net/virtio: introduce DMA ops

Add DMA map/unmap callbacks to the virtio_user pmd, which could
be leveraged by vdev bus driver to map memory for backend
devices with DMA capability.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

diff --git a/drivers/net/virtio/virtio_user/vhost.h b/drivers/net/virtio/virtio_user/vhost.h
index 8f49ef4..2e71995 100644 (file)
--- a/drivers/net/virtio/virtio_user/vhost.h
+++ b/drivers/net/virtio/virtio_user/vhost.h
@@ -105,6 +105,10 @@ struct virtio_user_backend_ops {
        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);
 };
 
 extern struct virtio_user_backend_ops virtio_ops_user;

diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
index 87f6cb6..60d17af 100644 (file)
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -818,9 +818,63 @@ virtio_user_pmd_remove(struct rte_vdev_device *vdev)
        return 0;
 }
 
+static int virtio_user_pmd_dma_map(struct rte_vdev_device *vdev, void *addr,
+               uint64_t iova, size_t len)
+{
+       const char *name;
+       struct rte_eth_dev *eth_dev;
+       struct virtio_user_dev *dev;
+       struct virtio_hw *hw;
+
+       if (!vdev)
+               return -EINVAL;
+
+       name = rte_vdev_device_name(vdev);
+       eth_dev = rte_eth_dev_allocated(name);
+       /* Port has already been released by close. */
+       if (!eth_dev)
+               return 0;
+
+       hw = (struct virtio_hw *)eth_dev->data->dev_private;
+       dev = hw->virtio_user_dev;
+
+       if (dev->ops->dma_map)
+               return dev->ops->dma_map(dev, addr, iova, len);
+
+       return 0;
+}
+
+static int virtio_user_pmd_dma_unmap(struct rte_vdev_device *vdev, void *addr,
+               uint64_t iova, size_t len)
+{
+       const char *name;
+       struct rte_eth_dev *eth_dev;
+       struct virtio_user_dev *dev;
+       struct virtio_hw *hw;
+
+       if (!vdev)
+               return -EINVAL;
+
+       name = rte_vdev_device_name(vdev);
+       eth_dev = rte_eth_dev_allocated(name);
+       /* Port has already been released by close. */
+       if (!eth_dev)
+               return 0;
+
+       hw = (struct virtio_hw *)eth_dev->data->dev_private;
+       dev = hw->virtio_user_dev;
+
+       if (dev->ops->dma_unmap)
+               return dev->ops->dma_unmap(dev, addr, iova, len);
+
+       return 0;
+}
+
 static struct rte_vdev_driver virtio_user_driver = {
        .probe = virtio_user_pmd_probe,
        .remove = virtio_user_pmd_remove,
+       .dma_map = virtio_user_pmd_dma_map,
+       .dma_unmap = virtio_user_pmd_dma_unmap,
 };
 
 RTE_PMD_REGISTER_VDEV(net_virtio_user, virtio_user_driver);