drivers/infiniband/hw/hfi1/uc.c

   1 /*
   2  * Copyright(c) 2015, 2016 Intel Corporation.
   3  *
   4  * This file is provided under a dual BSD/GPLv2 license.  When using or
   5  * redistributing this file, you may do so under either license.
   6  *
   7  * GPL LICENSE SUMMARY
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * BSD LICENSE
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted provided that the following conditions
  22  * are met:
  23  *
  24  *  - Redistributions of source code must retain the above copyright
  25  *    notice, this list of conditions and the following disclaimer.
  26  *  - Redistributions in binary form must reproduce the above copyright
  27  *    notice, this list of conditions and the following disclaimer in
  28  *    the documentation and/or other materials provided with the
  29  *    distribution.
  30  *  - Neither the name of Intel Corporation nor the names of its
  31  *    contributors may be used to endorse or promote products derived
  32  *    from this software without specific prior written permission.
  33  *
  34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  45  *
  46  */
  47
  48 #include "hfi.h"
  49 #include "verbs_txreq.h"
  50 #include "qp.h"
  51
  52 /* cut down ridiculously long IB macro names */
  53 #define OP(x) UC_OP(x)
  54
  55 /**
  56  * hfi1_make_uc_req - construct a request packet (SEND, RDMA write)
  57  * @qp: a pointer to the QP
  58  *
  59  * Assume s_lock is held.
  60  *
  61  * Return 1 if constructed; otherwise, return 0.
  62  */
  63 int hfi1_make_uc_req(struct rvt_qp *qp, struct hfi1_pkt_state *ps)
  64 {
  65         struct hfi1_qp_priv *priv = qp->priv;
  66         struct ib_other_headers *ohdr;
  67         struct rvt_swqe *wqe;
  68         u32 hwords;
  69         u32 bth0 = 0;
  70         u32 len;
  71         u32 pmtu = qp->pmtu;
  72         int middle = 0;
  73
  74         ps->s_txreq = get_txreq(ps->dev, qp);
  75         if (IS_ERR(ps->s_txreq))
  76                 goto bail_no_tx;
  77
  78         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
  79                 if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
  80                         goto bail;
  81                 /* We are in the error state, flush the work request. */
  82                 smp_read_barrier_depends(); /* see post_one_send() */
  83                 if (qp->s_last == READ_ONCE(qp->s_head))
  84                         goto bail;
  85                 /* If DMAs are in progress, we can't flush immediately. */
  86                 if (iowait_sdma_pending(&priv->s_iowait)) {
  87                         qp->s_flags |= RVT_S_WAIT_DMA;
  88                         goto bail;
  89                 }
  90                 clear_ahg(qp);
  91                 wqe = rvt_get_swqe_ptr(qp, qp->s_last);
  92                 hfi1_send_complete(qp, wqe, IB_WC_WR_FLUSH_ERR);
  93                 goto done_free_tx;
  94         }
  95
  96         if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
  97                 /* header size in 32-bit words LRH+BTH = (8+12)/4. */
  98                 hwords = 5;
  99                 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
 100                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
 101                 else
 102                         ohdr = &ps->s_txreq->phdr.hdr.ibh.u.oth;
 103         } else {
 104                 /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
 105                 hwords = 7;
 106                 if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
 107                     (hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))))
 108                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
 109                 else
 110                         ohdr = &ps->s_txreq->phdr.hdr.opah.u.oth;
 111         }
 112
 113         /* Get the next send request. */
 114         wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
 115         qp->s_wqe = NULL;
 116         switch (qp->s_state) {
 117         default:
 118                 if (!(ib_rvt_state_ops[qp->state] &
 119                     RVT_PROCESS_NEXT_SEND_OK))
 120                         goto bail;
 121                 /* Check if send work queue is empty. */
 122                 smp_read_barrier_depends(); /* see post_one_send() */
 123                 if (qp->s_cur == READ_ONCE(qp->s_head)) {
 124                         clear_ahg(qp);
 125                         goto bail;
 126                 }
 127                 /*
 128                  * Local operations are processed immediately
 129                  * after all prior requests have completed.
