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_memzone.h>
  43 #include <rte_branch_prediction.h>
  44 #include <rte_mempool.h>
  45 #include <rte_malloc.h>
  46 #include <rte_mbuf.h>
  47 #include <rte_ether.h>
  48 #include <rte_ethdev.h>
  49 #include <rte_prefetch.h>
  50 #include <rte_string_fns.h>
  51 #include <rte_errno.h>
  52 #include <rte_byteorder.h>
  53 #include <rte_cpuflags.h>
  54 #include <rte_net.h>
  55 #include <rte_ip.h>
  56 #include <rte_udp.h>
  57 #include <rte_tcp.h>
  58
  59 #include "virtio_logs.h"
  60 #include "virtio_ethdev.h"
  61 #include "virtio_pci.h"
  62 #include "virtqueue.h"
  63 #include "virtio_rxtx.h"
  64
  65 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
  66 #define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
  67 #else
  68 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
  69 #endif
  70
  71
  72 #define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
  73         ETH_TXQ_FLAGS_NOOFFLOADS)
  74
  75 static void
  76 vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
  77 {
  78         struct vring_desc *dp, *dp_tail;
  79         struct vq_desc_extra *dxp;
  80         uint16_t desc_idx_last = desc_idx;
  81
  82         dp  = &vq->vq_ring.desc[desc_idx];
  83         dxp = &vq->vq_descx[desc_idx];
  84         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
  85         if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
  86                 while (dp->flags & VRING_DESC_F_NEXT) {
  87                         desc_idx_last = dp->next;
  88                         dp = &vq->vq_ring.desc[dp->next];
  89                 }
  90         }
  91         dxp->ndescs = 0;
  92
  93         /*
  94          * We must append the existing free chain, if any, to the end of
  95          * newly freed chain. If the virtqueue was completely used, then
  96          * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
  97          */
  98         if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
  99                 vq->vq_desc_head_idx = desc_idx;
 100         } else {
 101                 dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
 102                 dp_tail->next = desc_idx;
 103         }
 104
 105         vq->vq_desc_tail_idx = desc_idx_last;
 106         dp->next = VQ_RING_DESC_CHAIN_END;
 107 }
 108
 109 static uint16_t
 110 virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
 111                            uint32_t *len, uint16_t num)
 112 {
 113         struct vring_used_elem *uep;
 114         struct rte_mbuf *cookie;
 115         uint16_t used_idx, desc_idx;
 116         uint16_t i;
 117
 118         /*  Caller does the check */
 119         for (i = 0; i < num ; i++) {
 120                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 121                 uep = &vq->vq_ring.used->ring[used_idx];
 122                 desc_idx = (uint16_t) uep->id;
 123                 len[i] = uep->len;
 124                 cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
 125
 126                 if (unlikely(cookie == NULL)) {
 127                         PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
 128                                 vq->vq_used_cons_idx);
 129                         break;
 130                 }
 131
 132                 rte_prefetch0(cookie);
 133                 rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
 134                 rx_pkts[i]  = cookie;
 135                 vq->vq_used_cons_idx++;
 136                 vq_ring_free_chain(vq, desc_idx);
 137                 vq->vq_descx[desc_idx].cookie = NULL;
 138         }
 139
 140         return i;
 141 }
 142
 143 #ifndef DEFAULT_TX_FREE_THRESH
 144 #define DEFAULT_TX_FREE_THRESH 32
 145 #endif
 146
 147 /* Cleanup from completed transmits. */
 148 static void
 149 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
 150 {
 151         uint16_t i, used_idx, desc_idx;
 152         for (i = 0; i < num; i++) {
 153                 struct vring_used_elem *uep;
 154                 struct vq_desc_extra *dxp;
 155
 156                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 157                 uep = &vq->vq_ring.used->ring[used_idx];
 158
 159                 desc_idx = (uint16_t) uep->id;
 160                 dxp = &vq->vq_descx[desc_idx];
 161                 vq->vq_used_cons_idx++;
 162                 vq_ring_free_chain(vq, desc_idx);
 163
 164                 if (dxp->cookie != NULL) {
 165                         rte_pktmbuf_free(dxp->cookie);
 166                         dxp->cookie = NULL;
 167                 }
 168         }
 169 }
 170
 171
 172 static inline int
 173 virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
 174 {
 175         struct vq_desc_extra *dxp;
 176         struct virtio_hw *hw = vq->hw;
 177         struct vring_desc *start_dp;
 178         uint16_t needed = 1;
 179         uint16_t head_idx, idx;
 180
 181         if (unlikely(vq->vq_free_cnt == 0))
 182                 return -ENOSPC;
 183         if (unlikely(vq->vq_free_cnt < needed))
 184                 return -EMSGSIZE;
 185
 186         head_idx = vq->vq_desc_head_idx;
 187         if (unlikely(head_idx >= vq->vq_nentries))
 188                 return -EFAULT;
 189
 190         idx = head_idx;
 191         dxp = &vq->vq_descx[idx];
 192         dxp->cookie = (void *)cookie;
 193         dxp->ndescs = needed;
 194
 195         start_dp = vq->vq_ring.desc;
 196         start_dp[idx].addr =
 197                 VIRTIO_MBUF_ADDR(cookie, vq) +
 198                 RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
 199         start_dp[idx].len =
 200                 cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 201         start_dp[idx].flags =  VRING_DESC_F_WRITE;
 202         idx = start_dp[idx].next;
 203         vq->vq_desc_head_idx = idx;
 204         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 205                 vq->vq_desc_tail_idx = idx;
 206         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 207         vq_update_avail_ring(vq, head_idx);
 208
 209         return 0;
 210 }
 211
 212 /* When doing TSO, the IP length is not included in the pseudo header
 213  * checksum of the packet given to the PMD, but for virtio it is
 214  * expected.
