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
  54 #include "virtio_logs.h"
  55 #include "virtio_ethdev.h"
  56 #include "virtio_pci.h"
  57 #include "virtqueue.h"
  58 #include "virtio_rxtx.h"
  59
  60 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
  61 #define VIRTIO_DUMP_PACKET(m, len) rte_pktmbuf_dump(stdout, m, len)
  62 #else
  63 #define  VIRTIO_DUMP_PACKET(m, len) do { } while (0)
  64 #endif
  65
  66
  67 #define VIRTIO_SIMPLE_FLAGS ((uint32_t)ETH_TXQ_FLAGS_NOMULTSEGS | \
  68         ETH_TXQ_FLAGS_NOOFFLOADS)
  69
  70 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
  71 static int use_simple_rxtx;
  72 #endif
  73
  74 static void
  75 vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
  76 {
  77         struct vring_desc *dp, *dp_tail;
  78         struct vq_desc_extra *dxp;
  79         uint16_t desc_idx_last = desc_idx;
  80
  81         dp  = &vq->vq_ring.desc[desc_idx];
  82         dxp = &vq->vq_descx[desc_idx];
  83         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
  84         if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
  85                 while (dp->flags & VRING_DESC_F_NEXT) {
  86                         desc_idx_last = dp->next;
  87                         dp = &vq->vq_ring.desc[dp->next];
  88                 }
  89         }
  90         dxp->ndescs = 0;
  91
  92         /*
  93          * We must append the existing free chain, if any, to the end of
  94          * newly freed chain. If the virtqueue was completely used, then
  95          * head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
  96          */
  97         if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
  98                 vq->vq_desc_head_idx = desc_idx;
  99         } else {
 100                 dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
 101                 dp_tail->next = desc_idx;
 102         }
 103
 104         vq->vq_desc_tail_idx = desc_idx_last;
 105         dp->next = VQ_RING_DESC_CHAIN_END;
 106 }
 107
 108 static uint16_t
 109 virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts,
 110                            uint32_t *len, uint16_t num)
 111 {
 112         struct vring_used_elem *uep;
 113         struct rte_mbuf *cookie;
 114         uint16_t used_idx, desc_idx;
 115         uint16_t i;
 116
 117         /*  Caller does the check */
 118         for (i = 0; i < num ; i++) {
 119                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 120                 uep = &vq->vq_ring.used->ring[used_idx];
 121                 desc_idx = (uint16_t) uep->id;
 122                 len[i] = uep->len;
 123                 cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
 124
 125                 if (unlikely(cookie == NULL)) {
 126                         PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
 127                                 vq->vq_used_cons_idx);
 128                         break;
 129                 }
 130
 131                 rte_prefetch0(cookie);
 132                 rte_packet_prefetch(rte_pktmbuf_mtod(cookie, void *));
 133                 rx_pkts[i]  = cookie;
 134                 vq->vq_used_cons_idx++;
 135                 vq_ring_free_chain(vq, desc_idx);
 136                 vq->vq_descx[desc_idx].cookie = NULL;
 137         }
 138
 139         return i;
 140 }
 141
 142 #ifndef DEFAULT_TX_FREE_THRESH
 143 #define DEFAULT_TX_FREE_THRESH 32
 144 #endif
 145
 146 /* Cleanup from completed transmits. */
 147 static void
 148 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num)
 149 {
 150         uint16_t i, used_idx, desc_idx;
 151         for (i = 0; i < num; i++) {
 152                 struct vring_used_elem *uep;
 153                 struct vq_desc_extra *dxp;
 154
 155                 used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 156                 uep = &vq->vq_ring.used->ring[used_idx];
 157
 158                 desc_idx = (uint16_t) uep->id;
 159                 dxp = &vq->vq_descx[desc_idx];
 160                 vq->vq_used_cons_idx++;
