drivers/net/enic/enic_rxtx.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2008-2017 Cisco Systems, Inc.  All rights reserved.
   3  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
   4  */
   5
   6 #include <rte_mbuf.h>
   7 #include <rte_ethdev_driver.h>
   8 #include <rte_net.h>
   9 #include <rte_prefetch.h>
  10
  11 #include "enic_compat.h"
  12 #include "rq_enet_desc.h"
  13 #include "enic.h"
  14 #include "enic_rxtx_common.h"
  15 #include <rte_ether.h>
  16 #include <rte_ip.h>
  17 #include <rte_tcp.h>
  18
  19 #define RTE_PMD_USE_PREFETCH
  20
  21 #ifdef RTE_PMD_USE_PREFETCH
  22 /*Prefetch a cache line into all cache levels. */
  23 #define rte_enic_prefetch(p) rte_prefetch0(p)
  24 #else
  25 #define rte_enic_prefetch(p) do {} while (0)
  26 #endif
  27
  28 #ifdef RTE_PMD_PACKET_PREFETCH
  29 #define rte_packet_prefetch(p) rte_prefetch1(p)
  30 #else
  31 #define rte_packet_prefetch(p) do {} while (0)
  32 #endif
  33
  34 /* dummy receive function to replace actual function in
  35  * order to do safe reconfiguration operations.
  36  */
  37 uint16_t
  38 enic_dummy_recv_pkts(__rte_unused void *rx_queue,
  39                      __rte_unused struct rte_mbuf **rx_pkts,
  40                      __rte_unused uint16_t nb_pkts)
  41 {
  42         return 0;
  43 }
  44
  45 uint16_t
  46 enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
  47                uint16_t nb_pkts)
  48 {
  49         struct vnic_rq *sop_rq = rx_queue;
  50         struct vnic_rq *data_rq;
  51         struct vnic_rq *rq;
  52         struct enic *enic = vnic_dev_priv(sop_rq->vdev);
  53         uint16_t cq_idx;
  54         uint16_t rq_idx, max_rx;
  55         uint16_t rq_num;
  56         struct rte_mbuf *nmb, *rxmb;
  57         uint16_t nb_rx = 0;
  58         struct vnic_cq *cq;
  59         volatile struct cq_desc *cqd_ptr;
  60         uint8_t color;
  61         uint8_t tnl;
  62         uint16_t seg_length;
  63         struct rte_mbuf *first_seg = sop_rq->pkt_first_seg;
  64         struct rte_mbuf *last_seg = sop_rq->pkt_last_seg;
  65
  66         cq = &enic->cq[enic_cq_rq(enic, sop_rq->index)];
  67         cq_idx = cq->to_clean;          /* index of cqd, rqd, mbuf_table */
  68         cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
  69         color = cq->last_color;
  70
  71         data_rq = &enic->rq[sop_rq->data_queue_idx];
  72
  73         /* Receive until the end of the ring, at most. */
  74         max_rx = RTE_MIN(nb_pkts, cq->ring.desc_count - cq_idx);
  75
  76         while (max_rx) {
  77                 volatile struct rq_enet_desc *rqd_ptr;
  78                 struct cq_desc cqd;
  79                 uint8_t packet_error;
  80                 uint16_t ciflags;
  81
  82                 max_rx--;
  83
  84                 /* Check for pkts available */
  85                 if ((cqd_ptr->type_color & CQ_DESC_COLOR_MASK_NOSHIFT) == color)
  86                         break;
  87
  88                 /* Get the cq descriptor and extract rq info from it */
  89                 cqd = *cqd_ptr;
  90                 rq_num = cqd.q_number & CQ_DESC_Q_NUM_MASK;
  91                 rq_idx = cqd.completed_index & CQ_DESC_COMP_NDX_MASK;
  92
  93                 rq = &enic->rq[rq_num];
  94                 rqd_ptr = ((struct rq_enet_desc *)rq->ring.descs) + rq_idx;
  95
  96                 /* allocate a new mbuf */
  97                 nmb = rte_mbuf_raw_alloc(rq->mp);
  98                 if (nmb == NULL) {
  99                         rte_atomic64_inc(&enic->soft_stats.rx_nombuf);
 100                         break;
 101                 }
 102
 103                 /* A packet error means descriptor and data are untrusted */
 104                 packet_error = enic_cq_rx_check_err(&cqd);
 105
 106                 /* Get the mbuf to return and replace with one just allocated */
 107                 rxmb = rq->mbuf_ring[rq_idx];
 108                 rq->mbuf_ring[rq_idx] = nmb;
 109                 cq_idx++;
 110
 111                 /* Prefetch next mbuf & desc while processing current one */
 112                 cqd_ptr = (struct cq_desc *)(cq->ring.descs) + cq_idx;
 113                 rte_enic_prefetch(cqd_ptr);
 114
 115                 ciflags = enic_cq_rx_desc_ciflags(
 116                         (struct cq_enet_rq_desc *)&cqd);
 117
 118                 /* Push descriptor for newly allocated mbuf */
 119                 nmb->data_off = RTE_PKTMBUF_HEADROOM;
 120                 /*
 121                  * Only the address needs to be refilled. length_type of the
 122                  * descriptor it set during initialization
 123                  * (enic_alloc_rx_queue_mbufs) and does not change.