 215  */
 216 static void
 217 virtio_tso_fix_cksum(struct rte_mbuf *m)
 218 {
 219         /* common case: header is not fragmented */
 220         if (likely(rte_pktmbuf_data_len(m) >= m->l2_len + m->l3_len +
 221                         m->l4_len)) {
 222                 struct ipv4_hdr *iph;
 223                 struct ipv6_hdr *ip6h;
 224                 struct tcp_hdr *th;
 225                 uint16_t prev_cksum, new_cksum, ip_len, ip_paylen;
 226                 uint32_t tmp;
 227
 228                 iph = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *, m->l2_len);
 229                 th = RTE_PTR_ADD(iph, m->l3_len);
 230                 if ((iph->version_ihl >> 4) == 4) {
 231                         iph->hdr_checksum = 0;
 232                         iph->hdr_checksum = rte_ipv4_cksum(iph);
 233                         ip_len = iph->total_length;
 234                         ip_paylen = rte_cpu_to_be_16(rte_be_to_cpu_16(ip_len) -
 235                                 m->l3_len);
 236                 } else {
 237                         ip6h = (struct ipv6_hdr *)iph;
 238                         ip_paylen = ip6h->payload_len;
 239                 }
 240
 241                 /* calculate the new phdr checksum not including ip_paylen */
 242                 prev_cksum = th->cksum;
 243                 tmp = prev_cksum;
 244                 tmp += ip_paylen;
 245                 tmp = (tmp & 0xffff) + (tmp >> 16);
 246                 new_cksum = tmp;
 247
 248                 /* replace it in the packet */
 249                 th->cksum = new_cksum;
 250         }
 251 }
 252
 253 static inline int
 254 tx_offload_enabled(struct virtio_hw *hw)
 255 {
 256         return vtpci_with_feature(hw, VIRTIO_NET_F_CSUM) ||
 257                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO4) ||
 258                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO6);
 259 }
 260
 261 static inline void
 262 virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
 263                        uint16_t needed, int use_indirect, int can_push)
 264 {
 265         struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
 266         struct vq_desc_extra *dxp;
 267         struct virtqueue *vq = txvq->vq;
 268         struct vring_desc *start_dp;
 269         uint16_t seg_num = cookie->nb_segs;
 270         uint16_t head_idx, idx;
 271         uint16_t head_size = vq->hw->vtnet_hdr_size;
 272         struct virtio_net_hdr *hdr;
 273         int offload;
 274
 275         offload = tx_offload_enabled(vq->hw);
 276         head_idx = vq->vq_desc_head_idx;
 277         idx = head_idx;
 278         dxp = &vq->vq_descx[idx];
 279         dxp->cookie = (void *)cookie;
 280         dxp->ndescs = needed;
 281
 282         start_dp = vq->vq_ring.desc;
 283
 284         if (can_push) {
 285                 /* prepend cannot fail, checked by caller */
 286                 hdr = (struct virtio_net_hdr *)
 287                         rte_pktmbuf_prepend(cookie, head_size);
 288                 /* if offload disabled, it is not zeroed below, do it now */
 289                 if (offload == 0)
 290                         memset(hdr, 0, head_size);
 291         } else if (use_indirect) {
 292                 /* setup tx ring slot to point to indirect
 293                  * descriptor list stored in reserved region.
