vm-virtio: Implement multiqueue/multithread support for virtio-blk

This commit improves the existing virtio-blk implementation, allowing
for better I/O performance. The cost for the end user is to accept
allocating more vCPUs to the virtual machine, so that multiple I/O
threads can run in parallel.

One thing to notice, the amount of vCPUs must be egal or superior to the
amount of queues dedicated to the virtio-blk device.

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

vmm/src/device_manager.rs

@@ -991,6 +991,8 @@ impl DeviceManager {
                             disk_cfg.path.clone(),
                             disk_cfg.readonly,
                             disk_cfg.iommu,
+                            disk_cfg.num_queues,
+                            disk_cfg.queue_size,
                         )
                         .map_err(DeviceManagerError::CreateVirtioBlock)?;
 
@@ -1010,6 +1012,8 @@ impl DeviceManager {
                             disk_cfg.path.clone(),
                             disk_cfg.readonly,
                             disk_cfg.iommu,
+                            disk_cfg.num_queues,
+                            disk_cfg.queue_size,
                         )
                         .map_err(DeviceManagerError::CreateVirtioBlock)?;