drivers/net/virtio/virtio_rxtx.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdint.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <errno.h>
  39
  40 #include <rte_cycles.h>
  41 #include <rte_memory.h>
  42 #include <rte_branch_prediction.h>
  43 #include <rte_mempool.h>
  44 #include <rte_malloc.h>
  45 #include <rte_mbuf.h>
  46 #include <rte_ether.h>
  47 #include <rte_ethdev.h>
  48 #include <rte_prefetch.h>
  49 #include <rte_string_fns.h>
  50 #include <rte_errno.h>
  51 #include <rte_byteorder.h>
  52 #include <rte_net.h>
  53 #include <rte_ip.h>
  54 #include <rte_udp.h>
  55 #include <rte_tcp.h>
  56
  57 #include "virtio_logs.h"
  58 #include "virtio_ethdev.h"
  59 #include "virtio_pci.h"
  60 #include "virtqueue.h"
  61 #include "virtio_rxtx.h"
  62
  63 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
  64 #define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
  65 #else
  66 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
  67 #endif
  68
  69
  70 #define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
  71         ETH_TXQ_FLAGS_NOOFFLOADS)
  72
  73 int
  74 virtio_dev_rx_queue_done(void *rxq, uint16_t offset)
  75 {
  76         struct virtnet_rx *rxvq = rxq;
  77         struct virtqueue *vq = rxvq->vq;
  78
  79         return VIRTQUEUE_NUSED(vq) >= offset;
  80 }
  81
  82 void
  83 vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
  84 {
  85         struct vring_desc *dp, *dp_tail;
  86         struct vq_desc_extra *dxp;
  87         uint16_t desc_idx_last = desc_idx;
  88
  89         dp  = &vq->vq_ring.desc[desc_idx];
  90         dxp = &vq->vq_descx[desc_idx];
  91         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
  92         if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
  93                 while (dp->flags & VRING_DESC_F_NEXT) {
  94                         desc_idx_last = dp->next;
  95                         dp = &vq->vq_ring.desc[dp->next];
  96                 }
  97         }
  98         dxp->ndescs = 0;
  99
 100         /*
 101          * We must append the existing free chain, if any, to the end of
 102          * newly freed chain. If the virtqueue was completely used, then
 103          * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
 104          */
 105         if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
 106                 vq->vq_desc_head_idx = desc_idx;
 107         } else {
 108                 dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
 109                 dp_tail->next = desc_idx;
 110         }
 111
 112         vq->vq_desc_tail_idx = desc_idx_last;
 113         dp->next = VQ_RING_DESC_CHAIN_END;
 114 }
 115
 116 static uint16_t
 117 virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
 118                            uint32_t *len, uint16_t num)
 119 {
 120         struct vring_used_elem *uep;
 121         struct rte_mbuf *cookie;
 122         uint16_t used_idx, desc_idx;
 123         uint16_t i;
 124
 125         /*  Caller does the check */
 126         for (i = 0; i < num ; i++) {
 127                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 128                 uep = &vq->vq_ring.used->ring[used_idx];
 129                 desc_idx = (uint16_t) uep->id;
 130                 len[i] = uep->len;
 131                 cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
 132
 133                 if (unlikely(cookie == NULL)) {
 134                         PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u",
 135                                 vq->vq_used_cons_idx);
 136                         break;
 137                 }
 138
 139                 rte_prefetch0(cookie);
 140                 rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
 141                 rx_pkts[i]  = cookie;
 142                 vq->vq_used_cons_idx++;
 143                 vq_ring_free_chain(vq, desc_idx);
 144                 vq->vq_descx[desc_idx].cookie = NULL;
 145         }
 146
 147         return i;
 148 }
 149
 150 #ifndef DEFAULT_TX_FREE_THRESH
 151 #define DEFAULT_TX_FREE_THRESH 32
 152 #endif
 153
 154 /* Cleanup from completed transmits. */
 155 static void
 156 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
 157 {
 158         uint16_t i, used_idx, desc_idx;
 159         for (i = 0; i < num; i++) {
 160                 struct vring_used_elem *uep;
 161                 struct vq_desc_extra *dxp;
 162
 163                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 164                 uep = &vq->vq_ring.used->ring[used_idx];
 165
 166                 desc_idx = (uint16_t) uep->id;
 167                 dxp = &vq->vq_descx[desc_idx];
 168                 vq->vq_used_cons_idx++;
 169                 vq_ring_free_chain(vq, desc_idx);
 170
 171                 if (dxp->cookie != NULL) {
 172                         rte_pktmbuf_free(dxp->cookie);
 173                         dxp->cookie = NULL;
 174                 }
 175         }
 176 }
 177
 178
 179 static inline int
