drivers/infiniband/hw/ipath/ipath_qp.c

   1 /*
   2  * Copyright (c) 2006, 2007, 2008 QLogic Corporation. All rights reserved.
   3  * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/err.h>
  35 #include <linux/sched.h>
  36 #include <linux/slab.h>
  37 #include <linux/vmalloc.h>
  38
  39 #include "ipath_verbs.h"
  40 #include "ipath_kernel.h"
  41
  42 #define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
  43 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
  44 #define mk_qpn(qpt, map, off)   (((map) - (qpt)->map) * BITS_PER_PAGE + \
  45                                  (off))
  46 #define find_next_offset(map, off) find_next_zero_bit((map)->page, \
  47                                                       BITS_PER_PAGE, off)
  48
  49 /*
  50  * Convert the AETH credit code into the number of credits.
  51  */
  52 static u32 credit_table[31] = {
  53         0,                      /* 0 */
  54         1,                      /* 1 */
  55         2,                      /* 2 */
  56         3,                      /* 3 */
  57         4,                      /* 4 */
  58         6,                      /* 5 */
  59         8,                      /* 6 */
  60         12,                     /* 7 */
  61         16,                     /* 8 */
  62         24,                     /* 9 */
  63         32,                     /* A */
  64         48,                     /* B */
  65         64,                     /* C */
  66         96,                     /* D */
  67         128,                    /* E */
  68         192,                    /* F */
  69         256,                    /* 10 */
  70         384,                    /* 11 */
  71         512,                    /* 12 */
  72         768,                    /* 13 */
  73         1024,                   /* 14 */
  74         1536,                   /* 15 */
  75         2048,                   /* 16 */
  76         3072,                   /* 17 */
  77         4096,                   /* 18 */
  78         6144,                   /* 19 */
  79         8192,                   /* 1A */
  80         12288,                  /* 1B */
  81         16384,                  /* 1C */
  82         24576,                  /* 1D */
  83         32768                   /* 1E */
  84 };
  85
  86
  87 static void get_map_page(struct ipath_qp_table *qpt, struct qpn_map *map)
  88 {
  89         unsigned long page = get_zeroed_page(GFP_KERNEL);
  90         unsigned long flags;
  91
  92         /*
  93          * Free the page if someone raced with us installing it.
  94          */
  95
  96         spin_lock_irqsave(&qpt->lock, flags);
  97         if (map->page)
  98                 free_page(page);
  99         else
 100                 map->page = (void *)page;
 101         spin_unlock_irqrestore(&qpt->lock, flags);
 102 }
 103
 104
 105 static int alloc_qpn(struct ipath_qp_table *qpt, enum ib_qp_type type)
 106 {
 107         u32 i, offset, max_scan, qpn;
 108         struct qpn_map *map;
 109         u32 ret = -1;
 110
 111         if (type == IB_QPT_SMI)
 112                 ret = 0;
 113         else if (type == IB_QPT_GSI)
 114                 ret = 1;
 115
 116         if (ret != -1) {
 117                 map = &qpt->map[0];
 118                 if (unlikely(!map->page)) {
 119                         get_map_page(qpt, map);
 120                         if (unlikely(!map->page)) {
 121                                 ret = -ENOMEM;
 122                                 goto bail;
 123                         }
 124                 }
 125                 if (!test_and_set_bit(ret, map->page))
 126                         atomic_dec(&map->n_free);
 127                 else
 128                         ret = -EBUSY;
 129                 goto bail;
 130         }
 131
 132         qpn = qpt->last + 1;
 133         if (qpn >= QPN_MAX)
 134                 qpn = 2;
 135         offset = qpn & BITS_PER_PAGE_MASK;
 136         map = &qpt->map[qpn / BITS_PER_PAGE];
 137         max_scan = qpt->nmaps - !offset;
 138         for (i = 0;;) {
 139                 if (unlikely(!map->page)) {
 140                         get_map_page(qpt, map);
 141                         if (unlikely(!map->page))
 142                                 break;
 143                 }
 144                 if (likely(atomic_read(&map->n_free))) {
 145                         do {
 146                                 if (!test_and_set_bit(offset, map->page)) {
 147                                         atomic_dec(&map->n_free);
 148                                         qpt->last = qpn;
 149                                         ret = qpn;
 150                                         goto bail;
 151                                 }
 152                                 offset = find_next_offset(map, offset);
 153                                 qpn = mk_qpn(qpt, map, offset);
 154                                 /*
 155                                  * This test differs from alloc_pidmap().
 156                                  * If find_next_offset() does find a zero
 157                                  * bit, we don't need to check for QPN
 158                                  * wrapping around past our starting QPN.
 159                                  * We just need to be sure we don't loop
 160                                  * forever.
 161                                  */
 162                         } while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
 163                 }
 164                 /*
 165                  * In order to keep the number of pages allocated to a
 166                  * minimum, we scan the all existing pages before increasing
 167                  * the size of the bitmap table.
