drivers/infiniband/hw/hfi1/ruc.c

   1 /*
   2  * Copyright(c) 2015 - 2017 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 <linux/spinlock.h>
  49
  50 #include "hfi.h"
  51 #include "mad.h"
  52 #include "qp.h"
  53 #include "verbs_txreq.h"
  54 #include "trace.h"
  55
  56 /*
  57  * Validate a RWQE and fill in the SGE state.
  58  * Return 1 if OK.
  59  */
  60 static int init_sge(struct rvt_qp *qp, struct rvt_rwqe *wqe)
  61 {
  62         int i, j, ret;
  63         struct ib_wc wc;
  64         struct rvt_lkey_table *rkt;
  65         struct rvt_pd *pd;
  66         struct rvt_sge_state *ss;
  67
  68         rkt = &to_idev(qp->ibqp.device)->rdi.lkey_table;
  69         pd = ibpd_to_rvtpd(qp->ibqp.srq ? qp->ibqp.srq->pd : qp->ibqp.pd);
  70         ss = &qp->r_sge;
  71         ss->sg_list = qp->r_sg_list;
  72         qp->r_len = 0;
  73         for (i = j = 0; i < wqe->num_sge; i++) {
  74                 if (wqe->sg_list[i].length == 0)
  75                         continue;
  76                 /* Check LKEY */
  77                 ret = rvt_lkey_ok(rkt, pd, j ? &ss->sg_list[j - 1] : &ss->sge,
  78                                   NULL, &wqe->sg_list[i],
  79                                   IB_ACCESS_LOCAL_WRITE);
  80                 if (unlikely(ret <= 0))
  81                         goto bad_lkey;
  82                 qp->r_len += wqe->sg_list[i].length;
  83                 j++;
  84         }
  85         ss->num_sge = j;
  86         ss->total_len = qp->r_len;
  87         ret = 1;
  88         goto bail;
  89
  90 bad_lkey:
  91         while (j) {
  92                 struct rvt_sge *sge = --j ? &ss->sg_list[j - 1] : &ss->sge;
  93
  94                 rvt_put_mr(sge->mr);
  95         }
  96         ss->num_sge = 0;
  97         memset(&wc, 0, sizeof(wc));
  98         wc.wr_id = wqe->wr_id;
  99         wc.status = IB_WC_LOC_PROT_ERR;
 100         wc.opcode = IB_WC_RECV;
 101         wc.qp = &qp->ibqp;
 102         /* Signal solicited completion event. */
 103         rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc, 1);
 104         ret = 0;
 105 bail:
 106         return ret;
 107 }
 108
 109 /**
 110  * hfi1_rvt_get_rwqe - copy the next RWQE into the QP's RWQE
 111  * @qp: the QP
 112  * @wr_id_only: update qp->r_wr_id only, not qp->r_sge
 113  *
 114  * Return -1 if there is a local error, 0 if no RWQE is available,
 115  * otherwise return 1.
 116  *
 117  * Can be called from interrupt level.
 118  */
 119 int hfi1_rvt_get_rwqe(struct rvt_qp *qp, int wr_id_only)
 120 {
 121         unsigned long flags;
 122         struct rvt_rq *rq;
 123         struct rvt_rwq *wq;
 124         struct rvt_srq *srq;
 125         struct rvt_rwqe *wqe;
 126         void (*handler)(struct ib_event *, void *);
 127         u32 tail;
 128         int ret;
 129
 130         if (qp->ibqp.srq) {
 131                 srq = ibsrq_to_rvtsrq(qp->ibqp.srq);
 132                 handler = srq->ibsrq.event_handler;
 133                 rq = &srq->rq;
 134         } else {
 135                 srq = NULL;
 136                 handler = NULL;
 137                 rq = &qp->r_rq;
 138         }
 139
 140         spin_lock_irqsave(&rq->lock, flags);
 141         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) {
 142                 ret = 0;
 143                 goto unlock;
 144         }
 145
 146         wq = rq->wq;
 147         tail = wq->tail;
 148         /* Validate tail before using it since it is user writable. */
 149         if (tail >= rq->size)
 150                 tail = 0;
 151         if (unlikely(tail == wq->head)) {
 152                 ret = 0;
 153                 goto unlock;
 154         }
 155         /* Make sure entry is read after head index is read. */
 156         smp_rmb();
 157         wqe = rvt_get_rwqe_ptr(rq, tail);
 158         /*
 159          * Even though we update the tail index in memory, the verbs
 160          * consumer is not supposed to post more entries until a
 161          * completion is generated.
 162          */
 163         if (++tail >= rq->size)
 164                 tail = 0;
 165         wq->tail = tail;
 166         if (!wr_id_only && !init_sge(qp, wqe)) {
 167                 ret = -1;
 168                 goto unlock;
 169         }
 170         qp->r_wr_id = wqe->wr_id;
 171
 172         ret = 1;
 173         set_bit(RVT_R_WRID_VALID, &qp->r_aflags);
 174         if (handler) {
 175                 u32 n;
 176
 177                 /*
 178                  * Validate head pointer value and compute
 179                  * the number of remaining WQEs.
 180                  */
 181                 n = wq->head;
 182                 if (n >= rq->size)
 183                         n = 0;
 184                 if (n < tail)
 185                         n += rq->size - tail;
 186                 else
 187                         n -= tail;
 188                 if (n < srq->limit) {
 189                         struct ib_event ev;
 190
 191                         srq->limit = 0;
 192                         spin_unlock_irqrestore(&rq->lock, flags);
 193                         ev.device = qp->ibqp.device;
 194                         ev.element.srq = qp->ibqp.srq;
 195                         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
 196                         handler(&ev, srq->ibsrq.srq_context);
 197                         goto bail;
 198                 }
 199         }
 200 unlock:
 201         spin_unlock_irqrestore(&rq->lock, flags);
 202 bail:
 203         return ret;
 204 }
 205
 206 static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
 207 {
 208         return (gid->global.interface_id == id &&
 209                 (gid->global.subnet_prefix == gid_prefix ||
 210                  gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
 211 }
 212
 213 /*
 214  *
 215  * This should be called with the QP r_lock held.
