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https://github.com/cloud-hypervisor/cloud-hypervisor.git
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vmm: device_manager: Use DeviceTree to store PCI devices
Extend and use the existing DeviceTree to retrieve useful information related to PCI devices. This removes the duplication with pci_devices field which was internal to the DeviceManager. Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit is contained in:
parent
c8c3cad8cb
commit
b06fd80fa9
@ -70,7 +70,7 @@ use pci::{
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DeviceRelocation, PciBarRegionType, PciBus, PciConfigIo, PciConfigMmio, PciDevice, PciRoot,
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};
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use seccomp::SeccompAction;
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use std::collections::{BTreeMap, HashMap};
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use std::collections::HashMap;
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use std::convert::TryInto;
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use std::fs::{read_link, File, OpenOptions};
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use std::io::{self, sink, stdout, Seek, SeekFrom};
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@ -825,7 +825,8 @@ impl PtyPair {
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}
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}
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enum PciDeviceHandle {
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#[derive(Clone)]
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pub enum PciDeviceHandle {
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#[cfg(feature = "kvm")]
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Vfio(Arc<Mutex<VfioPciDevice>>),
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Virtio(Arc<Mutex<VirtioPciDevice>>),
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@ -900,9 +901,6 @@ pub struct DeviceManager {
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// Bitmap of PCI devices to hotunplug.
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pci_devices_down: u32,
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// BTreeMap of PCI b/d/f to their corresponding MetaPciDevice.
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pci_devices: BTreeMap<u32, (String, PciDeviceHandle)>,
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// List of allocated IRQs for each PCI slot.
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pci_irq_slots: [u8; 32],
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@ -1007,7 +1005,6 @@ impl DeviceManager {
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iommu_device: None,
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pci_devices_up: 0,
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pci_devices_down: 0,
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pci_devices: BTreeMap::new(),
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pci_irq_slots: [0; 32],
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device_tree,
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#[cfg(feature = "acpi")]
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@ -2911,10 +2908,12 @@ impl DeviceManager {
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pci,
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vfio_pci_device.clone(),
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vfio_pci_device.clone(),
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PciDeviceHandle::Vfio(vfio_pci_device),
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pci_device_bdf,
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vfio_name.clone(),
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)?;
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node.pci_bdf = Some(pci_device_bdf);
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node.pci_device_handle = Some(PciDeviceHandle::Vfio(vfio_pci_device));
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self.device_tree
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.lock()
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.unwrap()
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@ -2928,9 +2927,7 @@ impl DeviceManager {
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pci_bus: &mut PciBus,
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bus_device: Arc<Mutex<dyn BusDevice>>,
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pci_device: Arc<Mutex<dyn PciDevice>>,
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pci_device_handle: PciDeviceHandle,
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bdf: u32,
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device_id: String,
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) -> DeviceManagerResult<Vec<(GuestAddress, GuestUsize, PciBarRegionType)>> {
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let bars = pci_device
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.lock()
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@ -2942,7 +2939,6 @@ impl DeviceManager {
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.add_device(bdf, pci_device)
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.map_err(DeviceManagerError::AddPciDevice)?;
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self.pci_devices.insert(bdf, (device_id, pci_device_handle));
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self.bus_devices.push(Arc::clone(&bus_device));
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pci_bus
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@ -3099,9 +3095,7 @@ impl DeviceManager {
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pci,
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virtio_pci_device.clone(),
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virtio_pci_device.clone(),
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PciDeviceHandle::Virtio(Arc::clone(&virtio_pci_device)),
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pci_device_bdf,
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virtio_device_id,
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)?;
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let bar_addr = virtio_pci_device.lock().unwrap().config_bar_addr();
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@ -3122,6 +3116,7 @@ impl DeviceManager {
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}
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node.migratable = Some(Arc::clone(&virtio_pci_device) as Arc<Mutex<dyn Migratable>>);
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node.pci_bdf = Some(pci_device_bdf);
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node.pci_device_handle = Some(PciDeviceHandle::Virtio(virtio_pci_device));
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self.device_tree.lock().unwrap().insert(id, node);
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Ok(pci_device_bdf)
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@ -3167,17 +3162,24 @@ impl DeviceManager {
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// Take care of updating the memory for VFIO PCI devices.