 168                  */
 169                 if (++i > max_scan) {
 170                         if (qpt->nmaps == QPNMAP_ENTRIES)
 171                                 break;
 172                         map = &qpt->map[qpt->nmaps++];
 173                         offset = 0;
 174                 } else if (map < &qpt->map[qpt->nmaps]) {
 175                         ++map;
 176                         offset = 0;
 177                 } else {
 178                         map = &qpt->map[0];
 179                         offset = 2;
 180                 }
 181                 qpn = mk_qpn(qpt, map, offset);
 182         }
 183
 184         ret = -ENOMEM;
 185
 186 bail:
 187         return ret;
 188 }
 189
 190 static void free_qpn(struct ipath_qp_table *qpt, u32 qpn)
 191 {
 192         struct qpn_map *map;
 193
 194         map = qpt->map + qpn / BITS_PER_PAGE;
 195         if (map->page)
 196                 clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
 197         atomic_inc(&map->n_free);
 198 }
 199
 200 /**
 201  * ipath_alloc_qpn - allocate a QP number
 202  * @qpt: the QP table
 203  * @qp: the QP
 204  * @type: the QP type (IB_QPT_SMI and IB_QPT_GSI are special)
 205  *
 206  * Allocate the next available QPN and put the QP into the hash table.
 207  * The hash table holds a reference to the QP.
 208  */
 209 static int ipath_alloc_qpn(struct ipath_qp_table *qpt, struct ipath_qp *qp,
 210                            enum ib_qp_type type)
 211 {
 212         unsigned long flags;
 213         int ret;
 214
 215         ret = alloc_qpn(qpt, type);
 216         if (ret < 0)
 217                 goto bail;
 218         qp->ibqp.qp_num = ret;
 219
 220         /* Add the QP to the hash table. */
 221         spin_lock_irqsave(&qpt->lock, flags);
 222
 223         ret %= qpt->max;
 224         qp->next = qpt->table[ret];
 225         qpt->table[ret] = qp;
 226         atomic_inc(&qp->refcount);
 227
 228         spin_unlock_irqrestore(&qpt->lock, flags);
 229         ret = 0;
 230
 231 bail:
 232         return ret;
 233 }
 234
 235 /**
 236  * ipath_free_qp - remove a QP from the QP table
 237  * @qpt: the QP table
 238  * @qp: the QP to remove
 239  *
 240  * Remove the QP from the table so it can't be found asynchronously by
 241  * the receive interrupt routine.
 242  */
 243 static void ipath_free_qp(struct ipath_qp_table *qpt, struct ipath_qp *qp)
 244 {
 245         struct ipath_qp *q, **qpp;
 246         unsigned long flags;
 247
 248         spin_lock_irqsave(&qpt->lock, flags);
 249
 250         /* Remove QP from the hash table. */
 251         qpp = &qpt->table[qp->ibqp.qp_num % qpt->max];
 252         for (; (q = *qpp) != NULL; qpp = &q->next) {
 253                 if (q == qp) {
 254                         *qpp = qp->next;
 255                         qp->next = NULL;
 256                         atomic_dec(&qp->refcount);
 257                         break;
 258                 }
 259         }
 260
 261         spin_unlock_irqrestore(&qpt->lock, flags);
 262 }
 263
 264 /**
 265  * ipath_free_all_qps - check for QPs still in use
 266  * @qpt: the QP table to empty
 267  *
 268  * There should not be any QPs still in use.
 269  * Free memory for table.
 270  */
 271 unsigned ipath_free_all_qps(struct ipath_qp_table *qpt)
 272 {
 273         unsigned long flags;
 274         struct ipath_qp *qp;
 275         u32 n, qp_inuse = 0;
 276
 277         spin_lock_irqsave(&qpt->lock, flags);
 278         for (n = 0; n < qpt->max; n++) {
 279                 qp = qpt->table[n];
 280                 qpt->table[n] = NULL;
 281
 282                 for (; qp; qp = qp->next)
 283                         qp_inuse++;
 284         }
 285         spin_unlock_irqrestore(&qpt->lock, flags);
 286
 287         for (n = 0; n < ARRAY_SIZE(qpt->map); n++)
 288                 if (qpt->map[n].page)
 289                         free_page((unsigned long) qpt->map[n].page);
 290         return qp_inuse;
 291 }
 292
 293 /**
 294  * ipath_lookup_qpn - return the QP with the given QPN
 295  * @qpt: the QP table
 296  * @qpn: the QP number to look up
 297  *
 298  * The caller is responsible for decrementing the QP reference count
 299  * when done.
