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 static 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                 /* if offload disabled, it is not zeroed below, do it now */
 303                 if (offload == 0) {
 304                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 305                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 306                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 307                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 308                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 309                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 310                 }
 311         } else if (use_indirect) {
 312                 /* setup tx ring slot to point to indirect
 313                  * descriptor list stored in reserved region.
 314                  *
 315                  * the first slot in indirect ring is already preset
 316                  * to point to the header in reserved region
 317                  */
 318                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 319                         RTE_PTR_DIFF(&txr[idx].tx_indir, txr);
 320                 start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
 321                 start_dp[idx].flags = VRING_DESC_F_INDIRECT;
 322                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 323
 324                 /* loop below will fill in rest of the indirect elements */
 325                 start_dp = txr[idx].tx_indir;
 326                 idx = 1;
 327         } else {
 328                 /* setup first tx ring slot to point to header
 329                  * stored in reserved region.
 330                  */
 331                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem +
 332                         RTE_PTR_DIFF(&txr[idx].tx_hdr, txr);
 333                 start_dp[idx].len   = vq->hw->vtnet_hdr_size;
 334                 start_dp[idx].flags = VRING_DESC_F_NEXT;
 335                 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr;
 336
 337                 idx = start_dp[idx].next;
 338         }
 339
 340         /* Checksum Offload / TSO */
 341         if (offload) {
 342                 if (cookie->ol_flags & PKT_TX_TCP_SEG)
 343                         cookie->ol_flags |= PKT_TX_TCP_CKSUM;
 344
 345                 switch (cookie->ol_flags & PKT_TX_L4_MASK) {
 346                 case PKT_TX_UDP_CKSUM:
 347                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 348                         hdr->csum_offset = offsetof(struct udp_hdr,
 349                                 dgram_cksum);
 350                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 351                         break;
 352
 353                 case PKT_TX_TCP_CKSUM:
 354                         hdr->csum_start = cookie->l2_len + cookie->l3_len;
 355                         hdr->csum_offset = offsetof(struct tcp_hdr, cksum);
 356                         hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 357                         break;
 358
 359                 default:
 360                         ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0);
 361                         ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0);
 362                         ASSIGN_UNLESS_EQUAL(hdr->flags, 0);
 363                         break;
 364                 }
 365
 366                 /* TCP Segmentation Offload */
 367                 if (cookie->ol_flags & PKT_TX_TCP_SEG) {
 368                         virtio_tso_fix_cksum(cookie);
 369                         hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ?
 370                                 VIRTIO_NET_HDR_GSO_TCPV6 :
 371                                 VIRTIO_NET_HDR_GSO_TCPV4;
 372                         hdr->gso_size = cookie->tso_segsz;
 373                         hdr->hdr_len =
 374                                 cookie->l2_len +
 375                                 cookie->l3_len +
 376                                 cookie->l4_len;
 377                 } else {
 378                         ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0);
 379                         ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0);
 380                         ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0);
 381                 }
 382         }
 383
 384         do {
 385                 start_dp[idx].addr  = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
 386                 start_dp[idx].len   = cookie->data_len;
 387                 start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
 388                 idx = start_dp[idx].next;
 389         } while ((cookie = cookie->next) != NULL);
 390
 391         if (use_indirect)
 392                 idx = vq->vq_ring.desc[head_idx].next;
 393
 394         vq->vq_desc_head_idx = idx;
 395         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 396                 vq->vq_desc_tail_idx = idx;
 397         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 398         vq_update_avail_ring(vq, head_idx);
 399 }
 400
 401 void
 402 virtio_dev_cq_start(struct rte_eth_dev *dev)
 403 {
 404         struct virtio_hw *hw = dev->data->dev_private;
 405
