drivers/infiniband/hw/ipath/ipath_ruc.c

   1 /*
   2  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include "ipath_verbs.h"
  34
  35 /*
  36  * Convert the AETH RNR timeout code into the number of milliseconds.
  37  */
  38 const u32 ib_ipath_rnr_table[32] = {
  39         656,                    /* 0 */
  40         1,                      /* 1 */
  41         1,                      /* 2 */
  42         1,                      /* 3 */
  43         1,                      /* 4 */
  44         1,                      /* 5 */
  45         1,                      /* 6 */
  46         1,                      /* 7 */
  47         1,                      /* 8 */
  48         1,                      /* 9 */
  49         1,                      /* A */
  50         1,                      /* B */
  51         1,                      /* C */
  52         1,                      /* D */
  53         2,                      /* E */
  54         2,                      /* F */
  55         3,                      /* 10 */
  56         4,                      /* 11 */
  57         6,                      /* 12 */
  58         8,                      /* 13 */
  59         11,                     /* 14 */
  60         16,                     /* 15 */
  61         21,                     /* 16 */
  62         31,                     /* 17 */
  63         41,                     /* 18 */
  64         62,                     /* 19 */
  65         82,                     /* 1A */
  66         123,                    /* 1B */
  67         164,                    /* 1C */
  68         246,                    /* 1D */
  69         328,                    /* 1E */
  70         492                     /* 1F */
  71 };
  72
  73 /**
  74  * ipath_insert_rnr_queue - put QP on the RNR timeout list for the device
  75  * @qp: the QP
  76  *
  77  * XXX Use a simple list for now.  We might need a priority
  78  * queue if we have lots of QPs waiting for RNR timeouts
  79  * but that should be rare.
  80  */
  81 void ipath_insert_rnr_queue(struct ipath_qp *qp)
  82 {
  83         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
  84         unsigned long flags;
  85
  86         spin_lock_irqsave(&dev->pending_lock, flags);
  87         if (list_empty(&dev->rnrwait))
  88                 list_add(&qp->timerwait, &dev->rnrwait);
  89         else {
  90                 struct list_head *l = &dev->rnrwait;
  91                 struct ipath_qp *nqp = list_entry(l->next, struct ipath_qp,
  92                                                   timerwait);
  93
  94                 while (qp->s_rnr_timeout >= nqp->s_rnr_timeout) {
  95                         qp->s_rnr_timeout -= nqp->s_rnr_timeout;
  96                         l = l->next;
  97                         if (l->next == &dev->rnrwait)
  98                                 break;
  99                         nqp = list_entry(l->next, struct ipath_qp,
 100                                          timerwait);
 101                 }
 102                 list_add(&qp->timerwait, l);
 103         }
 104         spin_unlock_irqrestore(&dev->pending_lock, flags);
 105 }
 106
 107 /**
 108  * ipath_get_rwqe - copy the next RWQE into the QP's RWQE
 109  * @qp: the QP
 110  * @wr_id_only: update wr_id only, not SGEs
 111  *
 112  * Return 0 if no RWQE is available, otherwise return 1.
 113  *
 114  * Called at interrupt level with the QP r_rq.lock held.
