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 == READ_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                 break;
 444
 445         case IB_WR_RDMA_WRITE_WITH_IMM:
 446                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
 447                         goto inv_err;
 448                 wc.wc_flags = IB_WC_WITH_IMM;
 449                 wc.ex.imm_data = wqe->wr.ex.imm_data;
 450                 ret = hfi1_rvt_get_rwqe(qp, 1);
 451                 if (ret < 0)
 452                         goto op_err;
 453                 if (!ret)
 454                         goto rnr_nak;
 455                 /* skip copy_last set and qp_access_flags recheck */
 456                 goto do_write;
 457         case IB_WR_RDMA_WRITE:
 458                 copy_last = rvt_is_user_qp(qp);
 459                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
 460                         goto inv_err;
 461 do_write:
 462                 if (wqe->length == 0)
 463                         break;
 464                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
 465                                           wqe->rdma_wr.remote_addr,
 466                                           wqe->rdma_wr.rkey,
 467                                           IB_ACCESS_REMOTE_WRITE)))
 468                         goto acc_err;
 469                 qp->r_sge.sg_list = NULL;
 470                 qp->r_sge.num_sge = 1;
 471                 qp->r_sge.total_len = wqe->length;
 472                 break;
 473
 474         case IB_WR_RDMA_READ:
 475                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
 476                         goto inv_err;
 477                 if (unlikely(!rvt_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
 478                                           wqe->rdma_wr.remote_addr,
 479                                           wqe->rdma_wr.rkey,
 480                                           IB_ACCESS_REMOTE_READ)))
 481                         goto acc_err;
 482                 release = false;
 483                 sqp->s_sge.sg_list = NULL;
 484                 sqp->s_sge.num_sge = 1;
 485                 qp->r_sge.sge = wqe->sg_list[0];
 486                 qp->r_sge.sg_list = wqe->sg_list + 1;
 487                 qp->r_sge.num_sge = wqe->wr.num_sge;
 488                 qp->r_sge.total_len = wqe->length;
 489                 break;
 490
 491         case IB_WR_ATOMIC_CMP_AND_SWP:
 492         case IB_WR_ATOMIC_FETCH_AND_ADD:
 493                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
 494                         goto inv_err;
 495                 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
 496                                           wqe->atomic_wr.remote_addr,
 497                                           wqe->atomic_wr.rkey,
 498                                           IB_ACCESS_REMOTE_ATOMIC)))
 499                         goto acc_err;
 500                 /* Perform atomic OP and save result. */
 501                 maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
 502                 sdata = wqe->atomic_wr.compare_add;
 503                 *(u64 *)sqp->s_sge.sge.vaddr =
 504                         (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
 505                         (u64)atomic64_add_return(sdata, maddr) - sdata :
 506                         (u64)cmpxchg((u64 *)qp->r_sge.sge.vaddr,
 507                                       sdata, wqe->atomic_wr.swap);
 508                 rvt_put_mr(qp->r_sge.sge.mr);
 509                 qp->r_sge.num_sge = 0;
 510                 goto send_comp;
 511
 512         default:
 513                 send_status = IB_WC_LOC_QP_OP_ERR;
 514                 goto serr;
 515         }
 516
 517         sge = &sqp->s_sge.sge;
 518         while (sqp->s_len) {
 519                 u32 len = sqp->s_len;
 520
 521                 if (len > sge->length)
 522                         len = sge->length;
 523                 if (len > sge->sge_length)
 524                         len = sge->sge_length;
 525                 WARN_ON_ONCE(len == 0);
 526                 hfi1_copy_sge(&qp->r_sge, sge->vaddr, len, release, copy_last);
 527                 sge->vaddr += len;
 528                 sge->length -= len;
 529                 sge->sge_length -= len;
 530                 if (sge->sge_length == 0) {
 531                         if (!release)
 532                                 rvt_put_mr(sge->mr);
 533                         if (--sqp->s_sge.num_sge)
 534                                 *sge = *sqp->s_sge.sg_list++;
 535                 } else if (sge->length == 0 && sge->mr->lkey) {
