Hi guix-developers,
Another issue here is that ZFS prefers to not be managed via
`/etc/fstab`/`mount`/`umount`. Instead, at startup ZFS magically imports ZFS
pools and mounts ZFS datasets in the correct place, as configured in the
`mountpoint` properties of the dataset. This magic is actually implemented by
executing `zpool import -a` at startup after ZFS module loading. Note that
`zpool import -a` has to be executed always so that ZFS can detect its pools,
though the automatic mounting can be suppressed with `zpool import -a -N`.
(`systemd`-based distros have a number of `systemd` services that handle ZFS
importation by use of a `/etc/zfs/zpool.cache` file that ZFS maintains, and
then does `zfs mount -a` to do automounting, but I'll leave that for later.)
Now, properly speaking, the shepherd `file-systems` service should not be
started until we have actually performed ZFS automounting. This means that
`file-systems` has to have as a requirement the ZFS shepherd service that
implements the automounting. And of course it should *not* require that if ZFS
isn't installed in the system.
So, I made another patch that makes the `file-systems` shepherd service have an
extensible set of requirements, like `user-processes` does. It's below.
Actual `file-system`s declared in the operating system then make themselves
requirements of `file-systems`. Then, a ZFS automounting shepherd service can
be installed by the `zfs-service-type` and added as a requirement of the
`file-systems` shepherd service.
This is important since one possible use of ZFS is to have it provide the
`/home` filesystem. And the `/home` filesystem has to be mounted before
`user-homes` shepherd service starts. So the ZFS automounting shepherd service
has to be a requirement of `file-systems`, which is enabled by the below.
Please review!
>From 792a8f8efc95e4fe9a94d42f839ddcfb034b8540 Mon Sep 17 00:00:00 2001
From: raid5atemyhomework <raid5atemyhomew...@protonmail.com>
Date: Wed, 6 Jan 2021 08:15:54 +0800
Subject: [PATCH] gnu: Make file-systems target extensible by services.
* gnu/services/base.scm (file-system-shepherd-services): Move file-systems
shepherd service to ...
(file-systems-target-shepherd-services): ... new procedure here.
(file-systems-target-service-type): New variable.
(file-system-service-type): Extend file-systems-target service to add each
file-system as a requirement.
* gnu/system.scm (operating-system-default-essential-services): Instantiate
file-systems-target-service-type.
(hurd-default-essential-services): Instantiate file-systems-target-service-type.
---
gnu/services/base.scm | 37 +++++++++++++++++++++++++++----------
gnu/system.scm | 2 ++
2 files changed, 29 insertions(+), 10 deletions(-)
diff --git a/gnu/services/base.scm b/gnu/services/base.scm
index 945b546607..13cfb6a8a2 100644
--- a/gnu/services/base.scm
+++ b/gnu/services/base.scm
@@ -13,6 +13,7 @@
;;; Copyright © 2019 Jan (janneke) Nieuwenhuizen <jann...@gnu.org>
;;; Copyright © 2020 Florian Pelz <pelzflor...@pelzflorian.de>
;;; Copyright © 2020 Brice Waegeneire <br...@waegenei.re>
+;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomew...@protonmail.com>
;;;
;;; This file is part of GNU Guix.
;;;
@@ -67,6 +68,7 @@
#:export (fstab-service-type
root-file-system-service
file-system-service-type
+ file-systems-target-service-type
swap-service
host-name-service
console-keymap-service
@@ -362,18 +364,29 @@ FILE-SYSTEM."
(gnu system file-systems)
,@%default-modules)))))))
+(define (file-systems-target-shepherd-services requirements)
+ (list
+ (shepherd-service
+ (provision '(file-systems))
+ (requirement (cons* 'root-file-system 'user-file-systems requirements))
+ (documentation "Target for all the initially-mounted file systems")
+ (start #~(const #t))
+ (stop #~(const #t)))))
+(define file-systems-target-service-type
+ (service-type
+ (name 'file-systems)
+ (extensions (list (service-extension shepherd-root-service-type
+
file-systems-target-shepherd-services)))
+ (compose concatenate)
+ (extend append)
+ ;; Extensions can add new values to this list.
+ (default-value '())
+ (description "The @code{file-systems} service is the target that is started
+when all file systems have been mounted.")))
+
(define (file-system-shepherd-services file-systems)
"Return the list of Shepherd services for FILE-SYSTEMS."
(let* ((file-systems (filter file-system-mount? file-systems)))
- (define sink
- (shepherd-service
- (provision '(file-systems))
- (requirement (cons* 'root-file-system 'user-file-systems
- (map file-system->shepherd-service-name
- file-systems)))
- (documentation "Target for all the initially-mounted file systems")
- (start #~(const #t))
- (stop #~(const #f))))
(define known-mount-points
(map file-system-mount-point file-systems))
@@ -403,7 +416,7 @@ FILE-SYSTEM."
(filter (negate known?) (mount-points)))
#f))))
- (cons* sink user-unmount
+ (cons* user-unmount
(map file-system-shepherd-service file-systems))))
(define (file-system-fstab-entries file-systems)
@@ -431,6 +444,10 @@ FILE-SYSTEM."
(service-extension fstab-service-type
file-system-fstab-entries)
+ ;; Have 'file-systems' depend on each declared file
system.
+ (service-extension file-systems-target-service-type
+ (cut map
file-system->shepherd-service-name <>))
+
;; Have 'user-processes' depend on 'file-systems'.
(service-extension user-processes-service-type
(const '(file-systems)))))
diff --git a/gnu/system.scm b/gnu/system.scm
index 5c530f176e..6987641ee8 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -667,6 +667,7 @@ bookkeeping."
(operating-system-setuid-programs os))
(service profile-service-type
(operating-system-packages os))
+ (service file-systems-target-service-type)
other-fs
(append mappings swaps
@@ -691,6 +692,7 @@ bookkeeping."
(operating-system-groups os))
(operating-system-skeletons os))
(root-file-system-service)
+ (service file-systems-target-service-type)
(service file-system-service-type '())
(service fstab-service-type
(filter file-system-needed-for-boot?
--
2.29.2