 294                  *
 295                  * the first slot in indirect ring is already preset
 296                  * to point to the header in reserved region
 297                  */
 298                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 299                         RTE_PTR_DIFF(&txr[idx].tx_indir, txr);
 300                 start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
 301                 start_dp[idx].flags = VRING_DESC_F_INDIRECT;
 302                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 303
 304                 /* loop below will fill in rest of the indirect elements */
 305                 start_dp = txr[idx].tx_indir;
 306                 idx = 1;
 307         } else {
 308                 /* setup first tx ring slot to point to header
 309                  * stored in reserved region.
 310                  */
 311                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 312                         RTE_PTR_DIFF(&txr[idx].tx_hdr, txr);
 313                 start_dp[idx].len   = vq->hw->vtnet_hdr_size;
 314                 start_dp[idx].flags = VRING_DESC_F_NEXT;
 315                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 316
 317                 idx = start_dp[idx].next;
 318         }
 319
 320         /* Checksum Offload / TSO */
 321         if (offload) {
 322                 if (cookie->ol_flags & PKT_TX_TCP_SEG)
 323                         cookie->ol_flags |= PKT_TX_TCP_CKSUM;
 324
 325                 switch (cookie->ol_flags & PKT_TX_L4_MASK) {
 326                 case PKT_TX_UDP_CKSUM:
 327                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 328                         hdr->csum_offset = offsetof(struct udp_hdr,
 329                                 dgram_cksum);
 330                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 331                         break;
 332
 333                 case PKT_TX_TCP_CKSUM:
 334                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 335                         hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
 336                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 337                         break;
 338
 339                 default:
 340                         hdr->csum_start = 0;
 341                         hdr->csum_offset = 0;
 342                         hdr->flags = 0;
 343                         break;
 344                 }
 345
 346                 /* TCP Segmentation Offload */
 347                 if (cookie->ol_flags & PKT_TX_TCP_SEG) {
 348                         virtio_tso_fix_cksum(cookie);
 349                         hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
 350                                 VIRTIO_NET_HDR_GSO_TCPV6 :
 351                                 VIRTIO_NET_HDR_GSO_TCPV4;
 352                         hdr->gso_size = cookie->tso_segsz;
 353                         hdr->hdr_len =
 354                                 cookie->l2_len +
 355                                 cookie->l3_len +
 356                                 cookie->l4_len;
 357                 } else {
 358                         hdr->gso_type = 0;
 359                         hdr->gso_size = 0;
 360                         hdr->hdr_len = 0;
 361                 }
 362         }
 363
 364         do {
 365                 start_dp[idx].addr  = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
 366                 start_dp[idx].len   = cookie->data_len;
 367                 start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
 368                 idx = start_dp[idx].next;
 369         } while ((cookie = cookie->next) != NULL);
 370
 371         if (use_indirect)
 372                 idx = vq->vq_ring.desc[head_idx].next;
 373
 374         vq->vq_desc_head_idx = idx;
 375         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 376                 vq->vq_desc_tail_idx = idx;
 377         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 378         vq_update_avail_ring(vq, head_idx);
 379 }
 380
 381 void
 382 virtio_dev_cq_start(struct rte_eth_dev *dev)
 383 {
 384         struct virtio_hw *hw = dev->data->dev_private;
 385
 386         if (hw->cvq && hw->cvq->vq) {
 387                 VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq->vq);
 388         }
 389 }
 390
 391 int
 392 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 393                         uint16_t queue_idx,
 394                         uint16_t nb_desc,
 395                         unsigned int socket_id __rte_unused,
 396                         __rte_unused const struct rte_eth_rxconf *rx_conf,
 397                         struct rte_mempool *mp)
 398 {
 399         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 400         struct virtio_hw *hw = dev->data->dev_private;
 401         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 402         struct virtnet_rx *rxvq;
 403         int error, nbufs;
 404         struct rte_mbuf *m;
 405         uint16_t desc_idx;
 406
 407         PMD_INIT_FUNC_TRACE();
