kernel/drivers/infiniband/hw/qib/qib_ruc.c

   1 /*
   2  * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
   3  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/spinlock.h>
  35 #include <rdma/ib_smi.h>
  36
  37 #include "qib.h"
  38 #include "qib_mad.h"
  39
  40 /*
  41  * Convert the AETH RNR timeout code into the number of microseconds.
  42  */
  43 const u32 ib_qib_rnr_table[32] = {
  44         655360, /* 00: 655.36 */
  45         10,     /* 01:    .01 */
  46         20,     /* 02     .02 */
  47         30,     /* 03:    .03 */
  48         40,     /* 04:    .04 */
  49         60,     /* 05:    .06 */
  50         80,     /* 06:    .08 */
  51         120,    /* 07:    .12 */
  52         160,    /* 08:    .16 */
  53         240,    /* 09:    .24 */
  54         320,    /* 0A:    .32 */
  55         480,    /* 0B:    .48 */
  56         640,    /* 0C:    .64 */
  57         960,    /* 0D:    .96 */
  58         1280,   /* 0E:   1.28 */
  59         1920,   /* 0F:   1.92 */
  60         2560,   /* 10:   2.56 */
  61         3840,   /* 11:   3.84 */
  62         5120,   /* 12:   5.12 */
  63         7680,   /* 13:   7.68 */
  64         10240,  /* 14:  10.24 */
  65         15360,  /* 15:  15.36 */
  66         20480,  /* 16:  20.48 */
  67         30720,  /* 17:  30.72 */
  68         40960,  /* 18:  40.96 */
  69         61440,  /* 19:  61.44 */
  70         81920,  /* 1A:  81.92 */
  71         122880, /* 1B: 122.88 */
  72         163840, /* 1C: 163.84 */
  73         245760, /* 1D: 245.76 */
  74         327680, /* 1E: 327.68 */
  75         491520  /* 1F: 491.52 */
  76 };
  77
  78 /*
  79  * Validate a RWQE and fill in the SGE state.
  80  * Return 1 if OK.
  81  */
  82 static int qib_init_sge(struct qib_qp *qp, struct qib_rwqe *wqe)
  83 {
  84         int i, j, ret;
  85         struct ib_wc wc;
  86         struct qib_lkey_table *rkt;
  87         struct qib_pd *pd;
  88         struct qib_sge_state *ss;
  89
  90         rkt = &to_idev(qp->ibqp.device)->lk_table;
  91         pd = to_ipd(qp->ibqp.srq ? qp->ibqp.srq->pd : qp->ibqp.pd);
  92         ss = &qp->r_sge;
  93         ss->sg_list = qp->r_sg_list;
  94         qp->r_len = 0;
  95         for (i = j = 0; i < wqe->num_sge; i++) {
  96                 if (wqe->sg_list[i].length == 0)
  97                         continue;
  98                 /* Check LKEY */
  99                 if (!qib_lkey_ok(rkt, pd, j ? &ss->sg_list[j - 1] : &ss->sge,
 100                                  &wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
 101                         goto bad_lkey;
 102                 qp->r_len += wqe->sg_list[i].length;
 103                 j++;
 104         }
 105         ss->num_sge = j;
 106         ss->total_len = qp->r_len;
 107         ret = 1;
 108         goto bail;
 109
 110 bad_lkey:
 111         while (j) {
 112                 struct qib_sge *sge = --j ? &ss->sg_list[j - 1] : &ss->sge;
 113
 114                 qib_put_mr(sge->mr);
 115         }
 116         ss->num_sge = 0;
 117         memset(&wc, 0, sizeof(wc));
 118         wc.wr_id = wqe->wr_id;
 119         wc.status = IB_WC_LOC_PROT_ERR;
 120         wc.opcode = IB_WC_RECV;
 121         wc.qp = &qp->ibqp;
 122         /* Signal solicited completion event. */
 123         qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 124         ret = 0;
 125 bail:
 126         return ret;
 127 }
 128
 129 /**
 130  * qib_get_rwqe - copy the next RWQE into the QP's RWQE
 131  * @qp: the QP
 132  * @wr_id_only: update qp->r_wr_id only, not qp->r_sge
 133  *
 134  * Return -1 if there is a local error, 0 if no RWQE is available,
 135  * otherwise return 1.
