From 6566c739e1c1e2a68704a32db317059f9623ac89 Mon Sep 17 00:00:00 2001
From: Sebastien Boeuf <sebastien.boeuf@intel.com>
Date: Fri, 4 Oct 2019 10:47:13 -0700
Subject: [PATCH] vm-virtio: Add IOMMU support to virtio-vsock

Adding virtio feature VIRTIO_F_IOMMU_PLATFORM when explicitly asked by
the user. The need for this feature is to be able to attach the virtio
device to a virtual IOMMU.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
---
 vm-virtio/src/vsock/device.rs | 10 +++++++---
 vm-virtio/src/vsock/mod.rs    |  2 +-
 vmm/src/device_manager.rs     |  2 +-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/vm-virtio/src/vsock/device.rs b/vm-virtio/src/vsock/device.rs
index d0eb9fe9e..0609d7a23 100644
--- a/vm-virtio/src/vsock/device.rs
+++ b/vm-virtio/src/vsock/device.rs
@@ -41,7 +41,7 @@ use crate::Error as DeviceError;
 use crate::VirtioInterrupt;
 use crate::{
     ActivateError, ActivateResult, DeviceEventT, Queue, VirtioDevice, VirtioDeviceType,
-    VirtioInterruptType, VIRTIO_F_IN_ORDER, VIRTIO_F_VERSION_1,
+    VirtioInterruptType, VIRTIO_F_IN_ORDER, VIRTIO_F_IOMMU_PLATFORM, VIRTIO_F_VERSION_1,
 };
 use byteorder::{ByteOrder, LittleEndian};
 use vm_memory::GuestMemoryMmap;
@@ -366,8 +366,12 @@ where
 {
     /// Create a new virtio-vsock device with the given VM CID and vsock
     /// backend.
-    pub fn new(cid: u64, backend: B) -> io::Result<Vsock<B>> {
-        let avail_features = 1u64 << VIRTIO_F_VERSION_1 | 1u64 << VIRTIO_F_IN_ORDER;
+    pub fn new(cid: u64, backend: B, iommu: bool) -> io::Result<Vsock<B>> {
+        let mut avail_features = 1u64 << VIRTIO_F_VERSION_1 | 1u64 << VIRTIO_F_IN_ORDER;
+
+        if iommu {
+            avail_features |= 1u64 << VIRTIO_F_IOMMU_PLATFORM;
+        }
 
         Ok(Vsock {
             cid,
diff --git a/vm-virtio/src/vsock/mod.rs b/vm-virtio/src/vsock/mod.rs
index db0b1f831..c5c343479 100644
--- a/vm-virtio/src/vsock/mod.rs
+++ b/vm-virtio/src/vsock/mod.rs
@@ -256,7 +256,7 @@ mod tests {
                 cid: CID,
                 mem: GuestMemoryMmap::new(&[(GuestAddress(0), MEM_SIZE)]).unwrap(),
                 mem_size: MEM_SIZE,
-                device: Vsock::new(CID, TestBackend::new()).unwrap(),
+                device: Vsock::new(CID, TestBackend::new(), false).unwrap(),
             }
         }
 
diff --git a/vmm/src/device_manager.rs b/vmm/src/device_manager.rs
index 9855fb846..3f53ee65e 100644
--- a/vmm/src/device_manager.rs
+++ b/vmm/src/device_manager.rs
@@ -860,7 +860,7 @@ impl DeviceManager {
                     vm_virtio::vsock::VsockUnixBackend::new(vsock_cfg.cid, socket_path.to_string())
                         .map_err(DeviceManagerError::CreateVsockBackend)?;
 
-                let vsock_device = vm_virtio::Vsock::new(vsock_cfg.cid, backend)
+                let vsock_device = vm_virtio::Vsock::new(vsock_cfg.cid, backend, false)
                     .map_err(DeviceManagerError::CreateVirtioVsock)?;
 
                 devices.push(Box::new(vsock_device) as Box<dyn vm_virtio::VirtioDevice>);