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_net.h>
  54 #include <rte_ip.h>
  55 #include <rte_udp.h>
  56 #include <rte_tcp.h>
  57
  58 #include "virtio_logs.h"
  59 #include "virtio_ethdev.h"
  60 #include "virtio_pci.h"
  61 #include "virtqueue.h"
  62 #include "virtio_rxtx.h"
  63
  64 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
  65 #define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
  66 #else
  67 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
  68 #endif
  69
  70
  71 #define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
  72         ETH_TXQ_FLAGS_NOOFFLOADS)
  73
  74 int
  75 virtio_dev_rx_queue_done(void *rxq, uint16_t offset)
  76 {
  77         struct virtnet_rx *rxvq = rxq;
  78         struct virtqueue *vq = rxvq->vq;
  79
  80         return VIRTQUEUE_NUSED(vq) >= offset;
  81 }
  82
  83 void
  84 vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
  85 {
  86         struct vring_desc *dp, *dp_tail;
  87         struct vq_desc_extra *dxp;
  88         uint16_t desc_idx_last = desc_idx;
  89
  90         dp  = &vq->vq_ring.desc[desc_idx];
  91         dxp = &vq->vq_descx[desc_idx];
  92         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
  93         if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
  94                 while (dp->flags & VRING_DESC_F_NEXT) {
  95                         desc_idx_last = dp->next;
  96                         dp = &vq->vq_ring.desc[dp->next];
  97                 }
  98         }
  99         dxp->ndescs = 0;
 100
 101         /*
 102          * We must append the existing free chain, if any, to the end of
 103          * newly freed chain. If the virtqueue was completely used, then
 104          * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
 105          */
 106         if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
 107                 vq->vq_desc_head_idx = desc_idx;
 108         } else {
 109                 dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
 110                 dp_tail->next = desc_idx;
 111         }
 112
 113         vq->vq_desc_tail_idx = desc_idx_last;
 114         dp->next = VQ_RING_DESC_CHAIN_END;
 115 }
 116
 117 static uint16_t
 118 virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
 119                            uint32_t *len, uint16_t num)
 120 {
 121         struct vring_used_elem *uep;
 122         struct rte_mbuf *cookie;
 123         uint16_t used_idx, desc_idx;
 124         uint16_t i;
 125
 126         /*  Caller does the check */
 127         for (i = 0; i < num ; i++) {
 128                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 129                 uep = &vq->vq_ring.used->ring[used_idx];
 130                 desc_idx = (uint16_t) uep->id;
 131                 len[i] = uep->len;
 132                 cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
 133
 134                 if (unlikely(cookie == NULL)) {
 135                         PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u",
 136                                 vq->vq_used_cons_idx);
 137                         break;
 138                 }
 139
 140                 rte_prefetch0(cookie);
 141                 rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
 142                 rx_pkts[i]  = cookie;
 143                 vq->vq_used_cons_idx++;
 144                 vq_ring_free_chain(vq, desc_idx);
 145                 vq->vq_descx[desc_idx].cookie = NULL;
 146         }
 147
 148         return i;
 149 }
 150
 151 #ifndef DEFAULT_TX_FREE_THRESH
 152 #define DEFAULT_TX_FREE_THRESH 32
 153 #endif
 154
 155 /* Cleanup from completed transmits. */
 156 static void
 157 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
 158 {
 159         uint16_t i, used_idx, desc_idx;
 160         for (i = 0; i < num; i++) {
 161                 struct vring_used_elem *uep;
 162                 struct vq_desc_extra *dxp;
 163
 164                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 165                 uep = &vq->vq_ring.used->ring[used_idx];
 166
 167                 desc_idx = (uint16_t) uep->id;
 168                 dxp = &vq->vq_descx[desc_idx];
 169                 vq->vq_used_cons_idx++;
 170                 vq_ring_free_chain(vq, desc_idx);
 171
 172                 if (dxp->cookie != NULL) {
 173                         rte_pktmbuf_free(dxp->cookie);
 174                         dxp->cookie = NULL;
 175                 }
 176         }
 177 }
 178
 179
 180 static inline int
 181 virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
 182 {
 183         struct vq_desc_extra *dxp;
 184         struct virtio_hw *hw = vq->hw;
 185         struct vring_desc *start_dp;
 186         uint16_t needed = 1;
 187         uint16_t head_idx, idx;
 188
 189         if (unlikely(vq->vq_free_cnt == 0))
 190                 return -ENOSPC;
 191         if (unlikely(vq->vq_free_cnt < needed))
 192                 return -EMSGSIZE;
 193
 194         head_idx = vq->vq_desc_head_idx;
 195         if (unlikely(head_idx >= vq->vq_nentries))
 196                 return -EFAULT;
 197
 198         idx = head_idx;
 199         dxp = &vq->vq_descx[idx];
 200         dxp->cookie = (void *)cookie;
 201         dxp->ndescs = needed;
 202
 203         start_dp = vq->vq_ring.desc;
 204         start_dp[idx].addr =
 205                 VIRTIO_MBUF_ADDR(cookie, vq) +
 206                 RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
 207         start_dp[idx].len =
 208                 cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 209         start_dp[idx].flags =  VRING_DESC_F_WRITE;
 210         idx = start_dp[idx].next;
 211         vq->vq_desc_head_idx = idx;
 212         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 213                 vq->vq_desc_tail_idx = idx;
 214         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 215         vq_update_avail_ring(vq, head_idx);
 216
 217         return 0;
 218 }
 219
 220 /* When doing TSO, the IP length is not included in the pseudo header
 221  * checksum of the packet given to the PMD, but for virtio it is
 222  * expected.
