bug#40998: [PATCH 1/4] system: Add a version field to the <boot-parameters> record.

bug#40998: [PATCH 1/4] system: Add a version field to the <boot-parameters> record.

[Maxim Cournoyer]

This version field exposes the (already present) version information of a boot
parameters file.

* gnu/system.scm (%boot-parameters-version): New variable.
(<boot-parameters>)[version]: New field.
(read-boot-parameters): Use it.
(operating-system-boot-parameters-file): Likewise.
* tests/boot-parameters.scm (test-read-boot-parameters): Use
%boot-parameters-version as the default version value in the template.
---
 gnu/system.scm            | 20 ++++++++++++++++----
 tests/boot-parameters.scm |  2 +-
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/gnu/system.scm b/gnu/system.scm
index cc925de16f..9ae158dea6 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -9,7 +9,7 @@
 ;;; Copyright © 2020 Danny Milosavljevic <dannym@scratchpost.org>
 ;;; Copyright © 2020, 2021 Brice Waegeneire <brice@waegenei.re>
 ;;; Copyright © 2020 Florian Pelz <pelzflorian@pelzflorian.de>
-;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com>
+;;; Copyright © 2020, 2022 Maxim Cournoyer <maxim.cournoyer@gmail.com>
 ;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <jannek@gnu.org>
 ;;; Copyright © 2020 Efraim Flashner <efraim@flashner.co.il>
 ;;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
@@ -161,6 +161,8 @@ (define-module (gnu system)
             boot-parameters-kernel-arguments
             boot-parameters-initrd
             boot-parameters-multiboot-modules
+            boot-parameters-version
+            %boot-parameters-version
             read-boot-parameters
             read-boot-parameters-file
             boot-parameters->menu-entry
@@ -295,6 +297,8 @@ (define (operating-system-kernel-arguments os root-device)
 ;;; Boot parameters
 ;;;
 
+(define %boot-parameters-version 0)
+
 (define-record-type* <boot-parameters>
   boot-parameters make-boot-parameters boot-parameters?
   (label            boot-parameters-label)
@@ -322,7 +326,9 @@ (define-record-type* <boot-parameters>
   (kernel           boot-parameters-kernel)
   (kernel-arguments boot-parameters-kernel-arguments)
   (initrd           boot-parameters-initrd)
-  (multiboot-modules boot-parameters-multiboot-modules))
+  (multiboot-modules boot-parameters-multiboot-modules)
+  (version          boot-parameters-version  ;positive integer
+                    (default %boot-parameters-version)))
 
 (define (ensure-not-/dev device)
   "If DEVICE starts with a slash, return #f.  This is meant to filter out
@@ -359,12 +365,18 @@ (define uuid-sexp->uuid
        (warning (G_ "unrecognized uuid ~a at '~a'~%") x (port-filename port))
        #f)))
 
+  ;; New versions are not backward-compatible, so only accept past and current
+  ;; versions, not future ones.
+  (define (version? n)
+    (member n (iota (1+ %boot-parameters-version))))
+
   (match (read port)
-    (('boot-parameters ('version 0)
+    (('boot-parameters ('version (? version? version))
                        ('label label) ('root-device root)
                        ('kernel kernel)
                        rest ...)
      (boot-parameters
+      (version version)
       (label label)
       (root-device (device-sexp->device root))
 
@@ -1500,7 +1512,7 @@ (define* (operating-system-boot-parameters-file os
                    system-kernel-arguments?)))
      (scheme-file "parameters"
                   #~(boot-parameters
-                     (version 0)
+                     (version #$(boot-parameters-version params))
                      (label #$(boot-parameters-label params))
                      (root-device
                       #$(device->sexp
diff --git a/tests/boot-parameters.scm b/tests/boot-parameters.scm
index b2799d0596..d4b680df2e 100644
--- a/tests/boot-parameters.scm
+++ b/tests/boot-parameters.scm
@@ -101,7 +101,7 @@ (define (quote-uuid uuid)
 ;; Call read-boot-parameters with the desired string as input.
 (define* (test-read-boot-parameters
           #:key
-          (version 0)
+          (version %boot-parameters-version)
           (bootloader-name 'grub)
           (bootloader-menu-entries '())
           (label %default-label)
-- 
2.34.0

bug#40998: [PATCH 2/4] system: Streamline operating-system-boot-parameters-file a bit.

[Maxim Cournoyer]

* gnu/system.scm (operating-system-boot-parameters-file)
[SYSTEM-KERNEL-ARGUMENTS?]: Remove unused argument (it had no callers) and
adjust doc, moving the self-referential tip to...
* gnu/system.scm (operating-system-boot-parameters): ... here, reworded for
clarity.

