[dpdk-dev] [PATCH v3 1/2] net/virtio: add Tx preparation

[Andrew Rybchenko <arybchenko@solarflare.com>]

From: Dilshod Urazov <Dilshod.Urazov@oktetlabs.ru>

Virtio requires pseudo-header checksum in TCP/UDP checksum to do
offload, but it was lost when Tx prepare is introduced. Also
rte_validate_tx_offload() should be used to validate Tx offloads.

Also it is incorrect to do virtio_tso_fix_cksum() after prepend
to mbuf without taking prepended size into account, since layer 2/3/4
lengths provide incorrect offsets after prepend.

Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")
Cc: stable@dpdk.org

Signed-off-by: Dilshod Urazov <Dilshod.Urazov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
---
v3:
  - add a patch to move soft VLAN insertion to Tx prepare

 drivers/net/virtio/virtio_ethdev.c |  1 +
 drivers/net/virtio/virtio_ethdev.h |  3 +++
 drivers/net/virtio/virtio_rxtx.c   | 32 +++++++++++++++++++++++++++++-
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index c4570bbf8..97d3c293e 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1473,6 +1473,7 @@ set_rxtx_funcs(struct rte_eth_dev *eth_dev)
 {
 	struct virtio_hw *hw = eth_dev->data->dev_private;
 
+	eth_dev->tx_pkt_prepare = virtio_xmit_pkts_prepare;
 	if (vtpci_packed_queue(hw)) {
 		PMD_INIT_LOG(INFO,
 			"virtio: using packed ring %s Tx path on port %u",
diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
index 45e96f32b..20d331795 100644
--- a/drivers/net/virtio/virtio_ethdev.h
+++ b/drivers/net/virtio/virtio_ethdev.h
@@ -89,6 +89,9 @@ uint16_t virtio_recv_mergeable_pkts_packed(void *rx_queue,
 uint16_t virtio_recv_pkts_inorder(void *rx_queue,
 		struct rte_mbuf **rx_pkts, uint16_t nb_pkts);
 
+uint16_t virtio_xmit_pkts_prepare(void *tx_queue, struct rte_mbuf **tx_pkts,
+		uint16_t nb_pkts);
+
 uint16_t virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 		uint16_t nb_pkts);
 uint16_t virtio_xmit_pkts_packed(void *tx_queue, struct rte_mbuf **tx_pkts,
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 1f1178467..07f8f47de 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -559,7 +559,6 @@ virtqueue_xmit_offload(struct virtio_net_hdr *hdr,
 
 		/* TCP Segmentation Offload */
 		if (cookie->ol_flags & PKT_TX_TCP_SEG) {
-			virtio_tso_fix_cksum(cookie);
 			hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
 				VIRTIO_NET_HDR_GSO_TCPV6 :
 				VIRTIO_NET_HDR_GSO_TCPV4;
@@ -1949,6 +1948,37 @@ virtio_recv_mergeable_pkts_packed(void *rx_queue,
 	return nb_rx;
 }
 
+uint16_t
+virtio_xmit_pkts_prepare(void *tx_queue __rte_unused, struct rte_mbuf **tx_pkts,
+			uint16_t nb_pkts)
+{
+	uint16_t nb_tx;
+	int error;
+
+	for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
+		struct rte_mbuf *m = tx_pkts[nb_tx];
+
+#ifdef RTE_LIBRTE_ETHDEV_DEBUG
+		error = rte_validate_tx_offload(m);
+		if (unlikely(error)) {
+			rte_errno = -error;
+			break;
+		}
+#endif
+
+		error = rte_net_intel_cksum_prepare(m);
+		if (unlikely(error)) {
+			rte_errno = -error;
+			break;
+		}
+
+		if (m->ol_flags & PKT_TX_TCP_SEG)
+			virtio_tso_fix_cksum(m);
+	}
+
+	return nb_tx;
+}
+
 uint16_t
 virtio_xmit_pkts_packed(void *tx_queue, struct rte_mbuf **tx_pkts,
 			uint16_t nb_pkts)
-- 
2.17.1