 223  */
 224 static void
 225 virtio_tso_fix_cksum(struct rte_mbuf *m)
 226 {
 227         /* common case: header is not fragmented */
 228         if (likely(rte_pktmbuf_data_len(m) >= m->l2_len + m->l3_len +
 229                         m->l4_len)) {
 230                 struct ipv4_hdr *iph;
 231                 struct ipv6_hdr *ip6h;
 232                 struct tcp_hdr *th;
 233                 uint16_t prev_cksum, new_cksum, ip_len, ip_paylen;
 234                 uint32_t tmp;
 235
 236                 iph = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *, m->l2_len);
 237                 th = RTE_PTR_ADD(iph, m->l3_len);
 238                 if ((iph->version_ihl >> 4) == 4) {
 239                         iph->hdr_checksum = 0;
 240                         iph->hdr_checksum = rte_ipv4_cksum(iph);
 241                         ip_len = iph->total_length;
 242                         ip_paylen = rte_cpu_to_be_16(rte_be_to_cpu_16(ip_len) -
 243                                 m->l3_len);
 244                 } else {
 245                         ip6h = (struct ipv6_hdr *)iph;
 246                         ip_paylen = ip6h->payload_len;
 247                 }
 248
 249                 /* calculate the new phdr checksum not including ip_paylen */
 250                 prev_cksum = th->cksum;
 251                 tmp = prev_cksum;
 252                 tmp += ip_paylen;
 253                 tmp = (tmp & 0xffff) + (tmp >> 16);
 254                 new_cksum = tmp;
 255
 256                 /* replace it in the packet */
 257                 th->cksum = new_cksum;
 258         }
 259 }
 260
 261 static inline int
 262 tx_offload_enabled(struct virtio_hw *hw)
 263 {
 264         return vtpci_with_feature(hw, VIRTIO_NET_F_CSUM) ||
 265                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO4) ||
 266                 vtpci_with_feature(hw, VIRTIO_NET_F_HOST_TSO6);
 267 }
 268
 269 /* avoid write operation when necessary, to lessen cache issues */
 270 #define ASSIGN_UNLESS_EQUAL(var, val) do {      \
 271         if ((var) != (val))                     \
 272                 (var) = (val);                  \
 273 } while (0)
 274
 275 static inline void
 276 virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
 277                        uint16_t needed, int use_indirect, int can_push)
 278 {
 279         struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
 280         struct vq_desc_extra *dxp;
 281         struct virtqueue *vq = txvq->vq;
 282         struct vring_desc *start_dp;
 283         uint16_t seg_num = cookie->nb_segs;
 284         uint16_t head_idx, idx;
 285         uint16_t head_size = vq->hw->vtnet_hdr_size;
 286         struct virtio_net_hdr *hdr;
 287         int offload;
 288
 289         offload = tx_offload_enabled(vq->hw);
 290         head_idx = vq->vq_desc_head_idx;
 291         idx = head_idx;
 292         dxp = &vq->vq_descx[idx];
 293         dxp->cookie = (void *)cookie;
 294         dxp->ndescs = needed;
 295
 296         start_dp = vq->vq_ring.desc;
 297
 298         if (can_push) {
 299                 /* prepend cannot fail, checked by caller */
 300                 hdr = (struct virtio_net_hdr *)
 301                         rte_pktmbuf_prepend(cookie, head_size);
 302                 /* rte_pktmbuf_prepend() counts the hdr size to the pkt length,
 303                  * which is wrong. Below subtract restores correct pkt size.