 406         if (hw->cvq && hw->cvq->vq) {
 407                 VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq->vq);
 408         }
 409 }
 410
 411 int
 412 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 413                         uint16_t queue_idx,
 414                         uint16_t nb_desc,
 415                         unsigned int socket_id __rte_unused,
 416                         __rte_unused const struct rte_eth_rxconf *rx_conf,
 417                         struct rte_mempool *mp)
 418 {
 419         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 420         struct virtio_hw *hw = dev->data->dev_private;
 421         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 422         struct virtnet_rx *rxvq;
 423
 424         PMD_INIT_FUNC_TRACE();
 425
 426         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 427                 nb_desc = vq->vq_nentries;
 428         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 429
 430         rxvq = &vq->rxq;
 431         rxvq->queue_id = queue_idx;
 432         rxvq->mpool = mp;
 433         if (rxvq->mpool == NULL) {
 434                 rte_exit(EXIT_FAILURE,
 435                         "Cannot allocate mbufs for rx virtqueue");
 436         }
 437         dev->data->rx_queues[queue_idx] = rxvq;
 438
 439         return 0;
 440 }
 441
 442 int
 443 virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev, uint16_t queue_idx)
 444 {
 445         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 446         struct virtio_hw *hw = dev->data->dev_private;
 447         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 448         struct virtnet_rx *rxvq = &vq->rxq;
 449         struct rte_mbuf *m;
 450         uint16_t desc_idx;
 451         int error, nbufs;
 452
 453         PMD_INIT_FUNC_TRACE();
 454
 455         /* Allocate blank mbufs for the each rx descriptor */
 456         nbufs = 0;
 457
 458         if (hw->use_simple_rxtx) {
 459                 for (desc_idx = 0; desc_idx < vq->vq_nentries;
 460                      desc_idx++) {
 461                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 462                         vq->vq_ring.desc[desc_idx].flags =
 463                                 VRING_DESC_F_WRITE;
 464                 }
 465         }
 466
 467         memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
 468         for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST;
 469              desc_idx++) {
 470                 vq->sw_ring[vq->vq_nentries + desc_idx] =
 471                         &rxvq->fake_mbuf;
 472         }
 473
 474         while (!virtqueue_full(vq)) {
 475                 m = rte_mbuf_raw_alloc(rxvq->mpool);
 476                 if (m == NULL)
 477                         break;
 478
 479                 /* Enqueue allocated buffers */
 480                 if (hw->use_simple_rxtx)
 481                         error = virtqueue_enqueue_recv_refill_simple(vq, m);
 482                 else
 483                         error = virtqueue_enqueue_recv_refill(vq, m);
 484
 485                 if (error) {
 486                         rte_pktmbuf_free(m);
 487                         break;
 488                 }
 489                 nbufs++;
 490         }
 491
 492         vq_update_avail_idx(vq);
 493
 494         PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
 495
 496         virtio_rxq_vec_setup(rxvq);
 497
 498         VIRTQUEUE_DUMP(vq);
 499
 500         return 0;
 501 }
 502
 503 /*
 504  * struct rte_eth_dev *dev: Used to update dev
 505  * uint16_t nb_desc: Defaults to values read from config space
 506  * unsigned int socket_id: Used to allocate memzone
 507  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
 508  * uint16_t queue_idx: Just used as an index in dev txq list
 509  */
 510 int
 511 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 512                         uint16_t queue_idx,
 513                         uint16_t nb_desc,
 514                         unsigned int socket_id __rte_unused,
 515                         const struct rte_eth_txconf *tx_conf)
 516 {
 517         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 518         struct virtio_hw *hw = dev->data->dev_private;
 519         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 520         struct virtnet_tx *txvq;
 521         uint16_t tx_free_thresh;
 522
 523         PMD_INIT_FUNC_TRACE();
 524
 525         /* cannot use simple rxtx funcs with multisegs or offloads */
 526         if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) != VIRTIO_SIMPLE_FLAGS)
 527                 hw->use_simple_rxtx = 0;
 528
 529         if (nb_desc == 0 || nb_desc > vq->vq_nentries)
 530                 nb_desc = vq->vq_nentries;
 531         vq->vq_free_cnt = RTE_MIN(vq->vq_free_cnt, nb_desc);
 532
 533         txvq = &vq->txq;
 534         txvq->queue_id = queue_idx;
 535
 536         tx_free_thresh = tx_conf->tx_free_thresh;
 537         if (tx_free_thresh == 0)
 538                 tx_free_thresh =
 539                         RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
 540
 541         if (tx_free_thresh >= (vq->vq_nentries - 3)) {
 542                 RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
 543                         "number of TX entries minus 3 (%u)."
