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use super::*;
impl Vmm {
/// Handles an event from the event loop.
pub(super) fn handle_event(&self, event: crate::event::VmmEvent) {
use crate::event::VmmEvent;
match event {
VmmEvent::VcpuExit { vcpu_id, exit } => {
self.handle_vcpu_exit(vcpu_id, exit);
}
VmmEvent::DeviceIo {
device_id,
is_read,
addr,
data,
} => {
self.handle_device_io(device_id, is_read, addr, data);
}
VmmEvent::Timer { id } => {
tracing::trace!("Timer {} fired", id);
// Timer handling would go here (e.g., for RTC, PIT, etc.)
}
VmmEvent::Shutdown => {
tracing::info!("Shutdown requested");
self.running.store(false, Ordering::SeqCst);
}
}
}
/// Handles a vCPU exit event.
///
/// This processes exits from the hypervisor such as I/O, MMIO, and special
/// instructions that require VMM intervention.
fn handle_vcpu_exit(&self, vcpu_id: u32, exit: arcbox_hypervisor::VcpuExit) {
use arcbox_hypervisor::VcpuExit;
match &exit {
VcpuExit::Halt => {
tracing::debug!("vCPU {} halted", vcpu_id);
// HLT instruction - guest is idle, can reduce CPU usage
// In a real implementation, we might pause the vCPU until an interrupt
}
VcpuExit::IoOut { port, size, data } => {
tracing::trace!(
"vCPU {} I/O out: port={:#x}, size={}, data={:#x}",
vcpu_id,
port,
size,
data
);
self.handle_io_out(*port, *size, *data);
}
VcpuExit::IoIn { port, size } => {
tracing::trace!("vCPU {} I/O in: port={:#x}, size={}", vcpu_id, port, size);
let _value = self.handle_io_in(*port, *size);
// Note: The value would need to be written back to the vCPU,
// which requires access to the vCPU registers.
}
VcpuExit::MmioRead { addr, size } => {
tracing::trace!(
"vCPU {} MMIO read: addr={:#x}, size={}",
vcpu_id,
addr,
size
);
if let Some(ref device_manager) = self.device_manager {
match device_manager.handle_mmio_read(*addr, *size as usize) {
Ok(value) => {
tracing::trace!("MMIO read returned: {:#x}", value);
// Note: Value would need to be written back to vCPU
}
Err(e) => {
tracing::warn!("MMIO read failed at {:#x}: {}", addr, e);
}
}
}
}
VcpuExit::MmioWrite { addr, size, data } => {
tracing::trace!(
"vCPU {} MMIO write: addr={:#x}, size={}, data={:#x}",
vcpu_id,
addr,
size,
data
);
if let Some(ref device_manager) = self.device_manager {
if let Err(e) = device_manager.handle_mmio_write(*addr, *size as usize, *data) {
tracing::warn!("MMIO write failed at {:#x}: {}", addr, e);
}
}
}
VcpuExit::Hypercall { nr, args } => {
tracing::debug!("vCPU {} hypercall: nr={}, args={:?}", vcpu_id, nr, args);
// Hypercall handling - used for paravirtualization
self.handle_hypercall(vcpu_id, *nr, *args);
}
VcpuExit::SystemReset => {
tracing::info!("vCPU {} requested system reset", vcpu_id);
// Guest requested a reset - could restart VM or signal caller
self.running.store(false, Ordering::SeqCst);
}
VcpuExit::Shutdown => {
tracing::info!("vCPU {} requested shutdown", vcpu_id);
self.running.store(false, Ordering::SeqCst);
}
VcpuExit::Unknown(code) => {
tracing::warn!("vCPU {} unknown exit: {}", vcpu_id, code);
}
VcpuExit::Debug => {
tracing::debug!("vCPU {} unhandled exit: {:?}", vcpu_id, exit);
}
}
}
/// Handles device I/O events.