 300  */
 301 struct ipath_qp *ipath_lookup_qpn(struct ipath_qp_table *qpt, u32 qpn)
 302 {
 303         unsigned long flags;
 304         struct ipath_qp *qp;
 305
 306         spin_lock_irqsave(&qpt->lock, flags);
 307
 308         for (qp = qpt->table[qpn % qpt->max]; qp; qp = qp->next) {
 309                 if (qp->ibqp.qp_num == qpn) {
 310                         atomic_inc(&qp->refcount);
 311                         break;
 312                 }
 313         }
 314
 315         spin_unlock_irqrestore(&qpt->lock, flags);
 316         return qp;
 317 }
 318
 319 /**
 320  * ipath_reset_qp - initialize the QP state to the reset state
 321  * @qp: the QP to reset
 322  * @type: the QP type
 323  */
 324 static void ipath_reset_qp(struct ipath_qp *qp, enum ib_qp_type type)
 325 {
 326         qp->remote_qpn = 0;
 327         qp->qkey = 0;
 328         qp->qp_access_flags = 0;
 329         atomic_set(&qp->s_dma_busy, 0);
 330         qp->s_flags &= IPATH_S_SIGNAL_REQ_WR;
 331         qp->s_hdrwords = 0;
 332         qp->s_wqe = NULL;
 333         qp->s_pkt_delay = 0;
 334         qp->s_draining = 0;
 335         qp->s_psn = 0;
 336         qp->r_psn = 0;
 337         qp->r_msn = 0;
 338         if (type == IB_QPT_RC) {
 339                 qp->s_state = IB_OPCODE_RC_SEND_LAST;
 340                 qp->r_state = IB_OPCODE_RC_SEND_LAST;
 341         } else {
 342                 qp->s_state = IB_OPCODE_UC_SEND_LAST;
 343                 qp->r_state = IB_OPCODE_UC_SEND_LAST;
 344         }
 345         qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
 346         qp->r_nak_state = 0;
 347         qp->r_aflags = 0;
 348         qp->r_flags = 0;
 349         qp->s_rnr_timeout = 0;
 350         qp->s_head = 0;
 351         qp->s_tail = 0;
 352         qp->s_cur = 0;
 353         qp->s_last = 0;
 354         qp->s_ssn = 1;
 355         qp->s_lsn = 0;
 356         memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
 357         qp->r_head_ack_queue = 0;
 358         qp->s_tail_ack_queue = 0;
 359         qp->s_num_rd_atomic = 0;
 360         if (qp->r_rq.wq) {
 361                 qp->r_rq.wq->head = 0;
 362                 qp->r_rq.wq->tail = 0;
 363         }
 364 }
 365
 366 /**
 367  * ipath_error_qp - put a QP into the error state
 368  * @qp: the QP to put into the error state
 369  * @err: the receive completion error to signal if a RWQE is active
 370  *
 371  * Flushes both send and receive work queues.
 372  * Returns true if last WQE event should be generated.
 373  * The QP s_lock should be held and interrupts disabled.
 374  * If we are already in error state, just return.
 375  */
 376
 377 int ipath_error_qp(struct ipath_qp *qp, enum ib_wc_status err)
 378 {
 379         struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
 380         struct ib_wc wc;
 381         int ret = 0;
 382
 383         if (qp->state == IB_QPS_ERR)
 384                 goto bail;
 385
 386         qp->state = IB_QPS_ERR;
 387
 388         spin_lock(&dev->pending_lock);
 389         if (!list_empty(&qp->timerwait))
 390                 list_del_init(&qp->timerwait);
 391         if (!list_empty(&qp->piowait))
 392                 list_del_init(&qp->piowait);
 393         spin_unlock(&dev->pending_lock);
 394
 395         /* Schedule the sending tasklet to drain the send work queue. */
 396         if (qp->s_last != qp->s_head)
 397                 ipath_schedule_send(qp);
 398
 399         memset(&wc, 0, sizeof(wc));
 400         wc.qp = &qp->ibqp;
 401         wc.opcode = IB_WC_RECV;
 402
 403         if (test_and_clear_bit(IPATH_R_WRID_VALID, &qp->r_aflags)) {
 404                 wc.wr_id = qp->r_wr_id;
 405                 wc.status = err;
 406                 ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 407         }
 408         wc.status = IB_WC_WR_FLUSH_ERR;
 409
 410         if (qp->r_rq.wq) {
 411                 struct ipath_rwq *wq;
 412                 u32 head;
 413                 u32 tail;
 414
 415                 spin_lock(&qp->r_rq.lock);
 416
 417                 /* sanity check pointers before trusting them */
 418                 wq = qp->r_rq.wq;
 419                 head = wq->head;
 420                 if (head >= qp->r_rq.size)
 421                         head = 0;
 422                 tail = wq->tail;
 423                 if (tail >= qp->r_rq.size)
 424                         tail = 0;
 425                 while (tail != head) {
 426                         wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
 427                         if (++tail >= qp->r_rq.size)
 428                                 tail = 0;
 429                         ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
 430                 }
 431                 wq->tail = tail;
 432
 433                 spin_unlock(&qp->r_rq.lock);
 434         } else if (qp->ibqp.event_handler)
 435                 ret = 1;
 436
 437 bail:
 438         return ret;
 439 }
 440
 441 /**
 442  * ipath_modify_qp - modify the attributes of a queue pair
 443  * @ibqp: the queue pair who's attributes we're modifying
 444  * @attr: the new attributes
 445  * @attr_mask: the mask of attributes to modify
 446  * @udata: user data for ipathverbs.so
 447  *
 448  * Returns 0 on success, otherwise returns an errno.
