From 3e37f599339bd05bc7097855747d4e80c6513863 Mon Sep 17 00:00:00 2001
From: Sebastien Boeuf <sebastien.boeuf@intel.com>
Date: Fri, 18 Oct 2019 15:04:44 -0700
Subject: [PATCH] pci: Add new DeviceRelocation trait

This new trait will allow the VMM to implement the mechanism following a
BAR modification regarding its location in the guest address space.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
---
 pci/src/device.rs | 15 +++++++++++++++
 pci/src/lib.rs    |  2 +-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/pci/src/device.rs b/pci/src/device.rs
index 1baeb0edd..47041fe42 100755
--- a/pci/src/device.rs
+++ b/pci/src/device.rs
@@ -91,3 +91,18 @@ pub trait PciDevice: BusDevice {
     /// * `data` - The data to write.
     fn write_bar(&mut self, _base: u64, _offset: u64, _data: &[u8]) {}
 }
+
+/// This trait defines a set of functions which can be triggered whenever a
+/// PCI device is modified in any way.
+pub trait DeviceRelocation: Send + Sync {
+    /// The BAR needs to be moved to a different location in the guest address
+    /// space. This follows a decision from the software running in the guest.
+    fn move_bar(
+        &self,
+        old_base: u64,
+        new_base: u64,
+        len: u64,
+        pci_dev: &mut dyn PciDevice,
+        region_type: PciBarRegionType,
+    );
+}
diff --git a/pci/src/lib.rs b/pci/src/lib.rs
index 400e4692e..4432bb3f1 100644
--- a/pci/src/lib.rs
+++ b/pci/src/lib.rs
@@ -23,7 +23,7 @@ pub use self::configuration::{
     PciNetworkControllerSubclass, PciProgrammingInterface, PciSerialBusSubClass, PciSubclass,
 };
 pub use self::device::{
-    Error as PciDeviceError, InterruptDelivery, InterruptParameters, PciDevice,
+    DeviceRelocation, Error as PciDeviceError, InterruptDelivery, InterruptParameters, PciDevice,
 };
 pub use self::msi::MsiCap;
 pub use self::msix::{MsixCap, MsixConfig, MsixTableEntry, MSIX_TABLE_ENTRY_SIZE};