Refactor the VhostNet virtio device

Split the VhostNet virtio device into generic and specific bits.  Almost
the entire Worker implementation is generic between all vhost devices.
The only non-generic bit is a device-specific ioctl to activate a
virtqueue.

To deal with this add a callback to the Worker's Run function to
activate all the virtqueues after they have been set up.

BUG=chromium:708267
TEST=build and run with a vhost-net enabled kernel and see that
     everything still works

Change-Id: I262c07e4d2c289f9528924ba708d0b88bd0379bb
Signed-off-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/636121
Reviewed-by: Jason Clinton <jclinton@chromium.org>
Reviewed-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/main.rs b/src/main.rs
index d480aff..c538c01 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -52,7 +52,7 @@ enum Error {
     Disk(std::io::Error),
     BlockDeviceNew(sys_util::Error),
     BlockDeviceRootSetup(sys_util::Error),
-    VhostNetDeviceNew(hw::virtio::VhostNetError),
+    VhostNetDeviceNew(hw::virtio::vhost::Error),
     NetDeviceNew(hw::virtio::NetError),
     NetDeviceRootSetup(sys_util::Error),
     MacAddressNeedsNetConfig,
@@ -300,7 +300,7 @@ fn run_config(cfg: Config) -> Result<()> {
     if let Some(host_ip) = cfg.host_ip {
         if let Some(netmask) = cfg.netmask {
             let net_box: Box<hw::virtio::VirtioDevice> = if cfg.vhost_net {
-                Box::new(hw::virtio::VhostNet::new(host_ip, netmask, &guest_mem)
+                Box::new(hw::virtio::vhost::Net::new(host_ip, netmask, &guest_mem)
                                    .map_err(|e| Error::VhostNetDeviceNew(e))?)
             } else {
                 Box::new(hw::virtio::Net::new(host_ip, netmask)