diff options
Diffstat (limited to 'gnu/build')
| -rw-r--r-- | gnu/build/linux-boot.scm | 43 |
1 files changed, 13 insertions, 30 deletions
diff --git a/gnu/build/linux-boot.scm b/gnu/build/linux-boot.scm index 3712abe910..a1ff4dd1ea 100644 --- a/gnu/build/linux-boot.scm +++ b/gnu/build/linux-boot.scm @@ -241,20 +241,10 @@ the last argument of `mknod'." (filter-map string->number (scandir "/proc"))))) (define* (mount-root-file-system root type - #:key volatile-root? (unionfs "unionfs")) + #:key volatile-root?) "Mount the root file system of type TYPE at device ROOT. If VOLATILE-ROOT? -is true, mount ROOT read-only and make it a union with a writable tmpfs using -UNIONFS." - (define (mark-as-not-killable pid) - ;; Tell the 'user-processes' shepherd service that PID must be kept alive - ;; when shutting down. - (mkdir-p "/root/etc/shepherd") - (let ((port (open-file "/root/etc/shepherd/do-not-kill" "a"))) - (chmod port #o600) - (write pid port) - (newline port) - (close-port port))) - +is true, mount ROOT read-only and make it a overlay with a writable tmpfs +using the kernel build-in overlayfs." (if volatile-root? (begin (mkdir-p "/real-root") @@ -262,24 +252,17 @@ UNIONFS." (mkdir-p "/rw-root") (mount "none" "/rw-root" "tmpfs") + ;; Create the upperdir and the workdir of the overlayfs + (mkdir-p "/rw-root/upper") + (mkdir-p "/rw-root/work") + ;; We want read-write /dev nodes. - (mkdir-p "/rw-root/dev") - (mount "none" "/rw-root/dev" "devtmpfs") - - ;; Make /root a union of the tmpfs and the actual root. Use - ;; 'max_files' to set a high RLIMIT_NOFILE for the unionfs process - ;; itself. Failing to do that, we quickly run out of file - ;; descriptors; see <http://bugs.gnu.org/17827>. - (unless (zero? (system* unionfs "-o" - "cow,allow_other,use_ino,suid,dev,max_files=65536" - "/rw-root=RW:/real-root=RO" - "/root")) - (error "unionfs failed")) - - ;; Make sure unionfs remains alive till the end. Because - ;; 'fuse_daemonize' doesn't tell the PID of the forked daemon, we - ;; have to resort to 'pidof' here. - (mark-as-not-killable (pidof unionfs))) + (mkdir-p "/rw-root/upper/dev") + (mount "none" "/rw-root/upper/dev" "devtmpfs") + + ;; Make /root an overlay of the tmpfs and the actual root. + (mount "none" "/root" "overlay" 0 + "lowerdir=/real-root,upperdir=/rw-root/upper,workdir=/rw-root/work")) (begin (check-file-system root type) (mount root "/root" type))) |