VMM library (libsel4vmmplatsupport)

A library containing various VMM utilities and drivers that can be used to construct a Guest VM on a supported platform. This library makes use of ‘libsel4vm’ to implement VMM support. The main reference implementations using this library are the CAmkES VMs on Arm and IA32. The sources are available on GitHub.

Main features

The library contains Virtio support and Virtio drivers for PCI, Console, and Net. It provides a cross-VM connection/communication driver, guest image loading utilities (e.g. kernel, initramfs), libsel4vm memory helpers and utilities, and an IOPorts management interface.

On Arm, it further provides a VCPU fault handler module with HSR/Exception & SMC decoding and dispatching, PSCI handlers through a VCPU fault (+SMC handler) interface, guest reboot utilities, and guest OS boot interfaces for Linux VMs. It defines generic virtual device interfaces for generic access controlled devices (read/write privileges), and for generic forwarding devices via dispatching faults to external handlers. It also provides a virtual USB driver.

On IA32, the library supports ACPI table generation, PCI device passthrough helpers, and guest OS Boot interfaces for Linux VMs that provide boot VCPU initialisation, BIOS boot info structure generation, E820 map generation, and VESA initialisation.

API documentation

See below for usage documentation on libsel4vmmplatsupport interfaces.

Common Interfaces

• sel4vmmplatsupport/device.h: Provides a series of datastructures and helpers to manage VMM devices.
• sel4vmmplatsupport/device_utils.h: Provides various helpers to establish different types devices for a given VM instance
• sel4vmmplatsupport/guest_image.h: Provides general utilites to load guest vm images (e.g. kernel, initrd, modules)
• sel4vmmplatsupport/guest_memory_util.h: Provides various utilities and helpers for using the libsel4vm guest memory interface
• sel4vmmplatsupport/guest_vcpu_util.h: Provides abstractions and helpers for managing libsel4vm vcpus
• sel4vmmplatsupport/ioports.h: Useful abstraction for initialising, registering and handling ioport events for a guest VM instance
• sel4vmmplatsupport/drivers/cross_vm_connection.h: Facilitates the creation of communication channels between VM’s and other components on an seL4-based system
• sel4vmmplatsupport/drivers/pci.h: Interface presents a VMM PCI Driver, which manages the host’s PCI devices, and handles guest OS PCI config space read & writes
• sel4vmmplatsupport/drivers/pci_helper.h: This interface presents a series of helpers when using the VMM PCI Driver
• sel4vmmplatsupport/drivers/virtio_con.h: This interface provides the ability to initalise a VMM virtio console driver
• sel4vmmplatsupport/drivers/virtio_net.h: This interface provides the ability to initalise a VMM virtio net driver

Architecture Specific Interfaces

Arm

• sel4vmmplatsupport/arch/generic_forward_device.h: This interface facilitates the creation of a virtual device used for dispatching faults to external handlers
• sel4vmmplatsupport/arch/guest_boot_init.h: Provides helpers to initialise the booting state of a VM instance
• sel4vmmplatsupport/arch/guest_reboot,h: Provides a series of helpers for registering callbacks when rebooting the VMM
• sel4vmmplatsupport/arch/guest_vcpu_fault.h: Provides a module for registering and processing ARM vcpu faults
• sel4vmmplatsupport/arch/guest_vcpu_util.h: Provides abstractions and helpers for managing libsel4vm vcpus on an ARM platform
• sel4vmmplatsupport/arch/vpci.h: Presents a Virtual PCI driver for ARM-based VM’s
• sel4vmmplatsupport/arch/vusb.h: Presents a Virtual USB driver for ARM-based VM’s
• sel4vmmplatsupport/arch/ac_device.h: Facilitates the creation of generic virtual devices in a VM instance with access control permissions over the devices addressable memory

x86

• sel4vmmplatsupport/arch/acpi.h: Provides support for generating ACPI table in a guest x86 VM
• sel4vmmplatsupport/arch/guest_boot_init.h: Provides helpers to initialise the booting state of a VM instance
• sel4vmmplatsupport/arch/drivers/vmm_pci_helper.h: Interface presents a series of helpers for establishing VMM PCI support on x86 platforms