diff --git a/doc/guix.texi b/doc/guix.texi index 5129b998bd..5eee40fc3c 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -9210,20 +9210,31 @@ This is a string specifying the type of the file system---e.g., This designates the place where the file system is to be mounted. @item @code{device} -This names the ``source'' of the file system. By default it is the name -of a node under @file{/dev}, but its meaning depends on the @code{title} -field described below. +This names the ``source'' of the file system. It can be one of three +things: a file system label, a file system UUID, or the name of a +@file{/dev} node. Labels and UUIDs offer a way to refer to file +systems without having to hard-code their actual device +name@footnote{Note that, while it is tempting to use +@file{/dev/disk/by-uuid} and similar device names to achieve the same +result, this is not recommended: These special device nodes are created +by the udev daemon and may be unavailable at the time the device is +mounted.}. -@item @code{title} (default: @code{'device}) -This is a symbol that specifies how the @code{device} field is to be -interpreted. +@findex file-system-label +File system labels are created using the @code{file-system-label} +procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are +plain strings. Here's an example of a file system referred to by its +label, as shown by the @command{e2label} command: -When it is the symbol @code{device}, then the @code{device} field is -interpreted as a file name; when it is @code{label}, then @code{device} -is interpreted as a file system label name; when it is @code{uuid}, -@code{device} is interpreted as a file system unique identifier (UUID). +@example +(file-system + (mount-point "/home") + (type "ext4") + (device (file-system-label "my-home"))) +@end example -UUIDs may be converted from their string representation (as shown by the +@findex uuid +UUIDs are converted from their string representation (as shown by the @command{tune2fs -l} command) using the @code{uuid} form@footnote{The @code{uuid} form expects 16-byte UUIDs as defined in @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the @@ -9235,22 +9246,13 @@ like this: (file-system (mount-point "/home") (type "ext4") - (title 'uuid) (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))) @end example -The @code{label} and @code{uuid} options offer a way to refer to file -systems without having to hard-code their actual device -name@footnote{Note that, while it is tempting to use -@file{/dev/disk/by-uuid} and similar device names to achieve the same -result, this is not recommended: These special device nodes are created -by the udev daemon and may be unavailable at the time the device is -mounted.}. - -However, when the source of a file system is a mapped device (@pxref{Mapped +When the source of a file system is a mapped device (@pxref{Mapped Devices}), its @code{device} field @emph{must} refer to the mapped -device name---e.g., @file{/dev/mapper/root-partition}---and consequently -@code{title} must be set to @code{'device}. This is required so that +device name---e.g., @file{"/dev/mapper/root-partition"}. +This is required so that the system knows that mounting the file system depends on having the corresponding device mapping established. diff --git a/gnu/bootloader/grub.scm b/gnu/bootloader/grub.scm index 3b01125c78..eca6d97b19 100644 --- a/gnu/bootloader/grub.scm +++ b/gnu/bootloader/grub.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2013, 2014, 2015, 2016, 2017 Ludovic Courtès +;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018 Ludovic Courtès ;;; Copyright © 2016 Chris Marusich ;;; Copyright © 2017 Leo Famulari ;;; Copyright © 2017 Mathieu Othacehe @@ -31,6 +31,7 @@ (define-module (gnu bootloader grub) #:use-module (gnu system) #:use-module (gnu bootloader) #:use-module (gnu system uuid) + #:use-module (gnu system file-systems) #:autoload (gnu packages bootloaders) (grub) #:autoload (gnu packages compression) (gzip) #:autoload (gnu packages gtk) (guile-cairo guile-rsvg) @@ -303,9 +304,10 @@ (define (grub-root-search device file) ((? uuid? uuid) (format #f "search --fs-uuid --set ~a" (uuid->string device))) - ((? string? label) - (format #f "search --label --set ~a" label)) - (#f + ((? file-system-label? label) + (format #f "search --label --set ~a" + (file-system-label->string label))) + ((or #f (? string?)) #~(format #f "search --file --set ~a" #$file))))) (define* (grub-configuration-file