 180 virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
 181 {
 182         struct vq_desc_extra *dxp;
 183         struct virtio_hw *hw = vq->hw;
 184         struct vring_desc *start_dp;
 185         uint16_t needed = 1;
 186         uint16_t head_idx, idx;
 187
 188         if (unlikely(vq->vq_free_cnt == 0))
 189                 return -ENOSPC;
 190         if (unlikely(vq->vq_free_cnt < needed))
 191                 return -EMSGSIZE;
 192
 193         head_idx = vq->vq_desc_head_idx;
 194         if (unlikely(head_idx >= vq->vq_nentries))
 195                 return -EFAULT;
 196
 197         idx = head_idx;
 198         dxp = &vq->vq_descx[idx];
 199         dxp->cookie = (void *)cookie;
 200         dxp->ndescs = needed;
 201
 202         start_dp = vq->vq_ring.desc;
 203         start_dp[idx].addr =
 204                 VIRTIO_MBUF_ADDR(cookie, vq) +
 205                 RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
 206         start_dp[idx].len =
 207                 cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 208         start_dp[idx].flags =  VRING_DESC_F_WRITE;
 209         idx = start_dp[idx].next;
 210         vq->vq_desc_head_idx = idx;
 211         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 212                 vq->vq_desc_tail_idx = idx;
 213         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 214         vq_update_avail_ring(vq, head_idx);
 215
 216         return 0;
 217 }
 218
 219 /* When doing TSO, the IP length is not included in the pseudo header
 220  * checksum of the packet given to the PMD, but for virtio it is
 221  * expected.
 222  */
 223 static void
 224 virtio_tso_fix_cksum(struct rte_mbuf *m)
 225 {
 226         /* common case: header is not fragmented */
 227         if (likely(rte_pktmbuf_data_len(m) >= m->l2_len + m->l3_len +
 228                         m->l4_len)) {
 229                 struct ipv4_hdr *iph;
 230                 struct ipv6_hdr *ip6h;
 231                 struct tcp_hdr *th;
 232                 uint16_t prev_cksum, new_cksum, ip_len, ip_paylen;
 233                 uint32_t tmp;
 234
 235                 iph = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *, m->l2_len);
 236                 th = RTE_PTR_ADD(iph, m->l3_len);
 237                 if ((iph->version_ihl >> 4) == 4) {
 238                         iph->hdr_checksum = 0;
 239                         iph->hdr_checksum = rte_ipv4_cksum(iph);
 240                         ip_len = iph->total_length;
 241                         ip_paylen = rte_cpu_to_be_16(rte_be_to_cpu_16(ip_len) -
 242                                 m->l3_len);
 243                 } else {
 244                         ip6h = (struct ipv6_hdr *)iph;
 245                         ip_paylen = ip6h->payload_len;
 246                 }
 247
 248                 /* calculate the new phdr checksum not including ip_paylen */
 249                 prev_cksum = th->cksum;
 250                 tmp = prev_cksum;
 251                 tmp += ip_paylen;
 252                 tmp = (tmp & 0xffff) + (tmp >> 16);
 253                 new_cksum = tmp;
 254
 255                 /* replace it in the packet */
 256                 th->cksum = new_cksum;
 257         }
 258 }
 259
 260 static inline int
 261 tx_offload_enabled(struct virtio_hw *hw)
 262 {
 263         return vtpci_with_feature(hw, VIRTIO_NET_F_CSUM) ||
 264                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO4) ||
 265                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO6);
 266 }
 267
 268 /* avoid write operation when necessary, to lessen cache issues */
 269 #define ASSIGN_UNLESS_EQUAL(var, val) do {      \
 270         if ((var) != (val))                     \
 271                 (var) = (val);                  \
 272 } while (0)
 273
 274 static inline void
 275 virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
 276                        uint16_t needed, int use_indirect, int can_push)
 277 {
 278         struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
 279         struct vq_desc_extra *dxp;
 280         struct virtqueue *vq = txvq->vq;
 281         struct vring_desc *start_dp;
 282         uint16_t seg_num = cookie->nb_segs;
 283         uint16_t head_idx, idx;
 284         uint16_t head_size = vq->hw->vtnet_hdr_size;
 285         struct virtio_net_hdr *hdr;
 286         int offload;
 287
 288         offload = tx_offload_enabled(vq->hw);
 289         head_idx = vq->vq_desc_head_idx;
 290         idx = head_idx;
 291         dxp = &vq->vq_descx[idx];
 292         dxp->cookie = (void *)cookie;
 293         dxp->ndescs = needed;
 294
 295         start_dp = vq->vq_ring.desc;
 296
 297         if (can_push) {
 298                 /* prepend cannot fail, checked by caller */
 299                 hdr = (struct virtio_net_hdr *)
 300                         rte_pktmbuf_prepend(cookie, head_size);
 301                 /* rte_pktmbuf_prepend() counts the hdr size to the pkt length,
 302                  * which is wrong. Below subtract restores correct pkt size.
