VMIO trait implementation for other components

[hiroki-chen]

I'm starting to provide the verified APIs (to some extent, specs) for components that utilize VMIOs for reading/writing. This should be the issue for tracking the progress.

[hiroki-chen]

The first experimental target is ostd::mm::dma. Seems that the current rwarc can be directly imported.

[hiroki-chen]

There's lifetime issue when designing reading/writing for DmaStream as they require VmIoOwner with explicit lifetime markers to prevent data races (so that we cannot transfer them across threads). However, DmaStream is a thin wrapper around an atomic reference counter so you basically clone it everywhere.

As a result, the introduction of the lifetime should be instead put in the impl block. I'm not sure if this is the best choice.

[hiroki-chen]

The lifetime marker is meaningless at runtime so verification would block the use of RwArc and will contaminate the struct. Perhaps we need to use the resource-based reasoning.

[hiroki-chen]

#390 Partially fulfills dma, let's see what can be further implemented.