mock: add a generic version of create_queue

This will allow to reuse the same tests for QueueState and
QueueStateSync.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: bonzini

crates/devices/virtio-blk/src/request.rs

@@ -256,6 +256,7 @@ mod tests {
 
     use virtio_queue::defs::{VIRTQ_DESC_F_NEXT, VIRTQ_DESC_F_WRITE};
     use virtio_queue::mock::MockSplitQueue;
+    use virtio_queue::{Queue, QueueState};
 
     impl PartialEq for Error {
         fn eq(&self, other: &Self) -> bool {
@@ -330,7 +331,8 @@ mod tests {
         mem.write_obj(1u16, vq.avail_addr().unchecked_add(2))
             .unwrap();
 
-        vq.create_queue(mem)
+        let mut q: Queue<_, QueueState> = vq.as_queue(mem);
+        q
             .iter()
             .unwrap()
             .next()

crates/virtio-queue/src/lib.rs

@@ -1313,7 +1313,7 @@ mod tests {
         let m = &GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap();
         let vq = MockSplitQueue::new(m, 16);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
 
         // q is currently valid
         assert!(q.is_valid());
@@ -1425,7 +1425,7 @@ mod tests {
         let m = &GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap();
         let vq = MockSplitQueue::new(m, 16);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
 
         // q is currently valid
         assert!(q.is_valid());
@@ -1487,7 +1487,7 @@ mod tests {
         let m = &GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap();
         let vq = MockSplitQueue::new(m, 16);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
 
         assert_eq!(vq.used().idx().load(), 0);
 
@@ -1510,7 +1510,7 @@ mod tests {
         let m = &GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap();
         let vq = MockSplitQueue::new(m, 16);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
         q.state.size = 8;
         q.state.ready = true;
         q.state.reset();
@@ -1524,7 +1524,7 @@ mod tests {
         let qsize = 16;
         let vq = MockSplitQueue::new(m, qsize);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
         let avail_addr = vq.avail_addr();
 
         // It should always return true when EVENT_IDX isn't enabled.
@@ -1569,7 +1569,7 @@ mod tests {
         let m = &GuestMemoryMmap::<()>::from_ranges(&[(GuestAddress(0), 0x10000)]).unwrap();
         let vq = MockSplitQueue::new(m, 16);
 
-        let mut q = vq.create_queue(m);
+        let mut q: Queue<_, QueueState> = vq.as_queue(m);
         let used_addr = vq.used_addr();
 
         assert_eq!(q.state.event_idx_enabled, false);

crates/virtio-queue/src/mock.rs

@@ -12,7 +12,7 @@ use vm_memory::{
 };
 
 use crate::defs::{VIRTQ_DESC_F_INDIRECT, VIRTQ_DESC_F_NEXT};
-use crate::{Descriptor, Queue, QueueState};
+use crate::{Descriptor, Queue, QueueState, QueueStateT};
 
 /// Wrapper struct used for accesing a particular address of a GuestMemory area.
 pub struct Ref<'a, M, T> {
@@ -364,16 +364,23 @@ impl<'a, M: GuestMemory> MockSplitQueue<'a, M> {
         self.update_avail_idx(head_idx);
     }
 
+    /// Return a QueueStateT implementation for this queue.
+    pub fn as_queue<A: GuestAddressSpace, T: QueueStateT>(&self, a: A) -> Queue<A, T> {
+        let mut q = Queue::<A, T>::new(a, self.len);
+        {
+            let mut inner = q.state.lock();
+            inner.size = self.len;
+            inner.ready = true;
+            inner.desc_table = self.desc_table_addr;
+            inner.avail_ring = self.avail_addr;
+            inner.used_ring = self.used_addr;
+        }
+        q
+    }
+
     /// Creates a new `Queue`, using the underlying memory regions represented
     /// by the `MockSplitQueue`.
     pub fn create_queue<A: GuestAddressSpace>(&self, a: A) -> Queue<A, QueueState> {
-        let mut q = Queue::<A, QueueState>::new(a, self.len);
-
-        q.state.size = self.len;
-        q.state.ready = true;
-        q.state.desc_table = self.desc_table_addr;
-        q.state.avail_ring = self.avail_addr;
-        q.state.used_ring = self.used_addr;
-        q
+        self.as_queue(a)
     }
 }