Suggested-by: Ludovic Courtès <ludo@gnu.org>
---
 gnu/system.scm | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/gnu/system.scm b/gnu/system.scm
index 9ae158dea6..c6c46343cc 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -1453,7 +1453,10 @@ (define* (operating-system-boot-parameters os root-device
                                            #:key system-kernel-arguments?)
   "Return a monadic <boot-parameters> record that describes the boot
 parameters of OS.  When SYSTEM-KERNEL-ARGUMENTS? is true, add kernel arguments
-such as '--root' and '--load' to <boot-parameters>."
+such as '--root' and '--load' to <boot-parameters>.  The
+SYSTEM-KERNEL-ARGUMENTS? should only be used in necessity, as the '--load' and
+'--system' values are self-referential (they refer to the system), thus
+susceptible to introduce a cyclic dependency."
   (let* ((initrd          (and (not (operating-system-hurd os))
                                (operating-system-initrd-file os)))
          (store           (operating-system-store-file-system os))
@@ -1494,22 +1497,13 @@ (define (device->sexp device)
     (_
      device)))
 
-(define* (operating-system-boot-parameters-file os
-                                                #:key system-kernel-arguments?)
-   "Return a file that describes the boot parameters of OS.  The primary use of
-this file is the reconstruction of GRUB menu entries for old configurations.
-
-When SYSTEM-KERNEL-ARGUMENTS? is true, add kernel arguments such as '--root'
-and '--load' to the returned file (since the returned file is then usually
-stored into the content-addressed \"system\" directory, it's usually not a
-good idea to give it because the content hash would change by the content hash
-being stored into the \"parameters\" file)."
+(define* (operating-system-boot-parameters-file os)
+   "Return a file that describes the boot parameters of OS.  The primary use
+of this file is the reconstruction of GRUB menu entries for old
+configurations."
    (let* ((root   (operating-system-root-file-system os))
           (device (file-system-device root))
-          (params (operating-system-boot-parameters
-                   os device
-                   #:system-kernel-arguments?
-                   system-kernel-arguments?)))
+          (params (operating-system-boot-parameters os device)))
      (scheme-file "parameters"
                   #~(boot-parameters
                      (version #$(boot-parameters-version params))
-- 
2.34.0

bug#40998: [PATCH 3/4] initrd: Use non-hyphenated kernel command-line parameter names.

[Maxim Cournoyer]

This is to make it less surprising, given the common convention sets forth by
the kernel Linux command-line parameters.

* gnu/build/linux-boot.scm (boot-system): Rename '--load', '--repl', '--root'
and '--system' to 'gnu.load', 'gnu.repl', 'root' and 'gnu.system',
respectively.  Adjust doc.
(find-long-option): Adjust doc.
* gnu/installer/parted.scm (installer-root-partition-path): Adjust accordingly.
* gnu/system.scm (bootable-kernel-arguments): Add a VERSION argument and
update doc.  Use VERSION to conditionally return old style vs new style initrd
arguments.
(%boot-parameters-version): Increment to 1.
(operating-system-boot-parameters): Adjust doc.
(operating-system-boot-parameters-file): Likewise.
* gnu/system/linux-initrd.scm (raw-initrd, base-initrd): Likewise.
* doc/guix.texi: Adjust doc.
* gnu/build/activation.scm (boot-time-system): Adjust accordingly.
* gnu/build/hurd-boot.scm (boot-hurd-system): Likewise.
* gnu/packages/commencement.scm (%final-inputs-riscv64): Adjust comment.
---
 doc/guix.texi                 | 12 ++++-----
 gnu/build/activation.scm      |  4 +--
 gnu/build/hurd-boot.scm       | 12 ++++-----
 gnu/build/linux-boot.scm      | 31 ++++++++++++-----------
 gnu/installer/parted.scm      |  2 +-
 gnu/machine/ssh.scm           |  5 ++--
 gnu/packages/commencement.scm |  4 +--
 gnu/system.scm                | 47 ++++++++++++++++++++++-------------
 gnu/system/linux-initrd.scm   |  4 +--
 9 files changed, 68 insertions(+), 53 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 1e8b23ad7e..ce44eb3b47 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -34959,7 +34959,7 @@ honors several options passed on the Linux kernel command line
 @code{-append} option of QEMU), notably:
 
 @table @code
-@item --load=@var{boot}
+@item gnu.load=@var{boot}
 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
 program, once it has mounted the root file system.
 
@@ -34967,7 +34967,7 @@ Guix uses this option to yield control to a boot program that runs the
 service activation programs and then spawns the GNU@tie{}Shepherd, the
 initialization system.
 
-@item --root=@var{root}
+@item root=@var{root}
 Mount @var{root} as the root file system.  @var{root} can be a device
 name like @code{/dev/sda1}, a file system label, or a file system UUID.
 When unspecified, the device name from the root file system of the
@@ -34992,7 +34992,7 @@ or @code{preen} to repair problems considered safe to repair automatically.
 @code{preen} is the default if this option is not present or if @var{level}
 is not one of the above.
 
