;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2016 Christopher Allan Webber <cwebber@dustycloud.org>
;;; Copyright © 2016 Leo Famulari <leo@famulari.name>
;;;
;;; 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 system vm)
#:use-module (guix config)
#:use-module (guix store)
#:use-module (guix gexp)
#:use-module (guix derivations)
#:use-module (guix packages)
#:use-module (guix monads)
#:use-module (guix records)
#:use-module (guix modules)
#:use-module ((gnu build vm)
#:select (qemu-command))
#:use-module (gnu packages base)
#:use-module (gnu packages bootloaders)
#:use-module (gnu packages guile)
#:use-module (gnu packages gawk)
#:use-module (gnu packages bash)
#:use-module (gnu packages less)
#:use-module (gnu packages qemu)
#:use-module (gnu packages disk)
#:use-module (gnu packages zile)
#:use-module (gnu packages linux)
#:use-module (gnu packages package-management)
#:use-module ((gnu packages make-bootstrap)
#:select (%guile-static-stripped))
#:use-module (gnu packages admin)
#:use-module (gnu system shadow)
#:use-module (gnu system pam)
#:use-module (gnu system linux-initrd)
#:use-module (gnu system grub)
#:use-module (gnu system file-systems)
#:use-module (gnu system)
#:use-module (gnu services)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-26)
#:use-module (ice-9 match)
#:export (expression->derivation-in-linux-vm
qemu-image
virtualized-operating-system
system-qemu-image
system-qemu-image/shared-store
system-qemu-image/shared-store-script
system-disk-image))
;;; Commentary:
;;;
;;; Tools to evaluate build expressions within virtual machines.
;;;
;;; Code:
(define %linux-vm-file-systems
;; File systems mounted for 'derivation-in-linux-vm'. The store and /xchg
;; directory are shared with the host over 9p.
(list (file-system
(mount-point (%store-prefix))
(device "store")
(type "9p")
(needed-for-boot? #t)
(options "trans=virtio")
(check? #f))
(file-system
(mount-point "/xchg")
(device "xchg")
(type "9p")
(needed-for-boot? #t)
(options "trans=virtio")
(check? #f))))
(define* (expression->derivation-in-linux-vm name exp
#:key
(system (%current-system))
(linux linux-libre)
initrd
(qemu qemu-minimal)
(env-vars '())
(guile-for-build
(%guile-for-build))
(make-disk-image? #f)
(references-graphs #f)
(memory-size 256)
(disk-image-format "qcow2")
(disk-image-size
(* 100 (expt 2 20))))
"Evaluate EXP in a QEMU virtual machine running LINUX with INITRD (a
derivation). In the virtual machine, EXP has access to all its inputs from the
store; it should put its output files in the `/xchg' directory, which is
copied to the derivation's output when the VM terminates. The virtual machine
runs with MEMORY-SIZE MiB of memory.
When MAKE-DISK-IMAGE? is true, then create a QEMU disk image of type
DISK-IMAGE-FORMAT (e.g., 'qcow2' or 'raw'), of DISK-IMAGE-SIZE bytes and
return it.
When REFERENCES-GRAPHS is true, it must be a list of file name/store path
pairs, as for `derivation'. The files containing the reference graphs are
made available under the /xchg CIFS share."
(mlet* %store-monad
((user-builder (gexp->file "builder-in-linux-vm" exp))
(loader (gexp->file "linux-vm-loader"
#~(primitive-load #$user-builder)))
(coreutils -> (canonical-package coreutils))
(initrd (if initrd ; use the default initrd?
(return initrd)
(base-initrd %linux-vm-file-systems
#:linux linux
#:virtio? #t
#:qemu-networking? #t))))
(define builder
;; Code that launches the VM that evaluates EXP.
(with-imported-modules (source-module-closure '((guix build utils)
(gnu build vm)))
#~(begin
(use-modules (guix build utils)
(gnu build vm))
(let ((inputs '#$(list qemu coreutils))
(linux (string-append #$linux "/"
#$(system-linux-image-file-name)))
(initrd (string-append #$initrd "/initrd"))
(loader #$loader)
(graphs '#$(match references-graphs
(((graph-files . _) ...) graph-files)
(_ #f))))
(set-path-environment-variable "PATH" '("bin") inputs)
(load-in-linux-vm loader
#:output #$output
#:linux linux #:initrd initrd
#:memory-size #$memory-size
#:make-disk-image? #$make-disk-image?