 304                  */
 305                 cookie->pkt_len -= head_size;
 306                 /* if offload disabled, it is not zeroed below, do it now */
 307                 if (offload == 0) {
 308                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 309                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 310                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 311                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 312                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 313                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 314                 }
 315         } else if (use_indirect) {
 316                 /* setup tx ring slot to point to indirect
 317                  * descriptor list stored in reserved region.
 318                  *
 319                  * the first slot in indirect ring is already preset
 320                  * to point to the header in reserved region
 321                  */
 322                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 323                         RTE_PTR_DIFF(&txr[idx].tx_indir, txr);
 324                 start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
 325                 start_dp[idx].flags = VRING_DESC_F_INDIRECT;
 326                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 327
 328                 /* loop below will fill in rest of the indirect elements */
 329                 start_dp = txr[idx].tx_indir;
 330                 idx = 1;
 331         } else {
 332                 /* setup first tx ring slot to point to header
 333                  * stored in reserved region.
 334                  */
 335                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 336                         RTE_PTR_DIFF(&txr[idx].tx_hdr, txr);
 337                 start_dp[idx].len   = vq->hw->vtnet_hdr_size;
 338                 start_dp[idx].flags = VRING_DESC_F_NEXT;
 339                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 340
 341                 idx = start_dp[idx].next;
 342         }
 343
 344         /* Checksum Offload / TSO */
 345         if (offload) {
 346                 if (cookie->ol_flags & PKT_TX_TCP_SEG)
 347                         cookie->ol_flags |= PKT_TX_TCP_CKSUM;
 348
 349                 switch (cookie->ol_flags & PKT_TX_L4_MASK) {
 350                 case PKT_TX_UDP_CKSUM:
 351                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 352                         hdr->csum_offset = offsetof(struct udp_hdr,
 353                                 dgram_cksum);
 354                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 355                         break;
 356
 357                 case PKT_TX_TCP_CKSUM:
 358                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 359                         hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
 360                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 361                         break;
 362
 363                 default:
 364                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 365                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 366                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 367                         break;
 368                 }
 369
 370                 /* TCP Segmentation Offload */
 371                 if (cookie->ol_flags & PKT_TX_TCP_SEG) {
 372                         virtio_tso_fix_cksum(cookie);
 373                         hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
 374                                 VIRTIO_NET_HDR_GSO_TCPV6 :
 375                                 VIRTIO_NET_HDR_GSO_TCPV4;
 376                         hdr->gso_size = cookie->tso_segsz;
 377                         hdr->hdr_len =
 378                                 cookie->l2_len +
 379                                 cookie->l3_len +
 380                                 cookie->l4_len;
 381                 } else {
 382                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 383                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 384                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 385                 }
 386         }
 387
 388         do {
 389                 start_dp[idx].addr  = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
 390                 start_dp[idx].len   = cookie->data_len;
 391                 start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
 392                 idx = start_dp[idx].next;
 393         } while ((cookie = cookie->next) != NULL);
 394
 395         if (use_indirect)
 396                 idx = vq->vq_ring.desc[head_idx].next;
 397
 398         vq->vq_desc_head_idx = idx;
 399         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 400                 vq->vq_desc_tail_idx = idx;
 401         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 402         vq_update_avail_ring(vq, head_idx);
 403 }
 404
 405 void
 406 virtio_dev_cq_start(struct rte_eth_dev *dev)
 407 {
 408         struct virtio_hw *hw = dev->data->dev_private;
 409
 410         if (hw->cvq && hw->cvq->vq) {
 411                 VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq->vq);
 412         }
 413 }
 414
 415 int
 416 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 417                         uint16_t queue_idx,
 418                         uint16_t nb_desc,
 419                         unsigned int socket_id __rte_unused,
 420                         __rte_unused const struct rte_eth_rxconf *rx_conf,
 421                         struct rte_mempool *mp)
 422 {
 423         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 424         struct virtio_hw *hw = dev->data->dev_private;
 425         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 426         struct virtnet_rx *rxvq;
 427
 428         PMD_INIT_FUNC_TRACE();
 429
 430         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 431                 nb_desc = vq->vq_nentries;
 432         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 433
 434         rxvq = &vq->rxq;
 435         rxvq->queue_id = queue_idx;
 436         rxvq->mpool = mp;
 437         if (rxvq->mpool == NULL) {
 438                 rte_exit(EXIT_FAILURE,
 439                         "Cannot allocate mbufs for rx virtqueue");
 440         }