 136  *
 137  * Can be called from interrupt level.
 138  */
 139 int qib_get_rwqe(struct qib_qp *qp, int wr_id_only)
 140 {
 141         unsigned long flags;
 142         struct qib_rq *rq;
 143         struct qib_rwq *wq;
 144         struct qib_srq *srq;
 145         struct qib_rwqe *wqe;
 146         void (*handler)(struct ib_event *, void *);
 147         u32 tail;
 148         int ret;
 149
 150         if (qp->ibqp.srq) {
 151                 srq = to_isrq(qp->ibqp.srq);
 152                 handler = srq->ibsrq.event_handler;
 153                 rq = &srq->rq;
 154         } else {
 155                 srq = NULL;
 156                 handler = NULL;
 157                 rq = &qp->r_rq;
 158         }
 159
 160         spin_lock_irqsave(&rq->lock, flags);
 161         if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK)) {
 162                 ret = 0;
 163                 goto unlock;
 164         }
 165
 166         wq = rq->wq;
 167         tail = wq->tail;
 168         /* Validate tail before using it since it is user writable. */
 169         if (tail >= rq->size)
 170                 tail = 0;
 171         if (unlikely(tail == wq->head)) {
 172                 ret = 0;
 173                 goto unlock;
 174         }
 175         /* Make sure entry is read after head index is read. */
 176         smp_rmb();
 177         wqe = get_rwqe_ptr(rq, tail);
 178         /*
 179          * Even though we update the tail index in memory, the verbs
 180          * consumer is not supposed to post more entries until a
 181          * completion is generated.
 182          */
 183         if (++tail >= rq->size)
 184                 tail = 0;
 185         wq->tail = tail;
 186         if (!wr_id_only && !qib_init_sge(qp, wqe)) {
 187                 ret = -1;
 188                 goto unlock;
 189         }
 190         qp->r_wr_id = wqe->wr_id;
 191
 192         ret = 1;
 193         set_bit(QIB_R_WRID_VALID, &qp->r_aflags);
 194         if (handler) {
 195                 u32 n;
 196
 197                 /*
 198                  * Validate head pointer value and compute
 199                  * the number of remaining WQEs.
 200                  */
 201                 n = wq->head;
 202                 if (n >= rq->size)
 203                         n = 0;
 204                 if (n < tail)
 205                         n += rq->size - tail;
 206                 else
 207                         n -= tail;
 208                 if (n < srq->limit) {
 209                         struct ib_event ev;
 210
 211                         srq->limit = 0;
 212                         spin_unlock_irqrestore(&rq->lock, flags);
 213                         ev.device = qp->ibqp.device;
 214                         ev.element.srq = qp->ibqp.srq;
 215                         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
 216                         handler(&ev, srq->ibsrq.srq_context);
 217                         goto bail;
 218                 }
 219         }
 220 unlock:
 221         spin_unlock_irqrestore(&rq->lock, flags);
 222 bail:
 223         return ret;
 224 }
 225
 226 /*
 227  * Switch to alternate path.
 228  * The QP s_lock should be held and interrupts disabled.
 229  */
 230 void qib_migrate_qp(struct qib_qp *qp)
 231 {
 232         struct ib_event ev;
 233
 234         qp->s_mig_state = IB_MIG_MIGRATED;
 235         qp->remote_ah_attr = qp->alt_ah_attr;
 236         qp->port_num = qp->alt_ah_attr.port_num;
 237         qp->s_pkey_index = qp->s_alt_pkey_index;
 238
 239         ev.device = qp->ibqp.device;
 240         ev.element.qp = &qp->ibqp;
 241         ev.event = IB_EVENT_PATH_MIG;
 242         qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 243 }
 244
 245 static __be64 get_sguid(struct qib_ibport *ibp, unsigned index)
 246 {
 247         if (!index) {
 248                 struct qib_pportdata *ppd = ppd_from_ibp(ibp);
 249
 250                 return ppd->guid;
 251         }
 252         return ibp->guids[index - 1];
 253 }
 254
 255 static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
 256 {
 257         return (gid->global.interface_id == id &&
 258                 (gid->global.subnet_prefix == gid_prefix ||
 259                  gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
 260 }
 261
 262 /*
 263  *
 264  * This should be called with the QP r_lock held.
