drivers/infiniband/hw/mthca/mthca_srq.c

   1 /*
   2  * Copyright (c) 2005 Cisco Systems. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  *
  32  * $Id: mthca_srq.c 3047 2005-08-10 03:59:35Z roland $
  33  */
  34
  35 #include <linux/slab.h>
  36 #include <linux/string.h>
  37
  38 #include <asm/io.h>
  39
  40 #include "mthca_dev.h"
  41 #include "mthca_cmd.h"
  42 #include "mthca_memfree.h"
  43 #include "mthca_wqe.h"
  44
  45 enum {
  46         MTHCA_MAX_DIRECT_SRQ_SIZE = 4 * PAGE_SIZE
  47 };
  48
  49 struct mthca_tavor_srq_context {
  50         __be64 wqe_base_ds;     /* low 6 bits is descriptor size */
  51         __be32 state_pd;
  52         __be32 lkey;
  53         __be32 uar;
  54         __be16 limit_watermark;
  55         __be16 wqe_cnt;
  56         u32    reserved[2];
  57 };
  58
  59 struct mthca_arbel_srq_context {
  60         __be32 state_logsize_srqn;
  61         __be32 lkey;
  62         __be32 db_index;
  63         __be32 logstride_usrpage;
  64         __be64 wqe_base;
  65         __be32 eq_pd;
  66         __be16 limit_watermark;
  67         __be16 wqe_cnt;
  68         u16    reserved1;
  69         __be16 wqe_counter;
  70         u32    reserved2[3];
  71 };
  72
  73 static void *get_wqe(struct mthca_srq *srq, int n)
  74 {
  75         if (srq->is_direct)
  76                 return srq->queue.direct.buf + (n << srq->wqe_shift);
  77         else
  78                 return srq->queue.page_list[(n << srq->wqe_shift) >> PAGE_SHIFT].buf +
  79                         ((n << srq->wqe_shift) & (PAGE_SIZE - 1));
  80 }
  81
  82 /*
  83  * Return a pointer to the location within a WQE that we're using as a
  84  * link when the WQE is in the free list.  We use the imm field
  85  * because in the Tavor case, posting a WQE may overwrite the next
  86  * segment of the previous WQE, but a receive WQE will never touch the
  87  * imm field.  This avoids corrupting our free list if the previous
  88  * WQE has already completed and been put on the free list when we
  89  * post the next WQE.
  90  */
  91 static inline int *wqe_to_link(void *wqe)
  92 {
  93         return (int *) (wqe + offsetof(struct mthca_next_seg, imm));
  94 }
  95
  96 static void mthca_tavor_init_srq_context(struct mthca_dev *dev,
  97                                          struct mthca_pd *pd,
  98                                          struct mthca_srq *srq,
  99                                          struct mthca_tavor_srq_context *context)
 100 {
 101         memset(context, 0, sizeof *context);
 102
 103         context->wqe_base_ds = cpu_to_be64(1 << (srq->wqe_shift - 4));
 104         context->state_pd    = cpu_to_be32(pd->pd_num);
 105         context->lkey        = cpu_to_be32(srq->mr.ibmr.lkey);
 106
 107         if (pd->ibpd.uobject)
 108                 context->uar =
 109                         cpu_to_be32(to_mucontext(pd->ibpd.uobject->context)->uar.index);
 110         else
 111                 context->uar = cpu_to_be32(dev->driver_uar.index);
 112 }
 113
 114 static void mthca_arbel_init_srq_context(struct mthca_dev *dev,
 115                                          struct mthca_pd *pd,
 116                                          struct mthca_srq *srq,
 117                                          struct mthca_arbel_srq_context *context)
 118 {
 119         int logsize, max;
 120
 121         memset(context, 0, sizeof *context);
 122
 123         /*
 124          * Put max in a temporary variable to work around gcc bug
 125          * triggered by ilog2() on sparc64.