 130                  */
 131                 if (wqe->wr.opcode == IB_WR_REG_MR ||
 132                     wqe->wr.opcode == IB_WR_LOCAL_INV) {
 133                         int local_ops = 0;
 134                         int err = 0;
 135
 136                         if (qp->s_last != qp->s_cur)
 137                                 goto bail;
 138                         if (++qp->s_cur == qp->s_size)
 139                                 qp->s_cur = 0;
 140                         if (!(wqe->wr.send_flags & RVT_SEND_COMPLETION_ONLY)) {
 141                                 err = rvt_invalidate_rkey(
 142                                         qp, wqe->wr.ex.invalidate_rkey);
 143                                 local_ops = 1;
 144                         }
 145                         hfi1_send_complete(qp, wqe, err ? IB_WC_LOC_PROT_ERR
 146                                                         : IB_WC_SUCCESS);
 147                         if (local_ops)
 148                                 atomic_dec(&qp->local_ops_pending);
 149                         goto done_free_tx;
 150                 }
 151                 /*
 152                  * Start a new request.
 153                  */
 154                 qp->s_psn = wqe->psn;
 155                 qp->s_sge.sge = wqe->sg_list[0];
 156                 qp->s_sge.sg_list = wqe->sg_list + 1;
 157                 qp->s_sge.num_sge = wqe->wr.num_sge;
 158                 qp->s_sge.total_len = wqe->length;
 159                 len = wqe->length;
 160                 qp->s_len = len;
 161                 switch (wqe->wr.opcode) {
 162                 case IB_WR_SEND:
 163                 case IB_WR_SEND_WITH_IMM:
 164                         if (len > pmtu) {
 165                                 qp->s_state = OP(SEND_FIRST);
 166                                 len = pmtu;
 167                                 break;
 168                         }
 169                         if (wqe->wr.opcode == IB_WR_SEND) {
 170                                 qp->s_state = OP(SEND_ONLY);
 171                         } else {
 172                                 qp->s_state =
 173                                         OP(SEND_ONLY_WITH_IMMEDIATE);
 174                                 /* Immediate data comes after the BTH */
 175                                 ohdr->u.imm_data = wqe->wr.ex.imm_data;
 176                                 hwords += 1;
 177                         }
 178                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 179                                 bth0 |= IB_BTH_SOLICITED;
 180                         qp->s_wqe = wqe;
 181                         if (++qp->s_cur >= qp->s_size)
 182                                 qp->s_cur = 0;
 183                         break;
 184
 185                 case IB_WR_RDMA_WRITE:
 186                 case IB_WR_RDMA_WRITE_WITH_IMM:
 187                         ohdr->u.rc.reth.vaddr =
 188                                 cpu_to_be64(wqe->rdma_wr.remote_addr);
 189                         ohdr->u.rc.reth.rkey =
 190                                 cpu_to_be32(wqe->rdma_wr.rkey);
 191                         ohdr->u.rc.reth.length = cpu_to_be32(len);
 192                         hwords += sizeof(struct ib_reth) / 4;
 193                         if (len > pmtu) {
 194                                 qp->s_state = OP(RDMA_WRITE_FIRST);
 195                                 len = pmtu;
 196                                 break;
 197                         }
 198                         if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
 199                                 qp->s_state = OP(RDMA_WRITE_ONLY);
 200                         } else {
 201                                 qp->s_state =
 202                                         OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
 203                                 /* Immediate data comes after the RETH */
 204                                 ohdr->u.rc.imm_data = wqe->wr.ex.imm_data;
 205                                 hwords += 1;
