virtio: move to drivers/net/
[dpdk.git] / lib / librte_pmd_virtio / virtio_rxtx.c
diff --git a/lib/librte_pmd_virtio/virtio_rxtx.c b/lib/librte_pmd_virtio/virtio_rxtx.c
deleted file mode 100644 (file)
index 3ff275c..0000000
+++ /dev/null
@@ -1,815 +0,0 @@
-/*-
- *   BSD LICENSE
- *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- *   All rights reserved.
- *
- *   Redistribution and use in source and binary forms, with or without
- *   modification, are permitted provided that the following conditions
- *   are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * 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.
- *     * Neither the name of Intel Corporation nor the names of its
- *       contributors may be used to endorse or promote products derived
- *       from this software without specific prior written permission.
- *
- *   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
- *   OWNER 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 <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-
-#include <rte_cycles.h>
-#include <rte_memory.h>
-#include <rte_memzone.h>
-#include <rte_branch_prediction.h>
-#include <rte_mempool.h>
-#include <rte_malloc.h>
-#include <rte_mbuf.h>
-#include <rte_ether.h>
-#include <rte_ethdev.h>
-#include <rte_prefetch.h>
-#include <rte_string_fns.h>
-#include <rte_errno.h>
-#include <rte_byteorder.h>
-
-#include "virtio_logs.h"
-#include "virtio_ethdev.h"
-#include "virtqueue.h"
-
-#ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
-#define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
-#else
-#define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
-#endif
-
-static void
-vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
-{
-       struct vring_desc *dp, *dp_tail;
-       struct vq_desc_extra *dxp;
-       uint16_t desc_idx_last = desc_idx;
-
-       dp  = &vq->vq_ring.desc[desc_idx];
-       dxp = &vq->vq_descx[desc_idx];
-       vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
-       if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
-               while (dp->flags & VRING_DESC_F_NEXT) {
-                       desc_idx_last = dp->next;
-                       dp = &vq->vq_ring.desc[dp->next];
-               }
-       }
-       dxp->ndescs = 0;
-
-       /*
-        * We must append the existing free chain, if any, to the end of
-        * newly freed chain. If the virtqueue was completely used, then
-        * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
-        */
-       if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
-               vq->vq_desc_head_idx = desc_idx;
-       } else {
-               dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
-               dp_tail->next = desc_idx;
-       }
-
-       vq->vq_desc_tail_idx = desc_idx_last;
-       dp->next = VQ_RING_DESC_CHAIN_END;
-}
-
-static uint16_t
-virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
-                          uint32_t *len, uint16_t num)
-{
-       struct vring_used_elem *uep;
-       struct rte_mbuf *cookie;
-       uint16_t used_idx, desc_idx;
-       uint16_t i;
-
-       /*  Caller does the check */
-       for (i = 0; i < num ; i++) {
-               used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
-               uep = &vq->vq_ring.used->ring[used_idx];
-               desc_idx = (uint16_t) uep->id;
-               len[i] = uep->len;
-               cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
-
-               if (unlikely(cookie == NULL)) {
-                       PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
-                               vq->vq_used_cons_idx);
-                       break;
-               }
-
-               rte_prefetch0(cookie);
-               rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
-               rx_pkts[i]  = cookie;