 124                  */
 125                 rqd_ptr->address = rte_cpu_to_le_64(nmb->buf_iova +
 126                                                     RTE_PKTMBUF_HEADROOM);
 127
 128                 /* Fill in the rest of the mbuf */
 129                 seg_length = enic_cq_rx_desc_n_bytes(&cqd);
 130
 131                 if (rq->is_sop) {
 132                         first_seg = rxmb;
 133                         first_seg->pkt_len = seg_length;
 134                 } else {
 135                         first_seg->pkt_len = (uint16_t)(first_seg->pkt_len
 136                                                         + seg_length);
 137                         first_seg->nb_segs++;
 138                         last_seg->next = rxmb;
 139                 }
 140
 141                 rxmb->port = enic->port_id;
 142                 rxmb->data_len = seg_length;
 143
 144                 rq->rx_nb_hold++;
 145
 146                 if (!(enic_cq_rx_desc_eop(ciflags))) {
 147                         last_seg = rxmb;
 148                         continue;
 149                 }
 150
 151                 /*
 152                  * When overlay offload is enabled, CQ.fcoe indicates the
 153                  * packet is tunnelled.
 154                  */
 155                 tnl = enic->overlay_offload &&
 156                         (ciflags & CQ_ENET_RQ_DESC_FLAGS_FCOE) != 0;
 157                 /* cq rx flags are only valid if eop bit is set */
 158                 first_seg->packet_type =
 159                         enic_cq_rx_flags_to_pkt_type(&cqd, tnl);
 160                 enic_cq_rx_to_pkt_flags(&cqd, first_seg);
 161
 162                 /* Wipe the outer types set by enic_cq_rx_flags_to_pkt_type() */
 163                 if (tnl) {
 164                         first_seg->packet_type &= ~(RTE_PTYPE_L3_MASK |
 165                                                     RTE_PTYPE_L4_MASK);
 166                 }
 167                 if (unlikely(packet_error)) {
 168                         rte_pktmbuf_free(first_seg);
 169                         rte_atomic64_inc(&enic->soft_stats.rx_packet_errors);
 170                         continue;
 171                 }
 172
 173
 174                 /* prefetch mbuf data for caller */
 175                 rte_packet_prefetch(RTE_PTR_ADD(first_seg->buf_addr,
 176                                     RTE_PKTMBUF_HEADROOM));
 177
 178                 /* store the mbuf address into the next entry of the array */
 179                 rx_pkts[nb_rx++] = first_seg;
 180         }
 181         if (unlikely(cq_idx == cq->ring.desc_count)) {
 182                 cq_idx = 0;
 183                 cq->last_color ^= CQ_DESC_COLOR_MASK_NOSHIFT;
 184         }
 185
 186         sop_rq->pkt_first_seg = first_seg;
 187         sop_rq->pkt_last_seg = last_seg;
 188
 189         cq->to_clean = cq_idx;
 190
 191         if ((sop_rq->rx_nb_hold + data_rq->rx_nb_hold) >
 192             sop_rq->rx_free_thresh) {
 193                 if (data_rq->in_use) {
 194                         data_rq->posted_index =
 195                                 enic_ring_add(data_rq->ring.desc_count,
 196                                               data_rq->posted_index,
 197                                               data_rq->rx_nb_hold);
 198                         data_rq->rx_nb_hold = 0;
 199                 }
 200                 sop_rq->posted_index = enic_ring_add(sop_rq->ring.desc_count,
 201                                                      sop_rq->posted_index,
 202                                                      sop_rq->rx_nb_hold);
 203                 sop_rq->rx_nb_hold = 0;
 204
 205                 rte_mb();
 206                 if (data_rq->in_use)
 207                         iowrite32_relaxed(data_rq->posted_index,
 208                                           &data_rq->ctrl->posted_index);
 209                 rte_compiler_barrier();
 210                 iowrite32_relaxed(sop_rq->posted_index,
 211                                   &sop_rq->ctrl->posted_index);
 212         }
 213
 214
 215         return nb_rx;
 216 }
 217
 218 uint16_t
 219 enic_noscatter_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 220                          uint16_t nb_pkts)