 303                  */
 304                 cookie->pkt_len -= head_size;
 305                 /* if offload disabled, it is not zeroed below, do it now */
 306                 if (offload == 0) {
 307                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 308                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 309                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 310                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 311                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 312                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 313                 }
 314         } else if (use_indirect) {
 315                 /* setup tx ring slot to point to indirect
 316                  * descriptor list stored in reserved region.
 317                  *
 318                  * the first slot in indirect ring is already preset
 319                  * to point to the header in reserved region
 320                  */
 321                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 322                         RTE_PTR_DIFF(&txr[idx].tx_indir, txr);
 323                 start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
 324                 start_dp[idx].flags = VRING_DESC_F_INDIRECT;
 325                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 326
 327                 /* loop below will fill in rest of the indirect elements */
 328                 start_dp = txr[idx].tx_indir;
 329                 idx = 1;
 330         } else {
 331                 /* setup first tx ring slot to point to header
 332                  * stored in reserved region.
 333                  */
 334                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 335                         RTE_PTR_DIFF(&txr[idx].tx_hdr, txr);
 336                 start_dp[idx].len   = vq->hw->vtnet_hdr_size;
 337                 start_dp[idx].flags = VRING_DESC_F_NEXT;
 338                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 339
 340                 idx = start_dp[idx].next;
 341         }
 342
 343         /* Checksum Offload / TSO */
 344         if (offload) {
 345                 if (cookie->ol_flags & PKT_TX_TCP_SEG)
 346                         cookie->ol_flags |= PKT_TX_TCP_CKSUM;
 347
 348                 switch (cookie->ol_flags & PKT_TX_L4_MASK) {
 349                 case PKT_TX_UDP_CKSUM:
 350                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 351                         hdr->csum_offset = offsetof(struct udp_hdr,
 352                                 dgram_cksum);
 353                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 354                         break;
 355
 356                 case PKT_TX_TCP_CKSUM:
 357                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 358                         hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
 359                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 360                         break;
 361
 362                 default:
 363                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 364                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 365                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 366                         break;
 367                 }
 368
 369                 /* TCP Segmentation Offload */
 370                 if (cookie->ol_flags & PKT_TX_TCP_SEG) {
 371                         virtio_tso_fix_cksum(cookie);
 372                         hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
 373                                 VIRTIO_NET_HDR_GSO_TCPV6 :
 374                                 VIRTIO_NET_HDR_GSO_TCPV4;
 375                         hdr->gso_size = cookie->tso_segsz;
 376                         hdr->hdr_len =
 377                                 cookie->l2_len +
 378                                 cookie->l3_len +
 379                                 cookie->l4_len;
 380                 } else {
 381                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 382                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 383                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 384                 }
 385         }
 386
 387         do {
 388                 start_dp[idx].addr  = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
 389                 start_dp[idx].len   = cookie->data_len;
 390                 start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
 391                 idx = start_dp[idx].next;
 392         } while ((cookie = cookie->next) != NULL);
 393
 394         if (use_indirect)
 395                 idx = vq->vq_ring.desc[head_idx].next;
 396
 397         vq->vq_desc_head_idx = idx;
 398         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 399                 vq->vq_desc_tail_idx = idx;
 400         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 401         vq_update_avail_ring(vq, head_idx);
 402 }
 403
 404 void
 405 virtio_dev_cq_start(struct rte_eth_dev *dev)
 406 {
 407         struct virtio_hw *hw = dev->data->dev_private;
 408
 409         if (hw->cvq && hw->cvq->vq) {
