From e9fa17eb98efbd6211ab44ab49b8c078d4b73e04 Mon Sep 17 00:00:00 2001 From: Maxim Cournoyer Date: Tue, 1 Feb 2022 00:32:50 -0500 Subject: services: udev: Use a fixed location for the rules directory and config. Fixes . This change adjusts the location of the udev configuration file and rules directory to a fixed location. Since udev relies on inotify to discover change to its rules directory (/etc/udev/rules.d), by using a fixed directory layout, new udev rules can be automatically picked up without restarting the service. * gnu/services/base.scm (udev-rules-union): Build rules output directly in #$output. (udev-shepherd-service)[start]: Adjust the UDEV_CONFIG_FILE and EUDEV_RULES_DIRECTORY environment variables. [actions]: Remove field. The 'rules' action is no longer useful. (udev.conf): New variable. (udev-etc): New procedure. (udev-service-type): Extend the etc-service-type with it. --- gnu/services/base.scm | 210 +++++++++++++++++++++++++------------------------- 1 file changed, 104 insertions(+), 106 deletions(-) (limited to 'gnu/services') diff --git a/gnu/services/base.scm b/gnu/services/base.scm index fbd01e84d6..4c8a840156 100644 --- a/gnu/services/base.scm +++ b/gnu/services/base.scm @@ -15,7 +15,7 @@ ;;; Copyright © 2020, 2021 Brice Waegeneire ;;; Copyright © 2021 qblade ;;; Copyright © 2021 Hui Lu -;;; Copyright © 2021 Maxim Cournoyer +;;; Copyright © 2021, 2022 Maxim Cournoyer ;;; Copyright © 2022 Guillaume Le Vaillant ;;; ;;; This file is part of GNU Guix. @@ -1995,8 +1995,7 @@ item of @var{packages}." (find directory-exists? (map (cut string-append directory <>) %standard-locations))) - (mkdir-p (string-append #$output "/lib/udev")) - (union-build (string-append #$output "/lib/udev/rules.d") + (union-build #$output (filter-map rules-sub-directory '#$packages))))) (computed-file "udev-rules" build)) @@ -2045,116 +2044,115 @@ item of @var{packages}." (define udev-shepherd-service ;; Return a for UDEV with RULES. + (match-lambda + (($ udev) + (list + (shepherd-service + (provision '(udev)) + + ;; Udev needs /dev to be a 'devtmpfs' mount so that new device nodes can + ;; be added: see + ;; . + (requirement '(root-file-system)) + + (documentation "Populate the /dev directory, dynamically.") + (start + (with-imported-modules (source-module-closure + '((gnu build linux-boot))) + #~(lambda () + (define udevd + ;; 'udevd' from eudev. + #$(file-append udev "/sbin/udevd")) + + (define (wait-for-udevd) + ;; Wait until someone's listening on udevd's control + ;; socket. + (let ((sock (socket AF_UNIX SOCK_SEQPACKET 0))) + (let try () + (catch 'system-error + (lambda () + (connect sock PF_UNIX "/run/udev/control") + (close-port sock)) + (lambda args + (format #t "waiting for udevd...~%") + (usleep 500000) + (try)))))) + + ;; Allow udev to find the modules. + (setenv "LINUX_MODULE_DIRECTORY" + "/run/booted-system/kernel/lib/modules") + + (let* ((kernel-release + (utsname:release (uname))) + (linux-module-directory + (getenv "LINUX_MODULE_DIRECTORY")) + (directory + (string-append linux-module-directory "/" + kernel-release)) + (old-umask (umask #o022))) + ;; If we're in a container, DIRECTORY might not exist, + ;; for instance because the host runs a different + ;; kernel. In that case, skip it; we'll just miss a few + ;; nodes like /dev/fuse. + (when (file-exists? directory) + (make-static-device-nodes directory)) + (umask old-umask)) + + (let ((pid (fork+exec-command + (list udevd) + #:environment-variables + (cons* + ;; The first one is for udev, the second one for + ;; eudev. + "UDEV_CONFIG_FILE=/etc/udev/udev.conf" + "EUDEV_RULES_DIRECTORY=/etc/udev/rules.d" + (string-append "LINUX_MODULE_DIRECTORY=" + (getenv "LINUX_MODULE_DIRECTORY")) + (default-environment-variables))))) + ;; Wait until udevd is up and running. This appears to + ;; be needed so that the events triggered below are + ;; actually handled. + (wait-for-udevd) + + ;; Trigger device node creation. + (system* #$(file-append udev "/bin/udevadm") + "trigger" "--action=add") + + ;; Wait for things to settle