1 files changed, 34 insertions, 0 deletions

diff --git a/gnu/bootloader/grub.scm b/gnu/bootloader/grub.scm
index 120cd55012b..65d7171432c 100644
--- a/gnu/bootloader/grub.scm
+++ b/gnu/bootloader/grub.scm
@@ -7,6 +7,7 @@
 ;;; Copyright © 2019, 2020 Miguel Ángel Arruga Vivas <rosen644835@gmail.com>
 ;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com>
 ;;; Copyright © 2020 Stefan <stefan-guix@vodafonemail.de>
+;;; Copyright © 2022 Karl Hallsby <karl@hallsby.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -50,10 +51,12 @@
             grub-theme-color-highlight
             grub-theme-gfxmode
 
+            install-grub-efi-removable
             install-grub-efi-netboot
 
             grub-bootloader
             grub-efi-bootloader
+            grub-efi-removable-bootloader
             grub-efi-netboot-bootloader
             grub-mkrescue-bootloader
             grub-minimal-bootloader
@@ -608,6 +611,31 @@ fi~%"))))
                         "--bootloader-id=Guix"
                         "--efi-directory" target-esp)))))
 
+(define install-grub-efi-removable
+  #~(lambda (bootloader efi-dir mount-point)
+      ;; NOTE: mount-point is /mnt in guix system init /etc/config.scm /mnt/point
+      ;; NOTE: efi-dir comes from target list of booloader configuration
+      ;; There is nothing useful to do when called in the context of a disk
+      ;; image generation.
+      (when efi-dir
+        ;; Install GRUB onto the EFI partition mounted at EFI-DIR, for the
+        ;; system whose root is mounted at MOUNT-POINT.
+        (let ((grub-install (string-append bootloader "/sbin/grub-install"))
+              (install-dir (string-append mount-point "/boot"))
+              ;; When installing Guix, it's common to mount EFI-DIR below
+              ;; MOUNT-POINT rather than /boot/efi on the live image.
+              (target-esp (if (file-exists? (string-append mount-point efi-dir))
+                              (string-append mount-point efi-dir)
+                              efi-dir)))
+          ;; Tell 'grub-install' that there might be a LUKS-encrypted /boot or
+          ;; root partition.
+          (setenv "GRUB_ENABLE_CRYPTODISK" "y")
+          (invoke/quiet grub-install "--boot-directory" install-dir
+                        "--removable"
+                        ;; "--no-nvram"
+                        "--bootloader-id=Guix"
+                        "--efi-directory" target-esp)))))
+
 (define (install-grub-efi-netboot subdir)
   "Define a grub-efi-netboot bootloader installer for installation in SUBDIR,
 which is usually efi/Guix or efi/boot."
@@ -734,6 +762,12 @@ considered for security aspects."
    (name 'grub-efi)
    (package grub-efi)))
 
+(define grub-efi-removable-bootloader
+  (bootloader
+   (inherit grub-efi-bootloader)
+   (name 'grub-efi-removable-bootloader)
+   (installer install-grub-efi-removable)))
+
 (define grub-efi-netboot-bootloader
   (bootloader
    (inherit grub-efi-bootloader)