-               vq->vq_used_cons_idx++;
-               vq_ring_free_chain(vq, desc_idx);
-               vq->vq_descx[desc_idx].cookie = NULL;
-       }
-
-       return i;
-}
-
-#ifndef DEFAULT_TX_FREE_THRESH
-#define DEFAULT_TX_FREE_THRESH 32
-#endif
-
-/* Cleanup from completed transmits. */
-static void
-virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
-{
-       uint16_t i, used_idx, desc_idx;
-       for (i = 0; i < num; i++) {
-               struct vring_used_elem *uep;
-               struct vq_desc_extra *dxp;
-
-               used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
-               uep = &vq->vq_ring.used->ring[used_idx];
-
-               desc_idx = (uint16_t) uep->id;
-               dxp = &vq->vq_descx[desc_idx];
-               vq->vq_used_cons_idx++;
-               vq_ring_free_chain(vq, desc_idx);
-
-               if (dxp->cookie != NULL) {
-                       rte_pktmbuf_free(dxp->cookie);
-                       dxp->cookie = NULL;
-               }
-       }
-}
-
-
-static inline int
-virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
-{
-       struct vq_desc_extra *dxp;
-       struct virtio_hw *hw = vq->hw;
-       struct vring_desc *start_dp;
-       uint16_t needed = 1;
-       uint16_t head_idx, idx;
-
-       if (unlikely(vq->vq_free_cnt == 0))
-               return -ENOSPC;
-       if (unlikely(vq->vq_free_cnt < needed))
-               return -EMSGSIZE;
-
-       head_idx = vq->vq_desc_head_idx;
-       if (unlikely(head_idx >= vq->vq_nentries))
-               return -EFAULT;
-
-       idx = head_idx;
-       dxp = &vq->vq_descx[idx];
-       dxp->cookie = (void *)cookie;
-       dxp->ndescs = needed;
-
-       start_dp = vq->vq_ring.desc;
-       start_dp[idx].addr =
-               (uint64_t)(cookie->buf_physaddr + RTE_PKTMBUF_HEADROOM
-               - hw->vtnet_hdr_size);
-       start_dp[idx].len =
-               cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
-       start_dp[idx].flags =  VRING_DESC_F_WRITE;
-       idx = start_dp[idx].next;
-       vq->vq_desc_head_idx = idx;
-       if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
-               vq->vq_desc_tail_idx = idx;
-       vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
-       vq_update_avail_ring(vq, head_idx);
-
-       return 0;
-}
-
-static int
-virtqueue_enqueue_xmit(struct virtqueue *txvq, struct rte_mbuf *cookie)
-{
-       struct vq_desc_extra *dxp;
-       struct vring_desc *start_dp;
-       uint16_t seg_num = cookie->nb_segs;
-       uint16_t needed = 1 + seg_num;
-       uint16_t head_idx, idx;
-       uint16_t head_size = txvq->hw->vtnet_hdr_size;
-
-       if (unlikely(txvq->vq_free_cnt == 0))
-               return -ENOSPC;
-       if (unlikely(txvq->vq_free_cnt < needed))
-               return -EMSGSIZE;
-       head_idx = txvq->vq_desc_head_idx;
-       if (unlikely(head_idx >= txvq->vq_nentries))
-               return -EFAULT;
-
-       idx = head_idx;
-       dxp = &txvq->vq_descx[idx];
-       dxp->cookie = (void *)cookie;
-       dxp->ndescs = needed;
-
-       start_dp = txvq->vq_ring.desc;
-       start_dp[idx].addr =
-               txvq->virtio_net_hdr_mem + idx * head_size;
-       start_dp[idx].len = (uint32_t)head_size;
-       start_dp[idx].flags = VRING_DESC_F_NEXT;
-
-       for (; ((seg_num > 0) && (cookie != NULL)); seg_num--) {
-               idx = start_dp[idx].next;
-               start_dp[idx].addr  = RTE_MBUF_DATA_DMA_ADDR(cookie);
-               start_dp[idx].len   = cookie->data_len;
-               start_dp[idx].flags = VRING_DESC_F_NEXT;
-               cookie = cookie->next;
-       }
-
-       start_dp[idx].flags &= ~VRING_DESC_F_NEXT;
-       idx = start_dp[idx].next;
-       txvq->vq_desc_head_idx = idx;
-       if (txvq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
-               txvq->vq_desc_tail_idx = idx;
