drivers/infiniband/hw/qib/qib_qp.c

   1 /*
   2  * Copyright (c) 2006, 2007, 2008, 2009, 2010 QLogic Corporation.
   3  * All rights reserved.
   4  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34
  35 #include <linux/err.h>
  36 #include <linux/vmalloc.h>
  37 #include <linux/jhash.h>
  38
  39 #include "qib.h"
  40
  41 #define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
  42 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
  43
  44 static inline unsigned mk_qpn(struct qib_qpn_table *qpt,
  45                               struct qpn_map *map, unsigned off)
  46 {
  47         return (map - qpt->map) * BITS_PER_PAGE + off;
  48 }
  49
  50 static inline unsigned find_next_offset(struct qib_qpn_table *qpt,
  51                                         struct qpn_map *map, unsigned off,
  52                                         unsigned n)
  53 {
  54         if (qpt->mask) {
  55                 off++;
  56                 if (((off & qpt->mask) >> 1) >= n)
  57                         off = (off | qpt->mask) + 2;
  58         } else
  59                 off = find_next_zero_bit(map->page, BITS_PER_PAGE, off);
  60         return off;
  61 }
  62
  63 /*
  64  * Convert the AETH credit code into the number of credits.
  65  */
  66 static u32 credit_table[31] = {
  67         0,                      /* 0 */
  68         1,                      /* 1 */
  69         2,                      /* 2 */
  70         3,                      /* 3 */
  71         4,                      /* 4 */
  72         6,                      /* 5 */
  73         8,                      /* 6 */
  74         12,                     /* 7 */
  75         16,                     /* 8 */
  76         24,                     /* 9 */
  77         32,                     /* A */
  78         48,                     /* B */
  79         64,                     /* C */
  80         96,                     /* D */
  81         128,                    /* E */
  82         192,                    /* F */
  83         256,                    /* 10 */
  84         384,                    /* 11 */
  85         512,                    /* 12 */
  86         768,                    /* 13 */
  87         1024,                   /* 14 */
  88         1536,                   /* 15 */
  89         2048,                   /* 16 */
  90         3072,                   /* 17 */
  91         4096,                   /* 18 */
  92         6144,                   /* 19 */
  93         8192,                   /* 1A */
  94         12288,                  /* 1B */
  95         16384,                  /* 1C */
  96         24576,                  /* 1D */
  97         32768                   /* 1E */
  98 };
  99
 100 static void get_map_page(struct qib_qpn_table *qpt, struct qpn_map *map)
 101 {
 102         unsigned long page = get_zeroed_page(GFP_KERNEL);
 103
 104         /*
 105          * Free the page if someone raced with us installing it.
 106          */
 107
 108         spin_lock(&qpt->lock);
 109         if (map->page)
 110                 free_page(page);
 111         else
 112                 map->page = (void *)page;
 113         spin_unlock(&qpt->lock);
 114 }
 115
 116 /*
 117  * Allocate the next available QPN or
 118  * zero/one for QP type IB_QPT_SMI/IB_QPT_GSI.
 119  */
 120 static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
 121                      enum ib_qp_type type, u8 port)
 122 {
 123         u32 i, offset, max_scan, qpn;
 124         struct qpn_map *map;
 125         u32 ret;
 126
 127         if (type == IB_QPT_SMI || type == IB_QPT_GSI) {
 128                 unsigned n;
 129
 130                 ret = type == IB_QPT_GSI;
 131                 n = 1 << (ret + 2 * (port - 1));
 132                 spin_lock(&qpt->lock);
 133                 if (qpt->flags & n)
 134                         ret = -EINVAL;
 135                 else
 136                         qpt->flags |= n;
 137                 spin_unlock(&qpt->lock);
 138                 goto bail;
 139         }
 140
 141         qpn = qpt->last + 2;
 142         if (qpn >= QPN_MAX)
 143                 qpn = 2;
 144         if (qpt->mask && ((qpn & qpt->mask) >> 1) >= dd->n_krcv_queues)
 145                 qpn = (qpn | qpt->mask) + 2;
 146         offset = qpn & BITS_PER_PAGE_MASK;
 147         map = &qpt->map[qpn / BITS_PER_PAGE];
 148         max_scan = qpt->nmaps - !offset;
 149         for (i = 0;;) {
 150                 if (unlikely(!map->page)) {
 151                         get_map_page(qpt, map);
 152                         if (unlikely(!map->page))
 153                                 break;
 154                 }
 155                 do {
 156                         if (!test_and_set_bit(offset, map->page)) {
 157                                 qpt->last = qpn;
 158                                 ret = qpn;
 159                                 goto bail;
 160                         }
 161                         offset = find_next_offset(qpt, map, offset,
 162                                 dd->n_krcv_queues);
 163                         qpn = mk_qpn(qpt, map, offset);
 164                         /*
 165                          * This test differs from alloc_pidmap().
 166                          * If find_next_offset() does find a zero
 167                          * bit, we don't need to check for QPN
 168                          * wrapping around past our starting QPN.
 169                          * We just need to be sure we don't loop
 170                          * forever.
 171                          */
 172                 } while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
 173                 /*
 174                  * In order to keep the number of pages allocated to a
 175                  * minimum, we scan the all existing pages before increasing
 176                  * the size of the bitmap table.
 177                  */
 178                 if (++i > max_scan) {
 179                         if (qpt->nmaps == QPNMAP_ENTRIES)
 180                                 break;
 181                         map = &qpt->map[qpt->nmaps++];
 182                         offset = 0;
 183                 } else if (map < &qpt->map[qpt->nmaps]) {
 184                         ++map;
 185                         offset = 0;
 186                 } else {
 187                         map = &qpt->map[0];
 188                         offset = 2;
 189                 }
 190                 qpn = mk_qpn(qpt, map, offset);
 191         }
 192
 193         ret = -ENOMEM;
 194
 195 bail:
 196         return ret;
 197 }
 198
 199 static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
 200 {
 201         struct qpn_map *map;
 202
 203         map = qpt->map + qpn / BITS_PER_PAGE;
 204         if (map->page)
 205                 clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
 206 }
 207
 208 static inline unsigned qpn_hash(struct qib_ibdev *dev, u32 qpn)
 209 {
 210         return jhash_1word(qpn, dev->qp_rnd) &
 211                 (dev->qp_table_size - 1);
 212 }
 213
 214
 215 /*
 216  * Put the QP into the hash table.
