gnu/system/vm.scm

   1 ;;; GNU Guix --- Functional package management for GNU
   2 ;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
   3 ;;; Copyright © 2016 Christopher Allan Webber <cwebber@dustycloud.org>
   4 ;;; Copyright © 2016, 2017 Leo Famulari <leo@famulari.name>
   5 ;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
   6 ;;; Copyright © 2017 Marius Bakke <mbakke@fastmail.com>
   7 ;;; Copyright © 2018 Chris Marusich <cmmarusich@gmail.com>
   8 ;;;
   9 ;;; This file is part of GNU Guix.
  10 ;;;
  11 ;;; GNU Guix is free software; you can redistribute it and/or modify it
  12 ;;; under the terms of the GNU General Public License as published by
  13 ;;; the Free Software Foundation; either version 3 of the License, or (at
  14 ;;; your option) any later version.
  15 ;;;
  16 ;;; GNU Guix is distributed in the hope that it will be useful, but
  17 ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;;; GNU General Public License for more details.
  20 ;;;
  21 ;;; You should have received a copy of the GNU General Public License
  22 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 (define-module (gnu system vm)
  25   #:use-module (guix config)
  26   #:use-module (guix store)
  27   #:use-module (guix gexp)
  28   #:use-module (guix derivations)
  29   #:use-module (guix packages)
  30   #:use-module (guix monads)
  31   #:use-module (guix records)
  32   #:use-module (guix modules)
  33   #:use-module (guix utils)
  34   #:use-module (gcrypt hash)
  35   #:use-module (guix base32)
  36   #:use-module ((guix self) #:select (make-config.scm))
  37
  38   #:use-module ((gnu build vm)
  39                 #:select (qemu-command))
  40   #:use-module (gnu packages base)
  41   #:use-module (gnu packages bootloaders)
  42   #:use-module (gnu packages cdrom)
  43   #:use-module (gnu packages compression)
  44   #:use-module (gnu packages guile)
  45   #:autoload   (gnu packages gnupg) (guile-gcrypt)
  46   #:use-module (gnu packages gawk)
  47   #:use-module (gnu packages bash)
  48   #:use-module (gnu packages less)
  49   #:use-module (gnu packages virtualization)
  50   #:use-module (gnu packages disk)
  51   #:use-module (gnu packages zile)
  52   #:use-module (gnu packages linux)
  53   #:use-module ((gnu packages make-bootstrap)
  54                 #:select (%guile-static-stripped))
  55   #:use-module (gnu packages admin)
  56
  57   #:use-module (gnu bootloader)
  58   #:use-module (gnu bootloader grub)
  59   #:use-module (gnu system shadow)
  60   #:use-module (gnu system pam)
  61   #:use-module (gnu system linux-container)
  62   #:use-module (gnu system linux-initrd)
  63   #:use-module (gnu bootloader)
  64   #:use-module (gnu system file-systems)
  65   #:use-module (gnu system)
  66   #:use-module (gnu services)
  67   #:use-module (gnu services base)
  68   #:use-module (gnu system uuid)
  69
  70   #:use-module (srfi srfi-1)
  71   #:use-module (srfi srfi-26)
  72   #:use-module (rnrs bytevectors)
  73   #:use-module (ice-9 match)
  74
  75   #:export (expression->derivation-in-linux-vm
  76             qemu-image
  77             virtualized-operating-system
  78             system-qemu-image
  79
  80             system-qemu-image/shared-store
  81             system-qemu-image/shared-store-script
  82             system-disk-image
  83             system-docker-image
  84
  85             virtual-machine
  86             virtual-machine?))
  87
  88 \f
  89 ;;; Commentary:
  90 ;;;
  91 ;;; Tools to evaluate build expressions within virtual machines.
  92 ;;;
  93 ;;; Code:
  94
  95 (define %linux-vm-file-systems
  96   ;; File systems mounted for 'derivation-in-linux-vm'.  These are shared with
  97   ;; the host over 9p.
  98   ;;
  99   ;; The 9p documentation says that cache=loose is "intended for exclusive,
 100   ;; read-only mounts", without additional details.  It's much faster than the
 101   ;; default cache=none, especially when copying and registering store items.
 102   ;; Thus, use cache=loose, except for /xchg where we want to ensure
 103   ;; consistency.
 104   (list (file-system
 105           (mount-point (%store-prefix))
 106           (device "store")
 107           (type "9p")
 108           (needed-for-boot? #t)
 109           (flags '(read-only))
 110           (options "trans=virtio,cache=loose")
 111           (check? #f))
 112         (file-system
 113           (mount-point "/xchg")
 114           (device "xchg")
 115           (type "9p")
 116           (needed-for-boot? #t)
 117           (options "trans=virtio")
 118           (check? #f))
 119         (file-system
 120           (mount-point "/tmp")
 121           (device "tmp")
 122           (type "9p")
 123           (needed-for-boot? #t)
 124           (options "trans=virtio,cache=loose")
 125           (check? #f))))
 126
 127 (define not-config?
 128   ;; Select (guix …) and (gnu …) modules, except (guix config).
 129   (match-lambda
 130     (('guix 'config) #f)
 131     (('guix rest ...) #t)
 132     (('gnu rest ...) #t)
 133     (rest #f)))
 134
 135 (define gcrypt-sqlite3&co
 136   ;; Guile-Gcrypt, Guile-SQLite3, and their propagated inputs.
 137   (append-map (lambda (package)
 138                 (cons package
 139                       (match (package-transitive-propagated-inputs package)
 140                         (((labels packages) ...)
