Re: ZFS on Guix

[raid5atemyhomework <raid5atemyhomework@protonmail.com>]

Hi Carlo,

Thanks, I modified patch as below.

I also can't get `guix system vm` to run in my hacking env, so I couldn't make a VM for testing like you did.  I got this:

```
Formatting '/gnu/store/imdlq0cay61d2cw3199g04z9bp16qx8j-qemu-image', fmt=qcow2 cluster_size=65536 compression_type=zlib size=73400320 lazy_refcounts=off refcount_bits=16
Could not access KVM kernel module: Permission denied
qemu-system-x86_64: failed to initialize kvm: Permission denied
```

Any tips on getting `guix system vm` working?  I've never used VMs before.  My dev env is a foreign distro with Guix installed on top.

The above issue also means I haven't actually run the tests I made in `gnu/tests/linux-modules.scm`, because it requires building a VM as well.

However, I *did* do a bunch of `guix system build` tests:

* With the same `configuration.scm` that uses the legacy `(kernel-loadable-modules ...)` declaration in `operating-system`, I tried both with and without the patch.
  * Without patch and with patch created builds with a different hash, however, they linked to the same directories. `diff -r` did not find any differences.
* With the patch, I made two variants of `configuration.scm`, one that used the legacy `(kernel-loadable-modules...)` and another that used a service that extended `kernel-laodable-module-service-type`.
  * Builds resulted in the exact same system with exact same hash.



From 4beb73c62995cf236b402dad8e1c36016027c781 Mon Sep 17 00:00:00 2001
From: raid5atemyhomework <raid5atemyhomework@protonmail.com>
Date: Tue, 5 Jan 2021 22:27:56 +0800
Subject: [PATCH] gnu: Allow services to install kernel-loadable modules.

* gnu/system.scm (operating-system-directory-base-entries): Remove code
to handle generation of "kernel" and "hurd".
(operating-system-default-essential-services): Instantiate
kernel-loadable-module-service.
(hurd-default-essential-services): Instantiate
kernel-loadable-module-service.
(package-for-kernel): Move ...
* gnu/services.scm: ... to here.
(kernel-loadable-module-service-type): New variable.
(kernel-loadable-module-service): New procedure.
* gnu/tests/linux-modules.scm (run-loadable-kernel-modules-test): Move
code to ...
(run-loadable-kernel-modules-test-base): ... new procedure here.
(run-loadable-kernel-modules-service-test): New procedure.
(%test-loadable-kernel-modules-service-0): New variable.
(%test-loadable-kernel-modules-service-1): New variable.
(%test-loadable-kernel-modules-service-2): New variable.
* doc/guix.texi: Document kernel-loadable-module-service-type.
---
 doc/guix.texi               |  6 +++
 gnu/services.scm            | 70 ++++++++++++++++++++++++++++++++
 gnu/system.scm              | 37 +++++------------
 gnu/tests/linux-modules.scm | 81 ++++++++++++++++++++++++++++++++-----
 4 files changed, 157 insertions(+), 37 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 0f6e95a65a..78770151e3 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -32409,6 +32409,12 @@ configuration when you use @command{guix system reconfigure},
 @command{guix system init}, or @command{guix deploy}.
 @end defvr

+@defvr {Scheme Variable} kernel-loadable-module-service-type
+Type of the service that collects lists of packages containing
+kernel-loadable modules, and adds them to the set of kernel-loadable
+modules.
+@end defvr
+
 @node Shepherd Services
 @subsection Shepherd Services

diff --git a/gnu/services.scm b/gnu/services.scm
index 13259dfaee..d7332a46b2 100644
--- a/gnu/services.scm
+++ b/gnu/services.scm
@@ -2,6 +2,7 @@
 ;;; Copyright © 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2016 Chris Marusich <cmmarusich@gmail.com>
 ;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -33,6 +34,8 @@
   #:use-module (guix diagnostics)
   #:autoload   (guix openpgp) (openpgp-format-fingerprint)
   #:use-module (guix modules)
+  #:use-module (guix packages)
+  #:use-module (guix utils)
   #:use-module (gnu packages base)
   #:use-module (gnu packages bash)
   #:use-module (gnu packages hurd)
@@ -75,6 +78,7 @@
             service-back-edges
             instantiate-missing-services
             fold-services
+            kernel-loadable-module-service

             service-error?
             missing-value-service-error?
@@ -106,6 +110,7 @@
             profile-service-type
             firmware-service-type
             gc-root-service-type
+            kernel-loadable-module-service-type

             %boot-service
             %activation-service
@@ -864,6 +869,71 @@ as Wifi cards.")))
 will not be reclaimed by the garbage collector.")
                 (default-value '())))

