vmm: api: Implement API support for migration

Add API entry points with stub implementation for sending and receiving
a VM from one VMM to another.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

vmm/src/api/http.rs

@@ -100,6 +100,12 @@ pub enum HttpError {
 
     /// Could not get counters from VM
     VmCounters(ApiError),
+
+    /// Error setting up migration received
+    VmReceiveMigration(ApiError),
+
+    /// Error setting up migration sender
+    VmSendMigration(ApiError),
 }
 
 impl From<serde_json::Error> for HttpError {
@@ -205,11 +211,13 @@ lazy_static! {
         r.routes.insert(endpoint!("/vm.info"), Box::new(VmInfo {}));
         r.routes.insert(endpoint!("/vm.pause"), Box::new(VmActionHandler::new(VmAction::Pause)));
         r.routes.insert(endpoint!("/vm.reboot"), Box::new(VmActionHandler::new(VmAction::Reboot)));
+        r.routes.insert(endpoint!("/vm.receive-migration"), Box::new(VmActionHandler::new(VmAction::ReceiveMigration(Arc::default()))));
         r.routes.insert(endpoint!("/vm.remove-device"), Box::new(VmActionHandler::new(VmAction::RemoveDevice(Arc::default()))));
         r.routes.insert(endpoint!("/vm.resize"), Box::new(VmActionHandler::new(VmAction::Resize(Arc::default()))));
         r.routes.insert(endpoint!("/vm.resize-zone"), Box::new(VmActionHandler::new(VmAction::ResizeZone(Arc::default()))));
         r.routes.insert(endpoint!("/vm.restore"), Box::new(VmActionHandler::new(VmAction::Restore(Arc::default()))));
         r.routes.insert(endpoint!("/vm.resume"), Box::new(VmActionHandler::new(VmAction::Resume)));
+        r.routes.insert(endpoint!("/vm.send-migration"), Box::new(VmActionHandler::new(VmAction::SendMigration(Arc::default()))));
         r.routes.insert(endpoint!("/vm.shutdown"), Box::new(VmActionHandler::new(VmAction::Shutdown)));
         r.routes.insert(endpoint!("/vm.snapshot"), Box::new(VmActionHandler::new(VmAction::Snapshot(Arc::default()))));
         r.routes.insert(endpoint!("/vmm.ping"), Box::new(VmmPing {}));

vmm/src/api/http_endpoint.rs

@@ -6,9 +6,9 @@
 use crate::api::http::{error_response, EndpointHandler, HttpError};
 use crate::api::{
     vm_add_device, vm_add_disk, vm_add_fs, vm_add_net, vm_add_pmem, vm_add_vsock, vm_boot,
-    vm_counters, vm_create, vm_delete, vm_info, vm_pause, vm_reboot, vm_remove_device, vm_resize,
-    vm_resize_zone, vm_restore, vm_resume, vm_shutdown, vm_snapshot, vmm_ping, vmm_shutdown,
-    ApiRequest, VmAction, VmConfig,
+    vm_counters, vm_create, vm_delete, vm_info, vm_pause, vm_reboot, vm_receive_migration,
+    vm_remove_device, vm_resize, vm_resize_zone, vm_restore, vm_resume, vm_send_migration,
+    vm_shutdown, vm_snapshot, vmm_ping, vmm_shutdown, ApiRequest, VmAction, VmConfig,
 };
 use micro_http::{Body, Method, Request, Response, StatusCode, Version};
 use std::sync::mpsc::Sender;
@@ -153,6 +153,20 @@ impl EndpointHandler for VmActionHandler {
                 )
                 .map_err(HttpError::VmSnapshot),
 
+                ReceiveMigration(_) => vm_receive_migration(
+                    api_notifier,
+                    api_sender,
+                    Arc::new(serde_json::from_slice(body.raw())?),
+                )
+                .map_err(HttpError::VmReceiveMigration),
+
+                SendMigration(_) => vm_send_migration(
+                    api_notifier,
+                    api_sender,
+                    Arc::new(serde_json::from_slice(body.raw())?),
+                )
+                .map_err(HttpError::VmSendMigration),
+
                 _ => Err(HttpError::BadRequest),
             }
         } else {

vmm/src/api/mod.rs

@@ -44,6 +44,7 @@ use micro_http::Body;
 use std::io;
 use std::sync::mpsc::{channel, RecvError, SendError, Sender};
 use std::sync::{Arc, Mutex};
+use vm_migration::MigratableError;
 use vmm_sys_util::eventfd::EventFd;
 
 /// API errors are sent back from the VMM API server through the ApiResponse.
@@ -138,6 +139,12 @@ pub enum ApiError {
 
     /// The vsock device could not be added to the VM.
     VmAddVsock(VmError),
+
+    /// Error starting migration receiever
+    VmReceiveMigration(MigratableError),
+
+    /// Error starting migration sender
+    VmSendMigration(MigratableError),
 }
 pub type ApiResult<T> = std::result::Result<T, ApiError>;
 
@@ -177,6 +184,18 @@ pub struct VmSnapshotConfig {
     pub destination_url: String,
 }
 
+#[derive(Clone, Deserialize, Serialize, Default)]
+pub struct VmReceiveMigrationData {
+    /// URL for the reception of migration state
+    pub receiver_url: String,
+}
+
+#[derive(Clone, Deserialize, Serialize, Default)]
+pub struct VmSendMigrationData {
+    /// URL to migrate the VM to
+    pub destination_url: String,
+}
+
 pub enum ApiResponsePayload {
     /// No data is sent on the channel.
     Empty,
@@ -275,6 +294,12 @@ pub enum ApiRequest {
 