 141                          packages))))
 142               (list guile-gcrypt guile-sqlite3)))
 143
 144 (define* (expression->derivation-in-linux-vm name exp
 145                                              #:key
 146                                              (system (%current-system)) target
 147                                              (linux linux-libre)
 148                                              initrd
 149                                              (qemu qemu-minimal)
 150                                              (env-vars '())
 151                                              (guile-for-build
 152                                               (%guile-for-build))
 153                                              (file-systems
 154                                               %linux-vm-file-systems)
 155
 156                                              (single-file-output? #f)
 157                                              (make-disk-image? #f)
 158                                              (references-graphs #f)
 159                                              (memory-size 256)
 160                                              (disk-image-format "qcow2")
 161                                              (disk-image-size 'guess)
 162
 163                                              (substitutable? #t))
 164   "Evaluate EXP in a QEMU virtual machine running LINUX with INITRD (a
 165 derivation).  The virtual machine runs with MEMORY-SIZE MiB of memory.  In the
 166 virtual machine, EXP has access to FILE-SYSTEMS, which, by default, includes a
 167 9p share of the store, the '/xchg' where EXP should put its output file(s),
 168 and a 9p share of /tmp.
 169
 170 If SINGLE-FILE-OUTPUT? is true, copy a single file from '/xchg' to OUTPUT.
 171 Otherwise, copy the contents of /xchg to a new directory OUTPUT.
 172
 173 When MAKE-DISK-IMAGE? is true, then create a QEMU disk image of type
 174 DISK-IMAGE-FORMAT (e.g., 'qcow2' or 'raw'), of DISK-IMAGE-SIZE bytes and
 175 return it.  When DISK-IMAGE-SIZE is 'guess, estimate the image size based
 176 based on the size of the closure of REFERENCES-GRAPHS.
 177
 178 When REFERENCES-GRAPHS is true, it must be a list of file name/store path
 179 pairs, as for `derivation'.  The files containing the reference graphs are
 180 made available under the /xchg CIFS share.
 181
 182 SUBSTITUTABLE? determines whether the returned derivation should be marked as
 183 substitutable."
 184   (define user-builder
 185     (program-file "builder-in-linux-vm" exp))
 186
 187   (define loader
 188     ;; Invoke USER-BUILDER instead using 'primitive-load'.  The reason for
 189     ;; this is to allow USER-BUILDER to dlopen stuff by using a full-featured
 190     ;; Guile, which it couldn't do using the statically-linked guile used in
 191     ;; the initrd.  See example at
 192     ;; <https://lists.gnu.org/archive/html/guix-devel/2017-10/msg00233.html>.
 193     (program-file "linux-vm-loader"
 194                   ;; Communicate USER-BUILDER's exit status via /xchg so that
 195                   ;; the host can distinguish between success, failure, and
 196                   ;; kernel panic.
 197                   #~(let ((status (system* #$user-builder)))
 198                       (call-with-output-file "/xchg/.exit-status"
 199                         (lambda (port)
 200                           (write status port)))
 201                       (sync)
 202                       (reboot))))
 203
 204   (let ((initrd (or initrd
 205                     (base-initrd file-systems
 206                                  #:on-error 'backtrace
 207                                  #:linux linux
 208                                  #:linux-modules %base-initrd-modules
 209                                  #:qemu-networking? #t))))
 210
 211     (define builder
 212       ;; Code that launches the VM that evaluates EXP.
 213       (with-extensions gcrypt-sqlite3&co
 214         (with-imported-modules `(,@(source-module-closure
 215                                     '((guix build utils)
 216                                       (gnu build vm))
 217                                     #:select? not-config?)
 218
 219                                  ;; For consumption by (gnu store database).
 220                                  ((guix config) => ,(make-config.scm)))
 221           #~(begin
 222               (use-modules (guix build utils)
 223                            (gnu build vm))
 224
 225               (let* ((native-inputs
 226                       '#+(list qemu (canonical-package coreutils)))
 227                      (linux   (string-append #$linux "/"
 228                                              #$(system-linux-image-file-name)))
 229                      (initrd  #$initrd)
 230                      (loader  #$loader)
 231                      (graphs  '#$(match references-graphs
 232                                    (((graph-files . _) ...) graph-files)
 233                                    (_ #f)))
 234                      (target  #$(or (%current-target-system) (%current-system)))
 235                      (size    #$(if (eq? 'guess disk-image-size)
 236                                     #~(+ (* 70 (expt 2 20)) ;ESP
 237                                          (estimated-partition-size graphs))
 238                                     disk-image-size)))
 239
 240                 (set-path-environment-variable "PATH" '("bin") native-inputs)
 241
 242                 (load-in-linux-vm loader
 243                                   #:output #$output
 244                                   #:linux linux #:initrd initrd
 245                                   #:qemu (qemu-command target)
 246                                   #:memory-size #$memory-size
 247                                   #:make-disk-image? #$make-disk-image?
 248                                   #:single-file-output? #$single-file-output?
 249                                   ;; FIXME: ‘target-arm32?’ and
 250                                   ;; ‘target-aarch64?’ may not operate on the
 251                                   ;; right system/target values.  Rewrite
 252                                   ;; using ‘let-system’ when available.
 253                                   #:target-arm32? #$(target-arm32?)
 254                                   #:target-aarch64? #$(target-aarch64?)
 255                                   #:disk-image-format #$disk-image-format
 256                                   #:disk-image-size size
 257                                   #:references-graphs graphs))))))
 258
 259     (gexp->derivation name builder
 260                       ;; TODO: Require the "kvm" feature.
 261                       #:system system
 262                       #:target target
 263                       #:env-vars env-vars
 264                       #:guile-for-build guile-for-build
 265                       #:references-graphs references-graphs
 266                       #:substitutable? substitutable?)))
