aarch64: Introduce struct PciSpaceInfo for FDT

Currently, a tuple containing PCI space start address and PCI space
size is used to pass the PCI space information to the FDT creator.
In order to support the multiple PCI segment for FDT, more information
such as the PCI segment ID should be passed to the FDT creator. If we
still use a tuple to store these information, the code flexibility and
readablity will be harmed.

To address this issue, this commit replaces the tuple containing the
PCI space information to a structure `PciSpaceInfo` and uses a vector
of `PciSpaceInfo` to store PCI space information for each segment, so
that multiple PCI segment information can be passed to the FDT together.

Note that the scope of this commit will only contain the refactor of
original code, the actual multiple PCI segments support will be in
following series, and for now `--platform num_pci_segments` should only
be 1.

Signed-off-by: Henry Wang <Henry.Wang@arm.com>

vmm/src/device_manager.rs

@@ -3407,7 +3407,7 @@ impl DeviceManager {
         Arc::clone(self.pci_segments[0].pci_config_io.as_ref().unwrap())
     }
 
-    #[cfg(feature = "acpi")]
+    #[cfg(any(target_arch = "aarch64", feature = "acpi"))]
     pub(crate) fn pci_segments(&self) -> &Vec<PciSegment> {
         &self.pci_segments
     }

vmm/src/vm.rs

@@ -38,6 +38,8 @@ use arch::x86_64::tdx::TdVmmDataRegionType;
 #[cfg(feature = "tdx")]
 use arch::x86_64::tdx::{TdVmmDataRegion, TdvfSection};
 use arch::EntryPoint;
+#[cfg(target_arch = "aarch64")]
+use arch::PciSpaceInfo;
 #[cfg(any(target_arch = "aarch64", feature = "acpi"))]
 use arch::{NumaNode, NumaNodes};
 use devices::AcpiNotificationFlags;
@@ -72,7 +74,9 @@ use std::{result, str, thread};
 use vm_device::Bus;
 #[cfg(target_arch = "x86_64")]
 use vm_device::BusDevice;
-use vm_memory::{Address, Bytes, GuestAddress, GuestAddressSpace, GuestMemoryAtomic};
+#[cfg(target_arch = "x86_64")]
+use vm_memory::Address;
+use vm_memory::{Bytes, GuestAddress, GuestAddressSpace, GuestMemoryAtomic};
 #[cfg(feature = "tdx")]
 use vm_memory::{GuestMemory, GuestMemoryRegion};
 use vm_migration::{
@@ -1109,6 +1113,7 @@ impl Vm {
         let vcpu_mpidrs = self.cpu_manager.lock().unwrap().get_mpidrs();
         let vcpu_topology = self.cpu_manager.lock().unwrap().get_vcpu_topology();
         let mem = self.memory_manager.lock().unwrap().boot_guest_memory();
+        let mut pci_space_info: Vec<PciSpaceInfo> = Vec::new();
         let initramfs_config = match self.initramfs {
             Some(_) => Some(self.load_initramfs(&mem)?),
             None => None,
@@ -1121,26 +1126,17 @@ impl Vm {
             .get_device_info()
             .clone();
 
-        let pci_space_start: GuestAddress = self
-            .memory_manager
-            .lock()
-            .as_ref()
-            .unwrap()
-            .start_of_device_area();
-
-        let pci_space_end: GuestAddress = self
-            .memory_manager
-            .lock()
-            .as_ref()
-            .unwrap()
-            .end_of_device_area();
-
-        let pci_space_size = pci_space_end
-            .checked_offset_from(pci_space_start)
-            .ok_or(Error::MemOverflow)?
-            + 1;
-
-        let pci_space = (pci_space_start.0, pci_space_size);
+        for pci_segment in self.device_manager.lock().unwrap().pci_segments().iter() {
+            let pci_space = PciSpaceInfo {
+                pci_segment_id: pci_segment.id,
+                mmio_config_address: pci_segment.mmio_config_address,
+                pci_device_space_start: pci_segment.start_of_device_area,
+                pci_device_space_size: pci_segment.end_of_device_area
+                    - pci_segment.start_of_device_area
+                    + 1,
+            };
+            pci_space_info.push(pci_space);
+        }
 
         let virtio_iommu_bdf = self
             .device_manager
@@ -1165,7 +1161,7 @@ impl Vm {
             vcpu_topology,
             device_info,
             &initramfs_config,
-            &pci_space,
+            &pci_space_info,
             virtio_iommu_bdf.map(|bdf| bdf.into()),
             &*gic_device,
             &self.numa_nodes,
@@ -2765,7 +2761,7 @@ mod tests {
             &dev_info,
             &*gic,
             &None,
-            &(0x1_0000_0000, 0x1_0000),
+            &Vec::new(),
             &BTreeMap::new(),
             None,
         )