The host bridge now carries MMIO apertures derived from the boot memory
map's gaps below 4 GiB (largest three, sort-merged; a single after-the-
last-region hole dies on OVMF's flash at the top) plus one aperture above
the described space — so a user-space device_register of PCI functions
with BAR resources can pass containment. The discovery test asserts
every PCI memory resource lies inside a bridge window and names any
escapee. device_register is idempotent on exact (parent, class, identity,
resources) match — a restarted registering bus cannot duplicate its
children; proven directly against the broker in the bus test.
ChildAdded gains device_id so a report can carry the registered kernel
id a matched driver needs as its assignment.
Every path out of a process (exit, fault, kill) now releases its device
claims alongside its IRQ and MSI bindings, so a restarted driver can claim
its hardware again — the cleanup half of process-lifecycle.md's iron rule 1.
MSI vectors were already swept by irq.releaseOwner; claims were the gap.
The claim-release test proves kill -> release -> re-claim, plus the broker
release in isolation.
The `system` module (formerly `danos`) had become a grab-bag: it held the
loader<->kernel handoff *and* the kernel<->user ABI *and* the device wire types, in
one module three different audiences imported. Usage proved the seam — the
bootloader never touched the syscall/device ABI, and user space never touched the
boot handoff — so split it by audience, one module per contract:
system/boot-handoff.zig loader <-> kernel: BootInformation, Framebuffer,
MemoryMap, the VM layout + physicalToVirtual, kernel_abi
system/abi.zig kernel <-> user, core: SystemCall, mmap prot flags,
page_size, notify_badge_bit, ServiceId
system/devices/device-abi.zig kernel <-> user, devices: DeviceDescriptor,
DeviceClass, ResourceDescriptor, ResourceKind, ...
device-abi is the devices sub-project's public interface, exposed as its own module
the way vfs exposes vfs-protocol — importable by user space, unlike the
kernel-internal device model it also feeds. That collapses a real duplication:
DeviceClass and ResourceKind were defined twice (device-model.zig and the contract,
kept "in sync by hand"); device-model now re-exports them from device-abi, so the
enum a driver matches on and the one the kernel classifies with are one type.
Each import now declares which contract it speaks: the bootloader imports only
boot-handoff; a driver only abi + device-abi (via the runtime); the kernel all
three. This also retires the `system` / `runtime.system` name overlap. page_size
lands in abi (it's part of the mmap contract user space aligns to); the bootloader
keeps its own local 4 KiB constant so it depends on nothing but the handoff.
All 21 importers rewired, docs updated to keep /system mapping to source. Build,
host tests, and the QEMU suite (36/36) all green.
The shared kernel<->user ABI contract (BootInformation, the SystemCall numbers,
DeviceDescriptor, page_size, ...) is now the `system` module at
system/system.zig, following the convention that a directory's root file takes
the directory's name.
One overlap to note: the runtime's syscall wrappers are already `runtime.system`,
so the single file that uses both the contract and those wrappers
(library/runtime/heap.zig) aliases the wrappers locally as `system_calls`. The
two are distinct (top-level `system` vs `runtime.system`); everywhere else the
contract is just `system`.
Also: the QEMU run's serial capture now lands in the FHS log location,
zig-out/var/log/system/serial0-<timestamp>.log — a stand-in for the kernel's own
logging system, which will eventually write there itself.
Suite 35/35 plus host tests green.
Follow-up to the monorepo re-org. Suite 35/35 plus host tests green.
POSIX compatibility is now its own library, library/posix/ (unistd, stdio),
layered strictly over the runtime — it calls the runtime's IPC/heap, never
system calls directly. The runtime is now POSIX-free (the danos-native
application ABI). The VFS wire protocol is danos-native throughout
(Stat -> FileStatus, .stat -> .status, O_CREAT -> create); the POSIX layer
maps the POSIX spellings at the boundary. The coding standard's ABI-name
exception is scoped to one place: a file is allowed POSIX spellings only if it
lives under library/posix/ — everywhere else, danos naming with no exception.
Naming fixes, all mechanical:
- initrd -> initial-ramdisk: the source file, the module, the tool
(make-initial-ramdisk.py), the artifact (initial-ramdisk.img, including the
bootloader's load path), and the identifiers.
- system/kernel/device-service.zig -> devices-broker.zig: it is ring-0 kernel
code (the trusted device table + claim capability), not a ring-3 service. The
future user-space device *manager* (policy) will live in system/services/.
- Dropped the daemon `d` suffix: hpetd -> hpet, busd -> bus. A driver lives in
system/drivers/, so the folder already says what it is; encoding the role in
the name too is redundant. The coding standard drops that exception.
- system/devices/aml/interp.zig -> interpreter.zig (the type was already
Interpreter).
Daniel Samson