guix/gnu/packages/linux-initrd.scm
Ludovic Courtès fbd1c3e95b gnu: linux-initrd: Mount /tmp as a tmpfs.
* gnu/packages/linux-initrd.scm (gnu-system-initrd): Make sure /root/tmp
  exists; mount it as a tmpfs.
2013-09-27 00:46:17 +02:00

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;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013 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 packages linux-initrd)
#:use-module (guix utils)
#:use-module (guix licenses)
#:use-module (guix build-system)
#:use-module ((guix derivations)
#:select (imported-modules compiled-modules %guile-for-build))
#:use-module (gnu packages)
#:use-module (gnu packages cpio)
#:use-module (gnu packages compression)
#:use-module (gnu packages linux)
#:use-module (gnu packages guile)
#:use-module ((gnu packages make-bootstrap)
#:select (%guile-static-stripped))
#:use-module (guix packages)
#:use-module (guix download)
#:use-module (guix build-system trivial))
;;; Commentary:
;;;
;;; Tools to build initial RAM disks (initrd's) for Linux-Libre, and in
;;; particular initrd's that run Guile.
;;;
;;; Code:
(define-syntax-rule (raw-build-system (store system name inputs) body ...)
"Lift BODY to a package build system."
;; TODO: Generalize.
(build-system
(name "raw")
(description "Raw build system")
(build (lambda* (store name source inputs #:key system #:allow-other-keys)
(parameterize ((%guile-for-build (package-derivation store
guile-2.0)))
body ...)))))
(define (module-package modules)
"Return a package that contains all of MODULES, a list of Guile module
names."
(package
(name "guile-modules")
(version "0")
(source #f)
(build-system (raw-build-system (store system name inputs)
(imported-modules store modules
#:name name
#:system system)))
(synopsis "Set of Guile modules")
(description synopsis)
(license gpl3+)
(home-page "http://www.gnu.org/software/guix/")))
(define (compiled-module-package modules)
"Return a package that contains the .go files corresponding to MODULES, a
list of Guile module names."
(package
(name "guile-compiled-modules")
(version "0")
(source #f)
(build-system (raw-build-system (store system name inputs)
(compiled-modules store modules
#:name name
#:system system)))
(synopsis "Set of compiled Guile modules")
(description synopsis)
(license gpl3+)
(home-page "http://www.gnu.org/software/guix/")))
(define* (expression->initrd exp
#:key
(guile %guile-static-stripped)
(cpio cpio)
(gzip gzip)
(name "guile-initrd")
(system (%current-system))
(modules '())
(linux #f)
(linux-modules '()))
"Return a package that contains a Linux initrd (a gzipped cpio archive)
containing GUILE and that evaluates EXP upon booting. LINUX-MODULES is a list
of `.ko' file names to be copied from LINUX into the initrd. MODULES is a
list of Guile module names to be embedded in the initrd."
;; General Linux overview in `Documentation/early-userspace/README' and
;; `Documentation/filesystems/ramfs-rootfs-initramfs.txt'.
(define builder
`(begin
(use-modules (guix build utils)
(ice-9 pretty-print)
(ice-9 popen)
(ice-9 match)
(ice-9 ftw)
(srfi srfi-26)
(system base compile)
(rnrs bytevectors)
((system foreign) #:select (sizeof)))
(let ((guile (assoc-ref %build-inputs "guile"))
(cpio (string-append (assoc-ref %build-inputs "cpio")
"/bin/cpio"))
(gzip (string-append (assoc-ref %build-inputs "gzip")
"/bin/gzip"))
(modules (assoc-ref %build-inputs "modules"))
(gos (assoc-ref %build-inputs "modules/compiled"))
(scm-dir (string-append "share/guile/" (effective-version)))
(go-dir (format #f ".cache/guile/ccache/~a-~a-~a-~a"
(effective-version)
(if (eq? (native-endianness) (endianness little))
"LE"
"BE")
(sizeof '*)
(effective-version)))
(out (assoc-ref %outputs "out")))
(mkdir out)
(mkdir "contents")
(with-directory-excursion "contents"
(copy-recursively guile ".")
