From 34d1f435f4bf5e40e96951470a0111c027e8a03d Mon Sep 17 00:00:00 2001
From: Sebastien Boeuf <sebastien.boeuf@intel.com>
Date: Wed, 11 Mar 2020 09:35:12 +0100
Subject: [PATCH] vfio: pci: Implement free_bars() from the PciDevice trait

In order to provide the tools for a complete cleanup whenever a VFIO PCI
device is removed from the VM, the VfioPciDevice implements free_bars()
method from PciDevice trait. This will take care of removing the IO and
MMIO ranges previously reserved through the vm-allocator.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
---
 vfio/src/vfio_pci.rs | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/vfio/src/vfio_pci.rs b/vfio/src/vfio_pci.rs
index 4ebe43ada..176ac0823 100644
--- a/vfio/src/vfio_pci.rs
+++ b/vfio/src/vfio_pci.rs
@@ -222,6 +222,7 @@ impl Interrupt {
 struct MmioRegion {
     start: GuestAddress,
     length: GuestUsize,
+    type_: PciBarRegionType,
     index: u32,
     mem_slot: Option<u32>,
     host_addr: Option<u64>,
@@ -799,6 +800,7 @@ impl PciDevice for VfioPciDevice {
             self.mmio_regions.push(MmioRegion {
                 start: bar_addr,
                 length: region_size,
+                type_: region_type,
                 index: bar_id as u32,
                 mem_slot: None,
                 host_addr: None,
@@ -818,6 +820,26 @@ impl PciDevice for VfioPciDevice {
         Ok(ranges)
     }
 
+    fn free_bars(
+        &mut self,
+        allocator: &mut SystemAllocator,
+    ) -> std::result::Result<(), PciDeviceError> {
+        for region in self.mmio_regions.iter() {
+            match region.type_ {
+                PciBarRegionType::IORegion => {
+                    allocator.free_io_addresses(region.start, region.length);
+                }
+                PciBarRegionType::Memory32BitRegion => {
+                    allocator.free_mmio_hole_addresses(region.start, region.length);
+                }
+                PciBarRegionType::Memory64BitRegion => {
+                    allocator.free_mmio_addresses(region.start, region.length);
+                }
+            }
+        }
+        Ok(())
+    }
+
     fn write_config_register(&mut self, reg_idx: usize, offset: u64, data: &[u8]) {
         // When the guest wants to write to a BAR, we trap it into
         // our local configuration space. We're not reprogramming