 408
 409         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 410                 nb_desc = vq->vq_nentries;
 411         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 412
 413         rxvq = &vq->rxq;
 414         rxvq->queue_id = queue_idx;
 415         rxvq->mpool = mp;
 416         if (rxvq->mpool == NULL) {
 417                 rte_exit(EXIT_FAILURE,
 418                         "Cannot allocate mbufs for rx virtqueue");
 419         }
 420         dev->data->rx_queues[queue_idx] = rxvq;
 421
 422
 423         /* Allocate blank mbufs for the each rx descriptor */
 424         nbufs = 0;
 425         error = ENOSPC;
 426
 427         if (hw->use_simple_rxtx) {
 428                 for (desc_idx = 0; desc_idx < vq->vq_nentries;
 429                      desc_idx++) {
 430                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 431                         vq->vq_ring.desc[desc_idx].flags =
 432                                 VRING_DESC_F_WRITE;
 433                 }
 434         }
 435
 436         memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
 437         for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST;
 438              desc_idx++) {
 439                 vq->sw_ring[vq->vq_nentries + desc_idx] =
 440                         &rxvq->fake_mbuf;
 441         }
 442
 443         while (!virtqueue_full(vq)) {
 444                 m = rte_mbuf_raw_alloc(rxvq->mpool);
 445                 if (m == NULL)
 446                         break;
 447
 448                 /* Enqueue allocated buffers */
 449                 if (hw->use_simple_rxtx)
 450                         error = virtqueue_enqueue_recv_refill_simple(vq, m);
 451                 else
 452                         error = virtqueue_enqueue_recv_refill(vq, m);
 453
 454                 if (error) {
 455                         rte_pktmbuf_free(m);
 456                         break;
 457                 }
 458                 nbufs++;
 459         }
 460
 461         vq_update_avail_idx(vq);
 462
 463         PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
 464
 465         virtio_rxq_vec_setup(rxvq);
 466
 467         VIRTQUEUE_DUMP(vq);
 468
 469         return 0;
 470 }
 471
 472 static void
 473 virtio_update_rxtx_handler(struct rte_eth_dev *dev,
 474                            const struct rte_eth_txconf *tx_conf)
 475 {
 476         uint8_t use_simple_rxtx = 0;
 477         struct virtio_hw *hw = dev->data->dev_private;
 478
 479 #if defined RTE_ARCH_X86
 480         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE3))
 481                 use_simple_rxtx = 1;
 482 #elif defined RTE_ARCH_ARM64 || defined CONFIG_RTE_ARCH_ARM
 483         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
 484                 use_simple_rxtx = 1;
 485 #endif
 486         /* Use simple rx/tx func if single segment and no offloads */
 487         if (use_simple_rxtx &&
 488             (tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
 489             !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
 490                 PMD_INIT_LOG(INFO, "Using simple rx/tx path");
 491                 dev->tx_pkt_burst = virtio_xmit_pkts_simple;
 492                 dev->rx_pkt_burst = virtio_recv_pkts_vec;
 493                 hw->use_simple_rxtx = use_simple_rxtx;
 494         }
 495 }
 496
 497 /*
 498  * struct rte_eth_dev *dev: Used to update dev
 499  * uint16_t nb_desc: Defaults to values read from config space
 500  * unsigned int socket_id: Used to allocate memzone
 501  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
 502  * uint16_t queue_idx: Just used as an index in dev txq list
 503  */
 504 int
 505 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 506                         uint16_t queue_idx,
 507                         uint16_t nb_desc,
 508                         unsigned int socket_id __rte_unused,
 509                         const struct rte_eth_txconf *tx_conf)
 510 {
 511         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 512         struct virtio_hw *hw = dev->data->dev_private;
 513         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 514         struct virtnet_tx *txvq;
 515         uint16_t tx_free_thresh;
 516         uint16_t desc_idx;
 517
 518         PMD_INIT_FUNC_TRACE();
 519
 520         virtio_update_rxtx_handler(dev, tx_conf);
 521
 522         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 523                 nb_desc = vq->vq_nentries;
 524         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 525
 526         txvq = &vq->txq;
 527         txvq->queue_id = queue_idx;
 528
 529         tx_free_thresh = tx_conf->tx_free_thresh;
 530         if (tx_free_thresh == 0)
 531                 tx_free_thresh =
 532                         RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
 533
 534         if (tx_free_thresh >= (vq->vq_nentries - 3)) {
 535                 RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
 536                         "number of TX entries minus 3 (%u)."
