Imported Upstream version 16.07-rc1

Change-Id: I40a523e52f12e8496fdd69e902824b0226c303de
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

1 files changed, 547 insertions, 0 deletions

diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
new file mode 100644
index 00000000..5ac1d69c
--- /dev/null
+++ b/drivers/net/enic/enic_rxtx.c
@@ -0,0 +1,547 @@
+/* Copyright 2008-2016 Cisco Systems, Inc.  All rights reserved.
+ * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
+ *
+ * Copyright (c) 2014, Cisco Systems, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <rte_mbuf.h>
+#include <rte_ethdev.h>
+#include <rte_prefetch.h>
+
+#include "enic_compat.h"
+#include "rq_enet_desc.h"
+#include "enic.h"
+
+#define RTE_PMD_USE_PREFETCH
+
+#ifdef RTE_PMD_USE_PREFETCH
+/*Prefetch a cache line into all cache levels. */
+#define rte_enic_prefetch(p) rte_prefetch0(p)
+#else
+#define rte_enic_prefetch(p) do {} while (0)
+#endif
+
+#ifdef RTE_PMD_PACKET_PREFETCH
+#define rte_packet_prefetch(p) rte_prefetch1(p)
+#else
+#define rte_packet_prefetch(p) do {} while (0)
+#endif
+
+static inline uint16_t
+enic_cq_rx_desc_ciflags(struct cq_enet_rq_desc *crd)
+{
+	return le16_to_cpu(crd->completed_index_flags) & ~CQ_DESC_COMP_NDX_MASK;
+}
+
+static inline uint16_t
+enic_cq_rx_desc_bwflags(struct cq_enet_rq_desc *crd)
+{
+	return le16_to_cpu(crd->bytes_written_flags) &
+			   ~CQ_ENET_RQ_DESC_BYTES_WRITTEN_MASK;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_packet_error(uint16_t bwflags)
+{
+	return (bwflags & CQ_ENET_RQ_DESC_FLAGS_TRUNCATED) ==
+		CQ_ENET_RQ_DESC_FLAGS_TRUNCATED;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_eop(uint16_t ciflags)
+{
+	return (ciflags & CQ_ENET_RQ_DESC_FLAGS_EOP)
+		== CQ_ENET_RQ_DESC_FLAGS_EOP;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_csum_not_calc(struct cq_enet_rq_desc *cqrd)
+{
+	return (le16_to_cpu(cqrd->q_number_rss_type_flags) &
+		CQ_ENET_RQ_DESC_FLAGS_CSUM_NOT_CALC) ==
+		CQ_ENET_RQ_DESC_FLAGS_CSUM_NOT_CALC;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_ipv4_csum_ok(struct cq_enet_rq_desc *cqrd)
+{
+	return (cqrd->flags & CQ_ENET_RQ_DESC_FLAGS_IPV4_CSUM_OK) ==
+		CQ_ENET_RQ_DESC_FLAGS_IPV4_CSUM_OK;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_tcp_udp_csum_ok(struct cq_enet_rq_desc *cqrd)
+{
+	return (cqrd->flags & CQ_ENET_RQ_DESC_FLAGS_TCP_UDP_CSUM_OK) ==
+		CQ_ENET_RQ_DESC_FLAGS_TCP_UDP_CSUM_OK;
+}
+
+static inline uint8_t
+enic_cq_rx_desc_rss_type(struct cq_enet_rq_desc *cqrd)
+{
+	return (uint8_t)((le16_to_cpu(cqrd->q_number_rss_type_flags) >>
+		CQ_DESC_Q_NUM_BITS) & CQ_ENET_RQ_DESC_RSS_TYPE_MASK);
+}
+
+static inline uint32_t
+enic_cq_rx_desc_rss_hash(struct cq_enet_rq_desc *cqrd)
+{
+	return le32_to_cpu(cqrd->rss_hash);
+}
+
+static inline uint16_t
+enic_cq_rx_desc_vlan(struct cq_enet_rq_desc *cqrd)
+{
+	return le16_to_cpu(cqrd->vlan);
+}
+
+static inline uint16_t
+enic_cq_rx_desc_n_bytes(struct cq_desc *cqd)