 410                 VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq->vq);
 411         }
 412 }
 413
 414 int
 415 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 416                         uint16_t queue_idx,
 417                         uint16_t nb_desc,
 418                         unsigned int socket_id __rte_unused,
 419                         __rte_unused const struct rte_eth_rxconf *rx_conf,
 420                         struct rte_mempool *mp)
 421 {
 422         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 423         struct virtio_hw *hw = dev->data->dev_private;
 424         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 425         struct virtnet_rx *rxvq;
 426
 427         PMD_INIT_FUNC_TRACE();
 428
 429         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 430                 nb_desc = vq->vq_nentries;
 431         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 432
 433         rxvq = &vq->rxq;
 434         rxvq->queue_id = queue_idx;
 435         rxvq->mpool = mp;
 436         if (rxvq->mpool == NULL) {
 437                 rte_exit(EXIT_FAILURE,
 438                         "Cannot allocate mbufs for rx virtqueue");
 439         }
 440         dev->data->rx_queues[queue_idx] = rxvq;
 441
 442         return 0;
 443 }
 444
 445 int
 446 virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev, uint16_t queue_idx)
 447 {
 448         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 449         struct virtio_hw *hw = dev->data->dev_private;
 450         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 451         struct virtnet_rx *rxvq = &vq->rxq;
 452         struct rte_mbuf *m;
 453         uint16_t desc_idx;
 454         int error, nbufs;
 455
 456         PMD_INIT_FUNC_TRACE();
 457
 458         /* Allocate blank mbufs for the each rx descriptor */
 459         nbufs = 0;
 460
 461         if (hw->use_simple_rx) {
 462                 for (desc_idx = 0; desc_idx < vq->vq_nentries;
 463                      desc_idx++) {
 464                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 465                         vq->vq_ring.desc[desc_idx].flags =
 466                                 VRING_DESC_F_WRITE;
 467                 }
 468         }
 469
 470         memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
 471         for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST;
 472              desc_idx++) {
 473                 vq->sw_ring[vq->vq_nentries + desc_idx] =
 474                         &rxvq->fake_mbuf;
 475         }
 476
 477         while (!virtqueue_full(vq)) {
 478                 m = rte_mbuf_raw_alloc(rxvq->mpool);
 479                 if (m == NULL)
 480                         break;
 481
 482                 /* Enqueue allocated buffers */
 483                 if (hw->use_simple_rx)
 484                         error = virtqueue_enqueue_recv_refill_simple(vq, m);
 485                 else
 486                         error = virtqueue_enqueue_recv_refill(vq, m);
 487
 488                 if (error) {
 489                         rte_pktmbuf_free(m);
 490                         break;
 491                 }
 492                 nbufs++;
 493         }
 494
 495         vq_update_avail_idx(vq);
 496
 497         PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
 498
 499         virtio_rxq_vec_setup(rxvq);
 500
 501         VIRTQUEUE_DUMP(vq);
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * struct rte_eth_dev *dev: Used to update dev
 508  * uint16_t nb_desc: Defaults to values read from config space
 509  * unsigned int socket_id: Used to allocate memzone
 510  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
 511  * uint16_t queue_idx: Just used as an index in dev txq list
 512  */
 513 int
 514 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 515                         uint16_t queue_idx,
 516                         uint16_t nb_desc,
 517                         unsigned int socket_id __rte_unused,
 518                         const struct rte_eth_txconf *tx_conf)
 519 {
 520         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 521         struct virtio_hw *hw = dev->data->dev_private;
 522         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 523         struct virtnet_tx *txvq;
 524         uint16_t tx_free_thresh;
 525
 526         PMD_INIT_FUNC_TRACE();
 527
 528         /* cannot use simple rxtx funcs with multisegs or offloads */
 529         if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) != VIRTIO_SIMPLE_FLAGS)
 530                 hw->use_simple_tx = 0;
 531
 532         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 533                 nb_desc = vq->vq_nentries;
 534         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 535
 536         txvq = &vq->txq;
 537         txvq->queue_id = queue_idx;
 538
 539         tx_free_thresh = tx_conf->tx_free_thresh;
 540         if (tx_free_thresh == 0)
 541                 tx_free_thresh =
 542                         RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
 543
 544         if (tx_free_thresh >= (vq->vq_nentries - 3)) {
 545                 RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
 546                         "number of TX entries minus 3 (%u)."