 161                 vq_ring_free_chain(vq, desc_idx);
 162
 163                 if (dxp->cookie != NULL) {
 164                         rte_pktmbuf_free(dxp->cookie);
 165                         dxp->cookie = NULL;
 166                 }
 167         }
 168 }
 169
 170
 171 static inline int
 172 virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf *cookie)
 173 {
 174         struct vq_desc_extra *dxp;
 175         struct virtio_hw *hw = vq->hw;
 176         struct vring_desc *start_dp;
 177         uint16_t needed = 1;
 178         uint16_t head_idx, idx;
 179
 180         if (unlikely(vq->vq_free_cnt == 0))
 181                 return -ENOSPC;
 182         if (unlikely(vq->vq_free_cnt < needed))
 183                 return -EMSGSIZE;
 184
 185         head_idx = vq->vq_desc_head_idx;
 186         if (unlikely(head_idx >= vq->vq_nentries))
 187                 return -EFAULT;
 188
 189         idx = head_idx;
 190         dxp = &vq->vq_descx[idx];
 191         dxp->cookie = (void *)cookie;
 192         dxp->ndescs = needed;
 193
 194         start_dp = vq->vq_ring.desc;
 195         start_dp[idx].addr =
 196                 (uint64_t)(cookie->buf_physaddr + RTE_PKTMBUF_HEADROOM
 197                 - hw->vtnet_hdr_size);
 198         start_dp[idx].len =
 199                 cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 200         start_dp[idx].flags =  VRING_DESC_F_WRITE;
 201         idx = start_dp[idx].next;
 202         vq->vq_desc_head_idx = idx;
 203         if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 204                 vq->vq_desc_tail_idx = idx;
 205         vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
 206         vq_update_avail_ring(vq, head_idx);
 207
 208         return 0;
 209 }
 210
 211 static int
 212 virtqueue_enqueue_xmit(struct virtqueue *txvq, struct rte_mbuf *cookie,
 213                        uint16_t needed, int use_indirect, int can_push)
 214 {
 215         struct vq_desc_extra *dxp;
 216         struct vring_desc *start_dp;
 217         uint16_t seg_num = cookie->nb_segs;
 218         uint16_t head_idx, idx;
 219         uint16_t head_size = txvq->hw->vtnet_hdr_size;
 220         unsigned long offs;
 221
 222         if (unlikely(txvq->vq_free_cnt == 0))
 223                 return -ENOSPC;
 224         if (unlikely(txvq->vq_free_cnt < needed))
 225                 return -EMSGSIZE;
 226         head_idx = txvq->vq_desc_head_idx;
 227         if (unlikely(head_idx >= txvq->vq_nentries))
 228                 return -EFAULT;
 229
 230         idx = head_idx;
 231         dxp = &txvq->vq_descx[idx];
 232         dxp->cookie = (void *)cookie;
 233         dxp->ndescs = needed;
 234
 235         start_dp = txvq->vq_ring.desc;
 236
 237         if (can_push) {
 238                 /* put on zero'd transmit header (no offloads) */
 239                 void *hdr = rte_pktmbuf_prepend(cookie, head_size);
 240
 241                 memset(hdr, 0, head_size);
 242         } else if (use_indirect) {
 243                 /* setup tx ring slot to point to indirect
 244                  * descriptor list stored in reserved region.
 245                  *
 246                  * the first slot in indirect ring is already preset
 247                  * to point to the header in reserved region
 248                  */
 249                 struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr;
 250
 251                 offs = idx * sizeof(struct virtio_tx_region)
 252                         + offsetof(struct virtio_tx_region, tx_indir);
 253
 254                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem + offs;
 255                 start_dp[idx].len   = (seg_num + 1) * sizeof(struct vring_desc);
 256                 start_dp[idx].flags = VRING_DESC_F_INDIRECT;
 257
 258                 /* loop below will fill in rest of the indirect elements */
 259                 start_dp = txr[idx].tx_indir;
 260                 idx = 1;
 261         } else {
 262                 /* setup first tx ring slot to point to header
 263                  * stored in reserved region.