fn handle_device_io(&self, device_id: u32, is_read: bool, addr: u64, data: Option<u64>) {
if let Some(ref device_manager) = self.device_manager {
if is_read {
match device_manager.handle_mmio_read(addr, 4) {
Ok(value) => {
tracing::trace!("Device {} read at {:#x}: {:#x}", device_id, addr, value);
}
Err(e) => {
tracing::warn!("Device {} read failed: {}", device_id, e);
}
}
} else if let Some(value) = data {
if let Err(e) = device_manager.handle_mmio_write(addr, 4, value) {
tracing::warn!("Device {} write failed: {}", device_id, e);
}
}
}
}
/// Handles I/O port output.
fn handle_io_out(&self, port: u16, size: u8, data: u64) {
match port {
// Serial ports (COM1-COM4)
0x3F8..=0x3FF => {
// COM1 - primary serial port
if port == 0x3F8 {
// Data register - output character
let ch = (data & 0xFF) as u8;
if ch.is_ascii() && (ch.is_ascii_graphic() || ch.is_ascii_whitespace()) {
tracing::trace!("Serial output: '{}'", ch as char);
}
}
}
0x2F8..=0x2FF => {
// COM2
}
// Debug port (Bochs/QEMU convention)
0x402 => {
let ch = (data & 0xFF) as u8;
if ch.is_ascii() {
tracing::debug!("Debug port: '{}'", ch as char);
}
}
// ACPI power management
0x604 => {
// ACPI PM1a control - check for S5 (shutdown)
if data & 0x2000 != 0 {
tracing::info!("ACPI shutdown requested");
// Would signal shutdown here
}
}
// PIC (Programmable Interrupt Controller)
0x20 | 0x21 | 0xA0 | 0xA1 => {
tracing::trace!("PIC write: port={:#x}, data={:#x}", port, data);
}
// PIT (Programmable Interval Timer)
0x40..=0x43 => {
tracing::trace!("PIT write: port={:#x}, data={:#x}", port, data);
}
_ => {
tracing::trace!(
"Unhandled I/O out: port={:#x}, size={}, data={:#x}",
port,
size,
data
);
}
}
}
/// Handles I/O port input.
fn handle_io_in(&self, port: u16, size: u8) -> u64 {
match port {
// Serial ports - Line Status Register
0x3FD => {
// LSR: Always report transmitter empty (0x60)
0x60
}
// RTC (Real-Time Clock)
0x70 | 0x71 => 0,
// Keyboard controller status
0x64 => {
// Report output buffer empty, input buffer not full
0x00
}
// PIC
0x20 | 0x21 | 0xA0 | 0xA1 => 0xFF,
_ => {
tracing::trace!("Unhandled I/O in: port={:#x}, size={}", port, size);
0xFF // Return all 1s for unhandled ports
}
}
}
/// Handles a hypercall from the guest.
fn handle_hypercall(&self, vcpu_id: u32, nr: u64, args: [u64; 6]) {
// Common hypercall numbers (KVM convention):
// 0: KVM_HC_VAPIC_POLL_IRQ
// 1: KVM_HC_MMU_OP (deprecated)
// 2: KVM_HC_FEATURES
// 3: KVM_HC_PPC_MAP_MAGIC_PAGE
// 4: KVM_HC_KICK_CPU
// 5: KVM_HC_SEND_IPI
// 9: KVM_HC_MAP_GPA_RANGE
match nr {
0 => {
// Poll for pending interrupts
tracing::trace!("vCPU {} hypercall: VAPIC_POLL_IRQ", vcpu_id);
}
2 => {
// Get features
tracing::trace!("vCPU {} hypercall: GET_FEATURES", vcpu_id);
}
4 => {
// Kick another vCPU
let target_vcpu = args[0] as u32;
tracing::trace!(
"vCPU {} hypercall: KICK_CPU target={}",
vcpu_id,
target_vcpu
);
}
_ => {
tracing::debug!(
"vCPU {} unhandled hypercall: nr={}, args={:?}",
vcpu_id,
nr,
args
);
}
}
}
}