Move Cloud Hypervisor to virtio-queue crate

Relying on the vm-virtio/virtio-queue crate from rust-vmm which has been
copied inside the Cloud Hypervisor tree, the entire codebase is moved to
the new definition of a Queue and other related structures.

The reason for this move is to follow the upstream until we get some
agreement for the patches that we need on top of that to make it
properly work with Cloud Hypervisor.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

virtio-devices/src/device.rs

@@ -6,7 +6,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0 AND BSD-3-Clause
 
-use crate::{ActivateError, ActivateResult, Error, Queue};
+use crate::{ActivateError, ActivateResult, Error};
 use crate::{GuestMemoryMmap, GuestRegionMmap};
 use libc::EFD_NONBLOCK;
 use std::collections::HashMap;
@@ -17,6 +17,7 @@ use std::sync::{
     Arc, Barrier,
 };
 use std::thread;
+use virtio_queue::Queue;
 use vm_memory::{GuestAddress, GuestMemoryAtomic, GuestUsize};
 use vm_migration::{MigratableError, Pausable};
 use vm_virtio::VirtioDeviceType;
@@ -31,9 +32,13 @@ pub trait VirtioInterrupt: Send + Sync {
     fn trigger(
         &self,
         int_type: &VirtioInterruptType,
-        queue: Option<&Queue>,
+        queue: Option<&Queue<GuestMemoryAtomic<GuestMemoryMmap>>>,
     ) -> std::result::Result<(), std::io::Error>;
-    fn notifier(&self, _int_type: &VirtioInterruptType, _queue: Option<&Queue>) -> Option<EventFd> {
+    fn notifier(
+        &self,
+        _int_type: &VirtioInterruptType,
+        _queue: Option<&Queue<GuestMemoryAtomic<GuestMemoryMmap>>>,
+    ) -> Option<EventFd> {
         None
     }
 }
@@ -107,7 +112,7 @@ pub trait VirtioDevice: Send {
         &mut self,
         mem: GuestMemoryAtomic<GuestMemoryMmap>,
         interrupt_evt: Arc<dyn VirtioInterrupt>,
-        queues: Vec<Queue>,
+        queues: Vec<Queue<GuestMemoryAtomic<GuestMemoryMmap>>>,
         queue_evts: Vec<EventFd>,
     ) -> ActivateResult;
 
@@ -247,7 +252,7 @@ impl VirtioCommon {
 
     pub fn activate(
         &mut self,
-        queues: &[Queue],
+        queues: &[Queue<GuestMemoryAtomic<GuestMemoryMmap>>],
         queue_evts: &[EventFd],
         interrupt_cb: &Arc<dyn VirtioInterrupt>,
     ) -> ActivateResult {