 264                  */
 265                 offs = idx * sizeof(struct virtio_tx_region)
 266                         + offsetof(struct virtio_tx_region, tx_hdr);
 267
 268                 start_dp[idx].addr  = txvq->virtio_net_hdr_mem + offs;
 269                 start_dp[idx].len   = txvq->hw->vtnet_hdr_size;
 270                 start_dp[idx].flags = VRING_DESC_F_NEXT;
 271                 idx = start_dp[idx].next;
 272         }
 273
 274         do {
 275                 start_dp[idx].addr  = rte_mbuf_data_dma_addr(cookie);
 276                 start_dp[idx].len   = cookie->data_len;
 277                 start_dp[idx].flags = cookie->next ? VRING_DESC_F_NEXT : 0;
 278                 idx = start_dp[idx].next;
 279         } while ((cookie = cookie->next) != NULL);
 280
 281         start_dp[idx].flags &= ~VRING_DESC_F_NEXT;
 282
 283         if (use_indirect)
 284                 idx = txvq->vq_ring.desc[head_idx].next;
 285
 286         txvq->vq_desc_head_idx = idx;
 287         if (txvq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
 288                 txvq->vq_desc_tail_idx = idx;
 289         txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
 290         vq_update_avail_ring(txvq, head_idx);
 291
 292         return 0;
 293 }
 294
 295 static inline struct rte_mbuf *
 296 rte_rxmbuf_alloc(struct rte_mempool *mp)
 297 {
 298         struct rte_mbuf *m;
 299
 300         m = __rte_mbuf_raw_alloc(mp);
 301         __rte_mbuf_sanity_check_raw(m, 0);
 302
 303         return m;
 304 }
 305
 306 static void
 307 virtio_dev_vring_start(struct virtqueue *vq, int queue_type)
 308 {
 309         struct rte_mbuf *m;
 310         int i, nbufs, error, size = vq->vq_nentries;
 311         struct vring *vr = &vq->vq_ring;
 312         uint8_t *ring_mem = vq->vq_ring_virt_mem;
 313
 314         PMD_INIT_FUNC_TRACE();
 315
 316         /*
 317          * Reinitialise since virtio port might have been stopped and restarted
 318          */
 319         memset(vq->vq_ring_virt_mem, 0, vq->vq_ring_size);
 320         vring_init(vr, size, ring_mem, VIRTIO_PCI_VRING_ALIGN);
 321         vq->vq_used_cons_idx = 0;
 322         vq->vq_desc_head_idx = 0;
 323         vq->vq_avail_idx = 0;
 324         vq->vq_desc_tail_idx = (uint16_t)(vq->vq_nentries - 1);
 325         vq->vq_free_cnt = vq->vq_nentries;
 326         memset(vq->vq_descx, 0, sizeof(struct vq_desc_extra) * vq->vq_nentries);
 327
 328         vring_desc_init(vr->desc, size);
 329
 330         /*
 331          * Disable device(host) interrupting guest
 332          */
 333         virtqueue_disable_intr(vq);
 334
 335         /* Only rx virtqueue needs mbufs to be allocated at initialization */
 336         if (queue_type == VTNET_RQ) {
 337                 if (vq->mpool == NULL)
 338                         rte_exit(EXIT_FAILURE,
 339                         "Cannot allocate initial mbufs for rx virtqueue");
 340
 341                 /* Allocate blank mbufs for the each rx descriptor */
 342                 nbufs = 0;
 343                 error = ENOSPC;
 344
 345 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 346                 if (use_simple_rxtx)
 347                         for (i = 0; i < vq->vq_nentries; i++) {
 348                                 vq->vq_ring.avail->ring[i] = i;
 349                                 vq->vq_ring.desc[i].flags = VRING_DESC_F_WRITE;
 350                         }
 351 #endif
 352                 memset(&vq->fake_mbuf, 0, sizeof(vq->fake_mbuf));
 353                 for (i = 0; i < RTE_PMD_VIRTIO_RX_MAX_BURST; i++)
 354                         vq->sw_ring[vq->vq_nentries + i] = &vq->fake_mbuf;
 355
 356                 while (!virtqueue_full(vq)) {
 357                         m = rte_rxmbuf_alloc(vq->mpool);
 358                         if (m == NULL)
 359                                 break;
 360
 361                         /******************************************
 362                         *         Enqueue allocated buffers        *
 363                         *******************************************/
 364 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 365                         if (use_simple_rxtx)
 366                                 error = virtqueue_enqueue_recv_refill_simple(vq, m);
 367                         else
 368 #endif
 369                                 error = virtqueue_enqueue_recv_refill(vq, m);
 370                         if (error) {
 371                                 rte_pktmbuf_free(m);
 372                                 break;
 373                         }
 374                         nbufs++;
 375                 }
 376
 377                 vq_update_avail_idx(vq);
 378
 379                 PMD_INIT_LOG(DEBUG, "Allocated %d bufs", nbufs);
 380         } else if (queue_type == VTNET_TQ) {
 381 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 382                 if (use_simple_rxtx) {
 383                         int mid_idx  = vq->vq_nentries >> 1;
 384                         for (i = 0; i < mid_idx; i++) {
 385                                 vq->vq_ring.avail->ring[i] = i + mid_idx;
 386                                 vq->vq_ring.desc[i + mid_idx].next = i;
 387                                 vq->vq_ring.desc[i + mid_idx].addr =
 388                                         vq->virtio_net_hdr_mem +
 389                                                 i * vq->hw->vtnet_hdr_size;
 390                                 vq->vq_ring.desc[i + mid_idx].len =