 115  */
 116 int ipath_get_rwqe(struct ipath_qp *qp, int wr_id_only)
 117 {
 118         struct ipath_rq *rq;
 119         struct ipath_srq *srq;
 120         struct ipath_rwqe *wqe;
 121         int ret;
 122
 123         if (!qp->ibqp.srq) {
 124                 rq = &qp->r_rq;
 125                 if (unlikely(rq->tail == rq->head)) {
 126                         ret = 0;
 127                         goto bail;
 128                 }
 129                 wqe = get_rwqe_ptr(rq, rq->tail);
 130                 qp->r_wr_id = wqe->wr_id;
 131                 if (!wr_id_only) {
 132                         qp->r_sge.sge = wqe->sg_list[0];
 133                         qp->r_sge.sg_list = wqe->sg_list + 1;
 134                         qp->r_sge.num_sge = wqe->num_sge;
 135                         qp->r_len = wqe->length;
 136                 }
 137                 if (++rq->tail >= rq->size)
 138                         rq->tail = 0;
 139                 ret = 1;
 140                 goto bail;
 141         }
 142
 143         srq = to_isrq(qp->ibqp.srq);
 144         rq = &srq->rq;
 145         spin_lock(&rq->lock);
 146         if (unlikely(rq->tail == rq->head)) {
 147                 spin_unlock(&rq->lock);
 148                 ret = 0;
 149                 goto bail;
 150         }
 151         wqe = get_rwqe_ptr(rq, rq->tail);
 152         qp->r_wr_id = wqe->wr_id;
 153         if (!wr_id_only) {
 154                 qp->r_sge.sge = wqe->sg_list[0];
 155                 qp->r_sge.sg_list = wqe->sg_list + 1;
 156                 qp->r_sge.num_sge = wqe->num_sge;
 157                 qp->r_len = wqe->length;
 158         }
 159         if (++rq->tail >= rq->size)
 160                 rq->tail = 0;
 161         if (srq->ibsrq.event_handler) {
 162                 struct ib_event ev;
 163                 u32 n;
 164
 165                 if (rq->head < rq->tail)
 166                         n = rq->size + rq->head - rq->tail;
 167                 else
 168                         n = rq->head - rq->tail;
 169                 if (n < srq->limit) {
 170                         srq->limit = 0;
 171                         spin_unlock(&rq->lock);
 172                         ev.device = qp->ibqp.device;
 173                         ev.element.srq = qp->ibqp.srq;
 174                         ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
 175                         srq->ibsrq.event_handler(&ev,
 176                                                  srq->ibsrq.srq_context);
 177                 } else
 178                         spin_unlock(&rq->lock);
 179         } else
 180                 spin_unlock(&rq->lock);
 181         ret = 1;
 182
 183 bail:
 184         return ret;
 185 }
 186
 187 /**
 188  * ipath_ruc_loopback - handle UC and RC lookback requests
 189  * @sqp: the loopback QP
 190  * @wc: the work completion entry
 191  *
 192  * This is called from ipath_do_uc_send() or ipath_do_rc_send() to
 193  * forward a WQE addressed to the same HCA.
 194  * Note that although we are single threaded due to the tasklet, we still
 195  * have to protect against post_send().  We don't have to worry about
 196  * receive interrupts since this is a connected protocol and all packets
 197  * will pass through here.
 198  */
 199 void ipath_ruc_loopback(struct ipath_qp *sqp, struct ib_wc *wc)
 200 {
 201         struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
 202         struct ipath_qp *qp;
 203         struct ipath_swqe *wqe;
 204         struct ipath_sge *sge;
 205         unsigned long flags;
 206         u64 sdata;
 207
 208         qp = ipath_lookup_qpn(&dev->qp_table, sqp->remote_qpn);
 209         if (!qp) {
 210                 dev->n_pkt_drops++;
 211                 return;
 212         }
 213
 214 again:
 215         spin_lock_irqsave(&sqp->s_lock, flags);
 216
 217         if (!(ib_ipath_state_ops[sqp->state] & IPATH_PROCESS_SEND_OK)) {
 218                 spin_unlock_irqrestore(&sqp->s_lock, flags);
 219                 goto done;
 220         }
 221
 222         /* Get the next send request. */
 223         if (sqp->s_last == sqp->s_head) {
 224                 /* Send work queue is empty. */
 225                 spin_unlock_irqrestore(&sqp->s_lock, flags);
 226                 goto done;
 227         }
 228
 229         /*
 230          * We can rely on the entry not changing without the s_lock
 231          * being held until we update s_last.