config entries diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index 145b3b14e7..3dd7358fd3 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2014, 2015, 2016, 2017 Ludovic Courtès +;;; Copyright © 2014, 2015, 2016, 2017, 2018 Ludovic Courtès ;;; Copyright © 2016, 2017 David Craven ;;; Copyright © 2017 Mathieu Othacehe ;;; @@ -473,17 +473,9 @@ (define find-partition-by-luks-uuid (find-partition luks-partition-uuid-predicate)) -(define* (canonicalize-device-spec spec #:optional (title 'any)) - "Return the device name corresponding to SPEC. TITLE is a symbol, one of -the following: - - • 'device', in which case SPEC is known to designate a device node--e.g., - \"/dev/sda1\"; - • 'label', in which case SPEC is known to designate a partition label--e.g., - \"my-root-part\"; - • 'uuid', in which case SPEC must be a UUID designating a partition; - • 'any', in which case SPEC can be anything. -" +(define (canonicalize-device-spec spec) + "Return the device name corresponding to SPEC, which can be a , a +, or a string (typically a /dev file name)." (define max-trials ;; Number of times we retry partition label resolution, 1 second per ;; trial. Note: somebody reported a delay of 16 seconds (!) before their @@ -491,19 +483,6 @@ (define max-trials ;; this long. 20) - (define canonical-title - ;; The realm of canonicalization. - (if (eq? title 'any) - (if (string? spec) - ;; The "--root=SPEC" kernel command-line option always provides a - ;; string, but the string can represent a device, a UUID, or a - ;; label. So check for all three. - (cond ((string-prefix? "/" spec) 'device) - ((string->uuid spec) 'uuid) - (else 'label)) - 'uuid) - title)) - (define (resolve find-partition spec fmt) (let loop ((count 0)) (let ((device (find-partition spec))) @@ -518,23 +497,19 @@ (define (resolve find-partition spec fmt) (sleep 1) (loop (+ 1 count)))))))) - (case canonical-title - ((device) + (match spec + ((? string?) ;; Nothing to do. spec) - ((label) + ((? file-system-label?) ;; Resolve the label. - (resolve find-partition-by-label spec identity)) - ((uuid) + (resolve find-partition-by-label + (file-system-label->string spec) + identity)) + ((? uuid?) (resolve find-partition-by-uuid - (cond ((string? spec) - (string->uuid spec)) - ((uuid? spec) - (uuid-bytevector spec)) - (else spec)) - uuid->string)) - (else - (error "unknown device title" title)))) + (uuid-bytevector spec) + uuid->string)))) (define (check-file-system device type) "Run a file system check of TYPE on DEVICE." @@ -615,8 +590,7 @@ (define (mount-nfs source mount-point type flags options) ""))))) (let ((type (file-system-type fs)) (options (file-system-options fs)) - (source (canonicalize-device-spec (file-system-device fs) - (file-system-title fs))) + (source (canonicalize-device-spec (file-system-device fs))) (mount-point (string-append root "/" (file-system-mount-point fs))) (flags (mount-flags->bit-mask (file-system-flags fs)))) diff --git a/gnu/build/linux-boot.scm b/gnu/build/linux-boot.scm index 18d87260a9..44b3506284 100644 --- a/gnu/build/linux-boot.scm +++ b/gnu/build/linux-boot.scm @@ -507,9 +507,15 @@ (define (lookup-module name) (error "pre-mount actions failed"))) (if root - (mount-root-file-system (canonicalize-device-spec root) - root-fs-type - #:volatile-root? volatile-root?) + ;; The "--root=SPEC" kernel command-line option always provides a + ;; string, but the string can represent a device, a UUID, or a + ;; label. So check for all three. + (let ((root (cond ((string-prefix? "/" root) root) + ((uuid root) => identity) + (else (file-system-label root))))) + (mount-root-file-system (canonicalize-device-spec root) + root-fs-type + #:volatile-root? volatile-root?)) (mount "none" "/root" "tmpfs")) ;; Mount the specified file systems. diff --git a/gnu/services/base.scm b/gnu/services/base.scm index eb82b2ddcf..09a1ce95e3 100644 --- a/gnu/services/base.scm +++ b/gnu/services/base.scm @@ -303,15 +303,14 @@ (define user-processes-service-type (define (file-system->fstab-entry file-system) "Return a @file{/etc/fstab} entry for @var{file-system}." - (string-append (case (file-system-title file-system) - ((label) - (string-append "LABEL=" (file-system-device file-system))) - ((uuid) - (string-append - "UUID=" - (uuid->string (file-system-device file-system)))) - (else - (file-system-device file-system))) + (string-append (match (file-system-device file-system) + ((? file-system-label? label) + (string-append "LABEL=" + (file-system-label->string file-system))) + ((? uuid? uuid) + (string-append "UUID=" (uuid->string uuid))) + ((? string? device) + device)) "\t" (file-system-mount-point file-system) "\t" (file-system-type file-system) "\t" diff --git a/gnu/system.scm b/gnu/system.scm index 1052e9355d..288c1e8801 100644 --- a/gnu/system.scm +++ b/gnu/system.scm @@ -131,13 +131,16 @@ (define (bootable-kernel-arguments kernel-arguments system.drv root-device) "Prepend extra arguments to KERNEL-ARGUMENTS that allow SYSTEM.DRV to be booted from ROOT-DEVICE" (cons* (string-append "--root=" - (if (uuid? root-device) + (cond ((uuid? root-device) - ;; Note: Always use the DCE format because that's - ;; what (gnu build linux-boot) expects for the - ;; '--root' kernel command-line option. - (uuid->string (uuid-bytevector root-device) 'dce) - root-device)) + ;; Note: Always use the DCE format because that's + ;; what (gnu build linux-boot) expects for the + ;; '--root' kernel command-line option. + (uuid->string (uuid-bytevector root-device) + 'dce)) + ((file-system-label? root-device) + (file-system-label->string root-device)) + (else root-device))) #~(string-append "--system=" #$system.drv) #~(string-append "--load=" #$system.drv "/boot") kernel-arguments)) @@ -251,10 +254,16 @@ (define device-sexp->device (match-lambda (('uuid (? symbol? type) (? bytevector? bv)) (bytevector->uuid bv type)) + (('file-system-label (? string? label)) + (file-system-label label)) ((? bytevector? bv) ;old format (bytevector->uuid bv 'dce)) ((? string? device) - device))) + ;; It used to be that we would not distinguish between labels and + ;; device names. Try to infer the right thing here. + (if (string-prefix? "/dev/" device) + device + (file-system-label device))))) (match (read port) (('boot-parameters ('version 0) @@ -377,7 +386,7 @@ (define (mapped-device-user device file-systems) (let ((target (string-append "/dev/mapper/" (mapped-device-target device)))) (find (lambda (fs) (or (member device (file-system-dependencies fs)) - (and (eq? 'device (file-system-title fs)) + (and (string? (file-system-device fs)) (string=? (file-system-device fs) target)))) file-systems))) @@ -934,13 +943,6 @@ (define* (operating-system-bootcfg os #:optional (old-entries '())) (bootloader-configuration-bootloader bootloader-conf)) bootloader-conf (list entry) #:old-entries old-entries))) -(define (fs->boot-device fs) - "Given FS, a object, return a value suitable for use as the -device in a ." - (case (file-system-title fs) - ((uuid label device) (file-system-device fs)) - (else #f))) - (define (operating-system-boot-parameters os system.drv root-device) "Return a monadic record that describes the boot parameters of OS. SYSTEM.DRV is either a derivation or #f. If it's a derivation, adds @@ -962,7 +964,7 @@ (define (operating-system-boot-parameters os system.drv root-device) (operating-system-user-kernel-arguments os))) (initrd initrd) (bootloader-name bootloader-name) - (store-device (ensure-not-/dev (fs->boot-device store))) + (store-device (ensure-not-/dev (file-system-device store))) (store-mount-point (file-system-mount-point store)))))) (define (device->sexp device) @@ -970,6 +972,8 @@ (define (device->sexp device) (match device ((? uuid? uuid) `(uuid ,(uuid-type uuid) ,(uuid-bytevector uuid))) + ((? file-system-label? label) + `(file-system-label ,(file-system-label->string label))) (_ device))) diff --git a/gnu/system/examples/bare-bones.tmpl b/gnu/system/examples/bare-bones.tmpl index 7e0c8fbee0..cb6d2623db 100644 --- a/gnu/system/examples/bare-bones.tmpl +++ b/gnu/system/examples/bare-bones.tmpl @@ -16,8 +16,7 @@ (bootloader grub-bootloader) (target "/dev/sdX"))) (file-systems (cons (file-system - (device "my-root") - (title 'label) + (device (file-system-label "my-root")) (mount-point "/") (type "ext4")) %base-file-systems)) diff --git a/gnu/system/examples/beaglebone-black.tmpl b/gnu/system/examples/beaglebone-black.tmpl index 97201330c7..d1130c76b6 100644 --- a/gnu/system/examples/beaglebone-black.tmpl +++ b/gnu/system/examples/beaglebone-black.tmpl @@ -20,8 +20,7 @@ (initrd-modules (cons "omap_hsmmc" %base-initrd-modules)) (file-systems (cons (file-system - (device "my-root") - (title 'label) + (device (file-system-label "my-root")) (mount-point "/") (type "ext4")) %base-file-systems)) diff --git a/gnu/system/examples/lightweight-desktop.tmpl b/gnu/system/examples/lightweight-desktop.tmpl index 65a8ee1809..360ee62ffe 100644 --- a/gnu/system/examples/lightweight-desktop.tmpl +++ b/gnu/system/examples/lightweight-desktop.tmpl @@ -20,13 +20,11 @@ ;; Assume the target root file system is labelled "my-root", ;; and the EFI System Partition has UUID 1234-ABCD. (file-systems (cons* (file-system - (device "my-root") - (title 'label) + (device (file-system-label "my-root")) (mount-point "/") (type "ext4")) (file-system (device (uuid "1234-ABCD" 'fat)) - (title 'uuid) (mount-point "/boot/efi") (type "vfat")) %base-file-systems)) diff --git a/gnu/system/examples/vm-image.tmpl b/gnu/system/examples/vm-image.tmpl index ce3653c8b4..36e272722d 100644 --- a/gnu/system/examples/vm-image.tmpl +++ b/gnu/system/examples/vm-image.tmpl @@ -31,8 +31,7 @@ partprobe, and then 2) resizing the filesystem with resize2fs.\n")) (target "/dev/sda") (terminal-outputs '(console)))) (file-systems (cons (file-system - (device "my-root") - (title 'label) + (device (file-system-label "my-root")) (mount-point "/") (type "ext4")) %base-file-systems)) diff --git a/gnu/system/file-systems.scm b/gnu/system/file-systems.scm index 93289dbd5d..2b5948256a 100644 --- a/gnu/system/file-systems.scm +++ b/gnu/system/file-systems.scm @@ -20,6 +20,8 @@ (define-module (gnu system file-systems) #:use-module (ice-9 match) #:use-module (rnrs bytevectors) #:use-module (srfi srfi-1) + #:use-module (srfi srfi-9) + #:use-module (srfi srfi-9 gnu) #:use-module (guix records) #:use-module (gnu system uuid) #:re-export (uuid ;backward compatibility @@ -28,7 +30,7 @@ (define-module (gnu system file-systems) #:export (file-system file-system? file-system-device - file-system-title + file-system-title ;deprecated file-system-mount-point file-system-type file-system-needed-for-boot? @@ -42,6 +44,10 @@ (define-module (gnu system file-systems) file-system-type-predicate + file-system-label + file-system-label? + file-system-label->string + file-system->spec spec->file-system specification->file-system-mapping @@ -82,12 +88,10 @@ (define-module (gnu system file-systems) ;;; Code: ;; File system declaration. -(define-record-type* file-system +(define-record-type* %file-system make-file-system file-system? - (device file-system-device) ; string - (title file-system-title ; 'device | 'label | 'uuid - (default 'device)) + (device file-system-device) ; string | | (mount-point file-system-mount-point) ; string (type file-system-type) ; string (flags file-system-flags ; list of symbols @@ -108,6 +112,83 @@ (define-record-type* file-system (default (current-source-location)) (innate))) +;; A file system label for use in the 'device' field. +(define-record-type + (file-system-label label) + file-system-label? + (label file-system-label->string)) + +(set-record-type-printer! + (lambda (obj port) + (format port "#" + (file-system-label->string obj)))) + +(define-syntax report-deprecation + (lambda (s) + "Report the use of the now-deprecated 'title' field." + (syntax-case s () + ((_ field) + (let* ((source (syntax-source #'field)) + (file (and source (assq-ref source 'filename))) + (line (and source + (and=> (assq-ref source 'line) 1+))) + (column (and source (assq-ref source 'column)))) + (format (current-error-port) + "~a:~a:~a: warning: 'title' field is deprecated~%" + file line column) + #t))))) + +;; Helper for 'process-file-system-declaration'. +(define-syntax device-expression + (syntax-rules (quote label uuid device) + ((_ (quote label) dev) + (file-system-label dev)) + ((_ (quote uuid) dev) + (if (uuid? dev) dev (uuid dev))) + ((_ (quote device) dev) + dev) + ((_ title dev) + (case title + ((label) (file-system-label dev)) + ((uuid) (uuid dev)) + (else dev))))) + +;; Helper to interpret the now-deprecated 'title' field. Detect forms like +;; (title 'label), remove them, and adjust the 'device' field accordingly. +;; TODO: Remove this once 'title' has been deprecated long enough. +(define-syntax process-file-system-declaration + (syntax-rules (device title) + ((_ () (rest ...) #f #f) ;no 'title' and no 'device' field + (%file-system rest ...)) + ((_ () (rest ...) dev #f) ;no 'title' field + (%file-system rest ... (device dev))) + ((_ () (rest ...) dev titl) ;got a 'title' field + (%file-system rest ... + (device (device-expression titl dev)))) + ((_ ((title titl) rest ...) (previous ...) dev _) + (begin + (report-deprecation (title titl)) + (process-file-system-declaration (rest ...) + (previous ...) + dev titl))) + ((_ ((device dev) rest ...) (previous ...) _ titl) + (process-file-system-declaration (rest ...) + (previous ...) + dev titl)) + ((_ (field rest ...) (previous ...) dev titl) + (process-file-system-declaration (rest ...) + (previous ... field) + dev titl)))) + +(define-syntax-rule (file-system fields ...) + (process-file-system-declaration (fields ...) () #f #f)) + +(define (file-system-title fs) ;deprecated + (match (file-system-device fs) + ((? file-system-label?) 