 206                                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 207                                         bth0 |= IB_BTH_SOLICITED;
 208                         }
 209                         qp->s_wqe = wqe;
 210                         if (++qp->s_cur >= qp->s_size)
 211                                 qp->s_cur = 0;
 212                         break;
 213
 214                 default:
 215                         goto bail;
 216                 }
 217                 break;
 218
 219         case OP(SEND_FIRST):
 220                 qp->s_state = OP(SEND_MIDDLE);
 221                 /* FALLTHROUGH */
 222         case OP(SEND_MIDDLE):
 223                 len = qp->s_len;
 224                 if (len > pmtu) {
 225                         len = pmtu;
 226                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
 227                         break;
 228                 }
 229                 if (wqe->wr.opcode == IB_WR_SEND) {
 230                         qp->s_state = OP(SEND_LAST);
 231                 } else {
 232                         qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
 233                         /* Immediate data comes after the BTH */
 234                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
 235                         hwords += 1;
 236                 }
 237                 if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 238                         bth0 |= IB_BTH_SOLICITED;
 239                 qp->s_wqe = wqe;
 240                 if (++qp->s_cur >= qp->s_size)
 241                         qp->s_cur = 0;
 242                 break;
 243
 244         case OP(RDMA_WRITE_FIRST):
 245                 qp->s_state = OP(RDMA_WRITE_MIDDLE);
 246                 /* FALLTHROUGH */
 247         case OP(RDMA_WRITE_MIDDLE):
 248                 len = qp->s_len;
 249                 if (len > pmtu) {
 250                         len = pmtu;
 251                         middle = HFI1_CAP_IS_KSET(SDMA_AHG);
 252                         break;
 253                 }
 254                 if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
 255                         qp->s_state = OP(RDMA_WRITE_LAST);
 256                 } else {
 257                         qp->s_state =
 258                                 OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
 259                         /* Immediate data comes after the BTH */
 260                         ohdr->u.imm_data = wqe->wr.ex.imm_data;
 261                         hwords += 1;
 262                         if (wqe->wr.send_flags & IB_SEND_SOLICITED)
 263                                 bth0 |= IB_BTH_SOLICITED;
 264                 }
 265                 qp->s_wqe = wqe;
 266                 if (++qp->s_cur >= qp->s_size)
 267                         qp->s_cur = 0;
 268                 break;
 269         }
 270         qp->s_len -= len;
 271         ps->s_txreq->hdr_dwords = hwords;
 272         ps->s_txreq->sde = priv->s_sde;
 273         ps->s_txreq->ss = &qp->s_sge;
 274         ps->s_txreq->s_cur_size = len;
 275         hfi1_make_ruc_header(qp, ohdr, bth0 | (qp->s_state << 24),
 276                              mask_psn(qp->s_psn++), middle, ps);
 277         return 1;
 278
 279 done_free_tx:
 280         hfi1_put_txreq(ps->s_txreq);
 281         ps->s_txreq = NULL;
 282         return 1;
 283
 284 bail:
 285         hfi1_put_txreq(ps->s_txreq);
 286
 287 bail_no_tx:
 288         ps->s_txreq = NULL;
 289         qp->s_flags &= ~RVT_S_BUSY;
 290         return 0;
 291 }
 292
 293 /**
 294  * hfi1_uc_rcv - handle an incoming UC packet
 295  * @ibp: the port the packet came in on
 296  * @hdr: the header of the packet
 297  * @rcv_flags: flags relevant to rcv processing
 298  * @data: the packet data
 299  * @tlen: the length of the packet
 300  * @qp: the QP for this packet.
 301  *
 302  * This is called from qp_rcv() to process an incoming UC packet
 303  * for the given QP.
 304  * Called at interrupt level.