 221 {
 222         struct rte_mbuf *mb, **rx, **rxmb;
 223         uint16_t cq_idx, nb_rx, max_rx;
 224         struct cq_enet_rq_desc *cqd;
 225         struct rq_enet_desc *rqd;
 226         unsigned int port_id;
 227         struct vnic_cq *cq;
 228         struct vnic_rq *rq;
 229         struct enic *enic;
 230         uint8_t color;
 231         bool overlay;
 232         bool tnl;
 233
 234         rq = rx_queue;
 235         enic = vnic_dev_priv(rq->vdev);
 236         cq = &enic->cq[enic_cq_rq(enic, rq->index)];
 237         cq_idx = cq->to_clean;
 238
 239         /*
 240          * Fill up the reserve of free mbufs. Below, we restock the receive
 241          * ring with these mbufs to avoid allocation failures.
 242          */
 243         if (rq->num_free_mbufs == 0) {
 244                 if (rte_mempool_get_bulk(rq->mp, (void **)rq->free_mbufs,
 245                                          ENIC_RX_BURST_MAX))
 246                         return 0;
 247                 rq->num_free_mbufs = ENIC_RX_BURST_MAX;
 248         }
 249
 250         /* Receive until the end of the ring, at most. */
 251         max_rx = RTE_MIN(nb_pkts, rq->num_free_mbufs);
 252         max_rx = RTE_MIN(max_rx, cq->ring.desc_count - cq_idx);
 253
 254         cqd = (struct cq_enet_rq_desc *)(cq->ring.descs) + cq_idx;
 255         color = cq->last_color;
 256         rxmb = rq->mbuf_ring + cq_idx;
 257         port_id = enic->port_id;
 258         overlay = enic->overlay_offload;
 259
 260         rx = rx_pkts;
 261         while (max_rx) {
 262                 max_rx--;
 263                 if ((cqd->type_color & CQ_DESC_COLOR_MASK_NOSHIFT) == color)
 264                         break;
 265                 if (unlikely(cqd->bytes_written_flags &
 266                              CQ_ENET_RQ_DESC_FLAGS_TRUNCATED)) {
 267                         rte_pktmbuf_free(*rxmb++);
 268                         rte_atomic64_inc(&enic->soft_stats.rx_packet_errors);
 269                         cqd++;
 270                         continue;
 271                 }
 272
 273                 mb = *rxmb++;
 274                 /* prefetch mbuf data for caller */
 275                 rte_packet_prefetch(RTE_PTR_ADD(mb->buf_addr,
 276                                     RTE_PKTMBUF_HEADROOM));
 277                 mb->data_len = cqd->bytes_written_flags &
 278                         CQ_ENET_RQ_DESC_BYTES_WRITTEN_MASK;
 279                 mb->pkt_len = mb->data_len;
 280                 mb->port = port_id;
 281                 tnl = overlay && (cqd->completed_index_flags &
 282                                   CQ_ENET_RQ_DESC_FLAGS_FCOE) != 0;
 283                 mb->packet_type =
 284                         enic_cq_rx_flags_to_pkt_type((struct cq_desc *)cqd,
 285                                                      tnl);
 286                 enic_cq_rx_to_pkt_flags((struct cq_desc *)cqd, mb);
 287                 /* Wipe the outer types set by enic_cq_rx_flags_to_pkt_type() */
 288                 if (tnl) {
 289                         mb->packet_type &= ~(RTE_PTYPE_L3_MASK |
 290                                              RTE_PTYPE_L4_MASK);
 291                 }
 292                 cqd++;
 293                 *rx++ = mb;
 294         }
 295         /* Number of descriptors visited */
 296         nb_rx = cqd - (struct cq_enet_rq_desc *)(cq->ring.descs) - cq_idx;
 297         if (nb_rx == 0)
 298                 return 0;
 299         rqd = ((struct rq_enet_desc *)rq->ring.descs) + cq_idx;
 300         rxmb = rq->mbuf_ring + cq_idx;
 301         cq_idx += nb_rx;
 302         rq->rx_nb_hold += nb_rx;
 303         if (unlikely(cq_idx == cq->ring.desc_count)) {
 304                 cq_idx = 0;
 305                 cq->last_color ^= CQ_DESC_COLOR_MASK_NOSHIFT;
 306         }
 307         cq->to_clean = cq_idx;
 308
 309         memcpy(rxmb, rq->free_mbufs + ENIC_RX_BURST_MAX - rq->num_free_mbufs,
 310                sizeof(struct rte_mbuf *) * nb_rx);
 311         rq->num_free_mbufs -= nb_rx;
 312         while (nb_rx) {
 313                 nb_rx--;
 314                 mb = *rxmb++;
 315                 mb->data_off = RTE_PKTMBUF_HEADROOM;
 316                 rqd->address = mb->buf_iova + RTE_PKTMBUF_HEADROOM;