 441         dev->data->rx_queues[queue_idx] = rxvq;
 442
 443         return 0;
 444 }
 445
 446 int
 447 virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev, uint16_t queue_idx)
 448 {
 449         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 450         struct virtio_hw *hw = dev->data->dev_private;
 451         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 452         struct virtnet_rx *rxvq = &vq->rxq;
 453         struct rte_mbuf *m;
 454         uint16_t desc_idx;
 455         int error, nbufs;
 456
 457         PMD_INIT_FUNC_TRACE();
 458
 459         /* Allocate blank mbufs for the each rx descriptor */
 460         nbufs = 0;
 461
 462         if (hw->use_simple_rx) {
 463                 for (desc_idx = 0; desc_idx < vq->vq_nentries;
 464                      desc_idx++) {
 465                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 466                         vq->vq_ring.desc[desc_idx].flags =
 467                                 VRING_DESC_F_WRITE;
 468                 }
 469         }
 470
 471         memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
 472         for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST;
 473              desc_idx++) {
 474                 vq->sw_ring[vq->vq_nentries + desc_idx] =
 475                         &rxvq->fake_mbuf;
 476         }
 477
 478         while (!virtqueue_full(vq)) {
 479                 m = rte_mbuf_raw_alloc(rxvq->mpool);
 480                 if (m == NULL)
 481                         break;
 482
 483                 /* Enqueue allocated buffers */
 484                 if (hw->use_simple_rx)
 485                         error = virtqueue_enqueue_recv_refill_simple(vq, m);
 486                 else
 487                         error = virtqueue_enqueue_recv_refill(vq, m);
 488
 489                 if (error) {
 490                         rte_pktmbuf_free(m);
 491                         break;
 492                 }
 493                 nbufs++;
 494         }
 495
 496         vq_update_avail_idx(vq);
 497
 498         PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
 499
 500         virtio_rxq_vec_setup(rxvq);
 501
 502         VIRTQUEUE_DUMP(vq);
 503
 504         return 0;
 505 }
 506
 507 /*
 508  * struct rte_eth_dev *dev: Used to update dev
 509  * uint16_t nb_desc: Defaults to values read from config space
 510  * unsigned int socket_id: Used to allocate memzone
 511  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
 512  * uint16_t queue_idx: Just used as an index in dev txq list
 513  */
 514 int
 515 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 516                         uint16_t queue_idx,
 517                         uint16_t nb_desc,
 518                         unsigned int socket_id __rte_unused,
 519                         const struct rte_eth_txconf *tx_conf)
 520 {
 521         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 522         struct virtio_hw *hw = dev->data->dev_private;
 523         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 524         struct virtnet_tx *txvq;
 525         uint16_t tx_free_thresh;
 526
 527         PMD_INIT_FUNC_TRACE();
 528
 529         /* cannot use simple rxtx funcs with multisegs or offloads */
 530         if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) != VIRTIO_SIMPLE_FLAGS)
 531                 hw->use_simple_tx = 0;
 532
 533         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 534                 nb_desc = vq->vq_nentries;
 535         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 536
 537         txvq = &vq->txq;
 538         txvq->queue_id = queue_idx;
 539
 540         tx_free_thresh = tx_conf->tx_free_thresh;
 541         if (tx_free_thresh == 0)
 542                 tx_free_thresh =
 543                         RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
 544
 545         if (tx_free_thresh >= (vq->vq_nentries - 3)) {
 546                 RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
 547                         "number of TX entries minus 3 (%u)."
 548                         " (tx_free_thresh=%u port=%u queue=%u)\n",
 549                         vq->vq_nentries - 3,
 550                         tx_free_thresh, dev->data->port_id, queue_idx);
 551                 return -EINVAL;
 552         }
 553
 554         vq->vq_free_thresh = tx_free_thresh;
 555
 556         dev->data->tx_queues[queue_idx] = txvq;
 557         return 0;
 558 }
 559
 560 int
 561 virtio_dev_tx_queue_setup_finish(struct rte_eth_dev *dev,
 562                                 uint16_t queue_idx)
 563 {
 564         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 565         struct virtio_hw *hw = dev->data->dev_private;
 566         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 567         uint16_t mid_idx = vq->vq_nentries >> 1;
 568         struct virtnet_tx *txvq = &vq->txq;
 569         uint16_t desc_idx;
 570
 571         PMD_INIT_FUNC_TRACE();
 572
 573         if (hw->use_simple_tx) {
 574                 for (desc_idx = 0; desc_idx < mid_idx; desc_idx++) {
 575                         vq->vq_ring.avail->ring[desc_idx] =
 576                                 desc_idx + mid_idx;
 577                         vq->vq_ring.desc[desc_idx + mid_idx].next =
 578                                 desc_idx;
 579                         vq->vq_ring.desc[desc_idx + mid_idx].addr =
 580                                 txvq->virtio_net_hdr_mem +
 581                                 offsetof(struct virtio_tx_region, tx_hdr);
 582                         vq->vq_ring.desc[desc_idx + mid_idx].len =
 583                                 vq->hw->vtnet_hdr_size;
 584                         vq->vq_ring.desc[desc_idx + mid_idx].flags =
 585                                 VRING_DESC_F_NEXT;
 586                         vq->vq_ring.desc[desc_idx].flags = 0;
 587                 }
 588                 for (desc_idx = mid_idx; desc_idx < vq->vq_nentries;
 589                      desc_idx++)
 590                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 591         }
 592
 593         VIRTQUEUE_DUMP(vq);
 594
 595         return 0;
 596 }
 597
 598 static void
 599 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
 600 {
 601         int error;
 602         /*
 603          * Requeue the discarded mbuf. This should always be
 604          * successful since it was just dequeued.
