net/nfp: fix packet/data length conversion

Chained mbufs hold data_len as the length of that particular mbuf
and pkt_len as the full packet length including all the chained
mbufs. It is not clear from the mbuf definition if pkt_len should
be set for all the mbufs in a chain, but code there for handling
mbufs suggests just the first mbuf requires to have pkt_len set.

NFP PMD was assuming pkt_len is set in all the chained mbufs and
unit tests for gather dma were building mbufs with pkt_len always
set. This patch gets rid of that assumption.

Fixes: b812daadad0d ("nfp: add Rx and Tx")
Cc: stable@dpdk.org
Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>

diff --git a/drivers/net/nfp/nfp_net.c b/drivers/net/nfp/nfp_net.c
index 9d9420d..6155d7c 100644 (file)
--- a/drivers/net/nfp/nfp_net.c
+++ b/drivers/net/nfp/nfp_net.c
@@ -2097,6 +2097,7 @@ nfp_net_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
                 * Checksum and VLAN flags just in the first descriptor for a
                 * multisegment packet, but TSO info needs to be in all of them.
                 */
+               txd.data_len = pkt->pkt_len;
                nfp_net_tx_tso(txq, &txd, pkt);
                nfp_net_tx_cksum(txq, &txd, pkt);
 
@@ -2132,7 +2133,7 @@ nfp_net_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 
                        /* Filling descriptors fields */
                        txds->dma_len = dma_size;
-                       txds->data_len = pkt->pkt_len;
+                       txds->data_len = txd.data_len;
                        txds->dma_addr_hi = (dma_addr >> 32) & 0xff;
                        txds->dma_addr_lo = (dma_addr & 0xffffffff);
                        ASSERT(free_descs > 0);