 391                                         vq->hw->vtnet_hdr_size;
 392                                 vq->vq_ring.desc[i + mid_idx].flags =
 393                                         VRING_DESC_F_NEXT;
 394                                 vq->vq_ring.desc[i].flags = 0;
 395                         }
 396                         for (i = mid_idx; i < vq->vq_nentries; i++)
 397                                 vq->vq_ring.avail->ring[i] = i;
 398                 }
 399 #endif
 400         }
 401 }
 402
 403 void
 404 virtio_dev_cq_start(struct rte_eth_dev *dev)
 405 {
 406         struct virtio_hw *hw = dev->data->dev_private;
 407
 408         if (hw->cvq) {
 409                 virtio_dev_vring_start(hw->cvq, VTNET_CQ);
 410                 VIRTQUEUE_DUMP((struct virtqueue *)hw->cvq);
 411         }
 412 }
 413
 414 void
 415 virtio_dev_rxtx_start(struct rte_eth_dev *dev)
 416 {
 417         /*
 418          * Start receive and transmit vrings
 419          * -    Setup vring structure for all queues
 420          * -    Initialize descriptor for the rx vring
 421          * -    Allocate blank mbufs for the each rx descriptor
 422          *
 423          */
 424         int i;
 425
 426         PMD_INIT_FUNC_TRACE();
 427
 428         /* Start rx vring. */
 429         for (i = 0; i < dev->data->nb_rx_queues; i++) {
 430                 virtio_dev_vring_start(dev->data->rx_queues[i], VTNET_RQ);
 431                 VIRTQUEUE_DUMP((struct virtqueue *)dev->data->rx_queues[i]);
 432         }
 433
 434         /* Start tx vring. */
 435         for (i = 0; i < dev->data->nb_tx_queues; i++) {
 436                 virtio_dev_vring_start(dev->data->tx_queues[i], VTNET_TQ);
 437                 VIRTQUEUE_DUMP((struct virtqueue *)dev->data->tx_queues[i]);
 438         }
 439 }
 440
 441 int
 442 virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
 443                         uint16_t queue_idx,
 444                         uint16_t nb_desc,
 445                         unsigned int socket_id,
 446                         __rte_unused const struct rte_eth_rxconf *rx_conf,
 447                         struct rte_mempool *mp)
 448 {
 449         uint16_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_RQ_QUEUE_IDX;
 450         struct virtqueue *vq;
 451         int ret;
 452
 453         PMD_INIT_FUNC_TRACE();
 454         ret = virtio_dev_queue_setup(dev, VTNET_RQ, queue_idx, vtpci_queue_idx,
 455                         nb_desc, socket_id, &vq);
 456         if (ret < 0) {
 457                 PMD_INIT_LOG(ERR, "rvq initialization failed");
 458                 return ret;
 459         }
 460
 461         /* Create mempool for rx mbuf allocation */
 462         vq->mpool = mp;
 463
 464         dev->data->rx_queues[queue_idx] = vq;
 465
 466 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 467         virtio_rxq_vec_setup(vq);
 468 #endif
 469
 470         return 0;
 471 }
 472
 473 void
 474 virtio_dev_rx_queue_release(void *rxq)
 475 {
 476         virtio_dev_queue_release(rxq);
 477 }
 478
 479 /*
 480  * struct rte_eth_dev *dev: Used to update dev
 481  * uint16_t nb_desc: Defaults to values read from config space
 482  * unsigned int socket_id: Used to allocate memzone
 483  * const struct rte_eth_txconf *tx_conf: Used to setup tx engine
 484  * uint16_t queue_idx: Just used as an index in dev txq list
 485  */
 486 int
 487 virtio_dev_tx_queue_setup(struct rte_eth_dev *dev,
 488                         uint16_t queue_idx,
 489                         uint16_t nb_desc,
 490                         unsigned int socket_id,
 491                         const struct rte_eth_txconf *tx_conf)
 492 {
 493         uint8_t vtpci_queue_idx = 2 * queue_idx + VTNET_SQ_TQ_QUEUE_IDX;
 494
 495 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 496         struct virtio_hw *hw = dev->data->dev_private;
 497 #endif
 498         struct virtqueue *vq;
 499         uint16_t tx_free_thresh;
 500         int ret;
 501
 502         PMD_INIT_FUNC_TRACE();
 503
 504         if ((tx_conf->txq_flags & ETH_TXQ_FLAGS_NOXSUMS)
 505             != ETH_TXQ_FLAGS_NOXSUMS) {
 506                 PMD_INIT_LOG(ERR, "TX checksum offload not supported\n");
 507                 return -EINVAL;
 508         }
 509
 510 #ifdef RTE_MACHINE_CPUFLAG_SSSE3
 511         /* Use simple rx/tx func if single segment and no offloads */
 512         if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
 513              !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
 514                 PMD_INIT_LOG(INFO, "Using simple rx/tx path");
 515                 dev->tx_pkt_burst = virtio_xmit_pkts_simple;
 516                 dev->rx_pkt_burst = virtio_recv_pkts_vec;
 517                 use_simple_rxtx = 1;
 518         }
 519 #endif
 520
 521         ret = virtio_dev_queue_setup(dev, VTNET_TQ, queue_idx, vtpci_queue_idx,
 522                         nb_desc, socket_id, &vq);
 523         if (ret < 0) {
 524                 PMD_INIT_LOG(ERR, "rvq initialization failed");
 525                 return ret;
 526         }
 527
 528         tx_free_thresh = tx_conf->tx_free_thresh;
 529         if (tx_free_thresh == 0)
 530                 tx_free_thresh =
 531                         RTE_MIN(vq->vq_nentries / 4, DEFAULT_TX_FREE_THRESH);
 532
 533         if (tx_free_thresh >= (vq->vq_nentries - 3)) {
 534                 RTE_LOG(ERR, PMD, "tx_free_thresh must be less than the "
 535                         "number of TX entries minus 3 (%u)."