+{
+	struct cq_enet_rq_desc *cqrd = (struct cq_enet_rq_desc *)cqd;
+	return le16_to_cpu(cqrd->bytes_written_flags) &
+		CQ_ENET_RQ_DESC_BYTES_WRITTEN_MASK;
+}
+
+static inline uint8_t
+enic_cq_rx_check_err(struct cq_desc *cqd)
+{
+	struct cq_enet_rq_desc *cqrd = (struct cq_enet_rq_desc *)cqd;
+	uint16_t bwflags;
+
+	bwflags = enic_cq_rx_desc_bwflags(cqrd);
+	if (unlikely(enic_cq_rx_desc_packet_error(bwflags)))
+		return 1;
+	return 0;
+}
+
+/* Lookup table to translate RX CQ flags to mbuf flags. */
+static inline uint32_t
+enic_cq_rx_flags_to_pkt_type(struct cq_desc *cqd)
+{
+	struct cq_enet_rq_desc *cqrd = (struct cq_enet_rq_desc *)cqd;
+	uint8_t cqrd_flags = cqrd->flags;
+	static const uint32_t cq_type_table[128] __rte_cache_aligned = {
+		[0x00] = RTE_PTYPE_UNKNOWN,
+		[0x20] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_NONFRAG,
+		[0x22] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_UDP,
+		[0x24] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_TCP,
+		[0x60] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_FRAG,
+		[0x62] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_UDP,
+		[0x64] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_TCP,
+		[0x10] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_NONFRAG,
+		[0x12] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_UDP,
+		[0x14] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_TCP,
+		[0x50] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_FRAG,
+		[0x52] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_UDP,
+		[0x54] = RTE_PTYPE_L2_ETHER | RTE_PTYPE_L3_IPV6_EXT_UNKNOWN
+			  | RTE_PTYPE_L4_TCP,
+		/* All others reserved */
+	};
+	cqrd_flags &= CQ_ENET_RQ_DESC_FLAGS_IPV4_FRAGMENT
+		| CQ_ENET_RQ_DESC_FLAGS_IPV4 | CQ_ENET_RQ_DESC_FLAGS_IPV6
+		| CQ_ENET_RQ_DESC_FLAGS_TCP | CQ_ENET_RQ_DESC_FLAGS_UDP;
+	return cq_type_table[cqrd_flags];
+}
+
+static inline void
+enic_cq_rx_to_pkt_flags(struct cq_desc *cqd, struct rte_mbuf *mbuf)
+{
+	struct cq_enet_rq_desc *cqrd = (struct cq_enet_rq_desc *)cqd;
+	uint16_t ciflags, bwflags, pkt_flags = 0;
+	ciflags = enic_cq_rx_desc_ciflags(cqrd);
+	bwflags = enic_cq_rx_desc_bwflags(cqrd);
+
+	mbuf->ol_flags = 0;
+
+	/* flags are meaningless if !EOP */
+	if (unlikely(!enic_cq_rx_desc_eop(ciflags)))
+		goto mbuf_flags_done;
+
+	/* VLAN stripping */
+	if (bwflags & CQ_ENET_RQ_DESC_FLAGS_VLAN_STRIPPED) {
+		pkt_flags |= PKT_RX_VLAN_PKT | PKT_RX_VLAN_STRIPPED;
+		mbuf->vlan_tci = enic_cq_rx_desc_vlan(cqrd);
+	} else {
+		mbuf->vlan_tci = 0;
+	}
+
+	/* RSS flag */
+	if (enic_cq_rx_desc_rss_type(cqrd)) {
+		pkt_flags |= PKT_RX_RSS_HASH;
+		mbuf->hash.rss = enic_cq_rx_desc_rss_hash(cqrd);
+	}
+
+	/* checksum flags */
+	if (!enic_cq_rx_desc_csum_not_calc(cqrd) &&
+		(mbuf->packet_type & RTE_PTYPE_L3_IPV4)) {
+		if (unlikely(!enic_cq_rx_desc_ipv4_csum_ok(cqrd)))
+			pkt_flags |= PKT_RX_IP_CKSUM_BAD;