 536                         if (++sge->n >= RVT_SEGSZ) {
 537                                 if (++sge->m >= sge->mr->mapsz)
 538                                         break;
 539                                 sge->n = 0;
 540                         }
 541                         sge->vaddr =
 542                                 sge->mr->map[sge->m]->segs[sge->n].vaddr;
 543                         sge->length =
 544                                 sge->mr->map[sge->m]->segs[sge->n].length;
 545                 }
 546                 sqp->s_len -= len;
 547         }
 548         if (release)
 549                 rvt_put_ss(&qp->r_sge);
 550
 551         if (!test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
 552                 goto send_comp;
 553
 554         if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
 555                 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
 556         else
 557                 wc.opcode = IB_WC_RECV;
 558         wc.wr_id = qp->r_wr_id;
 559         wc.status = IB_WC_SUCCESS;
 560         wc.byte_len = wqe->length;
 561         wc.qp = &qp->ibqp;
 562         wc.src_qp = qp->remote_qpn;
 563         wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
 564         wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
 565         wc.port_num = 1;
 566         /* Signal completion event if the solicited bit is set. */
 567         rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc,
 568                      wqe->wr.send_flags & IB_SEND_SOLICITED);
 569
 570 send_comp:
 571         spin_lock_irqsave(&sqp->s_lock, flags);
 572         ibp->rvp.n_loop_pkts++;
 573 flush_send:
 574         sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
 575         hfi1_send_complete(sqp, wqe, send_status);
 576         if (local_ops) {
 577                 atomic_dec(&sqp->local_ops_pending);
 578                 local_ops = 0;
 579         }
 580         goto again;
 581
 582 rnr_nak:
 583         /* Handle RNR NAK */
 584         if (qp->ibqp.qp_type == IB_QPT_UC)
 585                 goto send_comp;
 586         ibp->rvp.n_rnr_naks++;
 587         /*
 588          * Note: we don't need the s_lock held since the BUSY flag
 589          * makes this single threaded.
 590          */
 591         if (sqp->s_rnr_retry == 0) {
 592                 send_status = IB_WC_RNR_RETRY_EXC_ERR;
 593                 goto serr;
 594         }
 595         if (sqp->s_rnr_retry_cnt < 7)
 596                 sqp->s_rnr_retry--;
 597         spin_lock_irqsave(&sqp->s_lock, flags);
 598         if (!(ib_rvt_state_ops[sqp->state] & RVT_PROCESS_RECV_OK))
 599                 goto clr_busy;
 600         rvt_add_rnr_timer(sqp, qp->r_min_rnr_timer <<
 601                                 IB_AETH_CREDIT_SHIFT);
 602         goto clr_busy;
 603
 604 op_err:
 605         send_status = IB_WC_REM_OP_ERR;
 606         wc.status = IB_WC_LOC_QP_OP_ERR;
 607         goto err;
 608
 609 inv_err:
 610         send_status = IB_WC_REM_INV_REQ_ERR;
 611         wc.status = IB_WC_LOC_QP_OP_ERR;
 612         goto err;
 613
 614 acc_err:
 615         send_status = IB_WC_REM_ACCESS_ERR;
 616         wc.status = IB_WC_LOC_PROT_ERR;
 617 err:
 618         /* responder goes to error state */
 619         rvt_rc_error(qp, wc.status);
 620
 621 serr:
 622         spin_lock_irqsave(&sqp->s_lock, flags);
 623         hfi1_send_complete(sqp, wqe, send_status);
 624         if (sqp->ibqp.qp_type == IB_QPT_RC) {
 625                 int lastwqe = rvt_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
 626
 627                 sqp->s_flags &= ~RVT_S_BUSY;
 628                 spin_unlock_irqrestore(&sqp->s_lock, flags);
 629                 if (lastwqe) {
 630                         struct ib_event ev;
 631
 632                         ev.device = sqp->ibqp.device;
 633                         ev.element.qp = &sqp->ibqp;
 634                         ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 635                         sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
 636                 }
 637                 goto done;
 638         }
 639 clr_busy:
 640         sqp->s_flags &= ~RVT_S_BUSY;
 641 unlock:
 642         spin_unlock_irqrestore(&sqp->s_lock, flags);
 643 done:
 644         rcu_read_unlock();
 645 }
 646
 647 /**
 648  * hfi1_make_grh - construct a GRH header
 649  * @ibp: a pointer to the IB port
 650  * @hdr: a pointer to the GRH header being constructed
 651  * @grh: the global route address to send to
 652  * @hwords: size of header after grh being sent in dwords
 653  * @nwords: the number of 32 bit words of data being sent
 654  *
 655  * Return the size of the header in 32 bit words.