 232          */
 233         wqe = get_swqe_ptr(sqp, sqp->s_last);
 234         spin_unlock_irqrestore(&sqp->s_lock, flags);
 235
 236         wc->wc_flags = 0;
 237         wc->imm_data = 0;
 238
 239         sqp->s_sge.sge = wqe->sg_list[0];
 240         sqp->s_sge.sg_list = wqe->sg_list + 1;
 241         sqp->s_sge.num_sge = wqe->wr.num_sge;
 242         sqp->s_len = wqe->length;
 243         switch (wqe->wr.opcode) {
 244         case IB_WR_SEND_WITH_IMM:
 245                 wc->wc_flags = IB_WC_WITH_IMM;
 246                 wc->imm_data = wqe->wr.imm_data;
 247                 /* FALLTHROUGH */
 248         case IB_WR_SEND:
 249                 spin_lock_irqsave(&qp->r_rq.lock, flags);
 250                 if (!ipath_get_rwqe(qp, 0)) {
 251                 rnr_nak:
 252                         spin_unlock_irqrestore(&qp->r_rq.lock, flags);
 253                         /* Handle RNR NAK */
 254                         if (qp->ibqp.qp_type == IB_QPT_UC)
 255                                 goto send_comp;
 256                         if (sqp->s_rnr_retry == 0) {
 257                                 wc->status = IB_WC_RNR_RETRY_EXC_ERR;
 258                                 goto err;
 259                         }
 260                         if (sqp->s_rnr_retry_cnt < 7)
 261                                 sqp->s_rnr_retry--;
 262                         dev->n_rnr_naks++;
 263                         sqp->s_rnr_timeout =
 264                                 ib_ipath_rnr_table[sqp->s_min_rnr_timer];
 265                         ipath_insert_rnr_queue(sqp);
 266                         goto done;
 267                 }
 268                 spin_unlock_irqrestore(&qp->r_rq.lock, flags);
 269                 break;
 270
 271         case IB_WR_RDMA_WRITE_WITH_IMM:
 272                 wc->wc_flags = IB_WC_WITH_IMM;
 273                 wc->imm_data = wqe->wr.imm_data;
 274                 spin_lock_irqsave(&qp->r_rq.lock, flags);
 275                 if (!ipath_get_rwqe(qp, 1))
 276                         goto rnr_nak;
 277                 spin_unlock_irqrestore(&qp->r_rq.lock, flags);
 278                 /* FALLTHROUGH */
 279         case IB_WR_RDMA_WRITE:
 280                 if (wqe->length == 0)
 281                         break;
 282                 if (unlikely(!ipath_rkey_ok(dev, &qp->r_sge, wqe->length,
 283                                             wqe->wr.wr.rdma.remote_addr,
 284                                             wqe->wr.wr.rdma.rkey,
 285                                             IB_ACCESS_REMOTE_WRITE))) {
 286                 acc_err:
 287                         wc->status = IB_WC_REM_ACCESS_ERR;
 288                 err:
 289                         wc->wr_id = wqe->wr.wr_id;
 290                         wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
 291                         wc->vendor_err = 0;
 292                         wc->byte_len = 0;
 293                         wc->qp_num = sqp->ibqp.qp_num;
 294                         wc->src_qp = sqp->remote_qpn;
 295                         wc->pkey_index = 0;
 296                         wc->slid = sqp->remote_ah_attr.dlid;
 297                         wc->sl = sqp->remote_ah_attr.sl;
 298                         wc->dlid_path_bits = 0;
 299                         wc->port_num = 0;
 300                         ipath_sqerror_qp(sqp, wc);
 301                         goto done;
 302                 }
 303                 break;
 304
 305         case IB_WR_RDMA_READ:
 306                 if (unlikely(!ipath_rkey_ok(dev, &sqp->s_sge, wqe->length,
 307                                             wqe->wr.wr.rdma.remote_addr,
 308                                             wqe->wr.wr.rdma.rkey,
 309                                             IB_ACCESS_REMOTE_READ)))
 310                         goto acc_err;
 311                 if (unlikely(!(qp->qp_access_flags &
 312                                IB_ACCESS_REMOTE_READ)))
 313                         goto acc_err;
 314                 qp->r_sge.sge = wqe->sg_list[0];
 315                 qp->r_sge.sg_list = wqe->sg_list + 1;
 316                 qp->r_sge.num_sge = wqe->wr.num_sge;
 317                 break;
 318
 319         case IB_WR_ATOMIC_CMP_AND_SWP:
 320         case IB_WR_ATOMIC_FETCH_AND_ADD:
 321                 if (unlikely(!ipath_rkey_ok(dev, &qp->r_sge, sizeof(u64),
 322                                             wqe->wr.wr.rdma.remote_addr,
 323                                             wqe->wr.wr.rdma.rkey,
 324                                             IB_ACCESS_REMOTE_ATOMIC)))
 325                         goto acc_err;
 326                 /* Perform atomic OP and save result. */
 327                 sdata = wqe->wr.wr.atomic.swap;
 328                 spin_lock_irqsave(&dev->pending_lock, flags);
 329                 qp->r_atomic_data = *(u64 *) qp->r_sge.sge.vaddr;
 330                 if (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