 217  * The hash table holds a reference to the QP.
 218  */
 219 static void insert_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 220 {
 221         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 222         unsigned long flags;
 223         unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 224
 225         spin_lock_irqsave(&dev->qpt_lock, flags);
 226         atomic_inc(&qp->refcount);
 227
 228         if (qp->ibqp.qp_num == 0)
 229                 rcu_assign_pointer(ibp->qp0, qp);
 230         else if (qp->ibqp.qp_num == 1)
 231                 rcu_assign_pointer(ibp->qp1, qp);
 232         else {
 233                 qp->next = dev->qp_table[n];
 234                 rcu_assign_pointer(dev->qp_table[n], qp);
 235         }
 236
 237         spin_unlock_irqrestore(&dev->qpt_lock, flags);
 238         synchronize_rcu();
 239 }
 240
 241 /*
 242  * Remove the QP from the table so it can't be found asynchronously by
 243  * the receive interrupt routine.
 244  */
 245 static void remove_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 246 {
 247         struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
 248         unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 249         unsigned long flags;
 250
 251         spin_lock_irqsave(&dev->qpt_lock, flags);
 252
 253         if (ibp->qp0 == qp) {
 254                 atomic_dec(&qp->refcount);
 255                 rcu_assign_pointer(ibp->qp0, NULL);
 256         } else if (ibp->qp1 == qp) {
 257                 atomic_dec(&qp->refcount);
 258                 rcu_assign_pointer(ibp->qp1, NULL);
 259         } else {
 260                 struct qib_qp *q, **qpp;
 261
 262                 qpp = &dev->qp_table[n];
 263                 for (; (q = *qpp) != NULL; qpp = &q->next)
 264                         if (q == qp) {
 265                                 atomic_dec(&qp->refcount);
 266                                 rcu_assign_pointer(*qpp, qp->next);
 267                                 qp->next = NULL;
 268                                 break;
 269                         }
 270         }
 271
 272         spin_unlock_irqrestore(&dev->qpt_lock, flags);
 273         synchronize_rcu();
 274 }
 275
 276 /**
 277  * qib_free_all_qps - check for QPs still in use
 278  * @qpt: the QP table to empty
 279  *
 280  * There should not be any QPs still in use.
 281  * Free memory for table.
 282  */
 283 unsigned qib_free_all_qps(struct qib_devdata *dd)
 284 {
 285         struct qib_ibdev *dev = &dd->verbs_dev;
 286         unsigned long flags;
 287         struct qib_qp *qp;
 288         unsigned n, qp_inuse = 0;
 289
 290         for (n = 0; n < dd->num_pports; n++) {
 291                 struct qib_ibport *ibp = &dd->pport[n].ibport_data;
 292
 293                 if (!qib_mcast_tree_empty(ibp))
 294                         qp_inuse++;
 295                 rcu_read_lock();
 296                 if (rcu_dereference(ibp->qp0))
 297                         qp_inuse++;
 298                 if (rcu_dereference(ibp->qp1))
 299                         qp_inuse++;
 300                 rcu_read_unlock();
 301         }
 302
 303         spin_lock_irqsave(&dev->qpt_lock, flags);
 304         for (n = 0; n < dev->qp_table_size; n++) {
 305                 qp = dev->qp_table[n];
 306                 rcu_assign_pointer(dev->qp_table[n], NULL);
 307
 308                 for (; qp; qp = qp->next)
 309                         qp_inuse++;
 310         }
 311         spin_unlock_irqrestore(&dev->qpt_lock, flags);
 312         synchronize_rcu();
 313
 314         return qp_inuse;
 315 }
 316
 317 /**
 318  * qib_lookup_qpn - return the QP with the given QPN
 319  * @qpt: the QP table
 320  * @qpn: the QP number to look up
 321  *
 322  * The caller is responsible for decrementing the QP reference count
 323  * when done.
 324  */
 325 struct qib_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
 326 {
 327         struct qib_qp *qp = NULL;
 328
 329         if (unlikely(qpn <= 1)) {
 330                 rcu_read_lock();
 331                 if (qpn == 0)
 332                         qp = rcu_dereference(ibp->qp0);
 333                 else
 334                         qp = rcu_dereference(ibp->qp1);
 335         } else {
 336                 struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
 337                 unsigned n = qpn_hash(dev, qpn);
 338
 339                 rcu_read_lock();
 340                 for (qp = dev->qp_table[n]; rcu_dereference(qp); qp = qp->next)
 341                         if (qp->ibqp.qp_num == qpn)
 342                                 break;
 343         }
 344         if (qp)
 345                 if (unlikely(!atomic_inc_not_zero(&qp->refcount)))
 346                         qp = NULL;
 347
 348         rcu_read_unlock();
 349         return qp;
 350 }
 351
 352 /**
 353  * qib_reset_qp - initialize the QP state to the reset state
 354  * @qp: the QP to reset
 355  * @type: the QP type
 356  */
 357 static void qib_reset_qp(struct qib_qp *qp, enum ib_qp_type type)
 358 {
 359         qp->remote_qpn = 0;
 360         qp->qkey = 0;
 361         qp->qp_access_flags = 0;
 362         atomic_set(&qp->s_dma_busy, 0);
 363         qp->s_flags &= QIB_S_SIGNAL_REQ_WR;
 364         qp->s_hdrwords = 0;
 365         qp->s_wqe = NULL;
 366         qp->s_draining = 0;
 367         qp->s_next_psn = 0;
 368         qp->s_last_psn = 0;
 369         qp->s_sending_psn = 0;
 370         qp->s_sending_hpsn = 0;
 371         qp->s_psn = 0;
 372         qp->r_psn = 0;
 373         qp->r_msn = 0;
 374         if (type == IB_QPT_RC) {
 375                 qp->s_state = IB_OPCODE_RC_SEND_LAST;
 376                 qp->r_state = IB_OPCODE_RC_SEND_LAST;
 377         } else {
 378                 qp->s_state = IB_OPCODE_UC_SEND_LAST;
 379                 qp->r_state = IB_OPCODE_UC_SEND_LAST;
 380         }
 381         qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
 382         qp->r_nak_state = 0;
 383         qp->r_aflags = 0;
 384         qp->r_flags = 0;
 385         qp->s_head = 0;
 386         qp->s_tail = 0;
 387         qp->s_cur = 0;
 388         qp->s_acked = 0;
 389         qp->s_last = 0;
 390         qp->s_ssn = 1;
 391         qp->s_lsn = 0;
 392         qp->s_mig_state = IB_MIG_MIGRATED;
 393         memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
 394         qp->r_head_ack_queue = 0;
 395         qp->s_tail_ack_queue = 0;
 396         qp->s_num_rd_atomic = 0;