 267
 268 (define (has-guix-service-type? os)
 269   "Return true if OS contains a service of the type GUIX-SERVICE-TYPE."
 270   (not (not (find (lambda (service)
 271                      (eq? (service-kind service) guix-service-type))
 272                    (operating-system-services os)))))
 273
 274 (define* (iso9660-image #:key
 275                         (name "iso9660-image")
 276                         file-system-label
 277                         file-system-uuid
 278                         (system (%current-system))
 279                         (target (%current-target-system))
 280                         (qemu qemu-minimal)
 281                         os
 282                         bootcfg-drv
 283                         bootloader
 284                         (register-closures? (has-guix-service-type? os))
 285                         (inputs '())
 286                         (grub-mkrescue-environment '())
 287                         (substitutable? #t))
 288   "Return a bootable, stand-alone iso9660 image.
 289
 290 INPUTS is a list of inputs (as for packages)."
 291   (define schema
 292     (and register-closures?
 293          (local-file (search-path %load-path
 294                                   "guix/store/schema.sql"))))
 295
 296   (expression->derivation-in-linux-vm
 297    name
 298    (with-extensions gcrypt-sqlite3&co
 299      (with-imported-modules `(,@(source-module-closure '((gnu build vm)
 300                                                          (guix store database)
 301                                                          (guix build utils))
 302                                                        #:select? not-config?)
 303                               ((guix config) => ,(make-config.scm)))
 304        #~(begin
 305            (use-modules (gnu build vm)
 306                         (guix store database)
 307                         (guix build utils))
 308
 309            (sql-schema #$schema)
 310
 311            ;; Allow non-ASCII file names--e.g., 'nss-certs'--to be decoded.
 312            (setenv "GUIX_LOCPATH"
 313                    #+(file-append glibc-utf8-locales "/lib/locale"))
 314            (setlocale LC_ALL "en_US.utf8")
 315
 316            (let ((inputs
 317                   '#$(append (list parted e2fsprogs dosfstools xorriso)
 318                              (map canonical-package
 319                                   (list sed grep coreutils findutils gawk))))
 320
 321
 322                  (graphs     '#$(match inputs
 323                                   (((names . _) ...)
 324                                    names)))
 325                  ;; This variable is unused but allows us to add INPUTS-TO-COPY
 326                  ;; as inputs.
 327                  (to-register
 328                   '#$(map (match-lambda
 329                             ((name thing) thing)
 330                             ((name thing output) `(,thing ,output)))
 331                           inputs)))
 332
 333              (set-path-environment-variable "PATH" '("bin" "sbin") inputs)
 334              (make-iso9660-image #$xorriso
 335                                  '#$grub-mkrescue-environment
 336                                  #$(bootloader-package bootloader)
 337                                  #$bootcfg-drv
 338                                  #$os
 339                                  "/xchg/guixsd.iso"
 340                                  #:register-closures? #$register-closures?
 341                                  #:closures graphs
 342                                  #:volume-id #$file-system-label
 343                                  #:volume-uuid #$(and=> file-system-uuid
 344                                                         uuid-bytevector))))))
 345    #:system system
 346    #:target target
 347
 348    ;; Keep a local file system for /tmp so that we can populate it directly as
 349    ;; root and have files owned by root.  See <https://bugs.gnu.org/31752>.
 350    #:file-systems (remove (lambda (file-system)
 351                             (string=? (file-system-mount-point file-system)
 352                                       "/tmp"))
 353                           %linux-vm-file-systems)
 354
 355    #:make-disk-image? #f
 356    #:single-file-output? #t
 357    #:references-graphs inputs
 358    #:substitutable? substitutable?
 359
 360    ;; Xorriso seems to be quite memory-hungry, so increase the VM's RAM size.
 361    #:memory-size 512))
 362
 363 (define* (qemu-image #:key
 364                      (name "qemu-image")
 365                      (system (%current-system))
 366                      (target (%current-target-system))
 367                      (qemu qemu-minimal)
 368                      (disk-image-size 'guess)
 369                      (disk-image-format "qcow2")
 370                      (file-system-type "ext4")
 371                      file-system-label
 372                      file-system-uuid
 373                      os
 374                      bootcfg-drv
 375                      bootloader
 376                      (register-closures? (has-guix-service-type? os))
 377                      (inputs '())
 378                      copy-inputs?
 379                      (substitutable? #t))
 380   "Return a bootable, stand-alone QEMU image of type DISK-IMAGE-FORMAT (e.g.,
 381 'qcow2' or 'raw'), with a root partition of type FILE-SYSTEM-TYPE.
 382 Optionally, FILE-SYSTEM-LABEL can be specified as the volume name for the root
 383 partition; likewise FILE-SYSTEM-UUID, if true, specifies the UUID of the root
 384 partition (a UUID object).
 385
 386 The returned image is a full disk image that runs OS-DERIVATION,
 387 with a GRUB installation that uses GRUB-CONFIGURATION as its configuration
 388 file (GRUB-CONFIGURATION must be the name of a file in the VM.)
 389
 390 INPUTS is a list of inputs (as for packages).  When COPY-INPUTS? is true, copy
 391 all of INPUTS into the image being built.  When REGISTER-CLOSURES? is true,
 392 register INPUTS in the store database of the image so that Guix can be used in
 393 the image.  By default, REGISTER-CLOSURES? is set to true only if a service of
 394 type GUIX-SERVICE-TYPE is present in the services definition of the operating
 395 system."
 396   (define schema
 397     (and register-closures?
 398          (local-file (search-path %load-path
 399                                   "guix/store/schema.sql"))))
 400
 401   (expression->derivation-in-linux-vm
 402    name
 403    (with-extensions gcrypt-sqlite3&co
 404      (with-imported-modules `(,@(source-module-closure '((gnu build vm)
 405                                                          (gnu build bootloader)
 406                                                          (guix store database)
 407                                                          (guix build utils))
 408                                                        #:select? not-config?)
