[dpdk-dev] [PATCH v3 07/10] vmxnet3: support jumbo frames

[Stephen Hemminger <stephen@networkplumber.org>]

From: Stephen Hemminger <shemming@brocade.com>

Add support for linking multi-segment buffers together to
handle Jumbo packets.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c |  3 +-
 lib/librte_pmd_vmxnet3/vmxnet3_ring.h   |  2 +
 lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c   | 76 ++++++++++++++++++++-------------
 3 files changed, 50 insertions(+), 31 deletions(-)

diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c b/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
index 35bb561..4f1bc4f 100644
--- a/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
+++ b/lib/librte_pmd_vmxnet3/vmxnet3_ethdev.c
@@ -401,6 +401,7 @@ vmxnet3_setup_driver_shared(struct rte_eth_dev *dev)
 {
 	struct rte_eth_conf port_conf = dev->data->dev_conf;
 	struct vmxnet3_hw *hw = dev->data->dev_private;
+	uint32_t mtu = dev->data->mtu;
 	Vmxnet3_DriverShared *shared = hw->shared;
 	Vmxnet3_DSDevRead *devRead = &shared->devRead;
 	uint32_t *mac_ptr;
@@ -418,7 +419,7 @@ vmxnet3_setup_driver_shared(struct rte_eth_dev *dev)
 	devRead->misc.driverInfo.vmxnet3RevSpt = 1;
 	devRead->misc.driverInfo.uptVerSpt     = 1;
 
-	devRead->misc.mtu = rte_le_to_cpu_32(dev->data->mtu);
+	devRead->misc.mtu = rte_le_to_cpu_32(mtu);
 	devRead->misc.queueDescPA  = hw->queueDescPA;
 	devRead->misc.queueDescLen = hw->queue_desc_len;
 	devRead->misc.numTxQueues  = hw->num_tx_queues;
diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_ring.h b/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
index 612487e..55ceadf 100644
--- a/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
+++ b/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
@@ -171,6 +171,8 @@ typedef struct vmxnet3_rx_queue {
 	uint32_t                    qid1;
 	uint32_t                    qid2;
 	Vmxnet3_RxQueueDesc         *shared;
+	struct rte_mbuf		    *start_seg;
+	struct rte_mbuf		    *last_seg;
 	struct vmxnet3_rxq_stats    stats;
 	bool                        stopped;
 	uint16_t                    queue_id;      /**< Device RX queue index. */
diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c b/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
index ba48a12..5cf187a 100644
--- a/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
+++ b/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
@@ -571,7 +571,6 @@ vmxnet3_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 	vmxnet3_rx_queue_t *rxq;
 	Vmxnet3_RxCompDesc *rcd;
 	vmxnet3_buf_info_t *rbi;
-	Vmxnet3_RxDesc *rxd;
 	struct rte_mbuf *rxm = NULL;
 	struct vmxnet3_hw *hw;
 
@@ -596,42 +595,18 @@ vmxnet3_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 
 		idx = rcd->rxdIdx;
 		ring_idx = (uint8_t)((rcd->rqID == rxq->qid1) ? 0 : 1);
-		rxd = (Vmxnet3_RxDesc *)rxq->cmd_ring[ring_idx].base + idx;
 		rbi = rxq->cmd_ring[ring_idx].buf_info + idx;
 
-		if (unlikely(rcd->sop != 1 || rcd->eop != 1)) {
-			rte_pktmbuf_free_seg(rbi->m);
-			PMD_RX_LOG(DEBUG, "Packet spread across multiple buffers\n)");
-			goto rcd_done;
-		}
 
 		PMD_RX_LOG(DEBUG, "rxd idx: %d ring idx: %d.", idx, ring_idx);
 