 265  *
 266  * The s_lock will be acquired around the qib_migrate_qp() call.
 267  */
 268 int qib_ruc_check_hdr(struct qib_ibport *ibp, struct qib_ib_header *hdr,
 269                       int has_grh, struct qib_qp *qp, u32 bth0)
 270 {
 271         __be64 guid;
 272         unsigned long flags;
 273
 274         if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
 275                 if (!has_grh) {
 276                         if (qp->alt_ah_attr.ah_flags & IB_AH_GRH)
 277                                 goto err;
 278                 } else {
 279                         if (!(qp->alt_ah_attr.ah_flags & IB_AH_GRH))
 280                                 goto err;
 281                         guid = get_sguid(ibp, qp->alt_ah_attr.grh.sgid_index);
 282                         if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
 283                                 goto err;
 284                         if (!gid_ok(&hdr->u.l.grh.sgid,
 285                             qp->alt_ah_attr.grh.dgid.global.subnet_prefix,
 286                             qp->alt_ah_attr.grh.dgid.global.interface_id))
 287                                 goto err;
 288                 }
 289                 if (!qib_pkey_ok((u16)bth0,
 290                                  qib_get_pkey(ibp, qp->s_alt_pkey_index))) {
 291                         qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
 292                                       (u16)bth0,
 293                                       (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
 294                                       0, qp->ibqp.qp_num,
 295                                       hdr->lrh[3], hdr->lrh[1]);
 296                         goto err;
 297                 }
 298                 /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
 299                 if (be16_to_cpu(hdr->lrh[3]) != qp->alt_ah_attr.dlid ||
 300                     ppd_from_ibp(ibp)->port != qp->alt_ah_attr.port_num)
 301                         goto err;
 302                 spin_lock_irqsave(&qp->s_lock, flags);
 303                 qib_migrate_qp(qp);
 304                 spin_unlock_irqrestore(&qp->s_lock, flags);
 305         } else {
 306                 if (!has_grh) {
 307                         if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
 308                                 goto err;
 309                 } else {
 310                         if (!(qp->remote_ah_attr.ah_flags & IB_AH_GRH))
 311                                 goto err;
 312                         guid = get_sguid(ibp,
 313                                          qp->remote_ah_attr.grh.sgid_index);
 314                         if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
 315                                 goto err;
 316                         if (!gid_ok(&hdr->u.l.grh.sgid,
 317                             qp->remote_ah_attr.grh.dgid.global.subnet_prefix,
 318                             qp->remote_ah_attr.grh.dgid.global.interface_id))
 319                                 goto err;
 320                 }
 321                 if (!qib_pkey_ok((u16)bth0,
 322                                  qib_get_pkey(ibp, qp->s_pkey_index))) {
 323                         qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
 324                                       (u16)bth0,
 325                                       (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
 326                                       0, qp->ibqp.qp_num,
 327                                       hdr->lrh[3], hdr->lrh[1]);
 328                         goto err;
 329                 }
 330                 /* Validate the SLID. See Ch. 9.6.1.5 */
 331                 if (be16_to_cpu(hdr->lrh[3]) != qp->remote_ah_attr.dlid ||
 332                     ppd_from_ibp(ibp)->port != qp->port_num)
 333                         goto err;
 334                 if (qp->s_mig_state == IB_MIG_REARM &&
 335                     !(bth0 & IB_BTH_MIG_REQ))
 336                         qp->s_mig_state = IB_MIG_ARMED;
 337         }
 338
 339         return 0;
 340
 341 err:
 342         return 1;
 343 }
 344
 345 /**
 346  * qib_ruc_loopback - handle UC and RC lookback requests
 347  * @sqp: the sending QP
 348  *
 349  * This is called from qib_do_send() to
 350  * forward a WQE addressed to the same HCA.