#:disk-image-format #$disk-image-format
#:disk-image-size #$disk-image-size
#:references-graphs graphs)))))
(gexp->derivation name builder
;; TODO: Require the "kvm" feature.
#:system system
#:env-vars env-vars
#:guile-for-build guile-for-build
#:references-graphs references-graphs)))
(define* (qemu-image #:key
(name "qemu-image")
(system (%current-system))
(qemu qemu-minimal)
(disk-image-size (* 100 (expt 2 20)))
(disk-image-format "qcow2")
(file-system-type "ext4")
file-system-label
os-derivation
grub-configuration
(register-closures? #t)
(inputs '())
copy-inputs?)
"Return a bootable, stand-alone QEMU image of type DISK-IMAGE-FORMAT (e.g.,
'qcow2' or 'raw'), with a root partition of type FILE-SYSTEM-TYPE.
Optionally, FILE-SYSTEM-LABEL can be specified as the volume name for the root
partition. The returned image is a full disk image that runs OS-DERIVATION,
with a GRUB installation that uses GRUB-CONFIGURATION as its configuration
file (GRUB-CONFIGURATION must be the name of a file in the VM.)
INPUTS is a list of inputs (as for packages). When COPY-INPUTS? is true, copy
all of INPUTS into the image being built. When REGISTER-CLOSURES? is true,
register INPUTS in the store database of the image so that Guix can be used in
the image."
(expression->derivation-in-linux-vm
name
(with-imported-modules (source-module-closure '((gnu build vm)
(guix build utils)))
#~(begin
(use-modules (gnu build vm)
(guix build utils))
(let ((inputs
'#$(append (list qemu parted grub e2fsprogs)
(map canonical-package
(list sed grep coreutils findutils gawk))
(if register-closures? (list guix) '())))
;; This variable is unused but allows us to add INPUTS-TO-COPY
;; as inputs.
(to-register
'#$(map (match-lambda
((name thing) thing)
((name thing output) `(,thing ,output)))
inputs)))
(set-path-environment-variable "PATH" '("bin" "sbin") inputs)
(let* ((graphs '#$(match inputs
(((names . _) ...)
names)))
(initialize (root-partition-initializer
#:closures graphs
#:copy-closures? #$copy-inputs?
#:register-closures? #$register-closures?
#:system-directory #$os-derivation))
(partitions (list (partition
(size #$(- disk-image-size
(* 10 (expt 2 20))))
(label #$file-system-label)
(file-system #$file-system-type)
(bootable? #t)
(initializer initialize)))))
(initialize-hard-disk "/dev/vda"
#:partitions partitions
#:grub.cfg #$grub-configuration)
(reboot)))))
#:system system
#:make-disk-image? #t
#:disk-image-size disk-image-size
#:disk-image-format disk-image-format
#:references-graphs inputs))
;;;
;;; VM and disk images.
;;;
(define* (system-disk-image os
#:key
(name "disk-image")
(file-system-type "ext4")
(disk-image-size (* 900 (expt 2 20)))
(volatile? #t))
"Return the derivation of a disk image of DISK-IMAGE-SIZE bytes of the
system described by OS. Said image can be copied on a USB stick as is. When
VOLATILE? is true, the root file system is made volatile; this is useful
to USB sticks meant to be read-only."
(define root-label
;; Volume name of the root file system. Since we don't know which device
;; will hold it, we use the volume name to find it (using the UUID would
;; be even better, but somewhat less convenient.)
"gnu-disk-image")
(define file-systems-to-keep
(remove (lambda (fs)
(string=? (file-system-mount-point fs) "/"))
(operating-system-file-systems os)))
(let ((os (operating-system (inherit os)
;; Since this is meant to be used on real hardware, don't
;; install QEMU networking or anything like that. Assume USB
;; mass storage devices (usb-storage.ko) are available.
