vm-memory

A library to access virtual machine's physical memory.

For a typical hypervisor, there are seveval components, such as boot loader, virtual device drivers, virtio backend drivers and vhost drivers etc, need to access VM's physical memory. The vm-memory crate provides a set of traits to decouple VM memory consumers from VM memory providers. Based on these traits, VM memory consumers could access VM's physical memory without knowing the implementation details of the VM memory provider. Thus hypervisor components based on these traits could be shared and reused by multiple hypervisors.

Platform Support

• Arch: x86, AMD64, ARM64
• OS: Linux/Unix/Windows

Usage

First, add the following to your Cargo.toml:

vm-memory = "0.1"

Next, add this to your crate root:

extern crate vm_memory;

Example

• Create VM physical memory objects in hypervisor specific ways. Use the default GuestMemoryMmap as an example:

    fn provide_mem_to_virt_dev() {
        let gm = GuestMemoryMmap::new(&[(GuestAddress(0), 0x1000), (GuestAddress(0x1000), 0x1000)]).unwrap();
        virt_device_io(&gm);
    }

• Consumers access VM's physical memory

    fn virt_device_io<T: GuestMemory>(mem: &T) {
        let sample_buf = &[1, 2, 3, 4, 5];
        assert_eq!(mem.write(sample_buf, GuestAddress(0xffc)).unwrap(), 5);
        let buf = &mut [0u8; 5];
        assert_eq!(mem.read(buf, GuestAddress(0xffc)).unwrap(), 5);
        assert_eq!(buf, sample_buf);
    }

Documentations & References

• Design of The vm-memory Crate
• TODO List
• The rust-vmm Project

License

This project is licensed under

• Apache License, Version 2.0, (LICENSE or http://www.apache.org/licenses/LICENSE-2.0)