 331                         *(u64 *) qp->r_sge.sge.vaddr =
 332                                 qp->r_atomic_data + sdata;
 333                 else if (qp->r_atomic_data == wqe->wr.wr.atomic.compare_add)
 334                         *(u64 *) qp->r_sge.sge.vaddr = sdata;
 335                 spin_unlock_irqrestore(&dev->pending_lock, flags);
 336                 *(u64 *) sqp->s_sge.sge.vaddr = qp->r_atomic_data;
 337                 goto send_comp;
 338
 339         default:
 340                 goto done;
 341         }
 342
 343         sge = &sqp->s_sge.sge;
 344         while (sqp->s_len) {
 345                 u32 len = sqp->s_len;
 346
 347                 if (len > sge->length)
 348                         len = sge->length;
 349                 BUG_ON(len == 0);
 350                 ipath_copy_sge(&qp->r_sge, sge->vaddr, len);
 351                 sge->vaddr += len;
 352                 sge->length -= len;
 353                 sge->sge_length -= len;
 354                 if (sge->sge_length == 0) {
 355                         if (--sqp->s_sge.num_sge)
 356                                 *sge = *sqp->s_sge.sg_list++;
 357                 } else if (sge->length == 0 && sge->mr != NULL) {
 358                         if (++sge->n >= IPATH_SEGSZ) {
 359                                 if (++sge->m >= sge->mr->mapsz)
 360                                         break;
 361                                 sge->n = 0;
 362                         }
 363                         sge->vaddr =
 364                                 sge->mr->map[sge->m]->segs[sge->n].vaddr;
 365                         sge->length =
 366                                 sge->mr->map[sge->m]->segs[sge->n].length;
 367                 }
 368                 sqp->s_len -= len;
 369         }
 370
 371         if (wqe->wr.opcode == IB_WR_RDMA_WRITE ||
 372             wqe->wr.opcode == IB_WR_RDMA_READ)
 373                 goto send_comp;
 374
 375         if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
 376                 wc->opcode = IB_WC_RECV_RDMA_WITH_IMM;
 377         else
 378                 wc->opcode = IB_WC_RECV;
 379         wc->wr_id = qp->r_wr_id;
 380         wc->status = IB_WC_SUCCESS;
 381         wc->vendor_err = 0;
 382         wc->byte_len = wqe->length;
 383         wc->qp_num = qp->ibqp.qp_num;
 384         wc->src_qp = qp->remote_qpn;
 385         /* XXX do we know which pkey matched? Only needed for GSI. */
 386         wc->pkey_index = 0;
 387         wc->slid = qp->remote_ah_attr.dlid;
 388         wc->sl = qp->remote_ah_attr.sl;
 389         wc->dlid_path_bits = 0;
 390         /* Signal completion event if the solicited bit is set. */
 391         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), wc,
 392                        wqe->wr.send_flags & IB_SEND_SOLICITED);
 393
 394 send_comp:
 395         sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
 396
 397         if (!test_bit(IPATH_S_SIGNAL_REQ_WR, &sqp->s_flags) ||
 398             (wqe->wr.send_flags & IB_SEND_SIGNALED)) {
 399                 wc->wr_id = wqe->wr.wr_id;
 400                 wc->status = IB_WC_SUCCESS;
 401                 wc->opcode = ib_ipath_wc_opcode[wqe->wr.opcode];
 402                 wc->vendor_err = 0;
 403                 wc->byte_len = wqe->length;
 404                 wc->qp_num = sqp->ibqp.qp_num;
 405                 wc->src_qp = 0;
 406                 wc->pkey_index = 0;
 407                 wc->slid = 0;
 408                 wc->sl = 0;
 409                 wc->dlid_path_bits = 0;
 410                 wc->port_num = 0;
 411                 ipath_cq_enter(to_icq(sqp->ibqp.send_cq), wc, 0);
 412         }
 413
 414         /* Update s_last now that we are finished with the SWQE */
 415         spin_lock_irqsave(&sqp->s_lock, flags);
 416         if (++sqp->s_last >= sqp->s_size)
 417                 sqp->s_last = 0;
 418         spin_unlock_irqrestore(&sqp->s_lock, flags);
 419         goto again;
 420
 421 done:
 422         if (atomic_dec_and_test(&qp->refcount))
 423                 wake_up(&qp->wait);
 424 }
 425
 426 /**
 427  * ipath_no_bufs_available - tell the layer driver we need buffers
 428  * @qp: the QP that caused the problem
 429  * @dev: the device we ran out of buffers on
 430  *
 431  * Called when we run out of PIO buffers.
 432  */
 433 void ipath_no_bufs_available(struct ipath_qp *qp, struct ipath_ibdev *dev)
 434 {
 435         unsigned long flags;
 436
 437         spin_lock_irqsave(&dev->pending_lock, flags);
 438         if (list_empty(&qp->piowait))
 439                 list_add_tail(&qp->piowait, &dev->piowait);
 440         spin_unlock_irqrestore(&dev->pending_lock, flags);
 441         /*
 442          * Note that as soon as ipath_layer_want_buffer() is called and
 443          * possibly before it returns, ipath_ib_piobufavail()
 444          * could be called.  If we are still in the tasklet function,
 445          * tasklet_hi_schedule() will not call us until the next time
 446          * tasklet_hi_schedule() is called.