 544                         " (tx_free_thresh=%u port=%u queue=%u)\n",
 545                         vq->vq_nentries - 3,
 546                         tx_free_thresh, dev->data->port_id, queue_idx);
 547                 return -EINVAL;
 548         }
 549
 550         vq->vq_free_thresh = tx_free_thresh;
 551
 552         dev->data->tx_queues[queue_idx] = txvq;
 553         return 0;
 554 }
 555
 556 int
 557 virtio_dev_tx_queue_setup_finish(struct rte_eth_dev *dev,
 558                                 uint16_t queue_idx)
 559 {
 560         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 561         struct virtio_hw *hw = dev->data->dev_private;
 562         struct virtqueue *vq = hw->vqs[vtpci_queue_idx];
 563         uint16_t mid_idx = vq->vq_nentries >> 1;
 564         struct virtnet_tx *txvq = &vq->txq;
 565         uint16_t desc_idx;
 566
 567         PMD_INIT_FUNC_TRACE();
 568
 569         if (hw->use_simple_rxtx) {
 570                 for (desc_idx = 0; desc_idx < mid_idx; desc_idx++) {
 571                         vq->vq_ring.avail->ring[desc_idx] =
 572                                 desc_idx + mid_idx;
 573                         vq->vq_ring.desc[desc_idx + mid_idx].next =
 574                                 desc_idx;
 575                         vq->vq_ring.desc[desc_idx + mid_idx].addr =
 576                                 txvq->virtio_net_hdr_mem +
 577                                 offsetof(struct virtio_tx_region, tx_hdr);
 578                         vq->vq_ring.desc[desc_idx + mid_idx].len =
 579                                 vq->hw->vtnet_hdr_size;
 580                         vq->vq_ring.desc[desc_idx + mid_idx].flags =
 581                                 VRING_DESC_F_NEXT;
 582                         vq->vq_ring.desc[desc_idx].flags = 0;
 583                 }
 584                 for (desc_idx = mid_idx; desc_idx < vq->vq_nentries;
 585                      desc_idx++)
 586                         vq->vq_ring.avail->ring[desc_idx] = desc_idx;
 587         }
 588
 589         VIRTQUEUE_DUMP(vq);
 590
 591         return 0;
 592 }
 593
 594 static void
 595 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
 596 {
 597         int error;
 598         /*
 599          * Requeue the discarded mbuf. This should always be
 600          * successful since it was just dequeued.
 601          */
 602         error = virtqueue_enqueue_recv_refill(vq, m);
 603         if (unlikely(error)) {
 604                 RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
 605                 rte_pktmbuf_free(m);
 606         }
 607 }
 608
 609 static void
 610 virtio_update_packet_stats(struct virtnet_stats *stats, struct rte_mbuf *mbuf)
 611 {
 612         uint32_t s = mbuf->pkt_len;
 613         struct ether_addr *ea;
 614
 615         if (s == 64) {
 616                 stats->size_bins[1]++;
 617         } else if (s > 64 && s < 1024) {
 618                 uint32_t bin;
 619
 620                 /* count zeros, and offset into correct bin */
 621                 bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
 622                 stats->size_bins[bin]++;
 623         } else {
 624                 if (s < 64)
 625                         stats->size_bins[0]++;
 626                 else if (s < 1519)
 627                         stats->size_bins[6]++;
 628                 else if (s >= 1519)
 629                         stats->size_bins[7]++;
 630         }
 631
 632         ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
 633         if (is_multicast_ether_addr(ea)) {
 634                 if (is_broadcast_ether_addr(ea))
 635                         stats->broadcast++;
 636                 else
 637                         stats->multicast++;
 638         }
 639 }
 640
 641 /* Optionally fill offload information in structure */
 642 static int
 643 virtio_rx_offload(struct rte_mbuf *m, struct virtio_net_hdr *hdr)
 644 {
 645         struct rte_net_hdr_lens hdr_lens;
 646         uint32_t hdrlen, ptype;
 647         int l4_supported = 0;
 648
 649         /* nothing to do */
 650         if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE)
 651                 return 0;
 652
 653         m->ol_flags |= PKT_RX_IP_CKSUM_UNKNOWN;
 654
 655         ptype = rte_net_get_ptype(m, &hdr_lens, RTE_PTYPE_ALL_MASK);
 656         m->packet_type = ptype;
 657         if ((ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_TCP ||
 658             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_UDP ||
 659             (ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_SCTP)
 660                 l4_supported = 1;
 661
 662         if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 663                 hdrlen = hdr_lens.l2_len + hdr_lens.l3_len + hdr_lens.l4_len;
 664                 if (hdr->csum_start <= hdrlen && l4_supported) {
 665                         m->ol_flags |= PKT_RX_L4_CKSUM_NONE;
 666                 } else {
 667                         /* Unknown proto or tunnel, do sw cksum. We can assume
 668                          * the cksum field is in the first segment since the
 669                          * buffers we provided to the host are large enough.
