[dpdk-dev] [PATCH v4 04/44] net/virtio: introduce Virtio bus type

[Maxime Coquelin]

This patch is preliminary work for introducing a bus layer
in Virtio PMD, in order to improve Virtio-user integration.

A new bus type is added to provide a unified way to distinguish
which bus type is used (PCI modern, PCI legacy or Virtio-user).

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia at intel.com>
---
 drivers/net/virtio/virtio_ethdev.c      | 40 +++++++++++++------------
 drivers/net/virtio/virtio_pci.c         |  4 +--
 drivers/net/virtio/virtio_pci.h         |  9 +++++-
 drivers/net/virtio/virtio_user_ethdev.c |  2 +-
 4 files changed, 32 insertions(+), 23 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 92a3d4efa5..0ba10c274a 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -592,9 +592,9 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t vtpci_queue_idx)
 	 * we use virtual address. And we need properly set _offset_, please see
 	 * VIRTIO_MBUF_DATA_DMA_ADDR in virtqueue.h for more information.
 	 */
-	if (!hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN) {
 		vq->offset = offsetof(struct rte_mbuf, buf_iova);
-	else {
+	} else if (hw->bus_type == VIRTIO_BUS_USER) {
 		vq->vq_ring_mem = (uintptr_t)mz->addr;
 		vq->offset = offsetof(struct rte_mbuf, buf_addr);
 		if (queue_type == VTNET_TQ)
@@ -746,13 +746,13 @@ virtio_dev_close(struct rte_eth_dev *dev)
 	virtio_free_queues(hw);
 
 #ifdef RTE_VIRTIO_USER
-	if (hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_USER)
 		virtio_user_dev_uninit(hw->virtio_user_dev);
 	else
 #endif
 	if (dev->device) {
 		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(dev));
-		if (!hw->modern)
+		if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY)
 			rte_pci_ioport_unmap(VTPCI_IO(hw));
 	}
 
@@ -1299,7 +1299,7 @@ virtio_intr_unmask(struct rte_eth_dev *dev)
 	if (rte_intr_ack(dev->intr_handle) < 0)
 		return -1;
 
-	if (!hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN)
 		hw->use_msix = vtpci_msix_detect(RTE_ETH_DEV_TO_PCI(dev));
 
 	return 0;
@@ -1313,7 +1313,7 @@ virtio_intr_enable(struct rte_eth_dev *dev)
 	if (rte_intr_enable(dev->intr_handle) < 0)
 		return -1;
 
-	if (!hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN)
 		hw->use_msix = vtpci_msix_detect(RTE_ETH_DEV_TO_PCI(dev));
 
 	return 0;
@@ -1327,7 +1327,7 @@ virtio_intr_disable(struct rte_eth_dev *dev)
 	if (rte_intr_disable(dev->intr_handle) < 0)
 		return -1;
 
-	if (!hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN)
 		hw->use_msix = vtpci_msix_detect(RTE_ETH_DEV_TO_PCI(dev));
 
 	return 0;
@@ -1368,13 +1368,13 @@ virtio_negotiate_features(struct virtio_hw *hw, uint64_t req_features)
 	PMD_INIT_LOG(DEBUG, "features after negotiate = %" PRIx64,
 		hw->guest_features);
 
-	if (hw->modern && !vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) {
+	if (hw->bus_type == VIRTIO_BUS_PCI_MODERN && !vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) {
 		PMD_INIT_LOG(ERR,
 			"VIRTIO_F_VERSION_1 features is not enabled.");
 		return -1;
 	}
 
-	if (hw->modern || hw->virtio_user_dev) {
+	if (hw->bus_type == VIRTIO_BUS_PCI_MODERN || hw->bus_type == VIRTIO_BUS_USER) {
 		vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_FEATURES_OK);
 		if (!(vtpci_get_status(hw) & VIRTIO_CONFIG_STATUS_FEATURES_OK)) {
 			PMD_INIT_LOG(ERR,
@@ -1709,7 +1709,7 @@ virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
 
 	hw->weak_barriers = !vtpci_with_feature(hw, VIRTIO_F_ORDER_PLATFORM);
 
-	if (!hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN)
 		pci_dev = RTE_ETH_DEV_TO_PCI(eth_dev);
 
