From de1c158f32e1d4060daa600a62b68fe22b613424 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Mon, 22 Sep 2014 11:06:42 +0200 Subject: system: Add support for boot-time mapped devices. * gnu/build/linux-boot.scm (boot-system): Add #:pre-mount parameter and honor it. * gnu/system/linux-initrd.scm (base-initrd): Add #:mapped-devices parameter. Add 'device-mapping-commands' variable, and use it to build the #:pre-mount argument of 'boot-system'. * gnu/system.scm (mapped-device-user, operating-system-user-mapped-devices, operating-system-boot-mapped-devices): New procedures. (device-mapping-services): Use 'operating-system-user-mapped-devices' instead of 'operating-system-mapped-devices'. (operating-system-initrd-file): Call the initrd with #:mapped-devices. --- gnu/build/linux-boot.scm | 12 +++++++++--- gnu/system.scm | 42 +++++++++++++++++++++++++++++++++++++----- gnu/system/linux-initrd.scm | 16 +++++++++++++++- 3 files changed, 61 insertions(+), 9 deletions(-) (limited to 'gnu') diff --git a/gnu/build/linux-boot.scm b/gnu/build/linux-boot.scm index 56042da8f6..a58232c815 100644 --- a/gnu/build/linux-boot.scm +++ b/gnu/build/linux-boot.scm @@ -340,13 +340,14 @@ bailing out.~%root contents: ~s~%" (scandir "/")) (linux-modules '()) qemu-guest-networking? volatile-root? + pre-mount (mounts '())) "This procedure is meant to be called from an initrd. Boot a system by first loading LINUX-MODULES (a list of absolute file names of '.ko' files), then setting up QEMU guest networking if QEMU-GUEST-NETWORKING? is true, -mounting the file systems specified in MOUNTS, and finally booting into the -new root if any. The initrd supports kernel command-line options '--load', -'--root', and '--repl'. +calling PRE-MOUNT, mounting the file systems specified in MOUNTS, and finally +booting into the new root if any. The initrd supports kernel command-line +options '--load', '--root', and '--repl'. Mount the root file system, specified by the '--root' command-line argument, if any. @@ -403,6 +404,11 @@ to it are lost." (mkdir "/root/dev") (make-essential-device-nodes #:root "/root")) + (when (procedure? pre-mount) + ;; Do whatever actions are needed before mounting--e.g., installing + ;; device mappings. + (pre-mount)) + ;; Mount the specified file systems. (for-each mount-file-system (remove root-mount-point? mounts)) diff --git a/gnu/system.scm b/gnu/system.scm index 13b461c003..d15c864384 100644 --- a/gnu/system.scm +++ b/gnu/system.scm @@ -216,6 +216,34 @@ as 'needed-for-boot'." #:flags flags)))) file-systems))) +(define (mapped-device-user device file-systems) + "Return a file system among FILE-SYSTEMS that uses DEVICE, or #f." + (let ((target (string-append "/dev/mapper/" (mapped-device-target device)))) + (find (lambda (fs) + (string=? (file-system-device fs) target)) + file-systems))) + +(define (operating-system-user-mapped-devices os) + "Return the subset of mapped devices that can be installed in +user-land--i.e., those not needed during boot." + (let ((devices (operating-system-mapped-devices os)) + (file-systems (operating-system-file-systems os))) + (filter (lambda (md) + (let ((user (mapped-device-user md file-systems))) + (or (not user) + (not (file-system-needed-for-boot? user))))) + devices))) + +(define (operating-system-boot-mapped-devices os) + "Return the subset of mapped devices that must be installed during boot, +from the initrd." + (let ((devices (operating-system-mapped-devices os)) + (file-systems (operating-system-file-systems os))) + (filter (lambda (md) + (let ((user (mapped-device-user md file-systems))) + (and user (file-system-needed-for-boot? user)))) + devices))) + (define (device-mapping-services os) "Return the list of device-mapping services for OS as a monadic list." (sequence %store-monad @@ -228,7 +256,7 @@ as 'needed-for-boot'." (device-mapping-service target (open source target) (close source target)))) - (operating-system-mapped-devices os)))) + (operating-system-user-mapped-devices os)))) (define (swap-services os) "Return the list of swap services for OS as a monadic list." @@ -561,10 +589,14 @@ we're running in the final root." boot?)) (operating-system-file-systems os))) - ;; TODO: Pass the mapped devices required by boot-time file systems to the - ;; initrd. - (mlet %store-monad - ((initrd ((operating-system-initrd os) boot-file-systems))) + (define mapped-devices + (operating-system-boot-mapped-devices os)) + + (define make-initrd + (operating-system-initrd os)) + + (mlet %store-monad ((initrd (make-initrd boot-file-systems + #:mapped-devices mapped-devices))) (return #~(string-append #$initrd "/initrd")))) (define (kernel->grub-label kernel) diff --git a/gnu/system/linux-initrd.scm b/gnu/system/linux-initrd.scm index cb04644053..d1b1216f9d 100644 --- a/gnu/system/linux-initrd.scm +++ b/gnu/system/linux-initrd.scm @@ -126,14 +126,16 @@ initrd code." (define* (base-initrd file-systems #:key + (mapped-devices '()) qemu-networking? virtio? volatile-root? (extra-modules '())) - ;; TODO: Support boot-time device mappings. "Return a monadic derivation that builds a generic initrd. FILE-SYSTEMS is a list of file-systems to be mounted by the initrd, possibly in addition to the root file system specified on the kernel command line via '--root'. +MAPPED-DEVICES is a list of device mappings to realize before FILE-SYSTEMS are +mounted. When QEMU-NETWORKING? is true, set up networking with the standard QEMU parameters. When VIRTIO? is true, load additional modules so the initrd can @@ -191,6 +193,16 @@ loaded at boot time in the order in which they appear." (list unionfs-fuse/static) '()))) + (define device-mapping-commands + ;; List of gexps to open the mapped devices. + (map (lambda (md) + (let* ((source (mapped-device-source md)) + (target (mapped-device-target md)) + (type (mapped-device-type md)) + (open (mapped-device-kind-open type))) + (open source target))) + mapped-devices)) + (mlet %store-monad ((kodir (flat-linux-module-directory linux-libre linux-modules))) (expression->initrd @@ -205,6 +217,8 @@ loaded at boot time in the order in which they appear." '#$helper-packages))) (boot-system #:mounts '#$(map file-system->spec file-systems) + #:pre-mount (lambda () + (and #$@device-mapping-commands)) #:linux-modules (map (lambda (file) (string-append #$kodir "/" file)) '#$linux-modules) -- cgit 1.4.1