 605          */
 606         error = virtqueue_enqueue_recv_refill(vq, m);
 607         if (unlikely(error)) {
 608                 RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
 609                 rte_pktmbuf_free(m);
 610         }
 611 }
 612
 613 static void
 614 virtio_update_packet_stats(struct virtnet_stats *stats, struct rte_mbuf *mbuf)
 615 {
 616         uint32_t s = mbuf->pkt_len;
 617         struct ether_addr *ea;
 618
 619         if (s == 64) {
 620                 stats->size_bins[1]++;
 621         } else if (s > 64 && s < 1024) {
 622                 uint32_t bin;
 623
 624                 /* count zeros, and offset into correct bin */
 625                 bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
 626                 stats->size_bins[bin]++;
 627         } else {
 628                 if (s < 64)
 629                         stats->size_bins[0]++;
 630                 else if (s < 1519)
 631                         stats->size_bins[6]++;
 632                 else if (s >= 1519)
 633                         stats->size_bins[7]++;
 634         }
 635
 636         ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
 637         if (is_multicast_ether_addr(ea)) {
 638                 if (is_broadcast_ether_addr(ea))
 639                         stats->broadcast++;
 640                 else
 641                         stats->multicast++;
 642         }
 643 }
 644
 645 /* Optionally fill offload information in structure */
 646 static int
 647 virtio_rx_offload(struct rte_mbuf *m, struct virtio_net_hdr *hdr)
 648 {
 649         struct rte_net_hdr_lens hdr_lens;
 650         uint32_t hdrlen, ptype;
 651         int l4_supported = 0;
 652
 653         /* nothing to do */
 654         if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE)
 655                 return 0;
 656
 657         m->ol_flags |= PKT_RX_IP_CKSUM_UNKNOWN;
 658
 659         ptype = rte_net_get_ptype(m, &hdr_lens, RTE_PTYPE_ALL_MASK);
 660         m->packet_type = ptype;
 661         if ((ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_TCP ||
 662             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_UDP ||
 663             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_SCTP)
 664                 l4_supported = 1;
 665
 666         if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 667                 hdrlen = hdr_lens.l2_len + hdr_lens.l3_len + hdr_lens.l4_len;
 668                 if (hdr->csum_start <= hdrlen && l4_supported) {
 669                         m->ol_flags |= PKT_RX_L4_CKSUM_NONE;
 670                 } else {
 671                         /* Unknown proto or tunnel, do sw cksum. We can assume
 672                          * the cksum field is in the first segment since the
 673                          * buffers we provided to the host are large enough.
 674                          * In case of SCTP, this will be wrong since it's a CRC
 675                          * but there's nothing we can do.