 536                         " (tx_free_thresh=%u port=%u queue=%u)\n",
 537                         vq->vq_nentries - 3,
 538                         tx_free_thresh, dev->data->port_id, queue_idx);
 539                 return -EINVAL;
 540         }
 541
 542         vq->vq_free_thresh = tx_free_thresh;
 543
 544         dev->data->tx_queues[queue_idx] = vq;
 545         return 0;
 546 }
 547
 548 void
 549 virtio_dev_tx_queue_release(void *txq)
 550 {
 551         virtio_dev_queue_release(txq);
 552 }
 553
 554 static void
 555 virtio_discard_rxbuf(struct virtqueue *vq, struct rte_mbuf *m)
 556 {
 557         int error;
 558         /*
 559          * Requeue the discarded mbuf. This should always be
 560          * successful since it was just dequeued.
 561          */
 562         error = virtqueue_enqueue_recv_refill(vq, m);
 563         if (unlikely(error)) {
 564                 RTE_LOG(ERR, PMD, "cannot requeue discarded mbuf");
 565                 rte_pktmbuf_free(m);
 566         }
 567 }
 568
 569 static void
 570 virtio_update_packet_stats(struct virtqueue *vq, struct rte_mbuf *mbuf)
 571 {
 572         uint32_t s = mbuf->pkt_len;
 573         struct ether_addr *ea;
 574
 575         if (s == 64) {
 576                 vq->size_bins[1]++;
 577         } else if (s > 64 && s < 1024) {
 578                 uint32_t bin;
 579
 580                 /* count zeros, and offset into correct bin */
 581                 bin = (sizeof(s) * 8) - __builtin_clz(s) - 5;
 582                 vq->size_bins[bin]++;
 583         } else {
 584                 if (s < 64)
 585                         vq->size_bins[0]++;
 586                 else if (s < 1519)
 587                         vq->size_bins[6]++;
 588                 else if (s >= 1519)
 589                         vq->size_bins[7]++;
 590         }
 591
 592         ea = rte_pktmbuf_mtod(mbuf, struct ether_addr *);
 593         if (is_multicast_ether_addr(ea)) {
 594                 if (is_broadcast_ether_addr(ea))
 595                         vq->broadcast++;
 596                 else
 597                         vq->multicast++;
 598         }
 599 }
 600
 601 #define VIRTIO_MBUF_BURST_SZ 64
 602 #define DESC_PER_CACHELINE (RTE_CACHE_LINE_SIZE / sizeof(struct vring_desc))
 603 uint16_t
 604 virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 605 {
 606         struct virtqueue *rxvq = rx_queue;
 607         struct virtio_hw *hw;
 608         struct rte_mbuf *rxm, *new_mbuf;
 609         uint16_t nb_used, num, nb_rx;
 610         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 611         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 612         int error;
 613         uint32_t i, nb_enqueued;
 614         uint32_t hdr_size;
 615
 616         nb_used = VIRTQUEUE_NUSED(rxvq);
 617
 618         virtio_rmb();
 619
 620         num = (uint16_t)(likely(nb_used <= nb_pkts) ? nb_used : nb_pkts);
 621         num = (uint16_t)(likely(num <= VIRTIO_MBUF_BURST_SZ) ? num : VIRTIO_MBUF_BURST_SZ);
 622         if (likely(num > DESC_PER_CACHELINE))
 623                 num = num - ((rxvq->vq_used_cons_idx + num) % DESC_PER_CACHELINE);
 624
 625         if (num == 0)
 626                 return 0;
 627
 628         num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, num);
 629         PMD_RX_LOG(DEBUG, "used:%d dequeue:%d", nb_used, num);
 630
 631         hw = rxvq->hw;
 632         nb_rx = 0;
 633         nb_enqueued = 0;
 634         hdr_size = hw->vtnet_hdr_size;
 635
 636         for (i = 0; i < num ; i++) {
 637                 rxm = rcv_pkts[i];
 638
 639                 PMD_RX_LOG(DEBUG, "packet len:%d", len[i]);
 640
 641                 if (unlikely(len[i] < hdr_size + ETHER_HDR_LEN)) {
 642                         PMD_RX_LOG(ERR, "Packet drop");
 643                         nb_enqueued++;
 644                         virtio_discard_rxbuf(rxvq, rxm);
 645                         rxvq->errors++;
 646                         continue;
 647                 }
 648
 649                 rxm->port = rxvq->port_id;
 650                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 651                 rxm->ol_flags = 0;
 652                 rxm->vlan_tci = 0;