 547                         " (tx_free_thresh=%u port=%u queue=%u)\n",
 548                         vq->vq_nentries - 3,
 549                         tx_free_thresh, dev->data->port_id, queue_idx);
 550                 return -EINVAL;
 551         }
 552
 553         vq->vq_free_thresh = tx_free_thresh;
 554
 555         dev->data->tx_queues[queue_idx] = txvq;
 556         return 0;
 557 }
 558
 559 int
 560 virtio_dev_tx_queue_setup_finish(struct rte_eth_dev *dev,
 561                                 uint16_t queue_idx)
 562 {
 563         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 564         struct virtio_hw *hw = dev->data->dev_private;
 565         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 566         uint16_t mid_idx = vq->vq_nentries >> 1;
 567         struct virtnet_tx *txvq = &vq->txq;
 568         uint16_t desc_idx;
 569
 570         PMD_INIT_FUNC_TRACE();
 571
 572         if (hw->use_simple_tx) {
 573                 for (desc_idx = 0; desc_idx < mid_idx; desc_idx++) {
 574                         vq->vq_ring.avail->ring[desc_idx] =
 575                                 desc_idx + mid_idx;
 576                         vq->vq_ring.desc[desc_idx + mid_idx].next =
 577                                 desc_idx;
 578                         vq->vq_ring.desc[desc_idx + mid_idx].addr =
 579                                 txvq->virtio_net_hdr_mem +
 580                                 offsetof(struct virtio_tx_region, tx_hdr);
 581                         vq->vq_ring.desc[desc_idx + mid_idx].len =
 582                                 vq->hw->vtnet_hdr_size;
 583                         vq->vq_ring.desc[desc_idx + mid_idx].flags =
 584                                 VRING_DESC_F_NEXT;
 585                         vq->vq_ring.desc[desc_idx].flags = 0;
 586                 }
 587                 for (desc_idx = mid_idx; desc_idx < vq->vq_nentries;
 588                      desc_idx++)
 589                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 590         }
 591
 592         VIRTQUEUE_DUMP(vq);
 593
 594         return 0;
 595 }
 596
 597 static void
 598 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
 599 {
 600         int error;
 601         /*
 602          * Requeue the discarded mbuf. This should always be
 603          * successful since it was just dequeued.
 604          */
 605         error = virtqueue_enqueue_recv_refill(vq, m);
 606         if (unlikely(error)) {
 607                 RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
 608                 rte_pktmbuf_free(m);
 609         }
 610 }
 611
 612 static void
 613 virtio_update_packet_stats(struct virtnet_stats *stats, struct rte_mbuf *mbuf)
 614 {
 615         uint32_t s = mbuf->pkt_len;
 616         struct ether_addr *ea;
 617
 618         if (s == 64) {
 619                 stats->size_bins[1]++;
 620         } else if (s > 64 && s < 1024) {
 621                 uint32_t bin;
 622
 623                 /* count zeros, and offset into correct bin */
 624                 bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
 625                 stats->size_bins[bin]++;
 626         } else {
 627                 if (s < 64)
 628                         stats->size_bins[0]++;
 629                 else if (s < 1519)
 630                         stats->size_bins[6]++;
 631                 else if (s >= 1519)
 632                         stats->size_bins[7]++;
 633         }
 634
 635         ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
 636         if (is_multicast_ether_addr(ea)) {
 637                 if (is_broadcast_ether_addr(ea))
 638                         stats->broadcast++;
 639                 else
 640                         stats->multicast++;
 641         }
 642 }
 643
 644 /* Optionally fill offload information in structure */
 645 static int
 646 virtio_rx_offload(struct rte_mbuf *m, struct virtio_net_hdr *hdr)
 647 {
 648         struct rte_net_hdr_lens hdr_lens;
 649         uint32_t hdrlen, ptype;
 650         int l4_supported = 0;
 651
 652         /* nothing to do */
 653         if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE)
 654                 return 0;
 655
 656         m->ol_flags |= PKT_RX_IP_CKSUM_UNKNOWN;
 657
 658         ptype = rte_net_get_ptype(m, &hdr_lens, RTE_PTYPE_ALL_MASK);
 659         m->packet_type = ptype;
 660         if ((ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_TCP ||
 661             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_UDP ||
 662             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_SCTP)
 663                 l4_supported = 1;
 664
 665         if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 666                 hdrlen = hdr_lens.l2_len + hdr_lens.l3_len + hdr_lens.l4_len;
 667                 if (hdr->csum_start <= hdrlen && l4_supported) {
 668                         m->ol_flags |= PKT_RX_L4_CKSUM_NONE;
 669                 } else {
 670                         /* Unknown proto or tunnel, do sw cksum. We can assume
 671                          * the cksum field is in the first segment since the
 672                          * buffers we provided to the host are large enough.
 673                          * In case of SCTP, this will be wrong since it's a CRC
 674                          * but there's nothing we can do.
