The flip that makes the mount path the volume's content id. fat retires its
hardcoded fat_mounts: it reads its mount path from argv[2] (the volume manager
hands it the id-path, e.g. /volumes/fat-12345678, from the FAT serial), mounts
its volume root there, and installs the /system/configuration + /system/logs FHS
rewrites so /system/logs persistence stays decoupled from which volume backs it.
The rewrites are unconditional this increment (the single volume IS the boot
volume); S3 makes them content-conditional across N volumes. Every /volumes/usb
reference migrates to /volumes/fat-12345678 in one commit — the fat-test,
badge-scope-test, and vfs-test fixtures and the four QEMU regexes — plus a new
volume-identity-name case asserting the id-path mount and the /system/logs
rewrite. Discrimination: the regexes now require /volumes/fat-12345678, which the
old hardcoded fat never emitted (it mounted /volumes/usb). Full suite 128/128.
fs_unmount was gated by nothing but the /protocol carve-out: any process
could unmount any prefix — latent with one mount owner, an obvious
cross-tenant hole once volumes multiply. Each backend mount now records the
mounting task, and the syscall layer enforces two rules that keep the
restart story intact: only the owner unmounts (a dead owner's mount is
swept lazily by resolution — strangers gain nothing by racing that), and a
mount may be REPLACED only by its live owner or after its owner died (the
respawned-filesystem path; displacement of a live mount would be worse than
unmounting it). Kernel-installed mounts are never displaceable.
The vfs-test park role is the discrimination: with the volume provably
mounted it attempts the foreign unmount, requires the refusal AND the
subtree still resolving, and withholds its "parked" marker otherwise —
against the ungated kernel the unmount was ALLOWED and vfs-client-death
fails; with the gate, green. (Its verification handle closes immediately:
the kernel test string-matches "released 1 handle(s)".)
/etc/init.csv and /etc/devices.csv become /system/configuration/*.csv (the
repo's etc/ moves to system/configuration/, mirroring the runtime tree),
/var/log becomes /system/logs, and /mnt/usb becomes /volumes/usb. The
kernel VFS gains a carve-out so FAT may serve exactly /system/configuration
and /system/logs beneath the initrd-backed /system while /system and /test
themselves stay unshadowable; FAT's single /var mount splits into those two
rewritten mounts. The kvfs readdir check learns /system's third child and
the ramdisk spawn sweep skips the configuration tree.
Suite 106/106.
The module-to-domain table in build-support duplicated what each
domain's build.zig already states with its addModule exports. userBinary
now resolves each named import by searching the packages the binary
declared in its own build.zig.zon (b.available_deps), which also makes
the zon the literal include path: an import can only be satisfied by a
domain the binary claims, and naming a module whose domain is missing
fails the build graph with the domain to declare. build-support is down
to the recipe alone. All build variants green; manifest unchanged.
Every binary's build.zig now names precisely the modules its source
imports (derived by scanning each artifact's sources, transitively
through same-directory files), and its zon carries only the domains
those come from — kernel stays implicit (the root shim + link script
live there). build-support's userBinary resolves each name through one
module-to-domain table (module_homes); Domains/domains()/defaultImports
and the raw recipe entry point are deleted. An undeclared @import is a
compile error (verified: injecting @import("xkeyboard-config") into
logger fails with 'no module named ... available within module
program'), and e.g. xkeyboard-config now appears in exactly two
manifests — the two keyboard drivers. Availability never bloated the
emitted binaries (Zig compiles only what a program imports); this makes
the declared interfaces honest. Production and -Dtest-case manifests
byte-identical; all build variants and standalone package builds
green.
init, fat, display, display-demo, device-manager, input, logger, and
the two discovery fillers (acpi, fdt — each exporting an artifact named
"discovery"; the root -Ddiscovery picks which ships) convert to binary
packages on the pci-bus template. init's serial heartbeat flag rides
the dependency options (the root forwards its -Dserial). fat's and
display's unit tests move into their packages and the root aggregate
delegates to them. Boot-image file list unchanged.
The 11 QEMU-suite fixtures lived mixed into system/services/ with their
binaries bundled at /system/tests/<name>. Now the repo path is the boot
path, like every real service: test/system/services/<name>. fat-test
moves out of the fat server's directory into its own; display-demo
stays a boot service.
- kernel VFS: setInitialRamdisk derives one read-only initrd mount per
top-level tree named by the ramdisk entry paths (/system, /test),
registers ancestors generically with self-parented roots, and refuses
backend shadowing of any initrd tree
- EFI loader: the fallback walk also enumerates \test (optional — a
volume without fixtures still boots); manifest and capsule unchanged
- path literals: vfs-test self-open + create probe, process-test
process_enumerate matches, the args-echo argv[0] expectation; the
kvfs case now covers the /test root end to end
- docs: DFHS /test rows, tree diagrams, loader prose, and the location
convention gain the third home; fixed the input-source link
100/100 QEMU cases pass.
Daniel Samson