 317                 rqd++;
 318         }
 319         if (rq->rx_nb_hold > rq->rx_free_thresh) {
 320                 rq->posted_index = enic_ring_add(rq->ring.desc_count,
 321                                                  rq->posted_index,
 322                                                  rq->rx_nb_hold);
 323                 rq->rx_nb_hold = 0;
 324                 rte_wmb();
 325                 iowrite32_relaxed(rq->posted_index,
 326                                   &rq->ctrl->posted_index);
 327         }
 328
 329         return rx - rx_pkts;
 330 }
 331
 332 static inline void enic_free_wq_bufs(struct vnic_wq *wq,
 333                                      uint16_t completed_index)
 334 {
 335         struct rte_mbuf *buf;
 336         struct rte_mbuf *m, *free[ENIC_MAX_WQ_DESCS];
 337         unsigned int nb_to_free, nb_free = 0, i;
 338         struct rte_mempool *pool;
 339         unsigned int tail_idx;
 340         unsigned int desc_count = wq->ring.desc_count;
 341
 342         nb_to_free = enic_ring_sub(desc_count, wq->tail_idx, completed_index)
 343                                    + 1;
 344         tail_idx = wq->tail_idx;
 345         pool = wq->bufs[tail_idx]->pool;
 346         for (i = 0; i < nb_to_free; i++) {
 347                 buf = wq->bufs[tail_idx];
 348                 m = rte_pktmbuf_prefree_seg(buf);
 349                 if (unlikely(m == NULL)) {
 350                         tail_idx = enic_ring_incr(desc_count, tail_idx);
 351                         continue;
 352                 }
 353
 354                 if (likely(m->pool == pool)) {
 355                         RTE_ASSERT(nb_free < ENIC_MAX_WQ_DESCS);
 356                         free[nb_free++] = m;
 357                 } else {
 358                         rte_mempool_put_bulk(pool, (void *)free, nb_free);
 359                         free[0] = m;
 360                         nb_free = 1;
 361                         pool = m->pool;
 362                 }
 363                 tail_idx = enic_ring_incr(desc_count, tail_idx);
 364         }
 365
 366         if (nb_free > 0)
 367                 rte_mempool_put_bulk(pool, (void **)free, nb_free);
 368
 369         wq->tail_idx = tail_idx;
 370         wq->ring.desc_avail += nb_to_free;
 371 }
 372
 373 unsigned int enic_cleanup_wq(__rte_unused struct enic *enic, struct vnic_wq *wq)
 374 {
 375         uint16_t completed_index;
 376
 377         completed_index = *((uint32_t *)wq->cqmsg_rz->addr) & 0xffff;
 378
 379         if (wq->last_completed_index != completed_index) {
 380                 enic_free_wq_bufs(wq, completed_index);
 381                 wq->last_completed_index = completed_index;
 382         }
 383         return 0;
 384 }
 385
 386 uint16_t enic_prep_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 387                         uint16_t nb_pkts)
 388 {
 389         struct vnic_wq *wq = (struct vnic_wq *)tx_queue;
 390         int32_t ret;
 391         uint16_t i;
 392         uint64_t ol_flags;
 393         struct rte_mbuf *m;
 394
 395         for (i = 0; i != nb_pkts; i++) {
 396                 m = tx_pkts[i];
 397                 ol_flags = m->ol_flags;
 398                 if (!(ol_flags & PKT_TX_TCP_SEG)) {
 399                         if (unlikely(m->pkt_len > ENIC_TX_MAX_PKT_SIZE)) {
 400                                 rte_errno = EINVAL;
 401                                 return i;
 402                         }
 403                 } else {
 404                         uint16_t header_len;
 405
 406                         header_len = m->l2_len + m->l3_len + m->l4_len;
 407                         if (m->tso_segsz + header_len > ENIC_TX_MAX_PKT_SIZE) {
 408                                 rte_errno = EINVAL;
 409                                 return i;
 410                         }
 411                 }
 412
 413                 if (ol_flags & wq->tx_offload_notsup_mask) {
 414                         rte_errno = ENOTSUP;
 415                         return i;
 416                 }
 417 #ifdef RTE_LIBRTE_ETHDEV_DEBUG
 418                 ret = rte_validate_tx_offload(m);
 419                 if (ret != 0) {
 420                         rte_errno = -ret;