 351  * Note that although we are single threaded due to the tasklet, we still
 352  * have to protect against post_send().  We don't have to worry about
 353  * receive interrupts since this is a connected protocol and all packets
 354  * will pass through here.
 355  */
 356 static void qib_ruc_loopback(struct qib_qp *sqp)
 357 {
 358         struct qib_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
 359         struct qib_qp *qp;
 360         struct qib_swqe *wqe;
 361         struct qib_sge *sge;
 362         unsigned long flags;
 363         struct ib_wc wc;
 364         u64 sdata;
 365         atomic64_t *maddr;
 366         enum ib_wc_status send_status;
 367         int release;
 368         int ret;
 369
 370         /*
 371          * Note that we check the responder QP state after
 372          * checking the requester's state.
 373          */
 374         qp = qib_lookup_qpn(ibp, sqp->remote_qpn);
 375
 376         spin_lock_irqsave(&sqp->s_lock, flags);
 377
 378         /* Return if we are already busy processing a work request. */
 379         if ((sqp->s_flags & (QIB_S_BUSY | QIB_S_ANY_WAIT)) ||
 380             !(ib_qib_state_ops[sqp->state] & QIB_PROCESS_OR_FLUSH_SEND))
 381                 goto unlock;
 382
 383         sqp->s_flags |= QIB_S_BUSY;
 384
 385 again:
 386         if (sqp->s_last == sqp->s_head)
 387                 goto clr_busy;
 388         wqe = get_swqe_ptr(sqp, sqp->s_last);
 389
 390         /* Return if it is not OK to start a new work reqeust. */
 391         if (!(ib_qib_state_ops[sqp->state] & QIB_PROCESS_NEXT_SEND_OK)) {
 392                 if (!(ib_qib_state_ops[sqp->state] & QIB_FLUSH_SEND))
 393                         goto clr_busy;
 394                 /* We are in the error state, flush the work request. */
 395                 send_status = IB_WC_WR_FLUSH_ERR;
 396                 goto flush_send;
 397         }
 398
 399         /*
 400          * We can rely on the entry not changing without the s_lock
 401          * being held until we update s_last.
 402          * We increment s_cur to indicate s_last is in progress.
 403          */
 404         if (sqp->s_last == sqp->s_cur) {
 405                 if (++sqp->s_cur >= sqp->s_size)
 406                         sqp->s_cur = 0;
 407         }
 408         spin_unlock_irqrestore(&sqp->s_lock, flags);
 409
 410         if (!qp || !(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK) ||
 411             qp->ibqp.qp_type != sqp->ibqp.qp_type) {
 412                 ibp->n_pkt_drops++;
 413                 /*
 414                  * For RC, the requester would timeout and retry so
 415                  * shortcut the timeouts and just signal too many retries.