 216  *
 217  * The s_lock will be acquired around the hfi1_migrate_qp() call.
 218  */
 219 int hfi1_ruc_check_hdr(struct hfi1_ibport *ibp, struct hfi1_packet *packet)
 220 {
 221         __be64 guid;
 222         unsigned long flags;
 223         struct rvt_qp *qp = packet->qp;
 224         u8 sc5 = ibp->sl_to_sc[rdma_ah_get_sl(&qp->remote_ah_attr)];
 225         u32 dlid = packet->dlid;
 226         u32 slid = packet->slid;
 227         u32 sl = packet->sl;
 228         int migrated;
 229         u32 bth0, bth1;
 230         u16 pkey;
 231
 232         bth0 = be32_to_cpu(packet->ohdr->bth[0]);
 233         bth1 = be32_to_cpu(packet->ohdr->bth[1]);
 234         if (packet->etype == RHF_RCV_TYPE_BYPASS) {
 235                 pkey = hfi1_16B_get_pkey(packet->hdr);
 236                 migrated = bth1 & OPA_BTH_MIG_REQ;
 237         } else {
 238                 pkey = ib_bth_get_pkey(packet->ohdr);
 239                 migrated = bth0 & IB_BTH_MIG_REQ;
 240         }
 241
 242         if (qp->s_mig_state == IB_MIG_ARMED && migrated) {
 243                 if (!packet->grh) {
 244                         if ((rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
 245                              IB_AH_GRH) &&
 246                             (packet->etype != RHF_RCV_TYPE_BYPASS))
 247                                 return 1;
 248                 } else {
 249                         const struct ib_global_route *grh;
 250
 251                         if (!(rdma_ah_get_ah_flags(&qp->alt_ah_attr) &
 252                               IB_AH_GRH))
 253                                 return 1;
 254                         grh = rdma_ah_read_grh(&qp->alt_ah_attr);
 255                         guid = get_sguid(ibp, grh->sgid_index);
 256                         if (!gid_ok(&packet->grh->dgid, ibp->rvp.gid_prefix,
 257                                     guid))
 258                                 return 1;
 259                         if (!gid_ok(
 260                                 &packet->grh->sgid,
 261                                 grh->dgid.global.subnet_prefix,
 262                                 grh->dgid.global.interface_id))
 263                                 return 1;
 264                 }
 265                 if (unlikely(rcv_pkey_check(ppd_from_ibp(ibp), pkey,
 266                                             sc5, slid))) {
 267                         hfi1_bad_pkey(ibp, pkey, sl, 0, qp->ibqp.qp_num,
 268                                       slid, dlid);
 269                         return 1;
 270                 }
 271                 /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
 272                 if (slid != rdma_ah_get_dlid(&qp->alt_ah_attr) ||
 273                     ppd_from_ibp(ibp)->port !=
 274                         rdma_ah_get_port_num(&qp->alt_ah_attr))
 275                         return 1;
 276                 spin_lock_irqsave(&qp->s_lock, flags);
 277                 hfi1_migrate_qp(qp);
 278                 spin_unlock_irqrestore(&qp->s_lock, flags);
 279         } else {
 280                 if (!packet->grh) {
 281                         if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
 282                              IB_AH_GRH) &&
 283                             (packet->etype != RHF_RCV_TYPE_BYPASS))
 284                                 return 1;
 285                 } else {
 286                         const struct ib_global_route *grh;
 287
 288                         if (!(rdma_ah_get_ah_flags(&qp->remote_ah_attr) &
 289                                                    IB_AH_GRH))
 290                                 return 1;
 291                         grh = rdma_ah_read_grh(&qp->remote_ah_attr);
 292                         guid = get_sguid(ibp, grh->sgid_index);
 293                         if (!gid_ok(&packet->grh->dgid, ibp->rvp.gid_prefix,
 294                                     guid))
 295                                 return 1;
 296                         if (!gid_ok(
 297                              &packet->grh->sgid,
 298                              grh->dgid.global.subnet_prefix,
 299                              grh->dgid.global.interface_id))
 300                                 return 1;
 301                 }
 302                 if (unlikely(rcv_pkey_check(ppd_from_ibp(ibp), pkey,
 303                                             sc5, slid))) {
 304                         hfi1_bad_pkey(ibp, pkey, sl, 0, qp->ibqp.qp_num,
 305                                       slid, dlid);
 306                         return 1;
 307                 }
 308                 /* Validate the SLID. See Ch. 9.6.1.5 */
 309                 if ((slid != rdma_ah_get_dlid(&qp->remote_ah_attr)) ||
 310                     ppd_from_ibp(ibp)->port != qp->port_num)
 311                         return 1;
 312                 if (qp->s_mig_state == IB_MIG_REARM && !migrated)
 313                         qp->s_mig_state = IB_MIG_ARMED;
 314         }
 315
 316         return 0;
 317 }
 318
 319 /**
 320  * ruc_loopback - handle UC and RC loopback requests
 321  * @sqp: the sending QP
 322  *
 323  * This is called from hfi1_do_send() to
 324  * forward a WQE addressed to the same HFI.
 325  * Note that although we are single threaded due to the send engine, we still
 326  * have to protect against post_send().  We don't have to worry about
 327  * receive interrupts since this is a connected protocol and all packets
 328  * will pass through here.
