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                 qib_put_ss(&qp->s_rdma_read_sge);
 410
 411         qib_put_ss(&qp->r_sge);
 412
 413         if (clr_sends) {
 414                 while (qp->s_last != qp->s_head) {
 415                         struct qib_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
 416                         unsigned i;
 417
 418                         for (i = 0; i < wqe->wr.num_sge; i++) {
 419                                 struct qib_sge *sge = &wqe->sg_list[i];
 420
 421                                 qib_put_mr(sge->mr);
 422                         }
 423                         if (qp->ibqp.qp_type == IB_QPT_UD ||
 424                             qp->ibqp.qp_type == IB_QPT_SMI ||
 425                             qp->ibqp.qp_type == IB_QPT_GSI)
 426                                 atomic_dec(&to_iah(wqe->wr.wr.ud.ah)->refcount);
 427                         if (++qp->s_last >= qp->s_size)
 428                                 qp->s_last = 0;
 429                 }
 430                 if (qp->s_rdma_mr) {
 431                         qib_put_mr(qp->s_rdma_mr);
 432                         qp->s_rdma_mr = NULL;
 433                 }
 434         }
 435
 436         if (qp->ibqp.qp_type != IB_QPT_RC)
 437                 return;
 438
 439         for (n = 0; n < ARRAY_SIZE(qp->s_ack_queue); n++) {
 440                 struct qib_ack_entry *e = &qp->s_ack_queue[n];
 441
 442                 if (e->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST &&
 443                     e->rdma_sge.mr) {
 444                         qib_put_mr(e->rdma_sge.mr);
 445                         e->rdma_sge.mr = NULL;
 446                 }
 447         }
 448 }
 449
 450 /**
 451  * qib_error_qp - put a QP into the error state
 452  * @qp: the QP to put into the error state
 453  * @err: the receive completion error to signal if a RWQE is active
 454  *
 455  * Flushes both send and receive work queues.
 456  * Returns true if last WQE event should be generated.
 457  * The QP r_lock and s_lock should be held and interrupts disabled.
 458  * If we are already in error state, just return.
 459  */
 460 int qib_error_qp(struct qib_qp *qp, enum ib_wc_status err)
 461 {
 462         struct qib_ibdev *dev = to_idev(qp->ibqp.device);
 463         struct ib_wc wc;
 464         int ret = 0;
 465
 466         if (qp->state == IB_QPS_ERR || qp->state == IB_QPS_RESET)
 467                 goto bail;
 468
 469         qp->state = IB_QPS_ERR;
 470
 471         if (qp->s_flags & (QIB_S_TIMER | QIB_S_WAIT_RNR)) {
 472                 qp->s_flags &= ~(QIB_S_TIMER | QIB_S_WAIT_RNR);
 473                 del_timer(&qp->s_timer);
 474         }
 475
 476         if (qp->s_flags & QIB_S_ANY_WAIT_SEND)
 477                 qp->s_flags &= ~QIB_S_ANY_WAIT_SEND;
 478
 479         spin_lock(&dev->pending_lock);
 480         if (!list_empty(&qp->iowait) && !(qp->s_flags & QIB_S_BUSY)) {
 481                 qp->s_flags &= ~QIB_S_ANY_WAIT_IO;
 482                 list_del_init(&qp->iowait);
 483         }
 484         spin_unlock(&dev->pending_lock);
 485
 486         if (!(qp->s_flags & QIB_S_BUSY)) {
 487                 qp->s_hdrwords = 0;
 488                 if (qp->s_rdma_mr) {
 489                         qib_put_mr(qp->s_rdma_mr);
 490                         qp->s_rdma_mr = NULL;
 491                 }
 492                 if (qp->s_tx) {
 493                         qib_put_txreq(qp->s_tx);
 494                         qp->s_tx = NULL;
 495                 }
 496         }
 497
 498         /* Schedule the sending tasklet to drain the send work queue. */
 499         if (qp->s_last != qp->s_head)
 500                 qib_schedule_send(qp);
 501
 502         clear_mr_refs(qp, 0);
 503
 504         memset(&wc, 0, sizeof(wc));
 505         wc.qp = &qp->ibqp;
 506         wc.opcode = IB_WC_RECV;
 507
 508         if (test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags)) {
 509                 wc.wr_id = qp->r_wr_id;
 510                 wc.status = err;
 511                 qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 512         }
 513         wc.status = IB_WC_WR_FLUSH_ERR;
 514
 515         if (qp->r_rq.wq) {
 516                 struct qib_rwq *wq;
 517                 u32 head;
 518                 u32 tail;
 519
 520                 spin_lock(&qp->r_rq.lock);
 521
