From 57f532a7604e02757439937ec5032c5ae910ef05 Mon Sep 17 00:00:00 2001
From: Rob Bradford <robert.bradford@intel.com>
Date: Tue, 1 Jun 2021 09:30:03 +0000
Subject: [PATCH] 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                                 |  3 --
 virtio-devices/src/transport/pci_device.rs | 33 ++++++++++++++++++----
 vm-virtio/Cargo.toml                       |  3 --
 vm-virtio/src/lib.rs                       |  2 --
 vm-virtio/src/queue.rs                     | 10 +------
 5 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 8c5f4256b..a04efad81 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1255,9 +1255,6 @@ name = "vm-virtio"
 version = "0.1.0"
 dependencies = [
  "log",
- "serde",
- "serde_derive",
- "serde_json",
  "virtio-bindings",
  "vm-memory",
 ]
diff --git a/virtio-devices/src/transport/pci_device.rs b/virtio-devices/src/transport/pci_device.rs
index 50bfc47b8..b78356117 100644
--- a/virtio-devices/src/transport/pci_device.rs
+++ b/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)
diff --git a/vm-virtio/Cargo.toml b/vm-virtio/Cargo.toml
index 3f434e7f0..900f77446 100644
--- a/vm-virtio/Cargo.toml
+++ b/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"] }
\ No newline at end of file
diff --git a/vm-virtio/src/lib.rs b/vm-virtio/src/lib.rs
index 7ea405750..09575d865 100644
--- a/vm-virtio/src/lib.rs
+++ b/vm-virtio/src/lib.rs
@@ -12,8 +12,6 @@
 
 #[macro_use]
 extern crate log;
-#[macro_use]
-extern crate serde_derive;
 
 use std::fmt;
 
diff --git a/vm-virtio/src/queue.rs b/vm-virtio/src/queue.rs
index bf4d48227..1ee1fead1 100644
--- a/vm-virtio/src/queue.rs
+++ b/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