 397         if (qp->r_rq.wq) {
 398                 qp->r_rq.wq->head = 0;
 399                 qp->r_rq.wq->tail = 0;
 400         }
 401         qp->r_sge.num_sge = 0;
 402 }
 403
 404 static void clear_mr_refs(struct qib_qp *qp, int clr_sends)
 405 {
 406         unsigned n;
 407
 408         if (test_and_clear_bit(QIB_R_REWIND_SGE, &qp->r_aflags))
 409                 while (qp->s_rdma_read_sge.num_sge) {
 410                         atomic_dec(&qp->s_rdma_read_sge.sge.mr->refcount);
 411                         if (--qp->s_rdma_read_sge.num_sge)
 412                                 qp->s_rdma_read_sge.sge =
 413                                         *qp->s_rdma_read_sge.sg_list++;
 414                 }
 415
 416         while (qp->r_sge.num_sge) {
 417                 atomic_dec(&qp->r_sge.sge.mr->refcount);
 418                 if (--qp->r_sge.num_sge)
 419                         qp->r_sge.sge = *qp->r_sge.sg_list++;
 420         }
 421
 422         if (clr_sends) {
 423                 while (qp->s_last != qp->s_head) {
 424                         struct qib_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
 425                         unsigned i;
 426
 427                         for (i = 0; i < wqe->wr.num_sge; i++) {
 428                                 struct qib_sge *sge = &wqe->sg_list[i];
 429
 430                                 atomic_dec(&sge->mr->refcount);
 431                         }
 432                         if (qp->ibqp.qp_type == IB_QPT_UD ||
 433                             qp->ibqp.qp_type == IB_QPT_SMI ||
 434                             qp->ibqp.qp_type == IB_QPT_GSI)
 435                                 atomic_dec(&to_iah(wqe->wr.wr.ud.ah)->refcount);
 436                         if (++qp->s_last >= qp->s_size)
 437                                 qp->s_last = 0;
 438                 }
 439                 if (qp->s_rdma_mr) {
 440                         atomic_dec(&qp->s_rdma_mr->refcount);
 441                         qp->s_rdma_mr = NULL;
 442                 }
 443         }
 444
 445         if (qp->ibqp.qp_type != IB_QPT_RC)
 446                 return;
 447
 448         for (n = 0; n < ARRAY_SIZE(qp->s_ack_queue); n++) {
 449                 struct qib_ack_entry *e = &qp->s_ack_queue[n];
 450
 451                 if (e->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST &&
 452                     e->rdma_sge.mr) {
 453                         atomic_dec(&e->rdma_sge.mr->refcount);
 454                         e->rdma_sge.mr = NULL;
 455                 }
 456         }
 457 }
 458
 459 /**
 460  * qib_error_qp - put a QP into the error state
 461  * @qp: the QP to put into the error state
 462  * @err: the receive completion error to signal if a RWQE is active
 463  *
 464  * Flushes both send and receive work queues.
 465  * Returns true if last WQE event should be generated.
 466  * The QP r_lock and s_lock should be held and interrupts disabled.
 467  * If we are already in error state, just return.
 468  */
 469 int qib_error_qp(struct qib_qp *qp, enum ib_wc_status err)
 470 {
 471         struct qib_ibdev *dev = to_idev(qp->ibqp.device);
 472         struct ib_wc wc;
 473         int ret = 0;
 474
 475         if (qp->state == IB_QPS_ERR || qp->state == IB_QPS_RESET)
 476                 goto bail;
 477
 478         qp->state = IB_QPS_ERR;
 479
 480         if (qp->s_flags & (QIB_S_TIMER | QIB_S_WAIT_RNR)) {
 481                 qp->s_flags &= ~(QIB_S_TIMER | QIB_S_WAIT_RNR);
 482                 del_timer(&qp->s_timer);
 483         }
 484
 485         if (qp->s_flags & QIB_S_ANY_WAIT_SEND)
 486                 qp->s_flags &= ~QIB_S_ANY_WAIT_SEND;
 487
 488         spin_lock(&dev->pending_lock);
 489         if (!list_empty(&qp->iowait) && !(qp->s_flags & QIB_S_BUSY)) {
 490                 qp->s_flags &= ~QIB_S_ANY_WAIT_IO;
 491                 list_del_init(&qp->iowait);
 492         }
 493         spin_unlock(&dev->pending_lock);
 494
 495         if (!(qp->s_flags & QIB_S_BUSY)) {
 496                 qp->s_hdrwords = 0;
 497                 if (qp->s_rdma_mr) {
 498                         atomic_dec(&qp->s_rdma_mr->refcount);
 499                         qp->s_rdma_mr = NULL;
 500                 }
 501                 if (qp->s_tx) {
 502                         qib_put_txreq(qp->s_tx);
 503                         qp->s_tx = NULL;
 504                 }
 505         }
 506
 507         /* Schedule the sending tasklet to drain the send work queue. */
 508         if (qp->s_last != qp->s_head)
 509                 qib_schedule_send(qp);
 510
 511         clear_mr_refs(qp, 0);
 512
 513         memset(&wc, 0, sizeof(wc));
 514         wc.qp = &qp->ibqp;
 515         wc.opcode = IB_WC_RECV;
 516
 517         if (test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags)) {
 518                 wc.wr_id = qp->r_wr_id;
 519                 wc.status = err;
 520                 qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 521         }
 522         wc.status = IB_WC_WR_FLUSH_ERR;
 523
 524         if (qp->r_rq.wq) {
 525                 struct qib_rwq *wq;
 526                 u32 head;
 527                 u32 tail;
 528
 529                 spin_lock(&qp->r_rq.lock);
 530
 531                 /* sanity check pointers before trusting them */
 532                 wq = qp->r_rq.wq;
 533                 head = wq->head;
 534                 if (head >= qp->r_rq.size)
 535                         head = 0;
 536                 tail = wq->tail;
 537                 if (tail >= qp->r_rq.size)
 538                         tail = 0;
 539                 while (tail != head) {
 540                         wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
 541                         if (++tail >= qp->r_rq.size)
 542                                 tail = 0;
 543                         qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 544                 }
 545                 wq->tail = tail;
 546
 547                 spin_unlock(&qp->r_rq.lock);
 548         } else if (qp->ibqp.event_handler)
 549                 ret = 1;
 550
 551 bail:
 552         return ret;
 553 }
 554
 555 /**
 556  * qib_modify_qp - modify the attributes of a queue pair
 557  * @ibqp: the queue pair who's attributes we're modifying
 558  * @attr: the new attributes
 559  * @attr_mask: the mask of attributes to modify
 560  * @udata: user data for libibverbs.so
 561  *
 562  * Returns 0 on success, otherwise returns an errno.