+;; Configuration for the kernel builder.
+(define-record-type* <kernel-builder-configuration> kernel-builder-configuration
+  make-kernel-builder-configuration
+  kernel-builder-configuration?
+  this-kernel-builder-configuration
+
+  (kernel   kernel-builder-configuration-kernel   (default #f))
+  (hurd     kernel-builder-configuration-hurd     (default #f))
+  (modules  kernel-builder-configuration-modules  (default '())))
+
+(define (package-for-kernel target-kernel module-package)
+  "Return a package like MODULE-PACKAGE, adapted for TARGET-KERNEL, if
+possible (that is if there's a LINUX keyword argument in the build system)."
+  (package
+    (inherit module-package)
+    (arguments
+     (substitute-keyword-arguments (package-arguments module-package)
+       ((#:linux kernel #f)
+        target-kernel)))))
+
+(define (kernel-builder-configuration->system-entry config)
+  "Return the kernel and hurd entries of the 'system' directory."
+  (mbegin %store-monad
+    (let* ((kernel  (kernel-builder-configuration-kernel config))
+           (hurd    (kernel-builder-configuration-hurd config))
+           (modules (kernel-builder-configuration-modules config))
+           (kernel  (if hurd
+                        kernel
+                        (profile
+                         (content (packages->manifest
+                                   (cons kernel
+                                         (map (lambda (module)
+                                                (if (package? module)
+                                                    (package-for-kernel kernel module)
+                                                    module))
+                                              modules))))
+                         (hooks (list linux-module-database))))))
+      (return `(("kernel" ,kernel)
+                ,@(if hurd `(("hurd" ,hurd)) '()))))))
+
+(define (kernel-builder-configuration-add-modules config modules)
+  "Constructs a kernel builder configuration that has its modules extended."
+  (kernel-builder-configuration
+    (inherit config)
+    (modules (append (kernel-builder-configuration-modules config) modules))))
+
+(define kernel-loadable-module-service-type
+  (service-type (name 'kernel-loadable-modules)
+                (extensions
+                 (list (service-extension system-service-type
+                                          kernel-builder-configuration->system-entry)))
+                (compose concatenate)
+                (extend kernel-builder-configuration-add-modules)
+                (description
+                 "Register packages containing kernel-loadable modules and adds them
+to the system.")))
+
+(define (kernel-loadable-module-service kernel hurd modules)
+  "Constructs the service that sets up kernel loadable modules."
+  (service kernel-loadable-module-service-type
+    (kernel-builder-configuration
+      (kernel kernel)
+      (hurd hurd)
+      (modules modules))))
+
 \f
 ;;;
 ;;; Service folding.
diff --git a/gnu/system.scm b/gnu/system.scm
index c284a18379..5c530f176e 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -12,6 +12,7 @@
 ;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com>
 ;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <jannek@gnu.org>
 ;;; Copyright © 2020 Efraim Flashner <efraim@flashner.co.il>
+;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -600,16 +601,6 @@ OS."
       (file-append (operating-system-kernel os)
                       "/" (system-linux-image-file-name))))

-(define (package-for-kernel target-kernel module-package)
-  "Return a package like MODULE-PACKAGE, adapted for TARGET-KERNEL, if
-possible (that is if there's a LINUX keyword argument in the build system)."
-  (package
-    (inherit module-package)
-    (arguments
-     (substitute-keyword-arguments (package-arguments module-package)
-       ((#:linux kernel #f)
-        target-kernel)))))
-
 (define %default-modprobe-blacklist
   ;; List of kernel modules to blacklist by default.
   '("usbmouse" ;races with bcm5974, see <https://bugs.gnu.org/35574>
@@ -625,26 +616,10 @@ possible (that is if there's a LINUX keyword argument in the build system)."
   "Return the basic entries of the 'system' directory of OS for use as the
 value of the SYSTEM-SERVICE-TYPE service."
   (let* ((locale  (operating-system-locale-directory os))
-         (kernel  (operating-system-kernel os))
          (hurd    (operating-system-hurd os))
-         (modules (operating-system-kernel-loadable-modules os))
-         (kernel  (if hurd
-                      kernel
-                      (profile
-                       (content (packages->manifest
-                                 (cons kernel
-                                       (map (lambda (module)
-                                              (if (package? module)
-                                                  (package-for-kernel kernel
-                                                                      module)
-                                                  module))
-                                            modules))))
-                       (hooks (list linux-module-database)))))
          (initrd  (and (not hurd) (operating-system-initrd-file os)))
          (params  (operating-system-boot-parameters-file os)))
-    `(("kernel" ,kernel)
-      ,@(if hurd `(("hurd" ,hurd)) '())
-      ("parameters" ,params)
+    `(("parameters" ,params)
       ,@(if initrd `(("initrd" ,initrd)) '())
       ("locale" ,locale))))   ;used by libc

@@ -663,6 +638,10 @@ bookkeeping."
          (host-name (host-name-service (operating-system-host-name os)))
          (entries   (operating-system-directory-base-entries os)))
     (cons* (service system-service-type entries)
+           (kernel-loadable-module-service
+             (operating-system-kernel os)
+             (operating-system-hurd os)
+             (operating-system-kernel-loadable-modules os))
            %boot-service

