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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix build vm)
#:use-module (guix build utils)
#:use-module (guix build linux-initrd)
#:use-module (guix build install)
#:use-module (ice-9 match)
#:use-module (ice-9 rdelim)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-26)
#:export (load-in-linux-vm
format-partition
initialize-root-partition
initialize-partition-table
initialize-hard-disk))
;;; Commentary:
;;;
;;; This module provides supporting code to run virtual machines and build
;;; virtual machine images using QEMU.
;;;
;;; Code:
(define (qemu-command)
"Return the default name of the QEMU command for the current host."
(string-append "qemu-system-"
(substring %host-type 0
(string-index %host-type #\-))))
(define* (load-in-linux-vm builder
#:key
output
(qemu (qemu-command)) (memory-size 512)
linux initrd
make-disk-image? (disk-image-size 100)
(disk-image-format "qcow2")
(references-graphs '()))
"Run BUILDER, a Scheme file, into a VM running LINUX with INITRD, and copy
the result to OUTPUT.
When MAKE-DISK-IMAGE? is true, OUTPUT will contain a VM image of
DISK-IMAGE-SIZE MiB resulting from the execution of BUILDER, which may access
it via /dev/hda.
REFERENCES-GRAPHS can specify a list of reference-graph files as produced by
the #:references-graphs parameter of 'derivation'."
(define image-file
(string-append "image." disk-image-format))
(when make-disk-image?
(unless (zero? (system* "qemu-img" "create" "-f" disk-image-format
image-file
(number->string disk-image-size)))
(error "qemu-img failed")))
(mkdir "xchg")
(match references-graphs
((graph-files ...)
;; Copy the reference-graph files under xchg/ so EXP can access it.
(map (lambda (file)
(copy-file file (string-append "xchg/" file)))
graph-files))
(_ #f))
(unless (zero?
(apply system* qemu "-enable-kvm" "-nographic" "-no-reboot"
"-m" (number->string memory-size)
"-net" "nic,model=virtio"
"-virtfs"
(string-append "local,id=store_dev,path="
(%store-directory)
",security_model=none,mount_tag=store")
"-virtfs"
(string-append "local,id=xchg_dev,path=xchg"
",security_model=none,mount_tag=xchg")
"-kernel" linux
"-initrd" initrd
"-append" (string-append "console=ttyS0 --load="
builder)
(if make-disk-image?
`("-drive" ,(string-append "file=" image-file
",if=virtio"))
'())))
(error "qemu failed" qemu))
(if make-disk-image?
(copy-file image-file output)
(begin
(mkdir output)
(copy-recursively "xchg" output))))
(define (read-reference-graph port)
"Return a list of store paths from the reference graph at PORT.
The data at PORT is the format produced by #:references-graphs."
(let loop ((line (read-line port))
(result '()))
(cond ((eof-object? line)
(delete-duplicates result))
((string-prefix? "/" line)
(loop (read-line port)
(cons line result)))
(else
(loop (read-line port)
result)))))
(define* (initialize-partition-table device partition-size
#:key
(label-type "msdos")
(offset (expt 2 20)))
"Create on DEVICE a partition table of type LABEL-TYPE, with a single
partition of PARTITION-SIZE bytes starting at OFFSET bytes. Return #t on
success."
(format #t "creating partition table with a ~a B partition...\n"
partition-size)
(unless (zero? (system* "parted" device "mklabel" label-type
"mkpart" "primary" "ext2"
(format #f "~aB" offset)
(format #f "~aB" partition-size)))
(error "failed to create partition table")))
(define* (populate-store reference-graphs target)
"Populate the store under directory TARGET with the items specified in
REFERENCE-GRAPHS, a list of reference-graph files."
(define store
(string-append target (%store-directory)))
(define (things-to-copy)
;; Return the list of store files to copy to the image.
(define (graph-from-file file)
(call-with-input-file file read-reference-graph))
(delete-duplicates (append-map graph-from-file reference-graphs)))
(mkdir-p store)
(chmod store #o1775)
(for-each (lambda (thing)
(copy-recursively thing
(string-append target thing)))
(things-to-copy)))
(define MS_BIND 4096) ; <sys/mounts.h> again!
(define* (format-partition partition type
#:key label)
"Create a file system TYPE on PARTITION. If LABEL is true, use that as the
volume name."
(format #t "creating ~a partition...\n" type)
(unless (zero? (apply system* (string-append "mkfs." type)
"-F" partition
(if label
`("-L" ,label)
'())))
(error "failed to create partition")))
(define* (initialize-root-partition target-directory
#:key copy-closures? register-closures?
closures)
"Initialize the root partition mounted at TARGET-DIRECTORY."
(define target-store
(string-append target-directory (%store-directory)))
(when copy-closures?
;; Populate the store.
(populate-store (map (cut string-append "/xchg/" <>) closures)
target-directory))
;; Populate /dev.
(make-essential-device-nodes #:root target-directory)
;; Optionally, register the inputs in the image's store.
(when register-closures?
(unless copy-closures?
;; XXX: 'guix-register' wants to palpate the things it registers, so
;; bind-mount the store on the target.
(mkdir-p target-store)
(mount (%store-directory) target-store "" MS_BIND))
(display "registering closures...\n")
(for-each (lambda (closure)
(register-closure target-directory
(string-append "/xchg/" closure)))
closures)
(unless copy-closures?
(system* "umount" target-store)))
;; Add the non-store directories and files.
(display "populating...\n")
(populate-root-file-system target-directory))
(define* (initialize-hard-disk device
#:key
grub.cfg
disk-image-size
(file-system-type "ext4")
file-system-label
(closures '())
copy-closures?
(register-closures? #t))
"Initialize DEVICE, a disk of DISK-IMAGE-SIZE bytes, with a FILE-SYSTEM-TYPE
partition with (optionally) FILE-SYSTEM-LABEL as its volume name, and with
GRUB installed. If REGISTER-CLOSURES? is true, register all of CLOSURES is
the partition's store. If COPY-CLOSURES? is true, copy all of CLOSURES to the
partition."
(define target-directory
"/fs")
(define partition
(string-append device "1"))
(initialize-partition-table device
(- disk-image-size (* 5 (expt 2 20))))
(format-partition partition file-system-type
#:label file-system-label)
(display "mounting partition...\n")
(mkdir target-directory)
(mount partition target-directory file-system-type)
(initialize-root-partition target-directory
#:copy-closures? copy-closures?
#:register-closures? register-closures?
#:closures closures)
(install-grub grub.cfg device target-directory)
;; 'guix-register' resets timestamps and everything, so no need to do it
;; once more in that case.
(unless register-closures?
(reset-timestamps target-directory))
(zero? (system* "umount" target-directory)))
;;; vm.scm ends here
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