 676                          */
 677                         uint16_t csum = 0, off;
 678
 679                         rte_raw_cksum_mbuf(m, hdr->csum_start,
 680                                 rte_pktmbuf_pkt_len(m) - hdr->csum_start,
 681                                 &csum);
 682                         if (likely(csum != 0xffff))
 683                                 csum = ~csum;
 684                         off = hdr->csum_offset + hdr->csum_start;
 685                         if (rte_pktmbuf_data_len(m) >= off + 1)
 686                                 *rte_pktmbuf_mtod_offset(m, uint16_t *,
 687                                         off) = csum;
 688                 }
 689         } else if (hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID && l4_supported) {
 690                 m->ol_flags |= PKT_RX_L4_CKSUM_GOOD;
 691         }
 692
 693         /* GSO request, save required information in mbuf */
 694         if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 695                 /* Check unsupported modes */
 696                 if ((hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) ||
 697                     (hdr->gso_size == 0)) {
 698                         return -EINVAL;
 699                 }
 700
 701                 /* Update mss lengthes in mbuf */
 702                 m->tso_segsz = hdr->gso_size;
 703                 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 704                         case VIRTIO_NET_HDR_GSO_TCPV4:
 705                         case VIRTIO_NET_HDR_GSO_TCPV6:
 706                                 m->ol_flags |= PKT_RX_LRO | \
 707                                         PKT_RX_L4_CKSUM_NONE;
 708                                 break;
 709                         default:
 710                                 return -EINVAL;
 711                 }
 712         }
 713
 714         return 0;
 715 }
 716
 717 static inline int
 718 rx_offload_enabled(struct virtio_hw *hw)
 719 {
 720         return vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_CSUM) ||
 721                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4) ||
 722                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO6);
 723 }
 724
 725 #define VIRTIO_MBUF_BURST_SZ 64
 726 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
 727 uint16_t
 728 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 729 {
 730         struct virtnet_rx *rxvq = rx_queue;
 731         struct virtqueue *vq = rxvq->vq;
 732         struct virtio_hw *hw = vq->hw;
 733         struct rte_mbuf *rxm, *new_mbuf;
 734         uint16_t nb_used, num, nb_rx;
 735         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 736         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 737         int error;
 738         uint32_t i, nb_enqueued;
 739         uint32_t hdr_size;
 740         int offload;
 741         struct virtio_net_hdr *hdr;
 742
 743         nb_rx = 0;
 744         if (unlikely(hw->started == 0))
 745                 return nb_rx;
 746
 747         nb_used = VIRTQUEUE_NUSED(vq);
 748
 749         virtio_rmb();
 750
 751         num = likely(nb_used <= nb_pkts) ? nb_used : nb_pkts;
 752         if (unlikely(num > VIRTIO_MBUF_BURST_SZ))
 753                 num = VIRTIO_MBUF_BURST_SZ;
 754         if (likely(num > DESC_PER_CACHELINE))
 755                 num = num - ((vq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
 756
 757         num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, num);
 758         PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
 759
 760         nb_enqueued = 0;
 761         hdr_size = hw->vtnet_hdr_size;
 762         offload = rx_offload_enabled(hw);
 763
 764         for (i = 0; i < num ; i++) {
 765                 rxm = rcv_pkts[i];
 766
 767                 PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
 768
 769                 if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
 770                         PMD_RX_LOG(ERR, "Packet drop");
 771                         nb_enqueued++;
 772                         virtio_discard_rxbuf(vq, rxm);
 773                         rxvq->stats.errors++;
 774                         continue;
 775                 }
 776
 777                 rxm->port = rxvq->port_id;
 778                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 779                 rxm->ol_flags = 0;
 780                 rxm->vlan_tci = 0;
 781
 782                 rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
 783                 rxm->data_len = (uint16_t)(len[i] - hdr_size);
 784
 785                 hdr = (struct virtio_net_hdr *)((char *)rxm->buf_addr +
 786                         RTE_PKTMBUF_HEADROOM - hdr_size);
 787
 788                 if (hw->vlan_strip)
 789                         rte_vlan_strip(rxm);
 790
 791                 if (offload && virtio_rx_offload(rxm, hdr) < 0) {
 792                         virtio_discard_rxbuf(vq, rxm);