 449  */
 450 int ipath_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 451                     int attr_mask, struct ib_udata *udata)
 452 {
 453         struct ipath_ibdev *dev = to_idev(ibqp->device);
 454         struct ipath_qp *qp = to_iqp(ibqp);
 455         enum ib_qp_state cur_state, new_state;
 456         int lastwqe = 0;
 457         int ret;
 458
 459         spin_lock_irq(&qp->s_lock);
 460
 461         cur_state = attr_mask & IB_QP_CUR_STATE ?
 462                 attr->cur_qp_state : qp->state;
 463         new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
 464
 465         if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
 466                                 attr_mask, IB_LINK_LAYER_UNSPECIFIED))
 467                 goto inval;
 468
 469         if (attr_mask & IB_QP_AV) {
 470                 if (attr->ah_attr.dlid == 0 ||
 471                     attr->ah_attr.dlid >= IPATH_MULTICAST_LID_BASE)
 472                         goto inval;
 473
 474                 if ((attr->ah_attr.ah_flags & IB_AH_GRH) &&
 475                     (attr->ah_attr.grh.sgid_index > 1))
 476                         goto inval;
 477         }
 478
 479         if (attr_mask & IB_QP_PKEY_INDEX)
 480                 if (attr->pkey_index >= ipath_get_npkeys(dev->dd))
 481                         goto inval;
 482
 483         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 484                 if (attr->min_rnr_timer > 31)
 485                         goto inval;
 486
 487         if (attr_mask & IB_QP_PORT)
 488                 if (attr->port_num == 0 ||
 489                     attr->port_num > ibqp->device->phys_port_cnt)
 490                         goto inval;
 491
 492         /*
 493          * don't allow invalid Path MTU values or greater than 2048
 494          * unless we are configured for a 4KB MTU
 495          */
 496         if ((attr_mask & IB_QP_PATH_MTU) &&
 497                 (ib_mtu_enum_to_int(attr->path_mtu) == -1 ||
 498                 (attr->path_mtu > IB_MTU_2048 && !ipath_mtu4096)))
 499                 goto inval;
 500
 501         if (attr_mask & IB_QP_PATH_MIG_STATE)
 502                 if (attr->path_mig_state != IB_MIG_MIGRATED &&
 503                     attr->path_mig_state != IB_MIG_REARM)
 504                         goto inval;
 505
 506         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 507                 if (attr->max_dest_rd_atomic > IPATH_MAX_RDMA_ATOMIC)
 508                         goto inval;
 509
 510         switch (new_state) {
 511         case IB_QPS_RESET:
 512                 if (qp->state != IB_QPS_RESET) {
 513                         qp->state = IB_QPS_RESET;
 514                         spin_lock(&dev->pending_lock);
 515                         if (!list_empty(&qp->timerwait))
 516                                 list_del_init(&qp->timerwait);
 517                         if (!list_empty(&qp->piowait))
 518                                 list_del_init(&qp->piowait);
 519                         spin_unlock(&dev->pending_lock);
 520                         qp->s_flags &= ~IPATH_S_ANY_WAIT;
 521                         spin_unlock_irq(&qp->s_lock);
 522                         /* Stop the sending tasklet */
 523                         tasklet_kill(&qp->s_task);
 524                         wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
 525                         spin_lock_irq(&qp->s_lock);
 526                 }
 527                 ipath_reset_qp(qp, ibqp->qp_type);
 528                 break;
 529
 530         case IB_QPS_SQD:
 531                 qp->s_draining = qp->s_last != qp->s_cur;
 532                 qp->state = new_state;
 533                 break;
 534
 535         case IB_QPS_SQE:
 536                 if (qp->ibqp.qp_type == IB_QPT_RC)
 537                         goto inval;
 538                 qp->state = new_state;
 539                 break;
 540
 541         case IB_QPS_ERR:
 542                 lastwqe = ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR);
 543                 break;
 544
 545         default:
 546                 qp->state = new_state;
 547                 break;
 548         }
 549
 550         if (attr_mask & IB_QP_PKEY_INDEX)
 551                 qp->s_pkey_index = attr->pkey_index;
 552
 553         if (attr_mask & IB_QP_DEST_QPN)
 554                 qp->remote_qpn = attr->dest_qp_num;
 555
 556         if (attr_mask & IB_QP_SQ_PSN) {
 557                 qp->s_psn = qp->s_next_psn = attr->sq_psn;
 558                 qp->s_last_psn = qp->s_next_psn - 1;
 559         }
 560
 561         if (attr_mask & IB_QP_RQ_PSN)
 562                 qp->r_psn = attr->rq_psn;
 563
 564         if (attr_mask & IB_QP_ACCESS_FLAGS)
 565                 qp->qp_access_flags = attr->qp_access_flags;
 566
 567         if (attr_mask & IB_QP_AV) {
 568                 qp->remote_ah_attr = attr->ah_attr;
 569                 qp->s_dmult = ipath_ib_rate_to_mult(attr->ah_attr.static_rate);
 570         }
 571
 572         if (attr_mask & IB_QP_PATH_MTU)
 573                 qp->path_mtu = attr->path_mtu;