 537                         " (tx_free_thresh=%u port=%u queue=%u)\n",
 538                         vq->vq_nentries - 3,
 539                         tx_free_thresh, dev->data->port_id, queue_idx);
 540                 return -EINVAL;
 541         }
 542
 543         vq->vq_free_thresh = tx_free_thresh;
 544
 545         if (hw->use_simple_rxtx) {
 546                 uint16_t mid_idx  = vq->vq_nentries >> 1;
 547
 548                 for (desc_idx = 0; desc_idx < mid_idx; desc_idx++) {
 549                         vq->vq_ring.avail->ring[desc_idx] =
 550                                 desc_idx + mid_idx;
 551                         vq->vq_ring.desc[desc_idx + mid_idx].next =
 552                                 desc_idx;
 553                         vq->vq_ring.desc[desc_idx + mid_idx].addr =
 554                                 txvq->virtio_net_hdr_mem +
 555                                 offsetof(struct virtio_tx_region, tx_hdr);
 556                         vq->vq_ring.desc[desc_idx + mid_idx].len =
 557                                 vq->hw->vtnet_hdr_size;
 558                         vq->vq_ring.desc[desc_idx + mid_idx].flags =
 559                                 VRING_DESC_F_NEXT;
 560                         vq->vq_ring.desc[desc_idx].flags = 0;
 561                 }
 562                 for (desc_idx = mid_idx; desc_idx < vq->vq_nentries;
 563                      desc_idx++)
 564                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 565         }
 566
 567         VIRTQUEUE_DUMP(vq);
 568
 569         dev->data->tx_queues[queue_idx] = txvq;
 570         return 0;
 571 }
 572
 573 static void
 574 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
 575 {
 576         int error;
 577         /*
 578          * Requeue the discarded mbuf. This should always be
 579          * successful since it was just dequeued.
 580          */
 581         error = virtqueue_enqueue_recv_refill(vq, m);
 582         if (unlikely(error)) {
 583                 RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
 584                 rte_pktmbuf_free(m);
 585         }
 586 }
 587
 588 static void
 589 virtio_update_packet_stats(struct virtnet_stats *stats, struct rte_mbuf *mbuf)
 590 {
 591         uint32_t s = mbuf->pkt_len;
 592         struct ether_addr *ea;
 593
 594         if (s == 64) {
 595                 stats->size_bins[1]++;
 596         } else if (s > 64 && s < 1024) {
 597                 uint32_t bin;
 598
 599                 /* count zeros, and offset into correct bin */
 600                 bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
 601                 stats->size_bins[bin]++;
 602         } else {
 603                 if (s < 64)
 604                         stats->size_bins[0]++;
 605                 else if (s < 1519)
 606                         stats->size_bins[6]++;
 607                 else if (s >= 1519)
 608                         stats->size_bins[7]++;
 609         }
 610
 611         ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
 612         if (is_multicast_ether_addr(ea)) {
 613                 if (is_broadcast_ether_addr(ea))
 614                         stats->broadcast++;
 615                 else
 616                         stats->multicast++;
 617         }
 618 }
 619
 620 /* Optionally fill offload information in structure */
 621 static int
 622 virtio_rx_offload(struct rte_mbuf *m, struct virtio_net_hdr *hdr)
 623 {
 624         struct rte_net_hdr_lens hdr_lens;
 625         uint32_t hdrlen, ptype;
 626         int l4_supported = 0;
 627
 628         /* nothing to do */
 629         if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE)
 630                 return 0;
 631
 632         m->ol_flags |= PKT_RX_IP_CKSUM_UNKNOWN;
 633
 634         ptype = rte_net_get_ptype(m, &hdr_lens, RTE_PTYPE_ALL_MASK);
 635         m->packet_type = ptype;
 636         if ((ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_TCP ||
 637             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_UDP ||
 638             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_SCTP)
 639                 l4_supported = 1;
 640
 641         if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 642                 hdrlen = hdr_lens.l2_len + hdr_lens.l3_len + hdr_lens.l4_len;
 643                 if (hdr->csum_start <= hdrlen && l4_supported) {
 644                         m->ol_flags |= PKT_RX_L4_CKSUM_NONE;
 645                 } else {
 646                         /* Unknown proto or tunnel, do sw cksum. We can assume
 647                          * the cksum field is in the first segment since the
 648                          * buffers we provided to the host are large enough.
 649                          * In case of SCTP, this will be wrong since it's a CRC
 650                          * but there's nothing we can do.