+		if (mbuf->packet_type & (RTE_PTYPE_L4_UDP | RTE_PTYPE_L4_TCP)) {
+			if (unlikely(!enic_cq_rx_desc_tcp_udp_csum_ok(cqrd)))
+				pkt_flags |= PKT_RX_L4_CKSUM_BAD;
+		}
+	}
+
+ mbuf_flags_done:
+	mbuf->ol_flags = pkt_flags;
+}
+
+uint16_t
+enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
+	       uint16_t nb_pkts)
+{
+	struct vnic_rq *sop_rq = rx_queue;
+	struct vnic_rq *data_rq;
+	struct vnic_rq *rq;
+	struct enic *enic = vnic_dev_priv(sop_rq->vdev);
+	uint16_t cq_idx;
+	uint16_t rq_idx;
+	uint16_t rq_num;
+	struct rte_mbuf *nmb, *rxmb;
+	uint16_t nb_rx = 0;
+	struct vnic_cq *cq;
+	volatile struct cq_desc *cqd_ptr;
+	uint8_t color;
+	uint16_t seg_length;
+	struct rte_mbuf *first_seg = sop_rq->pkt_first_seg;
+	struct rte_mbuf *last_seg = sop_rq->pkt_last_seg;
+
+	cq = &enic->cq[enic_cq_rq(enic, sop_rq->index)];
+	cq_idx = cq->to_clean;		/* index of cqd, rqd, mbuf_table */
+	cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
+
+	data_rq = &enic->rq[sop_rq->data_queue_idx];
+
+	while (nb_rx < nb_pkts) {
+		volatile struct rq_enet_desc *rqd_ptr;
+		dma_addr_t dma_addr;
+		struct cq_desc cqd;
+		uint8_t packet_error;
+		uint16_t ciflags;
+
+		/* Check for pkts available */
+		color = (cqd_ptr->type_color >> CQ_DESC_COLOR_SHIFT)
+			& CQ_DESC_COLOR_MASK;
+		if (color == cq->last_color)
+			break;
+
+		/* Get the cq descriptor and extract rq info from it */
+		cqd = *cqd_ptr;
+		rq_num = cqd.q_number & CQ_DESC_Q_NUM_MASK;
+		rq_idx = cqd.completed_index & CQ_DESC_COMP_NDX_MASK;
+
+		rq = &enic->rq[rq_num];
+		rqd_ptr = ((struct rq_enet_desc *)rq->ring.descs) + rq_idx;
+
+		/* allocate a new mbuf */
+		nmb = rte_mbuf_raw_alloc(rq->mp);
+		if (nmb == NULL) {
+			rte_atomic64_inc(&enic->soft_stats.rx_nombuf);
+			break;
+		}
+
+		/* A packet error means descriptor and data are untrusted */
+		packet_error = enic_cq_rx_check_err(&cqd);
+
+		/* Get the mbuf to return and replace with one just allocated */
+		rxmb = rq->mbuf_ring[rq_idx];
+		rq->mbuf_ring[rq_idx] = nmb;
+
+		/* Increment cqd, rqd, mbuf_table index */
+		cq_idx++;
+		if (unlikely(cq_idx == cq->ring.desc_count)) {
+			cq_idx = 0;
+			cq->last_color = cq->last_color ? 0 : 1;
+		}
+
+		/* Prefetch next mbuf & desc while processing current one */
+		cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
+		rte_enic_prefetch(cqd_ptr);
+
+		ciflags = enic_cq_rx_desc_ciflags(
+			(struct cq_enet_rq_desc *)&cqd);
+
+		/* Push descriptor for newly allocated mbuf */
+		dma_addr = (dma_addr_t)(nmb->buf_physaddr +
+					RTE_PKTMBUF_HEADROOM);
+		rq_enet_desc_enc(rqd_ptr, dma_addr,
+				(rq->is_sop ? RQ_ENET_TYPE_ONLY_SOP
+				: RQ_ENET_TYPE_NOT_SOP),
+				nmb->buf_len - RTE_PKTMBUF_HEADROOM);
+
+		/* Fill in the rest of the mbuf */
+		seg_length = enic_cq_rx_desc_n_bytes(&cqd);
+
+		if (rq->is_sop) {
+			first_seg = rxmb;
+			first_seg->nb_segs = 1;
+			first_seg->pkt_len = seg_length;
+		} else {
+			first_seg->pkt_len = (uint16_t)(first_seg->pkt_len