 522                 /* sanity check pointers before trusting them */
 523                 wq = qp->r_rq.wq;
 524                 head = wq->head;
 525                 if (head >= qp->r_rq.size)
 526                         head = 0;
 527                 tail = wq->tail;
 528                 if (tail >= qp->r_rq.size)
 529                         tail = 0;
 530                 while (tail != head) {
 531                         wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
 532                         if (++tail >= qp->r_rq.size)
 533                                 tail = 0;
 534                         qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 535                 }
 536                 wq->tail = tail;
 537
 538                 spin_unlock(&qp->r_rq.lock);
 539         } else if (qp->ibqp.event_handler)
 540                 ret = 1;
 541
 542 bail:
 543         return ret;
 544 }
 545
 546 /**
 547  * qib_modify_qp - modify the attributes of a queue pair
 548  * @ibqp: the queue pair who's attributes we're modifying
 549  * @attr: the new attributes
 550  * @attr_mask: the mask of attributes to modify
 551  * @udata: user data for libibverbs.so
 552  *
 553  * Returns 0 on success, otherwise returns an errno.
 554  */
 555 int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 556                   int attr_mask, struct ib_udata *udata)
 557 {
 558         struct qib_ibdev *dev = to_idev(ibqp->device);
 559         struct qib_qp *qp = to_iqp(ibqp);
 560         enum ib_qp_state cur_state, new_state;
 561         struct ib_event ev;
 562         int lastwqe = 0;
 563         int mig = 0;
 564         int ret;
 565         u32 pmtu = 0; /* for gcc warning only */
 566
 567         spin_lock_irq(&qp->r_lock);
 568         spin_lock(&qp->s_lock);
 569
 570         cur_state = attr_mask & IB_QP_CUR_STATE ?
 571                 attr->cur_qp_state : qp->state;
 572         new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
 573
 574         if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
 575                                 attr_mask))
 576                 goto inval;
 577
 578         if (attr_mask & IB_QP_AV) {
 579                 if (attr->ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
 580                         goto inval;
 581                 if (qib_check_ah(qp->ibqp.device, &attr->ah_attr))
 582                         goto inval;
 583         }
 584
 585         if (attr_mask & IB_QP_ALT_PATH) {
 586                 if (attr->alt_ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
 587                         goto inval;
 588                 if (qib_check_ah(qp->ibqp.device, &attr->alt_ah_attr))
 589                         goto inval;
 590                 if (attr->alt_pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
 591                         goto inval;
 592         }
 593
 594         if (attr_mask & IB_QP_PKEY_INDEX)
 595                 if (attr->pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
 596                         goto inval;
 597
 598         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 599                 if (attr->min_rnr_timer > 31)
 600                         goto inval;
 601
 602         if (attr_mask & IB_QP_PORT)
 603                 if (qp->ibqp.qp_type == IB_QPT_SMI ||
 604                     qp->ibqp.qp_type == IB_QPT_GSI ||
 605                     attr->port_num == 0 ||
 606                     attr->port_num > ibqp->device->phys_port_cnt)
 607                         goto inval;
 608
 609         if (attr_mask & IB_QP_DEST_QPN)
 610                 if (attr->dest_qp_num > QIB_QPN_MASK)
 611                         goto inval;
 612
 613         if (attr_mask & IB_QP_RETRY_CNT)
 614                 if (attr->retry_cnt > 7)
 615                         goto inval;
 616
 617         if (attr_mask & IB_QP_RNR_RETRY)
 618                 if (attr->rnr_retry > 7)
 619                         goto inval;
 620
 621         /*
 622          * Don't allow invalid path_mtu values.  OK to set greater
 623          * than the active mtu (or even the max_cap, if we have tuned
 624          * that to a small mtu.  We'll set qp->path_mtu
 625          * to the lesser of requested attribute mtu and active,
 626          * for packetizing messages.
 627          * Note that the QP port has to be set in INIT and MTU in RTR.