(initrd (lambda (file-systems . rest)
(apply base-initrd file-systems
#:volatile-root? #t
rest)))
;; Force our own root file system.
(file-systems (cons (file-system
(mount-point "/")
(device root-label)
(title 'label)
(type file-system-type))
file-systems-to-keep)))))
(mlet* %store-monad ((os-drv (operating-system-derivation os))
(grub.cfg (operating-system-grub.cfg os)))
(qemu-image #:name name
#:os-derivation os-drv
#:grub-configuration grub.cfg
#:disk-image-size disk-image-size
#:disk-image-format "raw"
#:file-system-type file-system-type
#:file-system-label root-label
#:copy-inputs? #t
#:register-closures? #t
#:inputs `(("system" ,os-drv)
("grub.cfg" ,grub.cfg))))))
(define* (system-qemu-image os
#:key
(file-system-type "ext4")
(disk-image-size (* 900 (expt 2 20))))
"Return the derivation of a freestanding QEMU image of DISK-IMAGE-SIZE bytes
of the GNU system as described by OS."
(define file-systems-to-keep
;; Keep only file systems other than root and not normally bound to real
;; devices.
(remove (lambda (fs)
(let ((target (file-system-mount-point fs))
(source (file-system-device fs)))
(or (string=? target "/")
(string-prefix? "/dev/" source))))
(operating-system-file-systems os)))
(let ((os (operating-system (inherit os)
;; Use an initrd with the whole QEMU shebang.
(initrd (lambda (file-systems . rest)
(apply base-initrd file-systems
#:virtio? #t
rest)))
;; Force our own root file system.
(file-systems (cons (file-system
(mount-point "/")
(device "/dev/sda1")
(type file-system-type))
file-systems-to-keep)))))
(mlet* %store-monad
((os-drv (operating-system-derivation os))
(grub.cfg (operating-system-grub.cfg os)))
(qemu-image #:os-derivation os-drv
#:grub-configuration grub.cfg
#:disk-image-size disk-image-size
#:file-system-type file-system-type
#:inputs `(("system" ,os-drv)
("grub.cfg" ,grub.cfg))
#:copy-inputs? #t))))
;;;
;;; VMs that share file systems with the host.
;;;
(define (file-system->mount-tag fs)
"Return a 9p mount tag for host file system FS."
;; QEMU mount tags cannot contain slashes and cannot start with '_'.
;; Compute an identifier that corresponds to the rules.
(string-append "TAG"
(string-map (match-lambda
(#\/ #\_)
(chr chr))
fs)))
(define (mapping->file-system mapping)
"Return a 9p file system that realizes MAPPING."
(match mapping
(($ <file-system-mapping> source target writable?)
(file-system
(mount-point target)
(device (file-system->mount-tag source))
(type "9p")
(flags (if writable? '() '(read-only)))
(options (string-append "trans=virtio"))
(check? #f)
(create-mount-point? #t)))))
(define* (virtualized-operating-system os mappings #:optional (full-boot? #f))
"Return an operating system based on OS suitable for use in a virtualized
environment with the store shared with the host. MAPPINGS is a list of
<file-system-mapping> to realize in the virtualized OS."
(define user-file-systems
;; Remove file systems that conflict with those added below, or that are
;; normally bound to real devices.
(remove (lambda (fs)
(let ((target (file-system-mount-point fs))
(source (file-system-device fs)))
(or (string=? target (%store-prefix))
(string=? target "/")
(and (eq? 'device (file-system-title fs))
(string-prefix? "/dev/" source)))))
(operating-system-file-systems os)))
(define virtual-file-systems
(cons (file-system
(mount-point "/")
(device "/dev/vda1")
(type "ext4"))
(append (map mapping->file-system mappings)
user-file-systems)))
(operating-system (inherit os)
(initrd (lambda (file-systems . rest)
(apply base-initrd file-systems
#:volatile-root? #t
#:virtio? #t
rest)))
;; Disable swap.
(swap-devices '())
;; XXX: When FULL-BOOT? is true, do not add a 9p mount for /gnu/store
;; since that would lead the bootloader config to look for the kernel and
;; initrd in it.