-       txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
-       vq_update_avail_ring(txvq, head_idx);
-
-       return 0;
-}
-
-static inline struct rte_mbuf *
-rte_rxmbuf_alloc(struct rte_mempool *mp)
-{
-       struct rte_mbuf *m;
-
-       m = __rte_mbuf_raw_alloc(mp);
-       __rte_mbuf_sanity_check_raw(m, 0);
-
-       return m;
-}
-
-static void
-virtio_dev_vring_start(struct virtqueue *vq, int queue_type)
-{
-       struct rte_mbuf *m;
-       int i, nbufs, error, size = vq->vq_nentries;
-       struct vring *vr = &vq->vq_ring;
-       uint8_t *ring_mem = vq->vq_ring_virt_mem;
-
-       PMD_INIT_FUNC_TRACE();
-
-       /*
-        * Reinitialise since virtio port might have been stopped and restarted
-        */
-       memset(vq->vq_ring_virt_mem, 0, vq->vq_ring_size);
-       vring_init(vr, size, ring_mem, VIRTIO_PCI_VRING_ALIGN);
-       vq->vq_used_cons_idx = 0;
-       vq->vq_desc_head_idx = 0;
-       vq->vq_avail_idx = 0;
-       vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
-       vq->vq_free_cnt = vq->vq_nentries;
-       memset(vq->vq_descx, 0, sizeof(struct vq_desc_extra) * vq->vq_nentries);
-
-       /* Chain all the descriptors in the ring with an END */
-       for (i = 0; i < size - 1; i++)
-               vr->desc[i].next = (uint16_t)(i + 1);
-       vr->desc[i].next = VQ_RING_DESC_CHAIN_END;
-
-       /*
-        * Disable device(host) interrupting guest
-        */
-       virtqueue_disable_intr(vq);
-
-       /* Only rx virtqueue needs mbufs to be allocated at initialization */
-       if (queue_type == VTNET_RQ) {
-               if (vq->mpool == NULL)
-                       rte_exit(EXIT_FAILURE,
-                       "Cannot allocate initial mbufs for rx virtqueue");
-
-               /* Allocate blank mbufs for the each rx descriptor */
-               nbufs = 0;
-               error = ENOSPC;
-               while (!virtqueue_full(vq)) {
-                       m = rte_rxmbuf_alloc(vq->mpool);
-                       if (m == NULL)
-                               break;
-
-                       /******************************************
-                       *         Enqueue allocated buffers        *
-                       *******************************************/
-                       error = virtqueue_enqueue_recv_refill(vq, m);
-
-                       if (error) {
-                               rte_pktmbuf_free(m);
-                               break;
-                       }
-                       nbufs++;
-               }
-
-               vq_update_avail_idx(vq);
-
-               PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
-
-               VIRTIO_WRITE_REG_2(vq->hw, VIRTIO_PCI_QUEUE_SEL,
-                       vq->vq_queue_index);
-               VIRTIO_WRITE_REG_4(vq->hw, VIRTIO_PCI_QUEUE_PFN,
-                       vq->mz->phys_addr >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
-       } else if (queue_type == VTNET_TQ) {
-               VIRTIO_WRITE_REG_2(vq->hw, VIRTIO_PCI_QUEUE_SEL,
-                       vq->vq_queue_index);
-               VIRTIO_WRITE_REG_4(vq->hw, VIRTIO_PCI_QUEUE_PFN,
-                       vq->mz->phys_addr >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
-       } else {
-               VIRTIO_WRITE_REG_2(vq->hw, VIRTIO_PCI_QUEUE_SEL,
-                       vq->vq_queue_index);
-               VIRTIO_WRITE_REG_4(vq->hw, VIRTIO_PCI_QUEUE_PFN,
-                       vq->mz->phys_addr >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
-       }
-}
-
-void
-virtio_dev_cq_start(struct rte_eth_dev *dev)
-{
-       struct virtio_hw *hw = dev->data->dev_private;
-
-       if (hw->cvq) {
-               virtio_dev_vring_start(hw->cvq, VTNET_CQ);
-               VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq);
-       }
-}
-
-void
