[dpdk-dev] [PATCH v2 2/5] net/virtio: add interrupt configure for vdev

[Jianfeng Tan]

For virtio PCI devices, interrupt should be configured before setting
VIRTIO_CONFIG_STATUS_DRIVER_OK so that QEMU can properly set eventfds
in the host.

For virtio virtual devices, VIRTIO_CONFIG_STATUS_DRIVER_OK should be
set firstly, so that intr_handle is initialized in
virtio_user_start_device().

To accommodate both requirements, we rearrange the sequence like this:
  a. set interrupt configure for PCI devices.
  b. set VIRTIO_CONFIG_STATUS_DRIVER_OK.
  c. set interrupt configure for virtual devices.

Signed-off-by: Jianfeng Tan <jianfeng.tan at intel.com>
---
 drivers/net/virtio/virtio_ethdev.c | 57 ++++++++++++++++++++++++++++++++++----
 1 file changed, 51 insertions(+), 6 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index d9986ab..f0213ba 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1275,7 +1275,7 @@ virtio_queues_unbind_intr(struct rte_eth_dev *dev)
 }
 
 static int
-virtio_configure_intr(struct rte_eth_dev *dev)
+virtio_configure_intr_pci(struct rte_eth_dev *dev)
 {
 	struct virtio_hw *hw = dev->data->dev_private;
 
@@ -1327,6 +1327,37 @@ virtio_configure_intr(struct rte_eth_dev *dev)
 	return 0;
 }
 
+static int
+virtio_configure_intr_vdev(struct rte_eth_dev *dev)
+{
+	struct virtio_hw *hw = dev->data->dev_private;
+
+	if (!dev->intr_handle->intr_vec) {
+		dev->intr_handle->intr_vec =
+			rte_zmalloc("intr_vec",
+				    hw->max_queue_pairs * sizeof(int), 0);
+		if (!dev->intr_handle->intr_vec) {
+			PMD_INIT_LOG(ERR, "Failed to allocate %u rxq vectors",
+				     hw->max_queue_pairs);
+			return -ENOMEM;
+		}
+	}
+
+	/* Re-register callback to update max_intr */
+	rte_intr_callback_unregister(dev->intr_handle,
+				     virtio_interrupt_handler,
+				     dev);
+	rte_intr_callback_register(dev->intr_handle,
+				   virtio_interrupt_handler,
+				   dev);
+
+	if (virtio_queues_bind_intr(dev) < 0) {
+		PMD_INIT_LOG(ERR, "Failed to bind queue/interrupt");
+		return -1;
+	}
+
+	return 0;
+}
 /* reset device and renegotiate features if needed */
 static int
 virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
@@ -1450,15 +1481,29 @@ virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
 	if (ret < 0)
 		return ret;
 
-	if (eth_dev->data->dev_conf.intr_conf.rxq) {
-		if (virtio_configure_intr(eth_dev) < 0) {
-			PMD_INIT_LOG(ERR, "failed to configure interrupt");
-			return -1;
-		}
+	/* For virtio PCI devices, setup interrupt configuration before
+	 * setting VIRTIO_CONFIG_STATUS_DRIVER_OK, required by QEMU.
+	 */
+	if (pci_dev &&
+	    eth_dev->data->dev_conf.intr_conf.rxq &&
+	    virtio_configure_intr_pci(eth_dev) < 0) {
+		PMD_INIT_LOG(ERR, "failed to configure interrupt");
+		return -1;
 	}
 
 	vtpci_reinit_complete(hw);
 
+	/* For virtio vdev, setup interrupt configuration after
+	 * setting VIRTIO_CONFIG_STATUS_DRIVER_OK, so that intr_handle
+	 * is initialized in virtio_user_start_device().
+	 */
+	if (!pci_dev &&
+	    eth_dev->data->dev_conf.intr_conf.rxq &&
+	    virtio_configure_intr_vdev(eth_dev) < 0) {
+		PMD_INIT_LOG(ERR, "failed to configure interrupt");
+		return -1;
+	}
+
 	if (pci_dev)
 		PMD_INIT_LOG(DEBUG, "port %d vendorID=0x%x deviceID=0x%x",
 			eth_dev->data->port_id, pci_dev->id.vendor_id,
-- 
2.7.4