 409                               ((guix config) => ,(make-config.scm)))
 410        #~(begin
 411            (use-modules (gnu build bootloader)
 412                         (gnu build vm)
 413                         (guix store database)
 414                         (guix build utils)
 415                         (srfi srfi-26)
 416                         (ice-9 binary-ports))
 417
 418            (sql-schema #$schema)
 419
 420            ;; Allow non-ASCII file names--e.g., 'nss-certs'--to be decoded.
 421            (setenv "GUIX_LOCPATH"
 422                    #+(file-append glibc-utf8-locales "/lib/locale"))
 423            (setlocale LC_ALL "en_US.utf8")
 424
 425            (let ((inputs
 426                   '#$(append (list parted e2fsprogs dosfstools)
 427                              (map canonical-package
 428                                   (list sed grep coreutils findutils gawk))))
 429
 430                  ;; This variable is unused but allows us to add INPUTS-TO-COPY
 431                  ;; as inputs.
 432                  (to-register
 433                   '#$(map (match-lambda
 434                             ((name thing) thing)
 435                             ((name thing output) `(,thing ,output)))
 436                           inputs)))
 437
 438              (set-path-environment-variable "PATH" '("bin" "sbin") inputs)
 439
 440              (let* ((graphs     '#$(match inputs
 441                                      (((names . _) ...)
 442                                       names)))
 443                     (initialize (root-partition-initializer
 444                                  #:closures graphs
 445                                  #:copy-closures? #$copy-inputs?
 446                                  #:register-closures? #$register-closures?
 447                                  #:system-directory #$os
 448
 449                                  ;; Disable deduplication to speed things up,
 450                                  ;; and because it doesn't help much for a
 451                                  ;; single system generation.
 452                                  #:deduplicate? #f))
 453                     (root-size  #$(if (eq? 'guess disk-image-size)
 454                                       #~(max
 455                                          ;; Minimum 20 MiB root size
 456                                          (* 20 (expt 2 20))
 457                                          (estimated-partition-size
 458                                           (map (cut string-append "/xchg/" <>)
 459                                                graphs)))
 460                                       (- disk-image-size
 461                                          (* 50 (expt 2 20)))))
 462                     (partitions
 463                      (append
 464                       (list (partition
 465                              (size root-size)
 466                              (label #$file-system-label)
 467                              (uuid #$(and=> file-system-uuid
 468                                             uuid-bytevector))
 469                              (file-system #$file-system-type)
 470                              (flags '(boot))
 471                              (initializer initialize)))
 472                       ;; Append a small EFI System Partition for use with UEFI
 473                       ;; bootloaders if we are not targeting ARM because UEFI
 474                       ;; support in U-Boot is experimental.
 475                       ;;
 476                       ;; FIXME: ‘target-arm?’ may be not operate on the right
 477                       ;; system/target values.  Rewrite using ‘let-system’ when
 478                       ;; available.
 479                       (if #$(target-arm?)
 480                           '()
 481                           (list (partition
 482                                  ;; The standalone grub image is about 10MiB, but
 483                                  ;; leave some room for custom or multiple images.
 484                                  (size (* 40 (expt 2 20)))
 485                                  (label "GNU-ESP") ;cosmetic only
 486                                  ;; Use "vfat" here since this property is used
 487                                  ;; when mounting. The actual FAT-ness is based
 488                                  ;; on file system size (16 in this case).
 489                                  (file-system "vfat")
 490                                  (flags '(esp)))))))
 491                     (grub-efi #$(and (not (target-arm?)) grub-efi)))
 492                (initialize-hard-disk "/dev/vda"
 493                                      #:partitions partitions
 494                                      #:grub-efi grub-efi
 495                                      #:bootloader-package
 496                                      #$(bootloader-package bootloader)
 497                                      #:bootcfg #$bootcfg-drv
 498                                      #:bootcfg-location
 499                                      #$(bootloader-configuration-file bootloader)
 500                                      #:bootloader-installer
 501                                      #$(bootloader-installer bootloader)))))))
 502    #:system system
 503    #:target target
 504    #:make-disk-image? #t
 505    #:disk-image-size disk-image-size
 506    #:disk-image-format disk-image-format
 507    #:references-graphs inputs
 508    #:substitutable? substitutable?))
 509
 510 (define* (system-docker-image os
 511                               #:key
 512                               (name "guix-docker-image")
 513                               (register-closures? (has-guix-service-type? os)))
 514   "Build a docker image.  OS is the desired <operating-system>.  NAME is the
 515 base name to use for the output file.  When REGISTER-CLOSURES? is true,
 516 register the closure of OS with Guix in the resulting Docker image.  By
 517 default, REGISTER-CLOSURES? is set to true only if a service of type
 518 GUIX-SERVICE-TYPE is present in the services definition of the operating
 519 system."
 520   (define schema
 521     (and register-closures?
 522          (local-file (search-path %load-path
 523                                   "guix/store/schema.sql"))))
 524
 525   (define boot-program
 526     ;; Program that runs the boot script of OS, which in turn starts shepherd.