 329  */
 330 static void ruc_loopback(struct rvt_qp *sqp)
 331 {
 332         struct hfi1_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
 333         struct rvt_qp *qp;
 334         struct rvt_swqe *wqe;
 335         struct rvt_sge *sge;
 336         unsigned long flags;
 337         struct ib_wc wc;
 338         u64 sdata;
 339         atomic64_t *maddr;
 340         enum ib_wc_status send_status;
 341         bool release;
 342         int ret;
 343         bool copy_last = false;
 344         int local_ops = 0;
 345
 346         rcu_read_lock();
 347
 348         /*
 349          * Note that we check the responder QP state after
 350          * checking the requester's state.
 351          */
 352         qp = rvt_lookup_qpn(ib_to_rvt(sqp->ibqp.device), &ibp->rvp,
 353                             sqp->remote_qpn);
 354
 355         spin_lock_irqsave(&sqp->s_lock, flags);
 356
 357         /* Return if we are already busy processing a work request. */
 358         if ((sqp->s_flags & (RVT_S_BUSY | RVT_S_ANY_WAIT)) ||
 359             !(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_OR_FLUSH_SEND))
 360                 goto unlock;
 361
 362         sqp->s_flags |= RVT_S_BUSY;
 363
 364 again:
 365         smp_read_barrier_depends(); /* see post_one_send() */
 366         if (sqp->s_last == ACCESS_ONCE(sqp->s_head))
 367                 goto clr_busy;
 368         wqe = rvt_get_swqe_ptr(sqp, sqp->s_last);
 369
 370         /* Return if it is not OK to start a new work request. */
 371         if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_NEXT_SEND_OK)) {
 372                 if (!(ib_rvt_state_ops[sqp->state] & RVT_FLUSH_SEND))
 373                         goto clr_busy;
 374                 /* We are in the error state, flush the work request. */
 375                 send_status = IB_WC_WR_FLUSH_ERR;
 376                 goto flush_send;
 377         }
 378
 379         /*
 380          * We can rely on the entry not changing without the s_lock
 381          * being held until we update s_last.
 382          * We increment s_cur to indicate s_last is in progress.
 383          */
 384         if (sqp->s_last == sqp->s_cur) {
 385                 if (++sqp->s_cur >= sqp->s_size)
 386                         sqp->s_cur = 0;
 387         }
 388         spin_unlock_irqrestore(&sqp->s_lock, flags);
 389
 390         if (!qp || !(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) ||
 391             qp->ibqp.qp_type != sqp->ibqp.qp_type) {
 392                 ibp->rvp.n_pkt_drops++;
 393                 /*
 394                  * For RC, the requester would timeout and retry so
 395                  * shortcut the timeouts and just signal too many retries.
 396                  */
 397                 if (sqp->ibqp.qp_type == IB_QPT_RC)
 398                         send_status = IB_WC_RETRY_EXC_ERR;
 399                 else
 400                         send_status = IB_WC_SUCCESS;
 401                 goto serr;
 402         }
 403
 404         memset(&wc, 0, sizeof(wc));
 405         send_status = IB_WC_SUCCESS;
 406
 407         release = true;
 408         sqp->s_sge.sge = wqe->sg_list[0];
 409         sqp->s_sge.sg_list = wqe->sg_list + 1;
 410         sqp->s_sge.num_sge = wqe->wr.num_sge;
 411         sqp->s_len = wqe->length;
 412         switch (wqe->wr.opcode) {
 413         case IB_WR_REG_MR:
 414                 goto send_comp;
 415
 416         case IB_WR_LOCAL_INV:
 417                 if (!(wqe->wr.send_flags & RVT_SEND_COMPLETION_ONLY)) {
 418                         if (rvt_invalidate_rkey(sqp,
 419                                                 wqe->wr.ex.invalidate_rkey))
 420                                 send_status = IB_WC_LOC_PROT_ERR;
 421                         local_ops = 1;
 422                 }
 423                 goto send_comp;
 424
 425         case IB_WR_SEND_WITH_INV:
 426                 if (!rvt_invalidate_rkey(qp, wqe->wr.ex.invalidate_rkey)) {
 427                         wc.wc_flags = IB_WC_WITH_INVALIDATE;
 428                         wc.ex.invalidate_rkey = wqe->wr.ex.invalidate_rkey;
 429                 }
 430                 goto send;
 431
 432         case IB_WR_SEND_WITH_IMM:
 433                 wc.wc_flags = IB_WC_WITH_IMM;
 434                 wc.ex.imm_data = wqe->wr.ex.imm_data;
 435                 /* FALLTHROUGH */
 436         case IB_WR_SEND:
 437 send:
 438                 ret = hfi1_rvt_get_rwqe(qp, 0);
 439                 if (ret < 0)
 440                         goto op_err;
 441                 if (!ret)
 442                         goto rnr_nak;
 443                 if (wqe->length > qp->r_len)
 444                         goto inv_err;
 445                 break;
 446
 447         case IB_WR_RDMA_WRITE_WITH_IMM:
 448                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
 449                         goto inv_err;
 450                 wc.wc_flags = IB_WC_WITH_IMM;
 451                 wc.ex.imm_data = wqe->wr.ex.imm_data;
 452                 ret = hfi1_rvt_get_rwqe(qp, 1);
 453                 if (ret < 0)
 454                         goto op_err;
 455                 if (!ret)
 456                         goto rnr_nak;
 457                 /* skip copy_last set and qp_access_flags recheck */
 458                 goto do_write;
 459         case IB_WR_RDMA_WRITE:
 460                 copy_last = rvt_is_user_qp(qp);
 461                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
 462                         goto inv_err;
 463 do_write:
 464                 if (wqe->length == 0)
 465                         break;
 466                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
 467                                           wqe->rdma_wr.remote_addr,
 468                                           wqe->rdma_wr.rkey,
 469                                           IB_ACCESS_REMOTE_WRITE)))
 470                         goto acc_err;
 471                 qp->r_sge.sg_list = NULL;
 472                 qp->r_sge.num_sge = 1;
 473                 qp->r_sge.total_len = wqe->length;
 474                 break;
 475
 476         case IB_WR_RDMA_READ:
 477                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
 478                         goto inv_err;
 479                 if (unlikely(!rvt_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
 480                                           wqe->rdma_wr.remote_addr,
 481                                           wqe->rdma_wr.rkey,
 482                                           IB_ACCESS_REMOTE_READ)))
 483                         goto acc_err;
 484                 release = false;
 485                 sqp->s_sge.sg_list = NULL;
 486                 sqp->s_sge.num_sge = 1;
 487                 qp->r_sge.sge = wqe->sg_list[0];
 488                 qp->r_sge.sg_list = wqe->sg_list + 1;
 489                 qp->r_sge.num_sge = wqe->wr.num_sge;
 490                 qp->r_sge.total_len = wqe->length;
 491                 break;
 492
 493         case IB_WR_ATOMIC_CMP_AND_SWP:
 494         case IB_WR_ATOMIC_FETCH_AND_ADD:
 495                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
 496                         goto inv_err;
 497                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
 498                                           wqe->atomic_wr.remote_addr,
 499                                           wqe->atomic_wr.rkey,
 500                                           IB_ACCESS_REMOTE_ATOMIC)))
 501                         goto acc_err;
 502                 /* Perform atomic OP and save result. */
 503                 maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
 504                 sdata = wqe->atomic_wr.compare_add;
 505                 *(u64 *)sqp->s_sge.sge.vaddr =
 506                         (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
 507                         (u64)atomic64_add_return(sdata, maddr) - sdata :
 508                         (u64)cmpxchg((u64 *)qp->r_sge.sge.vaddr,
 509                                       sdata, wqe->atomic_wr.swap);
 510                 rvt_put_mr(qp->r_sge.sge.mr);
 511                 qp->r_sge.num_sge = 0;
 512                 goto send_comp;
 513
 514         default:
 515                 send_status = IB_WC_LOC_QP_OP_ERR;
 516                 goto serr;
 517         }
 518
 519         sge = &sqp->s_sge.sge;
 520         while (sqp->s_len) {
 521                 u32 len = sqp->s_len;
 522
 523                 if (len > sge->length)
 524                         len = sge->length;
 525                 if (len > sge->sge_length)
 526                         len = sge->sge_length;
 527                 WARN_ON_ONCE(len == 0);
 528                 hfi1_copy_sge(&qp->r_sge, sge->vaddr, len, release, copy_last);
 529                 sge->vaddr += len;
 530                 sge->length -= len;
 531                 sge->sge_length -= len;
 532                 if (sge->sge_length == 0) {
 533                         if (!release)
 534                                 rvt_put_mr(sge->mr);
 535                         if (--sqp->s_sge.num_sge)
 536                                 *sge = *sqp->s_sge.sg_list++;
 537                 } else if (sge->length == 0 && sge->mr->lkey) {
 538                         if (++sge->n >= RVT_SEGSZ) {
 539                                 if (++sge->m >= sge->mr->mapsz)
 540                                         break;
 541                                 sge->n = 0;
 542                         }
 543                         sge->vaddr =
 544                                 sge->mr->map[sge->m]->segs[sge->n].vaddr;
 545                         sge->length =
 546                                 sge->mr->map[sge->m]->segs[sge->n].length;
 547                 }
 548                 sqp->s_len -= len;
 549         }
 550         if (release)
 551                 rvt_put_ss(&qp->r_sge);
 552
 553         if (!test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
 554                 goto send_comp;
 555
 556         if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
 557                 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
 558         else
 559                 wc.opcode = IB_WC_RECV;
 560         wc.wr_id = qp->r_wr_id;
 561         wc.status = IB_WC_SUCCESS;
 562         wc.byte_len = wqe->length;
 563         wc.qp = &qp->ibqp;
 564         wc.src_qp = qp->remote_qpn;
 565         wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr);
 566         wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
 567         wc.port_num = 1;
 568         /* Signal completion event if the solicited bit is set. */
 569         rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
 570                      wqe->wr.send_flags & IB_SEND_SOLICITED);
 571
 572 send_comp:
 573         spin_lock_irqsave(&sqp->s_lock, flags);
 574         ibp->rvp.n_loop_pkts++;
 575 flush_send:
 576         sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
 577         hfi1_send_complete(sqp, wqe, send_status);
 578         if (local_ops) {
 579                 atomic_dec(&sqp->local_ops_pending);
 580                 local_ops = 0;
 581         }
 582         goto again;
 583
 584 rnr_nak:
 585         /* Handle RNR NAK */
 586         if (qp->ibqp.qp_type == IB_QPT_UC)
 587                 goto send_comp;
 588         ibp->rvp.n_rnr_naks++;
 589         /*
 590          * Note: we don't need the s_lock held since the BUSY flag
 591          * makes this single threaded.
 592          */
 593         if (sqp->s_rnr_retry == 0) {
 594                 send_status = IB_WC_RNR_RETRY_EXC_ERR;
 595                 goto serr;
 596         }
 597         if (sqp->s_rnr_retry_cnt < 7)
 598                 sqp->s_rnr_retry--;
 599         spin_lock_irqsave(&sqp->s_lock, flags);
 600         if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_RECV_OK))
 601                 goto clr_busy;
 602         rvt_add_rnr_timer(sqp, qp->r_min_rnr_timer <<
 603                                 IB_AETH_CREDIT_SHIFT);
 604         goto clr_busy;
 605
 606 op_err:
 607         send_status = IB_WC_REM_OP_ERR;
 608         wc.status = IB_WC_LOC_QP_OP_ERR;
 609         goto err;
 610
 611 inv_err:
 612         send_status =
 613                 sqp->ibqp.qp_type == IB_QPT_RC ?