 670                          * In case of SCTP, this will be wrong since it's a CRC
 671                          * but there's nothing we can do.
 672                          */
 673                         uint16_t csum, off;
 674
 675                         rte_raw_cksum_mbuf(m, hdr->csum_start,
 676                                 rte_pktmbuf_pkt_len(m) - hdr->csum_start,
 677                                 &csum);
 678                         if (likely(csum != 0xffff))
 679                                 csum = ~csum;
 680                         off = hdr->csum_offset + hdr->csum_start;
 681                         if (rte_pktmbuf_data_len(m) >= off + 1)
 682                                 *rte_pktmbuf_mtod_offset(m, uint16_t *,
 683                                         off) = csum;
 684                 }
 685         } else if (hdr->flags & VIRTIO_NET_HDR_F_DATA_VALID && l4_supported) {
 686                 m->ol_flags |= PKT_RX_L4_CKSUM_GOOD;
 687         }
 688
 689         /* GSO request, save required information in mbuf */
 690         if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 691                 /* Check unsupported modes */
 692                 if ((hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) ||
 693                     (hdr->gso_size == 0)) {
 694                         return -EINVAL;
 695                 }
 696
 697                 /* Update mss lengthes in mbuf */
 698                 m->tso_segsz = hdr->gso_size;
 699                 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 700                         case VIRTIO_NET_HDR_GSO_TCPV4:
 701                         case VIRTIO_NET_HDR_GSO_TCPV6:
 702                                 m->ol_flags |= PKT_RX_LRO | \
 703                                         PKT_RX_L4_CKSUM_NONE;
 704                                 break;
 705                         default:
 706                                 return -EINVAL;
 707                 }
 708         }
 709
 710         return 0;
 711 }
 712
 713 static inline int
 714 rx_offload_enabled(struct virtio_hw *hw)
 715 {
 716         return vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_CSUM) ||
 717                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO4) ||
 718                 vtpci_with_feature(hw, VIRTIO_NET_F_GUEST_TSO6);
 719 }
 720
 721 #define VIRTIO_MBUF_BURST_SZ 64
 722 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
 723 uint16_t
 724 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 725 {
 726         struct virtnet_rx *rxvq = rx_queue;
 727         struct virtqueue *vq = rxvq->vq;
 728         struct virtio_hw *hw = vq->hw;
 729         struct rte_mbuf *rxm, *new_mbuf;
 730         uint16_t nb_used, num, nb_rx;
 731         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 732         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 733         int error;
 734         uint32_t i, nb_enqueued;
 735         uint32_t hdr_size;
 736         int offload;
 737         struct virtio_net_hdr *hdr;
 738
 739         nb_rx = 0;
 740         if (unlikely(hw->started == 0))
 741                 return nb_rx;
 742
 743         nb_used = VIRTQUEUE_NUSED(vq);
 744
 745         virtio_rmb();
 746
 747         num = likely(nb_used <= nb_pkts) ? nb_used : nb_pkts;
 748         if (unlikely(num > VIRTIO_MBUF_BURST_SZ))
 749                 num = VIRTIO_MBUF_BURST_SZ;
 750         if (likely(num > DESC_PER_CACHELINE))
 751                 num = num - ((vq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
 752
 753         num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, num);
 754         PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
 755
 756         nb_enqueued = 0;
 757         hdr_size = hw->vtnet_hdr_size;
 758         offload = rx_offload_enabled(hw);
 759
 760         for (i = 0; i < num ; i++) {
 761                 rxm = rcv_pkts[i];
 762
 763                 PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
 764
 765                 if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
 766                         PMD_RX_LOG(ERR, "Packet drop");
 767                         nb_enqueued++;
 768                         virtio_discard_rxbuf(vq, rxm);
 769                         rxvq->stats.errors++;
 770                         continue;
 771                 }
 772
 773                 rxm->port = rxvq->port_id;
