[VFIO] Chapter 2, Section 5: Wire it all up - #6219
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We already ensure that the Msix is present in the device. The `vfio_calculate_bar_areas` was one weird place that still was accepting it as an `Option` Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Add utility functions for DMA mapping guest memory to the device. This must be done only once on first device setup/teardown. PciMng will be handling this in the future commits. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Add functions for creation of KVM VFIO device and VFIO container. These will need to be created once on the first device init. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Add logic to the PciDevices to create new VFIO devices. As an additional step in VFIO device setup, guest RAM regions are mapped into the VFIO container's IOMMU so the device can DMA directly to guest memory. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Since `device-passthrough` API is now connected, we need to not set dummy values for it before starting the VM. Otherwise the VM startup will fail. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Current device passthrough implementation has some restrictions: - Does not work without PCI since VFIO devices are PCI devices - Does not work with virtio-mem device since we don't update DMA mappings on hot-plug/unplug - Does not work with virtio-balloon since it can `fadvise` on memory In order to prevent VMs being launched with invalid configurations, implement multiple checks for invalid configurations: - At API level, prevent adding of incompatible combinations (VFIO after balloon/mem or in reverse) - At VM creation or snapshot restoration since they get VmResources from other sources. Checks are a bit spread out. Most are in the `rpc_interface.rs` but there is one in the `device_manager.rs` as well. This is just an annoyance of dealing with `VmResources`. In the future we should delete `VmResources` and add devices directly to the `DeviceManager` which can implement all necessary compatibility checks. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
Passthrough device state is opaque to the VMM and cannot be serialized or restored. Add these devices to the list of snapshot-incompatible devices so that snapshot requests are rejected with a clear error instead of producing a corrupt snapshot. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
During runtime VFIO devices will use pread64/pwrite64 syscalls on Vcpu thread to interact with BARs. During teardown VFIO device is reset and vfio-ioctls does additional syscalls to clean it up. Signed-off-by: Egor Lazarchuk <yegorlz@amazon.co.uk>
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Changes
This PR finally wires all the parts of VFIO together and allows VM to boot with VFIO devices attached
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CONTRIBUTING.md.PR Checklist
tools/devtool checkbuild --allto verify that the PR passesbuild checks on all supported architectures.
tools/devtool checkstyle --no-clippyto verify that the PRpasses the automated style checks.
how they are solving the problem in a clear and encompassing way.
in the PR.
CHANGELOG.md.Runbook for Firecracker API changes.
integration tests.
TODO.rust-vmm.