 653
 654                 rxm->nb_segs = 1;
 655                 rxm->next = NULL;
 656                 rxm->pkt_len = (uint32_t)(len[i] - hdr_size);
 657                 rxm->data_len = (uint16_t)(len[i] - hdr_size);
 658
 659                 if (hw->vlan_strip)
 660                         rte_vlan_strip(rxm);
 661
 662                 VIRTIO_DUMP_PACKET(rxm, rxm->data_len);
 663
 664                 rx_pkts[nb_rx++] = rxm;
 665
 666                 rxvq->bytes += rx_pkts[nb_rx - 1]->pkt_len;
 667                 virtio_update_packet_stats(rxvq, rxm);
 668         }
 669
 670         rxvq->packets += nb_rx;
 671
 672         /* Allocate new mbuf for the used descriptor */
 673         error = ENOSPC;
 674         while (likely(!virtqueue_full(rxvq))) {
 675                 new_mbuf = rte_rxmbuf_alloc(rxvq->mpool);
 676                 if (unlikely(new_mbuf == NULL)) {
 677                         struct rte_eth_dev *dev
 678                                 = &rte_eth_devices[rxvq->port_id];
 679                         dev->data->rx_mbuf_alloc_failed++;
 680                         break;
 681                 }
 682                 error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
 683                 if (unlikely(error)) {
 684                         rte_pktmbuf_free(new_mbuf);
 685                         break;
 686                 }
 687                 nb_enqueued++;
 688         }
 689
 690         if (likely(nb_enqueued)) {
 691                 vq_update_avail_idx(rxvq);
 692
 693                 if (unlikely(virtqueue_kick_prepare(rxvq))) {
 694                         virtqueue_notify(rxvq);
 695                         PMD_RX_LOG(DEBUG, "Notified\n");
 696                 }
 697         }
 698
 699         return nb_rx;
 700 }
 701
 702 uint16_t
 703 virtio_recv_mergeable_pkts(void *rx_queue,
 704                         struct rte_mbuf **rx_pkts,
 705                         uint16_t nb_pkts)
 706 {
 707         struct virtqueue *rxvq = rx_queue;
 708         struct virtio_hw *hw;
 709         struct rte_mbuf *rxm, *new_mbuf;
 710         uint16_t nb_used, num, nb_rx;
 711         uint32_t len[VIRTIO_MBUF_BURST_SZ];
 712         struct rte_mbuf *rcv_pkts[VIRTIO_MBUF_BURST_SZ];
 713         struct rte_mbuf *prev;
 714         int error;
 715         uint32_t i, nb_enqueued;
 716         uint32_t seg_num;
 717         uint16_t extra_idx;
 718         uint32_t seg_res;
 719         uint32_t hdr_size;
 720
 721         nb_used = VIRTQUEUE_NUSED(rxvq);
 722
 723         virtio_rmb();
 724
 725         if (nb_used == 0)
 726                 return 0;
 727
 728         PMD_RX_LOG(DEBUG, "used:%d\n", nb_used);
 729
 730         hw = rxvq->hw;
 731         nb_rx = 0;
 732         i = 0;
 733         nb_enqueued = 0;
 734         seg_num = 0;
 735         extra_idx = 0;
 736         seg_res = 0;
 737         hdr_size = hw->vtnet_hdr_size;
 738
 739         while (i < nb_used) {
 740                 struct virtio_net_hdr_mrg_rxbuf *header;
 741
 742                 if (nb_rx == nb_pkts)
 743                         break;
 744
 745                 num = virtqueue_dequeue_burst_rx(rxvq, rcv_pkts, len, 1);
 746                 if (num != 1)
 747                         continue;
 748
 749                 i++;
 750
 751                 PMD_RX_LOG(DEBUG, "dequeue:%d\n", num);
 752                 PMD_RX_LOG(DEBUG, "packet len:%d\n", len[0]);
 753
 754                 rxm = rcv_pkts[0];
 755
 756                 if (unlikely(len[0] < hdr_size + ETHER_HDR_LEN)) {
 757                         PMD_RX_LOG(ERR, "Packet drop\n");
 758                         nb_enqueued++;
 759                         virtio_discard_rxbuf(rxvq, rxm);
 760                         rxvq->errors++;
 761                         continue;
 762                 }
 763
 764                 header = (struct virtio_net_hdr_mrg_rxbuf *)((char *)rxm->buf_addr +
 765                         RTE_PKTMBUF_HEADROOM - hdr_size);
 766                 seg_num = header->num_buffers;
 767
 768                 if (seg_num == 0)
 769                         seg_num = 1;
 770
 771                 rxm->data_off = RTE_PKTMBUF_HEADROOM;
 772                 rxm->nb_segs = seg_num;