 628          */
 629         if (attr_mask & IB_QP_PATH_MTU) {
 630                 struct qib_devdata *dd = dd_from_dev(dev);
 631                 int mtu, pidx = qp->port_num - 1;
 632
 633                 mtu = ib_mtu_enum_to_int(attr->path_mtu);
 634                 if (mtu == -1)
 635                         goto inval;
 636                 if (mtu > dd->pport[pidx].ibmtu) {
 637                         switch (dd->pport[pidx].ibmtu) {
 638                         case 4096:
 639                                 pmtu = IB_MTU_4096;
 640                                 break;
 641                         case 2048:
 642                                 pmtu = IB_MTU_2048;
 643                                 break;
 644                         case 1024:
 645                                 pmtu = IB_MTU_1024;
 646                                 break;
 647                         case 512:
 648                                 pmtu = IB_MTU_512;
 649                                 break;
 650                         case 256:
 651                                 pmtu = IB_MTU_256;
 652                                 break;
 653                         default:
 654                                 pmtu = IB_MTU_2048;
 655                         }
 656                 } else
 657                         pmtu = attr->path_mtu;
 658         }
 659
 660         if (attr_mask & IB_QP_PATH_MIG_STATE) {
 661                 if (attr->path_mig_state == IB_MIG_REARM) {
 662                         if (qp->s_mig_state == IB_MIG_ARMED)
 663                                 goto inval;
 664                         if (new_state != IB_QPS_RTS)
 665                                 goto inval;
 666                 } else if (attr->path_mig_state == IB_MIG_MIGRATED) {
 667                         if (qp->s_mig_state == IB_MIG_REARM)
 668                                 goto inval;
 669                         if (new_state != IB_QPS_RTS && new_state != IB_QPS_SQD)
 670                                 goto inval;
 671                         if (qp->s_mig_state == IB_MIG_ARMED)
 672                                 mig = 1;
 673                 } else
 674                         goto inval;
 675         }
 676
 677         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 678                 if (attr->max_dest_rd_atomic > QIB_MAX_RDMA_ATOMIC)
 679                         goto inval;
 680
 681         switch (new_state) {
 682         case IB_QPS_RESET:
 683                 if (qp->state != IB_QPS_RESET) {
 684                         qp->state = IB_QPS_RESET;
 685                         spin_lock(&dev->pending_lock);
 686                         if (!list_empty(&qp->iowait))
 687                                 list_del_init(&qp->iowait);
 688                         spin_unlock(&dev->pending_lock);
 689                         qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
 690                         spin_unlock(&qp->s_lock);
 691                         spin_unlock_irq(&qp->r_lock);
 692                         /* Stop the sending work queue and retry timer */
 693                         cancel_work_sync(&qp->s_work);
 694                         del_timer_sync(&qp->s_timer);
 695                         wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
 696                         if (qp->s_tx) {
 697                                 qib_put_txreq(qp->s_tx);
 698                                 qp->s_tx = NULL;
 699                         }
 700                         remove_qp(dev, qp);
 701                         wait_event(qp->wait, !atomic_read(&qp->refcount));
 702                         spin_lock_irq(&qp->r_lock);
 703                         spin_lock(&qp->s_lock);
 704                         clear_mr_refs(qp, 1);
 705                         qib_reset_qp(qp, ibqp->qp_type);
 706                 }
 707                 break;
 708
 709         case IB_QPS_RTR:
 710                 /* Allow event to retrigger if QP set to RTR more than once */
 711                 qp->r_flags &= ~QIB_R_COMM_EST;
 712                 qp->state = new_state;
 713                 break;
 714
 715         case IB_QPS_SQD:
 716                 qp->s_draining = qp->s_last != qp->s_cur;
 717                 qp->state = new_state;
 718                 break;
 719
 720         case IB_QPS_SQE:
 721                 if (qp->ibqp.qp_type == IB_QPT_RC)
 722                         goto inval;
 723                 qp->state = new_state;
 724                 break;
 725
 726         case IB_QPS_ERR:
 727                 lastwqe = qib_error_qp(qp, IB_WC_WR_FLUSH_ERR);
 728                 break;
 729
 730         default:
 731                 qp->state = new_state;
 732                 break;
 733         }
 734
 735         if (attr_mask & IB_QP_PKEY_INDEX)
 736                 qp->s_pkey_index = attr->pkey_index;
 737
 738         if (attr_mask & IB_QP_PORT)
 739                 qp->port_num = attr->port_num;
 740
 741         if (attr_mask & IB_QP_DEST_QPN)
 742                 qp->remote_qpn = attr->dest_qp_num;
 743
 744         if (attr_mask & IB_QP_SQ_PSN) {
 745                 qp->s_next_psn = attr->sq_psn & QIB_PSN_MASK;
 746                 qp->s_psn = qp->s_next_psn;
 747                 qp->s_sending_psn = qp->s_next_psn;
 748                 qp->s_last_psn = qp->s_next_psn - 1;
 749                 qp->s_sending_hpsn = qp->s_last_psn;
 750         }
 751
 752         if (attr_mask & IB_QP_RQ_PSN)
 753                 qp->r_psn = attr->rq_psn & QIB_PSN_MASK;
 754
 755         if (attr_mask & IB_QP_ACCESS_FLAGS)
 756                 qp->qp_access_flags = attr->qp_access_flags;
 757
 758         if (attr_mask & IB_QP_AV) {
 759                 qp->remote_ah_attr = attr->ah_attr;
 760                 qp->s_srate = attr->ah_attr.static_rate;
 761         }
 762
 763         if (attr_mask & IB_QP_ALT_PATH) {
 764                 qp->alt_ah_attr = attr->alt_ah_attr;
 765                 qp->s_alt_pkey_index = attr->alt_pkey_index;
 766         }
 767
 768         if (attr_mask & IB_QP_PATH_MIG_STATE) {
 769                 qp->s_mig_state = attr->path_mig_state;
 770                 if (mig) {
 771                         qp->remote_ah_attr = qp->alt_ah_attr;
 772                         qp->port_num = qp->alt_ah_attr.port_num;
 773                         qp->s_pkey_index = qp->s_alt_pkey_index;
 774                 }
 775         }
 776
 777         if (attr_mask & IB_QP_PATH_MTU) {
 778                 qp->path_mtu = pmtu;
 779                 qp->pmtu = ib_mtu_enum_to_int(pmtu);
 780         }
 781
 782         if (attr_mask & IB_QP_RETRY_CNT) {
 783                 qp->s_retry_cnt = attr->retry_cnt;
 784                 qp->s_retry = attr->retry_cnt;
 785         }
 786
 787         if (attr_mask & IB_QP_RNR_RETRY) {
 788                 qp->s_rnr_retry_cnt = attr->rnr_retry;
 789                 qp->s_rnr_retry = attr->rnr_retry;
 790         }
 791
 792         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 793                 qp->r_min_rnr_timer = attr->min_rnr_timer;
 794
 795         if (attr_mask & IB_QP_TIMEOUT) {
 796                 qp->timeout = attr->timeout;
 797                 qp->timeout_jiffies =
 798                         usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
 799                                 1000UL);
 800         }
 801
 802         if (attr_mask & IB_QP_QKEY)
 803                 qp->qkey = attr->qkey;
 804
 805         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 806                 qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
 807
 808         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
 809                 qp->s_max_rd_atomic = attr->max_rd_atomic;
 810
 811         spin_unlock(&qp->s_lock);
 812         spin_unlock_irq(&qp->r_lock);
 813
 814         if (cur_state == IB_QPS_RESET && new_state == IB_QPS_INIT)
 815                 insert_qp(dev, qp);
 816
 817         if (lastwqe) {
 818                 ev.device = qp->ibqp.device;
 819                 ev.element.qp = &qp->ibqp;
 820                 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 821                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 822         }
 823         if (mig) {
 824                 ev.device = qp->ibqp.device;
 825                 ev.element.qp = &qp->ibqp;
 826                 ev.event = IB_EVENT_PATH_MIG;
 827                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 828         }
 829         ret = 0;
 830         goto bail;
 831
 832 inval:
 833         spin_unlock(&qp->s_lock);
 834         spin_unlock_irq(&qp->r_lock);
 835         ret = -EINVAL;
 836
 837 bail:
 838         return ret;
 839 }
 840
 841 int qib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 842                  int attr_mask, struct ib_qp_init_attr *init_attr)
 843 {
 844         struct qib_qp *qp = to_iqp(ibqp);
 845
 846         attr->qp_state = qp->state;
 847         attr->cur_qp_state = attr->qp_state;
 848         attr->path_mtu = qp->path_mtu;
 849         attr->path_mig_state = qp->s_mig_state;
 850         attr->qkey = qp->qkey;