 656  */
 657 u32 hfi1_make_grh(struct hfi1_ibport *ibp, struct ib_grh *hdr,
 658                   const struct ib_global_route *grh, u32 hwords, u32 nwords)
 659 {
 660         hdr->version_tclass_flow =
 661                 cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
 662                             (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
 663                             (grh->flow_label << IB_GRH_FLOW_SHIFT));
 664         hdr->paylen = cpu_to_be16((hwords + nwords) << 2);
 665         /* next_hdr is defined by C8-7 in ch. 8.4.1 */
 666         hdr->next_hdr = IB_GRH_NEXT_HDR;
 667         hdr->hop_limit = grh->hop_limit;
 668         /* The SGID is 32-bit aligned. */
 669         hdr->sgid.global.subnet_prefix = ibp->rvp.gid_prefix;
 670         hdr->sgid.global.interface_id =
 671                 grh->sgid_index < HFI1_GUIDS_PER_PORT ?
 672                 get_sguid(ibp, grh->sgid_index) :
 673                 get_sguid(ibp, HFI1_PORT_GUID_INDEX);
 674         hdr->dgid = grh->dgid;
 675
 676         /* GRH header size in 32-bit words. */
 677         return sizeof(struct ib_grh) / sizeof(u32);
 678 }
 679
 680 #define BTH2_OFFSET (offsetof(struct hfi1_sdma_header, \
 681                               hdr.ibh.u.oth.bth[2]) / 4)
 682
 683 /**
 684  * build_ahg - create ahg in s_ahg
 685  * @qp: a pointer to QP
 686  * @npsn: the next PSN for the request/response
 687  *
 688  * This routine handles the AHG by allocating an ahg entry and causing the
 689  * copy of the first middle.
 690  *
 691  * Subsequent middles use the copied entry, editing the
 692  * PSN with 1 or 2 edits.
 693  */
 694 static inline void build_ahg(struct rvt_qp *qp, u32 npsn)
 695 {
 696         struct hfi1_qp_priv *priv = qp->priv;
 697
 698         if (unlikely(qp->s_flags & RVT_S_AHG_CLEAR))
 699                 clear_ahg(qp);
 700         if (!(qp->s_flags & RVT_S_AHG_VALID)) {
 701                 /* first middle that needs copy  */
 702                 if (qp->s_ahgidx < 0)
 703                         qp->s_ahgidx = sdma_ahg_alloc(priv->s_sde);
 704                 if (qp->s_ahgidx >= 0) {
 705                         qp->s_ahgpsn = npsn;
 706                         priv->s_ahg->tx_flags |= SDMA_TXREQ_F_AHG_COPY;
 707                         /* save to protect a change in another thread */
 708                         priv->s_ahg->ahgidx = qp->s_ahgidx;
 709                         qp->s_flags |= RVT_S_AHG_VALID;
 710                 }
 711         } else {
 712                 /* subsequent middle after valid */
 713                 if (qp->s_ahgidx >= 0) {
 714                         priv->s_ahg->tx_flags |= SDMA_TXREQ_F_USE_AHG;
 715                         priv->s_ahg->ahgidx = qp->s_ahgidx;
 716                         priv->s_ahg->ahgcount++;
 717                         priv->s_ahg->ahgdesc[0] =
 718                                 sdma_build_ahg_descriptor(
 719                                         (__force u16)cpu_to_be16((u16)npsn),
 720                                         BTH2_OFFSET,
 721                                         16,
 722                                         16);
 723                         if ((npsn & 0xffff0000) !=
 724                                         (qp->s_ahgpsn & 0xffff0000)) {
 725                                 priv->s_ahg->ahgcount++;
 726                                 priv->s_ahg->ahgdesc[1] =
 727                                         sdma_build_ahg_descriptor(
 728                                                 (__force u16)cpu_to_be16(
 729                                                         (u16)(npsn >> 16)),
 730                                                 BTH2_OFFSET,