 416                  */
 417                 if (sqp->ibqp.qp_type == IB_QPT_RC)
 418                         send_status = IB_WC_RETRY_EXC_ERR;
 419                 else
 420                         send_status = IB_WC_SUCCESS;
 421                 goto serr;
 422         }
 423
 424         memset(&wc, 0, sizeof(wc));
 425         send_status = IB_WC_SUCCESS;
 426
 427         release = 1;
 428         sqp->s_sge.sge = wqe->sg_list[0];
 429         sqp->s_sge.sg_list = wqe->sg_list + 1;
 430         sqp->s_sge.num_sge = wqe->wr.num_sge;
 431         sqp->s_len = wqe->length;
 432         switch (wqe->wr.opcode) {
 433         case IB_WR_SEND_WITH_IMM:
 434                 wc.wc_flags = IB_WC_WITH_IMM;
 435                 wc.ex.imm_data = wqe->wr.ex.imm_data;
 436                 /* FALLTHROUGH */
 437         case IB_WR_SEND:
 438                 ret = qib_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 = qib_get_rwqe(qp, 1);
 451                 if (ret < 0)
 452                         goto op_err;
 453                 if (!ret)
 454                         goto rnr_nak;
 455                 /* FALLTHROUGH */
 456         case IB_WR_RDMA_WRITE:
 457                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
 458                         goto inv_err;
 459                 if (wqe->length == 0)
 460                         break;
 461                 if (unlikely(!qib_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
 462                                           wqe->rdma_wr.remote_addr,
 463                                           wqe->rdma_wr.rkey,
 464                                           IB_ACCESS_REMOTE_WRITE)))
 465                         goto acc_err;
 466                 qp->r_sge.sg_list = NULL;
 467                 qp->r_sge.num_sge = 1;
 468                 qp->r_sge.total_len = wqe->length;
 469                 break;
 470
 471         case IB_WR_RDMA_READ:
 472                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
 473                         goto inv_err;
 474                 if (unlikely(!qib_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
 475                                           wqe->rdma_wr.remote_addr,
 476                                           wqe->rdma_wr.rkey,
 477                                           IB_ACCESS_REMOTE_READ)))
 478                         goto acc_err;
 479                 release = 0;
 480                 sqp->s_sge.sg_list = NULL;
 481                 sqp->s_sge.num_sge = 1;
 482                 qp->r_sge.sge = wqe->sg_list[0];
 483                 qp->r_sge.sg_list = wqe->sg_list + 1;
 484                 qp->r_sge.num_sge = wqe->wr.num_sge;
 485                 qp->r_sge.total_len = wqe->length;
 486                 break;
 487
 488         case IB_WR_ATOMIC_CMP_AND_SWP:
 489         case IB_WR_ATOMIC_FETCH_AND_ADD:
 490                 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
 491                         goto inv_err;
 492                 if (unlikely(!qib_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
 493                                           wqe->atomic_wr.remote_addr,
 494                                           wqe->atomic_wr.rkey,
 495                                           IB_ACCESS_REMOTE_ATOMIC)))
 496                         goto acc_err;
 497                 /* Perform atomic OP and save result. */
 498                 maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
 499                 sdata = wqe->atomic_wr.compare_add;
 500                 *(u64 *) sqp->s_sge.sge.vaddr =
 501                         (wqe->atomic_wr.wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
 502                         (u64) atomic64_add_return(sdata, maddr) - sdata :
 503                         (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
 504                                       sdata, wqe->atomic_wr.swap);
 505                 qib_put_mr(qp->r_sge.sge.mr);
 506                 qp->r_sge.num_sge = 0;
 507                 goto send_comp;
 508
 509         default:
 510                 send_status = IB_WC_LOC_QP_OP_ERR;
 511                 goto serr;
 512         }
 513
 514         sge = &sqp->s_sge.sge;
 515         while (sqp->s_len) {
 516                 u32 len = sqp->s_len;
 517
 518                 if (len > sge->length)
 519                         len = sge->length;
 520                 if (len > sge->sge_length)
 521                         len = sge->sge_length;
 522                 BUG_ON(len == 0);
 523                 qib_copy_sge(&qp->r_sge, sge->vaddr, len, release);
 524                 sge->vaddr += len;
 525                 sge->length -= len;
 526                 sge->sge_length -= len;
 527                 if (sge->sge_length == 0) {
 528                         if (!release)
 529                                 qib_put_mr(sge->mr);