 651                          */
 652                         uint16_t csum, off;
 653
 654                         rte_raw_cksum_mbuf(m, hdr->csum_start,
 655                                 rte_pktmbuf_pkt_len(m) - hdr->csum_start,
 656                                 &csum);
 657                         if (likely(csum != 0xffff))
 658                                 csum = ~csum;
 659                         off = hdr->csum_offset + hdr->csum_start;
 660                         if (rte_pktmbuf_data_len(m) >= off + 1)
 661                                 *rte_pktmbuf_mtod_offset(m, uint16_t *,
 662                                         off) = csum;
 663                 }
 664         } else if (hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID && l4_supported) {
 665                 m->ol_flags |= PKT_RX_L4_CKSUM_GOOD;
 666         }
 667
 668         /* GSO request, save required information in mbuf */
 669         if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 670                 /* Check unsupported modes */
 671                 if ((hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) ||
 672                     (hdr->gso_size == 0)) {
 673                         return -EINVAL;
 674                 }
 675
 676                 /* Update mss lengthes in mbuf */
 677                 m->tso_segsz = hdr->gso_size;
 678                 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 679                         case VIRTIO_NET_HDR_GSO_TCPV4:
 680                         case VIRTIO_NET_HDR_GSO_TCPV6:
 681                                 m->ol_flags |= PKT_RX_LRO | \
 682                                         PKT_RX_L4_CKSUM_NONE;
 683                                 break;
 684                         default:
 685                                 return -EINVAL;
 686                 }
 687         }
 688
 689         return 0;
 690 }
 691
 692 static inline int
 693 rx_offload_enabled(struct virtio_hw *hw)
 694 {
 695         return vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_CSUM) ||
 696                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4) ||
 697                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO6);
 698 }
 699
 700 #define VIRTIO_MBUF_BURST_SZ 64
 701 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
 702 uint16_t
 703 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 704 {
 705         struct virtnet_rx *rxvq = rx_queue;
 706         struct virtqueue *vq = rxvq->vq;
 707         struct virtio_hw *hw;
 708         struct rte_mbuf *rxm, *new_mbuf;
 709         uint16_t nb_used, num, nb_rx;
 710         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 711         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 712         int error;
 713         uint32_t i, nb_enqueued;
 714         uint32_t hdr_size;
 715         int offload;
 716         struct virtio_net_hdr *hdr;
 717
 718         nb_used = VIRTQUEUE_NUSED(vq);
 719
 720         virtio_rmb();
 721
 722         num = (uint16_t)(likely(nb_used <= nb_pkts) ? nb_used : nb_pkts);
 723         num = (uint16_t)(likely(num <= VIRTIO_MBUF_BURST_SZ) ? num : VIRTIO_MBUF_BURST_SZ);
 724         if (likely(num > DESC_PER_CACHELINE))
 725                 num = num - ((vq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
 726
 727         num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, num);
 728         PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
 729
 730         hw = vq->hw;
 731         nb_rx = 0;
 732         nb_enqueued = 0;
 733         hdr_size = hw->vtnet_hdr_size;
 734         offload = rx_offload_enabled(hw);
 735
 736         for (i = 0; i < num ; i++) {
 737                 rxm = rcv_pkts[i];
 738
 739                 PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
 740
 741                 if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
 742                         PMD_RX_LOG(ERR, "Packet drop");
 743                         nb_enqueued++;
 744                         virtio_discard_rxbuf(vq, rxm);
 745                         rxvq->stats.errors++;
 746                         continue;
 747                 }
 748
 749                 rxm->port = rxvq->port_id;
 750                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 751                 rxm->ol_flags = 0;
 752                 rxm->vlan_tci = 0;
 753
 754                 rxm->nb_segs = 1;
 755                 rxm->next = NULL;
 756                 rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
 757                 rxm->data_len = (uint16_t)(len[i] - hdr_size);
 758
 759                 hdr = (struct virtio_net_hdr *)((char *)rxm->buf_addr +
 760                         RTE_PKTMBUF_HEADROOM - hdr_size);
 761
 762                 if (hw->vlan_strip)
 763                         rte_vlan_strip(rxm);
 764
 765                 if (offload && virtio_rx_offload(rxm, hdr) < 0) {
 766                         virtio_discard_rxbuf(vq, rxm);