 421                         return i;
 422                 }
 423 #endif
 424                 ret = rte_net_intel_cksum_prepare(m);
 425                 if (ret != 0) {
 426                         rte_errno = -ret;
 427                         return i;
 428                 }
 429         }
 430
 431         return i;
 432 }
 433
 434 uint16_t enic_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 435         uint16_t nb_pkts)
 436 {
 437         uint16_t index;
 438         unsigned int pkt_len, data_len;
 439         unsigned int nb_segs;
 440         struct rte_mbuf *tx_pkt;
 441         struct vnic_wq *wq = (struct vnic_wq *)tx_queue;
 442         struct enic *enic = vnic_dev_priv(wq->vdev);
 443         unsigned short vlan_id;
 444         uint64_t ol_flags;
 445         uint64_t ol_flags_mask;
 446         unsigned int wq_desc_avail;
 447         int head_idx;
 448         unsigned int desc_count;
 449         struct wq_enet_desc *descs, *desc_p, desc_tmp;
 450         uint16_t mss;
 451         uint8_t vlan_tag_insert;
 452         uint8_t eop, cq;
 453         uint64_t bus_addr;
 454         uint8_t offload_mode;
 455         uint16_t header_len;
 456         uint64_t tso;
 457         rte_atomic64_t *tx_oversized;
 458
 459         enic_cleanup_wq(enic, wq);
 460         wq_desc_avail = vnic_wq_desc_avail(wq);
 461         head_idx = wq->head_idx;
 462         desc_count = wq->ring.desc_count;
 463         ol_flags_mask = PKT_TX_VLAN | PKT_TX_IP_CKSUM | PKT_TX_L4_MASK;
 464         tx_oversized = &enic->soft_stats.tx_oversized;
 465
 466         nb_pkts = RTE_MIN(nb_pkts, ENIC_TX_XMIT_MAX);
 467
 468         for (index = 0; index < nb_pkts; index++) {
 469                 tx_pkt = *tx_pkts++;
 470                 pkt_len = tx_pkt->pkt_len;
 471                 data_len = tx_pkt->data_len;
 472                 ol_flags = tx_pkt->ol_flags;
 473                 nb_segs = tx_pkt->nb_segs;
 474                 tso = ol_flags & PKT_TX_TCP_SEG;
 475
 476                 /* drop packet if it's too big to send */
 477                 if (unlikely(!tso && pkt_len > ENIC_TX_MAX_PKT_SIZE)) {
 478                         rte_pktmbuf_free(tx_pkt);
 479                         rte_atomic64_inc(tx_oversized);
 480                         continue;
 481                 }
 482
 483                 if (nb_segs > wq_desc_avail) {
 484                         if (index > 0)
 485                                 goto post;
 486                         goto done;
 487                 }
 488
 489                 mss = 0;
 490                 vlan_id = tx_pkt->vlan_tci;
 491                 vlan_tag_insert = !!(ol_flags & PKT_TX_VLAN);
 492                 bus_addr = (dma_addr_t)
 493                            (tx_pkt->buf_iova + tx_pkt->data_off);
 494
 495                 descs = (struct wq_enet_desc *)wq->ring.descs;
 496                 desc_p = descs + head_idx;
 497
 498                 eop = (data_len == pkt_len);
 499                 offload_mode = WQ_ENET_OFFLOAD_MODE_CSUM;
 500                 header_len = 0;
 501
 502                 if (tso) {
 503                         header_len = tx_pkt->l2_len + tx_pkt->l3_len +
 504                                      tx_pkt->l4_len;
 505
 506                         /* Drop if non-TCP packet or TSO seg size is too big */
 507                         if (unlikely(header_len == 0 || ((tx_pkt->tso_segsz +
 508                             header_len) > ENIC_TX_MAX_PKT_SIZE))) {
 509                                 rte_pktmbuf_free(tx_pkt);
 510                                 rte_atomic64_inc(tx_oversized);
 511                                 continue;
 512                         }
 513
 514                         offload_mode = WQ_ENET_OFFLOAD_MODE_TSO;
 515                         mss = tx_pkt->tso_segsz;
 516                         /* For tunnel, need the size of outer+inner headers */
 517                         if (ol_flags & PKT_TX_TUNNEL_MASK) {
 518                                 header_len += tx_pkt->outer_l2_len +
 519                                         tx_pkt->outer_l3_len;
 520                         }
 521                 }
 522
 523                 if ((ol_flags & ol_flags_mask) && (header_len == 0)) {
