[dpdk-dev] [PATCH v2 5/7] virtio: retrieve hdr_size from hw->vtnet_hdr_size

[Yuanhan Liu]

The mergeable virtio net hdr format has been the standard and the
only virtio net hdr format since virtio 1.0. Therefore, we could
not hardcode hdr_size to "sizeof(struct virtio_net_hdr)" any more
at virtio_recv_pkts(), otherwise, there would be a mismatch of
hdr size from rte_vhost_enqueue_burst() and virtio_recv_pkts(),
leading a packet corruption.

Instead, we should retrieve it from hw->vtnet_hdr_size; we will
do proper settings at eth_virtio_dev_init().

Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
---
 drivers/net/virtio/virtio_rxtx.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index b7267c0..41a1366 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -560,7 +560,7 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 	struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 	int error;
 	uint32_t i, nb_enqueued;
-	const uint32_t hdr_size = sizeof(struct virtio_net_hdr);
+	uint32_t hdr_size;
 
 	nb_used = VIRTQUEUE_NUSED(rxvq);
 
@@ -580,6 +580,7 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 	hw = rxvq->hw;
 	nb_rx = 0;
 	nb_enqueued = 0;
+	hdr_size = hw->vtnet_hdr_size;
 
 	for (i = 0; i < num ; i++) {
 		rxm = rcv_pkts[i];
@@ -664,7 +665,7 @@ virtio_recv_mergeable_pkts(void *rx_queue,
 	uint32_t seg_num;
 	uint16_t extra_idx;
 	uint32_t seg_res;
-	const uint32_t hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	uint32_t hdr_size;
 
 	nb_used = VIRTQUEUE_NUSED(rxvq);
 
@@ -682,6 +683,7 @@ virtio_recv_mergeable_pkts(void *rx_queue,
 	seg_num = 0;
 	extra_idx = 0;
 	seg_res = 0;
+	hdr_size = hw->vtnet_hdr_size;
 
 	while (i < nb_used) {
 		struct virtio_net_hdr_mrg_rxbuf *header;
-- 
1.9.0