 574
 575         if (attr_mask & IB_QP_RETRY_CNT)
 576                 qp->s_retry = qp->s_retry_cnt = attr->retry_cnt;
 577
 578         if (attr_mask & IB_QP_RNR_RETRY) {
 579                 qp->s_rnr_retry = attr->rnr_retry;
 580                 if (qp->s_rnr_retry > 7)
 581                         qp->s_rnr_retry = 7;
 582                 qp->s_rnr_retry_cnt = qp->s_rnr_retry;
 583         }
 584
 585         if (attr_mask & IB_QP_MIN_RNR_TIMER)
 586                 qp->r_min_rnr_timer = attr->min_rnr_timer;
 587
 588         if (attr_mask & IB_QP_TIMEOUT)
 589                 qp->timeout = attr->timeout;
 590
 591         if (attr_mask & IB_QP_QKEY)
 592                 qp->qkey = attr->qkey;
 593
 594         if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
 595                 qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
 596
 597         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
 598                 qp->s_max_rd_atomic = attr->max_rd_atomic;
 599
 600         spin_unlock_irq(&qp->s_lock);
 601
 602         if (lastwqe) {
 603                 struct ib_event ev;
 604
 605                 ev.device = qp->ibqp.device;
 606                 ev.element.qp = &qp->ibqp;
 607                 ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
 608                 qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
 609         }
 610         ret = 0;
 611         goto bail;
 612
 613 inval:
 614         spin_unlock_irq(&qp->s_lock);
 615         ret = -EINVAL;
 616
 617 bail:
 618         return ret;
 619 }
 620
 621 int ipath_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 622                    int attr_mask, struct ib_qp_init_attr *init_attr)
 623 {
 624         struct ipath_qp *qp = to_iqp(ibqp);
 625
 626         attr->qp_state = qp->state;
 627         attr->cur_qp_state = attr->qp_state;
 628         attr->path_mtu = qp->path_mtu;
 629         attr->path_mig_state = 0;
 630         attr->qkey = qp->qkey;
 631         attr->rq_psn = qp->r_psn;
 632         attr->sq_psn = qp->s_next_psn;
 633         attr->dest_qp_num = qp->remote_qpn;
 634         attr->qp_access_flags = qp->qp_access_flags;
 635         attr->cap.max_send_wr = qp->s_size - 1;
 636         attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
 637         attr->cap.max_send_sge = qp->s_max_sge;
 638         attr->cap.max_recv_sge = qp->r_rq.max_sge;
 639         attr->cap.max_inline_data = 0;
 640         attr->ah_attr = qp->remote_ah_attr;
 641         memset(&attr->alt_ah_attr, 0, sizeof(attr->alt_ah_attr));
 642         attr->pkey_index = qp->s_pkey_index;
 643         attr->alt_pkey_index = 0;
 644         attr->en_sqd_async_notify = 0;
 645         attr->sq_draining = qp->s_draining;
 646         attr->max_rd_atomic = qp->s_max_rd_atomic;
 647         attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
 648         attr->min_rnr_timer = qp->r_min_rnr_timer;
 649         attr->port_num = 1;
 650         attr->timeout = qp->timeout;
 651         attr->retry_cnt = qp->s_retry_cnt;
 652         attr->rnr_retry = qp->s_rnr_retry_cnt;
 653         attr->alt_port_num = 0;
 654         attr->alt_timeout = 0;
 655
 656         init_attr->event_handler = qp->ibqp.event_handler;
 657         init_attr->qp_context = qp->ibqp.qp_context;
 658         init_attr->send_cq = qp->ibqp.send_cq;
 659         init_attr->recv_cq = qp->ibqp.recv_cq;
 660         init_attr->srq = qp->ibqp.srq;
 661         init_attr->cap = attr->cap;
 662         if (qp->s_flags & IPATH_S_SIGNAL_REQ_WR)
 663                 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
 664         else
 665                 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
 666         init_attr->qp_type = qp->ibqp.qp_type;
 667         init_attr->port_num = 1;
 668         return 0;
 669 }
 670
 671 /**
 672  * ipath_compute_aeth - compute the AETH (syndrome + MSN)
 673  * @qp: the queue pair to compute the AETH for
 674  *
 675  * Returns the AETH.
 676  */
 677 __be32 ipath_compute_aeth(struct ipath_qp *qp)
 678 {
 679         u32 aeth = qp->r_msn & IPATH_MSN_MASK;
 680
 681         if (qp->ibqp.srq) {
 682                 /*
 683                  * Shared receive queues don't generate credits.
 684                  * Set the credit field to the invalid value.
 685                  */
 686                 aeth |= IPATH_AETH_CREDIT_INVAL << IPATH_AETH_CREDIT_SHIFT;
 687         } else {
 688                 u32 min, max, x;
 689                 u32 credits;
 690                 struct ipath_rwq *wq = qp->r_rq.wq;
 691                 u32 head;
 692                 u32 tail;
 693
 694                 /* sanity check pointers before trusting them */
 695                 head = wq->head;
 696                 if (head >= qp->r_rq.size)
 697                         head = 0;
 698                 tail = wq->tail;
 699                 if (tail >= qp->r_rq.size)
 700                         tail = 0;
 701                 /*
 702                  * Compute the number of credits available (RWQEs).