 524                         if (ol_flags & PKT_TX_IP_CKSUM)
 525                                 mss |= ENIC_CALC_IP_CKSUM;
 526
 527                         /* Nic uses just 1 bit for UDP and TCP */
 528                         switch (ol_flags & PKT_TX_L4_MASK) {
 529                         case PKT_TX_TCP_CKSUM:
 530                         case PKT_TX_UDP_CKSUM:
 531                                 mss |= ENIC_CALC_TCP_UDP_CKSUM;
 532                                 break;
 533                         }
 534                 }
 535                 wq->cq_pend++;
 536                 cq = 0;
 537                 if (eop && wq->cq_pend >= ENIC_WQ_CQ_THRESH) {
 538                         cq = 1;
 539                         wq->cq_pend = 0;
 540                 }
 541                 wq_enet_desc_enc(&desc_tmp, bus_addr, data_len, mss, header_len,
 542                                  offload_mode, eop, cq, 0, vlan_tag_insert,
 543                                  vlan_id, 0);
 544
 545                 *desc_p = desc_tmp;
 546                 wq->bufs[head_idx] = tx_pkt;
 547                 head_idx = enic_ring_incr(desc_count, head_idx);
 548                 wq_desc_avail--;
 549
 550                 if (!eop) {
 551                         for (tx_pkt = tx_pkt->next; tx_pkt; tx_pkt =
 552                             tx_pkt->next) {
 553                                 data_len = tx_pkt->data_len;
 554
 555                                 wq->cq_pend++;
 556                                 cq = 0;
 557                                 if (tx_pkt->next == NULL) {
 558                                         eop = 1;
 559                                         if (wq->cq_pend >= ENIC_WQ_CQ_THRESH) {
 560                                                 cq = 1;
 561                                                 wq->cq_pend = 0;
 562                                         }
 563                                 }
 564                                 desc_p = descs + head_idx;
 565                                 bus_addr = (dma_addr_t)(tx_pkt->buf_iova
 566                                            + tx_pkt->data_off);
 567                                 wq_enet_desc_enc((struct wq_enet_desc *)
 568                                                  &desc_tmp, bus_addr, data_len,
 569                                                  mss, 0, offload_mode, eop, cq,
 570                                                  0, vlan_tag_insert, vlan_id,
 571                                                  0);
 572
 573                                 *desc_p = desc_tmp;
 574                                 wq->bufs[head_idx] = tx_pkt;
 575                                 head_idx = enic_ring_incr(desc_count, head_idx);
 576                                 wq_desc_avail--;
 577                         }
 578                 }
 579         }
 580  post:
 581         rte_wmb();
 582         iowrite32_relaxed(head_idx, &wq->ctrl->posted_index);
 583  done:
 584         wq->ring.desc_avail = wq_desc_avail;
 585         wq->head_idx = head_idx;
 586
 587         return index;
 588 }
 589
 590 static void enqueue_simple_pkts(struct rte_mbuf **pkts,
 591                                 struct wq_enet_desc *desc,
 592                                 uint16_t n,
 593                                 struct enic *enic)
 594 {
 595         struct rte_mbuf *p;
 596         uint16_t mss;
 597
 598         while (n) {
 599                 n--;
 600                 p = *pkts++;
 601                 desc->address = p->buf_iova + p->data_off;
 602                 desc->length = p->pkt_len;
 603                 /* VLAN insert */
 604                 desc->vlan_tag = p->vlan_tci;
 605                 desc->header_length_flags &=
 606                         ((1 << WQ_ENET_FLAGS_EOP_SHIFT) |
 607                          (1 << WQ_ENET_FLAGS_CQ_ENTRY_SHIFT));
 608                 if (p->ol_flags & PKT_TX_VLAN) {
 609                         desc->header_length_flags |=
 610                                 1 << WQ_ENET_FLAGS_VLAN_TAG_INSERT_SHIFT;
 611                 }
 612                 /*
 613                  * Checksum offload. We use WQ_ENET_OFFLOAD_MODE_CSUM, which
 614                  * is 0, so no need to set offload_mode.
