    ]
-  );
-in
-
-callPackage (import ../generic/default.nix {
-  pname = "xen";
-  branch = "4.19";
-  version = "4.19.0";
-  latest = true;
-  pkg = {
-    xen = {
-      rev = "026c9fa29716b0ff0f8b7c687908e71ba29cf239";
-      hash = "sha256-Q6x+2fZ4ITBz6sKICI0NHGx773Rc919cl+wzI89UY+Q=";
-      patches = [ ] ++ upstreamPatchList;
-    };
-    qemu = {
-      rev = "0df9387c8983e1b1e72d8c574356f572342c03e6";
-      hash = "sha256-BX+LXfNzwdUMALwwI1ZDW12dJ357oynjnrboLHREDGQ=";
-      patches = [ ];
-    };
-    seaBIOS = {
-      rev = "a6ed6b701f0a57db0569ab98b0661c12a6ec3ff8";
-      hash = "sha256-hWemj83cxdY8p+Jhkh5GcPvI0Sy5aKYZJCsKDjHTUUk=";
-      patches = [ ];
-    };
-    ovmf = {
-      rev = "ba91d0292e593df8528b66f99c1b0b14fadc8e16";
-      hash = "sha256-htOvV43Hw5K05g0SF3po69HncLyma3BtgpqYSdzRG4s=";
-      patches = [ ];
-    };
-    ipxe = {
-      rev = "1d1cf74a5e58811822bee4b3da3cff7282fcdfca";
-      hash = "sha256-8pwoPrmkpL6jIM+Y/C0xSvyrBM/Uv0D1GuBwNm+0DHU=";
-      patches = [ ];
-    };
-  };
-}) ({ ocamlPackages = ocaml-ng.ocamlPackages_4_14; } // genericDefinition)

pkgs/applications/virtualization/xen/packages.nix

@@ -1,71 +0,0 @@
-{
-  python3Packages,
-  python311Packages,
-  callPackage,
-}:
-let
-  standard = {
-    # Broken with python 3.12+ when using internal QEMU due to https://github.com/NixOS/nixpkgs/issues/253751
-    python3Packages = python311Packages;
-    meta = {
-      description = "Standard";
-      longDescription = ''
-        Standard version of the Xen Project Hypervisor. Uses forks of QEMU, SeaBIOS,
-        OVMF and iPXE provided by the Xen Project. This provides the vanilla Xen
-        experience, but wastes space and build time. A typical NixOS setup that runs
-        lots of VMs will usually need to build two different versions of QEMU when using
-        this Xen derivation (one fork and upstream).
-      '';
-    };
-  };
-  slim = {
-    inherit python3Packages;
-    meta = {
-      description = "Without Internal Components";
-      longDescription = ''
-        Slimmed-down version of the Xen Project Hypervisor that reuses nixpkgs packages
-        as much as possible. Instead of using the Xen Project forks for various internal
-        components, this version uses `seabios`, `ovmf` and `ipxe` from Nixpkgs. These
-        components may ocasionally get out of sync with the hypervisor itself, but this
-        builds faster and uses less space than the default derivation.
-      '';
-    };
-  };
-in
-# TODO: generalise this to automatically generate both Xen variants for each ./<version>/default.nix.
-rec {
-  xen_4_19 = callPackage ./4.19/default.nix {
-    inherit (standard) meta python3Packages;
-  };
-  xen_4_19-slim = xen_4_19.override {
-    withInternalQEMU = false;
-    withInternalSeaBIOS = false;
-    withInternalOVMF = false;
-    withInternalIPXE = false;
-    inherit (slim) meta python3Packages;
-  };
-
-  xen_4_18 = callPackage ./4.18/default.nix {
-    inherit (standard) meta python3Packages;
-  };
-  xen_4_18-slim = xen_4_18.override {
-    withInternalQEMU = false;
-    withInternalSeaBIOS = false;
-    withInternalOVMF = false;
-    withInternalIPXE = false;
-    inherit (slim) meta python3Packages;
-  };
-
-  xen_4_17 = callPackage ./4.17/default.nix {
-    inherit (standard) meta python3Packages;
-  };
-  xen_4_17-slim = xen_4_17.override {
-    withInternalQEMU = false;
-    withInternalSeaBIOS = false;
-    withInternalOVMF = false;
-    withInternalIPXE = false;
-    inherit (slim) meta;
-    # Broken with python 3.12+ due to distutils missing.
-    python3Packages = python311Packages;
-  };
-}