-virtio_dev_rxtx_start(struct rte_eth_dev *dev)
-{
-       /*
-        * Start receive and transmit vrings
-        * -    Setup vring structure for all queues
-        * -    Initialize descriptor for the rx vring
-        * -    Allocate blank mbufs for the each rx descriptor
-        *
-        */
-       int i;
-
-       PMD_INIT_FUNC_TRACE();
-
-       /* Start rx vring. */
-       for (i = 0; i < dev->data->nb_rx_queues; i++) {
-               virtio_dev_vring_start(dev->data->rx_queues[i], VTNET_RQ);
-               VIRTQUEUE_DUMP((struct virtqueue *)dev->data->rx_queues[i]);
-       }
-
-       /* Start tx vring. */
-       for (i = 0; i < dev->data->nb_tx_queues; i++) {
-               virtio_dev_vring_start(dev->data->tx_queues[i], VTNET_TQ);
-               VIRTQUEUE_DUMP((struct virtqueue *)dev->data->tx_queues[i]);
-       }
-}
-
-int
-virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
-                       uint16_t queue_idx,
-                       uint16_t nb_desc,
-                       unsigned int socket_id,
-                       __rte_unused const struct rte_eth_rxconf *rx_conf,
-                       struct rte_mempool *mp)
-{
-       uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
-       struct virtqueue *vq;
-       int ret;
-
-       PMD_INIT_FUNC_TRACE();
-       ret = virtio_dev_queue_setup(dev, VTNET_RQ, queue_idx, vtpci_queue_idx,
-                       nb_desc, socket_id, &vq);
-       if (ret < 0) {
-               PMD_INIT_LOG(ERR, "tvq initialization failed");
-               return ret;
-       }
-
-       /* Create mempool for rx mbuf allocation */
-       vq->mpool = mp;
-
-       dev->data->rx_queues[queue_idx] = vq;
-       return 0;
-}
-
-/*
- * struct rte_eth_dev *dev: Used to update dev
- * uint16_t nb_desc: Defaults to values read from config space
- * unsigned int socket_id: Used to allocate memzone
- * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
- * uint16_t queue_idx: Just used as an index in dev txq list
- */
-int
-virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
-                       uint16_t queue_idx,
-                       uint16_t nb_desc,
-                       unsigned int socket_id,
-                       const struct rte_eth_txconf *tx_conf)
-{
-       uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
-       struct virtqueue *vq;
-       uint16_t tx_free_thresh;
-       int ret;
-
-       PMD_INIT_FUNC_TRACE();
-
-       if ((tx_conf->txq_flags & ETH_TXQ_FLAGS_NOXSUMS)
-           != ETH_TXQ_FLAGS_NOXSUMS) {
-               PMD_INIT_LOG(ERR, "TX checksum offload not supported\n");
-               return -EINVAL;
-       }
-
-       ret = virtio_dev_queue_setup(dev, VTNET_TQ, queue_idx, vtpci_queue_idx,
-                       nb_desc, socket_id, &vq);
-       if (ret < 0) {
-               PMD_INIT_LOG(ERR, "rvq initialization failed");
-               return ret;
-       }
-
-       tx_free_thresh = tx_conf->tx_free_thresh;
-       if (tx_free_thresh == 0)
-               tx_free_thresh =
-                       RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
-
-       if (tx_free_thresh >= (vq->vq_nentries - 3)) {
-               RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
-                       "number of TX entries minus 3 (%u)."
-                       " (tx_free_thresh=%u port=%u queue=%u)\n",
-                       vq->vq_nentries - 3,
-                       tx_free_thresh, dev->data->port_id, queue_idx);
-               return -EINVAL;
-       }
-
-       vq->vq_free_thresh = tx_free_thresh;
-
-       dev->data->tx_queues[queue_idx] = vq;
-       return 0;
-}
-
-static void
-virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
-{
-       int error;
-       /*
-        * Requeue the discarded mbuf. This should always be
-        * successful since it was just dequeued.
