Trait vmcore::device_state::ChangeDeviceState

pub trait ChangeDeviceState {
    // Required methods
    fn start(&mut self);
    fn stop(&mut self) -> impl Send + Future<Output = ()>;
    fn reset(&mut self) -> impl Send + Future<Output = ()>;
}

Trait for transitioning device state.

Required Methods

fn start(&mut self)

Starts a device, allowing it to interact with the guest asynchronously.

For example, a device might process work queues that reside in guest memory on a separate thread.

Callers must ensure that the device is in a stopped state before calling this method.

This is a synchronous method instead of an asynchronous one because it is a notification only–callers do not need to wait for the device to finish starting to consider the VM started. Devices should kick off any tasks that need to run any return, without waiting.

fn stop(&mut self) -> impl Send + Future<Output = ()>

Stops a device’s asynchronous work.

After this returns, the device must not process any additional work. It should be in a stable state where it can be saved without losing data (if it implements the appropriate trait).

Callers must ensure that the device is in a started state before calling this method.

fn reset(&mut self) -> impl Send + Future<Output = ()>

Resets the device state to its initial state, for a fresh boot.

Callers must ensure that the device is in a stopped state before calling this method.

Object Safety

This trait is not object safe.

Implementors