(file-systems (if full-boot?
virtual-file-systems
(cons
(file-system
(inherit (mapping->file-system %store-mapping))
(needed-for-boot? #t))
virtual-file-systems)))))
(define* (system-qemu-image/shared-store
os
#:key
full-boot?
(disk-image-size (* (if full-boot? 500 30) (expt 2 20))))
"Return a derivation that builds a QEMU image of OS that shares its store
with the host.
When FULL-BOOT? is true, return an image that does a complete boot sequence,
bootloaded included; thus, make a disk image that contains everything the
bootloader refers to: OS kernel, initrd, bootloader data, etc."
(mlet* %store-monad ((os-drv (operating-system-derivation os))
(grub.cfg (operating-system-grub.cfg os)))
;; XXX: When FULL-BOOT? is true, we end up creating an image that contains
;; GRUB.CFG and all its dependencies, including the output of OS-DRV.
;; This is more than needed (we only need the kernel, initrd, GRUB for its
;; font, and the background image), but it's hard to filter that.
(qemu-image #:os-derivation os-drv
#:grub-configuration grub.cfg
#:disk-image-size disk-image-size
#:inputs (if full-boot?
`(("grub.cfg" ,grub.cfg))
'())
;; XXX: Passing #t here is too slow, so let it off by default.
#:register-closures? #f
#:copy-inputs? full-boot?)))
(define* (common-qemu-options image shared-fs)
"Return the a string-value gexp with the common QEMU options to boot IMAGE,
with '-virtfs' options for the host file systems listed in SHARED-FS."
(define (virtfs-option fs)
#~(format #f "-virtfs local,path=~s,security_model=none,mount_tag=~s"
#$fs #$(file-system->mount-tag fs)))
#~(;; Only enable kvm if we see /dev/kvm exists.
;; This allows users without hardware virtualization to still use these
;; commands.
#$@(if (file-exists? "/dev/kvm")
'("-enable-kvm")
'())
"-no-reboot"
"-net nic,model=virtio"
#$@(map virtfs-option shared-fs)
"-vga std"
(format #f "-drive file=~a,if=virtio,cache=writeback,werror=report,readonly"
#$image)
"-m 256"))
(define* (system-qemu-image/shared-store-script os
#:key
(qemu qemu)
(graphic? #t)
(mappings '())
full-boot?
(disk-image-size
(* (if full-boot? 500 30)
(expt 2 20))))
"Return a derivation that builds a script to run a virtual machine image of
OS that shares its store with the host.
MAPPINGS is a list of <file-system-mapping> specifying mapping of host file
systems into the guest.
When FULL-BOOT? is true, the returned script runs everything starting from the
bootloader; otherwise it directly starts the operating system kernel. The
DISK-IMAGE-SIZE parameter specifies the size in bytes of the root disk image;
it is mostly useful when FULL-BOOT? is true."
(mlet* %store-monad ((os -> (virtualized-operating-system os mappings full-boot?))
(os-drv (operating-system-derivation os))
(image (system-qemu-image/shared-store
os
#:full-boot? full-boot?
#:disk-image-size disk-image-size)))
(define kernel-arguments
#~(list "--root=/dev/vda1"
(string-append "--system=" #$os-drv)
(string-append "--load=" #$os-drv "/boot")
#$@(if graphic? #~() #~("console=ttyS0"))
#+@(operating-system-kernel-arguments os)))
(define qemu-exec
#~(list (string-append #$qemu "/bin/" #$(qemu-command (%current-system)))
#$@(if full-boot?
#~()
#~("-kernel" #$(operating-system-kernel-file os)
"-initrd" #$(file-append os-drv "/initrd")
(format #f "-append ~s"
(string-join #$kernel-arguments " "))))
#$@(common-qemu-options image
(map file-system-mapping-source
(cons %store-mapping mappings)))))
(define builder
#~(call-with-output-file #$output
(lambda (port)
(format port "#!~a~% exec ~a \"$@\"~%"
#$(file-append bash "/bin/sh")
(string-join #$qemu-exec " "))
(chmod port #o555))))
(gexp->derivation "run-vm.sh" builder)))
;;; vm.scm ends here