 675                          */
 676                         uint16_t csum = 0, off;
 677
 678                         rte_raw_cksum_mbuf(m, hdr->csum_start,
 679                                 rte_pktmbuf_pkt_len(m) - hdr->csum_start,
 680                                 &csum);
 681                         if (likely(csum != 0xffff))
 682                                 csum = ~csum;
 683                         off = hdr->csum_offset + hdr->csum_start;
 684                         if (rte_pktmbuf_data_len(m) >= off + 1)
 685                                 *rte_pktmbuf_mtod_offset(m, uint16_t *,
 686                                         off) = csum;
 687                 }
 688         } else if (hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID && l4_supported) {
 689                 m->ol_flags |= PKT_RX_L4_CKSUM_GOOD;
 690         }
 691
 692         /* GSO request, save required information in mbuf */
 693         if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 694                 /* Check unsupported modes */
 695                 if ((hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) ||
 696                     (hdr->gso_size == 0)) {
 697                         return -EINVAL;
 698                 }
 699
 700                 /* Update mss lengthes in mbuf */
 701                 m->tso_segsz = hdr->gso_size;
 702                 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 703                         case VIRTIO_NET_HDR_GSO_TCPV4:
 704                         case VIRTIO_NET_HDR_GSO_TCPV6:
 705                                 m->ol_flags |= PKT_RX_LRO | \
 706                                         PKT_RX_L4_CKSUM_NONE;
 707                                 break;
 708                         default:
 709                                 return -EINVAL;
 710                 }
 711         }
 712
 713         return 0;
 714 }
 715
 716 static inline int
 717 rx_offload_enabled(struct virtio_hw *hw)
 718 {
 719         return vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_CSUM) ||
 720                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4) ||
 721                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO6);
 722 }
 723
 724 #define VIRTIO_MBUF_BURST_SZ 64
 725 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
 726 uint16_t
 727 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 728 {
 729         struct virtnet_rx *rxvq = rx_queue;
 730         struct virtqueue *vq = rxvq->vq;
 731         struct virtio_hw *hw = vq->hw;
 732         struct rte_mbuf *rxm, *new_mbuf;
 733         uint16_t nb_used, num, nb_rx;
 734         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 735         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 736         int error;
 737         uint32_t i, nb_enqueued;
 738         uint32_t hdr_size;
 739         int offload;
 740         struct virtio_net_hdr *hdr;
 741
 742         nb_rx = 0;
 743         if (unlikely(hw->started == 0))
 744                 return nb_rx;
 745
 746         nb_used = VIRTQUEUE_NUSED(vq);
 747
 748         virtio_rmb();
 749
 750         num = likely(nb_used <= nb_pkts) ? nb_used : nb_pkts;
 751         if (unlikely(num > VIRTIO_MBUF_BURST_SZ))
 752                 num = VIRTIO_MBUF_BURST_SZ;
 753         if (likely(num > DESC_PER_CACHELINE))
 754                 num = num - ((vq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
 755
 756         num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, num);
 757         PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
 758
 759         nb_enqueued = 0;
 760         hdr_size = hw->vtnet_hdr_size;
 761         offload = rx_offload_enabled(hw);
 762
 763         for (i = 0; i < num ; i++) {
 764                 rxm = rcv_pkts[i];
 765
 766                 PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
 767
 768                 if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
 769                         PMD_RX_LOG(ERR, "Packet drop");
 770                         nb_enqueued++;
 771                         virtio_discard_rxbuf(vq, rxm);
 772                         rxvq->stats.errors++;
 773                         continue;
 774                 }
 775
 776                 rxm->port = rxvq->port_id;
 777                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 778                 rxm->ol_flags = 0;
 779                 rxm->vlan_tci = 0;
 780
 781                 rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
 782                 rxm->data_len = (uint16_t)(len[i] - hdr_size);
 783
 784                 hdr = (struct virtio_net_hdr *)((char *)rxm->buf_addr +
 785                         RTE_PKTMBUF_HEADROOM - hdr_size);
 786
 787                 if (hw->vlan_strip)
 788                         rte_vlan_strip(rxm);
 789
 790                 if (offload && virtio_rx_offload(rxm, hdr) < 0) {
 791                         virtio_discard_rxbuf(vq, rxm);