pkgs/by-name/xe/xen/README.md

@@ -17,7 +17,7 @@
 
 # Xen Project Hypervisor <a href="https://xenproject.org/"><img src="https://downloads.xenproject.org/Branding/Mascots/Xen-Fu-Panda-2000px.png" width="48px" align="top" alt="Xen Fu Panda"></a>
 
-This directory includes the build recipes for the [Xen Project Hypervisor](https://xenproject.org/).
+This directory begins the [Xen Project Hypervisor](https://xenproject.org/) build process.
 
 Some other notable packages that compose the Xen Project Ecosystem include:
 
@@ -32,81 +32,56 @@ Some other notable packages that compose the Xen Project Ecosystem include:
 
 ### Manually
 
-1. Create one directory per branch.
+1. [Update](https://xenbits.xenproject.org/gitweb/) the `package.nix` file for
-1. [Update](https://xenbits.xenproject.org/gitweb/) the `default.nix` files for
+   the latest branch of Xen.
-   the branches that already exist and copy a new one to any branches that do
+   - Do not forget to set the `branch`, `version`, and `latest` attributes.
-   not yet exist in Nixpkgs.
-   - Do not forget to set the `branch`, `version`, and `latest` attributes for
-     each of the `default.nix` files.
    - The revisions are preferably commit hashes, but tag names are acceptable
      as well.
-1. Make sure all branches build. (Both the `standard` and `slim` versions)
+1. Make sure it builds.
-1. Use the NixOS module to test if dom0 boots successfully on all new versions.
+1. Use the NixOS module to test if dom0 boots successfully on the new version.
 1. Make sure the `meta` attributes evaluate to something that makes sense. The
    following one-line command is useful for testing this:
 
    ```console
-   xenToEvaluate=xen; echo -e "\033[1m$(nix eval .#"$xenToEvaluate".meta.description --raw 2> /dev/null)\033[0m\n\n$(nix eval .#"$xenToEvaluate".meta.longDescription --raw 2> /dev/null)"
+   echo -e "\033[1m$(nix eval .#xen.meta.description --raw 2> /dev/null)\033[0m\n\n$(nix eval .#xen.meta.longDescription --raw 2> /dev/null)"
    ```
 
-   Change the value of `xenToEvaluate` to evaluate all relevant Xen packages.
 1. Run `xtf --all --host` as root when booted into the Xen update, and make
-   sure no tests fail.
+   sure no important tests fail.
 1. Clean up your changes and commit them, making sure to follow the
    [Nixpkgs Contribution Guidelines](../../../../CONTRIBUTING.md).
 1. Open a PR and await a review from the current maintainers.
 
 ## Features
 
-### Pre-fetched Sources
+### Generic Builder
 
-On a typical Xen build, the Xen Makefiles will fetch more required sources with
+`buildXenPackage` is a helpful utility capable of building Xen when passed
-`git` and `wget`. Due to the Nix Sandbox, build-time fetching will fail, so we
+certain attributes. The `package.nix` file on this directory includes all
-pre-fetch the required sources before building.[^1] To accomplish this, we have
+important attributes for building a Xen package with Nix. Downstreams can
-a `prefetchedSources` attribute that contains the required derivations, if they
+pin their Xen revision or include extra patches if the default Xen package
-are requested by the main Xen build.
+does not meet their needs.
 
 ### EFI
 
 Building `xen.efi` requires an `ld` with PE support.[^2]
 
 We use a `makeFlag` to override the `$LD` environment variable to point to our
-patched `efiBinutils`. For more information, see the comment in `./generic/default.nix`.
+patched `efiBinutils`. For more information, see the comment in `pkgs/build-support/xen/default.nix`.
 
 > [!TIP]
 > If you are certain you will not be running Xen in an x86 EFI environment, disable
 the `withEFI` flag with an [override](https://nixos.org/manual/nixpkgs/stable/#chap-overrides)
 to save you the need to compile `efiBinutils`.
 