-@item --system=@var{system}
+@item gnu.system=@var{system}
 Have @file{/run/booted-system} and @file{/run/current-system} point to
 @var{system}.
 
@@ -35004,7 +35004,7 @@ Instruct the initial RAM disk as well as the @command{modprobe} command
 must be a comma-separated list of module names---e.g.,
 @code{usbkbd,9pnet}.
 
-@item --repl
+@item gnu.repl
 Start a read-eval-print loop (REPL) from the initial RAM disk before it
 tries to load kernel modules and to mount the root file system.  Our
 marketing team calls it @dfn{boot-to-Guile}.  The Schemer in you will
@@ -35025,7 +35025,7 @@ here is how to use it and customize it further.
        [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
 Return a derivation that builds a raw initrd.  @var{file-systems} is
 a list of file systems to be mounted by the initrd, possibly in addition to
-the root file system specified on the kernel command line via @option{--root}.
+the root file system specified on the kernel command line via @option{root}.
 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
 @var{mapped-devices} is a list of device mappings to realize before
 @var{file-systems} are mounted (@pxref{Mapped Devices}).
@@ -35055,7 +35055,7 @@ to it are lost.
 Return as a file-like object a generic initrd, with kernel
 modules taken from @var{linux}.  @var{file-systems} is a list of file-systems to be
 mounted by the initrd, possibly in addition to the root file system specified
-on the kernel command line via @option{--root}.  @var{mapped-devices} is a list of device
+on the kernel command line via @option{root}.  @var{mapped-devices} is a list of device
 mappings to realize before @var{file-systems} are mounted.
 
 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
diff --git a/gnu/build/activation.scm b/gnu/build/activation.scm
index 9f6126023c..10c9045740 100644
--- a/gnu/build/activation.scm
+++ b/gnu/build/activation.scm
@@ -389,8 +389,8 @@ (define %current-system
   "/run/current-system")
 
 (define (boot-time-system)
-  "Return the '--system' argument passed on the kernel command line."
-  (find-long-option "--system" (if (string-contains %host-type "linux-gnu")
+  "Return the 'gnu.system' argument passed on the kernel command line."
+  (find-long-option "gnu.system" (if (string-contains %host-type "linux-gnu")
                                    (linux-command-line)
                                    (command-line))))
 
diff --git a/gnu/build/hurd-boot.scm b/gnu/build/hurd-boot.scm
index ac36bd17d4..ad3c50d61e 100644
--- a/gnu/build/hurd-boot.scm
+++ b/gnu/build/hurd-boot.scm
@@ -254,7 +254,7 @@ (define* (boot-hurd-system #:key (on-error 'debug))
   "This procedure is meant to be called from an early RC script.
 
 Install the relevant passive translators on the first boot.  Then, run system
-activation by using the kernel command-line options '--system' and '--load';
+activation by using the kernel command-line options 'gnu.system' and 'gnu.load';
 starting the Shepherd.
 
 XXX TODO: see linux-boot.scm:boot-system.
@@ -265,14 +265,14 @@ (define* (boot-hurd-system #:key (on-error 'debug))
 "
 
   (display "Welcome, this is GNU's early boot Guile.\n")
-  (display "Use '--repl' for an initrd REPL.\n\n")
+  (display "Use 'gnu.repl' for an initrd REPL.\n\n")
 
   (call-with-error-handling
    (lambda ()
 
      (let* ((args    (command-line))
-            (system  (find-long-option "--system" args))
-            (to-load (find-long-option "--load" args)))
+            (system  (find-long-option "gnu.system" args))
+            (to-load (find-long-option "gnu.load" args)))
 
        (format #t "Setting-up essential translators...\n")
        (setenv "PATH" (string-append system "/profile/bin"))
@@ -286,7 +286,7 @@ (define* (boot-hurd-system #:key (on-error 'debug))
        (unless (zero? (system* "/hurd/mach-defpager"))
          (format #t "FAILED...Good luck!\n"))
 
-       (cond ((member "--repl" args)
+       (cond ((member "gnu.repl" args)
               (format #t "Starting repl...\n")
               (start-repl))
              (to-load
@@ -298,7 +298,7 @@ (define* (boot-hurd-system #:key (on-error 'debug))
               (sleep 2)
               (reboot))
              (else
-              (display "no boot file passed via '--load'\n")
+              (display "no boot file passed via 'gnu.load'\n")
               (display "entering a warm and cozy REPL\n")
               (start-repl)))))
    #:on-error on-error))
diff --git a/gnu/build/linux-boot.scm b/gnu/build/linux-boot.scm
index 0ae316849e..cfa1ab2fcb 100644
--- a/gnu/build/linux-boot.scm
+++ b/gnu/build/linux-boot.scm
@@ -3,6 +3,7 @@
 ;;; Copyright © 2016, 2017, 2019–2021 Tobias Geerinckx-Rice <me@tobias.gr>
 ;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
 ;;; Copyright © 2019 Guillaume Le Vaillant <glv@posteo.net>
+;;; Copyright © 2020, 2022 Maxim Cournoyer <maxim.cournoyer@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -93,7 +94,7 @@ (define (linux-command-line)
      get-string-all)))
 