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#[cfg(feature = "kvm")]
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for (_, (_, pci_device_handle)) in self.pci_devices.iter() {
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if let PciDeviceHandle::Vfio(vfio_pci_device) = pci_device_handle {
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vfio_pci_device
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.lock()
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.unwrap()
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.dma_map(
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new_region.start_addr().raw_value(),
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new_region.len() as u64,
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new_region.as_ptr() as u64,
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)
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.map_err(DeviceManagerError::UpdateMemoryForVfioPciDevice)?;
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{
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let device_tree = self.device_tree.lock().unwrap();
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for pci_device_node in device_tree.pci_devices() {
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if let PciDeviceHandle::Vfio(vfio_pci_device) = pci_device_node
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.pci_device_handle
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.as_ref()
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.ok_or(DeviceManagerError::MissingPciDevice)?
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{
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vfio_pci_device
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.lock()
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.unwrap()
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.dma_map(
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new_region.start_addr().raw_value(),
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new_region.len() as u64,
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new_region.as_ptr() as u64,
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)
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.map_err(DeviceManagerError::UpdateMemoryForVfioPciDevice)?;
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}
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}
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}
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@ -3186,9 +3188,14 @@ impl DeviceManager {
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pub fn activate_virtio_devices(&self) -> DeviceManagerResult<()> {
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// Find virtio pci devices and activate any pending ones
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for (_, (_, pci_device_handle)) in self.pci_devices.iter() {
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let device_tree = self.device_tree.lock().unwrap();
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for pci_device_node in device_tree.pci_devices() {
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#[allow(irrefutable_let_patterns)]
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if let PciDeviceHandle::Virtio(virtio_pci_device) = pci_device_handle {
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if let PciDeviceHandle::Virtio(virtio_pci_device) = &pci_device_node
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.pci_device_handle
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.as_ref()
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.ok_or(DeviceManagerError::MissingPciDevice)?
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{
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virtio_pci_device.lock().unwrap().maybe_activate();
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}
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}
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@ -3246,45 +3253,59 @@ impl DeviceManager {
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}
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pub fn remove_device(&mut self, id: String) -> DeviceManagerResult<()> {
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for (pci_device_bdf, (device_id, pci_device_handle)) in self.pci_devices.iter() {
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if *device_id == id {
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#[allow(irrefutable_let_patterns)]
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if let PciDeviceHandle::Virtio(virtio_pci_device) = pci_device_handle {
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let device_type = VirtioDeviceType::from(
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virtio_pci_device
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.lock()
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.unwrap()
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.virtio_device()
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.lock()
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.unwrap()
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.device_type(),
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);
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match device_type {
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VirtioDeviceType::TYPE_NET
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| VirtioDeviceType::TYPE_BLOCK
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| VirtioDeviceType::TYPE_PMEM
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| VirtioDeviceType::TYPE_FS
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| VirtioDeviceType::TYPE_VSOCK => {}
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_ => return Err(DeviceManagerError::RemovalNotAllowed(device_type)),
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}
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}
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// The node can be directly a PCI node in case the 'id' refers to a
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// VFIO device or a virtio-pci one.
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// In case the 'id' refers to a virtio device, we must find the PCI
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// node by looking at the parent.
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let device_tree = self.device_tree.lock().unwrap();
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let node = device_tree
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.get(&id)
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.ok_or(DeviceManagerError::UnknownDeviceId(id))?;
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// Update the PCID bitmap
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self.pci_devices_down |= 1 << (*pci_device_bdf >> 3);
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let pci_device_node = if node.pci_bdf.is_some() && node.pci_device_handle.is_some() {
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node
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} else {
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let parent = node
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.parent
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.as_ref()
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.ok_or(DeviceManagerError::MissingNode)?;
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device_tree
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.get(parent)
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.ok_or(DeviceManagerError::MissingNode)?
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};
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// Remove the device from the device tree along with its parent.