 305  */
 306 void hfi1_uc_rcv(struct hfi1_packet *packet)
 307 {
 308         struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
 309         void *data = packet->payload;
 310         u32 tlen = packet->tlen;
 311         struct rvt_qp *qp = packet->qp;
 312         struct ib_other_headers *ohdr = packet->ohdr;
 313         u32 opcode = packet->opcode;
 314         u32 hdrsize = packet->hlen;
 315         u32 psn;
 316         u32 pad = packet->pad;
 317         struct ib_wc wc;
 318         u32 pmtu = qp->pmtu;
 319         struct ib_reth *reth;
 320         int ret;
 321         u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
 322
 323         if (hfi1_ruc_check_hdr(ibp, packet))
 324                 return;
 325
 326         process_ecn(qp, packet, true);
 327
 328         psn = ib_bth_get_psn(ohdr);
 329         /* Compare the PSN verses the expected PSN. */
 330         if (unlikely(cmp_psn(psn, qp->r_psn) != 0)) {
 331                 /*
 332                  * Handle a sequence error.
 333                  * Silently drop any current message.
 334                  */
 335                 qp->r_psn = psn;
 336 inv:
 337                 if (qp->r_state == OP(SEND_FIRST) ||
 338                     qp->r_state == OP(SEND_MIDDLE)) {
 339                         set_bit(RVT_R_REWIND_SGE, &qp->r_aflags);
 340                         qp->r_sge.num_sge = 0;
 341                 } else {
 342                         rvt_put_ss(&qp->r_sge);
 343                 }
 344                 qp->r_state = OP(SEND_LAST);
 345                 switch (opcode) {
 346                 case OP(SEND_FIRST):
 347                 case OP(SEND_ONLY):
 348                 case OP(SEND_ONLY_WITH_IMMEDIATE):
 349                         goto send_first;
 350
 351                 case OP(RDMA_WRITE_FIRST):
 352                 case OP(RDMA_WRITE_ONLY):
 353                 case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
 354                         goto rdma_first;
 355
 356                 default:
 357                         goto drop;
 358                 }
 359         }
 360
 361         /* Check for opcode sequence errors. */
 362         switch (qp->r_state) {
 363         case OP(SEND_FIRST):
 364         case OP(SEND_MIDDLE):
 365                 if (opcode == OP(SEND_MIDDLE) ||
 366                     opcode == OP(SEND_LAST) ||
 367                     opcode == OP(SEND_LAST_WITH_IMMEDIATE))
 368                         break;
 369                 goto inv;
 370
 371         case OP(RDMA_WRITE_FIRST):
 372         case OP(RDMA_WRITE_MIDDLE):
 373                 if (opcode == OP(RDMA_WRITE_MIDDLE) ||
 374                     opcode == OP(RDMA_WRITE_LAST) ||
 375                     opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
 376                         break;
 377                 goto inv;
 378
 379         default:
 380                 if (opcode == OP(SEND_FIRST) ||
 381                     opcode == OP(SEND_ONLY) ||
 382                     opcode == OP(SEND_ONLY_WITH_IMMEDIATE) ||
 383                     opcode == OP(RDMA_WRITE_FIRST) ||
 384                     opcode == OP(RDMA_WRITE_ONLY) ||
 385                     opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
 386                         break;
 387                 goto inv;
 388         }
 389
 390         if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
 391                 rvt_comm_est(qp);
 392
 393         /* OK, process the packet. */
 394         switch (opcode) {
 395         case OP(SEND_FIRST):
 396         case OP(SEND_ONLY):
 397         case OP(SEND_ONLY_WITH_IMMEDIATE):
 398 send_first:
 399                 if (test_and_clear_bit(RVT_R_REWIND_SGE, &qp->r_aflags)) {
 400                         qp->r_sge = qp->s_rdma_read_sge;
 401                 } else {
 402                         ret = hfi1_rvt_get_rwqe(qp, 0);
 403                         if (ret < 0)
 404                                 goto op_err;
 405                         if (!ret)
 406                                 goto drop;
 407                         /*
 408                          * qp->s_rdma_read_sge will be the owner
 409                          * of the mr references.