 773                 rxm->next = NULL;
 774                 rxm->ol_flags = 0;
 775                 rxm->vlan_tci = 0;
 776                 rxm->pkt_len = (uint32_t)(len[0] - hdr_size);
 777                 rxm->data_len = (uint16_t)(len[0] - hdr_size);
 778
 779                 rxm->port = rxvq->port_id;
 780                 rx_pkts[nb_rx] = rxm;
 781                 prev = rxm;
 782
 783                 seg_res = seg_num - 1;
 784
 785                 while (seg_res != 0) {
 786                         /*
 787                          * Get extra segments for current uncompleted packet.
 788                          */
 789                         uint16_t  rcv_cnt =
 790                                 RTE_MIN(seg_res, RTE_DIM(rcv_pkts));
 791                         if (likely(VIRTQUEUE_NUSED(rxvq) >= rcv_cnt)) {
 792                                 uint32_t rx_num =
 793                                         virtqueue_dequeue_burst_rx(rxvq,
 794                                         rcv_pkts, len, rcv_cnt);
 795                                 i += rx_num;
 796                                 rcv_cnt = rx_num;
 797                         } else {
 798                                 PMD_RX_LOG(ERR,
 799                                         "No enough segments for packet.\n");
 800                                 nb_enqueued++;
 801                                 virtio_discard_rxbuf(rxvq, rxm);
 802                                 rxvq->errors++;
 803                                 break;
 804                         }
 805
 806                         extra_idx = 0;
 807
 808                         while (extra_idx < rcv_cnt) {
 809                                 rxm = rcv_pkts[extra_idx];
 810
 811                                 rxm->data_off = RTE_PKTMBUF_HEADROOM - hdr_size;
 812                                 rxm->next = NULL;
 813                                 rxm->pkt_len = (uint32_t)(len[extra_idx]);
 814                                 rxm->data_len = (uint16_t)(len[extra_idx]);
 815
 816                                 if (prev)
 817                                         prev->next = rxm;
 818
 819                                 prev = rxm;
 820                                 rx_pkts[nb_rx]->pkt_len += rxm->pkt_len;
 821                                 extra_idx++;
 822                         };
 823                         seg_res -= rcv_cnt;
 824                 }
 825
 826                 if (hw->vlan_strip)
 827                         rte_vlan_strip(rx_pkts[nb_rx]);
 828
 829                 VIRTIO_DUMP_PACKET(rx_pkts[nb_rx],
 830                         rx_pkts[nb_rx]->data_len);
 831
 832                 rxvq->bytes += rx_pkts[nb_rx]->pkt_len;
 833                 virtio_update_packet_stats(rxvq, rx_pkts[nb_rx]);
 834                 nb_rx++;
 835         }
 836
 837         rxvq->packets += nb_rx;
 838
 839         /* Allocate new mbuf for the used descriptor */
 840         error = ENOSPC;
 841         while (likely(!virtqueue_full(rxvq))) {
 842                 new_mbuf = rte_rxmbuf_alloc(rxvq->mpool);
 843                 if (unlikely(new_mbuf == NULL)) {
 844                         struct rte_eth_dev *dev
 845                                 = &rte_eth_devices[rxvq->port_id];
 846                         dev->data->rx_mbuf_alloc_failed++;
 847                         break;
 848                 }
 849                 error = virtqueue_enqueue_recv_refill(rxvq, new_mbuf);
 850                 if (unlikely(error)) {
 851                         rte_pktmbuf_free(new_mbuf);
 852                         break;
 853                 }
 854                 nb_enqueued++;
 855         }
 856
 857         if (likely(nb_enqueued)) {
 858                 vq_update_avail_idx(rxvq);
 859
 860                 if (unlikely(virtqueue_kick_prepare(rxvq))) {
 861                         virtqueue_notify(rxvq);
 862                         PMD_RX_LOG(DEBUG, "Notified");
 863                 }
 864         }
 865
 866         return nb_rx;
 867 }
 868
 869 uint16_t
 870 virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 871 {
 872         struct virtqueue *txvq = tx_queue;