 614                         IB_WC_REM_INV_REQ_ERR :
 615                         IB_WC_SUCCESS;
 616         wc.status = IB_WC_LOC_QP_OP_ERR;
 617         goto err;
 618
 619 acc_err:
 620         send_status = IB_WC_REM_ACCESS_ERR;
 621         wc.status = IB_WC_LOC_PROT_ERR;
 622 err:
 623         /* responder goes to error state */
 624         rvt_rc_error(qp, wc.status);
 625
 626 serr:
 627         spin_lock_irqsave(&sqp->s_lock, flags);
 628         hfi1_send_complete(sqp, wqe, send_status);
 629         if (sqp->ibqp.qp_type == IB_QPT_RC) {
 630                 int lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
 631
 632                 sqp->s_flags &= ~RVT_S_BUSY;
 633                 spin_unlock_irqrestore(&sqp->s_lock, flags);
 634                 if (lastwqe) {
 635                         struct ib_event ev;
 636
 637                         ev.device = sqp->ibqp.device;
 638                         ev.element.qp = &sqp->ibqp;
 639                         ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 640                         sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
 641                 }
 642                 goto done;
 643         }
 644 clr_busy:
 645         sqp->s_flags &= ~RVT_S_BUSY;
 646 unlock:
 647         spin_unlock_irqrestore(&sqp->s_lock, flags);
 648 done:
 649         rcu_read_unlock();
 650 }
 651
 652 /**
 653  * hfi1_make_grh - construct a GRH header
 654  * @ibp: a pointer to the IB port
 655  * @hdr: a pointer to the GRH header being constructed
 656  * @grh: the global route address to send to
 657  * @hwords: size of header after grh being sent in dwords
 658  * @nwords: the number of 32 bit words of data being sent
 659  *
 660  * Return the size of the header in 32 bit words.
 661  */
 662 u32 hfi1_make_grh(struct hfi1_ibport *ibp, struct ib_grh *hdr,
 663                   const struct ib_global_route *grh, u32 hwords, u32 nwords)
 664 {
 665         hdr->version_tclass_flow =
 666                 cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
 667                             (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
 668                             (grh->flow_label << IB_GRH_FLOW_SHIFT));
 669         hdr->paylen = cpu_to_be16((hwords + nwords) << 2);
 670         /* next_hdr is defined by C8-7 in ch. 8.4.1 */
 671         hdr->next_hdr = IB_GRH_NEXT_HDR;
 672         hdr->hop_limit = grh->hop_limit;
 673         /* The SGID is 32-bit aligned. */
 674         hdr->sgid.global.subnet_prefix = ibp->rvp.gid_prefix;
 675         hdr->sgid.global.interface_id =
 676                 grh->sgid_index < HFI1_GUIDS_PER_PORT ?
 677                 get_sguid(ibp, grh->sgid_index) :
 678                 get_sguid(ibp, HFI1_PORT_GUID_INDEX);
 679         hdr->dgid = grh->dgid;
 680
 681         /* GRH header size in 32-bit words. */
 682         return sizeof(struct ib_grh) / sizeof(u32);
 683 }
 684
 685 #define BTH2_OFFSET (offsetof(struct hfi1_sdma_header, \
 686                               hdr.ibh.u.oth.bth[2]) / 4)
 687
 688 /**
 689  * build_ahg - create ahg in s_ahg
 690  * @qp: a pointer to QP
 691  * @npsn: the next PSN for the request/response
 692  *
 693  * This routine handles the AHG by allocating an ahg entry and causing the
 694  * copy of the first middle.
 695  *
 696  * Subsequent middles use the copied entry, editing the
 697  * PSN with 1 or 2 edits.
 698  */
 699 static inline void build_ahg(struct rvt_qp *qp, u32 npsn)
 700 {
 701         struct hfi1_qp_priv *priv = qp->priv;
 702
 703         if (unlikely(qp->s_flags & RVT_S_AHG_CLEAR))
 704                 clear_ahg(qp);
 705         if (!(qp->s_flags & RVT_S_AHG_VALID)) {
 706                 /* first middle that needs copy  */
 707                 if (qp->s_ahgidx < 0)
 708                         qp->s_ahgidx = sdma_ahg_alloc(priv->s_sde);
 709                 if (qp->s_ahgidx >= 0) {
 710                         qp->s_ahgpsn = npsn;
 711                         priv->s_ahg->tx_flags |= SDMA_TXREQ_F_AHG_COPY;
 712                         /* save to protect a change in another thread */
 713                         priv->s_ahg->ahgidx = qp->s_ahgidx;
 714                         qp->s_flags |= RVT_S_AHG_VALID;
 715                 }
 716         } else {
 717                 /* subsequent middle after valid */
 718                 if (qp->s_ahgidx >= 0) {
 719                         priv->s_ahg->tx_flags |= SDMA_TXREQ_F_USE_AHG;
 720                         priv->s_ahg->ahgidx = qp->s_ahgidx;
 721                         priv->s_ahg->ahgcount++;
 722                         priv->s_ahg->ahgdesc[0] =
 723                                 sdma_build_ahg_descriptor(
 724                                         (__force u16)cpu_to_be16((u16)npsn),
 725                                         BTH2_OFFSET,
 726                                         16,
 727                                         16);
 728                         if ((npsn & 0xffff0000) !=
 729                                         (qp->s_ahgpsn & 0xffff0000)) {
 730                                 priv->s_ahg->ahgcount++;
 731                                 priv->s_ahg->ahgdesc[1] =
 732                                         sdma_build_ahg_descriptor(
 733                                                 (__force u16)cpu_to_be16(
 734                                                         (u16)(npsn >> 16)),
 735                                                 BTH2_OFFSET,
 736                                                 0,
 737                                                 16);
 738                         }
 739                 }
 740         }
 741 }
 742
 743 static inline void hfi1_make_ruc_bth(struct rvt_qp *qp,