-        */
-       error = virtqueue_enqueue_recv_refill(vq, m);
-       if (unlikely(error)) {
-               RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
-               rte_pktmbuf_free(m);
-       }
-}
-
-#define VIRTIO_MBUF_BURST_SZ 64
-#define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
-uint16_t
-virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
-{
-       struct virtqueue *rxvq = rx_queue;
-       struct virtio_hw *hw;
-       struct rte_mbuf *rxm, *new_mbuf;
-       uint16_t nb_used, num, nb_rx;
-       uint32_t len[VIRTIO_MBUF_BURST_SZ];
-       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);
-
-       nb_used = VIRTQUEUE_NUSED(rxvq);
-
-       virtio_rmb();
-
-       num = (uint16_t)(likely(nb_used <= nb_pkts) ? nb_used : nb_pkts);
-       num = (uint16_t)(likely(num <= VIRTIO_MBUF_BURST_SZ) ? num : VIRTIO_MBUF_BURST_SZ);
-       if (likely(num > DESC_PER_CACHELINE))
-               num = num - ((rxvq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
-
-       if (num == 0)
-               return 0;
-
-       num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, num);
-       PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
-
-       hw = rxvq->hw;
-       nb_rx = 0;
-       nb_enqueued = 0;
-
-       for (i = 0; i < num ; i++) {
-               rxm = rcv_pkts[i];
-
-               PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
-
-               if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
-                       PMD_RX_LOG(ERR, "Packet drop");
-                       nb_enqueued++;
-                       virtio_discard_rxbuf(rxvq, rxm);
-                       rxvq->errors++;
-                       continue;
-               }
-
-               rxm->port = rxvq->port_id;
-               rxm->data_off = RTE_PKTMBUF_HEADROOM;
-
-               rxm->nb_segs = 1;
-               rxm->next = NULL;
-               rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
-               rxm->data_len = (uint16_t)(len[i] - hdr_size);
-
-               if (hw->vlan_strip)
-                       rte_vlan_strip(rxm);
-
-               VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
-
-               rx_pkts[nb_rx++] = rxm;
-               rxvq->bytes += rx_pkts[nb_rx - 1]->pkt_len;
-       }
-
-       rxvq->packets += nb_rx;
-
-       /* Allocate new mbuf for the used descriptor */
-       error = ENOSPC;
-       while (likely(!virtqueue_full(rxvq))) {
-               new_mbuf = rte_rxmbuf_alloc(rxvq->mpool);
-               if (unlikely(new_mbuf == NULL)) {
-                       struct rte_eth_dev *dev
-                               = &rte_eth_devices[rxvq->port_id];
-                       dev->data->rx_mbuf_alloc_failed++;
-                       break;
-               }
-               error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
-               if (unlikely(error)) {
-                       rte_pktmbuf_free(new_mbuf);
-                       break;
-               }
-               nb_enqueued++;
-       }
-
-       if (likely(nb_enqueued)) {
-               vq_update_avail_idx(rxvq);
-
-               if (unlikely(virtqueue_kick_prepare(rxvq))) {
-                       virtqueue_notify(rxvq);
-                       PMD_RX_LOG(DEBUG, "Notified\n");
-               }
-       }
-
-       return nb_rx;
-}
-
-uint16_t
-virtio_recv_mergeable_pkts(void *rx_queue,
-                       struct rte_mbuf **rx_pkts,
-                       uint16_t nb_pkts)
-{
-       struct virtqueue *rxvq = rx_queue;
-       struct virtio_hw *hw;
-       struct rte_mbuf *rxm, *new_mbuf;
-       uint16_t nb_used, num, nb_rx;
-       uint32_t len[VIRTIO_MBUF_BURST_SZ];
-       struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
-       struct rte_mbuf *prev;
-       int error;
-       uint32_t i, nb_enqueued;
-       uint32_t seg_num;
-       uint16_t extra_idx;
-       uint32_t seg_res;
-       const uint32_t hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
-
-       nb_used = VIRTQUEUE_NUSED(rxvq);
-