 563  */
 564 int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 565                   int attr_mask, struct ib_udata *udata)
 566 {
 567         struct qib_ibdev *dev = to_idev(ibqp->device);
 568         struct qib_qp *qp = to_iqp(ibqp);
 569         enum ib_qp_state cur_state, new_state;
 570         struct ib_event ev;
 571         int lastwqe = 0;
 572         int mig = 0;
 573         int ret;
 574         u32 pmtu = 0; /* for gcc warning only */
 575
 576         spin_lock_irq(&qp->r_lock);
 577         spin_lock(&qp->s_lock);
 578
 579         cur_state = attr_mask & IB_QP_CUR_STATE ?
 580                 attr->cur_qp_state : qp->state;
 581         new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
 582
 583         if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
 584                                 attr_mask))
 585                 goto inval;
 586
 587         if (attr_mask & IB_QP_AV) {
 588                 if (attr->ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
 589                         goto inval;
 590                 if (qib_check_ah(qp->ibqp.device, &attr->ah_attr))
 591                         goto inval;
 592         }
 593
 594         if (attr_mask & IB_QP_ALT_PATH) {
 595                 if (attr->alt_ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
 596                         goto inval;
 597                 if (qib_check_ah(qp->ibqp.device, &attr->alt_ah_attr))
 598                         goto inval;
 599                 if (attr->alt_pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
 600                         goto inval;
 601         }
 602
 603         if (attr_mask & IB_QP_PKEY_INDEX)
 604                 if (attr->pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
 605                         goto inval;
 606
 607         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 608                 if (attr->min_rnr_timer > 31)
 609                         goto inval;
 610
 611         if (attr_mask & IB_QP_PORT)
 612                 if (qp->ibqp.qp_type == IB_QPT_SMI ||
 613                     qp->ibqp.qp_type == IB_QPT_GSI ||
 614                     attr->port_num == 0 ||
 615                     attr->port_num > ibqp->device->phys_port_cnt)
 616                         goto inval;
 617
 618         if (attr_mask & IB_QP_DEST_QPN)
 619                 if (attr->dest_qp_num > QIB_QPN_MASK)
 620                         goto inval;
 621
 622         if (attr_mask & IB_QP_RETRY_CNT)
 623                 if (attr->retry_cnt > 7)
 624                         goto inval;
 625
 626         if (attr_mask & IB_QP_RNR_RETRY)
 627                 if (attr->rnr_retry > 7)
 628                         goto inval;
 629
 630         /*
 631          * Don't allow invalid path_mtu values.  OK to set greater
 632          * than the active mtu (or even the max_cap, if we have tuned
 633          * that to a small mtu.  We'll set qp->path_mtu
 634          * to the lesser of requested attribute mtu and active,
 635          * for packetizing messages.
 636          * Note that the QP port has to be set in INIT and MTU in RTR.