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let mut device_tree = self.device_tree.lock().unwrap();
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if let Some(node) = device_tree.remove(&id) {
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if let Some(parent) = &node.parent {
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device_tree.remove(parent);
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}
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}
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return Ok(());
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let pci_device_bdf = pci_device_node
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.pci_bdf
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.ok_or(DeviceManagerError::MissingPciDevice)?;
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let pci_device_handle = pci_device_node
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.pci_device_handle
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.as_ref()
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.ok_or(DeviceManagerError::MissingPciDevice)?;
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#[allow(irrefutable_let_patterns)]
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if let PciDeviceHandle::Virtio(virtio_pci_device) = pci_device_handle {
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let device_type = VirtioDeviceType::from(
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virtio_pci_device
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.lock()
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.unwrap()
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.virtio_device()
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.lock()
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.unwrap()
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.device_type(),
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);
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match device_type {
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VirtioDeviceType::TYPE_NET
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| VirtioDeviceType::TYPE_BLOCK
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| VirtioDeviceType::TYPE_PMEM
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| VirtioDeviceType::TYPE_FS
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| VirtioDeviceType::TYPE_VSOCK => {}
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_ => return Err(DeviceManagerError::RemovalNotAllowed(device_type)),
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}
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}
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Err(DeviceManagerError::UnknownDeviceId(id))
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// Update the PCID bitmap
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self.pci_devices_down |= 1 << (pci_device_bdf >> 3);
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Ok(())
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}
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pub fn eject_device(&mut self, device_id: u8) -> DeviceManagerResult<()> {
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@ -3304,121 +3325,126 @@ impl DeviceManager {
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.put_device_id(device_id as usize)
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.map_err(DeviceManagerError::PutPciDeviceId)?;
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if let Some((_, pci_device_handle)) = self.pci_devices.remove(&pci_device_bdf) {
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let (pci_device, bus_device, virtio_device) = match pci_device_handle {
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#[cfg(feature = "kvm")]
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PciDeviceHandle::Vfio(vfio_pci_device) => {
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{
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// Unregister DMA mapping in IOMMU.
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// Do not unregister the virtio-mem region, as it is
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// directly handled by the virtio-mem device.
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let dev = vfio_pci_device.lock().unwrap();
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for (_, zone) in self.memory_manager.lock().unwrap().memory_zones().iter() {
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for region in zone.regions() {
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dev.dma_unmap(region.start_addr().raw_value(), region.len() as u64)
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.map_err(DeviceManagerError::VfioDmaUnmap)?;
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}
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}
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// Remove the device from the device tree along with its children.
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let mut device_tree = self.device_tree.lock().unwrap();
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let pci_device_node = device_tree
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.remove_node_by_pci_bdf(pci_device_bdf)
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.ok_or(DeviceManagerError::MissingPciDevice)?;
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for child in pci_device_node.children.iter() {
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device_tree.remove(child);
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}
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// Unregister the VFIO mapping handler from all virtio-mem
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// devices.
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if !dev.iommu_attached() {
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for virtio_mem_device in self.virtio_mem_devices.iter() {
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virtio_mem_device
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.lock()
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.unwrap()
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.remove_dma_mapping_handler(pci_device_bdf)
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.map_err(
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DeviceManagerError::RemoveDmaMappingHandlerVirtioMem,
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)?;
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}
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let pci_device_handle = pci_device_node
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.pci_device_handle
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.ok_or(DeviceManagerError::MissingPciDevice)?;
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let (pci_device, bus_device, virtio_device) = match pci_device_handle {
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#[cfg(feature = "kvm")]
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PciDeviceHandle::Vfio(vfio_pci_device) => {
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{
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// Unregister DMA mapping in IOMMU.
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// Do not unregister the virtio-mem region, as it is
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// directly handled by the virtio-mem device.
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let dev = vfio_pci_device.lock().unwrap();
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for (_, zone) in self.memory_manager.lock().unwrap().memory_zones().iter() {
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for region in zone.regions() {
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dev.dma_unmap(region.start_addr().raw_value(), region.len() as u64)
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.map_err(DeviceManagerError::VfioDmaUnmap)?;
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}
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}
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(
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Arc::clone(&vfio_pci_device) as Arc<Mutex<dyn PciDevice>>,
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Arc::clone(&vfio_pci_device) as Arc<Mutex<dyn BusDevice>>,
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None as Option<VirtioDeviceArc>,
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)
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}
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PciDeviceHandle::Virtio(virtio_pci_device) => {
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let bar_addr = virtio_pci_device.lock().unwrap().config_bar_addr();
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for (event, addr) in virtio_pci_device.lock().unwrap().ioeventfds(bar_addr) {
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let io_addr = IoEventAddress::Mmio(addr);
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self.address_manager
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.vm
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.unregister_ioevent(event, &io_addr)
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.map_err(|e| DeviceManagerError::UnRegisterIoevent(e.into()))?;
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// Unregister the VFIO mapping handler from all virtio-mem
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// devices.