 703                  * XXX Not holding the r_rq.lock here so there is a small
 704                  * chance that the pair of reads are not atomic.
 705                  */
 706                 credits = head - tail;
 707                 if ((int)credits < 0)
 708                         credits += qp->r_rq.size;
 709                 /*
 710                  * Binary search the credit table to find the code to
 711                  * use.
 712                  */
 713                 min = 0;
 714                 max = 31;
 715                 for (;;) {
 716                         x = (min + max) / 2;
 717                         if (credit_table[x] == credits)
 718                                 break;
 719                         if (credit_table[x] > credits)
 720                                 max = x;
 721                         else if (min == x)
 722                                 break;
 723                         else
 724                                 min = x;
 725                 }
 726                 aeth |= x << IPATH_AETH_CREDIT_SHIFT;
 727         }
 728         return cpu_to_be32(aeth);
 729 }
 730
 731 /**
 732  * ipath_create_qp - create a queue pair for a device
 733  * @ibpd: the protection domain who's device we create the queue pair for
 734  * @init_attr: the attributes of the queue pair
 735  * @udata: unused by InfiniPath
 736  *
 737  * Returns the queue pair on success, otherwise returns an errno.
 738  *
 739  * Called by the ib_create_qp() core verbs function.
 740  */
 741 struct ib_qp *ipath_create_qp(struct ib_pd *ibpd,
 742                               struct ib_qp_init_attr *init_attr,
 743                               struct ib_udata *udata)
 744 {
 745         struct ipath_qp *qp;
 746         int err;
 747         struct ipath_swqe *swq = NULL;
 748         struct ipath_ibdev *dev;
 749         size_t sz;
 750         size_t sg_list_sz;
 751         struct ib_qp *ret;
 752
 753         if (init_attr->create_flags) {
 754                 ret = ERR_PTR(-EINVAL);
 755                 goto bail;
 756         }
 757
 758         if (init_attr->cap.max_send_sge > ib_ipath_max_sges ||
 759             init_attr->cap.max_send_wr > ib_ipath_max_qp_wrs) {
 760                 ret = ERR_PTR(-EINVAL);
 761                 goto bail;
 762         }
 763
 764         /* Check receive queue parameters if no SRQ is specified. */
 765         if (!init_attr->srq) {
 766                 if (init_attr->cap.max_recv_sge > ib_ipath_max_sges ||
 767                     init_attr->cap.max_recv_wr > ib_ipath_max_qp_wrs) {
 768                         ret = ERR_PTR(-EINVAL);
 769                         goto bail;
 770                 }
 771                 if (init_attr->cap.max_send_sge +
 772                     init_attr->cap.max_send_wr +
 773                     init_attr->cap.max_recv_sge +
 774                     init_attr->cap.max_recv_wr == 0) {
 775                         ret = ERR_PTR(-EINVAL);
 776                         goto bail;
 777                 }
 778         }
 779
 780         switch (init_attr->qp_type) {
 781         case IB_QPT_UC:
 782         case IB_QPT_RC:
 783         case IB_QPT_UD:
 784         case IB_QPT_SMI:
 785         case IB_QPT_GSI:
 786                 sz = sizeof(struct ipath_sge) *
 787                         init_attr->cap.max_send_sge +
 788                         sizeof(struct ipath_swqe);
 789                 swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
 790                 if (swq == NULL) {
 791                         ret = ERR_PTR(-ENOMEM);
 792                         goto bail;
 793                 }
 794                 sz = sizeof(*qp);
 795                 sg_list_sz = 0;
 796                 if (init_attr->srq) {
 797                         struct ipath_srq *srq = to_isrq(init_attr->srq);
 798
 799                         if (srq->rq.max_sge > 1)
 800                                 sg_list_sz = sizeof(*qp->r_sg_list) *
 801                                         (srq->rq.max_sge - 1);
 802                 } else if (init_attr->cap.max_recv_sge > 1)
 803                         sg_list_sz = sizeof(*qp->r_sg_list) *
 804                                 (init_attr->cap.max_recv_sge - 1);
 805                 qp = kmalloc(sz + sg_list_sz, GFP_KERNEL);
 806                 if (!qp) {
 807                         ret = ERR_PTR(-ENOMEM);
 808                         goto bail_swq;
 809                 }
 810                 if (sg_list_sz && (init_attr->qp_type == IB_QPT_UD ||
 811                     init_attr->qp_type == IB_QPT_SMI ||
 812                     init_attr->qp_type == IB_QPT_GSI)) {
 813                         qp->r_ud_sg_list = kmalloc(sg_list_sz, GFP_KERNEL);
 814                         if (!qp->r_ud_sg_list) {
 815                                 ret = ERR_PTR(-ENOMEM);
 816                                 goto bail_qp;
 817                         }
 818                 } else
 819                         qp->r_ud_sg_list = NULL;
 820                 if (init_attr->srq) {
 821                         sz = 0;
 822                         qp->r_rq.size = 0;
 823                         qp->r_rq.max_sge = 0;
 824                         qp->r_rq.wq = NULL;
 825                         init_attr->cap.max_recv_wr = 0;
 826                         init_attr->cap.max_recv_sge = 0;
 827                 } else {
 828                         qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
 829                         qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
 830                         sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
 831                                 sizeof(struct ipath_rwqe);
 832                         qp->r_rq.wq = vmalloc_user(sizeof(struct ipath_rwq) +
 833                                               qp->r_rq.size * sz);
 834                         if (!qp->r_rq.wq) {
 835                                 ret = ERR_PTR(-ENOMEM);
 836                                 goto bail_sg_list;
 837                         }
 838                 }
 839
 840                 /*
 841                  * ib_create_qp() will initialize qp->ibqp
 842                  * except for qp->ibqp.qp_num.
