Method new

devices/src/ioapic.rs:191–250

(
        id: String,
        apic_address: GuestAddress,
        interrupt_manager: &dyn InterruptManager<GroupConfig = MsiIrqGroupConfig>,
        state: Option<&IoapicState>,
    )

impl Ioapic {
    pub fn new(
        id: String,
        apic_address: GuestAddress,
        interrupt_manager: &dyn InterruptManager<GroupConfig = MsiIrqGroupConfig>,
        state: Option<&IoapicState>,
    ) -> Result<Ioapic> {
        let interrupt_source_group = interrupt_manager
            .create_group(MsiIrqGroupConfig {
                base: 0,
                count: NUM_IOAPIC_PINS as InterruptIndex,
            })
            .map_err(Error::CreateInterruptSourceGroup)?;

        let (id_reg, reg_sel, reg_entries, used_entries, apic_address) = if let Some(state) = &state
        {
            (
                state.id_reg,
                state.reg_sel,
                state.reg_entries,
                state.used_entries,
                GuestAddress(state.apic_address),
            )
        } else {
            (
                0,
                0,
                [0x10000; NUM_IOAPIC_PINS],
                [false; NUM_IOAPIC_PINS],
                apic_address,
            )
        };

        // The IOAPIC is created with entries already masked. The guest will be
        // in charge of unmasking them if/when necessary.
        let ioapic = Ioapic {
            id,
            id_reg,
            reg_sel,
            reg_entries,
            used_entries,
            apic_address,
            interrupt_source_group,
        };

        // When restoring the Ioapic, we must enable used entries.
        if state.is_some() {
            for (irq, entry) in ioapic.used_entries.iter().enumerate() {
                if *entry {
                    ioapic.update_entry(irq, false)?;
                }
            }

            ioapic
                .interrupt_source_group
                .set_gsi()
                .map_err(Error::UpdateInterrupt)?;
        }