 774                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 775                 rxm->ol_flags = 0;
 776                 rxm->vlan_tci = 0;
 777
 778                 rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
 779                 rxm->data_len = (uint16_t)(len[i] - hdr_size);
 780
 781                 hdr = (struct virtio_net_hdr *)((char *)rxm->buf_addr +
 782                         RTE_PKTMBUF_HEADROOM - hdr_size);
 783
 784                 if (hw->vlan_strip)
 785                         rte_vlan_strip(rxm);
 786
 787                 if (offload && virtio_rx_offload(rxm, hdr) < 0) {
 788                         virtio_discard_rxbuf(vq, rxm);
 789                         rxvq->stats.errors++;
 790                         continue;
 791                 }
 792
 793                 VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
 794
 795                 rx_pkts[nb_rx++] = rxm;
 796
 797                 rxvq->stats.bytes += rxm->pkt_len;
 798                 virtio_update_packet_stats(&rxvq->stats, rxm);
 799         }
 800
 801         rxvq->stats.packets += nb_rx;
 802
 803         /* Allocate new mbuf for the used descriptor */
 804         error = ENOSPC;
 805         while (likely(!virtqueue_full(vq))) {
 806                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 807                 if (unlikely(new_mbuf == NULL)) {
 808                         struct rte_eth_dev *dev
 809                                 = &rte_eth_devices[rxvq->port_id];
 810                         dev->data->rx_mbuf_alloc_failed++;
 811                         break;
 812                 }
 813                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 814                 if (unlikely(error)) {
 815                         rte_pktmbuf_free(new_mbuf);
 816                         break;
 817                 }
 818                 nb_enqueued++;
 819         }
 820
 821         if (likely(nb_enqueued)) {
 822                 vq_update_avail_idx(vq);
 823
 824                 if (unlikely(virtqueue_kick_prepare(vq))) {
 825                         virtqueue_notify(vq);
 826                         PMD_RX_LOG(DEBUG, "Notified");
 827                 }
 828         }
 829
 830         return nb_rx;
 831 }
 832
 833 uint16_t
 834 virtio_recv_mergeable_pkts(void *rx_queue,
 835                         struct rte_mbuf **rx_pkts,
 836                         uint16_t nb_pkts)
 837 {
 838         struct virtnet_rx *rxvq = rx_queue;
 839         struct virtqueue *vq = rxvq->vq;
 840         struct virtio_hw *hw = vq->hw;
 841         struct rte_mbuf *rxm, *new_mbuf;
 842         uint16_t nb_used, num, nb_rx;
 843         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 844         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 845         struct rte_mbuf *prev;
 846         int error;
 847         uint32_t i, nb_enqueued;
 848         uint32_t seg_num;
 849         uint16_t extra_idx;
 850         uint32_t seg_res;
 851         uint32_t hdr_size;
 852         int offload;
 853
 854         nb_rx = 0;
 855         if (unlikely(hw->started == 0))
 856                 return nb_rx;
 857
 858         nb_used = VIRTQUEUE_NUSED(vq);
 859
 860         virtio_rmb();
 861
 862         PMD_RX_LOG(DEBUG, "used:%d", nb_used);
 863
 864         i = 0;
 865         nb_enqueued = 0;
 866         seg_num = 0;
 867         extra_idx = 0;
 868         seg_res = 0;
 869         hdr_size = hw->vtnet_hdr_size;
 870         offload = rx_offload_enabled(hw);
 871
 872         while (i < nb_used) {
 873                 struct virtio_net_hdr_mrg_rxbuf *header;
 874
 875                 if (nb_rx == nb_pkts)
 876                         break;
 877
 878                 num = virtqueue_dequeue_burst_rx(vq, rcv_pkts, len, 1);
 879                 if (num != 1)
 880                         continue;
 881
 882                 i++;
 883
 884                 PMD_RX_LOG(DEBUG, "dequeue:%d", num);
 885                 PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
 886
 887                 rxm = rcv_pkts[0];
 888
 889                 if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
 890                         PMD_RX_LOG(ERR, "Packet drop");
 891                         nb_enqueued++;
 892                         virtio_discard_rxbuf(vq, rxm);
 893                         rxvq->stats.errors++;
 894                         continue;