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if !dev.iommu_attached() {
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for virtio_mem_device in self.virtio_mem_devices.iter() {
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virtio_mem_device
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.lock()
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.unwrap()
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.remove_dma_mapping_handler(pci_device_bdf)
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.map_err(DeviceManagerError::RemoveDmaMappingHandlerVirtioMem)?;
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}
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}
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}
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(
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Arc::clone(&virtio_pci_device) as Arc<Mutex<dyn PciDevice>>,
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Arc::clone(&virtio_pci_device) as Arc<Mutex<dyn BusDevice>>,
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Some(virtio_pci_device.lock().unwrap().virtio_device()),
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(
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Arc::clone(&vfio_pci_device) as Arc<Mutex<dyn PciDevice>>,
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Arc::clone(&vfio_pci_device) as Arc<Mutex<dyn BusDevice>>,
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None as Option<VirtioDeviceArc>,
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)
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}
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PciDeviceHandle::Virtio(virtio_pci_device) => {
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let bar_addr = virtio_pci_device.lock().unwrap().config_bar_addr();
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for (event, addr) in virtio_pci_device.lock().unwrap().ioeventfds(bar_addr) {
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let io_addr = IoEventAddress::Mmio(addr);
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self.address_manager
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.vm
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.unregister_ioevent(event, &io_addr)
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.map_err(|e| DeviceManagerError::UnRegisterIoevent(e.into()))?;
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}
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(
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Arc::clone(&virtio_pci_device) as Arc<Mutex<dyn PciDevice>>,
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Arc::clone(&virtio_pci_device) as Arc<Mutex<dyn BusDevice>>,
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Some(virtio_pci_device.lock().unwrap().virtio_device()),
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)
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}
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};
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// Free the allocated BARs
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pci_device
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.lock()
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.unwrap()
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.free_bars(&mut self.address_manager.allocator.lock().unwrap())
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.map_err(DeviceManagerError::FreePciBars)?;
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// Remove the device from the PCI bus
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pci.lock()
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.unwrap()
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.remove_by_device(&pci_device)
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.map_err(DeviceManagerError::RemoveDeviceFromPciBus)?;
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#[cfg(target_arch = "x86_64")]
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// Remove the device from the IO bus
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self.io_bus()
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.remove_by_device(&bus_device)
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.map_err(DeviceManagerError::RemoveDeviceFromIoBus)?;
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// Remove the device from the MMIO bus
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self.mmio_bus()
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.remove_by_device(&bus_device)
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.map_err(DeviceManagerError::RemoveDeviceFromMmioBus)?;
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// Remove the device from the list of BusDevice held by the
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// DeviceManager.
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self.bus_devices
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.retain(|dev| !Arc::ptr_eq(dev, &bus_device));
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// Shutdown and remove the underlying virtio-device if present
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if let Some(virtio_device) = virtio_device {
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for mapping in virtio_device.lock().unwrap().userspace_mappings() {
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self.memory_manager
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.lock()
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.unwrap()
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.remove_userspace_mapping(
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mapping.addr.raw_value(),
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mapping.len,
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mapping.host_addr,
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mapping.mergeable,
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mapping.mem_slot,
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)
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}
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};
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// Free the allocated BARs
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pci_device
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.lock()
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.unwrap()
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.free_bars(&mut self.address_manager.allocator.lock().unwrap())
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.map_err(DeviceManagerError::FreePciBars)?;
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// Remove the device from the PCI bus
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pci.lock()
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.unwrap()
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.remove_by_device(&pci_device)
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.map_err(DeviceManagerError::RemoveDeviceFromPciBus)?;
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#[cfg(target_arch = "x86_64")]
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// Remove the device from the IO bus
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self.io_bus()
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.remove_by_device(&bus_device)
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.map_err(DeviceManagerError::RemoveDeviceFromIoBus)?;
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// Remove the device from the MMIO bus
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self.mmio_bus()
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.remove_by_device(&bus_device)
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.map_err(DeviceManagerError::RemoveDeviceFromMmioBus)?;
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// Remove the device from the list of BusDevice held by the
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// DeviceManager.