 530                         if (--sqp->s_sge.num_sge)
 531                                 *sge = *sqp->s_sge.sg_list++;
 532                 } else if (sge->length == 0 && sge->mr->lkey) {
 533                         if (++sge->n >= QIB_SEGSZ) {
 534                                 if (++sge->m >= sge->mr->mapsz)
 535                                         break;
 536                                 sge->n = 0;
 537                         }
 538                         sge->vaddr =
 539                                 sge->mr->map[sge->m]->segs[sge->n].vaddr;
 540                         sge->length =
 541                                 sge->mr->map[sge->m]->segs[sge->n].length;
 542                 }
 543                 sqp->s_len -= len;
 544         }
 545         if (release)
 546                 qib_put_ss(&qp->r_sge);
 547
 548         if (!test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags))
 549                 goto send_comp;
 550
 551         if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
 552                 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
 553         else
 554                 wc.opcode = IB_WC_RECV;
 555         wc.wr_id = qp->r_wr_id;
 556         wc.status = IB_WC_SUCCESS;
 557         wc.byte_len = wqe->length;
 558         wc.qp = &qp->ibqp;
 559         wc.src_qp = qp->remote_qpn;
 560         wc.slid = qp->remote_ah_attr.dlid;
 561         wc.sl = qp->remote_ah_attr.sl;
 562         wc.port_num = 1;
 563         /* Signal completion event if the solicited bit is set. */
 564         qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
 565                        wqe->wr.send_flags & IB_SEND_SOLICITED);
 566
 567 send_comp:
 568         spin_lock_irqsave(&sqp->s_lock, flags);
 569         ibp->n_loop_pkts++;
 570 flush_send:
 571         sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
 572         qib_send_complete(sqp, wqe, send_status);
 573         goto again;
 574
 575 rnr_nak:
 576         /* Handle RNR NAK */
 577         if (qp->ibqp.qp_type == IB_QPT_UC)
 578                 goto send_comp;
 579         ibp->n_rnr_naks++;
 580         /*
 581          * Note: we don't need the s_lock held since the BUSY flag
 582          * makes this single threaded.
 583          */
 584         if (sqp->s_rnr_retry == 0) {
 585                 send_status = IB_WC_RNR_RETRY_EXC_ERR;
 586                 goto serr;
 587         }
 588         if (sqp->s_rnr_retry_cnt < 7)
 589                 sqp->s_rnr_retry--;
 590         spin_lock_irqsave(&sqp->s_lock, flags);
 591         if (!(ib_qib_state_ops[sqp->state] & QIB_PROCESS_RECV_OK))
 592                 goto clr_busy;
 593         sqp->s_flags |= QIB_S_WAIT_RNR;
 594         sqp->s_timer.function = qib_rc_rnr_retry;
 595         sqp->s_timer.expires = jiffies +
 596                 usecs_to_jiffies(ib_qib_rnr_table[qp->r_min_rnr_timer]);
 597         add_timer(&sqp->s_timer);
 598         goto clr_busy;
 599
 600 op_err:
 601         send_status = IB_WC_REM_OP_ERR;
 602         wc.status = IB_WC_LOC_QP_OP_ERR;
 603         goto err;
 604
 605 inv_err:
 606         send_status = IB_WC_REM_INV_REQ_ERR;
 607         wc.status = IB_WC_LOC_QP_OP_ERR;
 608         goto err;
 609
 610 acc_err:
 611         send_status = IB_WC_REM_ACCESS_ERR;
 612         wc.status = IB_WC_LOC_PROT_ERR;
 613 err:
 614         /* responder goes to error state */
 615         qib_rc_error(qp, wc.status);
 616
 617 serr:
 618         spin_lock_irqsave(&sqp->s_lock, flags);
 619         qib_send_complete(sqp, wqe, send_status);
 620         if (sqp->ibqp.qp_type == IB_QPT_RC) {
 621                 int lastwqe = qib_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
 622
 623                 sqp->s_flags &= ~QIB_S_BUSY;
 624                 spin_unlock_irqrestore(&sqp->s_lock, flags);
 625                 if (lastwqe) {
 626                         struct ib_event ev;
 627
 628                         ev.device = sqp->ibqp.device;
 629                         ev.element.qp = &sqp->ibqp;
 630                         ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 631                         sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
 632                 }
 633                 goto done;
 634         }
 635 clr_busy:
 636         sqp->s_flags &= ~QIB_S_BUSY;
 637 unlock:
 638         spin_unlock_irqrestore(&sqp->s_lock, flags);
 639 done:
 640         if (qp && atomic_dec_and_test(&qp->refcount))
 641                 wake_up(&qp->wait);
 642 }
 643
 644 /**
 645  * qib_make_grh - construct a GRH header
 646  * @ibp: a pointer to the IB port
 647  * @hdr: a pointer to the GRH header being constructed
 648  * @grh: the global route address to send to
 649  * @hwords: the number of 32 bit words of header being sent
 650  * @nwords: the number of 32 bit words of data being sent
 651  *
 652  * Return the size of the header in 32 bit words.