 410                          */
 411                         qp->s_rdma_read_sge = qp->r_sge;
 412                 }
 413                 qp->r_rcv_len = 0;
 414                 if (opcode == OP(SEND_ONLY))
 415                         goto no_immediate_data;
 416                 else if (opcode == OP(SEND_ONLY_WITH_IMMEDIATE))
 417                         goto send_last_imm;
 418                 /* FALLTHROUGH */
 419         case OP(SEND_MIDDLE):
 420                 /* Check for invalid length PMTU or posted rwqe len. */
 421                 /*
 422                  * There will be no padding for 9B packet but 16B packets
 423                  * will come in with some padding since we always add
 424                  * CRC and LT bytes which will need to be flit aligned
 425                  */
 426                 if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
 427                         goto rewind;
 428                 qp->r_rcv_len += pmtu;
 429                 if (unlikely(qp->r_rcv_len > qp->r_len))
 430                         goto rewind;
 431                 hfi1_copy_sge(&qp->r_sge, data, pmtu, false, false);
 432                 break;
 433
 434         case OP(SEND_LAST_WITH_IMMEDIATE):
 435 send_last_imm:
 436                 wc.ex.imm_data = ohdr->u.imm_data;
 437                 wc.wc_flags = IB_WC_WITH_IMM;
 438                 goto send_last;
 439         case OP(SEND_LAST):
 440 no_immediate_data:
 441                 wc.ex.imm_data = 0;
 442                 wc.wc_flags = 0;
 443 send_last:
 444                 /* Check for invalid length. */
 445                 /* LAST len should be >= 1 */
 446                 if (unlikely(tlen < (hdrsize + extra_bytes)))
 447                         goto rewind;
 448                 /* Don't count the CRC. */
 449                 tlen -= (hdrsize + extra_bytes);
 450                 wc.byte_len = tlen + qp->r_rcv_len;
 451                 if (unlikely(wc.byte_len > qp->r_len))
 452                         goto rewind;
 453                 wc.opcode = IB_WC_RECV;
 454                 hfi1_copy_sge(&qp->r_sge, data, tlen, false, false);
 455                 rvt_put_ss(&qp->s_rdma_read_sge);
 456 last_imm:
 457                 wc.wr_id = qp->r_wr_id;
 458                 wc.status = IB_WC_SUCCESS;
 459                 wc.qp = &qp->ibqp;
 460                 wc.src_qp = qp->remote_qpn;
 461                 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
 462                 /*
 463                  * It seems that IB mandates the presence of an SL in a
 464                  * work completion only for the UD transport (see section
 465                  * 11.4.2 of IBTA Vol. 1).
 466                  *
 467                  * However, the way the SL is chosen below is consistent
 468                  * with the way that IB/qib works and is trying avoid
 469                  * introducing incompatibilities.
 470                  *
 471                  * See also OPA Vol. 1, section 9.7.6, and table 9-17.