 843                  */
 844                 spin_lock_init(&qp->s_lock);
 845                 spin_lock_init(&qp->r_rq.lock);
 846                 atomic_set(&qp->refcount, 0);
 847                 init_waitqueue_head(&qp->wait);
 848                 init_waitqueue_head(&qp->wait_dma);
 849                 tasklet_init(&qp->s_task, ipath_do_send, (unsigned long)qp);
 850                 INIT_LIST_HEAD(&qp->piowait);
 851                 INIT_LIST_HEAD(&qp->timerwait);
 852                 qp->state = IB_QPS_RESET;
 853                 qp->s_wq = swq;
 854                 qp->s_size = init_attr->cap.max_send_wr + 1;
 855                 qp->s_max_sge = init_attr->cap.max_send_sge;
 856                 if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
 857                         qp->s_flags = IPATH_S_SIGNAL_REQ_WR;
 858                 else
 859                         qp->s_flags = 0;
 860                 dev = to_idev(ibpd->device);
 861                 err = ipath_alloc_qpn(&dev->qp_table, qp,
 862                                       init_attr->qp_type);
 863                 if (err) {
 864                         ret = ERR_PTR(err);
 865                         vfree(qp->r_rq.wq);
 866                         goto bail_sg_list;
 867                 }
 868                 qp->ip = NULL;
 869                 qp->s_tx = NULL;
 870                 ipath_reset_qp(qp, init_attr->qp_type);
 871                 break;
 872
 873         default:
 874                 /* Don't support raw QPs */
 875                 ret = ERR_PTR(-ENOSYS);
 876                 goto bail;
 877         }
 878
 879         init_attr->cap.max_inline_data = 0;
 880
 881         /*
 882          * Return the address of the RWQ as the offset to mmap.
 883          * See ipath_mmap() for details.
 884          */
 885         if (udata && udata->outlen >= sizeof(__u64)) {
 886                 if (!qp->r_rq.wq) {
 887                         __u64 offset = 0;
 888
 889                         err = ib_copy_to_udata(udata, &offset,
 890                                                sizeof(offset));
 891                         if (err) {
 892                                 ret = ERR_PTR(err);
 893                                 goto bail_ip;
 894                         }
 895                 } else {
 896                         u32 s = sizeof(struct ipath_rwq) +
 897                                 qp->r_rq.size * sz;
 898
 899                         qp->ip =
 900                             ipath_create_mmap_info(dev, s,
 901                                                    ibpd->uobject->context,
 902                                                    qp->r_rq.wq);
 903                         if (!qp->ip) {
 904                                 ret = ERR_PTR(-ENOMEM);
 905                                 goto bail_ip;
 906                         }
 907
 908                         err = ib_copy_to_udata(udata, &(qp->ip->offset),
 909                                                sizeof(qp->ip->offset));
 910                         if (err) {
 911                                 ret = ERR_PTR(err);
 912                                 goto bail_ip;
 913                         }
 914                 }
 915         }
 916
 917         spin_lock(&dev->n_qps_lock);
 918         if (dev->n_qps_allocated == ib_ipath_max_qps) {
 919                 spin_unlock(&dev->n_qps_lock);
 920                 ret = ERR_PTR(-ENOMEM);
 921                 goto bail_ip;
 922         }
 923
 924         dev->n_qps_allocated++;
 925         spin_unlock(&dev->n_qps_lock);
 926
 927         if (qp->ip) {
 928                 spin_lock_irq(&dev->pending_lock);
 929                 list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
 930                 spin_unlock_irq(&dev->pending_lock);
 931         }
 932
 933         ret = &qp->ibqp;
 934         goto bail;
 935
 936 bail_ip:
 937         if (qp->ip)
 938                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
 939         else
 940                 vfree(qp->r_rq.wq);
 941         ipath_free_qp(&dev->qp_table, qp);
 942         free_qpn(&dev->qp_table, qp->ibqp.qp_num);
 943 bail_sg_list:
 944         kfree(qp->r_ud_sg_list);
 945 bail_qp:
 946         kfree(qp);
 947 bail_swq:
 948         vfree(swq);
 949 bail:
 950         return ret;
 951 }
 952
 953 /**
 954  * ipath_destroy_qp - destroy a queue pair
 955  * @ibqp: the queue pair to destroy
 956  *
 957  * Returns 0 on success.
 958  *
 959  * Note that this can be called while the QP is actively sending or
 960  * receiving!