 #ifdef RTE_LIBRTE_VMXNET3_DEBUG_DRIVER
+		Vmxnet3_RxDesc *rxd
+			= (Vmxnet3_RxDesc *)rxq->cmd_ring[ring_idx].base + idx;
 		VMXNET3_ASSERT(rcd->len <= rxd->len);
 		VMXNET3_ASSERT(rbi->m);
 #endif
-		if (unlikely(rcd->len == 0)) {
-			PMD_RX_LOG(DEBUG, "Rx buf was skipped. rxring[%d][%d]\n)",
-				   ring_idx, idx);
-#ifdef RTE_LIBRTE_VMXNET3_DEBUG_DRIVER
-			VMXNET3_ASSERT(rcd->sop && rcd->eop);
-#endif
-			rte_pktmbuf_free_seg(rbi->m);
-			goto rcd_done;
-		}
 
-		/* Assuming a packet is coming in a single packet buffer */
-		if (unlikely(rxd->btype != VMXNET3_RXD_BTYPE_HEAD)) {
-			PMD_RX_LOG(DEBUG,
-				   "Alert : Misbehaving device, incorrect "
-				   " buffer type used. iPacket dropped.");
-			rte_pktmbuf_free_seg(rbi->m);
-			goto rcd_done;
-		}
-#ifdef RTE_LIBRTE_VMXNET3_DEBUG_DRIVER
-		VMXNET3_ASSERT(rxd->btype == VMXNET3_RXD_BTYPE_HEAD);
-#endif
 		/* Get the packet buffer pointer from buf_info */
 		rxm = rbi->m;
 
@@ -643,7 +618,7 @@ vmxnet3_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 		rxq->cmd_ring[ring_idx].next2comp = idx;
 
 		/* For RCD with EOP set, check if there is frame error */
-		if (unlikely(rcd->err)) {
+		if (unlikely(rcd->eop && rcd->err)) {
 			rxq->stats.drop_total++;
 			rxq->stats.drop_err++;
 
@@ -669,9 +644,49 @@ vmxnet3_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 		rxm->ol_flags = 0;
 		rxm->vlan_tci = 0;
 
-		vmxnet3_rx_offload(rcd, rxm);
+		/*
+		 * If this is the first buffer of the received packet,
+		 * set the pointer to the first mbuf of the packet
+		 * Otherwise, update the total length and the number of segments
+		 * of the current scattered packet, and update the pointer to
+		 * the last mbuf of the current packet.
+		 */
+		if (rcd->sop) {
+#ifdef RTE_LIBRTE_VMXNET3_DEBUG_DRIVER
+			VMXNET3_ASSERT(!rxq->start_seg);
+			VMXNET3_ASSERT(rxd->btype == VMXNET3_RXD_BTYPE_HEAD);
+#endif
+
+			if (unlikely(rcd->len == 0)) {
+				PMD_RX_LOG(DEBUG,
+					   "Rx buf was skipped. rxring[%d][%d])",
+					   ring_idx, idx);
+				rte_pktmbuf_free_seg(rbi->m);
+				goto rcd_done;
+			}
+
+			rxq->start_seg = rxm;
+			vmxnet3_rx_offload(rcd, rxm);
+		} else {
+			struct rte_mbuf *start = rxq->start_seg;
+
+#ifdef RTE_LIBRTE_VMXNET3_DEBUG_DRIVER
+			VMXNET3_ASSERT(rxd->btype == VMXNET3_RXD_BTYPE_BODY);
+			VMXNET3_ASSERT(start != NULL);
+#endif
+
+			start->pkt_len += rxm->data_len;
+			start->nb_segs++;
+
+			rxq->last_seg->next = rxm;
+		}
+		rxq->last_seg = rxm;
+
+		if (rcd->eop) {
+			rx_pkts[nb_rx++] = rxq->start_seg;
+			rxq->start_seg = NULL;
+		}
 
-		rx_pkts[nb_rx++] = rxm;
 rcd_done:
 		rxq->cmd_ring[ring_idx].next2comp = idx;
 		VMXNET3_INC_RING_IDX_ONLY(rxq->cmd_ring[ring_idx].next2comp, rxq->cmd_ring[ring_idx].size);
@@ -975,6 +990,7 @@ vmxnet3_dev_rxtx_init(struct rte_eth_dev *dev)
 			}
 		}
 		rxq->stopped = FALSE;
+		rxq->start_seg = NULL;
 	}
 
 	for (i = 0; i < dev->data->nb_tx_queues; i++) {
-- 
2.1.4