 731                                                 0,
 732                                                 16);
 733                         }
 734                 }
 735         }
 736 }
 737
 738 static inline void hfi1_make_ruc_bth(struct rvt_qp *qp,
 739                                      struct ib_other_headers *ohdr,
 740                                      u32 bth0, u32 bth1, u32 bth2)
 741 {
 742         bth1 |= qp->remote_qpn;
 743         ohdr->bth[0] = cpu_to_be32(bth0);
 744         ohdr->bth[1] = cpu_to_be32(bth1);
 745         ohdr->bth[2] = cpu_to_be32(bth2);
 746 }
 747
 748 static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp,
 749                                             struct ib_other_headers *ohdr,
 750                                             u32 bth0, u32 bth2, int middle,
 751                                             struct hfi1_pkt_state *ps)
 752 {
 753         struct hfi1_qp_priv *priv = qp->priv;
 754         struct hfi1_ibport *ibp = ps->ibp;
 755         struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
 756         u32 bth1 = 0;
 757         u32 slid;
 758         u16 pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
 759         u8 l4 = OPA_16B_L4_IB_LOCAL;
 760         u8 extra_bytes = hfi1_get_16b_padding((qp->s_hdrwords << 2),
 761                                    ps->s_txreq->s_cur_size);
 762         u32 nwords = SIZE_OF_CRC + ((ps->s_txreq->s_cur_size +
 763                                  extra_bytes + SIZE_OF_LT) >> 2);
 764         u8 becn = 0;
 765
 766         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
 767             hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))) {
 768                 struct ib_grh *grh;
 769                 struct ib_global_route *grd =
 770                         rdma_ah_retrieve_grh(&qp->remote_ah_attr);
 771                 int hdrwords;
 772
 773                 /*
 774                  * Ensure OPA GIDs are transformed to IB gids
 775                  * before creating the GRH.
 776                  */
 777                 if (grd->sgid_index == OPA_GID_INDEX)
 778                         grd->sgid_index = 0;
 779                 grh = &ps->s_txreq->phdr.hdr.opah.u.l.grh;
 780                 l4 = OPA_16B_L4_IB_GLOBAL;
 781                 hdrwords = qp->s_hdrwords - 4;
 782                 qp->s_hdrwords += hfi1_make_grh(ibp, grh, grd,
 783                                                 hdrwords, nwords);
 784                 middle = 0;
 785         }
 786
 787         if (qp->s_mig_state == IB_MIG_MIGRATED)
 788                 bth1 |= OPA_BTH_MIG_REQ;
 789         else
 790                 middle = 0;
 791
 792         if (middle)
 793                 build_ahg(qp, bth2);
 794         else
 795                 qp->s_flags &= ~RVT_S_AHG_VALID;
 796
 797         bth0 |= pkey;
 798         bth0 |= extra_bytes << 20;
 799         if (qp->s_flags & RVT_S_ECN) {
 800                 qp->s_flags &= ~RVT_S_ECN;
 801                 /* we recently received a FECN, so return a BECN */
 802                 becn = 1;
 803         }
 804         hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2);
 805
 806         if (!ppd->lid)
 807                 slid = be32_to_cpu(OPA_LID_PERMISSIVE);
 808         else
 809                 slid = ppd->lid |
 810                         (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
 811                         ((1 << ppd->lmc) - 1));
 812
 813         hfi1_make_16b_hdr(&ps->s_txreq->phdr.hdr.opah,
 814                           slid,
 815                           opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr),
 816                                       16B),