 792                         rxvq->stats.errors++;
 793                         continue;
 794                 }
 795
 796                 VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
 797
 798                 rx_pkts[nb_rx++] = rxm;
 799
 800                 rxvq->stats.bytes += rxm->pkt_len;
 801                 virtio_update_packet_stats(&rxvq->stats, rxm);
 802         }
 803
 804         rxvq->stats.packets += nb_rx;
 805
 806         /* Allocate new mbuf for the used descriptor */
 807         error = ENOSPC;
 808         while (likely(!virtqueue_full(vq))) {
 809                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 810                 if (unlikely(new_mbuf == NULL)) {
 811                         struct rte_eth_dev *dev
 812                                 = &rte_eth_devices[rxvq->port_id];
 813                         dev->data->rx_mbuf_alloc_failed++;
 814                         break;
 815                 }
 816                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 817                 if (unlikely(error)) {
 818                         rte_pktmbuf_free(new_mbuf);
 819                         break;
 820                 }
 821                 nb_enqueued++;
 822         }
 823
 824         if (likely(nb_enqueued)) {
 825                 vq_update_avail_idx(vq);
 826
 827                 if (unlikely(virtqueue_kick_prepare(vq))) {
 828                         virtqueue_notify(vq);
 829                         PMD_RX_LOG(DEBUG, "Notified");
 830                 }
 831         }
 832
 833         return nb_rx;
 834 }
 835
 836 uint16_t
 837 virtio_recv_mergeable_pkts(void *rx_queue,
 838                         struct rte_mbuf **rx_pkts,
 839                         uint16_t nb_pkts)
 840 {
 841         struct virtnet_rx *rxvq = rx_queue;
 842         struct virtqueue *vq = rxvq->vq;
 843         struct virtio_hw *hw = vq->hw;
 844         struct rte_mbuf *rxm, *new_mbuf;
 845         uint16_t nb_used, num, nb_rx;
 846         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 847         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 848         struct rte_mbuf *prev;
 849         int error;
 850         uint32_t i, nb_enqueued;
 851         uint32_t seg_num;
 852         uint16_t extra_idx;
 853         uint32_t seg_res;
 854         uint32_t hdr_size;
 855         int offload;
 856
 857         nb_rx = 0;
 858         if (unlikely(hw->started == 0))
 859                 return nb_rx;
 860
 861         nb_used = VIRTQUEUE_NUSED(vq);
 862
 863         virtio_rmb();
 864
 865         PMD_RX_LOG(DEBUG, "used:%d", nb_used);
 866
 867         i = 0;
 868         nb_enqueued = 0;
 869         seg_num = 0;
 870         extra_idx = 0;
 871         seg_res = 0;
 872         hdr_size = hw->vtnet_hdr_size;
 873         offload = rx_offload_enabled(hw);
 874
 875         while (i < nb_used) {
 876                 struct virtio_net_hdr_mrg_rxbuf *header;
 877
 878                 if (nb_rx == nb_pkts)
 879                         break;
 880
 881                 num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, 1);
 882                 if (num != 1)
 883                         continue;
 884
 885                 i++;
 886
 887                 PMD_RX_LOG(DEBUG, "dequeue:%d", num);
 888                 PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
 889
 890                 rxm = rcv_pkts[0];
 891
 892                 if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
 893                         PMD_RX_LOG(ERR, "Packet drop");
 894                         nb_enqueued++;
 895                         virtio_discard_rxbuf(vq, rxm);
 896                         rxvq->stats.errors++;
 897                         continue;
 898                 }
 899
 900                 header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
 901                         RTE_PKTMBUF_HEADROOM - hdr_size);
 902                 seg_num = header->num_buffers;
 903
 904                 if (seg_num == 0)
 905                         seg_num = 1;
 906
 907                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 908                 rxm->nb_segs = seg_num;
 909                 rxm->ol_flags = 0;
 910                 rxm->vlan_tci = 0;
 911                 rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
 912                 rxm->data_len = (uint16_t)(len[0] - hdr_size);
 913
 914                 rxm->port = rxvq->port_id;
 915                 rx_pkts[nb_rx] = rxm;
 916                 prev = rxm;
 917
 918                 if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
 919                         virtio_discard_rxbuf(vq, rxm);
 920                         rxvq->stats.errors++;
 921                         continue;
 922                 }
 923
 924                 seg_res = seg_num - 1;
 925
 926                 while (seg_res != 0) {
 927                         /*
 928                          * Get extra segments for current uncompleted packet.
