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Diffstat (limited to 'gnu/system/linux-initrd.scm')
-rw-r--r-- | gnu/system/linux-initrd.scm | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/gnu/system/linux-initrd.scm b/gnu/system/linux-initrd.scm new file mode 100644 index 0000000000..9520473d01 --- /dev/null +++ b/gnu/system/linux-initrd.scm @@ -0,0 +1,248 @@ +;;; 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 system linux-initrd) + #:use-module (guix monads) + #:use-module (guix utils) + #:use-module ((guix store) + #:select (%store-prefix)) + #: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 (ice-9 regex) + #:export (expression->initrd + qemu-initrd + gnu-system-initrd)) + + +;;; Commentary: +;;; +;;; Tools to build initial RAM disks (initrd's) for Linux-Libre, and in +;;; particular initrd's that run Guile. +;;; +;;; Code: + + +(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 (string->regexp str) + ;; Return a regexp that matches STR exactly. + (string-append "^" (regexp-quote str) "$")) + + (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 + ,(string->regexp 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"))))))))) + + (mlet* %store-monad + ((source (imported-modules modules)) + (compiled (compiled-modules modules)) + (inputs (lower-inputs + `(("guile" ,guile) + ("cpio" ,cpio) + ("gzip" ,gzip) + ("modules" ,source) + ("modules/compiled" ,compiled) + ,@(if linux + `(("linux" ,linux)) + '()))))) + (derivation-expression name builder + #:modules '((guix build utils)) + #:inputs inputs))) + +(define* (qemu-initrd #:key + guile-modules-in-chroot? + volatile-root? + (mounts `((cifs "/store" ,(%store-prefix)) + (cifs "/xchg" "/xchg")))) + "Return a monadic derivation that builds an initrd for use in a QEMU guest +where the store is shared with the host. MOUNTS is a list of file systems to +be mounted atop the root file system, where each item has the form: + + (FILE-SYSTEM-TYPE SOURCE TARGET) + +When GUILE-MODULES-IN-CHROOT? is true, make core Guile modules available in +the new root. This is necessary is the file specified as '--load' needs +access to these modules (which is the case if it wants to even just print an +exception and backtrace!). + +When VOLATILE-ROOT? is true, the root file system is writable but any changes +to it are lost." + (define cifs-modules + ;; Modules needed to mount CIFS file systems. + '("md4.ko" "ecb.ko" "cifs.ko")) + + (define virtio-9p-modules + ;; Modules for the 9p paravirtualized file system. + '("9pnet.ko" "9p.ko" "9pnet_virtio.ko")) + + (define linux-modules + ;; Modules added to the initrd and loaded from the initrd. + `("virtio.ko" "virtio_ring.ko" "virtio_pci.ko" + "virtio_balloon.ko" "virtio_blk.ko" "virtio_net.ko" + ,@(if (assoc-ref mounts 'cifs) + cifs-modules + '()) + ,@(if (assoc-ref mounts '9p) + virtio-9p-modules + '()))) + + (expression->initrd + `(begin + (use-modules (guix build linux-initrd)) + + (boot-system #:mounts ',mounts + #:linux-modules ',linux-modules + #:qemu-guest-networking? #t + #:guile-modules-in-chroot? ',guile-modules-in-chroot? + #:volatile-root? ',volatile-root?)) + #:name "qemu-initrd" + #:modules '((guix build utils) + (guix build linux-initrd)) + #:linux linux-libre + #:linux-modules linux-modules)) + +(define (gnu-system-initrd) + "Initrd for the GNU system itself, with nothing QEMU-specific." + (qemu-initrd #:guile-modules-in-chroot? #f)) + +;;; linux-initrd.scm ends here |