 817                           (qp->s_hdrwords + nwords) >> 1,
 818                           pkey, becn, 0, l4, priv->s_sc);
 819 }
 820
 821 static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp,
 822                                            struct ib_other_headers *ohdr,
 823                                            u32 bth0, u32 bth2, int middle,
 824                                            struct hfi1_pkt_state *ps)
 825 {
 826         struct hfi1_qp_priv *priv = qp->priv;
 827         struct hfi1_ibport *ibp = ps->ibp;
 828         u32 bth1 = 0;
 829         u16 pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
 830         u16 lrh0 = HFI1_LRH_BTH;
 831         u8 extra_bytes = -ps->s_txreq->s_cur_size & 3;
 832         u32 nwords = SIZE_OF_CRC + ((ps->s_txreq->s_cur_size +
 833                                          extra_bytes) >> 2);
 834
 835         if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
 836                 struct ib_grh *grh = &ps->s_txreq->phdr.hdr.ibh.u.l.grh;
 837                 int hdrwords = qp->s_hdrwords - 2;
 838
 839                 lrh0 = HFI1_LRH_GRH;
 840                 qp->s_hdrwords +=
 841                         hfi1_make_grh(ibp, grh,
 842                                       rdma_ah_read_grh(&qp->remote_ah_attr),
 843                                       hdrwords, nwords);
 844                 middle = 0;
 845         }
 846         lrh0 |= (priv->s_sc & 0xf) << 12 |
 847                 (rdma_ah_get_sl(&qp->remote_ah_attr) & 0xf) << 4;
 848
 849         if (qp->s_mig_state == IB_MIG_MIGRATED)
 850                 bth0 |= IB_BTH_MIG_REQ;
 851         else
 852                 middle = 0;
 853
 854         if (middle)
 855                 build_ahg(qp, bth2);
 856         else
 857                 qp->s_flags &= ~RVT_S_AHG_VALID;
 858
 859         bth0 |= pkey;
 860         bth0 |= extra_bytes << 20;
 861         if (qp->s_flags & RVT_S_ECN) {
 862                 qp->s_flags &= ~RVT_S_ECN;
 863                 /* we recently received a FECN, so return a BECN */
 864                 bth1 |= (IB_BECN_MASK << IB_BECN_SHIFT);
 865         }
 866         hfi1_make_ruc_bth(qp, ohdr, bth0, bth1, bth2);
 867         hfi1_make_ib_hdr(&ps->s_txreq->phdr.hdr.ibh,
 868                          lrh0,
 869                          qp->s_hdrwords + nwords,
 870                          opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr), 9B),
 871                          ppd_from_ibp(ibp)->lid |
 872                                 rdma_ah_get_path_bits(&qp->remote_ah_attr));
 873 }
 874
 875 typedef void (*hfi1_make_ruc_hdr)(struct rvt_qp *qp,
 876                                   struct ib_other_headers *ohdr,
 877                                   u32 bth0, u32 bth2, int middle,
 878                                   struct hfi1_pkt_state *ps);
 879
 880 /* We support only two types - 9B and 16B for now */
 881 static const hfi1_make_ruc_hdr hfi1_ruc_header_tbl[2] = {
 882         [HFI1_PKT_TYPE_9B] = &hfi1_make_ruc_header_9B,
 883         [HFI1_PKT_TYPE_16B] = &hfi1_make_ruc_header_16B
 884 };
 885
 886 void hfi1_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
 887                           u32 bth0, u32 bth2, int middle,
 888                           struct hfi1_pkt_state *ps)
 889 {
 890         struct hfi1_qp_priv *priv = qp->priv;
 891
 892         /*
 893          * reset s_ahg/AHG fields
 894          *
 895          * This insures that the ahgentry/ahgcount
 896          * are at a non-AHG default to protect
 897          * build_verbs_tx_desc() from using
 898          * an include ahgidx.
 899          *
 900          * build_ahg() will modify as appropriate
 901          * to use the AHG feature.
