[PATCH v1 18/21] net/virtio-user: add new callback to enable control queue

[Maxime Coquelin <maxime.coquelin@redhat.com>]

This patch introduces a new callback that is to be called
when the backend supports control virtqueue.

Implementation for Vhost-vDPA backend is added in this patch.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/net/virtio/virtio_user/vhost.h           |  1 +
 drivers/net/virtio/virtio_user/vhost_vdpa.c      | 15 +++++++++++++++
 drivers/net/virtio/virtio_user/virtio_user_dev.c |  3 +++
 3 files changed, 19 insertions(+)

diff --git a/drivers/net/virtio/virtio_user/vhost.h b/drivers/net/virtio/virtio_user/vhost.h
index dfbf6be033..f817cab77a 100644
--- a/drivers/net/virtio/virtio_user/vhost.h
+++ b/drivers/net/virtio/virtio_user/vhost.h
@@ -82,6 +82,7 @@ struct virtio_user_backend_ops {
 	int (*get_config)(struct virtio_user_dev *dev, uint8_t *data, uint32_t off, uint32_t len);
 	int (*set_config)(struct virtio_user_dev *dev, const uint8_t *data, uint32_t off,
 			uint32_t len);
+	int (*cvq_enable)(struct virtio_user_dev *dev, int enable);
 	int (*enable_qp)(struct virtio_user_dev *dev, uint16_t pair_idx, int enable);
 	int (*dma_map)(struct virtio_user_dev *dev, void *addr, uint64_t iova, size_t len);
 	int (*dma_unmap)(struct virtio_user_dev *dev, void *addr, uint64_t iova, size_t len);
diff --git a/drivers/net/virtio/virtio_user/vhost_vdpa.c b/drivers/net/virtio/virtio_user/vhost_vdpa.c
index a0897f8dd1..3fd13d9fac 100644
--- a/drivers/net/virtio/virtio_user/vhost_vdpa.c
+++ b/drivers/net/virtio/virtio_user/vhost_vdpa.c
@@ -564,6 +564,20 @@ vhost_vdpa_destroy(struct virtio_user_dev *dev)
 	return 0;
 }
 
+static int
+vhost_vdpa_cvq_enable(struct virtio_user_dev *dev, int enable)
+{
+	struct vhost_vring_state state = {
+		.index = dev->max_queue_pairs * 2,
+		.num   = enable,
+	};
+
+	if (vhost_vdpa_set_vring_enable(dev, &state))
+		return -1;
+
+	return 0;
+}
+
 static int
 vhost_vdpa_enable_queue_pair(struct virtio_user_dev *dev,
 			       uint16_t pair_idx,
@@ -629,6 +643,7 @@ struct virtio_user_backend_ops virtio_ops_vdpa = {
 	.set_status = vhost_vdpa_set_status,
 	.get_config = vhost_vdpa_get_config,
 	.set_config = vhost_vdpa_set_config,
+	.cvq_enable = vhost_vdpa_cvq_enable,
 	.enable_qp = vhost_vdpa_enable_queue_pair,
 	.dma_map = vhost_vdpa_dma_map_batch,
 	.dma_unmap = vhost_vdpa_dma_unmap_batch,
diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
index 1a5386a3f6..b0d603ee12 100644
--- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
+++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
@@ -767,6 +767,9 @@ virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
 	for (i = q_pairs; i < dev->max_queue_pairs; ++i)
 		ret |= dev->ops->enable_qp(dev, i, 0);
 
+	if (dev->scvq)
+		ret |= dev->ops->cvq_enable(dev, 1);
+
 	dev->queue_pairs = q_pairs;
 
 	return ret;
-- 
2.38.1