 744                                      struct ib_other_headers *ohdr,
 745                                      u32 bth0, u32 bth1, u32 bth2)
 746 {
 747         bth1 |= qp->remote_qpn;
 748         ohdr->bth[0] = cpu_to_be32(bth0);
 749         ohdr->bth[1] = cpu_to_be32(bth1);
 750         ohdr->bth[2] = cpu_to_be32(bth2);
 751 }
 752
 753 /**
 754  * hfi1_make_ruc_header_16B - build a 16B header
 755  * @qp: the queue pair
 756  * @ohdr: a pointer to the destination header memory
 757  * @bth0: bth0 passed in from the RC/UC builder
 758  * @bth2: bth2 passed in from the RC/UC builder
 759  * @middle: non zero implies indicates ahg "could" be used
 760  * @ps: the current packet state
 761  *
 762  * This routine may disarm ahg under these situations:
 763  * - packet needs a GRH
 764  * - BECN needed
 765  * - migration state not IB_MIG_MIGRATED
 766  */
 767 static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp,
 768                                             struct ib_other_headers *ohdr,
 769                                             u32 bth0, u32 bth2, int middle,
 770                                             struct hfi1_pkt_state *ps)
 771 {
 772         struct hfi1_qp_priv *priv = qp->priv;
 773         struct hfi1_ibport *ibp = ps->ibp;
 774         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
 775         u32 bth1 = 0;
 776         u32 slid;
 777         u16 pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
 778         u8 l4 = OPA_16B_L4_IB_LOCAL;
 779         u8 extra_bytes = hfi1_get_16b_padding((qp->s_hdrwords << 2),
 780                                    ps->s_txreq->s_cur_size);
 781         u32 nwords = SIZE_OF_CRC + ((ps->s_txreq->s_cur_size +
 782                                  extra_bytes + SIZE_OF_LT) >> 2);
 783         u8 becn = 0;
 784
 785         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
 786             hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))) {
 787                 struct ib_grh *grh;
 788                 struct ib_global_route *grd =
 789                         rdma_ah_retrieve_grh(&qp->remote_ah_attr);
 790                 int hdrwords;
 791
 792                 /*
 793                  * Ensure OPA GIDs are transformed to IB gids
 794                  * before creating the GRH.
 795                  */
 796                 if (grd->sgid_index == OPA_GID_INDEX)
 797                         grd->sgid_index = 0;
 798                 grh = &ps->s_txreq->phdr.hdr.opah.u.l.grh;
 799                 l4 = OPA_16B_L4_IB_GLOBAL;
 800                 hdrwords = qp->s_hdrwords - 4;
 801                 qp->s_hdrwords += hfi1_make_grh(ibp, grh, grd,
 802                                                 hdrwords, nwords);
 803                 middle = 0;
 804         }
 805
 806         if (qp->s_mig_state == IB_MIG_MIGRATED)
 807                 bth1 |= OPA_BTH_MIG_REQ;
 808         else
 809                 middle = 0;
 810
 811         if (qp->s_flags & RVT_S_ECN) {
 812                 qp->s_flags &= ~RVT_S_ECN;
 813                 /* we recently received a FECN, so return a BECN */
 814                 becn = true;
 815                 middle = 0;
 816         }
 817         if (middle)
 818                 build_ahg(qp, bth2);
 819         else
 820                 qp->s_flags &= ~RVT_S_AHG_VALID;
 821
 822         bth0 |= pkey;
 823         bth0 |= extra_bytes << 20;
 824         hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2);
 825
 826         if (!ppd->lid)
 827                 slid = be32_to_cpu(OPA_LID_PERMISSIVE);
 828         else
 829                 slid = ppd->lid |
 830                         (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
 831                         ((1 << ppd->lmc) - 1));
 832
 833         hfi1_make_16b_hdr(&ps->s_txreq->phdr.hdr.opah,
 834                           slid,
 835                           opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr),
 836                                       16B),
 837                           (qp->s_hdrwords + nwords) >> 1,
 838                           pkey, becn, 0, l4, priv->s_sc);
 839 }
 840
 841 /**
 842  * hfi1_make_ruc_header_9B - build a 9B header
 843  * @qp: the queue pair
 844  * @ohdr: a pointer to the destination header memory
 845  * @bth0: bth0 passed in from the RC/UC builder
 846  * @bth2: bth2 passed in from the RC/UC builder
 847  * @middle: non zero implies indicates ahg "could" be used
 848  * @ps: the current packet state
 849  *
 850  * This routine may disarm ahg under these situations:
 851  * - packet needs a GRH
 852  * - BECN needed
 853  * - migration state not IB_MIG_MIGRATED
 854  */
 855 static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp,
 856                                            struct ib_other_headers *ohdr,
 857                                            u32 bth0, u32 bth2, int middle,
 858                                            struct hfi1_pkt_state *ps)
 859 {
 860         struct hfi1_qp_priv *priv = qp->priv;
 861         struct hfi1_ibport *ibp = ps->ibp;
 862         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
 863         u32 bth1 = 0;
 864         u16 pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
 865         u16 lrh0 = HFI1_LRH_BTH;
 866         u16 slid;
 867         u8 extra_bytes = -ps->s_txreq->s_cur_size & 3;
 868         u32 nwords = SIZE_OF_CRC + ((ps->s_txreq->s_cur_size +
 869                                          extra_bytes) >> 2);
 870
 871         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
 872                 struct ib_grh *grh = &ps->s_txreq->phdr.hdr.ibh.u.l.grh;
 873                 int hdrwords = qp->s_hdrwords - 2;
 874