 929                          */
 930                         uint16_t  rcv_cnt =
 931                                 RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
 932                         if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
 933                                 uint32_t rx_num =
 934                                         virtqueue_dequeue_burst_rx(vq,
 935                                         rcv_pkts, len, rcv_cnt);
 936                                 i += rx_num;
 937                                 rcv_cnt = rx_num;
 938                         } else {
 939                                 PMD_RX_LOG(ERR,
 940                                            "No enough segments for packet.");
 941                                 nb_enqueued++;
 942                                 virtio_discard_rxbuf(vq, rxm);
 943                                 rxvq->stats.errors++;
 944                                 break;
 945                         }
 946
 947                         extra_idx = 0;
 948
 949                         while (extra_idx < rcv_cnt) {
 950                                 rxm = rcv_pkts[extra_idx];
 951
 952                                 rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
 953                                 rxm->pkt_len = (uint32_t)(len[extra_idx]);
 954                                 rxm->data_len = (uint16_t)(len[extra_idx]);
 955
 956                                 if (prev)
 957                                         prev->next = rxm;
 958
 959                                 prev = rxm;
 960                                 rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
 961                                 extra_idx++;
 962                         };
 963                         seg_res -= rcv_cnt;
 964                 }
 965
 966                 if (hw->vlan_strip)
 967                         rte_vlan_strip(rx_pkts[nb_rx]);
 968
 969                 VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
 970                         rx_pkts[nb_rx]->data_len);
 971
 972                 rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
 973                 virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
 974                 nb_rx++;
 975         }
 976
 977         rxvq->stats.packets += nb_rx;
 978
 979         /* Allocate new mbuf for the used descriptor */
 980         error = ENOSPC;
 981         while (likely(!virtqueue_full(vq))) {
 982                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 983                 if (unlikely(new_mbuf == NULL)) {
 984                         struct rte_eth_dev *dev
 985                                 = &rte_eth_devices[rxvq->port_id];
 986                         dev->data->rx_mbuf_alloc_failed++;
 987                         break;
 988                 }
 989                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 990                 if (unlikely(error)) {
 991                         rte_pktmbuf_free(new_mbuf);
 992                         break;
 993                 }
 994                 nb_enqueued++;
 995         }
 996
 997         if (likely(nb_enqueued)) {
 998                 vq_update_avail_idx(vq);
 999
1000                 if (unlikely(virtqueue_kick_prepare(vq))) {
1001                         virtqueue_notify(vq);
1002                         PMD_RX_LOG(DEBUG, "Notified");
1003                 }
1004         }
1005
1006         return nb_rx;
1007 }
1008
1009 uint16_t
1010 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
1011 {
1012         struct virtnet_tx *txvq = tx_queue;
1013         struct virtqueue *vq = txvq->vq;
1014         struct virtio_hw *hw = vq->hw;
1015         uint16_t hdr_size = hw->vtnet_hdr_size;
1016         uint16_t nb_used, nb_tx = 0;
1017         int error;
1018
1019         if (unlikely(hw->started == 0))
1020                 return nb_tx;
1021
1022         if (unlikely(nb_pkts < 1))
1023                 return nb_pkts;
1024
1025         PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
1026         nb_used = VIRTQUEUE_NUSED(vq);
1027
1028         virtio_rmb();
1029         if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
1030                 virtio_xmit_cleanup(vq, nb_used);
1031
1032         for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
1033                 struct rte_mbuf *txm = tx_pkts[nb_tx];
1034                 int can_push = 0, use_indirect = 0, slots, need;
1035
1036                 /* Do VLAN tag insertion */
1037                 if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
1038                         error = rte_vlan_insert(&txm);
1039                         if (unlikely(error)) {
1040                                 rte_pktmbuf_free(txm);
1041                                 continue;
1042                         }
1043                 }
1044
1045                 /* optimize ring usage */
1046                 if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
1047                       vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
1048                     rte_mbuf_refcnt_read(txm) == 1 &&
1049                     RTE_MBUF_DIRECT(txm) &&
1050                     txm->nb_segs == 1 &&
1051                     rte_pktmbuf_headroom(txm) >= hdr_size &&
1052                     rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
1053                                    __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
1054                         can_push = 1;
1055                 else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
1056                          txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
1057                         use_indirect = 1;
1058
1059                 /* How many main ring entries are needed to this Tx?
1060                  * any_layout => number of segments
1061                  * indirect   => 1
1062                  * default    => number of segments + 1
1063                  */
1064                 slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
1065                 need = slots - vq->vq_free_cnt;
1066
1067                 /* Positive value indicates it need free vring descriptors */
1068                 if (unlikely(need > 0)) {
1069                         nb_used = VIRTQUEUE_NUSED(vq);
1070                         virtio_rmb();
1071                         need = RTE_MIN(need, (int)nb_used);
1072
1073                         virtio_xmit_cleanup(vq, need);
1074                         need = slots - vq->vq_free_cnt;
1075                         if (unlikely(need > 0)) {
1076                                 PMD_TX_LOG(ERR,
1077                                            "No free tx descriptors to transmit");
1078                                 break;
1079                         }
1080                 }
1081
1082                 /* Enqueue Packet buffers */
1083                 virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
1084
1085                 txvq->stats.bytes += txm->pkt_len;
1086                 virtio_update_packet_stats(&txvq->stats, txm);
1087         }
1088
1089         txvq->stats.packets += nb_tx;
1090
1091         if (likely(nb_tx)) {
1092                 vq_update_avail_idx(vq);
1093
1094                 if (unlikely(virtqueue_kick_prepare(vq))) {
1095                         virtqueue_notify(vq);
1096                         PMD_TX_LOG(DEBUG, "Notified backend after xmit");
1097                 }
1098         }
1099
1100         return nb_tx;
1101 }