 793                         rxvq->stats.errors++;
 794                         continue;
 795                 }
 796
 797                 VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
 798
 799                 rx_pkts[nb_rx++] = rxm;
 800
 801                 rxvq->stats.bytes += rxm->pkt_len;
 802                 virtio_update_packet_stats(&rxvq->stats, rxm);
 803         }
 804
 805         rxvq->stats.packets += nb_rx;
 806
 807         /* Allocate new mbuf for the used descriptor */
 808         error = ENOSPC;
 809         while (likely(!virtqueue_full(vq))) {
 810                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 811                 if (unlikely(new_mbuf == NULL)) {
 812                         struct rte_eth_dev *dev
 813                                 = &rte_eth_devices[rxvq->port_id];
 814                         dev->data->rx_mbuf_alloc_failed++;
 815                         break;
 816                 }
 817                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 818                 if (unlikely(error)) {
 819                         rte_pktmbuf_free(new_mbuf);
 820                         break;
 821                 }
 822                 nb_enqueued++;
 823         }
 824
 825         if (likely(nb_enqueued)) {
 826                 vq_update_avail_idx(vq);
 827
 828                 if (unlikely(virtqueue_kick_prepare(vq))) {
 829                         virtqueue_notify(vq);
 830                         PMD_RX_LOG(DEBUG, "Notified");
 831                 }
 832         }
 833
 834         return nb_rx;
 835 }
 836
 837 uint16_t
 838 virtio_recv_mergeable_pkts(void *rx_queue,
 839                         struct rte_mbuf **rx_pkts,
 840                         uint16_t nb_pkts)
 841 {
 842         struct virtnet_rx *rxvq = rx_queue;
 843         struct virtqueue *vq = rxvq->vq;
 844         struct virtio_hw *hw = vq->hw;
 845         struct rte_mbuf *rxm, *new_mbuf;
 846         uint16_t nb_used, num, nb_rx;
 847         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 848         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 849         struct rte_mbuf *prev;
 850         int error;
 851         uint32_t i, nb_enqueued;
 852         uint32_t seg_num;
 853         uint16_t extra_idx;
 854         uint32_t seg_res;
 855         uint32_t hdr_size;
 856         int offload;
 857
 858         nb_rx = 0;
 859         if (unlikely(hw->started == 0))
 860                 return nb_rx;
 861
 862         nb_used = VIRTQUEUE_NUSED(vq);
 863
 864         virtio_rmb();
 865
 866         PMD_RX_LOG(DEBUG, "used:%d", nb_used);
 867
 868         i = 0;
 869         nb_enqueued = 0;
 870         seg_num = 0;
 871         extra_idx = 0;
 872         seg_res = 0;
 873         hdr_size = hw->vtnet_hdr_size;
 874         offload = rx_offload_enabled(hw);
 875
 876         while (i < nb_used) {
 877                 struct virtio_net_hdr_mrg_rxbuf *header;
 878
 879                 if (nb_rx == nb_pkts)
 880                         break;
 881
 882                 num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, 1);
 883                 if (num != 1)
 884                         continue;
 885
 886                 i++;
 887
 888                 PMD_RX_LOG(DEBUG, "dequeue:%d", num);
 889                 PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
 890
 891                 rxm = rcv_pkts[0];
 892
 893                 if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
 894                         PMD_RX_LOG(ERR, "Packet drop");
 895                         nb_enqueued++;
 896                         virtio_discard_rxbuf(vq, rxm);
 897                         rxvq->stats.errors++;
 898                         continue;
 899                 }
 900
 901                 header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
 902                         RTE_PKTMBUF_HEADROOM - hdr_size);
 903                 seg_num = header->num_buffers;
 904
 905                 if (seg_num == 0)
 906                         seg_num = 1;
 907
 908                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 909                 rxm->nb_segs = seg_num;
 910                 rxm->ol_flags = 0;
 911                 rxm->vlan_tci = 0;
 912                 rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
 913                 rxm->data_len = (uint16_t)(len[0] - hdr_size);
 914
 915                 rxm->port = rxvq->port_id;
 916                 rx_pkts[nb_rx] = rxm;
 917                 prev = rxm;
 918
 919                 if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
 920                         virtio_discard_rxbuf(vq, rxm);
 921                         rxvq->stats.errors++;
 922                         continue;
 923                 }
 924
 925                 seg_res = seg_num - 1;
 926
 927                 while (seg_res != 0) {
 928                         /*
 929                          * Get extra segments for current uncompleted packet.