     /// Restore from a VM snapshot
     VmRestore(Arc<RestoreConfig>, Sender<ApiResponse>),
+
+    /// Incoming migration
+    VmReceiveMigration(Arc<VmReceiveMigrationData>, Sender<ApiResponse>),
+
+    /// Outgoing migration
+    VmSendMigration(Arc<VmSendMigrationData>, Sender<ApiResponse>),
 }
 
 pub fn vm_create(
@@ -352,6 +377,12 @@ pub enum VmAction {
 
     /// Snapshot VM
     Snapshot(Arc<VmSnapshotConfig>),
+
+    /// Incoming migration
+    ReceiveMigration(Arc<VmReceiveMigrationData>),
+
+    /// Outgoing migration
+    SendMigration(Arc<VmSendMigrationData>),
 }
 
 fn vm_action(
@@ -381,6 +412,8 @@ fn vm_action(
         ResizeZone(v) => ApiRequest::VmResizeZone(v, response_sender),
         Restore(v) => ApiRequest::VmRestore(v, response_sender),
         Snapshot(v) => ApiRequest::VmSnapshot(v, response_sender),
+        ReceiveMigration(v) => ApiRequest::VmReceiveMigration(v, response_sender),
+        SendMigration(v) => ApiRequest::VmSendMigration(v, response_sender),
     };
 
     // Send the VM request.
@@ -424,6 +457,22 @@ pub fn vm_counters(api_evt: EventFd, api_sender: Sender<ApiRequest>) -> ApiResul
     vm_action(api_evt, api_sender, VmAction::Counters)
 }
 
+pub fn vm_receive_migration(
+    api_evt: EventFd,
+    api_sender: Sender<ApiRequest>,
+    data: Arc<VmReceiveMigrationData>,
+) -> ApiResult<Option<Body>> {
+    vm_action(api_evt, api_sender, VmAction::ReceiveMigration(data))
+}
+
+pub fn vm_send_migration(
+    api_evt: EventFd,
+    api_sender: Sender<ApiRequest>,
+    data: Arc<VmSendMigrationData>,
+) -> ApiResult<Option<Body>> {
+    vm_action(api_evt, api_sender, VmAction::SendMigration(data))
+}
+
 pub fn vm_snapshot(
     api_evt: EventFd,
     api_sender: Sender<ApiRequest>,

vmm/src/lib.rs

@@ -22,7 +22,10 @@ extern crate vmm_sys_util;
 #[macro_use]
 extern crate credibility;
 
-use crate::api::{ApiError, ApiRequest, ApiResponse, ApiResponsePayload, VmInfo, VmmPingResponse};
+use crate::api::{
+    ApiError, ApiRequest, ApiResponse, ApiResponsePayload, VmInfo, VmReceiveMigrationData,
+    VmSendMigrationData, VmmPingResponse,
+};
 use crate::config::{
     DeviceConfig, DiskConfig, FsConfig, NetConfig, PmemConfig, RestoreConfig, VmConfig, VsockConfig,
 };
@@ -39,7 +42,7 @@ use std::sync::mpsc::{Receiver, RecvError, SendError, Sender};
 use std::sync::{Arc, Mutex};
 use std::{result, thread};
 use thiserror::Error;
-use vm_migration::{Pausable, Snapshottable, Transportable};
+use vm_migration::{MigratableError, Pausable, Snapshottable, Transportable};
 use vmm_sys_util::eventfd::EventFd;
 
 pub mod api;
@@ -639,6 +642,25 @@ impl Vmm {
         }
     }
 
+    fn vm_receive_migration(
+        &mut self,
+        receive_data_migration: VmReceiveMigrationData,
+    ) -> result::Result<(), MigratableError> {
+        info!(
+            "Migration Receiver: {}",
+            receive_data_migration.receiver_url
+        );
+        Ok(())
+    }
+
+    fn vm_send_migration(
+        &mut self,
+        send_data_migration: VmSendMigrationData,
+    ) -> result::Result<(), MigratableError> {
+        info!("Migration Sender: {}", send_data_migration.destination_url);
+        Ok(())
+    }
+
     fn control_loop(&mut self, api_receiver: Arc<Receiver<ApiRequest>>) -> Result<()> {
         const EPOLL_EVENTS_LEN: usize = 100;
 
@@ -878,6 +900,22 @@ impl Vmm {
 
                                     sender.send(response).map_err(Error::ApiResponseSend)?;
                                 }
+                                ApiRequest::VmReceiveMigration(receive_migration_data, sender) => {
+                                    let response = self
+                                        .vm_receive_migration(
+                                            receive_migration_data.as_ref().clone(),
+                                        )
+                                        .map_err(ApiError::VmReceiveMigration)
+                                        .map(|_| ApiResponsePayload::Empty);
+                                    sender.send(response).map_err(Error::ApiResponseSend)?;
+                                }
+                                ApiRequest::VmSendMigration(send_migration_data, sender) => {
+                                    let response = self
+                                        .vm_send_migration(send_migration_data.as_ref().clone())
+                                        .map_err(ApiError::VmSendMigration)
+                                        .map(|_| ApiResponsePayload::Empty);
+                                    sender.send(response).map_err(Error::ApiResponseSend)?;
+                                }
                             }
                         }
                     }