+							+ seg_length);
+			first_seg->nb_segs++;
+			last_seg->next = rxmb;
+		}
+
+		rxmb->next = NULL;
+		rxmb->port = enic->port_id;
+		rxmb->data_len = seg_length;
+
+		rq->rx_nb_hold++;
+
+		if (!(enic_cq_rx_desc_eop(ciflags))) {
+			last_seg = rxmb;
+			continue;
+		}
+
+		/* cq rx flags are only valid if eop bit is set */
+		first_seg->packet_type = enic_cq_rx_flags_to_pkt_type(&cqd);
+		enic_cq_rx_to_pkt_flags(&cqd, first_seg);
+
+		if (unlikely(packet_error)) {
+			rte_pktmbuf_free(first_seg);
+			rte_atomic64_inc(&enic->soft_stats.rx_packet_errors);
+			continue;
+		}
+
+
+		/* prefetch mbuf data for caller */
+		rte_packet_prefetch(RTE_PTR_ADD(first_seg->buf_addr,
+				    RTE_PKTMBUF_HEADROOM));
+
+		/* store the mbuf address into the next entry of the array */
+		rx_pkts[nb_rx++] = first_seg;
+	}
+
+	sop_rq->pkt_first_seg = first_seg;
+	sop_rq->pkt_last_seg = last_seg;
+
+	cq->to_clean = cq_idx;
+
+	if ((sop_rq->rx_nb_hold + data_rq->rx_nb_hold) >
+	    sop_rq->rx_free_thresh) {
+		if (data_rq->in_use) {
+			data_rq->posted_index =
+				enic_ring_add(data_rq->ring.desc_count,
+					      data_rq->posted_index,
+					      data_rq->rx_nb_hold);
+			data_rq->rx_nb_hold = 0;
+		}
+		sop_rq->posted_index = enic_ring_add(sop_rq->ring.desc_count,
+						     sop_rq->posted_index,
+						     sop_rq->rx_nb_hold);
+		sop_rq->rx_nb_hold = 0;
+
+		rte_mb();
+		if (data_rq->in_use)
+			iowrite32(data_rq->posted_index,
+				  &data_rq->ctrl->posted_index);
+		rte_compiler_barrier();
+		iowrite32(sop_rq->posted_index, &sop_rq->ctrl->posted_index);
+	}
+
+
+	return nb_rx;
+}
+
+static inline void enic_free_wq_bufs(struct vnic_wq *wq, u16 completed_index)
+{
+	struct vnic_wq_buf *buf;
+	struct rte_mbuf *m, *free[ENIC_MAX_WQ_DESCS];
+	unsigned int nb_to_free, nb_free = 0, i;
+	struct rte_mempool *pool;
+	unsigned int tail_idx;
+	unsigned int desc_count = wq->ring.desc_count;
+
+	nb_to_free = enic_ring_sub(desc_count, wq->tail_idx, completed_index)
+				   + 1;
+	tail_idx = wq->tail_idx;
+	buf = &wq->bufs[tail_idx];
+	pool = ((struct rte_mbuf *)buf->mb)->pool;
+	for (i = 0; i < nb_to_free; i++) {
+		buf = &wq->bufs[tail_idx];
+		m = (struct rte_mbuf *)(buf->mb);
+		if (likely(m->pool == pool)) {
+			ENIC_ASSERT(nb_free < ENIC_MAX_WQ_DESCS);
+			free[nb_free++] = m;
+		} else {
+			rte_mempool_put_bulk(pool, (void *)free, nb_free);
+			free[0] = m;
+			nb_free = 1;
+			pool = m->pool;
+		}
+		tail_idx = enic_ring_incr(desc_count, tail_idx);
+		buf->mb = NULL;
+	}
+
+	rte_mempool_put_bulk(pool, (void **)free, nb_free);
+
+	wq->tail_idx = tail_idx;
+	wq->ring.desc_avail += nb_to_free;
+}
+
+unsigned int enic_cleanup_wq(__rte_unused struct enic *enic, struct vnic_wq *wq)
+{
+	u16 completed_index;
+
+	completed_index = *((uint32_t *)wq->cqmsg_rz->addr) & 0xffff;
+
+	if (wq->last_completed_index != completed_index) {
+		enic_free_wq_bufs(wq, completed_index);