-       virtio_rmb();
-
-       if (nb_used == 0)
-               return 0;
-
-       PMD_RX_LOG(DEBUG, "used:%d\n", nb_used);
-
-       hw = rxvq->hw;
-       nb_rx = 0;
-       i = 0;
-       nb_enqueued = 0;
-       seg_num = 0;
-       extra_idx = 0;
-       seg_res = 0;
-
-       while (i < nb_used) {
-               struct virtio_net_hdr_mrg_rxbuf *header;
-
-               if (nb_rx == nb_pkts)
-                       break;
-
-               num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, 1);
-               if (num != 1)
-                       continue;
-
-               i++;
-
-               PMD_RX_LOG(DEBUG, "dequeue:%d\n", num);
-               PMD_RX_LOG(DEBUG, "packet len:%d\n", len[0]);
-
-               rxm = rcv_pkts[0];
-
-               if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
-                       PMD_RX_LOG(ERR, "Packet drop\n");
-                       nb_enqueued++;
-                       virtio_discard_rxbuf(rxvq, rxm);
-                       rxvq->errors++;
-                       continue;
-               }
-
-               header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
-                       RTE_PKTMBUF_HEADROOM - hdr_size);
-               seg_num = header->num_buffers;
-
-               if (seg_num == 0)
-                       seg_num = 1;
-
-               rxm->data_off = RTE_PKTMBUF_HEADROOM;
-               rxm->nb_segs = seg_num;
-               rxm->next = NULL;
-               rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
-               rxm->data_len = (uint16_t)(len[0] - hdr_size);
-
-               rxm->port = rxvq->port_id;
-               rx_pkts[nb_rx] = rxm;
-               prev = rxm;
-
-               seg_res = seg_num - 1;
-
-               while (seg_res != 0) {
-                       /*
-                        * Get extra segments for current uncompleted packet.
-                        */
-                       uint16_t  rcv_cnt =
-                               RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
-                       if (likely(VIRTQUEUE_NUSED(rxvq) >= rcv_cnt)) {
-                               uint32_t rx_num =
-                                       virtqueue_dequeue_burst_rx(rxvq,
-                                       rcv_pkts, len, rcv_cnt);
-                               i += rx_num;
-                               rcv_cnt = rx_num;
-                       } else {
-                               PMD_RX_LOG(ERR,
-                                       "No enough segments for packet.\n");
-                               nb_enqueued++;
-                               virtio_discard_rxbuf(rxvq, rxm);
-                               rxvq->errors++;
-                               break;
-                       }
-
-                       extra_idx = 0;
-
-                       while (extra_idx < rcv_cnt) {
-                               rxm = rcv_pkts[extra_idx];
-
-                               rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
-                               rxm->next = NULL;
-                               rxm->pkt_len = (uint32_t)(len[extra_idx]);
-                               rxm->data_len = (uint16_t)(len[extra_idx]);
-
-                               if (prev)
-                                       prev->next = rxm;
-
-                               prev = rxm;
-                               rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
-                               extra_idx++;
-                       };
-                       seg_res -= rcv_cnt;
-               }
-
-               if (hw->vlan_strip)
-                       rte_vlan_strip(rx_pkts[nb_rx]);
-
-               VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
-                       rx_pkts[nb_rx]->data_len);
-
-               rxvq->bytes += rx_pkts[nb_rx]->pkt_len;
-               nb_rx++;
-       }
-
-       rxvq->packets += nb_rx;
-
-       /* Allocate new mbuf for the used descriptor */
-       error = ENOSPC;
-       while (likely(!virtqueue_full(rxvq))) {