 767                         rxvq->stats.errors++;
 768                         continue;
 769                 }
 770
 771                 VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
 772
 773                 rx_pkts[nb_rx++] = rxm;
 774
 775                 rxvq->stats.bytes += rx_pkts[nb_rx - 1]->pkt_len;
 776                 virtio_update_packet_stats(&rxvq->stats, rxm);
 777         }
 778
 779         rxvq->stats.packets += nb_rx;
 780
 781         /* Allocate new mbuf for the used descriptor */
 782         error = ENOSPC;
 783         while (likely(!virtqueue_full(vq))) {
 784                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 785                 if (unlikely(new_mbuf == NULL)) {
 786                         struct rte_eth_dev *dev
 787                                 = &rte_eth_devices[rxvq->port_id];
 788                         dev->data->rx_mbuf_alloc_failed++;
 789                         break;
 790                 }
 791                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 792                 if (unlikely(error)) {
 793                         rte_pktmbuf_free(new_mbuf);
 794                         break;
 795                 }
 796                 nb_enqueued++;
 797         }
 798
 799         if (likely(nb_enqueued)) {
 800                 vq_update_avail_idx(vq);
 801
 802                 if (unlikely(virtqueue_kick_prepare(vq))) {
 803                         virtqueue_notify(vq);
 804                         PMD_RX_LOG(DEBUG, "Notified");
 805                 }
 806         }
 807
 808         return nb_rx;
 809 }
 810
 811 uint16_t
 812 virtio_recv_mergeable_pkts(void *rx_queue,
 813                         struct rte_mbuf **rx_pkts,
 814                         uint16_t nb_pkts)
 815 {
 816         struct virtnet_rx *rxvq = rx_queue;
 817         struct virtqueue *vq = rxvq->vq;
 818         struct virtio_hw *hw;
 819         struct rte_mbuf *rxm, *new_mbuf;
 820         uint16_t nb_used, num, nb_rx;
 821         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 822         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 823         struct rte_mbuf *prev;
 824         int error;
 825         uint32_t i, nb_enqueued;
 826         uint32_t seg_num;
 827         uint16_t extra_idx;
 828         uint32_t seg_res;
 829         uint32_t hdr_size;
 830         int offload;
 831
 832         nb_used = VIRTQUEUE_NUSED(vq);
 833
 834         virtio_rmb();
 835
 836         PMD_RX_LOG(DEBUG, "used:%d", nb_used);
 837
 838         hw = vq->hw;
 839         nb_rx = 0;
 840         i = 0;
 841         nb_enqueued = 0;
 842         seg_num = 0;
 843         extra_idx = 0;
 844         seg_res = 0;
 845         hdr_size = hw->vtnet_hdr_size;
 846         offload = rx_offload_enabled(hw);
 847
 848         while (i < nb_used) {
 849                 struct virtio_net_hdr_mrg_rxbuf *header;
 850
 851                 if (nb_rx == nb_pkts)
 852                         break;
 853
 854                 num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, 1);
 855                 if (num != 1)
 856                         continue;
 857
 858                 i++;
 859
 860                 PMD_RX_LOG(DEBUG, "dequeue:%d", num);
 861                 PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
 862
 863                 rxm = rcv_pkts[0];
 864
 865                 if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
 866                         PMD_RX_LOG(ERR, "Packet drop");
 867                         nb_enqueued++;
 868                         virtio_discard_rxbuf(vq, rxm);
 869                         rxvq->stats.errors++;
 870                         continue;
 871                 }
 872
 873                 header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
 874                         RTE_PKTMBUF_HEADROOM - hdr_size);
 875                 seg_num = header->num_buffers;
 876
 877                 if (seg_num == 0)
 878                         seg_num = 1;
 879
 880                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 881                 rxm->nb_segs = seg_num;
 882                 rxm->next = NULL;
 883                 rxm->ol_flags = 0;
 884                 rxm->vlan_tci = 0;
 885                 rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
 886                 rxm->data_len = (uint16_t)(len[0] - hdr_size);
 887
 888                 rxm->port = rxvq->port_id;
 889                 rx_pkts[nb_rx] = rxm;
 890                 prev = rxm;
 891
 892                 if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
 893                         virtio_discard_rxbuf(vq, rxm);
 894                         rxvq->stats.errors++;
 895                         continue;
 896                 }
 897
 898                 seg_res = seg_num - 1;
 899
 900                 while (seg_res != 0) {
 901                         /*
 902                          * Get extra segments for current uncompleted packet.