 527     (program-file "boot-program"
 528                   #~(let ((system (cadr (command-line))))
 529                       (setenv "GUIX_NEW_SYSTEM" system)
 530                       (execl #$(file-append guile-2.2 "/bin/guile")
 531                              "guile" "--no-auto-compile"
 532                              (string-append system "/boot")))))
 533
 534
 535   (let ((os    (operating-system-with-gc-roots
 536                 (containerized-operating-system os '())
 537                 (list boot-program)))
 538         (name  (string-append name ".tar.gz"))
 539         (graph "system-graph"))
 540     (define build
 541       (with-extensions (cons guile-json-3         ;for (guix docker)
 542                              gcrypt-sqlite3&co)   ;for (guix store database)
 543         (with-imported-modules `(,@(source-module-closure
 544                                     '((guix docker)
 545                                       (guix store database)
 546                                       (guix build utils)
 547                                       (guix build store-copy)
 548                                       (gnu build vm))
 549                                     #:select? not-config?)
 550                                  ((guix config) => ,(make-config.scm)))
 551           #~(begin
 552               (use-modules (guix docker)
 553                            (guix build utils)
 554                            (gnu build vm)
 555                            (srfi srfi-19)
 556                            (guix build store-copy)
 557                            (guix store database))
 558
 559               ;; Set the SQL schema location.
 560               (sql-schema #$schema)
 561
 562               ;; Allow non-ASCII file names--e.g., 'nss-certs'--to be decoded.
 563               (setenv "GUIX_LOCPATH"
 564                       #+(file-append glibc-utf8-locales "/lib/locale"))
 565               (setlocale LC_ALL "en_US.utf8")
 566
 567               (let* (;; This initializer requires elevated privileges that are
 568                      ;; not normally available in the build environment (e.g.,
 569                      ;; it needs to create device nodes).  In order to obtain
 570                      ;; such privileges, we run it as root in a VM.
 571                      (initialize (root-partition-initializer
 572                                   #:closures '(#$graph)
 573                                   #:register-closures? #$register-closures?
 574                                   #:system-directory #$os
 575                                   ;; De-duplication would fail due to
 576                                   ;; cross-device link errors, so don't do it.
 577                                   #:deduplicate? #f))
 578                      ;; Even as root in a VM, the initializer would fail due to
 579                      ;; lack of privileges if we use a root-directory that is on
 580                      ;; a file system that is shared with the host (e.g., /tmp).
 581                      (root-directory "/guixsd-system-root"))
 582                 (set-path-environment-variable "PATH" '("bin" "sbin") '(#+tar))
 583                 (mkdir root-directory)
 584                 (initialize root-directory)
 585                 (build-docker-image
 586                  (string-append "/xchg/" #$name) ;; The output file.
 587                  (cons* root-directory
 588                         (map store-info-item
 589                              (call-with-input-file
 590                                  (string-append "/xchg/" #$graph)
 591                                read-reference-graph)))
 592                  #$os
 593                  #:entry-point '(#$boot-program #$os)
 594                  #:compressor '(#+(file-append gzip "/bin/gzip") "-9n")
 595                  #:creation-time (make-time time-utc 0 1)
 596                  #:transformations `((,root-directory -> ""))))))))
 597
 598     (expression->derivation-in-linux-vm
 599      name build
 600      #:make-disk-image? #f
 601      #:single-file-output? #t
 602      #:references-graphs `((,graph ,os)))))
 603
 604 \f
 605 ;;;
 606 ;;; VM and disk images.
 607 ;;;
 608
 609 (define* (operating-system-uuid os #:optional (type 'dce))
 610   "Compute UUID object with a deterministic \"UUID\" for OS, of the given
 611 TYPE (one of 'iso9660 or 'dce).  Return a UUID object."
 612   ;; Note: For this to be deterministic, we must not hash things that contains
 613   ;; (directly or indirectly) procedures, for example.  That rules out
 614   ;; anything that contains gexps, thunk or delayed record fields, etc.
 615
 616   (define service-name
 617     (compose service-type-name service-kind))
 618
 619   (define (file-system-digest fs)
 620     ;; Return a hashable digest that does not contain 'dependencies' since
 621     ;; this field can contain procedures.
 622     (let ((device (file-system-device fs)))
 623       (list (file-system-mount-point fs)
 624             (file-system-type fs)
 625             (file-system-device->string device)
 626             (file-system-options fs))))
 627
 628   (if (eq? type 'iso9660)
 629       (let ((pad (compose (cut string-pad <> 2 #\0)
 630                           number->string))
 631             (h   (hash (map service-name (operating-system-services os))
 632                        3600)))
 633         (bytevector->uuid
 634          (string->iso9660-uuid
 635           (string-append "1970-01-01-"
 636                          (pad (hash (operating-system-host-name os) 24)) "-"
 637                          (pad (quotient h 60)) "-"
 638                          (pad (modulo h 60)) "-"
 639                          (pad (hash (map file-system-digest
 640                                          (operating-system-file-systems os))
 641                                     100))))
 642          'iso9660))
 643       (bytevector->uuid
 644        (uint-list->bytevector
 645         (list (hash (map file-system-digest
 646                          (operating-system-file-systems os))
 647                     (- (expt 2 32) 1))
 648               (hash (operating-system-host-name os)
 649                     (- (expt 2 32) 1))
 650               (hash (map service-name (operating-system-services os))
 651                     (- (expt 2 32) 1))
 652               (hash (map file-system-digest (operating-system-file-systems os))
 653                     (- (expt 2 32) 1)))
 654         (endianness little)
 655         4)
 656        type)))
 657
 658 (define* (system-disk-image os
 659                             #:key
 660                             (name "disk-image")
 661                             (file-system-type "ext4")
 662                             (disk-image-size (* 900 (expt 2 20)))
 663                             (volatile? #t)
 664                             (substitutable? #t))
 665   "Return the derivation of a disk image of DISK-IMAGE-SIZE bytes of the
 666 system described by OS.  Said image can be copied on a USB stick as is.  When
 667 VOLATILE? is true, the root file system is made volatile; this is useful
 668 to USB sticks meant to be read-only.
