vmm: Update NUMA node distances internally

Based on the NumaConfig which now provides distance information, we can
internally update the list of NUMA nodes with the exact distances they
should be located from other nodes.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

vmm/src/vm.rs

@@ -195,6 +195,9 @@ pub enum Error {
 
     /// Failed serializing into JSON
     SerializeJson(serde_json::Error),
+
+    /// Invalid configuration for NUMA.
+    InvalidNumaConfig,
 }
 pub type Result<T> = result::Result<T, Error>;
 
@@ -339,12 +342,30 @@ impl Vm {
     ) -> Result<()> {
         let mut mm = memory_manager.lock().unwrap();
         let numa_nodes = mm.numa_nodes_mut();
+        let existing_nodes: Vec<u32> = numa_nodes.keys().cloned().collect();
 
         for config in configs.iter() {
-            if let Some(cpus) = &config.cpus {
-                if let Some(node) = numa_nodes.get_mut(&config.id) {
+            if let Some(node) = numa_nodes.get_mut(&config.id) {
+                if let Some(cpus) = &config.cpus {
                     node.cpus_mut().extend(cpus);
                 }
+
+                if let Some(distances) = &config.distances {
+                    for distance in distances.iter() {
+                        let dest = distance.destination;
+                        let dist = distance.distance;
+
+                        if !existing_nodes.contains(&dest) {
+                            error!("Unknown destination NUMA node {}", dest);
+                            return Err(Error::InvalidNumaConfig);
+                        }
+
+                        node.distances_mut().insert(dest, dist);
+                    }
+                }
+            } else {
+                error!("Unknown NUMA node {}", config.id);
+                return Err(Error::InvalidNumaConfig);
             }
         }