Btrfs migration 4: build stamping#98
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Please split out the fixups to motd and set-hostname-and-banner.sh into a separate commit directly on top of the dev branch and let us merge it, as it's not tied to the Btrfs logic.
For the build ID though - we can't record it at the rootfs generation stage, because a rootfs can be reused in multiple builds when e.g. only U-Boot changes between them, meaning that all the later builds will record an incorrect build ID. Let's give it more thought.
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Agreed, done. I'll keep this as draft until we figure out better solution. Thanks! |
Define the subvolume layout (@, @home, @var-log, @var-cache, @snapshots, boot) with per-subvolume mount options, keep /boot uncompressed so U-Boot can read the kernel/dtb/initrd, and factor out root device retrieval into a helper. Generate the BLS boot entries, deriving the devicetreedir/overlay prefix from each entry's root subvolume so U-Boot resolves the in-entry paths correctly, with FDT_SUBVOL_PREFIX as an override. Install btrfs-progs and btrfs-compsize.
journald's append-heavy writes fragment badly under btrfs copy-on-write. Pre-create the journal directory with NODATACOW while it is still empty so the journal files written on first boot inherit it.
Once the rootfs and kernel are fully deployed, take a read-only snapshot of @ into .snapshots/@_Factory-Image for rollback. It captures @ only; the nested subvolumes (boot/home/var-*) are separate and excluded.
Build a read-only @Minimal_stock golden base, then derive one read-only @<Profile>_stock per profile (Desktop, TV-Media-Box, Router) and a writable @<Profile> snapshot of each. @minimal itself is re-created as a writable child of @Minimal_stock so it matches the other profiles instead of being the parentless build origin. Profile-specific overlays move under overlays/profile-<name>/, and profile naming is finalised (stock bases, Desktop replaces KDE).
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Capture this image build's git state and a BUILD_ID (CI-provided, or a UTC timestamp fallback) and write both into /etc/os-release of @minimal before it is snapshotted to @Minimal_stock, so every profile inherits them via COW. Resolve the os-release symlink so the real file is edited in place. The MOTD and login banner now report the build ID instead of a decoded timestamp.
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Build stamping for the image (depends on #96).
BUILD_ID(CI-provided, or a UTC timestamp fallback) and write both into/etc/os-releaseof@Minimalbefore it is snapshotted to@Minimal_stock, so every profile inherits them via COW.os-releasesymlink so the real file is edited in place.Stack (merge bottom-up)
btrfs-foundation->devbtrfs-profiles->btrfs-foundationcog-kodi-display->btrfs-profilesbuild-stamping->btrfs-profiles(this PR)