 669
 670 SUBSTITUTABLE? determines whether the returned derivation should be marked as
 671 substitutable."
 672   (define normalize-label
 673     ;; ISO labels are all-caps (case-insensitive), but since
 674     ;; 'find-partition-by-label' is case-sensitive, make it all-caps here.
 675     (if (string=? "iso9660" file-system-type)
 676         string-upcase
 677         identity))
 678
 679   (define root-label
 680     ;; Volume name of the root file system.
 681     (normalize-label "Guix_image"))
 682
 683   (define (root-uuid os)
 684     ;; UUID of the root file system, computed in a deterministic fashion.
 685     ;; This is what we use to locate the root file system so it has to be
 686     ;; different from the user's own file system UUIDs.
 687     (operating-system-uuid os
 688                            (if (string=? file-system-type "iso9660")
 689                                'iso9660
 690                                'dce)))
 691
 692   (define file-systems-to-keep
 693     (remove (lambda (fs)
 694               (string=? (file-system-mount-point fs) "/"))
 695             (operating-system-file-systems os)))
 696
 697   (let* ((os (operating-system (inherit os)
 698                ;; Since this is meant to be used on real hardware, don't
 699                ;; install QEMU networking or anything like that.  Assume USB
 700                ;; mass storage devices (usb-storage.ko) are available.
 701                (initrd (lambda (file-systems . rest)
 702                          (apply (operating-system-initrd os)
 703                                 file-systems
 704                                 #:volatile-root? volatile?
 705                                 rest)))
 706
 707                (bootloader (if (string=? "iso9660" file-system-type)
 708                                (bootloader-configuration
 709                                  (inherit (operating-system-bootloader os))
 710                                  (bootloader grub-mkrescue-bootloader))
 711                                (operating-system-bootloader os)))
 712
 713                ;; Force our own root file system.  (We need a "/" file system
 714                ;; to call 'root-uuid'.)
 715                (file-systems (cons (file-system
 716                                      (mount-point "/")
 717                                      (device "/dev/placeholder")
 718                                      (type file-system-type))
 719                                    file-systems-to-keep))))
 720          (uuid (root-uuid os))
 721          (os (operating-system
 722                (inherit os)
 723                (file-systems (cons (file-system
 724                                      (mount-point "/")
 725                                      (device uuid)
 726                                      (type file-system-type))
 727                                    file-systems-to-keep))))
 728         (bootcfg (operating-system-bootcfg os)))
 729     (if (string=? "iso9660" file-system-type)
 730         (iso9660-image #:name name
 731                        #:file-system-label root-label
 732                        #:file-system-uuid uuid
 733                        #:os os
 734                        #:bootcfg-drv bootcfg
 735                        #:bootloader (bootloader-configuration-bootloader
 736                                      (operating-system-bootloader os))
 737                        #:inputs `(("system" ,os)
 738                                   ("bootcfg" ,bootcfg))
 739                        #:grub-mkrescue-environment
 740                        '(("MKRESCUE_SED_MODE" . "mbr_hfs"))
 741                        #:substitutable? substitutable?)
 742         (qemu-image #:name name
 743                     #:os os
 744                     #:bootcfg-drv bootcfg
 745                     #:bootloader (bootloader-configuration-bootloader
 746                                   (operating-system-bootloader os))
 747                     #:disk-image-size disk-image-size
 748                     #:disk-image-format "raw"
 749                     #:file-system-type file-system-type
 750                     #:file-system-label root-label
 751                     #:file-system-uuid uuid
 752                     #:copy-inputs? #t
 753                     #:inputs `(("system" ,os)
 754                                ("bootcfg" ,bootcfg))
 755                     #:substitutable? substitutable?))))
 756
 757 (define* (system-qemu-image os
 758                             #:key
 759                             (file-system-type "ext4")
 760                             (disk-image-size (* 900 (expt 2 20))))
 761   "Return the derivation of a freestanding QEMU image of DISK-IMAGE-SIZE bytes
 762 of the GNU system as described by OS."
 763   (define file-systems-to-keep
 764     ;; Keep only file systems other than root and not normally bound to real
 765     ;; devices.
 766     (remove (lambda (fs)
 767               (let ((target (file-system-mount-point fs))
 768                     (source (file-system-device fs)))
 769                 (or (string=? target "/")
 770                     (string-prefix? "/dev/" source))))
 771             (operating-system-file-systems os)))
 772
 773   (define root-uuid
 774     ;; UUID of the root file system.
 775     (operating-system-uuid os
 776                            (if (string=? file-system-type "iso9660")
 777                                'iso9660
 778                                'dce)))
 779
 780
 781   (let* ((os (operating-system (inherit os)
 782                ;; Assume we have an initrd with the whole QEMU shebang.
 783
 784                ;; Force our own root file system.  Refer to it by UUID so that
 785                ;; it works regardless of how the image is used ("qemu -hda",
 786                ;; Xen, etc.).
 787                (file-systems (cons (file-system
 788                                      (mount-point "/")
 789                                      (device root-uuid)
 790                                      (type file-system-type))
 791                                    file-systems-to-keep))))
 792          (bootcfg (operating-system-bootcfg os)))
 793     (qemu-image  #:os os
 794                  #:bootcfg-drv bootcfg
 795                  #:bootloader (bootloader-configuration-bootloader
 796                                (operating-system-bootloader os))
 797                  #:disk-image-size disk-image-size
 798                  #:file-system-type file-system-type
 799                  #:file-system-uuid root-uuid
 800                  #:inputs `(("system" ,os)
 801                             ("bootcfg" ,bootcfg))
 802                  #:copy-inputs? #t)))
 803
 804 \f
 805 ;;;
 806 ;;; VMs that share file systems with the host.
