From 145b51aeb35b02f0eb43ef3c31d0b2b77551424e Mon Sep 17 00:00:00 2001 From: Karl Hallsby Date: Fri, 10 Jan 2025 01:00:59 -0600 Subject: [PATCH] services: Add xe-guest-utilities-service-type. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * gnu/services/virtualization.scm (xe-guest-utilities-configuration, xe-guest-utilities-service-type): New variables. * doc/guix.texi: Document them. Change-Id: Ife4e79fa6d1a9d5a21bf7479488884f2a5cf8d56 Signed-off-by: Ludovic Courtès --- doc/guix.texi | 71 ++++++++++++++++++++++++++++ gnu/services/virtualization.scm | 82 ++++++++++++++++++++++++++++++++- 2 files changed, 152 insertions(+), 1 deletion(-) diff --git a/doc/guix.texi b/doc/guix.texi index 3cf1fedc30..67b7dc4166 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -37518,6 +37518,77 @@ host. If empty, QEMU uses a default file name. @end table @end deftp +@subsubheading Xen Guest Agent + +@cindex Xen +@cindex Xen guest agent + +The Xen guest agent allows a Xen host to control the emulated system. +The @code{xe-guest-utilities} service runs the agent on Guix guests. + +@url{https://github.com/xenserver/xe-guest-utilities, xe-guest-utilities} collects information about the running virtualized guest. This includes: +@itemize +@item +static information +@itemize +@item +The operating system running +@item +The Linux kernel version +@end itemize + +@item +dynamic information +@itemize +@item +Network interfaces (devices) being added/removed +@item +Network connections being unplugged/plugged-in +@item +CPUs being added or removed +@item +The guest migrating, being paused/resumed, etc. +@end itemize + +@item +ephemeral information +@itemize +@item +The amount of memory currently in-use and free +@item +The amount of disk-space used +@end itemize +@end itemize + +@quotation Note +The default Linux-libre kernel that Guix ships already enables the +necessary paravirtualization features for a guest. There is nothing you +need to do for the guest to support Xen's paravirtualization features. + +The guest utilities are used to have the guest report information +@emph{back} to the virtualizing host and support tasks that require +cooperation between host and guest, like CPU hotplugging. +@end quotation + +@defvar xe-guest-utilities-service-type +Service type for the Xen guest utilities service. +@end defvar + +@deftp {Data Type} xe-guest-utilities-configuration +Configuration for the @code{xe-guest-utilities} service. + +@table @asis +@item @code{package} (default: @code{xe-guest-utilities}) +The Xen guest utilities package to use. + +@item @code{pid-file} (default: @code{"/var/run/xe-daemon.pid"}) +Name of the file holding the PID of @code{xe-deamon}. + +@item @code{log-file} (default: @code{"/var/log/xe-guest-utilities.log"}) +Name of the @code{xe-guest-utilities} log file. +@end table +@end deftp + @anchor{build-vm} @subsubheading Virtual Build Machines diff --git a/gnu/services/virtualization.scm b/gnu/services/virtualization.scm index 53f79e367b..874abcd73f 100644 --- a/gnu/services/virtualization.scm +++ b/gnu/services/virtualization.scm @@ -6,6 +6,7 @@ ;;; Copyright © 2022 Oleg Pykhalov ;;; Copyright © 2022 Leo Nikkilä ;;; Copyright © 2023 Efraim Flashner +;;; Copyright © 2024 Raven Hallsby ;;; ;;; This file is part of GNU Guix. ;;; @@ -32,6 +33,9 @@ (define-module (gnu services virtualization) #:autoload (gnu packages gnupg) (guile-gcrypt) #:use-module (gnu packages package-management) #:use-module (gnu packages ssh) + #:use-module (gnu packages base) + #:use-module (gnu packages gawk) + #:use-module (gnu packages linux) #:use-module (gnu packages virtualization) #:use-module (gnu services base) #:use-module (gnu services configuration) @@ -106,7 +110,10 @@ (define-module (gnu services virtualization) qemu-guest-agent-configuration qemu-guest-agent-configuration? - qemu-guest-agent-service-type)) + qemu-guest-agent-service-type + + xe-guest-utilities-configuration + xe-guest-utilities-service-type)) (define (uglify-field-name field-name) (let ((str (symbol->string field-name))) @@ -1003,6 +1010,79 @@ (define qemu-guest-agent-service-type (default-value (qemu-guest-agent-configuration)) (description "Run the QEMU guest agent."))) + +;;; +;;; Guest agent for VMs running under Xen +;;; +(define-configuration/no-serialization xe-guest-utilities-configuration + (package + (package xe-guest-utilities) + "Xen guest management utilities package.") + (pid-file + (string "/var/run/xe-daemon.pid") + "Path to the file holding the PID of xe-deamon.") + (log-file + (string "/var/log/xe-guest-utilties.log") + "Path to xe-guest-utilities log file.")) + +(define (generate-xe-guest-utilities-documentation) + "Generate documentation for xe-guest-utilities-configuration fields" + (generate-documentation + `((xe-guest-utilities-configuration ,xe-guest-utilities-configuration-fields)) + 'xe-guest-utilities-configuration)) + +(define (xe-guest-utilities-shepherd-service config) + (let ((xe-guest-utils (xe-guest-utilities-configuration-package config)) + (pid-file (xe-guest-utilities-configuration-pid-file config)) + (log-file (xe-guest-utilities-configuration-log-file config))) + (list + (shepherd-service + (provision '(xen-guest-agent)) + (requirement '(networking user-processes udev)) + (documentation "Run the Xen guest management agent.") + (start + #~(lambda _ + (let ((pid (make-forkexec-constructor + (list + #$(file-append xe-guest-utils + "/sbin/xe-daemon") + "-p" #$pid-file) + #:log-file #$log-file + #:pid-file #$pid-file + #:environment-variables + (list (string-append + "PATH=" + #$(file-append xe-guest-utils "/bin") ":" + ;; logger + #$(file-append inetutils "/bin")))))) + ;; Run xe-linux-distribution script before starting the actual + ;; daemon. The script collects some basic system information that + ;; is shared back to the Xen host. + (system* #$(file-append xe-guest-utils "/sbin/xe-linux-distribution") + "/var/cache/xe-linux-distribution") + ;; Finally, start and return the PID made by + ;; make-forkexec-constructor. + pid))) + (stop #~(make-kill-destructor)))))) + +(define (xe-guest-utilities-udev-rules-service config) + (let ((guest-utils (xe-guest-utilities-configuration-package config))) + (list + (file->udev-rule + "z10_xen-vcpu-hotplug.rules" + (file-append guest-utils "/lib/udev/rules.d/z10_xen-vcpu-hotplug.rules"))))) + +(define xe-guest-utilities-service-type + (service-type + (name 'xe-guest-utilities) + (extensions + (list (service-extension shepherd-root-service-type + xe-guest-utilities-shepherd-service) + (service-extension udev-service-type + xe-guest-utilities-udev-rules-service))) + (default-value (xe-guest-utilities-configuration)) + (description "Run the Xen guest management utilities."))) + ;;; ;;; Secrets for guest VMs.