 903                          */
 904                         uint16_t  rcv_cnt =
 905                                 RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
 906                         if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
 907                                 uint32_t rx_num =
 908                                         virtqueue_dequeue_burst_rx(vq,
 909                                         rcv_pkts, len, rcv_cnt);
 910                                 i += rx_num;
 911                                 rcv_cnt = rx_num;
 912                         } else {
 913                                 PMD_RX_LOG(ERR,
 914                                            "No enough segments for packet.");
 915                                 nb_enqueued++;
 916                                 virtio_discard_rxbuf(vq, rxm);
 917                                 rxvq->stats.errors++;
 918                                 break;
 919                         }
 920
 921                         extra_idx = 0;
 922
 923                         while (extra_idx < rcv_cnt) {
 924                                 rxm = rcv_pkts[extra_idx];
 925
 926                                 rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
 927                                 rxm->next = NULL;
 928                                 rxm->pkt_len = (uint32_t)(len[extra_idx]);
 929                                 rxm->data_len = (uint16_t)(len[extra_idx]);
 930
 931                                 if (prev)
 932                                         prev->next = rxm;
 933
 934                                 prev = rxm;
 935                                 rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
 936                                 extra_idx++;
 937                         };
 938                         seg_res -= rcv_cnt;
 939                 }
 940
 941                 if (hw->vlan_strip)
 942                         rte_vlan_strip(rx_pkts[nb_rx]);
 943
 944                 VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
 945                         rx_pkts[nb_rx]->data_len);
 946
 947                 rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
 948                 virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
 949                 nb_rx++;
 950         }
 951
 952         rxvq->stats.packets += nb_rx;
 953
 954         /* Allocate new mbuf for the used descriptor */
 955         error = ENOSPC;
 956         while (likely(!virtqueue_full(vq))) {
 957                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 958                 if (unlikely(new_mbuf == NULL)) {
 959                         struct rte_eth_dev *dev
 960                                 = &rte_eth_devices[rxvq->port_id];
 961                         dev->data->rx_mbuf_alloc_failed++;
 962                         break;
 963                 }
 964                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 965                 if (unlikely(error)) {
 966                         rte_pktmbuf_free(new_mbuf);
 967                         break;
 968                 }
 969                 nb_enqueued++;
 970         }
 971
 972         if (likely(nb_enqueued)) {
 973                 vq_update_avail_idx(vq);
 974
 975                 if (unlikely(virtqueue_kick_prepare(vq))) {
 976                         virtqueue_notify(vq);
 977                         PMD_RX_LOG(DEBUG, "Notified");
 978                 }
 979         }
 980
 981         return nb_rx;
 982 }
 983
 984 uint16_t
 985 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 986 {
 987         struct virtnet_tx *txvq = tx_queue;
 988         struct virtqueue *vq = txvq->vq;
 989         struct virtio_hw *hw = vq->hw;
 990         uint16_t hdr_size = hw->vtnet_hdr_size;
 991         uint16_t nb_used, nb_tx;
 992         int error;
 993
 994         if (unlikely(nb_pkts < 1))
 995                 return nb_pkts;
 996
 997         PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
 998         nb_used = VIRTQUEUE_NUSED(vq);
 999
1000         virtio_rmb();
1001         if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
1002                 virtio_xmit_cleanup(vq, nb_used);
1003
1004         for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
1005                 struct rte_mbuf *txm = tx_pkts[nb_tx];
1006                 int can_push = 0, use_indirect = 0, slots, need;
1007
1008                 /* Do VLAN tag insertion */
1009                 if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
1010                         error = rte_vlan_insert(&txm);
1011                         if (unlikely(error)) {
1012                                 rte_pktmbuf_free(txm);
1013                                 continue;
1014                         }
1015                 }
1016
1017                 /* optimize ring usage */
1018                 if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
1019                       vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
1020                     rte_mbuf_refcnt_read(txm) == 1 &&
1021                     RTE_MBUF_DIRECT(txm) &&
1022                     txm->nb_segs == 1 &&
1023                     rte_pktmbuf_headroom(txm) >= hdr_size &&
1024                     rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
1025                                    __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
1026                         can_push = 1;
1027                 else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
1028                          txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
1029                         use_indirect = 1;
1030
1031                 /* How many main ring entries are needed to this Tx?
1032                  * any_layout => number of segments
1033                  * indirect   => 1
1034                  * default    => number of segments + 1
1035                  */
1036                 slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
1037                 need = slots - vq->vq_free_cnt;
1038
1039                 /* Positive value indicates it need free vring descriptors */
1040                 if (unlikely(need > 0)) {
1041                         nb_used = VIRTQUEUE_NUSED(vq);
1042                         virtio_rmb();
1043                         need = RTE_MIN(need, (int)nb_used);
1044
1045                         virtio_xmit_cleanup(vq, need);
1046                         need = slots - vq->vq_free_cnt;
1047                         if (unlikely(need > 0)) {
1048                                 PMD_TX_LOG(ERR,
1049                                            "No free tx descriptors to transmit");
1050                                 break;
1051                         }
1052                 }
1053
1054                 /* Enqueue Packet buffers */
1055                 virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
1056
1057                 txvq->stats.bytes += txm->pkt_len;
1058                 virtio_update_packet_stats(&txvq->stats, txm);
1059         }
1060
1061         txvq->stats.packets += nb_tx;
1062
1063         if (likely(nb_tx)) {
1064                 vq_update_avail_idx(vq);
1065
1066                 if (unlikely(virtqueue_kick_prepare(vq))) {
1067                         virtqueue_notify(vq);
1068                         PMD_TX_LOG(DEBUG, "Notified backend after xmit");
1069                 }
1070         }
1071
1072         return nb_tx;
1073 }