 447          * We clear the tasklet flag now since we are committing to return
 448          * from the tasklet function.
 449          */
 450         clear_bit(IPATH_S_BUSY, &qp->s_flags);
 451         tasklet_unlock(&qp->s_task);
 452         ipath_layer_want_buffer(dev->dd);
 453         dev->n_piowait++;
 454 }
 455
 456 /**
 457  * ipath_post_rc_send - post RC and UC sends
 458  * @qp: the QP to post on
 459  * @wr: the work request to send
 460  */
 461 int ipath_post_rc_send(struct ipath_qp *qp, struct ib_send_wr *wr)
 462 {
 463         struct ipath_swqe *wqe;
 464         unsigned long flags;
 465         u32 next;
 466         int i, j;
 467         int acc;
 468         int ret;
 469
 470         /*
 471          * Don't allow RDMA reads or atomic operations on UC or
 472          * undefined operations.
 473          * Make sure buffer is large enough to hold the result for atomics.
 474          */
 475         if (qp->ibqp.qp_type == IB_QPT_UC) {
 476                 if ((unsigned) wr->opcode >= IB_WR_RDMA_READ) {
 477                         ret = -EINVAL;
 478                         goto bail;
 479                 }
 480         } else if ((unsigned) wr->opcode > IB_WR_ATOMIC_FETCH_AND_ADD) {
 481                 ret = -EINVAL;
 482                 goto bail;
 483         } else if (wr->opcode >= IB_WR_ATOMIC_CMP_AND_SWP &&
 484                    (wr->num_sge == 0 ||
 485                     wr->sg_list[0].length < sizeof(u64) ||
 486                     wr->sg_list[0].addr & (sizeof(u64) - 1))) {
 487                 ret = -EINVAL;
 488                 goto bail;
 489         }
 490         /* IB spec says that num_sge == 0 is OK. */
 491         if (wr->num_sge > qp->s_max_sge) {
 492                 ret = -ENOMEM;
 493                 goto bail;
 494         }
 495         spin_lock_irqsave(&qp->s_lock, flags);
 496         next = qp->s_head + 1;
 497         if (next >= qp->s_size)
 498                 next = 0;
 499         if (next == qp->s_last) {
 500                 spin_unlock_irqrestore(&qp->s_lock, flags);
 501                 ret = -EINVAL;
 502                 goto bail;
 503         }
 504
 505         wqe = get_swqe_ptr(qp, qp->s_head);
 506         wqe->wr = *wr;
 507         wqe->ssn = qp->s_ssn++;
 508         wqe->sg_list[0].mr = NULL;
 509         wqe->sg_list[0].vaddr = NULL;
 510         wqe->sg_list[0].length = 0;
 511         wqe->sg_list[0].sge_length = 0;
 512         wqe->length = 0;
 513         acc = wr->opcode >= IB_WR_RDMA_READ ? IB_ACCESS_LOCAL_WRITE : 0;
 514         for (i = 0, j = 0; i < wr->num_sge; i++) {
 515                 if (to_ipd(qp->ibqp.pd)->user && wr->sg_list[i].lkey == 0) {
 516                         spin_unlock_irqrestore(&qp->s_lock, flags);
 517                         ret = -EINVAL;
 518                         goto bail;
 519                 }
 520                 if (wr->sg_list[i].length == 0)
 521                         continue;
 522                 if (!ipath_lkey_ok(&to_idev(qp->ibqp.device)->lk_table,
 523                                    &wqe->sg_list[j], &wr->sg_list[i],
 524                                    acc)) {
 525                         spin_unlock_irqrestore(&qp->s_lock, flags);
 526                         ret = -EINVAL;
 527                         goto bail;
 528                 }
 529                 wqe->length += wr->sg_list[i].length;
 530                 j++;
 531         }
 532         wqe->wr.num_sge = j;
 533         qp->s_head = next;
 534         spin_unlock_irqrestore(&qp->s_lock, flags);
 535
 536         if (qp->ibqp.qp_type == IB_QPT_UC)
 537                 ipath_do_uc_send((unsigned long) qp);
 538         else
 539                 ipath_do_rc_send((unsigned long) qp);
 540
 541         ret = 0;
 542
 543 bail:
 544         return ret;
 545 }