From 280d4fb245b7b1ca3c89f43606e3b19518ad3f26 Mon Sep 17 00:00:00 2001
From: Rob Bradford <robert.bradford@intel.com>
Date: Mon, 30 Nov 2020 09:06:13 +0000
Subject: [PATCH] vmm: Include device tree in vm.info API

The DeviceNode cannot be fully represented as it embeds a Rust style
enum (i.e. with data) which is instead represented by a simple
associative array.

Fixes: #1167

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
---
 vmm/src/api/mod.rs                        |  2 ++
 vmm/src/api/openapi/cloud-hypervisor.yaml | 22 ++++++++++++++++++++++
 vmm/src/device_manager.rs                 |  4 ++++
 vmm/src/lib.rs                            |  3 +++
 vmm/src/vm.rs                             |  5 +++++
 5 files changed, 36 insertions(+)

diff --git a/vmm/src/api/mod.rs b/vmm/src/api/mod.rs
index 9684e3c46..6af762350 100644
--- a/vmm/src/api/mod.rs
+++ b/vmm/src/api/mod.rs
@@ -39,6 +39,7 @@ pub mod http_endpoint;
 use crate::config::{
     DeviceConfig, DiskConfig, FsConfig, NetConfig, PmemConfig, RestoreConfig, VmConfig, VsockConfig,
 };
+use crate::device_tree::DeviceTree;
 use crate::vm::{Error as VmError, VmState};
 use micro_http::Body;
 use std::io;
@@ -153,6 +154,7 @@ pub struct VmInfo {
     pub config: Arc<Mutex<VmConfig>>,
     pub state: VmState,
     pub memory_actual_size: u64,
+    pub device_tree: Option<Arc<Mutex<DeviceTree>>>,
 }
 
 #[derive(Clone, Deserialize, Serialize)]
diff --git a/vmm/src/api/openapi/cloud-hypervisor.yaml b/vmm/src/api/openapi/cloud-hypervisor.yaml
index 06a9bb3f5..dbadba734 100644
--- a/vmm/src/api/openapi/cloud-hypervisor.yaml
+++ b/vmm/src/api/openapi/cloud-hypervisor.yaml
@@ -363,8 +363,30 @@ components:
         memory_actual_size:
           type: integer
           format: int64
+        device_tree:
+          type: object
+          additionalProperties:
+            $ref: '#/components/schemas/DeviceNode'
       description: Virtual Machine information
 
+    DeviceNode:
+      type: object
+      properties:
+        id:
+          type: string
+        resources:
+          type: array
+          items:
+            # Rust enum type (with data) which can't be better represented here
+            type: object
+        children:
+          type: array
+          items:
+            type: string
+        pci_bdf:
+          type: integer
+          format: int32
+        
     VmCounters:
       type: object
       additionalProperties:
diff --git a/vmm/src/device_manager.rs b/vmm/src/device_manager.rs
index 2c6482c08..783b19672 100644
--- a/vmm/src/device_manager.rs
+++ b/vmm/src/device_manager.rs
@@ -3134,6 +3134,10 @@ impl DeviceManager {
 
         0
     }
+
+    pub fn device_tree(&self) -> Arc<Mutex<DeviceTree>> {
+        self.device_tree.clone()
+    }
 }
 
 #[cfg(feature = "acpi")]
diff --git a/vmm/src/lib.rs b/vmm/src/lib.rs
index 7f3396828..769833869 100644
--- a/vmm/src/lib.rs
+++ b/vmm/src/lib.rs
@@ -484,10 +484,13 @@ impl Vmm {
                     memory_actual_size -= vm.balloon_size();
                 }
 
+                let device_tree = self.vm.as_ref().map(|vm| vm.device_tree());
+
                 Ok(VmInfo {
                     config,
                     state,
                     memory_actual_size,
+                    device_tree,
                 })
             }
             None => Err(VmError::VmNotCreated),
diff --git a/vmm/src/vm.rs b/vmm/src/vm.rs
index 2751f6bd7..20c16dfdc 100644
--- a/vmm/src/vm.rs
+++ b/vmm/src/vm.rs
@@ -30,6 +30,7 @@ use crate::config::{
 };
 use crate::cpu;
 use crate::device_manager::{self, get_win_size, Console, DeviceManager, DeviceManagerError};
+use crate::device_tree::DeviceTree;
 use crate::memory_manager::{Error as MemoryManagerError, MemoryManager};
 use crate::migration::{get_vm_snapshot, url_to_path, VM_SNAPSHOT_FILE};
 use crate::seccomp_filters::{get_seccomp_filter, Thread};
@@ -1717,6 +1718,10 @@ impl Vm {
             .unwrap()
             .dirty_memory_range_table()
     }
+
+    pub fn device_tree(&self) -> Arc<Mutex<DeviceTree>> {
+        self.device_manager.lock().unwrap().device_tree()
+    }
 }
 
 impl Pausable for Vm {