hypervisor: adjust new function return type

Make them return wrapped trait object directly.

No functional change.

Signed-off-by: Wei Liu <liuwe@microsoft.com>

hypervisor/src/kvm/mod.rs

@@ -905,7 +905,8 @@ pub enum KvmError {
 pub type KvmResult<T> = result::Result<T, KvmError>;
 impl KvmHypervisor {
     /// Create a hypervisor based on Kvm
-    pub fn new() -> hypervisor::Result<KvmHypervisor> {
+    #[allow(clippy::new_ret_no_self)]
+    pub fn new() -> hypervisor::Result<Arc<dyn hypervisor::Hypervisor>> {
         let kvm_obj = Kvm::new().map_err(|e| hypervisor::HypervisorError::VmCreate(e.into()))?;
         let api_version = kvm_obj.get_api_version();
 
@@ -913,7 +914,7 @@ impl KvmHypervisor {
             return Err(hypervisor::HypervisorError::IncompatibleApiVersion);
         }
 
-        Ok(KvmHypervisor { kvm: kvm_obj })
+        Ok(Arc::new(KvmHypervisor { kvm: kvm_obj }))
     }
 }
 /// Implementation of Hypervisor trait for KVM

hypervisor/src/lib.rs

@@ -74,7 +74,7 @@ pub fn new() -> std::result::Result<Arc<dyn Hypervisor>, HypervisorError> {
     #[cfg(feature = "mshv")]
     let hv = mshv::MshvHypervisor::new()?;
 
-    Ok(Arc::new(hv))
+    Ok(hv)
 }
 
 // Returns a `Vec<T>` with a size in bytes at least as large as `size_in_bytes`.

hypervisor/src/mshv/mod.rs

@@ -177,10 +177,11 @@ impl MshvHypervisor {
 
 impl MshvHypervisor {
     /// Create a hypervisor based on Mshv
-    pub fn new() -> hypervisor::Result<MshvHypervisor> {
+    #[allow(clippy::new_ret_no_self)]
+    pub fn new() -> hypervisor::Result<Arc<dyn hypervisor::Hypervisor>> {
         let mshv_obj =
             Mshv::new().map_err(|e| hypervisor::HypervisorError::HypervisorCreate(e.into()))?;
-        Ok(MshvHypervisor { mshv: mshv_obj })
+        Ok(Arc::new(MshvHypervisor { mshv: mshv_obj }))
     }
 }
 /// Implementation of Hypervisor trait for Mshv