 	/* If host does not support both status and MSI-X then disable LSC */
@@ -1856,7 +1856,7 @@ virtio_init_device(struct rte_eth_dev *eth_dev, uint64_t req_features)
 static int
 virtio_remap_pci(struct rte_pci_device *pci_dev, struct virtio_hw *hw)
 {
-	if (hw->modern) {
+	if (hw->bus_type == VIRTIO_BUS_PCI_MODERN) {
 		/*
 		 * We don't have to re-parse the PCI config space, since
 		 * rte_pci_map_device() makes sure the mapped address
@@ -1872,7 +1872,7 @@ virtio_remap_pci(struct rte_pci_device *pci_dev, struct virtio_hw *hw)
 			PMD_INIT_LOG(DEBUG, "failed to map pci device!");
 			return -1;
 		}
-	} else {
+	} else if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY) {
 		if (rte_pci_ioport_map(pci_dev, 0, VTPCI_IO(hw)) < 0)
 			return -1;
 	}
@@ -1884,14 +1884,16 @@ static void
 virtio_set_vtpci_ops(struct virtio_hw *hw)
 {
 #ifdef RTE_VIRTIO_USER
-	if (hw->virtio_user_dev)
+	if (hw->bus_type == VIRTIO_BUS_USER)
 		VTPCI_OPS(hw) = &virtio_user_ops;
 	else
 #endif
-	if (hw->modern)
+	if (hw->bus_type == VIRTIO_BUS_PCI_MODERN)
 		VTPCI_OPS(hw) = &modern_ops;
-	else
+	else if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY)
 		VTPCI_OPS(hw) = &legacy_ops;
+
+	return;
 }
 
 /*
@@ -1919,7 +1921,7 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	eth_dev->rx_descriptor_done = virtio_dev_rx_queue_done;
 
 	if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
-		if (!hw->virtio_user_dev) {
+		if (hw->bus_type != VIRTIO_BUS_USER) {
 			ret = virtio_remap_pci(RTE_ETH_DEV_TO_PCI(eth_dev), hw);
 			if (ret)
 				return ret;
@@ -1950,7 +1952,7 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	/* For virtio_user case the hw->virtio_user_dev is populated by
 	 * virtio_user_eth_dev_alloc() before eth_virtio_dev_init() is called.
 	 */
-	if (!hw->virtio_user_dev) {
+	if (hw->bus_type != VIRTIO_BUS_USER) {
 		ret = vtpci_init(RTE_ETH_DEV_TO_PCI(eth_dev), hw);
 		if (ret)
 			goto err_vtpci_init;
@@ -1982,9 +1984,9 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
 	return 0;
 
 err_virtio_init:
-	if (!hw->virtio_user_dev) {
+	if (hw->bus_type == VIRTIO_BUS_PCI_MODERN || hw->bus_type == VIRTIO_BUS_PCI_LEGACY) {
 		rte_pci_unmap_device(RTE_ETH_DEV_TO_PCI(eth_dev));
-		if (!hw->modern)
+		if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY)
 			rte_pci_ioport_unmap(VTPCI_IO(hw));
 	}
 err_vtpci_init:
diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c
index d6b950ee69..1692268f30 100644
--- a/drivers/net/virtio/virtio_pci.c
+++ b/drivers/net/virtio/virtio_pci.c
@@ -697,7 +697,7 @@ vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
 	if (virtio_read_caps(dev, hw) == 0) {
 		PMD_INIT_LOG(INFO, "modern virtio pci detected.");
 		virtio_hw_internal[hw->port_id].vtpci_ops = &modern_ops;
-		hw->modern = 1;
+		hw->bus_type = VIRTIO_BUS_PCI_MODERN;
 		return 0;
 	}
 
@@ -716,7 +716,7 @@ vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
 	}
 
 	virtio_hw_internal[hw->port_id].vtpci_ops = &legacy_ops;
-	hw->modern   = 0;
+	hw->bus_type = VIRTIO_BUS_PCI_LEGACY;
 
 	return 0;
 }
diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
index ab61e911b8..6388f0a74d 100644
--- a/drivers/net/virtio/virtio_pci.h
+++ b/drivers/net/virtio/virtio_pci.h
@@ -243,7 +243,15 @@ struct virtio_pci_ops {
 
 struct virtio_net_config;
 
+enum virtio_bus_type {
+	VIRTIO_BUS_UNKNOWN,
+	VIRTIO_BUS_PCI_LEGACY,
+	VIRTIO_BUS_PCI_MODERN,
+	VIRTIO_BUS_USER,
+};
+
 struct virtio_hw {
+	enum virtio_bus_type bus_type;
 	struct virtnet_ctl *cvq;
 	uint64_t    req_guest_features;
 	uint64_t    guest_features;
@@ -253,7 +261,6 @@ struct virtio_hw {
 	uint16_t    vtnet_hdr_size;
 	uint8_t	    vlan_strip;
 	uint8_t	    use_msix;
-	uint8_t     modern;
 	uint8_t     use_vec_rx;
 	uint8_t     use_vec_tx;
 	uint8_t     use_inorder_rx;
diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
index 7abba1f1ee..441721b6ca 100644
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -629,7 +629,7 @@ virtio_user_eth_dev_alloc(struct rte_vdev_device *vdev)
 	 * Here just pretend that we support msix.
 	 */
 	hw->use_msix = 1;
-	hw->modern   = 0;
+	hw->bus_type = VIRTIO_BUS_USER;
 	hw->use_vec_rx = 0;
 	hw->use_vec_tx = 0;
 	hw->use_inorder_rx = 0;
-- 
2.29.2