 (define (find-long-option option arguments)
-  "Find OPTION among ARGUMENTS, where OPTION is something like \"--load\".
+  "Find OPTION among ARGUMENTS, where OPTION is something like \"gnu.load\".
 Return the value associated with OPTION, or #f on failure."
   (let ((opt (string-append option "=")))
     (and=> (find (cut string-prefix? opt <>)
@@ -499,12 +500,12 @@ (define* (boot-system #:key
 KEYMAP-FILE is true), then setting up QEMU guest networking if
 QEMU-GUEST-NETWORKING? is true, calling PRE-MOUNT, mounting the file systems
 specified in MOUNTS, and finally booting into the new root if any.  The initrd
-supports kernel command-line options '--load', '--root', and '--repl'.  It
-also honors a subset of the documented Linux kernel command-line parameters
-such as 'fsck.mode', 'resume' and 'rootdelay'.
+supports kernel command-line parameters 'gnu.load' and 'gnu.repl'.  It also
+honors a subset of the Linux kernel command-line parameters such as
+'fsck.mode', 'resume', 'root' and 'rootdelay'.
 
-Mount the root file system, specified by the '--root' command-line argument,
-if any.
+Mount the root file system, specified by the 'root' command-line argument, if
+any.
 
 MOUNTS must be a list of <file-system> objects.
 
@@ -517,25 +518,25 @@ (define (root-mount-point? fs)
     (string=? (file-system-mount-point fs) "/"))
 
   (define (device-string->file-system-device device-string)
-    ;; The "--root=SPEC" kernel command-line option always provides a
-    ;; string, but the string can represent a device, an nfs-root, a UUID, or a
-    ;; label.  So check for all four.
+    ;; The "root=SPEC" kernel command-line option always provides a string,
+    ;; but the string can represent a device, an nfs-root, a UUID, or a label.
+    ;; So check for all four.
     (cond ((string-prefix? "/" device-string) device-string)
           ((string-contains device-string ":/") device-string) ; nfs-root
           ((uuid device-string) => identity)
           (else (file-system-label device-string))))
 
   (display "Welcome, this is GNU's early boot Guile.\n")
-  (display "Use '--repl' for an initrd REPL.\n\n")
+  (display "Use 'gnu.repl' for an initrd REPL.\n\n")
 
   (call-with-error-handling
     (lambda ()
       (mount-essential-file-systems)
       (let* ((args    (linux-command-line))
-             (to-load (find-long-option "--load" args))
-             ;; If present, ‘--root’ on the kernel command line takes precedence
+             (to-load (find-long-option "gnu.load" args))
+             ;; If present, ‘root’ on the kernel command line takes precedence
              ;; over the ‘device’ field of the root <file-system> record.
-             (root-device (and=> (find-long-option "--root" args)
+             (root-device (and=> (find-long-option "root" args)
                                  device-string->file-system-device))
              (root-fs (or (find root-mount-point? mounts)
                           ;; Fall back to fictitious defaults.
@@ -564,7 +565,7 @@ (define (repair fs)
                   (_ 'preen))
                 (file-system-repair fs))))
 
-        (when (member "--repl" args)
+        (when (member "gnu.repl" args)
           (start-repl))
 
         (display "loading kernel modules...\n")
@@ -652,7 +653,7 @@ (define (repair fs)
               (sleep 2)
               (reboot))
             (begin
-              (display "no boot file passed via '--load'\n")
+              (display "no boot file passed via 'gnu.load'\n")
               (display "entering a warm and cozy REPL\n")
               (start-repl)))))
     #:on-error on-error))
diff --git a/gnu/installer/parted.scm b/gnu/installer/parted.scm
index e33ef5f8fd..94ef9b42bc 100644
--- a/gnu/installer/parted.scm
+++ b/gnu/installer/parted.scm
@@ -348,7 +348,7 @@ (define (remove-logical-devices)
 (define (installer-root-partition-path)
   "Return the root partition path, or #f if it could not be detected."
   (let* ((cmdline (linux-command-line))
-         (root (find-long-option "--root" cmdline)))
+         (root (find-long-option "root" cmdline)))
     (and root
          (or (and (access? root F_OK) root)
              (find-partition-by-label root)
diff --git a/gnu/machine/ssh.scm b/gnu/machine/ssh.scm
index 0dc8933c82..550c989c34 100644
--- a/gnu/machine/ssh.scm
+++ b/gnu/machine/ssh.scm
@@ -422,7 +422,8 @@ (define (read-file path)
                (let* ((params (call-with-input-string serialized-params
                                 read-boot-parameters))
                       (root (boot-parameters-root-device params))
-                      (label (boot-parameters-label params)))
+                      (label (boot-parameters-label params))
+                      (version (boot-parameters-version params)))
                  (boot-parameters
                   (inherit params)
                   (label
@@ -433,7 +434,7 @@ (define (read-file path)
                                                   "~Y-~m-~d ~H:~M"))
                                   ")"))
                   (kernel-arguments
-                   (append (bootable-kernel-arguments system-path root)
+                   (append (bootable-kernel-arguments system-path root version)
                            (boot-parameters-kernel-arguments params))))))))
           generations))))
 