 472                  */
 473                 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
 474                 /* zero fields that are N/A */
 475                 wc.vendor_err = 0;
 476                 wc.pkey_index = 0;
 477                 wc.dlid_path_bits = 0;
 478                 wc.port_num = 0;
 479                 /* Signal completion event if the solicited bit is set. */
 480                 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
 481                              ib_bth_is_solicited(ohdr));
 482                 break;
 483
 484         case OP(RDMA_WRITE_FIRST):
 485         case OP(RDMA_WRITE_ONLY):
 486         case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE): /* consume RWQE */
 487 rdma_first:
 488                 if (unlikely(!(qp->qp_access_flags &
 489                                IB_ACCESS_REMOTE_WRITE))) {
 490                         goto drop;
 491                 }
 492                 reth = &ohdr->u.rc.reth;
 493                 qp->r_len = be32_to_cpu(reth->length);
 494                 qp->r_rcv_len = 0;
 495                 qp->r_sge.sg_list = NULL;
 496                 if (qp->r_len != 0) {
 497                         u32 rkey = be32_to_cpu(reth->rkey);
 498                         u64 vaddr = be64_to_cpu(reth->vaddr);
 499                         int ok;
 500
 501                         /* Check rkey */
 502                         ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len,
 503                                          vaddr, rkey, IB_ACCESS_REMOTE_WRITE);
 504                         if (unlikely(!ok))
 505                                 goto drop;
 506                         qp->r_sge.num_sge = 1;
 507                 } else {
 508                         qp->r_sge.num_sge = 0;
 509                         qp->r_sge.sge.mr = NULL;
 510                         qp->r_sge.sge.vaddr = NULL;
 511                         qp->r_sge.sge.length = 0;
 512                         qp->r_sge.sge.sge_length = 0;
 513                 }
 514                 if (opcode == OP(RDMA_WRITE_ONLY)) {
 515                         goto rdma_last;
 516                 } else if (opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE)) {
 517                         wc.ex.imm_data = ohdr->u.rc.imm_data;
 518                         goto rdma_last_imm;
 519                 }
 520                 /* FALLTHROUGH */
 521         case OP(RDMA_WRITE_MIDDLE):
 522                 /* Check for invalid length PMTU or posted rwqe len. */
 523                 if (unlikely(tlen != (hdrsize + pmtu + 4)))
 524                         goto drop;
 525                 qp->r_rcv_len += pmtu;
 526                 if (unlikely(qp->r_rcv_len > qp->r_len))
 527                         goto drop;
 528                 hfi1_copy_sge(&qp->r_sge, data, pmtu, true, false);
 529                 break;
 530
 531         case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
 532                 wc.ex.imm_data = ohdr->u.imm_data;
 533 rdma_last_imm:
 534                 wc.wc_flags = IB_WC_WITH_IMM;
 535
 536                 /* Check for invalid length. */
 537                 /* LAST len should be >= 1 */
 538                 if (unlikely(tlen < (hdrsize + pad + 4)))
 539                         goto drop;
 540                 /* Don't count the CRC. */
 541                 tlen -= (hdrsize + extra_bytes);
 542                 if (unlikely(tlen + qp->r_rcv_len != qp->r_len))
 543                         goto drop;
 544                 if (test_and_clear_bit(RVT_R_REWIND_SGE, &qp->r_aflags)) {
 545                         rvt_put_ss(&qp->s_rdma_read_sge);
 546                 } else {
 547                         ret = hfi1_rvt_get_rwqe(qp, 1);
 548                         if (ret < 0)
 549                                 goto op_err;
 550                         if (!ret)
 551                                 goto drop;
 552                 }
 553                 wc.byte_len = qp->r_len;
 554                 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
 555                 hfi1_copy_sge(&qp->r_sge, data, tlen, true, false);
 556                 rvt_put_ss(&qp->r_sge);
 557                 goto last_imm;
 558
 559         case OP(RDMA_WRITE_LAST):
 560 rdma_last:
 561                 /* Check for invalid length. */
 562                 /* LAST len should be >= 1 */
 563                 if (unlikely(tlen < (hdrsize + pad + 4)))
 564                         goto drop;
 565                 /* Don't count the CRC. */
 566                 tlen -= (hdrsize + extra_bytes);
 567                 if (unlikely(tlen + qp->r_rcv_len != qp->r_len))
 568                         goto drop;
 569                 hfi1_copy_sge(&qp->r_sge, data, tlen, true, false);
 570                 rvt_put_ss(&qp->r_sge);
 571                 break;
 572
 573         default:
 574                 /* Drop packet for unknown opcodes. */
 575                 goto drop;
 576         }
 577         qp->r_psn++;
 578         qp->r_state = opcode;
 579         return;
 580
 581 rewind:
 582         set_bit(RVT_R_REWIND_SGE, &qp->r_aflags);
 583         qp->r_sge.num_sge = 0;
 584 drop:
 585         ibp->rvp.n_pkt_drops++;
 586         return;
 587
 588 op_err:
 589         rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
 590 }