 851         attr->rq_psn = qp->r_psn & QIB_PSN_MASK;
 852         attr->sq_psn = qp->s_next_psn & QIB_PSN_MASK;
 853         attr->dest_qp_num = qp->remote_qpn;
 854         attr->qp_access_flags = qp->qp_access_flags;
 855         attr->cap.max_send_wr = qp->s_size - 1;
 856         attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
 857         attr->cap.max_send_sge = qp->s_max_sge;
 858         attr->cap.max_recv_sge = qp->r_rq.max_sge;
 859         attr->cap.max_inline_data = 0;
 860         attr->ah_attr = qp->remote_ah_attr;
 861         attr->alt_ah_attr = qp->alt_ah_attr;
 862         attr->pkey_index = qp->s_pkey_index;
 863         attr->alt_pkey_index = qp->s_alt_pkey_index;
 864         attr->en_sqd_async_notify = 0;
 865         attr->sq_draining = qp->s_draining;
 866         attr->max_rd_atomic = qp->s_max_rd_atomic;
 867         attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
 868         attr->min_rnr_timer = qp->r_min_rnr_timer;
 869         attr->port_num = qp->port_num;
 870         attr->timeout = qp->timeout;
 871         attr->retry_cnt = qp->s_retry_cnt;
 872         attr->rnr_retry = qp->s_rnr_retry_cnt;
 873         attr->alt_port_num = qp->alt_ah_attr.port_num;
 874         attr->alt_timeout = qp->alt_timeout;
 875
 876         init_attr->event_handler = qp->ibqp.event_handler;
 877         init_attr->qp_context = qp->ibqp.qp_context;
 878         init_attr->send_cq = qp->ibqp.send_cq;
 879         init_attr->recv_cq = qp->ibqp.recv_cq;
 880         init_attr->srq = qp->ibqp.srq;
 881         init_attr->cap = attr->cap;
 882         if (qp->s_flags & QIB_S_SIGNAL_REQ_WR)
 883                 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
 884         else
 885                 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
 886         init_attr->qp_type = qp->ibqp.qp_type;
 887         init_attr->port_num = qp->port_num;
 888         return 0;
 889 }
 890
 891 /**
 892  * qib_compute_aeth - compute the AETH (syndrome + MSN)
 893  * @qp: the queue pair to compute the AETH for
 894  *
 895  * Returns the AETH.
 896  */
 897 __be32 qib_compute_aeth(struct qib_qp *qp)
 898 {
 899         u32 aeth = qp->r_msn & QIB_MSN_MASK;
 900
 901         if (qp->ibqp.srq) {
 902                 /*
 903                  * Shared receive queues don't generate credits.
 904                  * Set the credit field to the invalid value.
 905                  */
 906                 aeth |= QIB_AETH_CREDIT_INVAL << QIB_AETH_CREDIT_SHIFT;
 907         } else {
 908                 u32 min, max, x;
 909                 u32 credits;
 910                 struct qib_rwq *wq = qp->r_rq.wq;
 911                 u32 head;
 912                 u32 tail;
 913
 914                 /* sanity check pointers before trusting them */
 915                 head = wq->head;
 916                 if (head >= qp->r_rq.size)
 917                         head = 0;
 918                 tail = wq->tail;
 919                 if (tail >= qp->r_rq.size)
 920                         tail = 0;
 921                 /*
 922                  * Compute the number of credits available (RWQEs).
 923                  * XXX Not holding the r_rq.lock here so there is a small
 924                  * chance that the pair of reads are not atomic.
 925                  */
 926                 credits = head - tail;
 927                 if ((int)credits < 0)
 928                         credits += qp->r_rq.size;
 929                 /*
 930                  * Binary search the credit table to find the code to
 931                  * use.
 932                  */
 933                 min = 0;
 934                 max = 31;
 935                 for (;;) {
 936                         x = (min + max) / 2;
 937                         if (credit_table[x] == credits)
 938                                 break;
 939                         if (credit_table[x] > credits)
 940                                 max = x;
 941                         else if (min == x)
 942                                 break;
 943                         else
 944                                 min = x;
 945                 }
 946                 aeth |= x << QIB_AETH_CREDIT_SHIFT;
 947         }
 948         return cpu_to_be32(aeth);
 949 }
 950
 951 /**
 952  * qib_create_qp - create a queue pair for a device
 953  * @ibpd: the protection domain who's device we create the queue pair for
 954  * @init_attr: the attributes of the queue pair
 955  * @udata: user data for libibverbs.so
 956  *
 957  * Returns the queue pair on success, otherwise returns an errno.