diff --git a/gnu/packages/commencement.scm b/gnu/packages/commencement.scm
index cdc9c1d621..9b495d8d84 100644
--- a/gnu/packages/commencement.scm
+++ b/gnu/packages/commencement.scm
@@ -3740,10 +3740,10 @@ (define-public %final-inputs
 (define-public %final-inputs-riscv64
   ;; This is similar to the added (list gcc "lib") elsewhere in this file, but
   ;; due to how (%current-system) is re-defined when performing builds with the
-  ;; '--system' flag, %final-inputs is too early in the evaulation pipeline to
+  ;; 'gnu.system' flag, %final-inputs is too early in the evaulation pipeline to
   ;; correctly identify the system for which a derivation will be built. Thus,
   ;; since (%current-system) is re-determined by (guix build-system gnu) after
-  ;; loading %final-inputs but before taking into account the '--system' flag,
+  ;; loading %final-inputs but before taking into account the 'gnu.system' flag,
   ;; the test for (target-riscv64?) needs to be in (guix build-system gnu),
   ;; with %final-inputs-riscv64 already available at the same time that
   ;; %final-inputs is available.
diff --git a/gnu/system.scm b/gnu/system.scm
index c6c46343cc..91d7e48452 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -187,16 +187,23 @@ (define-module (gnu system)
 ;;;
 ;;; Code:
 
-(define (bootable-kernel-arguments system root-device)
-  "Return a list of kernel arguments (gexps) to boot SYSTEM from ROOT-DEVICE."
-  (list (string-append "--root="
+(define* (bootable-kernel-arguments system root-device version)
+  "Return a list of kernel arguments (gexps) to boot SYSTEM from ROOT-DEVICE.
+VERSION is the target version of the boot-parameters record."
+  ;; If the version is newer than 0, we use the new style initrd parameter
+  ;; names, otherwise we use the legacy ones.  This is to maintain backward
+  ;; compatibility when producing bootloader configurations for older
+  ;; generations.
+  (define version>0? (> version 0))
+  (list (string-append (if version>0? "root=" "--root=")
                        ;; Note: Always use the DCE format because that's what
-                       ;; (gnu build linux-boot) expects for the '--root'
+                       ;; (gnu build linux-boot) expects for the 'root'
                        ;; kernel command-line option.
                        (file-system-device->string root-device
                                                    #:uuid-type 'dce))
-        #~(string-append "--system=" #$system)
-        #~(string-append "--load=" #$system "/boot")))
+        #~(string-append (if #$version>0? "gnu.system=" "--system=") #$system)
+        #~(string-append (if #$version>0? "gnu.load=" "--load=")
+                         #$system "/boot")))
 
 ;; System-wide configuration.
 ;; TODO: Add per-field docstrings/stexi.
@@ -286,10 +293,12 @@ (define-record-type* <operating-system> operating-system
                             source-properties->location))
             (innate)))
 
-(define (operating-system-kernel-arguments os root-device)
-  "Return all the kernel arguments, including the ones not specified
-directly by the user."
-  (append (bootable-kernel-arguments os root-device)
+(define* (operating-system-kernel-arguments
+          os root-device #:key (version %boot-parameters-version))
+  "Return all the kernel arguments, including the ones not specified directly
+by the user.  VERSION should match that of the target <boot-parameter> record
+object that will contain the kernel parameters."
+  (append (bootable-kernel-arguments os root-device version)
           (operating-system-user-kernel-arguments os)))
 
 \f
@@ -297,7 +306,10 @@ (define (operating-system-kernel-arguments os root-device)
 ;;; Boot parameters
 ;;;
 
-(define %boot-parameters-version 0)
+;;; Version 1 was introduced early 2022 to mark the departure from long option
+;;; names such as '--load' to the more conventional initrd option names like
+;;; 'gnu.load'.
+(define %boot-parameters-version 1)
 
 (define-record-type* <boot-parameters>
   boot-parameters make-boot-parameters boot-parameters?
@@ -478,10 +490,11 @@ (define (read-boot-parameters-file system)
 The object has its kernel-arguments extended in order to make it bootable."
   (let* ((file (string-append system "/parameters"))
          (params (call-with-input-file file read-boot-parameters))
-         (root (boot-parameters-root-device params)))
+         (root (boot-parameters-root-device params))
+         (version (boot-parameters-version params)))
     (boot-parameters
      (inherit params)
-     (kernel-arguments (append (bootable-kernel-arguments system root)
+     (kernel-arguments (append (bootable-kernel-arguments system root version)
                                (boot-parameters-kernel-arguments params))))))
 