 653  */
 654 u32 qib_make_grh(struct qib_ibport *ibp, struct ib_grh *hdr,
 655                  struct ib_global_route *grh, u32 hwords, u32 nwords)
 656 {
 657         hdr->version_tclass_flow =
 658                 cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
 659                             (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
 660                             (grh->flow_label << IB_GRH_FLOW_SHIFT));
 661         hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
 662         /* next_hdr is defined by C8-7 in ch. 8.4.1 */
 663         hdr->next_hdr = IB_GRH_NEXT_HDR;
 664         hdr->hop_limit = grh->hop_limit;
 665         /* The SGID is 32-bit aligned. */
 666         hdr->sgid.global.subnet_prefix = ibp->gid_prefix;
 667         hdr->sgid.global.interface_id = grh->sgid_index ?
 668                 ibp->guids[grh->sgid_index - 1] : ppd_from_ibp(ibp)->guid;
 669         hdr->dgid = grh->dgid;
 670
 671         /* GRH header size in 32-bit words. */
 672         return sizeof(struct ib_grh) / sizeof(u32);
 673 }
 674
 675 void qib_make_ruc_header(struct qib_qp *qp, struct qib_other_headers *ohdr,
 676                          u32 bth0, u32 bth2)
 677 {
 678         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 679         u16 lrh0;
 680         u32 nwords;
 681         u32 extra_bytes;
 682
 683         /* Construct the header. */
 684         extra_bytes = -qp->s_cur_size & 3;
 685         nwords = (qp->s_cur_size + extra_bytes) >> 2;
 686         lrh0 = QIB_LRH_BTH;
 687         if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
 688                 qp->s_hdrwords += qib_make_grh(ibp, &qp->s_hdr->u.l.grh,
 689                                                &qp->remote_ah_attr.grh,
 690                                                qp->s_hdrwords, nwords);
 691                 lrh0 = QIB_LRH_GRH;
 692         }
 693         lrh0 |= ibp->sl_to_vl[qp->remote_ah_attr.sl] << 12 |
 694                 qp->remote_ah_attr.sl << 4;
 695         qp->s_hdr->lrh[0] = cpu_to_be16(lrh0);
 696         qp->s_hdr->lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
 697         qp->s_hdr->lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
 698         qp->s_hdr->lrh[3] = cpu_to_be16(ppd_from_ibp(ibp)->lid |
 699                                        qp->remote_ah_attr.src_path_bits);
 700         bth0 |= qib_get_pkey(ibp, qp->s_pkey_index);
 701         bth0 |= extra_bytes << 20;
 702         if (qp->s_mig_state == IB_MIG_MIGRATED)
 703                 bth0 |= IB_BTH_MIG_REQ;
 704         ohdr->bth[0] = cpu_to_be32(bth0);
 705         ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
 706         ohdr->bth[2] = cpu_to_be32(bth2);
 707         this_cpu_inc(ibp->pmastats->n_unicast_xmit);
 708 }
 709
 710 /**
 711  * qib_do_send - perform a send on a QP
 712  * @work: contains a pointer to the QP
 713  *
 714  * Process entries in the send work queue until credit or queue is
 715  * exhausted.  Only allow one CPU to send a packet per QP (tasklet).
 716  * Otherwise, two threads could send packets out of order.