 961  */
 962 int ipath_destroy_qp(struct ib_qp *ibqp)
 963 {
 964         struct ipath_qp *qp = to_iqp(ibqp);
 965         struct ipath_ibdev *dev = to_idev(ibqp->device);
 966
 967         /* Make sure HW and driver activity is stopped. */
 968         spin_lock_irq(&qp->s_lock);
 969         if (qp->state != IB_QPS_RESET) {
 970                 qp->state = IB_QPS_RESET;
 971                 spin_lock(&dev->pending_lock);
 972                 if (!list_empty(&qp->timerwait))
 973                         list_del_init(&qp->timerwait);
 974                 if (!list_empty(&qp->piowait))
 975                         list_del_init(&qp->piowait);
 976                 spin_unlock(&dev->pending_lock);
 977                 qp->s_flags &= ~IPATH_S_ANY_WAIT;
 978                 spin_unlock_irq(&qp->s_lock);
 979                 /* Stop the sending tasklet */
 980                 tasklet_kill(&qp->s_task);
 981                 wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
 982         } else
 983                 spin_unlock_irq(&qp->s_lock);
 984
 985         ipath_free_qp(&dev->qp_table, qp);
 986
 987         if (qp->s_tx) {
 988                 atomic_dec(&qp->refcount);
 989                 if (qp->s_tx->txreq.flags & IPATH_SDMA_TXREQ_F_FREEBUF)
 990                         kfree(qp->s_tx->txreq.map_addr);
 991                 spin_lock_irq(&dev->pending_lock);
 992                 list_add(&qp->s_tx->txreq.list, &dev->txreq_free);
 993                 spin_unlock_irq(&dev->pending_lock);
 994                 qp->s_tx = NULL;
 995         }
 996
 997         wait_event(qp->wait, !atomic_read(&qp->refcount));
 998
 999         /* all user's cleaned up, mark it available */
1000         free_qpn(&dev->qp_table, qp->ibqp.qp_num);
1001         spin_lock(&dev->n_qps_lock);
1002         dev->n_qps_allocated--;
1003         spin_unlock(&dev->n_qps_lock);
1004
1005         if (qp->ip)
1006                 kref_put(&qp->ip->ref, ipath_release_mmap_info);
1007         else
1008                 vfree(qp->r_rq.wq);
1009         kfree(qp->r_ud_sg_list);
1010         vfree(qp->s_wq);
1011         kfree(qp);
1012         return 0;
1013 }
1014
1015 /**
1016  * ipath_init_qp_table - initialize the QP table for a device
1017  * @idev: the device who's QP table we're initializing
1018  * @size: the size of the QP table
1019  *
1020  * Returns 0 on success, otherwise returns an errno.
1021  */
1022 int ipath_init_qp_table(struct ipath_ibdev *idev, int size)
1023 {
1024         int i;
1025         int ret;
1026
1027         idev->qp_table.last = 1;        /* QPN 0 and 1 are special. */
1028         idev->qp_table.max = size;
1029         idev->qp_table.nmaps = 1;
1030         idev->qp_table.table = kzalloc(size * sizeof(*idev->qp_table.table),
1031                                        GFP_KERNEL);
1032         if (idev->qp_table.table == NULL) {
1033                 ret = -ENOMEM;
1034                 goto bail;
1035         }
1036
1037         for (i = 0; i < ARRAY_SIZE(idev->qp_table.map); i++) {
1038                 atomic_set(&idev->qp_table.map[i].n_free, BITS_PER_PAGE);
1039                 idev->qp_table.map[i].page = NULL;
1040         }
1041
1042         ret = 0;
1043
1044 bail:
1045         return ret;
1046 }
1047
1048 /**
1049  * ipath_get_credit - flush the send work queue of a QP
1050  * @qp: the qp who's send work queue to flush
1051  * @aeth: the Acknowledge Extended Transport Header
1052  *
1053  * The QP s_lock should be held.
1054  */
1055 void ipath_get_credit(struct ipath_qp *qp, u32 aeth)
1056 {
1057         u32 credit = (aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK;
1058
1059         /*
1060          * If the credit is invalid, we can send
1061          * as many packets as we like.  Otherwise, we have to
1062          * honor the credit field.
1063          */
1064         if (credit == IPATH_AETH_CREDIT_INVAL)
1065                 qp->s_lsn = (u32) -1;
1066         else if (qp->s_lsn != (u32) -1) {
1067                 /* Compute new LSN (i.e., MSN + credit) */
1068                 credit = (aeth + credit_table[credit]) & IPATH_MSN_MASK;
1069                 if (ipath_cmp24(credit, qp->s_lsn) > 0)
1070                         qp->s_lsn = credit;
1071         }
1072
1073         /* Restart sending if it was blocked due to lack of credits. */
1074         if ((qp->s_flags & IPATH_S_WAIT_SSN_CREDIT) &&
1075             qp->s_cur != qp->s_head &&
1076             (qp->s_lsn == (u32) -1 ||
1077              ipath_cmp24(get_swqe_ptr(qp, qp->s_cur)->ssn,
1078                          qp->s_lsn + 1) <= 0))
1079                 ipath_schedule_send(qp);
1080 }