 873         struct virtio_hw *hw = txvq->hw;
 874         uint16_t hdr_size = hw->vtnet_hdr_size;
 875         uint16_t nb_used, nb_tx;
 876         int error;
 877
 878         if (unlikely(nb_pkts < 1))
 879                 return nb_pkts;
 880
 881         PMD_TX_LOG(DEBUG, "%d packets to xmit", nb_pkts);
 882         nb_used = VIRTQUEUE_NUSED(txvq);
 883
 884         virtio_rmb();
 885         if (likely(nb_used > txvq->vq_nentries - txvq->vq_free_thresh))
 886                 virtio_xmit_cleanup(txvq, nb_used);
 887
 888         for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
 889                 struct rte_mbuf *txm = tx_pkts[nb_tx];
 890                 int can_push = 0, use_indirect = 0, slots, need;
 891
 892                 /* Do VLAN tag insertion */
 893                 if (unlikely(txm->ol_flags & PKT_TX_VLAN_PKT)) {
 894                         error = rte_vlan_insert(&txm);
 895                         if (unlikely(error)) {
 896                                 rte_pktmbuf_free(txm);
 897                                 continue;
 898                         }
 899                 }
 900
 901                 /* optimize ring usage */
 902                 if (vtpci_with_feature(hw, VIRTIO_F_ANY_LAYOUT) &&
 903                     rte_mbuf_refcnt_read(txm) == 1 &&
 904                     txm->nb_segs == 1 &&
 905                     rte_pktmbuf_headroom(txm) >= hdr_size &&
 906                     rte_is_aligned(rte_pktmbuf_mtod(txm, char *),
 907                                    __alignof__(struct virtio_net_hdr_mrg_rxbuf)))
 908                         can_push = 1;
 909                 else if (vtpci_with_feature(hw, VIRTIO_RING_F_INDIRECT_DESC) &&
 910                          txm->nb_segs < VIRTIO_MAX_TX_INDIRECT)
 911                         use_indirect = 1;
 912
 913                 /* How many main ring entries are needed to this Tx?
 914                  * any_layout => number of segments
 915                  * indirect   => 1
 916                  * default    => number of segments + 1
 917                  */
 918                 slots = use_indirect ? 1 : (txm->nb_segs + !can_push);
 919                 need = slots - txvq->vq_free_cnt;
 920
 921                 /* Positive value indicates it need free vring descriptors */
 922                 if (unlikely(need > 0)) {
 923                         nb_used = VIRTQUEUE_NUSED(txvq);
 924                         virtio_rmb();
 925                         need = RTE_MIN(need, (int)nb_used);
 926
 927                         virtio_xmit_cleanup(txvq, need);
 928                         need = slots - txvq->vq_free_cnt;
 929                         if (unlikely(need > 0)) {
 930                                 PMD_TX_LOG(ERR,
 931                                            "No free tx descriptors to transmit");
 932                                 break;
 933                         }
 934                 }
 935
 936                 /* Enqueue Packet buffers */
 937                 error = virtqueue_enqueue_xmit(txvq, txm, slots,
 938                                                use_indirect, can_push);
 939                 if (unlikely(error)) {
 940                         if (error == ENOSPC)
 941                                 PMD_TX_LOG(ERR, "virtqueue_enqueue Free count = 0");
 942                         else if (error == EMSGSIZE)
 943                                 PMD_TX_LOG(ERR, "virtqueue_enqueue Free count < 1");
 944                         else
 945                                 PMD_TX_LOG(ERR, "virtqueue_enqueue error: %d", error);
 946                         break;
 947                 }
 948
 949                 txvq->bytes += txm->pkt_len;
 950                 virtio_update_packet_stats(txvq, txm);
 951         }
 952
 953         txvq->packets += nb_tx;
 954
 955         if (likely(nb_tx)) {
 956                 vq_update_avail_idx(txvq);
 957
 958                 if (unlikely(virtqueue_kick_prepare(txvq))) {
 959                         virtqueue_notify(txvq);
 960                         PMD_TX_LOG(DEBUG, "Notified backend after xmit");
 961                 }
 962         }
 963
 964         return nb_tx;
 965 }