 615                  */
 616                 mss = 0;
 617                 if (p->ol_flags & PKT_TX_IP_CKSUM)
 618                         mss |= ENIC_CALC_IP_CKSUM << WQ_ENET_MSS_SHIFT;
 619                 if (p->ol_flags & PKT_TX_L4_MASK)
 620                         mss |= ENIC_CALC_TCP_UDP_CKSUM << WQ_ENET_MSS_SHIFT;
 621                 desc->mss_loopback = mss;
 622
 623                 /*
 624                  * The app should not send oversized
 625                  * packets. tx_pkt_prepare includes a check as
 626                  * well. But some apps ignore the device max size and
 627                  * tx_pkt_prepare. Oversized packets cause WQ errrors
 628                  * and the NIC ends up disabling the whole WQ. So
 629                  * truncate packets..
 630                  */
 631                 if (unlikely(p->pkt_len > ENIC_TX_MAX_PKT_SIZE)) {
 632                         desc->length = ENIC_TX_MAX_PKT_SIZE;
 633                         rte_atomic64_inc(&enic->soft_stats.tx_oversized);
 634                 }
 635                 desc++;
 636         }
 637 }
 638
 639 uint16_t enic_simple_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 640                                uint16_t nb_pkts)
 641 {
 642         unsigned int head_idx, desc_count;
 643         struct wq_enet_desc *desc;
 644         struct vnic_wq *wq;
 645         struct enic *enic;
 646         uint16_t rem, n;
 647
 648         wq = (struct vnic_wq *)tx_queue;
 649         enic = vnic_dev_priv(wq->vdev);
 650         enic_cleanup_wq(enic, wq);
 651         /* Will enqueue this many packets in this call */
 652         nb_pkts = RTE_MIN(nb_pkts, wq->ring.desc_avail);
 653         if (nb_pkts == 0)
 654                 return 0;
 655
 656         head_idx = wq->head_idx;
 657         desc_count = wq->ring.desc_count;
 658
 659         /* Descriptors until the end of the ring */
 660         n = desc_count - head_idx;
 661         n = RTE_MIN(nb_pkts, n);
 662
 663         /* Save mbuf pointers to free later */
 664         memcpy(wq->bufs + head_idx, tx_pkts, sizeof(struct rte_mbuf *) * n);
 665
 666         /* Enqueue until the ring end */
 667         rem = nb_pkts - n;
 668         desc = ((struct wq_enet_desc *)wq->ring.descs) + head_idx;
 669         enqueue_simple_pkts(tx_pkts, desc, n, enic);
 670
 671         /* Wrap to the start of the ring */
 672         if (rem) {
 673                 tx_pkts += n;
 674                 memcpy(wq->bufs, tx_pkts, sizeof(struct rte_mbuf *) * rem);
 675                 desc = (struct wq_enet_desc *)wq->ring.descs;
 676                 enqueue_simple_pkts(tx_pkts, desc, rem, enic);
 677         }
 678         rte_wmb();
 679
 680         /* Update head_idx and desc_avail */
 681         wq->ring.desc_avail -= nb_pkts;
 682         head_idx += nb_pkts;
 683         if (head_idx >= desc_count)
 684                 head_idx -= desc_count;
 685         wq->head_idx = head_idx;
 686         iowrite32_relaxed(head_idx, &wq->ctrl->posted_index);
 687         return nb_pkts;
 688 }