 717  */
 718 void qib_do_send(struct work_struct *work)
 719 {
 720         struct qib_qp *qp = container_of(work, struct qib_qp, s_work);
 721         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 722         struct qib_pportdata *ppd = ppd_from_ibp(ibp);
 723         int (*make_req)(struct qib_qp *qp);
 724         unsigned long flags;
 725
 726         if ((qp->ibqp.qp_type == IB_QPT_RC ||
 727              qp->ibqp.qp_type == IB_QPT_UC) &&
 728             (qp->remote_ah_attr.dlid & ~((1 << ppd->lmc) - 1)) == ppd->lid) {
 729                 qib_ruc_loopback(qp);
 730                 return;
 731         }
 732
 733         if (qp->ibqp.qp_type == IB_QPT_RC)
 734                 make_req = qib_make_rc_req;
 735         else if (qp->ibqp.qp_type == IB_QPT_UC)
 736                 make_req = qib_make_uc_req;
 737         else
 738                 make_req = qib_make_ud_req;
 739
 740         spin_lock_irqsave(&qp->s_lock, flags);
 741
 742         /* Return if we are already busy processing a work request. */
 743         if (!qib_send_ok(qp)) {
 744                 spin_unlock_irqrestore(&qp->s_lock, flags);
 745                 return;
 746         }
 747
 748         qp->s_flags |= QIB_S_BUSY;
 749
 750         spin_unlock_irqrestore(&qp->s_lock, flags);
 751
 752         do {
 753                 /* Check for a constructed packet to be sent. */
 754                 if (qp->s_hdrwords != 0) {
 755                         /*
 756                          * If the packet cannot be sent now, return and
 757                          * the send tasklet will be woken up later.
 758                          */
 759                         if (qib_verbs_send(qp, qp->s_hdr, qp->s_hdrwords,
 760                                            qp->s_cur_sge, qp->s_cur_size))
 761                                 break;
 762                         /* Record that s_hdr is empty. */
 763                         qp->s_hdrwords = 0;
 764                 }
 765         } while (make_req(qp));
 766 }
 767
 768 /*
 769  * This should be called with s_lock held.
 770  */
 771 void qib_send_complete(struct qib_qp *qp, struct qib_swqe *wqe,
 772                        enum ib_wc_status status)
 773 {
 774         u32 old_last, last;
 775         unsigned i;
 776
 777         if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_OR_FLUSH_SEND))
 778                 return;
 779
 780         for (i = 0; i < wqe->wr.num_sge; i++) {
 781                 struct qib_sge *sge = &wqe->sg_list[i];
 782
 783                 qib_put_mr(sge->mr);
 784         }
 785         if (qp->ibqp.qp_type == IB_QPT_UD ||
 786             qp->ibqp.qp_type == IB_QPT_SMI ||
 787             qp->ibqp.qp_type == IB_QPT_GSI)
 788                 atomic_dec(&to_iah(wqe->ud_wr.ah)->refcount);
 789
 790         /* See ch. 11.2.4.1 and 10.7.3.1 */
 791         if (!(qp->s_flags & QIB_S_SIGNAL_REQ_WR) ||
 792             (wqe->wr.send_flags & IB_SEND_SIGNALED) ||
 793             status != IB_WC_SUCCESS) {
 794                 struct ib_wc wc;
 795
 796                 memset(&wc, 0, sizeof(wc));
 797                 wc.wr_id = wqe->wr.wr_id;
 798                 wc.status = status;
 799                 wc.opcode = ib_qib_wc_opcode[wqe->wr.opcode];
 800                 wc.qp = &qp->ibqp;
 801                 if (status == IB_WC_SUCCESS)
 802                         wc.byte_len = wqe->length;
 803                 qib_cq_enter(to_icq(qp->ibqp.send_cq), &wc,
 804                              status != IB_WC_SUCCESS);
 805         }
 806
 807         last = qp->s_last;
 808         old_last = last;
 809         if (++last >= qp->s_size)
 810                 last = 0;
 811         qp->s_last = last;
 812         if (qp->s_acked == old_last)
 813                 qp->s_acked = last;
 814         if (qp->s_cur == old_last)
 815                 qp->s_cur = last;
 816         if (qp->s_tail == old_last)
 817                 qp->s_tail = last;
 818         if (qp->state == IB_QPS_SQD && last == qp->s_cur)
 819                 qp->s_draining = 0;
 820 }