 637          */
 638         if (attr_mask & IB_QP_PATH_MTU) {
 639                 struct qib_devdata *dd = dd_from_dev(dev);
 640                 int mtu, pidx = qp->port_num - 1;
 641
 642                 mtu = ib_mtu_enum_to_int(attr->path_mtu);
 643                 if (mtu == -1)
 644                         goto inval;
 645                 if (mtu > dd->pport[pidx].ibmtu) {
 646                         switch (dd->pport[pidx].ibmtu) {
 647                         case 4096:
 648                                 pmtu = IB_MTU_4096;
 649                                 break;
 650                         case 2048:
 651                                 pmtu = IB_MTU_2048;
 652                                 break;
 653                         case 1024:
 654                                 pmtu = IB_MTU_1024;
 655                                 break;
 656                         case 512:
 657                                 pmtu = IB_MTU_512;
 658                                 break;
 659                         case 256:
 660                                 pmtu = IB_MTU_256;
 661                                 break;
 662                         default:
 663                                 pmtu = IB_MTU_2048;
 664                         }
 665                 } else
 666                         pmtu = attr->path_mtu;
 667         }
 668
 669         if (attr_mask & IB_QP_PATH_MIG_STATE) {
 670                 if (attr->path_mig_state == IB_MIG_REARM) {
 671                         if (qp->s_mig_state == IB_MIG_ARMED)
 672                                 goto inval;
 673                         if (new_state != IB_QPS_RTS)
 674                                 goto inval;
 675                 } else if (attr->path_mig_state == IB_MIG_MIGRATED) {
 676                         if (qp->s_mig_state == IB_MIG_REARM)
 677                                 goto inval;
 678                         if (new_state != IB_QPS_RTS && new_state != IB_QPS_SQD)
 679                                 goto inval;
 680                         if (qp->s_mig_state == IB_MIG_ARMED)
 681                                 mig = 1;
 682                 } else
 683                         goto inval;
 684         }
 685
 686         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 687                 if (attr->max_dest_rd_atomic > QIB_MAX_RDMA_ATOMIC)
 688                         goto inval;
 689
 690         switch (new_state) {
 691         case IB_QPS_RESET:
 692                 if (qp->state != IB_QPS_RESET) {
 693                         qp->state = IB_QPS_RESET;
 694                         spin_lock(&dev->pending_lock);
 695                         if (!list_empty(&qp->iowait))
 696                                 list_del_init(&qp->iowait);
 697                         spin_unlock(&dev->pending_lock);
 698                         qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
 699                         spin_unlock(&qp->s_lock);
 700                         spin_unlock_irq(&qp->r_lock);
 701                         /* Stop the sending work queue and retry timer */
 702                         cancel_work_sync(&qp->s_work);
 703                         del_timer_sync(&qp->s_timer);
 704                         wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
 705                         if (qp->s_tx) {
 706                                 qib_put_txreq(qp->s_tx);
 707                                 qp->s_tx = NULL;
 708                         }
 709                         remove_qp(dev, qp);
 710                         wait_event(qp->wait, !atomic_read(&qp->refcount));
 711                         spin_lock_irq(&qp->r_lock);
 712                         spin_lock(&qp->s_lock);
 713                         clear_mr_refs(qp, 1);
 714                         qib_reset_qp(qp, ibqp->qp_type);
 715                 }
 716                 break;
 717
 718         case IB_QPS_RTR:
 719                 /* Allow event to retrigger if QP set to RTR more than once */
 720                 qp->r_flags &= ~QIB_R_COMM_EST;
 721                 qp->state = new_state;
 722                 break;
 723
 724         case IB_QPS_SQD:
 725                 qp->s_draining = qp->s_last != qp->s_cur;
 726                 qp->state = new_state;
 727                 break;
 728
 729         case IB_QPS_SQE:
 730                 if (qp->ibqp.qp_type == IB_QPT_RC)
 731                         goto inval;
 732                 qp->state = new_state;
 733                 break;
 734
 735         case IB_QPS_ERR:
 736                 lastwqe = qib_error_qp(qp, IB_WC_WR_FLUSH_ERR);
 737                 break;
 738
 739         default:
 740                 qp->state = new_state;
 741                 break;
 742         }
 743
 744         if (attr_mask & IB_QP_PKEY_INDEX)
 745                 qp->s_pkey_index = attr->pkey_index;
 746
 747         if (attr_mask & IB_QP_PORT)
 748                 qp->port_num = attr->port_num;
 749
 750         if (attr_mask & IB_QP_DEST_QPN)
 751                 qp->remote_qpn = attr->dest_qp_num;
 752
 753         if (attr_mask & IB_QP_SQ_PSN) {
 754                 qp->s_next_psn = attr->sq_psn & QIB_PSN_MASK;
 755                 qp->s_psn = qp->s_next_psn;
 756                 qp->s_sending_psn = qp->s_next_psn;
 757                 qp->s_last_psn = qp->s_next_psn - 1;
 758                 qp->s_sending_hpsn = qp->s_last_psn;
 759         }
 760
 761         if (attr_mask & IB_QP_RQ_PSN)
 762                 qp->r_psn = attr->rq_psn & QIB_PSN_MASK;
 763
 764         if (attr_mask & IB_QP_ACCESS_FLAGS)
 765                 qp->qp_access_flags = attr->qp_access_flags;
 766
 767         if (attr_mask & IB_QP_AV) {
 768                 qp->remote_ah_attr = attr->ah_attr;
 769                 qp->s_srate = attr->ah_attr.static_rate;
 770         }
 771
 772         if (attr_mask & IB_QP_ALT_PATH) {
 773                 qp->alt_ah_attr = attr->alt_ah_attr;
 774                 qp->s_alt_pkey_index = attr->alt_pkey_index;
 775         }
 776
 777         if (attr_mask & IB_QP_PATH_MIG_STATE) {
 778                 qp->s_mig_state = attr->path_mig_state;
 779                 if (mig) {
 780                         qp->remote_ah_attr = qp->alt_ah_attr;
 781                         qp->port_num = qp->alt_ah_attr.port_num;
 782                         qp->s_pkey_index = qp->s_alt_pkey_index;
 783                 }
 784         }
 785
 786         if (attr_mask & IB_QP_PATH_MTU) {
 787                 qp->path_mtu = pmtu;
 788                 qp->pmtu = ib_mtu_enum_to_int(pmtu);
 789         }
 790
 791         if (attr_mask & IB_QP_RETRY_CNT) {
 792                 qp->s_retry_cnt = attr->retry_cnt;
 793                 qp->s_retry = attr->retry_cnt;
 794         }
 795
 796         if (attr_mask & IB_QP_RNR_RETRY) {
 797                 qp->s_rnr_retry_cnt = attr->rnr_retry;