 807 ;;;
 808
 809 (define (file-system->mount-tag fs)
 810   "Return a 9p mount tag for host file system FS."
 811   ;; QEMU mount tags must be ASCII, at most 31-byte long, cannot contain
 812   ;; slashes, and cannot start with '_'.  Compute an identifier that
 813   ;; corresponds to the rules.
 814   (string-append "TAG"
 815                  (string-drop (bytevector->base32-string
 816                                (sha1 (string->utf8 fs)))
 817                               4)))
 818
 819 (define (mapping->file-system mapping)
 820   "Return a 9p file system that realizes MAPPING."
 821   (match mapping
 822     (($ <file-system-mapping> source target writable?)
 823      (file-system
 824        (mount-point target)
 825        (device (file-system->mount-tag source))
 826        (type "9p")
 827        (flags (if writable? '() '(read-only)))
 828        (options "trans=virtio,cache=loose")
 829        (check? #f)
 830        (create-mount-point? #t)))))
 831
 832 (define* (virtualized-operating-system os mappings #:optional (full-boot? #f))
 833   "Return an operating system based on OS suitable for use in a virtualized
 834 environment with the store shared with the host.  MAPPINGS is a list of
 835 <file-system-mapping> to realize in the virtualized OS."
 836   (define user-file-systems
 837     ;; Remove file systems that conflict with those added below, or that are
 838     ;; normally bound to real devices.
 839     (remove (lambda (fs)
 840               (let ((target (file-system-mount-point fs))
 841                     (source (file-system-device fs)))
 842                 (or (string=? target (%store-prefix))
 843                     (string=? target "/")
 844                     (and (string? source)
 845                          (string-prefix? "/dev/" source))
 846
 847                     ;; Labels and UUIDs are necessarily invalid in the VM.
 848                     (and (file-system-mount? fs)
 849                          (or (file-system-label? source)
 850                              (uuid? source))))))
 851             (operating-system-file-systems os)))
 852
 853   (define virtual-file-systems
 854     (cons (file-system
 855             (mount-point "/")
 856             (device "/dev/vda1")
 857             (type "ext4"))
 858
 859           (append (map mapping->file-system mappings)
 860                   user-file-systems)))
 861
 862   (operating-system (inherit os)
 863
 864     ;; XXX: Until we run QEMU with UEFI support (with the OVMF firmware),
 865     ;; force the traditional i386/BIOS method.
 866     ;; See <https://bugs.gnu.org/28768>.
 867     (bootloader (bootloader-configuration
 868                   (inherit (operating-system-bootloader os))
 869                   (bootloader grub-bootloader)
 870                   (target "/dev/vda")))
 871
 872     (initrd (lambda (file-systems . rest)
 873               (apply (operating-system-initrd os)
 874                      file-systems
 875                      #:volatile-root? #t
 876                      rest)))
 877
 878     ;; Disable swap.
 879     (swap-devices '())
 880
 881     ;; XXX: When FULL-BOOT? is true, do not add a 9p mount for /gnu/store
 882     ;; since that would lead the bootloader config to look for the kernel and
 883     ;; initrd in it.
 884     (file-systems (if full-boot?
 885                       virtual-file-systems
 886                       (cons
 887                        (file-system
 888                          (inherit (mapping->file-system %store-mapping))
 889                          (needed-for-boot? #t))
 890                        virtual-file-systems)))))
 891
 892 (define* (system-qemu-image/shared-store
 893           os
 894           #:key
 895           full-boot?
 896           (disk-image-size (* (if full-boot? 500 30) (expt 2 20))))
 897   "Return a derivation that builds a QEMU image of OS that shares its store
 898 with the host.
 899
 900 When FULL-BOOT? is true, return an image that does a complete boot sequence,
 901 bootloaded included; thus, make a disk image that contains everything the
 902 bootloader refers to: OS kernel, initrd, bootloader data, etc."
 903   (define root-uuid
 904     ;; Use a fixed UUID to improve determinism.
 905     (operating-system-uuid os 'dce))
 906
 907   (define bootcfg
 908     (operating-system-bootcfg os))
 909
 910   ;; XXX: When FULL-BOOT? is true, we end up creating an image that contains
 911   ;; BOOTCFG and all its dependencies, including the output of OS.
 912   ;; This is more than needed (we only need the kernel, initrd, GRUB for its
 913   ;; font, and the background image), but it's hard to filter that.
 914   (qemu-image #:os os
 915               #:bootcfg-drv bootcfg
 916               #:bootloader (bootloader-configuration-bootloader
 917                             (operating-system-bootloader os))
 918               #:disk-image-size disk-image-size
 919               #:file-system-uuid root-uuid
 920               #:inputs (if full-boot?
 921                            `(("bootcfg" ,bootcfg))
 922                            '())
 923
 924               ;; XXX: Passing #t here is too slow, so let it off by default.
 925               #:register-closures? #f
 926               #:copy-inputs? full-boot?))
 927
 928 (define* (common-qemu-options image shared-fs)
 929   "Return the a string-value gexp with the common QEMU options to boot IMAGE,
 930 with '-virtfs' options for the host file systems listed in SHARED-FS."
 931
 932   (define (virtfs-option fs)
 933     #~(format #f "-virtfs local,path=~s,security_model=none,mount_tag=~s"
 934               #$fs #$(file-system->mount-tag fs)))
 935
 936   #~(;; Only enable kvm if we see /dev/kvm exists.
 937      ;; This allows users without hardware virtualization to still use these
 938      ;; commands.
