Files
danos/lib/runtime.zig
T
Daniel Samson 15b70856c9 M11–M12: IRQ-as-IPC and bus drivers; expand names tree-wide
Two driver-model milestones plus a tree-wide naming pass. Suite 35/35
(QEMU) + host tests green.

M11 — IRQ-as-IPC. A ring-3 driver now sleeps until its device interrupts
it. New src/kernel/irq.zig: per-GSI endpoint bindings, comptime per-vector
trampolines, dispatch = mask GSI -> LAPIC EOI -> notifyLocked, all under one
lock region. irq_bind/irq_ack syscalls, gated by the device claim like
mmio_map. interruptDispatch no longer EOIs — each handler owns its EOI,
because a level line must be masked before it is acknowledged (irq_ack is
the unmask). Bindings are keyed on the owning task and released on exit
(a shared endpoint's siblings survive). hpetd rewritten interrupt-driven.
Tests: hpet (rewritten, reads back the I/O APIC routing) and irqfree.

M12 — bus drivers. DeviceDesc gains a parent, making the device table a
tree. dev_register (device_register) lets a process publish children below
a device it claimed; the kernel enforces resource containment (a child's
resources must nest in its parent's), so a descriptor can't fabricate a
window over kernel RAM. Descriptor copied in via copyFromUser (physmap
walk — an unmapped user pointer fails the call instead of faulting the
kernel). Per-parent child cap bounds table exhaustion. sbin/busd.zig is a
worked bus driver. Test: bus.

Naming — per docs/coding-standards.md: non-acronym abbreviations spelled
out (message, descriptor, device_service, scheduler, runtime, physical,
interpreter, ...); acronyms kept (IPC, MMIO, DMA, HCD, ...); files are
kebab-case (ipc-synchronous.zig, device-service.zig, vfs-protocol.zig, ...).
Exceptions: POSIX/C ABI names and Zig idioms (init/len/ptr) kept. Module
collisions resolved by specific naming (config -> parameters, device.zig
alias -> device_model). AML op/Op disambiguated: op = opcode, Op =
operation; per-opcode parse handlers renamed opX -> parseX.

New driver docs: drivers.md, driver-model.md (bus/class/HCD shapes + the
proposed M13–M16 ABI), coding-standards.md.
2026-07-10 11:39:56 +01:00

31 lines
1.4 KiB
Zig

//! danos user-space runtime library — a nascent libc. Every user binary (init,
//! and later the VFS server + device drivers) imports this as `@import("runtime")`:
//! system_call wrappers, the C-convention heap, IPC helpers, and the process start
//! shim. It is compiled into each binary (inheriting its `.large` code model and
//! freestanding target), so all user programs share one implementation.
//!
//! A user binary needs three lines:
//! const runtime = @import("runtime");
//! pub const panic = runtime.panic;
//! comptime { _ = &runtime.start._start; } // pull the entry shim in
//! and a `pub fn main() void`.
pub const system = @import("system.zig");
pub const heap = @import("heap.zig");
pub const ipc = @import("ipc.zig");
pub const start = @import("start.zig");
/// The VFS wire protocol (shared with the VFS server).
pub const vfs_protocol = @import("vfs-protocol.zig");
/// POSIX-style file API: open/read/write/lseek/stat/close.
pub const unistd = @import("unistd.zig");
/// C stdio: fopen/fread/fwrite/fseek/ftell/fclose over unistd.
pub const stdio = @import("stdio.zig");
/// Device access for drivers: enumerate/claim/mmioMap.
pub const device = @import("device.zig");
/// Re-exported so a user binary can `pub const panic = runtime.panic;`.
pub const panic = start.panic;
/// The heap as a `std.mem.Allocator`, for Zig `std` containers in user code.
pub const allocator = heap.allocator;