 (define (boot-parameters->menu-entry conf)
@@ -1452,10 +1465,10 @@ (define (hurd-multiboot-modules os)
 (define* (operating-system-boot-parameters os root-device
                                            #:key system-kernel-arguments?)
   "Return a monadic <boot-parameters> record that describes the boot
-parameters of OS.  When SYSTEM-KERNEL-ARGUMENTS? is true, add kernel arguments
-such as '--root' and '--load' to <boot-parameters>.  The
-SYSTEM-KERNEL-ARGUMENTS? should only be used in necessity, as the '--load' and
-'--system' values are self-referential (they refer to the system), thus
+parameters of OS.  When SYSTEM-KERNEL-ARGUMENTS? is true, add the kernel
+arguments 'root', 'gnu.load' and 'gnu.system' to <boot-parameters>.  The
+SYSTEM-KERNEL-ARGUMENTS? should only be used in necessity, as the 'gnu.load'
+and 'gnu.system' values are self-referential (they refer to the system), thus
 susceptible to introduce a cyclic dependency."
   (let* ((initrd          (and (not (operating-system-hurd os))
                                (operating-system-initrd-file os)))
diff --git a/gnu/system/linux-initrd.scm b/gnu/system/linux-initrd.scm
index 329cd38cd6..4c4c78e444 100644
--- a/gnu/system/linux-initrd.scm
+++ b/gnu/system/linux-initrd.scm
@@ -181,7 +181,7 @@ (define* (raw-initrd file-systems
   "Return as a file-like object a raw initrd, with kernel
 modules taken from LINUX.  FILE-SYSTEMS is a list of file-systems to be
 mounted by the initrd, possibly in addition to the root file system specified
-on the kernel command line via '--root'. LINUX-MODULES is a list of kernel
+on the kernel command line via 'root'.  LINUX-MODULES is a list of kernel
 modules to be loaded at boot time. MAPPED-DEVICES is a list of device
 mappings to realize before FILE-SYSTEMS are mounted.
 HELPER-PACKAGES is a list of packages to be copied in the initrd. It may include
@@ -375,7 +375,7 @@ (define* (base-initrd file-systems
   "Return as a file-like object a generic initrd, with kernel
 modules taken from LINUX.  FILE-SYSTEMS is a list of file-systems to be
 mounted by the initrd, possibly in addition to the root file system specified
-on the kernel command line via '--root'.  MAPPED-DEVICES is a list of device
+on the kernel command line via 'root'.  MAPPED-DEVICES is a list of device
 mappings to realize before FILE-SYSTEMS are mounted.
 
 When true, KEYBOARD-LAYOUT is a <keyboard-layout> record denoting the desired
-- 
2.34.0

bug#40998: [PATCH 4/4] initrd: Honor rootfstype and rootflags command-line parameters.

[Maxim Cournoyer]

* gnu/build/linux-boot.scm (boot-system): Honor rootfstype and rootflags
arguments.  Update doc.  Error out in case there is insufficient information
with regard to the root file system.
Restore the behavior of inferring the root device from the root file system
from the operating system in case the root argument is not provided.
* doc/guix.texi (Initial RAM Disk): Document the new command-line parameters.
---
 doc/guix.texi            | 10 ++++++++
 gnu/build/linux-boot.scm | 55 ++++++++++++++++++++++++++--------------
 2 files changed, 46 insertions(+), 19 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index ce44eb3b47..dc6cb9842e 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -34973,6 +34973,16 @@ name like @code{/dev/sda1}, a file system label, or a file system UUID.
 When unspecified, the device name from the root file system of the
 operating system declaration is used.
 
+@item rootfstype=@var{type}
+Set the type of the root file system.  It overrides the @code{type}
+field of the root file system specified via the @code{operating-system}
+declaration, if any.
+
+@item rootflags=@var{options}
+Set the mount @emph{options} of the root file system.  It overrides the
+@code{options} field of the root file system specified via the
+@code{operating-system} declaration, if any.
+
 @item fsck.mode=@var{mode}
 Whether to check the @var{root} file system for errors before mounting
 it.  @var{mode} is one of @code{skip} (never check), @code{force} (always
diff --git a/gnu/build/linux-boot.scm b/gnu/build/linux-boot.scm
index cfa1ab2fcb..7d41537652 100644
--- a/gnu/build/linux-boot.scm
+++ b/gnu/build/linux-boot.scm
@@ -500,9 +500,9 @@ (define* (boot-system #:key
 KEYMAP-FILE is true), then setting up QEMU guest networking if
 QEMU-GUEST-NETWORKING? is true, calling PRE-MOUNT, mounting the file systems
 specified in MOUNTS, and finally booting into the new root if any.  The initrd
-supports kernel command-line parameters 'gnu.load' and 'gnu.repl'.  It also
+supports the kernel command-line options 'gnu.load' and 'gnu.repl'.  It also
 honors a subset of the Linux kernel command-line parameters such as
-'fsck.mode', 'resume', 'root' and 'rootdelay'.
+'fsck.mode', 'resume', 'rootdelay', rootflags and rootfstype.
 
