From 0276f697b3dbab417dcad7ff32dfb4b9fb330ec4 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Fri, 21 Nov 2014 00:02:26 +0100 Subject: guix system: Add '--share' and '--expose' options for 'vm'. * guix/scripts/system.scm (system-derivation-for-action): Add #:mappings parameter. Pass it to 'system-qemu-image/shared-store-script'. (perform-action): Likewise. (show-help): Document --share and --expose. (specification->file-system-mapping): New procedure. (%options): Add --share and --expose. (guix-system): Pass #:mapping to 'perform-action'. * doc/guix.texi (Invoking guix system): Document it. --- doc/guix.texi | 15 +++++++++++++++ guix/scripts/system.scm | 45 +++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 56 insertions(+), 4 deletions(-) diff --git a/doc/guix.texi b/doc/guix.texi index 730b6a3770..569790065f 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -4375,12 +4375,27 @@ This command also installs GRUB on the device specified in @item vm @cindex virtual machine +@cindex VM Build a virtual machine that contain the operating system declared in @var{file}, and return a script to run that virtual machine (VM). Arguments given to the script are passed as is to QEMU. The VM shares its store with the host system. +Additional file systems can be shared between the host and the VM using +the @code{--share} and @code{--expose} command-line options: the former +specifies a directory to be shared with write access, while the latter +provides read-only access to the shared directory. + +The example below creates a VM in which the user's home directory is +accessible read-only, and where the @file{/exchange} directory is a +read-write mapping of the host's @file{$HOME/tmp}: + +@example +guix system vm my-config.scm \ + --expose=$HOME --share=$HOME/tmp=/exchange +@end example + On GNU/Linux, the default is to boot directly to the kernel; this has the advantage of requiring only a very tiny root disk image since the host's store can then be mounted. diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm index 92364fda27..398a5a371b 100644 --- a/guix/scripts/system.scm +++ b/guix/scripts/system.scm @@ -264,7 +264,7 @@ it atomically, and then run OS's activation script." ;;; (define* (system-derivation-for-action os action - #:key image-size full-boot?) + #:key image-size full-boot? mappings) "Return as a monadic value the derivation for OS according to ACTION." (case action ((build init reconfigure) @@ -274,7 +274,8 @@ it atomically, and then run OS's activation script." ((vm) (system-qemu-image/shared-store-script os #:full-boot? full-boot? - #:disk-image-size image-size)) + #:disk-image-size image-size + #:mappings mappings)) ((disk-image) (system-disk-image os #:disk-image-size image-size)))) @@ -298,7 +299,8 @@ true." (define* (perform-action action os #:key grub? dry-run? use-substitutes? device target - image-size full-boot?) + image-size full-boot? + (mappings '())) "Perform ACTION for OS. GRUB? specifies whether to install GRUB; DEVICE is the target devices for GRUB; TARGET is the target root directory; IMAGE-SIZE is the size of the image to be built, for the 'vm-image' and 'disk-image' @@ -307,7 +309,8 @@ boot directly to the kernel or to the bootloader." (mlet* %store-monad ((sys (system-derivation-for-action os action #:image-size image-size - #:full-boot? full-boot?)) + #:full-boot? full-boot? + #:mappings mappings)) (grub (package->derivation grub)) (grub.cfg (grub.cfg os)) (drvs -> (if (and grub? (memq action '(init reconfigure))) @@ -379,6 +382,10 @@ Build the operating system declared in FILE according to ACTION.\n")) --image-size=SIZE for 'vm-image', produce an image of SIZE")) (display (_ " --no-grub for 'init', do not install GRUB")) + (display (_ " + --share=SPEC for 'vm', share host file system according to SPEC")) + (display (_ " + --expose=SPEC for 'vm', expose host file system according to SPEC")) (display (_ " --full-boot for 'vm', make a full boot sequence")) (newline) @@ -389,6 +396,19 @@ Build the operating system declared in FILE according to ACTION.\n")) (newline) (show-bug-report-information)) +(define (specification->file-system-mapping spec writable?) + "Read the SPEC and return the corresponding ." + (let ((index (string-index spec #\=))) + (if index + (file-system-mapping + (source (substring spec 0 index)) + (target (substring spec (+ 1 index))) + (writable? writable?)) + (file-system-mapping + (source spec) + (target spec) + (writable? writable?))))) + (define %options ;; Specifications of the command-line options. (cons* (option '(#\h "help") #f #f @@ -408,6 +428,18 @@ Build the operating system declared in FILE according to ACTION.\n")) (option '("full-boot") #f #f (lambda (opt name arg result) (alist-cons 'full-boot? #t result))) + + (option '("share") #t #f + (lambda (opt name arg result) + (alist-cons 'file-system-mapping + (specification->file-system-mapping arg #t) + result))) + (option '("expose") #t #f + (lambda (opt name arg result) + (alist-cons 'file-system-mapping + (specification->file-system-mapping arg #f) + result))) + (option '(#\n "dry-run") #f #f (lambda (opt name arg result) (alist-cons 'dry-run? #t result))) @@ -502,6 +534,11 @@ Build the operating system declared in FILE according to ACTION.\n")) #:use-substitutes? (assoc-ref opts 'substitutes?) #:image-size (assoc-ref opts 'image-size) #:full-boot? (assoc-ref opts 'full-boot?) + #:mappings (filter-map (match-lambda + (('file-system-mapping . m) + m) + (_ #f)) + opts) #:grub? grub? #:target target #:device device) #:system system)))) -- cgit v1.2.3