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>

vhost_user_net/src/lib.rs

@@ -22,9 +22,8 @@ use std::sync::{Arc, Mutex, RwLock};
 use std::vec::Vec;
 use vhost::vhost_user::message::*;
 use vhost::vhost_user::Listener;
-use vhost_user_backend::{GuestMemoryMmap, VhostUserBackend, VhostUserDaemon, Vring, VringWorker};
+use vhost_user_backend::{VhostUserBackend, VhostUserDaemon, Vring, VringWorker};
 use virtio_bindings::bindings::virtio_net::*;
-use vm_memory::GuestMemoryAtomic;
 use vmm_sys_util::eventfd::EventFd;
 
 pub type Result<T> = std::result::Result<T, Error>;
@@ -81,7 +80,6 @@ impl VhostUserNetThread {
         Ok(VhostUserNetThread {
             kill_evt: EventFd::new(EFD_NONBLOCK).map_err(Error::CreateKillEventFd)?,
             net: NetQueuePair {
-                mem: None,
                 tap_for_write_epoll: tap.clone(),
                 tap,
                 rx: RxVirtio::new(),
@@ -184,13 +182,6 @@ impl VhostUserBackend for VhostUserNetBackend {
 
     fn set_event_idx(&mut self, _enabled: bool) {}
 
-    fn update_memory(&mut self, mem: GuestMemoryMmap) -> VhostUserBackendResult<()> {
-        for thread in self.threads.iter() {
-            thread.lock().unwrap().net.mem = Some(GuestMemoryAtomic::new(mem.clone()));
-        }
-        Ok(())
-    }
-
     fn handle_event(
         &self,
         device_event: u16,