 798                 qp->s_rnr_retry = attr->rnr_retry;
 799         }
 800
 801         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 802                 qp->r_min_rnr_timer = attr->min_rnr_timer;
 803
 804         if (attr_mask & IB_QP_TIMEOUT) {
 805                 qp->timeout = attr->timeout;
 806                 qp->timeout_jiffies =
 807                         usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
 808                                 1000UL);
 809         }
 810
 811         if (attr_mask & IB_QP_QKEY)
 812                 qp->qkey = attr->qkey;
 813
 814         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 815                 qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
 816
 817         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
 818                 qp->s_max_rd_atomic = attr->max_rd_atomic;
 819
 820         spin_unlock(&qp->s_lock);
 821         spin_unlock_irq(&qp->r_lock);
 822
 823         if (cur_state == IB_QPS_RESET && new_state == IB_QPS_INIT)
 824                 insert_qp(dev, qp);
 825
 826         if (lastwqe) {
 827                 ev.device = qp->ibqp.device;
 828                 ev.element.qp = &qp->ibqp;
 829                 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 830                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 831         }
 832         if (mig) {
 833                 ev.device = qp->ibqp.device;
 834                 ev.element.qp = &qp->ibqp;
 835                 ev.event = IB_EVENT_PATH_MIG;
 836                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 837         }
 838         ret = 0;
 839         goto bail;
 840
 841 inval:
 842         spin_unlock(&qp->s_lock);
 843         spin_unlock_irq(&qp->r_lock);
 844         ret = -EINVAL;
 845
 846 bail:
 847         return ret;
 848 }
 849
 850 int qib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 851                  int attr_mask, struct ib_qp_init_attr *init_attr)
 852 {
 853         struct qib_qp *qp = to_iqp(ibqp);
 854
 855         attr->qp_state = qp->state;
 856         attr->cur_qp_state = attr->qp_state;
 857         attr->path_mtu = qp->path_mtu;
 858         attr->path_mig_state = qp->s_mig_state;
 859         attr->qkey = qp->qkey;
 860         attr->rq_psn = qp->r_psn & QIB_PSN_MASK;
 861         attr->sq_psn = qp->s_next_psn & QIB_PSN_MASK;
 862         attr->dest_qp_num = qp->remote_qpn;
 863         attr->qp_access_flags = qp->qp_access_flags;
 864         attr->cap.max_send_wr = qp->s_size - 1;
 865         attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
 866         attr->cap.max_send_sge = qp->s_max_sge;
 867         attr->cap.max_recv_sge = qp->r_rq.max_sge;
 868         attr->cap.max_inline_data = 0;
 869         attr->ah_attr = qp->remote_ah_attr;
 870         attr->alt_ah_attr = qp->alt_ah_attr;
 871         attr->pkey_index = qp->s_pkey_index;
 872         attr->alt_pkey_index = qp->s_alt_pkey_index;
 873         attr->en_sqd_async_notify = 0;
 874         attr->sq_draining = qp->s_draining;
 875         attr->max_rd_atomic = qp->s_max_rd_atomic;
 876         attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
 877         attr->min_rnr_timer = qp->r_min_rnr_timer;
 878         attr->port_num = qp->port_num;
 879         attr->timeout = qp->timeout;
 880         attr->retry_cnt = qp->s_retry_cnt;
 881         attr->rnr_retry = qp->s_rnr_retry_cnt;
 882         attr->alt_port_num = qp->alt_ah_attr.port_num;
 883         attr->alt_timeout = qp->alt_timeout;
 884
 885         init_attr->event_handler = qp->ibqp.event_handler;
 886         init_attr->qp_context = qp->ibqp.qp_context;
 887         init_attr->send_cq = qp->ibqp.send_cq;
 888         init_attr->recv_cq = qp->ibqp.recv_cq;
 889         init_attr->srq = qp->ibqp.srq;
 890         init_attr->cap = attr->cap;
 891         if (qp->s_flags & QIB_S_SIGNAL_REQ_WR)
 892                 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
 893         else
 894                 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
 895         init_attr->qp_type = qp->ibqp.qp_type;
 896         init_attr->port_num = qp->port_num;
 897         return 0;
 898 }
 899
 900 /**
 901  * qib_compute_aeth - compute the AETH (syndrome + MSN)
 902  * @qp: the queue pair to compute the AETH for
 903  *
 904  * Returns the AETH.
 905  */
 906 __be32 qib_compute_aeth(struct qib_qp *qp)
 907 {
 908         u32 aeth = qp->r_msn & QIB_MSN_MASK;
 909
 910         if (qp->ibqp.srq) {
 911                 /*
 912                  * Shared receive queues don't generate credits.
 913                  * Set the credit field to the invalid value.
 914                  */
 915                 aeth |= QIB_AETH_CREDIT_INVAL << QIB_AETH_CREDIT_SHIFT;
 916         } else {
 917                 u32 min, max, x;
 918                 u32 credits;
 919                 struct qib_rwq *wq = qp->r_rq.wq;
 920                 u32 head;
 921                 u32 tail;
 922
 923                 /* sanity check pointers before trusting them */
 924                 head = wq->head;
 925                 if (head >= qp->r_rq.size)
 926                         head = 0;
 927                 tail = wq->tail;
 928                 if (tail >= qp->r_rq.size)
 929                         tail = 0;
 930                 /*
 931                  * Compute the number of credits available (RWQEs).
 932                  * XXX Not holding the r_rq.lock here so there is a small
 933                  * chance that the pair of reads are not atomic.
 934                  */
 935                 credits = head - tail;
 936                 if ((int)credits < 0)
 937                         credits += qp->r_rq.size;
 938                 /*
 939                  * Binary search the credit table to find the code to
 940                  * use.
 941                  */
 942                 min = 0;
 943                 max = 31;
 944                 for (;;) {
 945                         x = (min + max) / 2;
 946                         if (credit_table[x] == credits)
 947                                 break;
 948                         if (credit_table[x] > credits)
 949                                 max = x;
 950                         else if (min == x)
 951                                 break;
 952                         else
 953                                 min = x;
 954                 }
 955                 aeth |= x << QIB_AETH_CREDIT_SHIFT;
 956         }
 957         return cpu_to_be32(aeth);
 958 }
 959
 960 /**
 961  * qib_create_qp - create a queue pair for a device
 962  * @ibpd: the protection domain who's device we create the queue pair for
 963  * @init_attr: the attributes of the queue pair
 964  * @udata: user data for libibverbs.so
 965  *
 966  * Returns the queue pair on success, otherwise returns an errno.
 967  *
 968  * Called by the ib_create_qp() core verbs function.