 902          */
 903         priv->s_ahg->tx_flags = 0;
 904         priv->s_ahg->ahgcount = 0;
 905         priv->s_ahg->ahgidx = 0;
 906
 907         /* Make the appropriate header */
 908         hfi1_ruc_header_tbl[priv->hdr_type](qp, ohdr, bth0, bth2, middle, ps);
 909 }
 910
 911 /* when sending, force a reschedule every one of these periods */
 912 #define SEND_RESCHED_TIMEOUT (5 * HZ)  /* 5s in jiffies */
 913
 914 /**
 915  * schedule_send_yield - test for a yield required for QP send engine
 916  * @timeout: Final time for timeout slice for jiffies
 917  * @qp: a pointer to QP
 918  * @ps: a pointer to a structure with commonly lookup values for
 919  *      the the send engine progress
 920  *
 921  * This routine checks if the time slice for the QP has expired
 922  * for RC QPs, if so an additional work entry is queued. At this
 923  * point, other QPs have an opportunity to be scheduled. It
 924  * returns true if a yield is required, otherwise, false
 925  * is returned.
 926  */
 927 static bool schedule_send_yield(struct rvt_qp *qp,
 928                                 struct hfi1_pkt_state *ps)
 929 {
 930         ps->pkts_sent = true;
 931
 932         if (unlikely(time_after(jiffies, ps->timeout))) {
 933                 if (!ps->in_thread ||
 934                     workqueue_congested(ps->cpu, ps->ppd->hfi1_wq)) {
 935                         spin_lock_irqsave(&qp->s_lock, ps->flags);
 936                         qp->s_flags &= ~RVT_S_BUSY;
 937                         hfi1_schedule_send(qp);
 938                         spin_unlock_irqrestore(&qp->s_lock, ps->flags);
 939                         this_cpu_inc(*ps->ppd->dd->send_schedule);
 940                         trace_hfi1_rc_expired_time_slice(qp, true);
 941                         return true;
 942                 }
 943
 944                 cond_resched();
 945                 this_cpu_inc(*ps->ppd->dd->send_schedule);
 946                 ps->timeout = jiffies + ps->timeout_int;
 947         }
 948
 949         trace_hfi1_rc_expired_time_slice(qp, false);
 950         return false;
 951 }
 952
 953 void hfi1_do_send_from_rvt(struct rvt_qp *qp)
 954 {
 955         hfi1_do_send(qp, false);
 956 }
 957
 958 void _hfi1_do_send(struct work_struct *work)
 959 {
 960         struct iowait *wait = container_of(work, struct iowait, iowork);
 961         struct rvt_qp *qp = iowait_to_qp(wait);
 962
 963         hfi1_do_send(qp, true);
 964 }
 965
 966 /**
 967  * hfi1_do_send - perform a send on a QP
 968  * @work: contains a pointer to the QP
 969  * @in_thread: true if in a workqueue thread
 970  *
 971  * Process entries in the send work queue until credit or queue is
 972  * exhausted.  Only allow one CPU to send a packet per QP.
 973  * Otherwise, two threads could send packets out of order.