'label) + ((? uuid?) 'uuid) + ((? string?) 'device))) + ;; Note: This module is used both on the build side and on the host side. ;; Arrange not to pull (guix store) and (guix config) because the latter ;; differs from user to user. @@ -160,23 +241,26 @@ (define (file-system->spec fs) "Return a list corresponding to file-system FS that can be passed to the initrd code." (match fs - (($ device title mount-point type flags options _ _ check?) - (list (if (uuid? device) - `(uuid ,(uuid-type device) ,(uuid-bytevector device)) - device) - title mount-point type flags options check?)))) + (($ device mount-point type flags options _ _ check?) + (list (cond ((uuid? device) + `(uuid ,(uuid-type device) ,(uuid-bytevector device))) + ((file-system-label? device) + `(file-system-label ,(file-system-label->string device))) + (else device)) + mount-point type flags options check?)))) (define (spec->file-system sexp) "Deserialize SEXP, a list, to the corresponding object." (match sexp - ((device title mount-point type flags options check?) + ((device mount-point type flags options check?) (file-system (device (match device (('uuid (? symbol? type) (? bytevector? bv)) (bytevector->uuid bv type)) + (('file-system-label (? string? label)) + (file-system-label label)) (_ device))) - (title title) (mount-point mount-point) (type type) (flags flags) (options options) (check? check?))))) diff --git a/gnu/system/vm.scm b/gnu/system/vm.scm index eb73b5ca7a..7f80147150 100644 --- a/gnu/system/vm.scm +++ b/gnu/system/vm.scm @@ -693,13 +693,12 @@ (define user-file-systems (source (file-system-device fs))) (or (string=? target (%store-prefix)) (string=? target "/") - (and (eq? 'device (file-system-title fs)) + (and (string? source) (string-prefix? "/dev/" source)) ;; Labels and UUIDs are necessarily invalid in the VM. (and (file-system-mount? fs) - (or (eq? 'label (file-system-title fs)) - (eq? 'uuid (file-system-title fs)) + (or (file-system-label? source) (uuid? source)))))) (operating-system-file-systems os))) diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm index af501eb8f7..5d0df14924 100644 --- a/guix/scripts/system.scm +++ b/guix/scripts/system.scm @@ -590,17 +590,17 @@ (define relevant (define labeled (filter (lambda (fs) - (eq? (file-system-title fs) 'label)) + (file-system-label? (file-system-device fs))) relevant)) (define literal (filter (lambda (fs) - (eq? (file-system-title fs) 'device)) + (string? (file-system-device fs))) relevant)) (define uuid (filter (lambda (fs) - (eq? (file-system-title fs) 'uuid)) + (uuid? (file-system-device fs))) relevant)) (define fail? #f) @@ -628,15 +628,15 @@ (define (file-system-location* fs) (strerror errno)) (unless (string-prefix? "/" device) (display-hint (format #f (G_ "If '~a' is a file system -label, you need to add @code{(title 'label)} to your @code{file-system} -definition.") - device))))))) +label, write @code{(file-system-label ~s)} in your @code{device} field.") + device device))))))) literal) (for-each (lambda (fs) - (unless (find-partition-by-label (file-system-device fs)) - (error (G_ "~a: error: file system with label '~a' not found~%") - (file-system-location* fs) - (file-system-device fs)))) + (let ((label (file-system-label->string + (file-system-device fs)))) + (unless (find-partition-by-label label) + (error (G_ "~a: error: file system with label '~a' not found~%") + (file-system-location* fs) label)))) labeled) (for-each (lambda (fs) (unless (find-partition-by-uuid (file-system-device fs)) @@ -677,10 +677,13 @@ (define (check-initrd-modules os) checking this by themselves in their 'check' procedure." (define (file-system-/dev fs) (let ((device (file-system-device fs))) - (match (file-system-title fs) - ('device device) - ('uuid (find-partition-by-uuid device)) - ('label (find-partition-by-label device))))) + (match device + ((? string?) + device) + ((? uuid?) + (find-partition-by-uuid device)) + ((? file-system-label?) + (find-partition-by-label (file-system-label->string device)))))) (define file-systems (filter file-system-needed-for-boot?