 958  *
 959  * Called by the ib_create_qp() core verbs function.
 960  */
 961 struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
 962                             struct ib_qp_init_attr *init_attr,
 963                             struct ib_udata *udata)
 964 {
 965         struct qib_qp *qp;
 966         int err;
 967         struct qib_swqe *swq = NULL;
 968         struct qib_ibdev *dev;
 969         struct qib_devdata *dd;
 970         size_t sz;
 971         size_t sg_list_sz;
 972         struct ib_qp *ret;
 973
 974         if (init_attr->cap.max_send_sge > ib_qib_max_sges ||
 975             init_attr->cap.max_send_wr > ib_qib_max_qp_wrs) {
 976                 ret = ERR_PTR(-EINVAL);
 977                 goto bail;
 978         }
 979
 980         /* Check receive queue parameters if no SRQ is specified. */
 981         if (!init_attr->srq) {
 982                 if (init_attr->cap.max_recv_sge > ib_qib_max_sges ||
 983                     init_attr->cap.max_recv_wr > ib_qib_max_qp_wrs) {
 984                         ret = ERR_PTR(-EINVAL);
 985                         goto bail;
 986                 }
 987                 if (init_attr->cap.max_send_sge +
 988                     init_attr->cap.max_send_wr +
 989                     init_attr->cap.max_recv_sge +
 990                     init_attr->cap.max_recv_wr == 0) {
 991                         ret = ERR_PTR(-EINVAL);
 992                         goto bail;
 993                 }
 994         }
 995
 996         switch (init_attr->qp_type) {
 997         case IB_QPT_SMI:
 998         case IB_QPT_GSI:
 999                 if (init_attr->port_num == 0 ||
1000                     init_attr->port_num > ibpd->device->phys_port_cnt) {
1001                         ret = ERR_PTR(-EINVAL);
1002                         goto bail;
1003                 }
1004         case IB_QPT_UC:
1005         case IB_QPT_RC:
1006         case IB_QPT_UD:
1007                 sz = sizeof(struct qib_sge) *
1008                         init_attr->cap.max_send_sge +
1009                         sizeof(struct qib_swqe);
1010                 swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
1011                 if (swq == NULL) {
1012                         ret = ERR_PTR(-ENOMEM);
1013                         goto bail;
1014                 }
1015                 sz = sizeof(*qp);
1016                 sg_list_sz = 0;
1017                 if (init_attr->srq) {
1018                         struct qib_srq *srq = to_isrq(init_attr->srq);
1019
1020                         if (srq->rq.max_sge > 1)
1021                                 sg_list_sz = sizeof(*qp->r_sg_list) *
1022                                         (srq->rq.max_sge - 1);
1023                 } else if (init_attr->cap.max_recv_sge > 1)
1024                         sg_list_sz = sizeof(*qp->r_sg_list) *
1025                                 (init_attr->cap.max_recv_sge - 1);
1026                 qp = kzalloc(sz + sg_list_sz, GFP_KERNEL);
1027                 if (!qp) {
1028                         ret = ERR_PTR(-ENOMEM);
1029                         goto bail_swq;
1030                 }
1031                 RCU_INIT_POINTER(qp->next, NULL);
1032                 qp->s_hdr = kzalloc(sizeof(*qp->s_hdr), GFP_KERNEL);
1033                 if (!qp->s_hdr) {
1034                         ret = ERR_PTR(-ENOMEM);
1035                         goto bail_qp;
1036                 }
1037                 qp->timeout_jiffies =
1038                         usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
1039                                 1000UL);
1040                 if (init_attr->srq)
1041                         sz = 0;
1042                 else {
1043                         qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
1044                         qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
1045                         sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
1046                                 sizeof(struct qib_rwqe);
1047                         qp->r_rq.wq = vmalloc_user(sizeof(struct qib_rwq) +
1048                                                    qp->r_rq.size * sz);
1049                         if (!qp->r_rq.wq) {
1050                                 ret = ERR_PTR(-ENOMEM);
1051                                 goto bail_qp;
1052                         }
1053                 }
1054
1055                 /*
1056                  * ib_create_qp() will initialize qp->ibqp
1057                  * except for qp->ibqp.qp_num.