down. + (system* #$(file-append udev "/bin/udevadm") + "settle") + pid)))) + (stop #~(make-kill-destructor)) + + ;; When halting the system, 'udev' is actually killed by + ;; 'user-processes', i.e., before its own 'stop' method was called. + ;; Thus, make sure it is not respawned. + (respawn? #f) + ;; We need additional modules. + (modules `((gnu build linux-boot) ;'make-static-device-nodes' + ,@%default-modules))))))) + +(define udev.conf + (computed-file "udev.conf" + #~(call-with-output-file #$output + (lambda (port) + (format port "udev_rules=\"/etc/udev/rules.d\"~%"))))) + +(define udev-etc (match-lambda (($ udev rules) - (let* ((rules (udev-rules-union (cons* udev kvm-udev-rule rules))) - (udev.conf (computed-file "udev.conf" - #~(call-with-output-file #$output - (lambda (port) - (format port - "udev_rules=\"~a/lib/udev/rules.d\"\n" - #$rules)))))) - (list - (shepherd-service - (provision '(udev)) - - ;; Udev needs /dev to be a 'devtmpfs' mount so that new device nodes can - ;; be added: see - ;; . - (requirement '(root-file-system)) - - (documentation "Populate the /dev directory, dynamically.") - (start - (with-imported-modules (source-module-closure - '((gnu build linux-boot))) - #~(lambda () - (define udevd - ;; 'udevd' from eudev. - #$(file-append udev "/sbin/udevd")) - - (define (wait-for-udevd) - ;; Wait until someone's listening on udevd's control - ;; socket. - (let ((sock (socket AF_UNIX SOCK_SEQPACKET 0))) - (let try () - (catch 'system-error - (lambda () - (connect sock PF_UNIX "/run/udev/control") - (close-port sock)) - (lambda args - (format #t "waiting for udevd...~%") - (usleep 500000) - (try)))))) - - ;; Allow udev to find the modules. - (setenv "LINUX_MODULE_DIRECTORY" - "/run/booted-system/kernel/lib/modules") - - (let* ((kernel-release - (utsname:release (uname))) - (linux-module-directory - (getenv "LINUX_MODULE_DIRECTORY")) - (directory - (string-append linux-module-directory "/" - kernel-release)) - (old-umask (umask #o022))) - ;; If we're in a container, DIRECTORY might not exist, - ;; for instance because the host runs a different - ;; kernel. In that case, skip it; we'll just miss a few - ;; nodes like /dev/fuse. - (when (file-exists? directory) - (make-static-device-nodes directory)) - (umask old-umask)) - - (let ((pid (fork+exec-command (list udevd) - #:environment-variables - (cons* - ;; The first one is for udev, the second one for - ;; eudev. - (string-append "UDEV_CONFIG_FILE=" #$udev.conf) - (string-append "EUDEV_RULES_DIRECTORY=" - #$(file-append - rules "/lib/udev/rules.d")) - (string-append "LINUX_MODULE_DIRECTORY=" - (getenv "LINUX_MODULE_DIRECTORY")) - (default-environment-variables))))) - ;; Wait until udevd is up and running. This appears to - ;; be needed so that the events triggered below are - ;; actually handled. - (wait-for-udevd) - - ;; Trigger device node creation. - (system* #$(file-append udev "/bin/udevadm") - "trigger" "--action=add") - - ;; Wait for things to settle down. - (system* #$(file-append udev "/bin/udevadm") - "settle") - pid)))) - (stop #~(make-kill-destructor)) - - ;; When halting the system, 'udev' is actually killed by - ;; 'user-processes', i.e., before its own 'stop' method was called. - ;; Thus, make sure it is not respawned. - (respawn? #f) - ;; We need additional modules. - (modules `((gnu build linux-boot) ;'make-static-device-nodes' - ,@%default-modules)) - - (actions (list (shepherd-action - (name 'rules) - (documentation "Display the directory containing -the udev rules in use.") - (procedure #~(lambda (_) - (display #$rules) - (newline)))))))))))) + `(("udev" + ,(file-union + "udev" `(("udev.conf" ,udev.conf) + ("rules.d" ,(udev-rules-union (cons* udev kvm-udev-rule + rules)))))))))) (define udev-service-type (service-type (name 'udev) (extensions (list (service-extension shepherd-root-service-type - udev-shepherd-service))) - + udev-shepherd-service) + (service-extension etc-service-type udev-etc))) (compose concatenate) ;concatenate the list of rules (extend (lambda (config rules) (match config -- cgit v1.2.3