pci: remove unused members of the PciDevice trait

We are not really using the `as_any` and `id` members of the PciDevice
trait. At the moment, only VirtIO devices and the PCI root port is
implementing PciDevice and we are never iterating over the container of
PCI devices.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

src/pci/src/bus.rs

@@ -5,7 +5,6 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
-use std::any::Any;
 use std::collections::HashMap;
 use std::ops::DerefMut;
 use std::sync::{Arc, Barrier, Mutex};
@@ -87,14 +86,6 @@ impl PciDevice for PciRoot {
     fn read_config_register(&mut self, reg_idx: usize) -> u32 {
         self.config.read_reg(reg_idx)
     }
-
-    fn as_any_mut(&mut self) -> &mut dyn Any {
-        self
-    }
-
-    fn id(&self) -> Option<String> {
-        None
-    }
 }
 
 pub struct PciBus {

src/pci/src/device.rs

@@ -5,14 +5,12 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
-use std::any::Any;
 use std::sync::{Arc, Barrier};
 use std::{io, result};
 
 use vm_allocator::AddressAllocator;
 
 use crate::configuration::{self, PciBarRegionType};
-use crate::PciBarConfiguration;
 
 #[derive(Debug, thiserror::Error, displaydoc::Display)]
 pub enum Error {
@@ -42,8 +40,8 @@ pub trait PciDevice: Send {
         &mut self,
         _mmio32_allocator: &mut AddressAllocator,
         _mmio64_allocator: &mut AddressAllocator,
-    ) -> Result<Vec<PciBarConfiguration>> {
-        Ok(Vec::new())
+    ) -> Result<()> {
+        Ok(())
     }
 
     /// Frees the PCI BARs previously allocated with a call to allocate_bars().
@@ -89,12 +87,6 @@ pub trait PciDevice: Send {
     fn move_bar(&mut self, _old_base: u64, _new_base: u64) -> result::Result<(), io::Error> {
         Ok(())
     }
-    /// Provides a mutable reference to the Any trait. This is useful to let
-    /// the caller have access to the underlying type behind the trait.
-    fn as_any_mut(&mut self) -> &mut dyn Any;
-
-    /// Optionally returns a unique identifier.
-    fn id(&self) -> Option<String>;
 }
 
 /// This trait defines a set of functions which can be triggered whenever a

src/vmm/src/devices/virtio/transport/pci/device.rs

@@ -7,7 +7,6 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
-use std::any::Any;
 use std::cmp;
 use std::collections::HashMap;
 use std::fmt::{Debug, Formatter};
@@ -870,7 +869,7 @@ impl PciDevice for VirtioPciDevice {
         &mut self,
         mmio32_allocator: &mut AddressAllocator,
         mmio64_allocator: &mut AddressAllocator,
-    ) -> std::result::Result<Vec<PciBarConfiguration>, PciDeviceError> {
+    ) -> std::result::Result<(), PciDeviceError> {
         let device_clone = self.device.clone();
         let device = device_clone.lock().unwrap();
 
@@ -905,25 +904,6 @@ impl PciDevice for VirtioPciDevice {
         self.add_pci_capabilities()?;
         self.bar_region = bar;
 
-        Ok(vec![bar])
-    }
-
-    fn free_bars(
-        &mut self,
-        mmio32_allocator: &mut AddressAllocator,
-        mmio64_allocator: &mut AddressAllocator,
-    ) -> std::result::Result<(), PciDeviceError> {
-        assert_eq!(
-            self.bar_region.region_type,
-            PciBarRegionType::Memory64BitRegion
-        );
-
-        let range = RangeInclusive::new(
-            self.bar_region.addr,
-            self.bar_region.addr + self.bar_region.size,
-        )
-        .unwrap();
-        mmio64_allocator.free(&range);
         Ok(())
     }
 
@@ -1083,14 +1063,6 @@ impl PciDevice for VirtioPciDevice {
 
         None
     }
-
-    fn id(&self) -> Option<String> {
-        Some(self.id.clone())
-    }
-
-    fn as_any_mut(&mut self) -> &mut dyn Any {
-        self
-    }
 }
 
 impl BusDevice for VirtioPciDevice {