-               new_mbuf = rte_rxmbuf_alloc(rxvq->mpool);
-               if (unlikely(new_mbuf == NULL)) {
-                       struct rte_eth_dev *dev
-                               = &rte_eth_devices[rxvq->port_id];
-                       dev->data->rx_mbuf_alloc_failed++;
-                       break;
-               }
-               error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
-               if (unlikely(error)) {
-                       rte_pktmbuf_free(new_mbuf);
-                       break;
-               }
-               nb_enqueued++;
-       }
-
-       if (likely(nb_enqueued)) {
-               vq_update_avail_idx(rxvq);
-
-               if (unlikely(virtqueue_kick_prepare(rxvq))) {
-                       virtqueue_notify(rxvq);
-                       PMD_RX_LOG(DEBUG, "Notified");
-               }
-       }
-
-       return nb_rx;
-}
-
-uint16_t
-virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
-{
-       struct virtqueue *txvq = tx_queue;
-       struct rte_mbuf *txm;
-       uint16_t nb_used, nb_tx;
-       int error;
-
-       if (unlikely(nb_pkts < 1))
-               return nb_pkts;
-
-       PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
-       nb_used = VIRTQUEUE_NUSED(txvq);
-
-       virtio_rmb();
-       if (likely(nb_used > txvq->vq_free_thresh))
-               virtio_xmit_cleanup(txvq, nb_used);
-
-       nb_tx = 0;
-
-       while (nb_tx < nb_pkts) {
-               /* Need one more descriptor for virtio header. */
-               int need = tx_pkts[nb_tx]->nb_segs - txvq->vq_free_cnt + 1;
-
-               /*Positive value indicates it need free vring descriptors */
-               if (unlikely(need > 0)) {
-                       nb_used = VIRTQUEUE_NUSED(txvq);
-                       virtio_rmb();
-                       need = RTE_MIN(need, (int)nb_used);
-
-                       virtio_xmit_cleanup(txvq, need);
-                       need = (int)tx_pkts[nb_tx]->nb_segs -
-                               txvq->vq_free_cnt + 1;
-               }
-
-               /*
-                * Zero or negative value indicates it has enough free
-                * descriptors to use for transmitting.
-                */
-               if (likely(need <= 0)) {
-                       txm = tx_pkts[nb_tx];
-
-                       /* Do VLAN tag insertion */
-                       if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
-                               error = rte_vlan_insert(&txm);
-                               if (unlikely(error)) {
-                                       rte_pktmbuf_free(txm);
-                                       ++nb_tx;
-                                       continue;
-                               }
-                       }
-
-                       /* Enqueue Packet buffers */
-                       error = virtqueue_enqueue_xmit(txvq, txm);
-                       if (unlikely(error)) {
-                               if (error == ENOSPC)
-                                       PMD_TX_LOG(ERR, "virtqueue_enqueue Free count = 0");
-                               else if (error == EMSGSIZE)
-                                       PMD_TX_LOG(ERR, "virtqueue_enqueue Free count < 1");
-                               else
-                                       PMD_TX_LOG(ERR, "virtqueue_enqueue error: %d", error);
-                               break;
-                       }
-                       nb_tx++;
-                       txvq->bytes += txm->pkt_len;
-               } else {
-                       PMD_TX_LOG(ERR, "No free tx descriptors to transmit");
-                       break;
-               }
-       }
-
-       txvq->packets += nb_tx;
-
-       if (likely(nb_tx)) {
-               vq_update_avail_idx(txvq);
-
-               if (unlikely(virtqueue_kick_prepare(txvq))) {
-                       virtqueue_notify(txvq);
-                       PMD_TX_LOG(DEBUG, "Notified backend after xmit");
-               }
-       }
-
-       return nb_tx;
-}