 969  */
 970 struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
 971                             struct ib_qp_init_attr *init_attr,
 972                             struct ib_udata *udata)
 973 {
 974         struct qib_qp *qp;
 975         int err;
 976         struct qib_swqe *swq = NULL;
 977         struct qib_ibdev *dev;
 978         struct qib_devdata *dd;
 979         size_t sz;
 980         size_t sg_list_sz;
 981         struct ib_qp *ret;
 982
 983         if (init_attr->cap.max_send_sge > ib_qib_max_sges ||
 984             init_attr->cap.max_send_wr > ib_qib_max_qp_wrs) {
 985                 ret = ERR_PTR(-EINVAL);
 986                 goto bail;
 987         }
 988
 989         /* Check receive queue parameters if no SRQ is specified. */
 990         if (!init_attr->srq) {
 991                 if (init_attr->cap.max_recv_sge > ib_qib_max_sges ||
 992                     init_attr->cap.max_recv_wr > ib_qib_max_qp_wrs) {
 993                         ret = ERR_PTR(-EINVAL);
 994                         goto bail;
 995                 }
 996                 if (init_attr->cap.max_send_sge +
 997                     init_attr->cap.max_send_wr +
 998                     init_attr->cap.max_recv_sge +
 999                     init_attr->cap.max_recv_wr == 0) {
1000                         ret = ERR_PTR(-EINVAL);
1001                         goto bail;
1002                 }
1003         }
1004
1005         switch (init_attr->qp_type) {
1006         case IB_QPT_SMI:
1007         case IB_QPT_GSI:
1008                 if (init_attr->port_num == 0 ||
1009                     init_attr->port_num > ibpd->device->phys_port_cnt) {
1010                         ret = ERR_PTR(-EINVAL);
1011                         goto bail;
1012                 }
1013         case IB_QPT_UC:
1014         case IB_QPT_RC:
1015         case IB_QPT_UD:
1016                 sz = sizeof(struct qib_sge) *
1017                         init_attr->cap.max_send_sge +
1018                         sizeof(struct qib_swqe);
1019                 swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
1020                 if (swq == NULL) {
1021                         ret = ERR_PTR(-ENOMEM);
1022                         goto bail;
1023                 }
1024                 sz = sizeof(*qp);
1025                 sg_list_sz = 0;
1026                 if (init_attr->srq) {
1027                         struct qib_srq *srq = to_isrq(init_attr->srq);
1028
1029                         if (srq->rq.max_sge > 1)
1030                                 sg_list_sz = sizeof(*qp->r_sg_list) *
1031                                         (srq->rq.max_sge - 1);
1032                 } else if (init_attr->cap.max_recv_sge > 1)
1033                         sg_list_sz = sizeof(*qp->r_sg_list) *
1034                                 (init_attr->cap.max_recv_sge - 1);
1035                 qp = kzalloc(sz + sg_list_sz, GFP_KERNEL);
1036                 if (!qp) {
1037                         ret = ERR_PTR(-ENOMEM);
1038                         goto bail_swq;
1039                 }
1040                 RCU_INIT_POINTER(qp->next, NULL);
1041                 qp->s_hdr = kzalloc(sizeof(*qp->s_hdr), GFP_KERNEL);
1042                 if (!qp->s_hdr) {
1043                         ret = ERR_PTR(-ENOMEM);
1044                         goto bail_qp;
1045                 }
1046                 qp->timeout_jiffies =
1047                         usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
1048                                 1000UL);
1049                 if (init_attr->srq)
1050                         sz = 0;
1051                 else {
1052                         qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
1053                         qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
1054                         sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
1055                                 sizeof(struct qib_rwqe);
1056                         qp->r_rq.wq = vmalloc_user(sizeof(struct qib_rwq) +
1057                                                    qp->r_rq.size * sz);
1058                         if (!qp->r_rq.wq) {
1059                                 ret = ERR_PTR(-ENOMEM);
1060                                 goto bail_qp;
1061                         }
1062                 }
1063
1064                 /*
1065                  * ib_create_qp() will initialize qp->ibqp
1066                  * except for qp->ibqp.qp_num.
1067                  */
1068                 spin_lock_init(&qp->r_lock);
1069                 spin_lock_init(&qp->s_lock);
1070                 spin_lock_init(&qp->r_rq.lock);
1071                 atomic_set(&qp->refcount, 0);
1072                 init_waitqueue_head(&qp->wait);
1073                 init_waitqueue_head(&qp->wait_dma);
1074                 init_timer(&qp->s_timer);
1075                 qp->s_timer.data = (unsigned long)qp;
1076                 INIT_WORK(&qp->s_work, qib_do_send);
1077                 INIT_LIST_HEAD(&qp->iowait);
1078                 INIT_LIST_HEAD(&qp->rspwait);
1079                 qp->state = IB_QPS_RESET;
1080                 qp->s_wq = swq;
1081                 qp->s_size = init_attr->cap.max_send_wr + 1;
1082                 qp->s_max_sge = init_attr->cap.max_send_sge;
1083                 if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
1084                         qp->s_flags = QIB_S_SIGNAL_REQ_WR;
1085                 dev = to_idev(ibpd->device);
1086                 dd = dd_from_dev(dev);
1087                 err = alloc_qpn(dd, &dev->qpn_table, init_attr->qp_type,
1088                                 init_attr->port_num);
1089                 if (err < 0) {
1090                         ret = ERR_PTR(err);
1091                         vfree(qp->r_rq.wq);
1092                         goto bail_qp;
1093                 }
1094                 qp->ibqp.qp_num = err;
1095                 qp->port_num = init_attr->port_num;
1096                 qib_reset_qp(qp, init_attr->qp_type);
1097                 break;
1098
1099         default:
1100                 /* Don't support raw QPs */
1101                 ret = ERR_PTR(-ENOSYS);
1102                 goto bail;
1103         }
1104
1105         init_attr->cap.max_inline_data = 0;
1106
1107         /*
1108          * Return the address of the RWQ as the offset to mmap.
1109          * See qib_mmap() for details.
