devices: PCI: add capabilities callback

virtio devices should be able to specify capabilities

BUG=chromium:936567
TEST=boot vm

Change-Id: I049f9967eb59a7904528fff5aea844e30c636e28
Reviewed-on: https://chromium-review.googlesource.com/1493012
Commit-Ready: Daniel Prilik <prilik@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Stephen Barber <smbarber@chromium.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/devices/src/pci/pci_device.rs b/devices/src/pci/pci_device.rs
index d5bc741..bd811b5 100644
--- a/devices/src/pci/pci_device.rs
+++ b/devices/src/pci/pci_device.rs
@@ -76,6 +76,11 @@ pub trait PciDevice: Send {
         Ok(Vec::new())
     }
 
+    /// Register any capabilties specified by the device.
+    fn register_device_capabilities(&mut self) -> Result<()> {
+        Ok(())
+    }
+
     /// Gets a list of ioeventfds that should be registered with the running VM. The list is
     /// returned as a Vec of (eventfd, addr, datamatch) tuples.
     fn ioeventfds(&self) -> Vec<(&EventFd, u64, Datamatch)> {
@@ -160,6 +165,9 @@ impl<T: PciDevice + ?Sized> PciDevice for Box<T> {
     fn allocate_device_bars(&mut self, resources: &mut SystemAllocator) -> Result<Vec<(u64, u64)>> {
         (**self).allocate_device_bars(resources)
     }
+    fn register_device_capabilities(&mut self) -> Result<()> {
+        (**self).register_device_capabilities()
+    }
     fn ioeventfds(&self) -> Vec<(&EventFd, u64, Datamatch)> {
         (**self).ioeventfds()
     }