 875                 lrh0 = HFI1_LRH_GRH;
 876                 qp->s_hdrwords +=
 877                         hfi1_make_grh(ibp, grh,
 878                                       rdma_ah_read_grh(&qp->remote_ah_attr),
 879                                       hdrwords, nwords);
 880                 middle = 0;
 881         }
 882         lrh0 |= (priv->s_sc & 0xf) << 12 |
 883                 (rdma_ah_get_sl(&qp->remote_ah_attr) & 0xf) << 4;
 884
 885         if (qp->s_mig_state == IB_MIG_MIGRATED)
 886                 bth0 |= IB_BTH_MIG_REQ;
 887         else
 888                 middle = 0;
 889
 890         if (qp->s_flags & RVT_S_ECN) {
 891                 qp->s_flags &= ~RVT_S_ECN;
 892                 /* we recently received a FECN, so return a BECN */
 893                 bth1 |= (IB_BECN_MASK << IB_BECN_SHIFT);
 894                 middle = 0;
 895         }
 896         if (middle)
 897                 build_ahg(qp, bth2);
 898         else
 899                 qp->s_flags &= ~RVT_S_AHG_VALID;
 900
 901         bth0 |= pkey;
 902         bth0 |= extra_bytes << 20;
 903         hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2);
 904
 905         if (!ppd->lid)
 906                 slid = be16_to_cpu(IB_LID_PERMISSIVE);
 907         else
 908                 slid = ppd->lid |
 909                         (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
 910                         ((1 << ppd->lmc) - 1));
 911         hfi1_make_ib_hdr(&ps->s_txreq->phdr.hdr.ibh,
 912                          lrh0,
 913                          qp->s_hdrwords + nwords,
 914                          opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr), 9B),
 915                          ppd_from_ibp(ibp)->lid |
 916                                 rdma_ah_get_path_bits(&qp->remote_ah_attr));
 917 }
 918
 919 typedef void (*hfi1_make_ruc_hdr)(struct rvt_qp *qp,
 920                                   struct ib_other_headers *ohdr,
 921                                   u32 bth0, u32 bth2, int middle,
 922                                   struct hfi1_pkt_state *ps);
 923
 924 /* We support only two types - 9B and 16B for now */
 925 static const hfi1_make_ruc_hdr hfi1_ruc_header_tbl[2] = {
 926         [HFI1_PKT_TYPE_9B] = &hfi1_make_ruc_header_9B,
 927         [HFI1_PKT_TYPE_16B] = &hfi1_make_ruc_header_16B
 928 };
 929
 930 void hfi1_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
 931                           u32 bth0, u32 bth2, int middle,
 932                           struct hfi1_pkt_state *ps)
 933 {
 934         struct hfi1_qp_priv *priv = qp->priv;
 935
 936         /*
 937          * reset s_ahg/AHG fields
 938          *
 939          * This insures that the ahgentry/ahgcount
 940          * are at a non-AHG default to protect
 941          * build_verbs_tx_desc() from using
 942          * an include ahgidx.
 943          *
 944          * build_ahg() will modify as appropriate
 945          * to use the AHG feature.
 946          */
 947         priv->s_ahg->tx_flags = 0;
 948         priv->s_ahg->ahgcount = 0;
 949         priv->s_ahg->ahgidx = 0;
 950
 951         /* Make the appropriate header */
 952         hfi1_ruc_header_tbl[priv->hdr_type](qp, ohdr, bth0, bth2, middle, ps);
 953 }
 954
 955 /* when sending, force a reschedule every one of these periods */
 956 #define SEND_RESCHED_TIMEOUT (5 * HZ)  /* 5s in jiffies */
 957
 958 /**
 959  * schedule_send_yield - test for a yield required for QP send engine
 960  * @timeout: Final time for timeout slice for jiffies
 961  * @qp: a pointer to QP
 962  * @ps: a pointer to a structure with commonly lookup values for
 963  *      the the send engine progress
 964  *
 965  * This routine checks if the time slice for the QP has expired
 966  * for RC QPs, if so an additional work entry is queued. At this
 967  * point, other QPs have an opportunity to be scheduled. It
 968  * returns true if a yield is required, otherwise, false
 969  * is returned.
 970  */
 971 static bool schedule_send_yield(struct rvt_qp *qp,
 972                                 struct hfi1_pkt_state *ps)
 973 {
 974         ps->pkts_sent = true;
 975
 976         if (unlikely(time_after(jiffies, ps->timeout))) {
 977                 if (!ps->in_thread ||
 978                     workqueue_congested(ps->cpu, ps->ppd->hfi1_wq)) {
 979                         spin_lock_irqsave(&qp->s_lock, ps->flags);
 980                         qp->s_flags &= ~RVT_S_BUSY;
 981                         hfi1_schedule_send(qp);
 982                         spin_unlock_irqrestore(&qp->s_lock, ps->flags);
 983                         this_cpu_inc(*ps->ppd->dd->send_schedule);
 984                         trace_hfi1_rc_expired_time_slice(qp, true);
 985                         return true;
 986                 }
 987
 988                 cond_resched();
 989                 this_cpu_inc(*ps->ppd->dd->send_schedule);
 990                 ps->timeout = jiffies + ps->timeout_int;
 991         }
 992
 993         trace_hfi1_rc_expired_time_slice(qp, false);
 994         return false;
 995 }
 996
 997 void hfi1_do_send_from_rvt(struct rvt_qp *qp)
 998 {
 999         hfi1_do_send(qp, false);
1000 }
1001
1002 void _hfi1_do_send(struct work_struct *work)
1003 {
1004         struct iowait *wait = container_of(work, struct iowait, iowork);
1005         struct rvt_qp *qp = iowait_to_qp(wait);
1006
1007         hfi1_do_send(qp, true);
1008 }
1009
1010 /**
1011  * hfi1_do_send - perform a send on a QP
1012  * @work: contains a pointer to the QP
1013  * @in_thread: true if in a workqueue thread
1014  *
1015  * Process entries in the send work queue until credit or queue is
1016  * exhausted.  Only allow one CPU to send a packet per QP.