 895                 }
 896
 897                 header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
 898                         RTE_PKTMBUF_HEADROOM - hdr_size);
 899                 seg_num = header->num_buffers;
 900
 901                 if (seg_num == 0)
 902                         seg_num = 1;
 903
 904                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 905                 rxm->nb_segs = seg_num;
 906                 rxm->ol_flags = 0;
 907                 rxm->vlan_tci = 0;
 908                 rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
 909                 rxm->data_len = (uint16_t)(len[0] - hdr_size);
 910
 911                 rxm->port = rxvq->port_id;
 912                 rx_pkts[nb_rx] = rxm;
 913                 prev = rxm;
 914
 915                 if (offload && virtio_rx_offload(rxm, &header->hdr) < 0) {
 916                         virtio_discard_rxbuf(vq, rxm);
 917                         rxvq->stats.errors++;
 918                         continue;
 919                 }
 920
 921                 seg_res = seg_num - 1;
 922
 923                 while (seg_res != 0) {
 924                         /*
 925                          * Get extra segments for current uncompleted packet.
 926                          */
 927                         uint16_t  rcv_cnt =
 928                                 RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
 929                         if (likely(VIRTQUEUE_NUSED(vq) >= rcv_cnt)) {
 930                                 uint32_t rx_num =
 931                                         virtqueue_dequeue_burst_rx(vq,
 932                                         rcv_pkts, len, rcv_cnt);
 933                                 i += rx_num;
 934                                 rcv_cnt = rx_num;
 935                         } else {
 936                                 PMD_RX_LOG(ERR,
 937                                            "No enough segments for packet.");
 938                                 nb_enqueued++;
 939                                 virtio_discard_rxbuf(vq, rxm);
 940                                 rxvq->stats.errors++;
 941                                 break;
 942                         }
 943
 944                         extra_idx = 0;
 945
 946                         while (extra_idx < rcv_cnt) {
 947                                 rxm = rcv_pkts[extra_idx];
 948
 949                                 rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
 950                                 rxm->pkt_len = (uint32_t)(len[extra_idx]);
 951                                 rxm->data_len = (uint16_t)(len[extra_idx]);
 952
 953                                 if (prev)
 954                                         prev->next = rxm;
 955
 956                                 prev = rxm;
 957                                 rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
 958                                 extra_idx++;
 959                         };
 960                         seg_res -= rcv_cnt;
 961                 }
 962
 963                 if (hw->vlan_strip)
 964                         rte_vlan_strip(rx_pkts[nb_rx]);
 965
 966                 VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
 967                         rx_pkts[nb_rx]->data_len);
 968
 969                 rxvq->stats.bytes += rx_pkts[nb_rx]->pkt_len;
 970                 virtio_update_packet_stats(&rxvq->stats, rx_pkts[nb_rx]);
 971                 nb_rx++;
 972         }
 973
 974         rxvq->stats.packets += nb_rx;
 975
 976         /* Allocate new mbuf for the used descriptor */
 977         error = ENOSPC;
 978         while (likely(!virtqueue_full(vq))) {
 979                 new_mbuf = rte_mbuf_raw_alloc(rxvq->mpool);
 980                 if (unlikely(new_mbuf == NULL)) {
 981                         struct rte_eth_dev *dev
 982                                 = &rte_eth_devices[rxvq->port_id];
 983                         dev->data->rx_mbuf_alloc_failed++;
 984                         break;
 985                 }
 986                 error = virtqueue_enqueue_recv_refill(vq, new_mbuf);
 987                 if (unlikely(error)) {
 988                         rte_pktmbuf_free(new_mbuf);
 989                         break;
 990                 }
 991                 nb_enqueued++;
 992         }
 993