(call-with-output-file "init"
(lambda (p)
(format p "#!/bin/guile -ds~%!#~%" guile)
(pretty-print ',exp p)))
(chmod "init" #o555)
(chmod "bin/guile" #o555)
;; Copy Guile modules.
(chmod scm-dir #o777)
(copy-recursively modules scm-dir
#:follow-symlinks? #t)
(copy-recursively gos (string-append "lib/guile/"
(effective-version) "/ccache")
#:follow-symlinks? #t)
;; Compile `init'.
(mkdir-p go-dir)
(set! %load-path (cons modules %load-path))
(set! %load-compiled-path (cons gos %load-compiled-path))
(compile-file "init"
#:opts %auto-compilation-options
#:output-file (string-append go-dir "/init.go"))
;; Copy Linux modules.
(let* ((linux (assoc-ref %build-inputs "linux"))
(module-dir (and linux
(string-append linux "/lib/modules"))))
(mkdir "modules")
,@(map (lambda (module)
`(match (find-files module-dir ,module)
((file)
(format #t "copying '~a'...~%" file)
(copy-file file (string-append "modules/"
,module)))
(()
(error "module not found" ,module module-dir))
((_ ...)
(error "several modules by that name"
,module module-dir))))
linux-modules))
;; Reset the timestamps of all the files that will make it in the
;; initrd.
(for-each (cut utime <> 0 0 0 0)
(find-files "." ".*"))
(system* cpio "--version")
(let ((pipe (open-pipe* OPEN_WRITE cpio "-o"
"-O" (string-append out "/initrd")
"-H" "newc" "--null")))
(define print0
(let ((len (string-length "./")))
(lambda (file)
(format pipe "~a\0" (string-drop file len)))))
;; Note: as per `ramfs-rootfs-initramfs.txt', always add
;; directory entries before the files that are inside of it: "The
;; Linux kernel cpio extractor won't create files in a directory
;; that doesn't exist, so the directory entries must go before
;; the files that go in those directories."
(file-system-fold (const #t)
(lambda (file stat result) ; leaf
(print0 file))
(lambda (dir stat result) ; down
(unless (string=? dir ".")
(print0 dir)))
(const #f) ; up
(const #f) ; skip
(const #f)
#f
".")
(and (zero? (close-pipe pipe))
(with-directory-excursion out
(and (zero? (system* gzip "--best" "initrd"))
(rename-file "initrd.gz" "initrd")))))))))
(let ((name* name))
(package
(name name*)
(version "0")
(source #f)
(build-system trivial-build-system)
(arguments `(#:modules ((guix build utils))
#:builder ,builder))
(inputs `(("guile" ,guile)
("cpio" ,cpio)
("gzip" ,gzip)
("modules" ,(module-package modules))
("modules/compiled" ,(compiled-module-package modules))
,@(if linux
`(("linux" ,linux))
'())))
(synopsis "An initial RAM disk (initrd) for the Linux kernel")
(description
"An initial RAM disk (initrd), really a gzipped cpio archive, for use by
the Linux kernel.")
(license gpl3+)
(home-page "http://www.gnu.org/software/guix/"))))
(define-public qemu-initrd
(expression->initrd
'(begin
(use-modules (srfi srfi-1)
(srfi srfi-26)
(ice-9 match)
((system base compile) #:select (compile-file))
(guix build utils)
(guix build linux-initrd))
(display "Welcome, this is GNU's early boot Guile.\n")
(display "Use '--repl' for an initrd REPL.\n\n")
(mount-essential-file-systems)
(let* ((args (linux-command-line))
(option (lambda (opt)
(let ((opt (string-append opt "=")))
(and=> (find (cut string-prefix? opt <>)
args)
(lambda (arg)
(substring arg (+ 1 (string-index arg #\=))))))))
(to-load (option "--load"))
(root (option "--root")))
(when (member "--repl" args)
((@ (system repl repl) start-repl)))
(display "loading CIFS and companion modules...\n")
(for-each (compose load-linux-module*
(cut string-append "/modules/" <>))
(list "md4.ko" "ecb.ko" "cifs.ko"))
(unless (configure-qemu-networking)
(display "network interface is DOWN\n"))
;; Make /dev nodes.
