virtio-devices, vm-virtio: Refactor queue state saving/restoring

Use a separate QueueState structure which can be versioned.

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

Cargo.lock

@@ -1255,9 +1255,6 @@ name = "vm-virtio"
 version = "0.1.0"
 dependencies = [
  "log",
- "serde",
- "serde_derive",
- "serde_json",
  "virtio-bindings",
  "vm-memory",
 ]

virtio-devices/src/transport/pci_device.rs

@@ -260,10 +260,21 @@ const NOTIFY_OFF_MULTIPLIER: u32 = 4; // A dword per notification address.
 const VIRTIO_PCI_VENDOR_ID: u16 = 0x1af4;
 const VIRTIO_PCI_DEVICE_ID_BASE: u16 = 0x1040; // Add to device type to get device ID.
 
+#[derive(Serialize, Deserialize)]
+struct QueueState {
+    max_size: u16,
+    size: u16,
+    ready: bool,
+    vector: u16,
+    desc_table: u64,
+    avail_ring: u64,
+    used_ring: u64,
+}
+
 #[derive(Serialize, Deserialize)]
 struct VirtioPciDeviceState {
     device_activated: bool,
-    queues: Vec<Queue>,
+    queues: Vec<QueueState>,
     interrupt_status: usize,
 }
 
@@ -451,7 +462,19 @@ impl VirtioPciDevice {
         VirtioPciDeviceState {
             device_activated: self.device_activated.load(Ordering::Acquire),
             interrupt_status: self.interrupt_status.load(Ordering::Acquire),
-            queues: self.queues.clone(),
+            queues: self
+                .queues
+                .iter()
+                .map(|q| QueueState {
+                    max_size: q.max_size,
+                    size: q.size,
+                    ready: q.ready,
+                    vector: q.vector,
+                    desc_table: q.desc_table.0,
+                    avail_ring: q.avail_ring.0,
+                    used_ring: q.used_ring.0,
+                })
+                .collect(),
         }
     }
 
@@ -469,9 +492,9 @@ impl VirtioPciDevice {
                 queue.size = state.queues[i].size;
                 queue.ready = state.queues[i].ready;
                 queue.vector = state.queues[i].vector;
-                queue.desc_table = state.queues[i].desc_table;
-                queue.avail_ring = state.queues[i].avail_ring;
-                queue.used_ring = state.queues[i].used_ring;
+                queue.desc_table = GuestAddress(state.queues[i].desc_table);
+                queue.avail_ring = GuestAddress(state.queues[i].avail_ring);
+                queue.used_ring = GuestAddress(state.queues[i].used_ring);
                 queue.next_avail = Wrapping(
                     queue
                         .used_index_from_memory(&mem)

vm-virtio/Cargo.toml

@@ -9,8 +9,5 @@ default = []
 
 [dependencies]
 log = "0.4.14"
-serde = ">=1.0.27"
-serde_derive = ">=1.0.27"
-serde_json = ">=1.0.9"
 virtio-bindings = { version = "0.1", features = ["virtio-v5_0_0"]}
 vm-memory = { version = "0.5.0", features = ["backend-mmap", "backend-atomic"] }

vm-virtio/src/lib.rs

@@ -12,8 +12,6 @@
 
 #[macro_use]
 extern crate log;
-#[macro_use]
-extern crate serde_derive;
 
 use std::fmt;
 

vm-virtio/src/queue.rs

@@ -384,11 +384,7 @@ impl<'a, 'b> Iterator for AvailIter<'a, 'b> {
     }
 }
 
-#[derive(Serialize, Deserialize)]
-#[serde(remote = "GuestAddress")]
-struct GuestAddressDef(pub u64);
-
-#[derive(Clone, Serialize, Deserialize)]
+#[derive(Clone)]
 /// A virtio queue's parameters.
 pub struct Queue {
     /// The maximal size in elements offered by the device
@@ -403,22 +399,18 @@ pub struct Queue {
     /// Interrupt vector index of the queue
     pub vector: u16,
 
-    #[serde(with = "GuestAddressDef")]
     /// Guest physical address of the descriptor table
     pub desc_table: GuestAddress,
 
-    #[serde(with = "GuestAddressDef")]
     /// Guest physical address of the available ring
     pub avail_ring: GuestAddress,
 
-    #[serde(with = "GuestAddressDef")]
     /// Guest physical address of the used ring
     pub used_ring: GuestAddress,
 
     pub next_avail: Wrapping<u16>,
     pub next_used: Wrapping<u16>,
 
-    #[serde(skip)]
     pub iommu_mapping_cb: Option<Arc<VirtioIommuRemapping>>,
 
     /// VIRTIO_F_RING_EVENT_IDX negotiated