 939      #$@(if (file-exists? "/dev/kvm")
 940             '("-enable-kvm")
 941             '())
 942
 943      "-no-reboot"
 944      "-nic" "user,model=virtio-net-pci"
 945      "-object" "rng-random,filename=/dev/urandom,id=guixsd-vm-rng"
 946      "-device" "virtio-rng-pci,rng=guixsd-vm-rng"
 947
 948      #$@(map virtfs-option shared-fs)
 949      "-vga std"
 950      (format #f "-drive file=~a,if=virtio,cache=writeback,werror=report,readonly"
 951              #$image)))
 952
 953 (define* (system-qemu-image/shared-store-script os
 954                                                 #:key
 955                                                 (qemu qemu)
 956                                                 (graphic? #t)
 957                                                 (memory-size 256)
 958                                                 (mappings '())
 959                                                 full-boot?
 960                                                 (disk-image-size
 961                                                  (* (if full-boot? 500 70)
 962                                                     (expt 2 20)))
 963                                                 (options '()))
 964   "Return a derivation that builds a script to run a virtual machine image of
 965 OS that shares its store with the host.  The virtual machine runs with
 966 MEMORY-SIZE MiB of memory.
 967
 968 MAPPINGS is a list of <file-system-mapping> specifying mapping of host file
 969 systems into the guest.
 970
 971 When FULL-BOOT? is true, the returned script runs everything starting from the
 972 bootloader; otherwise it directly starts the operating system kernel.  The
 973 DISK-IMAGE-SIZE parameter specifies the size in bytes of the root disk image;
 974 it is mostly useful when FULL-BOOT?  is true."
 975   (mlet* %store-monad ((os ->  (virtualized-operating-system os mappings full-boot?))
 976                        (image  (system-qemu-image/shared-store
 977                                 os
 978                                 #:full-boot? full-boot?
 979                                 #:disk-image-size disk-image-size)))
 980     (define kernel-arguments
 981       #~(list #$@(if graphic? #~() #~("console=ttyS0"))
 982               #+@(operating-system-kernel-arguments os "/dev/vda1")))
 983
 984     (define qemu-exec
 985       #~(list (string-append #$qemu "/bin/" #$(qemu-command (%current-system)))
 986               #$@(if full-boot?
 987                      #~()
 988                      #~("-kernel" #$(operating-system-kernel-file os)
 989                         "-initrd" #$(file-append os "/initrd")
 990                         (format #f "-append ~s"
 991                                 (string-join #$kernel-arguments " "))))
 992               #$@(common-qemu-options image
 993                                       (map file-system-mapping-source
 994                                            (cons %store-mapping mappings)))
 995               "-m " (number->string #$memory-size)
 996               #$@options))
 997
 998     (define builder
 999       #~(call-with-output-file #$output
1000           (lambda (port)
1001             (format port "#!~a~% exec ~a \"$@\"~%"
1002                     #$(file-append bash "/bin/sh")
1003                     (string-join #$qemu-exec " "))
1004             (chmod port #o555))))
1005
1006     (gexp->derivation "run-vm.sh" builder)))
1007
1008 \f
1009 ;;;
1010 ;;; High-level abstraction.
1011 ;;;
1012
1013 (define-record-type* <virtual-machine> %virtual-machine
1014   make-virtual-machine
1015   virtual-machine?
1016   (operating-system virtual-machine-operating-system) ;<operating-system>
1017   (qemu             virtual-machine-qemu              ;<package>
1018                     (default qemu))
1019   (graphic?         virtual-machine-graphic?      ;Boolean
1020                     (default #f))
1021   (memory-size      virtual-machine-memory-size   ;integer (MiB)
1022                     (default 256))
1023   (disk-image-size  virtual-machine-disk-image-size   ;integer (bytes)
1024                     (default 'guess))
1025   (port-forwardings virtual-machine-port-forwardings ;list of integer pairs
1026                     (default '())))
1027
1028 (define-syntax virtual-machine
1029   (syntax-rules ()
1030     "Declare a virtual machine running the specified OS, with the given
1031 options."
1032     ((_ os)                                       ;shortcut
1033      (%virtual-machine (operating-system os)))
1034     ((_ fields ...)
1035      (%virtual-machine fields ...))))
1036
1037 (define (port-forwardings->qemu-options forwardings)
1038   "Return the QEMU option for the given port FORWARDINGS as a string, where
1039 FORWARDINGS is a list of host-port/guest-port pairs."
1040   (string-join
1041    (map (match-lambda
1042           ((host-port . guest-port)
1043            (string-append "hostfwd=tcp::"
1044                           (number->string host-port)
1045                           "-:" (number->string guest-port))))
1046         forwardings)
1047    ","))
1048
1049 (define-gexp-compiler (virtual-machine-compiler (vm <virtual-machine>)
1050                                                 system target)
1051   ;; XXX: SYSTEM and TARGET are ignored.
1052   (match vm
1053     (($ <virtual-machine> os qemu graphic? memory-size disk-image-size ())
1054      (system-qemu-image/shared-store-script os
1055                                             #:qemu qemu
1056                                             #:graphic? graphic?
1057                                             #:memory-size memory-size
1058                                             #:disk-image-size
1059                                             disk-image-size))
1060     (($ <virtual-machine> os qemu graphic? memory-size disk-image-size
1061                           forwardings)
1062      (let ((options
1063             `("-nic" ,(string-append
1064                        "user,model=virtio-net-pci,"
1065                        (port-forwardings->qemu-options forwardings)))))
1066        (system-qemu-image/shared-store-script os
1067                                               #:qemu qemu
1068                                               #:graphic? graphic?
1069                                               #:memory-size memory-size
1070                                               #:disk-image-size
1071                                               disk-image-size
1072                                               #:options options)))))
1073
1074 ;;; vm.scm ends here