1110          */
1111         if (udata && udata->outlen >= sizeof(__u64)) {
1112                 if (!qp->r_rq.wq) {
1113                         __u64 offset = 0;
1114
1115                         err = ib_copy_to_udata(udata, &offset,
1116                                                sizeof(offset));
1117                         if (err) {
1118                                 ret = ERR_PTR(err);
1119                                 goto bail_ip;
1120                         }
1121                 } else {
1122                         u32 s = sizeof(struct qib_rwq) + qp->r_rq.size * sz;
1123
1124                         qp->ip = qib_create_mmap_info(dev, s,
1125                                                       ibpd->uobject->context,
1126                                                       qp->r_rq.wq);
1127                         if (!qp->ip) {
1128                                 ret = ERR_PTR(-ENOMEM);
1129                                 goto bail_ip;
1130                         }
1131
1132                         err = ib_copy_to_udata(udata, &(qp->ip->offset),
1133                                                sizeof(qp->ip->offset));
1134                         if (err) {
1135                                 ret = ERR_PTR(err);
1136                                 goto bail_ip;
1137                         }
1138                 }
1139         }
1140
1141         spin_lock(&dev->n_qps_lock);
1142         if (dev->n_qps_allocated == ib_qib_max_qps) {
1143                 spin_unlock(&dev->n_qps_lock);
1144                 ret = ERR_PTR(-ENOMEM);
1145                 goto bail_ip;
1146         }
1147
1148         dev->n_qps_allocated++;
1149         spin_unlock(&dev->n_qps_lock);
1150
1151         if (qp->ip) {
1152                 spin_lock_irq(&dev->pending_lock);
1153                 list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
1154                 spin_unlock_irq(&dev->pending_lock);
1155         }
1156
1157         ret = &qp->ibqp;
1158         goto bail;
1159
1160 bail_ip:
1161         if (qp->ip)
1162                 kref_put(&qp->ip->ref, qib_release_mmap_info);
1163         else
1164                 vfree(qp->r_rq.wq);
1165         free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1166 bail_qp:
1167         kfree(qp->s_hdr);
1168         kfree(qp);
1169 bail_swq:
1170         vfree(swq);
1171 bail:
1172         return ret;
1173 }
1174
1175 /**
1176  * qib_destroy_qp - destroy a queue pair
1177  * @ibqp: the queue pair to destroy
1178  *
1179  * Returns 0 on success.
1180  *
1181  * Note that this can be called while the QP is actively sending or
1182  * receiving!
1183  */
1184 int qib_destroy_qp(struct ib_qp *ibqp)
1185 {
1186         struct qib_qp *qp = to_iqp(ibqp);
1187         struct qib_ibdev *dev = to_idev(ibqp->device);
1188
1189         /* Make sure HW and driver activity is stopped. */
1190         spin_lock_irq(&qp->s_lock);
1191         if (qp->state != IB_QPS_RESET) {
1192                 qp->state = IB_QPS_RESET;
1193                 spin_lock(&dev->pending_lock);
1194                 if (!list_empty(&qp->iowait))
1195                         list_del_init(&qp->iowait);
1196                 spin_unlock(&dev->pending_lock);
1197                 qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
1198                 spin_unlock_irq(&qp->s_lock);
1199                 cancel_work_sync(&qp->s_work);
1200                 del_timer_sync(&qp->s_timer);
1201                 wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
1202                 if (qp->s_tx) {
1203                         qib_put_txreq(qp->s_tx);
1204                         qp->s_tx = NULL;
1205                 }
1206                 remove_qp(dev, qp);
1207                 wait_event(qp->wait, !atomic_read(&qp->refcount));
1208                 clear_mr_refs(qp, 1);
1209         } else
1210                 spin_unlock_irq(&qp->s_lock);
1211
1212         /* all user's cleaned up, mark it available */
1213         free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1214         spin_lock(&dev->n_qps_lock);
1215         dev->n_qps_allocated--;
1216         spin_unlock(&dev->n_qps_lock);
1217
1218         if (qp->ip)
1219                 kref_put(&qp->ip->ref, qib_release_mmap_info);
1220         else
1221                 vfree(qp->r_rq.wq);
1222         vfree(qp->s_wq);
1223         kfree(qp->s_hdr);
1224         kfree(qp);
1225         return 0;
1226 }
1227
1228 /**
1229  * qib_init_qpn_table - initialize the QP number table for a device
1230  * @qpt: the QPN table
1231  */
1232 void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt)
1233 {
1234         spin_lock_init(&qpt->lock);
1235         qpt->last = 1;          /* start with QPN 2 */
1236         qpt->nmaps = 1;
1237         qpt->mask = dd->qpn_mask;
1238 }
1239
1240 /**
1241  * qib_free_qpn_table - free the QP number table for a device
1242  * @qpt: the QPN table
1243  */
1244 void qib_free_qpn_table(struct qib_qpn_table *qpt)
1245 {
1246         int i;
1247
1248         for (i = 0; i < ARRAY_SIZE(qpt->map); i++)
1249                 if (qpt->map[i].page)
1250                         free_page((unsigned long) qpt->map[i].page);
1251 }
1252
1253 /**
1254  * qib_get_credit - flush the send work queue of a QP
1255  * @qp: the qp who's send work queue to flush
1256  * @aeth: the Acknowledge Extended Transport Header
1257  *
1258  * The QP s_lock should be held.
1259  */
1260 void qib_get_credit(struct qib_qp *qp, u32 aeth)
1261 {
1262         u32 credit = (aeth >> QIB_AETH_CREDIT_SHIFT) & QIB_AETH_CREDIT_MASK;
1263
1264         /*
1265          * If the credit is invalid, we can send
1266          * as many packets as we like.  Otherwise, we have to
1267          * honor the credit field.
1268          */
1269         if (credit == QIB_AETH_CREDIT_INVAL) {
1270                 if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1271                         qp->s_flags |= QIB_S_UNLIMITED_CREDIT;
1272                         if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1273                                 qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1274                                 qib_schedule_send(qp);
1275                         }
1276                 }
1277         } else if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1278                 /* Compute new LSN (i.e., MSN + credit) */
1279                 credit = (aeth + credit_table[credit]) & QIB_MSN_MASK;
1280                 if (qib_cmp24(credit, qp->s_lsn) > 0) {
1281                         qp->s_lsn = credit;
1282                         if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1283                                 qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1284                                 qib_schedule_send(qp);
1285                         }
1286                 }
1287         }
1288 }