 974  */
 975 void hfi1_do_send(struct rvt_qp *qp, bool in_thread)
 976 {
 977         struct hfi1_pkt_state ps;
 978         struct hfi1_qp_priv *priv = qp->priv;
 979         int (*make_req)(struct rvt_qp *qp, struct hfi1_pkt_state *ps);
 980
 981         ps.dev = to_idev(qp->ibqp.device);
 982         ps.ibp = to_iport(qp->ibqp.device, qp->port_num);
 983         ps.ppd = ppd_from_ibp(ps.ibp);
 984         ps.in_thread = in_thread;
 985
 986         trace_hfi1_rc_do_send(qp, in_thread);
 987
 988         switch (qp->ibqp.qp_type) {
 989         case IB_QPT_RC:
 990                 if (!loopback && ((rdma_ah_get_dlid(&qp->remote_ah_attr) &
 991                                    ~((1 << ps.ppd->lmc) - 1)) ==
 992                                   ps.ppd->lid)) {
 993                         ruc_loopback(qp);
 994                         return;
 995                 }
 996                 make_req = hfi1_make_rc_req;
 997                 ps.timeout_int = qp->timeout_jiffies;
 998                 break;
 999         case IB_QPT_UC:
1000                 if (!loopback && ((rdma_ah_get_dlid(&qp->remote_ah_attr) &
1001                                    ~((1 << ps.ppd->lmc) - 1)) ==
1002                                   ps.ppd->lid)) {
1003                         ruc_loopback(qp);
1004                         return;
1005                 }
1006                 make_req = hfi1_make_uc_req;
1007                 ps.timeout_int = SEND_RESCHED_TIMEOUT;
1008                 break;
1009         default:
1010                 make_req = hfi1_make_ud_req;
1011                 ps.timeout_int = SEND_RESCHED_TIMEOUT;
1012         }
1013
1014         spin_lock_irqsave(&qp->s_lock, ps.flags);
1015
1016         /* Return if we are already busy processing a work request. */
1017         if (!hfi1_send_ok(qp)) {
1018                 spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1019                 return;
1020         }
1021
1022         qp->s_flags |= RVT_S_BUSY;
1023
1024         ps.timeout_int = ps.timeout_int / 8;
1025         ps.timeout = jiffies + ps.timeout_int;
1026         ps.cpu = priv->s_sde ? priv->s_sde->cpu :
1027                         cpumask_first(cpumask_of_node(ps.ppd->dd->node));
1028         ps.pkts_sent = false;
1029
1030         /* insure a pre-built packet is handled  */
1031         ps.s_txreq = get_waiting_verbs_txreq(qp);
1032         do {
1033                 /* Check for a constructed packet to be sent. */
1034                 if (qp->s_hdrwords != 0) {
1035                         spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1036                         /*
1037                          * If the packet cannot be sent now, return and
1038                          * the send engine will be woken up later.
1039                          */
1040                         if (hfi1_verbs_send(qp, &ps))
1041                                 return;
1042                         /* Record that s_ahg is empty. */
1043                         qp->s_hdrwords = 0;
1044                         /* allow other tasks to run */
1045                         if (schedule_send_yield(qp, &ps))
1046                                 return;
1047
1048                         spin_lock_irqsave(&qp->s_lock, ps.flags);
1049                 }
1050         } while (make_req(qp, &ps));
1051         iowait_starve_clear(ps.pkts_sent, &priv->s_iowait);
1052         spin_unlock_irqrestore(&qp->s_lock, ps.flags);
1053 }
1054
1055 /*
1056  * This should be called with s_lock held.
1057  */
1058 void hfi1_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe,
1059                         enum ib_wc_status status)
1060 {
1061         u32 old_last, last;
1062
1063         if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_OR_FLUSH_SEND))
1064                 return;
1065
1066         last = qp->s_last;
1067         old_last = last;
1068         trace_hfi1_qp_send_completion(qp, wqe, last);
1069         if (++last >= qp->s_size)
1070                 last = 0;
1071         trace_hfi1_qp_send_completion(qp, wqe, last);
1072         qp->s_last = last;
1073         /* See post_send() */
1074         barrier();
1075         rvt_put_swqe(wqe);
1076         if (qp->ibqp.qp_type == IB_QPT_UD ||
1077             qp->ibqp.qp_type == IB_QPT_SMI ||
1078             qp->ibqp.qp_type == IB_QPT_GSI)
1079                 atomic_dec(&ibah_to_rvtah(wqe->ud_wr.ah)->refcount);
1080
1081         rvt_qp_swqe_complete(qp,
1082                              wqe,
1083                              ib_hfi1_wc_opcode[wqe->wr.opcode],
1084                              status);
1085
1086         if (qp->s_acked == old_last)
1087                 qp->s_acked = last;
1088         if (qp->s_cur == old_last)
1089                 qp->s_cur = last;
1090         if (qp->s_tail == old_last)
1091                 qp->s_tail = last;
1092         if (qp->state == IB_QPS_SQD && last == qp->s_cur)
1093                 qp->s_draining = 0;
1094 }