 Mount the root file system, specified by the 'root' command-line argument, if
 any.
@@ -538,13 +538,30 @@ (define (device-string->file-system-device device-string)
              ;; over the ‘device’ field of the root <file-system> record.
              (root-device (and=> (find-long-option "root" args)
                                  device-string->file-system-device))
-             (root-fs (or (find root-mount-point? mounts)
-                          ;; Fall back to fictitious defaults.
-                          (file-system (device (or root-device "/dev/root"))
-                                       (mount-point "/")
-                                       (type "ext4"))))
+             (rootfstype  (find-long-option "rootfstype" args))
+             (rootflags   (find-long-option "rootflags" args))
+             (root-fs*    (find root-mount-point? mounts))
              (fsck.mode (find-long-option "fsck.mode" args)))
 
+        (unless (or root-fs* (and root-device rootfstype))
+          (error "no root file system or 'root' and 'rootfstype' parameters"))
+
+        ;; If present, ‘root’ on the kernel command line takes precedence over
+        ;; the ‘device’ field of the root <file-system> record; likewise for
+        ;; the 'rootfstype' and 'rootflags' arguments.
+        (define root-fs
+          (if root-fs*
+              (file-system
+                (inherit root-fs*)
+                (device (or root-device (file-system-device root-fs*)))
+                (type (or rootfstype (file-system-type root-fs*)))
+                (options (or rootflags (file-system-options root-fs*))))
+              (file-system
+                (device root-device)
+                (mount-point "/")
+                (type rootfstype)
+                (options rootflags))))
+
         (define (check? fs)
           (match fsck.mode
             ("skip"  #f)
@@ -616,18 +633,18 @@ (define (repair fs)
 
         (setenv "EXT2FS_NO_MTAB_OK" "1")
 
-        (if root-device
-            (mount-root-file-system (canonicalize-device-spec root-device)
-                                    (file-system-type root-fs)
-                                    #:volatile-root? volatile-root?
-                                    #:flags (mount-flags->bit-mask
-                                             (file-system-flags root-fs))
-                                    #:options (file-system-options root-fs)
-                                    #:check? (check? root-fs)
-                                    #:skip-check-if-clean?
-                                    (skip-check-if-clean? root-fs)
-                                    #:repair (repair root-fs))
-            (mount "none" "/root" "tmpfs"))
+        ;; Mount the root file system.
+        (mount-root-file-system (canonicalize-device-spec
+                                 (file-system-device root-fs))
+                                (file-system-type root-fs)
+                                #:volatile-root? volatile-root?
+                                #:flags (mount-flags->bit-mask
+                                         (file-system-flags root-fs))
+                                #:options (file-system-options root-fs)
+                                #:check? (check? root-fs)
+                                #:skip-check-if-clean?
+                                (skip-check-if-clean? root-fs)
+                                #:repair (repair root-fs))
 
         ;; Mount the specified non-root file systems.
         (for-each (lambda (fs)
-- 
2.34.0

bug#40998: [PATCH 1/4] system: Add a version field to the <boot-parameters> record.

[Ludovic Courtès]

Hi!

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> This version field exposes the (already present) version information of a boot
> parameters file.
>
> * gnu/system.scm (%boot-parameters-version): New variable.
> (<boot-parameters>)[version]: New field.
> (read-boot-parameters): Use it.
> (operating-system-boot-parameters-file): Likewise.
> * tests/boot-parameters.scm (test-read-boot-parameters): Use
> %boot-parameters-version as the default version value in the template.

[...]

> +  ;; New versions are not backward-compatible, so only accept past and current
> +  ;; versions, not future ones.
> +  (define (version? n)
> +    (member n (iota (1+ %boot-parameters-version))))
> +
>    (match (read port)
> -    (('boot-parameters ('version 0)
> +    (('boot-parameters ('version (? version? version))

I still have a preference for an explicit list right here, for clarity,
and so that we don’t unwillingly find ourselves treating any past
version in the same way in the future.

I think I wasn’t clear about it (sorry!) but I wonder if we could,
instead of bumping the version, use something like:

  (find (cut string-prefix? "gnu.load=") kernel-arguments)

to determine whether we’re dealing with an “old-style” “parameters”
file.

If that’s not possible, then what this patch is doing SGTM.