-### Default Overrides
-
-By default, Xen also builds
-[QEMU](https://www.qemu.org/),
-[SeaBIOS](https://www.seabios.org/SeaBIOS),
-[OVMF](https://github.com/tianocore/tianocore.github.io/wiki/OVMF) and
-[iPXE](https://ipxe.org/).
-
-- QEMU is used for stubdomains and handling devices.
-- SeaBIOS is the default legacy BIOS ROM for HVM domains.
-- OVMF is the default UEFI ROM for HVM domains.
-- iPXE provides a PXE boot environment for HVMs.
-
-However, those packages are already available on Nixpkgs, and Xen does not
-necessarily need to build them into the main hypervisor build. For this reason,
-we also have the `withInternal<Component>` flags, which enables and disables
-building those built-in components. The two most popular Xen configurations will
-be the default build, with all built-in components, and a `slim` build, with none
-of those components. To simplify this process, the `./packages.nix` file includes
-the `xen-slim` package overrides that have all `withInternal<Component>` flags
-disabled. See the `meta.longDescription` attribute for the `xen-slim` packages
-for more information.
-
 ## Security
 
-We aim to support all **security-supported** versions of Xen at any given time.
+We aim to support the **latest** version of Xen at any given time.
 See the [Xen Support Matrix](https://xenbits.xen.org/docs/unstable/support-matrix.html)
-for a list of versions. As soon as a version is no longer **security-supported**,
+for a list of versions. As soon as a version is no longer the newest, it should
-it should be removed from Nixpkgs.
+be removed from Nixpkgs (`master`). If you need earlier versions of Xen, consider
+building your own Xen by following the instructions in the **Generic Builder**
+section.
 
 > [!CAUTION]
 > Pull requests that introduce XSA patches

pkgs/by-name/xe/xen/package.nix

@@ -0,0 +1,11 @@
+{
+  buildXenPackage,
+  python3Packages,
+}:
+
+buildXenPackage.override { inherit python3Packages; } {
+  pname = "xen";
+  version = "4.19.0";
+  rev = "026c9fa29716b0ff0f8b7c687908e71ba29cf239";
+  hash = "sha256-Q6x+2fZ4ITBz6sKICI0NHGx773Rc919cl+wzI89UY+Q=";
+}

pkgs/top-level/all-packages.nix

@@ -26413,10 +26413,9 @@ with pkgs;
     glusterfsSupport = lib.meta.availableOn stdenv.hostPlatform glusterfs && lib.meta.availableOn stdenv.hostPlatform libuuid;
   });
 
-  # See `xenPackages` source for explanations.
   # Building with `xen` instead of `xen-slim` is possible, but makes no sense.
-  qemu_xen_4_19 = lowPrio (qemu.override { hostCpuTargets = [ "i386-softmmu" ]; xenSupport = true; xen = xenPackages.xen_4_19-slim; });
+  qemu_xen_4_19 = lowPrio (qemu.override { hostCpuTargets = [ "i386-softmmu" ]; xenSupport = true; xen = xen_4_19-slim; });
-  qemu_xen_4_18 = lowPrio (qemu.override { hostCpuTargets = [ "i386-softmmu" ]; xenSupport = true; xen = xenPackages.xen_4_18-slim; });
+  qemu_xen_4_18 = lowPrio (qemu.override { hostCpuTargets = [ "i386-softmmu" ]; xenSupport = true; xen = xen_4_18-slim; });
   qemu_xen = qemu_xen_4_19;
 
   qemu_test = lowPrio (qemu.override { hostCpuOnly = true; nixosTestRunner = true; });
@@ -33848,10 +33847,6 @@ with pkgs;
 
   xdotool = callPackage ../tools/X11/xdotool { };
 
-  xenPackages = recurseIntoAttrs (callPackage ../applications/virtualization/xen/packages.nix {});
-
-  xen = xenPackages.xen_4_19;
-  xen-slim = xenPackages.xen_4_19-slim;
   buildXenPackage = callPackage ../build-support/xen { };
 
   xkbset = callPackage ../tools/X11/xkbset { };