This introduces a new version of virtio-blk device. The default
virtio-blk provides synchronous processing of the queues, while this
new version relies on io_uring from the host kernel to provide an
asynchronous processing of the queues.
This new asynchronous version provides a huge performance improvement
compared to the default synchronous version.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Extract the code that is used by vhost_user_block from the
virtio-devices crate to remove the dependencies on unrequired
functionality such as the virtio transports.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Split the generic virtio code (queues and device type) from the
VirtioDevice trait, transport and device implementations.
This also simplifies the feature handling in vhost_user_backend as the
vm-virtio crate is no longer has any features.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>