1058                  */
1059                 spin_lock_init(&qp->r_lock);
1060                 spin_lock_init(&qp->s_lock);
1061                 spin_lock_init(&qp->r_rq.lock);
1062                 atomic_set(&qp->refcount, 0);
1063                 init_waitqueue_head(&qp->wait);
1064                 init_waitqueue_head(&qp->wait_dma);
1065                 init_timer(&qp->s_timer);
1066                 qp->s_timer.data = (unsigned long)qp;
1067                 INIT_WORK(&qp->s_work, qib_do_send);
1068                 INIT_LIST_HEAD(&qp->iowait);
1069                 INIT_LIST_HEAD(&qp->rspwait);
1070                 qp->state = IB_QPS_RESET;
1071                 qp->s_wq = swq;
1072                 qp->s_size = init_attr->cap.max_send_wr + 1;
1073                 qp->s_max_sge = init_attr->cap.max_send_sge;
1074                 if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
1075                         qp->s_flags = QIB_S_SIGNAL_REQ_WR;
1076                 dev = to_idev(ibpd->device);
1077                 dd = dd_from_dev(dev);
1078                 err = alloc_qpn(dd, &dev->qpn_table, init_attr->qp_type,
1079                                 init_attr->port_num);
1080                 if (err < 0) {
1081                         ret = ERR_PTR(err);
1082                         vfree(qp->r_rq.wq);
1083                         goto bail_qp;
1084                 }
1085                 qp->ibqp.qp_num = err;
1086                 qp->port_num = init_attr->port_num;
1087                 qib_reset_qp(qp, init_attr->qp_type);
1088                 break;
1089
1090         default:
1091                 /* Don't support raw QPs */
1092                 ret = ERR_PTR(-ENOSYS);
1093                 goto bail;
1094         }
1095
1096         init_attr->cap.max_inline_data = 0;
1097
1098         /*
1099          * Return the address of the RWQ as the offset to mmap.
1100          * See qib_mmap() for details.
1101          */
1102         if (udata && udata->outlen >= sizeof(__u64)) {
1103                 if (!qp->r_rq.wq) {
1104                         __u64 offset = 0;
1105
1106                         err = ib_copy_to_udata(udata, &offset,
1107                                                sizeof(offset));
1108                         if (err) {
1109                                 ret = ERR_PTR(err);
1110                                 goto bail_ip;
1111                         }
1112                 } else {
1113                         u32 s = sizeof(struct qib_rwq) + qp->r_rq.size * sz;
1114
1115                         qp->ip = qib_create_mmap_info(dev, s,
1116                                                       ibpd->uobject->context,
1117                                                       qp->r_rq.wq);
1118                         if (!qp->ip) {
1119                                 ret = ERR_PTR(-ENOMEM);
1120                                 goto bail_ip;
1121                         }
1122
1123                         err = ib_copy_to_udata(udata, &(qp->ip->offset),
1124                                                sizeof(qp->ip->offset));
1125                         if (err) {
1126                                 ret = ERR_PTR(err);
1127                                 goto bail_ip;
1128                         }
1129                 }
1130         }
1131
1132         spin_lock(&dev->n_qps_lock);
1133         if (dev->n_qps_allocated == ib_qib_max_qps) {
1134                 spin_unlock(&dev->n_qps_lock);
1135                 ret = ERR_PTR(-ENOMEM);
1136                 goto bail_ip;
1137         }
1138
1139         dev->n_qps_allocated++;
1140         spin_unlock(&dev->n_qps_lock);
1141
1142         if (qp->ip) {
1143                 spin_lock_irq(&dev->pending_lock);
1144                 list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
1145                 spin_unlock_irq(&dev->pending_lock);
1146         }
1147
1148         ret = &qp->ibqp;
1149         goto bail;
1150
1151 bail_ip:
1152         if (qp->ip)
1153                 kref_put(&qp->ip->ref, qib_release_mmap_info);
1154         else
1155                 vfree(qp->r_rq.wq);
1156         free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1157 bail_qp:
1158         kfree(qp->s_hdr);
1159         kfree(qp);
1160 bail_swq:
1161         vfree(swq);
1162 bail:
1163         return ret;
1164 }
1165
1166 /**
1167  * qib_destroy_qp - destroy a queue pair
1168  * @ibqp: the queue pair to destroy
1169  *
1170  * Returns 0 on success.