1017  * Otherwise, two threads could send packets out of order.
1018  */
1019 void hfi1_do_send(struct rvt_qp *qp, bool in_thread)
1020 {
1021         struct hfi1_pkt_state ps;
1022         struct hfi1_qp_priv *priv = qp->priv;
1023         int (*make_req)(struct rvt_qp *qp, struct hfi1_pkt_state *ps);
1024
1025         ps.dev = to_idev(qp->ibqp.device);
1026         ps.ibp = to_iport(qp->ibqp.device, qp->port_num);
1027         ps.ppd = ppd_from_ibp(ps.ibp);
1028         ps.in_thread = in_thread;
1029
1030         trace_hfi1_rc_do_send(qp, in_thread);
1031
1032         switch (qp->ibqp.qp_type) {
1033         case IB_QPT_RC:
1034                 if (!loopback && ((rdma_ah_get_dlid(&qp->remote_ah_attr) &
1035                                    ~((1 << ps.ppd->lmc) - 1)) ==
1036                                   ps.ppd->lid)) {
1037                         ruc_loopback(qp);
1038                         return;
1039                 }
1040                 make_req = hfi1_make_rc_req;
1041                 ps.timeout_int = qp->timeout_jiffies;
1042                 break;
1043         case IB_QPT_UC:
1044                 if (!loopback && ((rdma_ah_get_dlid(&qp->remote_ah_attr) &
1045                                    ~((1 << ps.ppd->lmc) - 1)) ==
1046                                   ps.ppd->lid)) {
1047                         ruc_loopback(qp);
1048                         return;
1049                 }
1050                 make_req = hfi1_make_uc_req;
1051                 ps.timeout_int = SEND_RESCHED_TIMEOUT;
1052                 break;
1053         default:
1054                 make_req = hfi1_make_ud_req;
1055                 ps.timeout_int = SEND_RESCHED_TIMEOUT;
1056         }
1057
1058         spin_lock_irqsave(&qp->s_lock, ps.flags);
1059
1060         /* Return if we are already busy processing a work request. */
1061         if (!hfi1_send_ok(qp)) {
1062                 spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1063                 return;
1064         }
1065
1066         qp->s_flags |= RVT_S_BUSY;
1067
1068         ps.timeout_int = ps.timeout_int / 8;
1069         ps.timeout = jiffies + ps.timeout_int;
1070         ps.cpu = priv->s_sde ? priv->s_sde->cpu :
1071                         cpumask_first(cpumask_of_node(ps.ppd->dd->node));
1072         ps.pkts_sent = false;
1073
1074         /* insure a pre-built packet is handled  */
1075         ps.s_txreq = get_waiting_verbs_txreq(qp);
1076         do {
1077                 /* Check for a constructed packet to be sent. */
1078                 if (qp->s_hdrwords != 0) {
1079                         spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1080                         /*
1081                          * If the packet cannot be sent now, return and
1082                          * the send engine will be woken up later.
1083                          */
1084                         if (hfi1_verbs_send(qp, &ps))
1085                                 return;
1086                         /* Record that s_ahg is empty. */
1087                         qp->s_hdrwords = 0;
1088                         /* allow other tasks to run */
1089                         if (schedule_send_yield(qp, &ps))
1090                                 return;
1091
1092                         spin_lock_irqsave(&qp->s_lock, ps.flags);
1093                 }
1094         } while (make_req(qp, &ps));
1095         iowait_starve_clear(ps.pkts_sent, &priv->s_iowait);
1096         spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1097 }
1098
1099 /*
1100  * This should be called with s_lock held.
1101  */
1102 void hfi1_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe,
1103                         enum ib_wc_status status)
1104 {
1105         u32 old_last, last;
1106
1107         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_OR_FLUSH_SEND))
1108                 return;
1109
1110         last = qp->s_last;
1111         old_last = last;
1112         trace_hfi1_qp_send_completion(qp, wqe, last);
1113         if (++last >= qp->s_size)
1114                 last = 0;
1115         trace_hfi1_qp_send_completion(qp, wqe, last);
1116         qp->s_last = last;
1117         /* See post_send() */
1118         barrier();
1119         rvt_put_swqe(wqe);
1120         if (qp->ibqp.qp_type == IB_QPT_UD ||
1121             qp->ibqp.qp_type == IB_QPT_SMI ||
1122             qp->ibqp.qp_type == IB_QPT_GSI)
1123                 atomic_dec(&ibah_to_rvtah(wqe->ud_wr.ah)->refcount);
1124
1125         rvt_qp_swqe_complete(qp,
1126                              wqe,
1127                              ib_hfi1_wc_opcode[wqe->wr.opcode],
1128                              status);
1129
1130         if (qp->s_acked == old_last)
1131                 qp->s_acked = last;
1132         if (qp->s_cur == old_last)
1133                 qp->s_cur = last;
1134         if (qp->s_tail == old_last)
1135                 qp->s_tail = last;
1136         if (qp->state == IB_QPS_SQD && last == qp->s_cur)
1137                 qp->s_draining = 0;
1138 }