diff options
| -rw-r--r-- | gnu/build/file-systems.scm | 59 |
1 files changed, 58 insertions, 1 deletions
diff --git a/gnu/build/file-systems.scm b/gnu/build/file-systems.scm index 8ec8eac896..b762e82ad2 100644 --- a/gnu/build/file-systems.scm +++ b/gnu/build/file-systems.scm @@ -3,7 +3,7 @@ ;;; Copyright © 2016, 2017 David Craven <david@craven.ch> ;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com> ;;; Copyright © 2019 Guillaume Le Vaillant <glv@posteo.net> -;;; Copyright © 2019 Tobias Geerinckx-Rice <me@tobias.gr> +;;; Copyright © 2019, 2020 Tobias Geerinckx-Rice <me@tobias.gr> ;;; Copyright © 2019 David C. Trudgian <dave@trudgian.net> ;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com> ;;; @@ -218,6 +218,58 @@ if DEVICE does not contain an linux-swap file system." "Return the label of Linux-swap superblock SBLOCK as a string." (null-terminated-latin1->string (sub-bytevector sblock (+ 1024 4 4 4 16) 16))) + + +;;; +;;; Bcachefs file systems. +;;; + +;; <https://evilpiepirate.org/git/bcachefs-tools.git/tree/libbcachefs/bcachefs_format.h> + +(define-syntax %bcachefs-endianness + ;; Endianness of bcachefs file systems. + (identifier-syntax (endianness little))) + +(define (bcachefs-superblock? sblock) + "Return #t when SBLOCK is an bcachefs superblock." + (bytevector=? (sub-bytevector sblock 24 16) + #vu8(#xc6 #x85 #x73 #xf6 #x4e #x1a #x45 #xca + #x82 #x65 #xf5 #x7f #x48 #xba #x6d #x81))) + +(define (read-bcachefs-superblock device) + "Return the raw contents of DEVICE's bcachefs superblock as a bytevector, or #f +if DEVICE does not contain a bcachefs file system." + ;; We completely ignore the back-up superblock & any checksum errors. + ;; Superblock field names, with offset & length respectively, in bytes: + ;; 0 16 bch_csum + ;; 16 8 version + ;; 24 16 magic + ;; 40 16 uuid ← ‘internal UUID’, you probably don't want this + ;; 56 16 user_uuid ← ‘external UUID’, the one by which to mount + ;; 72 32 label + ;; … there are more & the superblock is extensible, but we don't care yet. + (read-superblock device 4096 104 bcachefs-superblock?)) + +(define (bcachefs-superblock-external-uuid sblock) + "Return the external UUID of bcachefs superblock SBLOCK as a 16-byte +bytevector." + (sub-bytevector sblock 56 16)) + +(define (bcachefs-superblock-volume-name sblock) + "Return the volume name of SBLOCK as a string of at most 32 characters, or +#f if SBLOCK has no volume name." + (null-terminated-latin1->string (sub-bytevector sblock 72 32))) + +(define (check-bcachefs-file-system device) + "Return the health of a bcachefs file system on DEVICE." + (match (status:exit-val + (apply system* "bcachefs" "fsck" "-p" "-v" + ;; Make each multi-device member a separate argument. + (string-split device #\:))) + (0 'pass) + (1 'errors-corrected) + (2 'reboot-required) + (_ 'fatal-error))) ;;; @@ -638,6 +690,8 @@ partition field reader that returned a value." ext2-superblock-volume-name) (partition-field-reader read-linux-swap-superblock linux-swap-superblock-volume-name) + (partition-field-reader read-bcachefs-superblock + bcachefs-superblock-volume-name) (partition-field-reader read-btrfs-superblock btrfs-superblock-volume-name) (partition-field-reader read-fat32-superblock @@ -656,6 +710,8 @@ partition field reader that returned a value." ext2-superblock-uuid) (partition-field-reader read-linux-swap-superblock linux-swap-superblock-uuid) + (partition-field-reader read-bcachefs-superblock + bcachefs-superblock-external-uuid) (partition-field-reader read-btrfs-superblock btrfs-superblock-uuid) (partition-field-reader read-fat32-superblock @@ -763,6 +819,7 @@ containing ':/')." (define check-procedure (cond ((string-prefix? "ext" type) check-ext2-file-system) + ((string-prefix? "bcachefs" type) check-bcachefs-file-system) ((string-prefix? "btrfs" type) check-btrfs-file-system) ((string-suffix? "fat" type) check-fat-file-system) ((string-prefix? "jfs" type) check-jfs-file-system) |