(make-essential-device-nodes)
;; Prepare the real root file system under /root.
(unless (file-exists? "/root")
(mkdir "/root"))
(if root
(mount root "/root" "ext3")
(mount "none" "/root" "tmpfs"))
(mount-essential-file-systems #:root "/root")
(mkdir "/root/xchg")
(mkdir-p "/root/nix/store")
(unless (file-exists? "/root/dev")
(mkdir "/root/dev")
(make-essential-device-nodes #:root "/root"))
;; Mount the host's store and exchange directory.
(mount-qemu-smb-share "/store" "/root/nix/store")
(mount-qemu-smb-share "/xchg" "/root/xchg")
;; Copy the directories that contain .scm and .go files so that the
;; child process in the chroot can load modules (we would bind-mount
;; them but for some reason that fails with EINVAL -- XXX).
(mkdir "/root/share")
(mkdir "/root/lib")
(mount "none" "/root/share" "tmpfs")
(mount "none" "/root/lib" "tmpfs")
(copy-recursively "/share" "/root/share"
#:log (%make-void-port "w"))
(copy-recursively "/lib" "/root/lib"
#:log (%make-void-port "w"))
(if to-load
(begin
(format #t "loading boot file '~a'...\n" to-load)
(compile-file (string-append "/root/" to-load)
#:output-file "/root/loader.go"
#:opts %auto-compilation-options)
(match (primitive-fork)
(0
(chroot "/root")
(load-compiled "/loader.go")
;; TODO: Remove /lib, /share, and /loader.go.
)
(pid
(format #t "boot file loaded under PID ~a~%" pid)
(let ((status (waitpid pid)))
(reboot)))))
(begin
(display "no boot file passed via '--load'\n")
(display "entering a warm and cozy REPL\n")
((@ (system repl repl) start-repl))))))
#:name "qemu-initrd"
#:modules '((guix build utils)
(guix build linux-initrd))
#:linux linux-libre
#:linux-modules '("cifs.ko" "md4.ko" "ecb.ko")))
(define-public gnu-system-initrd
;; Initrd for the GNU system itself, with nothing QEMU-specific.
(expression->initrd
'(begin
(use-modules (srfi srfi-1)
(srfi srfi-26)
(ice-9 match)
(guix build utils)
(guix build linux-initrd))
(display "Welcome, this is GNU's early boot Guile.\n")
(display "Use '--repl' for an initrd REPL.\n\n")
(mount-essential-file-systems)
(let* ((args (linux-command-line))
(option (lambda (opt)
(let ((opt (string-append opt "=")))
(and=> (find (cut string-prefix? opt <>)
args)
(lambda (arg)
(substring arg (+ 1 (string-index arg #\=))))))))
(to-load (option "--load"))
(root (option "--root")))
(when (member "--repl" args)
((@ (system repl repl) start-repl)))
;; Make /dev nodes.
(make-essential-device-nodes)
;; Prepare the real root file system under /root.
(mkdir-p "/root")
(if root
;; Assume ROOT has a usable /dev tree.
(mount root "/root" "ext3")
(begin
(mount "none" "/root" "tmpfs")
(make-essential-device-nodes #:root "/root")))
(mount-essential-file-systems #:root "/root")
(mkdir-p "/root/tmp")
(mount "none" "/root/tmp" "tmpfs")
;; XXX: We don't copy our fellow Guile modules to /root (see
;; 'qemu-initrd'), so if TO-LOAD tries to load a module (which can
;; happen if it throws, to display the exception!), then we're
;; screwed. Hopefully TO-LOAD is a simple expression that just does
;; '(execlp ...)'.
(if to-load
(begin
(format #t "loading '~a'...\n" to-load)
(chroot "/root")
(primitive-load to-load)
(format (current-error-port)
"boot program '~a' terminated, rebooting~%"
to-load)
(sleep 2)
(reboot))
(begin
(display "no init file passed via '--exec'\n")
(display "entering a warm and cozy REPL\n")
((@ (system repl repl) start-repl))))))
#:name "qemu-system-initrd"
#:modules '((guix build linux-initrd)
(guix build utils))
#:linux linux-libre))
;;; linux-initrd.scm ends here