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self.bus_devices
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.retain(|dev| !Arc::ptr_eq(dev, &bus_device));
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// Shutdown and remove the underlying virtio-device if present
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if let Some(virtio_device) = virtio_device {
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for mapping in virtio_device.lock().unwrap().userspace_mappings() {
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self.memory_manager
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.lock()
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.unwrap()
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.remove_userspace_mapping(
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mapping.addr.raw_value(),
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mapping.len,
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mapping.host_addr,
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mapping.mergeable,
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mapping.mem_slot,
|
||||
)
|
||||
.map_err(DeviceManagerError::MemoryManager)?;
|
||||
}
|
||||
|
||||
virtio_device.lock().unwrap().shutdown();
|
||||
|
||||
self.virtio_devices
|
||||
.retain(|(d, _, _)| !Arc::ptr_eq(d, &virtio_device));
|
||||
.map_err(DeviceManagerError::MemoryManager)?;
|
||||
}
|
||||
|
||||
// At this point, the device has been removed from all the list and
|
||||
// buses where it was stored. At the end of this function, after
|
||||
// any_device, bus_device and pci_device are released, the actual
|
||||
// device will be dropped.
|
||||
virtio_device.lock().unwrap().shutdown();
|
||||
|
||||
Ok(())
|
||||
} else {
|
||||
Err(DeviceManagerError::MissingPciDevice)
|
||||
self.virtio_devices
|
||||
.retain(|(d, _, _)| !Arc::ptr_eq(d, &virtio_device));
|
||||
}
|
||||
|
||||
// At this point, the device has been removed from all the list and
|
||||
// buses where it was stored. At the end of this function, after
|
||||
// any_device, bus_device and pci_device are released, the actual
|
||||
// device will be dropped.
|
||||
Ok(())
|
||||
}
|
||||
|
||||
fn hotplug_virtio_pci_device(
|
||||
|
@ -2,6 +2,7 @@
|
||||
//
|
||||
// SPDX-License-Identifier: Apache-2.0
|
||||
|
||||
use crate::device_manager::PciDeviceHandle;
|
||||
use std::collections::HashMap;
|
||||
use std::sync::{Arc, Mutex};
|
||||
use vm_device::Resource;
|
||||
@ -16,6 +17,8 @@ pub struct DeviceNode {
|
||||
#[serde(skip)]
|
||||
pub migratable: Option<Arc<Mutex<dyn Migratable>>>,
|
||||
pub pci_bdf: Option<u32>,
|
||||
#[serde(skip)]
|
||||
pub pci_device_handle: Option<PciDeviceHandle>,
|
||||
}
|
||||
|
||||
impl DeviceNode {
|
||||
@ -27,6 +30,7 @@ impl DeviceNode {
|
||||
children: Vec::new(),
|
||||
migratable,
|
||||
pci_bdf: None,
|
||||
pci_device_handle: None,
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -72,6 +76,29 @@ impl DeviceTree {
|
||||
pub fn breadth_first_traversal(&self) -> BftIter {
|
||||
BftIter::new(&self.0)
|
||||
}
|
||||
pub fn pci_devices(&self) -> Vec<&DeviceNode> {
|
||||
self.0
|
||||
.values()
|
||||
.filter(|v| v.pci_bdf.is_some() && v.pci_device_handle.is_some())
|
||||
.collect()
|
||||
}
|
||||
pub fn remove_node_by_pci_bdf(&mut self, pci_bdf: u32) -> Option<DeviceNode> {
|
||||
let mut id = None;
|
||||
for (k, v) in self.0.iter() {
|
||||
if let Some(bdf) = v.pci_bdf {
|
||||
if bdf == pci_bdf {
|
||||
id = Some(k.clone());
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if let Some(id) = &id {
|
||||
self.0.remove(id)
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Breadth first traversal iterator.
|
||||
|
Loading…
x
Reference in New Issue
Block a user