 994         if (likely(nb_enqueued)) {
 995                 vq_update_avail_idx(vq);
 996
 997                 if (unlikely(virtqueue_kick_prepare(vq))) {
 998                         virtqueue_notify(vq);
 999                         PMD_RX_LOG(DEBUG, "Notified");
1000                 }
1001         }
1002
1003         return nb_rx;
1004 }
1005
1006 uint16_t
1007 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
1008 {
1009         struct virtnet_tx *txvq = tx_queue;
1010         struct virtqueue *vq = txvq->vq;
1011         struct virtio_hw *hw = vq->hw;
1012         uint16_t hdr_size = hw->vtnet_hdr_size;
1013         uint16_t nb_used, nb_tx = 0;
1014         int error;
1015
1016         if (unlikely(hw->started == 0))
1017                 return nb_tx;
1018
1019         if (unlikely(nb_pkts < 1))
1020                 return nb_pkts;
1021
1022         PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
1023         nb_used = VIRTQUEUE_NUSED(vq);
1024
1025         virtio_rmb();
1026         if (likely(nb_used > vq->vq_nentries - vq->vq_free_thresh))
1027                 virtio_xmit_cleanup(vq, nb_used);
1028
1029         for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
1030                 struct rte_mbuf *txm = tx_pkts[nb_tx];
1031                 int can_push = 0, use_indirect = 0, slots, need;
1032
1033                 /* Do VLAN tag insertion */
1034                 if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
1035                         error = rte_vlan_insert(&txm);
1036                         if (unlikely(error)) {
1037                                 rte_pktmbuf_free(txm);
1038                                 continue;
1039                         }
1040                 }
1041
1042                 /* optimize ring usage */
1043                 if ((vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) ||
1044                       vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) &&
1045                     rte_mbuf_refcnt_read(txm) == 1 &&
1046                     RTE_MBUF_DIRECT(txm) &&
1047                     txm->nb_segs == 1 &&
1048                     rte_pktmbuf_headroom(txm) >= hdr_size &&
1049                     rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
1050                                    __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
1051                         can_push = 1;
1052                 else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
1053                          txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
1054                         use_indirect = 1;
1055
1056                 /* How many main ring entries are needed to this Tx?
1057                  * any_layout => number of segments
1058                  * indirect   => 1
1059                  * default    => number of segments + 1
1060                  */
1061                 slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
1062                 need = slots - vq->vq_free_cnt;
1063
1064                 /* Positive value indicates it need free vring descriptors */
1065                 if (unlikely(need > 0)) {
1066                         nb_used = VIRTQUEUE_NUSED(vq);
1067                         virtio_rmb();
1068                         need = RTE_MIN(need, (int)nb_used);
1069
1070                         virtio_xmit_cleanup(vq, need);
1071                         need = slots - vq->vq_free_cnt;
1072                         if (unlikely(need > 0)) {
1073                                 PMD_TX_LOG(ERR,
1074                                            "No free tx descriptors to transmit");
1075                                 break;
1076                         }
1077                 }
1078
1079                 /* Enqueue Packet buffers */
1080                 virtqueue_enqueue_xmit(txvq, txm, slots, use_indirect, can_push);
1081
1082                 txvq->stats.bytes += txm->pkt_len;
1083                 virtio_update_packet_stats(&txvq->stats, txm);
1084         }
1085
1086         txvq->stats.packets += nb_tx;
1087
1088         if (likely(nb_tx)) {
1089                 vq_update_avail_idx(vq);
1090
1091                 if (unlikely(virtqueue_kick_prepare(vq))) {
1092                         virtqueue_notify(vq);
1093                         PMD_TX_LOG(DEBUG, "Notified backend after xmit");
1094                 }
1095         }
1096
1097         return nb_tx;
1098 }