 930                          */
 931                         uint16_t  rcv_cnt =
 932                                 RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
 933                         if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
 934                                 uint32_t rx_num =
 935                                         virtqueue_dequeue_burst_rx(vq,
 936                                         rcv_pkts, len, rcv_cnt);
 937                                 i += rx_num;
 938                                 rcv_cnt = rx_num;
 939                         } else {
 940                                 PMD_RX_LOG(ERR,
 941                                            "No enough segments for packet.");
 942                                 nb_enqueued++;
 943                                 virtio_discard_rxbuf(vq, rxm);
 944                                 rxvq->stats.errors++;
 945                                 break;
 946                         }
 947
 948                         extra_idx = 0;
 949
 950                         while (extra_idx < rcv_cnt) {
 951                                 rxm = rcv_pkts[extra_idx];
 952
 953                                 rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
 954                                 rxm->pkt_len = (uint32_t)(len[extra_idx]);
 955                                 rxm->data_len = (uint16_t)(len[extra_idx]);
 956
 957                                 if (prev)
 958                                         prev->next = rxm;
 959
 960                                 prev = rxm;
 961                                 rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
 962                                 extra_idx++;
 963                         };
 964                         seg_res -= rcv_cnt;
 965                 }
 966
 967                 if (hw->vlan_strip)
 968                         rte_vlan_strip(rx_pkts[nb_rx]);
 969
 970                 VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
 971                         rx_pkts[nb_rx]->data_len);
 972
 973                 rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
 974                 virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
 975                 nb_rx++;
 976         }
 977
 978         rxvq->stats.packets += nb_rx;
 979
 980         /* Allocate new mbuf for the used descriptor */
 981         error = ENOSPC;
 982         while (likely(!virtqueue_full(vq))) {
 983                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 984                 if (unlikely(new_mbuf == NULL)) {
 985                         struct rte_eth_dev *dev
 986                                 = &rte_eth_devices[rxvq->port_id];
 987                         dev->data->rx_mbuf_alloc_failed++;
 988                         break;
 989                 }
 990                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 991                 if (unlikely(error)) {
 992                         rte_pktmbuf_free(new_mbuf);
 993                         break;
 994                 }
 995                 nb_enqueued++;
 996         }
 997
 998         if (likely(nb_enqueued)) {
 999                 vq_update_avail_idx(vq);
1000
1001                 if (unlikely(virtqueue_kick_prepare(vq))) {
1002                         virtqueue_notify(vq);
1003                         PMD_RX_LOG(DEBUG, "Notified");
1004                 }
1005         }
1006
1007         return nb_rx;
1008 }
1009
1010 uint16_t
1011 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
1012 {
1013         struct virtnet_tx *txvq = tx_queue;
1014         struct virtqueue *vq = txvq->vq;
1015         struct virtio_hw *hw = vq->hw;
1016         uint16_t hdr_size = hw->vtnet_hdr_size;
1017         uint16_t nb_used, nb_tx = 0;
1018         int error;
1019
1020         if (unlikely(hw->started == 0))
1021                 return nb_tx;
1022
1023         if (unlikely(nb_pkts < 1))
1024                 return nb_pkts;
1025
1026         PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
1027         nb_used = VIRTQUEUE_NUSED(vq);
1028
1029         virtio_rmb();
1030         if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
1031                 virtio_xmit_cleanup(vq, nb_used);
1032
1033         for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
1034                 struct rte_mbuf *txm = tx_pkts[nb_tx];
1035                 int can_push = 0, use_indirect = 0, slots, need;
1036
1037                 /* Do VLAN tag insertion */
1038                 if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
1039                         error = rte_vlan_insert(&txm);
1040                         if (unlikely(error)) {
1041                                 rte_pktmbuf_free(txm);
1042                                 continue;
1043                         }
1044                 }
1045
1046                 /* optimize ring usage */
1047                 if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
1048                       vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
1049                     rte_mbuf_refcnt_read(txm) == 1 &&
1050                     RTE_MBUF_DIRECT(txm) &&
1051                     txm->nb_segs == 1 &&
1052                     rte_pktmbuf_headroom(txm) >= hdr_size &&
1053                     rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
1054                                    __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
1055                         can_push = 1;
1056                 else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
1057                          txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
1058                         use_indirect = 1;
1059
1060                 /* How many main ring entries are needed to this Tx?
1061                  * any_layout => number of segments
1062                  * indirect   => 1
1063                  * default    => number of segments + 1
1064                  */
1065                 slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
1066                 need = slots - vq->vq_free_cnt;
1067
1068                 /* Positive value indicates it need free vring descriptors */
1069                 if (unlikely(need > 0)) {
1070                         nb_used = VIRTQUEUE_NUSED(vq);
1071                         virtio_rmb();
1072                         need = RTE_MIN(need, (int)nb_used);
1073
1074                         virtio_xmit_cleanup(vq, need);
1075                         need = slots - vq->vq_free_cnt;
1076                         if (unlikely(need > 0)) {
1077                                 PMD_TX_LOG(ERR,
1078                                            "No free tx descriptors to transmit");
1079                                 break;
1080                         }
1081                 }
1082
1083                 /* Enqueue Packet buffers */
1084                 virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
1085
1086                 txvq->stats.bytes += txm->pkt_len;
1087                 virtio_update_packet_stats(&txvq->stats, txm);
1088         }
1089
1090         txvq->stats.packets += nb_tx;
1091
1092         if (likely(nb_tx)) {
1093                 vq_update_avail_idx(vq);
1094
1095                 if (unlikely(virtqueue_kick_prepare(vq))) {
1096                         virtqueue_notify(vq);
1097                         PMD_TX_LOG(DEBUG, "Notified backend after xmit");
1098                 }
1099         }
1100
1101         return nb_tx;
1102 }