1171  *
1172  * Note that this can be called while the QP is actively sending or
1173  * receiving!
1174  */
1175 int qib_destroy_qp(struct ib_qp *ibqp)
1176 {
1177         struct qib_qp *qp = to_iqp(ibqp);
1178         struct qib_ibdev *dev = to_idev(ibqp->device);
1179
1180         /* Make sure HW and driver activity is stopped. */
1181         spin_lock_irq(&qp->s_lock);
1182         if (qp->state != IB_QPS_RESET) {
1183                 qp->state = IB_QPS_RESET;
1184                 spin_lock(&dev->pending_lock);
1185                 if (!list_empty(&qp->iowait))
1186                         list_del_init(&qp->iowait);
1187                 spin_unlock(&dev->pending_lock);
1188                 qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
1189                 spin_unlock_irq(&qp->s_lock);
1190                 cancel_work_sync(&qp->s_work);
1191                 del_timer_sync(&qp->s_timer);
1192                 wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
1193                 if (qp->s_tx) {
1194                         qib_put_txreq(qp->s_tx);
1195                         qp->s_tx = NULL;
1196                 }
1197                 remove_qp(dev, qp);
1198                 wait_event(qp->wait, !atomic_read(&qp->refcount));
1199                 clear_mr_refs(qp, 1);
1200         } else
1201                 spin_unlock_irq(&qp->s_lock);
1202
1203         /* all user's cleaned up, mark it available */
1204         free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
1205         spin_lock(&dev->n_qps_lock);
1206         dev->n_qps_allocated--;
1207         spin_unlock(&dev->n_qps_lock);
1208
1209         if (qp->ip)
1210                 kref_put(&qp->ip->ref, qib_release_mmap_info);
1211         else
1212                 vfree(qp->r_rq.wq);
1213         vfree(qp->s_wq);
1214         kfree(qp->s_hdr);
1215         kfree(qp);
1216         return 0;
1217 }
1218
1219 /**
1220  * qib_init_qpn_table - initialize the QP number table for a device
1221  * @qpt: the QPN table
1222  */
1223 void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt)
1224 {
1225         spin_lock_init(&qpt->lock);
1226         qpt->last = 1;          /* start with QPN 2 */
1227         qpt->nmaps = 1;
1228         qpt->mask = dd->qpn_mask;
1229 }
1230
1231 /**
1232  * qib_free_qpn_table - free the QP number table for a device
1233  * @qpt: the QPN table
1234  */
1235 void qib_free_qpn_table(struct qib_qpn_table *qpt)
1236 {
1237         int i;
1238
1239         for (i = 0; i < ARRAY_SIZE(qpt->map); i++)
1240                 if (qpt->map[i].page)
1241                         free_page((unsigned long) qpt->map[i].page);
1242 }
1243
1244 /**
1245  * qib_get_credit - flush the send work queue of a QP
1246  * @qp: the qp who's send work queue to flush
1247  * @aeth: the Acknowledge Extended Transport Header
1248  *
1249  * The QP s_lock should be held.
1250  */
1251 void qib_get_credit(struct qib_qp *qp, u32 aeth)
1252 {
1253         u32 credit = (aeth >> QIB_AETH_CREDIT_SHIFT) & QIB_AETH_CREDIT_MASK;
1254
1255         /*
1256          * If the credit is invalid, we can send
1257          * as many packets as we like.  Otherwise, we have to
1258          * honor the credit field.
1259          */
1260         if (credit == QIB_AETH_CREDIT_INVAL) {
1261                 if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1262                         qp->s_flags |= QIB_S_UNLIMITED_CREDIT;
1263                         if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1264                                 qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1265                                 qib_schedule_send(qp);
1266                         }
1267                 }
1268         } else if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
1269                 /* Compute new LSN (i.e., MSN + credit) */
1270                 credit = (aeth + credit_table[credit]) & QIB_MSN_MASK;
1271                 if (qib_cmp24(credit, qp->s_lsn) > 0) {
1272                         qp->s_lsn = credit;
1273                         if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
1274                                 qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
1275                                 qib_schedule_send(qp);
1276                         }
1277                 }
1278         }
1279 }