+		wq->last_completed_index = completed_index;
+	}
+	return 0;
+}
+
+uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
+	uint16_t nb_pkts)
+{
+	uint16_t index;
+	unsigned int pkt_len, data_len;
+	unsigned int nb_segs;
+	struct rte_mbuf *tx_pkt;
+	struct vnic_wq *wq = (struct vnic_wq *)tx_queue;
+	struct enic *enic = vnic_dev_priv(wq->vdev);
+	unsigned short vlan_id;
+	uint64_t ol_flags;
+	uint64_t ol_flags_mask;
+	unsigned int wq_desc_avail;
+	int head_idx;
+	struct vnic_wq_buf *buf;
+	unsigned int desc_count;
+	struct wq_enet_desc *descs, *desc_p, desc_tmp;
+	uint16_t mss;
+	uint8_t vlan_tag_insert;
+	uint8_t eop;
+	uint64_t bus_addr;
+
+	enic_cleanup_wq(enic, wq);
+	wq_desc_avail = vnic_wq_desc_avail(wq);
+	head_idx = wq->head_idx;
+	desc_count = wq->ring.desc_count;
+	ol_flags_mask = PKT_TX_VLAN_PKT | PKT_TX_IP_CKSUM | PKT_TX_L4_MASK;
+
+	nb_pkts = RTE_MIN(nb_pkts, ENIC_TX_XMIT_MAX);
+
+	for (index = 0; index < nb_pkts; index++) {
+		tx_pkt = *tx_pkts++;
+		nb_segs = tx_pkt->nb_segs;
+		if (nb_segs > wq_desc_avail) {
+			if (index > 0)
+				goto post;
+			goto done;
+		}
+
+		pkt_len = tx_pkt->pkt_len;
+		data_len = tx_pkt->data_len;
+		ol_flags = tx_pkt->ol_flags;
+		mss = 0;
+		vlan_id = 0;
+		vlan_tag_insert = 0;
+		bus_addr = (dma_addr_t)
+			   (tx_pkt->buf_physaddr + tx_pkt->data_off);
+
+		descs = (struct wq_enet_desc *)wq->ring.descs;
+		desc_p = descs + head_idx;
+
+		eop = (data_len == pkt_len);
+
+		if (ol_flags & ol_flags_mask) {
+			if (ol_flags & PKT_TX_VLAN_PKT) {
+				vlan_tag_insert = 1;
+				vlan_id = tx_pkt->vlan_tci;
+			}
+
+			if (ol_flags & PKT_TX_IP_CKSUM)
+				mss |= ENIC_CALC_IP_CKSUM;
+
+			/* Nic uses just 1 bit for UDP and TCP */
+			switch (ol_flags & PKT_TX_L4_MASK) {
+			case PKT_TX_TCP_CKSUM:
+			case PKT_TX_UDP_CKSUM:
+				mss |= ENIC_CALC_TCP_UDP_CKSUM;
+				break;
+			}
+		}
+
+		wq_enet_desc_enc(&desc_tmp, bus_addr, data_len, mss, 0, 0, eop,
+				 eop, 0, vlan_tag_insert, vlan_id, 0);
+
+		*desc_p = desc_tmp;
+		buf = &wq->bufs[head_idx];
+		buf->mb = (void *)tx_pkt;
+		head_idx = enic_ring_incr(desc_count, head_idx);
+		wq_desc_avail--;
+
+		if (!eop) {
+			for (tx_pkt = tx_pkt->next; tx_pkt; tx_pkt =
+			    tx_pkt->next) {
+				data_len = tx_pkt->data_len;
+
+				if (tx_pkt->next == NULL)
+					eop = 1;
+				desc_p = descs + head_idx;
+				bus_addr = (dma_addr_t)(tx_pkt->buf_physaddr
+					   + tx_pkt->data_off);
+				wq_enet_desc_enc((struct wq_enet_desc *)
+						 &desc_tmp, bus_addr, data_len,
+						 mss, 0, 0, eop, eop, 0,
+						 vlan_tag_insert, vlan_id, 0);
+
+				*desc_p = desc_tmp;
+				buf = &wq->bufs[head_idx];
+				buf->mb = (void *)tx_pkt;
+				head_idx = enic_ring_incr(desc_count, head_idx);
+				wq_desc_avail--;
+			}
+		}
+	}
+ post:
+	rte_wmb();
+	iowrite32(head_idx, &wq->ctrl->posted_index);
+ done:
+	wq->ring.desc_avail = wq_desc_avail;
+	wq->head_idx = head_idx;
+
+	return index;
+}
+
+