            ;; %SHEPHERD-ROOT-SERVICE must come last so that the gexp that
@@ -699,6 +678,10 @@ bookkeeping."
 (define (hurd-default-essential-services os)
   (let ((entries (operating-system-directory-base-entries os)))
     (list (service system-service-type entries)
+          (kernel-loadable-module-service
+            (operating-system-kernel os)
+            (operating-system-hurd os)
+            (operating-system-kernel-loadable-modules os))
           %boot-service
           %hurd-startup-service
           %activation-service
diff --git a/gnu/tests/linux-modules.scm b/gnu/tests/linux-modules.scm
index 953b132ef7..9739e4124d 100644
--- a/gnu/tests/linux-modules.scm
+++ b/gnu/tests/linux-modules.scm
@@ -2,6 +2,7 @@
 ;;; Copyright © 2019 Jakob L. Kreuze <zerodaysfordays@sdf.org>
 ;;; Copyright © 2020 Danny Milosavljevic <dannym@scratchpost.org>
 ;;; Copyright © 2020 Brice Waegeneire <brice@waegenei.re>
+;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -34,7 +35,10 @@
   #:use-module (guix utils)
   #:export (%test-loadable-kernel-modules-0
             %test-loadable-kernel-modules-1
-            %test-loadable-kernel-modules-2))
+            %test-loadable-kernel-modules-2
+            %test-loadable-kernel-modules-service-0
+            %test-loadable-kernel-modules-service-1
+            %test-loadable-kernel-modules-service-2))

 ;;; Commentary:
 ;;;
@@ -66,17 +70,11 @@ that MODULES are actually loaded."
                        (member module modules string=?))
                      '#$modules))))))

-(define* (run-loadable-kernel-modules-test module-packages module-names)
-  "Run a test of an OS having MODULE-PACKAGES, and verify that MODULE-NAMES
-are loaded in memory."
+(define* (run-loadable-kernel-modules-test-base base-os module-names)
+  "Run a test of BASE-OS, verifying that MODULE-NAMES are loaded in memory."
   (define os
     (marionette-operating-system
-     (operating-system
-      (inherit (simple-operating-system))
-      (services (cons (service kernel-module-loader-service-type module-names)
-                      (operating-system-user-services
-                       (simple-operating-system))))
-      (kernel-loadable-modules module-packages))
+     base-os
      #:imported-modules '((guix combinators))))
   (define vm (virtual-machine os))
   (define (test script)
@@ -98,6 +96,37 @@ are loaded in memory."
   (gexp->derivation "loadable-kernel-modules"
                     (test (modules-loaded?-program os module-names))))

+(define* (run-loadable-kernel-modules-test module-packages module-names)
+  "Run a test of an OS having MODULE-PACKAGES, and verify that MODULE-NAMES
+are loaded in memory."
+  (run-loadable-kernel-modules-test-base
+    (operating-system
+      (inherit (simple-operating-system))
+      (services (cons (service kernel-module-loader-service-type module-names)
+                      (operating-system-user-services
+                       (simple-operating-system))))
+      (kernel-loadable-modules module-packages))
+    module-names))
+
+(define* (run-loadable-kernel-modules-service-test module-packages module-names)
+  "Run a test of an OS having MODULE-PACKAGES, which are loaded by creating a
+service that extends KERNEL-LOADABLE-MODULE-SERVICE-TYPE. Then verify that
+MODULE-NAMES are loaded in memory."
+  (define module-installing-service-type
+    (service-type
+      (name 'module-installing-service)
+      (extensions (list (service-extension kernel-loadable-module-service-type
+                                           (const module-packages))))
+      (default-value #f)))
+  (run-loadable-kernel-modules-test-base
+    (operating-system
+      (inherit (simple-operating-system))
+      (services (cons* (service kernel-module-loader-service-type module-names)
+                       (service module-installing-service-type)
+                       (operating-system-user-services
+                        (simple-operating-system)))))
+    module-names))
+
 (define %test-loadable-kernel-modules-0
   (system-test
    (name "loadable-kernel-modules-0")
@@ -129,3 +158,35 @@ with two extra modules.")
                                                  (package-arguments
                                                   ddcci-driver-linux))))))
            '("acpi_call" "ddcci")))))
+
+(define %test-loadable-kernel-modules-service-0
+  (system-test
+   (name "loadable-kernel-modules-service-0")
+   (description "Tests loadable kernel modules extensible service with no
+extra modules.")
+   (value (run-loadable-kernel-modules-service-test '() '()))))
+
+(define %test-loadable-kernel-modules-service-1
+  (system-test
+   (name "loadable-kernel-modules-service-1")
+   (description "Tests loadable kernel modules extensible service with one
+extra module.")
+   (value (run-loadable-kernel-modules-service-test
+           (list ddcci-driver-linux)
+           '("ddcci")))))
+
+(define %test-loadable-kernel-modules-service-2
+  (system-test
+   (name "loadable-kernel-modules-service-2")
+   (description "Tests loadable kernel modules extensible service with two
+extra modules.")
+   (value (run-loadable-kernel-modules-service-test
+           (list acpi-call-linux-module
+                 (package
+                   (inherit ddcci-driver-linux)
+                   (arguments
+                    `(#:linux #f
+                      ,@(strip-keyword-arguments '(#:linux)
+                                                 (package-arguments
+                                                  ddcci-driver-linux))))))
+           '("acpi_call" "ddcci")))))
--
2.29.2