The payoff milestone: files are served by a user-space process, reached over
IPC — the kernel never sees a path or an fd.
- lib/vfs_proto.zig: the VFS wire protocol (Op, Request/Reply fixed header +
inline payload, Stat), shared by client and server; one message <= MSG_MAX.
- lib/ipc.zig: replyWait() — the server-side dual-return stub (length in rax,
badge in rdx via a "+{rdx}" read-write operand), deferred from M7.
- sbin/vfs.zig: the real VFS server — an in-heap ramfs (open creates a node)
with an IPC_ReplyWait dispatch loop serving open/read/write/stat/close.
Registers its endpoint under the well-known vfs id at startup.
- lib/unistd.zig: POSIX-style client API in rt — a per-process fd table +
open/close/read/write/lseek/stat, each an IPC_Call to the VFS. The kernel
knows nothing of fds; the table lives here.
- lib/stdio.zig: C stdio over unistd — FILE + fopen/fclose/fread/fwrite/
fseek/ftell/rewind/feof/ferror/fputs/fputc/fgetc (unbuffered for now).
- sbin/vfstest.zig: a client that opens/writes/seeks/reads a file and only
heartbeats "vfstest: ok" if the round trip matched. Packed in the initrd.
- New `vfs` test drives it end to end. initrd test relaxed to generic
liveness. Suite 31/31.
Ship more than one user binary: the bootloader now ferries an initrd bundle
(the VFS server + future drivers) alongside sbin/init, and the kernel unpacks
and spawns each program.
- src/user/proto/initrd.zig: the container format (Header{magic,count} +
Entry{name[32],offset,len} + blobs) with a validating Reader, shared by the
kernel and the packer.
- tools/mkinitrd.py: host-side packer (Python — trivial format, and sidesteps
the reworked Zig 0.16 std fs/args API). build.zig runs it on the built user
binaries via addSystemCommand and installs initrd.img to zig-out/bin + the
ESP root.
- BootInfo gains initrd_base/initrd_len; efi.zig loadInit refactored into a
shared loadFile, and loadInitrd ferries \initrd.img into surviving
LoaderData like init.
- main.zig startInitrdBinaries(): parse the image, spawn every entry (kernel-
spawns-all for now; init takes over via sys_spawn later).
- sbin/vfs.zig: a heartbeat stub (the real VFS server is M9), packed into the
initrd to prove the pipeline.
- New `initrd` test: parse + spawn + confirm the vfs stub reaches ring 3 and
heartbeats. Harness ships initrd.img on the ESP. Suite 30/30.
Daniel Samson