Thanks,
Ludo’.

bug#40998: [PATCH 2/4] system: Streamline operating-system-boot-parameters-file a bit.

[Ludovic Courtès]

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> * gnu/system.scm (operating-system-boot-parameters-file)
> [SYSTEM-KERNEL-ARGUMENTS?]: Remove unused argument (it had no callers) and
> adjust doc, moving the self-referential tip to...
> * gnu/system.scm (operating-system-boot-parameters): ... here, reworded for
> clarity.
>
> Suggested-by: Ludovic Courtès <ludo@gnu.org>

+1!

bug#40998: [PATCH 1/4] system: Add a version field to the <boot-parameters> record.

[Maxim Cournoyer]

Hi Ludovic,

Ludovic Courtès <ludo@gnu.org> writes:

> Hi!
>
> Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:
>
>> This version field exposes the (already present) version information of a boot
>> parameters file.
>>
>> * gnu/system.scm (%boot-parameters-version): New variable.
>> (<boot-parameters>)[version]: New field.
>> (read-boot-parameters): Use it.
>> (operating-system-boot-parameters-file): Likewise.
>> * tests/boot-parameters.scm (test-read-boot-parameters): Use
>> %boot-parameters-version as the default version value in the template.
>
> [...]
>
>> +  ;; New versions are not backward-compatible, so only accept past and current
>> +  ;; versions, not future ones.
>> +  (define (version? n)
>> +    (member n (iota (1+ %boot-parameters-version))))
>> +
>>    (match (read port)
>> -    (('boot-parameters ('version 0)
>> +    (('boot-parameters ('version (? version? version))
>
> I still have a preference for an explicit list right here, for clarity,
> and so that we don’t unwillingly find ourselves treating any past
> version in the same way in the future.

OK.  I prefer that we can bump %boot-parameters-version at one place and
have the rest of the code base do the right thing instead of having to
manually remember to adjust bits left and right.  I've added a comment
next to %boot-parameters-version to mention it should be incremented by
1 when bumping it.

> I think I wasn’t clear about it (sorry!) but I wonder if we could,
> instead of bumping the version, use something like:
>
>   (find (cut string-prefix? "gnu.load=") kernel-arguments)
>
> to determine whether we’re dealing with an “old-style” “parameters”
> file.
>
> If that’s not possible, then what this patch is doing SGTM.

That's not possible, because the parameters file doesn't include the
gnu.load nor gnu.system parameters because of their self-referential
nature, so we don't have such information to look at.

I'll be looking toward pushing this series today.

Thank you for the review!

Maxim

bug#40998: [PATCH 1/4] system: Add a version field to the <boot-parameters> record.

[Maxim Cournoyer]

Hi Ludovic,

Maxim Cournoyer <maxim.cournoyer@gmail.com> writes:

> Hi Ludovic,
>
> Ludovic Courtès <ludo@gnu.org> writes:
>
>> Hi!
>>
>> Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:
>>
>>> This version field exposes the (already present) version information of a boot
>>> parameters file.
>>>
>>> * gnu/system.scm (%boot-parameters-version): New variable.
>>> (<boot-parameters>)[version]: New field.
>>> (read-boot-parameters): Use it.
>>> (operating-system-boot-parameters-file): Likewise.
>>> * tests/boot-parameters.scm (test-read-boot-parameters): Use
>>> %boot-parameters-version as the default version value in the template.
>>
>> [...]
>>
>>> +  ;; New versions are not backward-compatible, so only accept past and current
>>> +  ;; versions, not future ones.
>>> +  (define (version? n)
>>> +    (member n (iota (1+ %boot-parameters-version))))
>>> +
>>>    (match (read port)
>>> -    (('boot-parameters ('version 0)
>>> +    (('boot-parameters ('version (? version? version))
>>
>> I still have a preference for an explicit list right here, for clarity,
>> and so that we don’t unwillingly find ourselves treating any past
>> version in the same way in the future.
>
> OK.  I prefer that we can bump %boot-parameters-version at one place and
> have the rest of the code base do the right thing instead of having to
> manually remember to adjust bits left and right.  I've added a comment
> next to %boot-parameters-version to mention it should be incremented by
> 1 when bumping it.
>
>> I think I wasn’t clear about it (sorry!) but I wonder if we could,
>> instead of bumping the version, use something like:
>>
>>   (find (cut string-prefix? "gnu.load=") kernel-arguments)
>>
>> to determine whether we’re dealing with an “old-style” “parameters”
>> file.
>>
>> If that’s not possible, then what this patch is doing SGTM.
>
> That's not possible, because the parameters file doesn't include the
> gnu.load nor gnu.system parameters because of their self-referential
> nature, so we don't have such information to look at.
>
> I'll be looking toward pushing this series today.

I've now pushed it as 6d9d616113cf051d80567b584a5b0a6489ddc065.  Thanks
for the review!

Maxim