summary refs log tree commit diff
path: root/gnu/build/vm.scm
blob: 03db1cd5f92b41b9b2df17b45070294cc315bb8a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
;;; 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 (gnu build vm)
  #:use-module (guix build utils)
  #:use-module (guix build store-copy)
  #:use-module (gnu build linux-boot)
  #:use-module (gnu build install)
  #:use-module (ice-9 match)
  #:use-module (ice-9 regex)
  #:use-module (srfi srfi-26)
  #:export (qemu-command
            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 #:optional (system %host-type))
  "Return the default name of the QEMU command for SYSTEM."
  (let ((cpu (substring %host-type 0
                        (string-index %host-type #\-))))
    (string-append "qemu-system-"
                   (if (string-match "^i[3456]86$" cpu)
                       "i386"
                       cpu))))

(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* (initialize-partition-table device partition-size
                                     #:key
                                     bootable?
                                     (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.  When BOOTABLE? is
true, set the bootable flag on the partition.  Return #t on success."
  (format #t "creating partition table with a ~a B partition...\n"
          partition-size)
  (unless (zero? (apply system* "parted" device "mklabel" label-type
                        "mkpart" "primary" "ext2"
                        (format #f "~aB" offset)
                        (format #f "~aB" partition-size)
                        (if bootable?
                            '("set" "1" "boot" "on")
                            '())))
    (error "failed to create partition table")))

(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 system-directory)
  "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 system-directory target-directory))

(define* (initialize-hard-disk device
                               #:key
                               system-directory
                               grub.cfg
                               disk-image-size
                               (file-system-type "ext4")
                               file-system-label
                               (closures '())
                               copy-closures?
                               (bootable? #t)
                               (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.  When BOOTABLE? is true, set the bootable flag on that
partition.

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.
SYSTEM-DIRECTORY is the name of the directory of the 'system' derivation."
  (define target-directory
    "/fs")

  (define partition
    (string-append device "1"))

  (initialize-partition-table device
                              (- disk-image-size (* 5 (expt 2 20)))
                              #:bootable? bootable?)

  (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
                             #:system-directory system-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