vmm: remove unnecessary Result

On-behalf-of: SAP [email protected]
Signed-off-by: Philipp Schuster <[email protected]>

Author: phip1611

vmm/src/api/mod.rs

@@ -408,7 +408,9 @@ pub trait RequestHandler {
 
     fn vm_nmi(&mut self) -> Result<(), VmError>;
 
-    fn vm_migration_progress(&mut self) -> Result<Option<MigrationProgressAndStatus>, VmError>;
+    /// Returns the progress of the currently active migration or any previous
+    /// failed or canceled migration.
+    fn vm_migration_progress(&mut self) -> Option<MigrationProgressAndStatus>;
 }
 
 /// It would be nice if we could pass around an object like this:
@@ -1552,8 +1554,8 @@ impl ApiAction for VmMigrationProgress {
         Box::new(move |vmm| {
             info!("API request event: VmMigrationProgress");
 
-            let response = vmm
-                .vm_migration_progress()
+            let snapshot = Ok(vmm.vm_migration_progress());
+            let response = snapshot
                 .map(Box::new)
                 .map(ApiResponsePayload::VmMigrationProgress)
                 .map_err(ApiError::VmMigrationProgress);

vmm/src/lib.rs

@@ -3571,14 +3571,9 @@ impl RequestHandler for Vmm {
         Ok(())
     }
 
-    fn vm_migration_progress(
-        &mut self,
-    ) -> result::Result<Option<MigrationProgressAndStatus>, VmError> {
-        // We explicitly do not check here for `is VM running?` to always
-        // enable querying the state of the last failed migration.
+    fn vm_migration_progress(&mut self) -> Option<MigrationProgressAndStatus> {
         let lock = MIGRATION_PROGRESS_SNAPSHOT.lock().unwrap();
-        let maybe_snapshot = lock.clone();
-        Ok(maybe_snapshot)
+        lock.clone()
     }
 }