virtio-devices: Version state structures

Version the state for device state for the virtio devices.

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

virtio-devices/src/block.rs

@@ -31,8 +31,11 @@ use std::sync::atomic::{AtomicBool, AtomicU64, Ordering};
 use std::sync::{Arc, Barrier};
 use std::thread;
 use std::{collections::HashMap, convert::TryInto};
+use versionize::{VersionMap, Versionize, VersionizeResult};
+use versionize_derive::Versionize;
 use virtio_bindings::bindings::virtio_blk::*;
 use vm_memory::{ByteValued, Bytes, GuestAddressSpace, GuestMemoryAtomic, GuestMemoryMmap};
+use vm_migration::VersionMapped;
 use vm_migration::{Migratable, MigratableError, Pausable, Snapshot, Snapshottable, Transportable};
 use vmm_sys_util::eventfd::EventFd;
 
@@ -363,7 +366,7 @@ pub struct Block {
     rate_limiter_config: Option<RateLimiterConfig>,
 }
 
-#[derive(Serialize, Deserialize)]
+#[derive(Serialize, Deserialize, Versionize)]
 pub struct BlockState {
     pub disk_path: String,
     pub disk_nsectors: u64,
@@ -372,6 +375,8 @@ pub struct BlockState {
     pub config: VirtioBlockConfig,
 }
 
+impl VersionMapped for BlockState {}
+
 impl Block {
     /// Create a new virtio block device that operates on the given file.
     #[allow(clippy::too_many_arguments)]
@@ -674,11 +679,11 @@ impl Snapshottable for Block {
     }
 
     fn snapshot(&mut self) -> std::result::Result<Snapshot, MigratableError> {
-        Snapshot::new_from_state(&self.id(), &self.state())
+        Snapshot::new_from_versioned_state(&self.id(), &self.state())
     }
 
     fn restore(&mut self, snapshot: Snapshot) -> std::result::Result<(), MigratableError> {
-        self.set_state(&snapshot.to_state(&self.id)?);
+        self.set_state(&snapshot.to_versioned_state(&self.id)?);
         Ok(())
     }
 }