 126          */
 127         max = srq->max;
 128         logsize = ilog2(max);
 129         context->state_logsize_srqn = cpu_to_be32(logsize << 24 | srq->srqn);
 130         context->lkey = cpu_to_be32(srq->mr.ibmr.lkey);
 131         context->db_index = cpu_to_be32(srq->db_index);
 132         context->logstride_usrpage = cpu_to_be32((srq->wqe_shift - 4) << 29);
 133         if (pd->ibpd.uobject)
 134                 context->logstride_usrpage |=
 135                         cpu_to_be32(to_mucontext(pd->ibpd.uobject->context)->uar.index);
 136         else
 137                 context->logstride_usrpage |= cpu_to_be32(dev->driver_uar.index);
 138         context->eq_pd = cpu_to_be32(MTHCA_EQ_ASYNC << 24 | pd->pd_num);
 139 }
 140
 141 static void mthca_free_srq_buf(struct mthca_dev *dev, struct mthca_srq *srq)
 142 {
 143         mthca_buf_free(dev, srq->max << srq->wqe_shift, &srq->queue,
 144                        srq->is_direct, &srq->mr);
 145         kfree(srq->wrid);
 146 }
 147
 148 static int mthca_alloc_srq_buf(struct mthca_dev *dev, struct mthca_pd *pd,
 149                                struct mthca_srq *srq)
 150 {
 151         struct mthca_data_seg *scatter;
 152         void *wqe;
 153         int err;
 154         int i;
 155
 156         if (pd->ibpd.uobject)
 157                 return 0;
 158
 159         srq->wrid = kmalloc(srq->max * sizeof (u64), GFP_KERNEL);
 160         if (!srq->wrid)
 161                 return -ENOMEM;
 162
 163         err = mthca_buf_alloc(dev, srq->max << srq->wqe_shift,
 164                               MTHCA_MAX_DIRECT_SRQ_SIZE,
 165                               &srq->queue, &srq->is_direct, pd, 1, &srq->mr);
 166         if (err) {
 167                 kfree(srq->wrid);
 168                 return err;
 169         }
 170
 171         /*
 172          * Now initialize the SRQ buffer so that all of the WQEs are
 173          * linked into the list of free WQEs.  In addition, set the
 174          * scatter list L_Keys to the sentry value of 0x100.
 175          */
 176         for (i = 0; i < srq->max; ++i) {
 177                 wqe = get_wqe(srq, i);
 178
 179                 *wqe_to_link(wqe) = i < srq->max - 1 ? i + 1 : -1;
 180
 181                 for (scatter = wqe + sizeof (struct mthca_next_seg);
 182                      (void *) scatter < wqe + (1 << srq->wqe_shift);
 183                      ++scatter)
 184                         scatter->lkey = cpu_to_be32(MTHCA_INVAL_LKEY);
 185         }
 186
 187         srq->last = get_wqe(srq, srq->max - 1);
 188
 189         return 0;
 190 }
 191
 192 int mthca_alloc_srq(struct mthca_dev *dev, struct mthca_pd *pd,
 193                     struct ib_srq_attr *attr, struct mthca_srq *srq)
 194 {
 195         struct mthca_mailbox *mailbox;
 196         u8 status;
 197         int ds;
 198         int err;
 199
 200         /* Sanity check SRQ size before proceeding */
 201         if (attr->max_wr  > dev->limits.max_srq_wqes ||
 202             attr->max_sge > dev->limits.max_srq_sge)
 203                 return -EINVAL;
 204
 205         srq->max      = attr->max_wr;
 206         srq->max_gs   = attr->max_sge;
 207         srq->counter  = 0;
 208
 209         if (mthca_is_memfree(dev))
 210                 srq->max = roundup_pow_of_two(srq->max + 1);
 211         else
 212                 srq->max = srq->max + 1;
 213
 214         ds = max(64UL,
 215                  roundup_pow_of_two(sizeof (struct mthca_next_seg) +
 216                                     srq->max_gs * sizeof (struct mthca_data_seg)));
 217
 218         if (!mthca_is_memfree(dev) && (ds > dev->limits.max_desc_sz))
 219                 return -EINVAL;
 220
 221         srq->wqe_shift = ilog2(ds);
 222
 223         srq->srqn = mthca_alloc(&dev->srq_table.alloc);
 224         if (srq->srqn == -1)
 225                 return -ENOMEM;
 226
 227         if (mthca_is_memfree(dev)) {
 228                 err = mthca_table_get(dev, dev->srq_table.table, srq->srqn);
 229                 if (err)
 230                         goto err_out;
 231
 232                 if (!pd->ibpd.uobject) {
 233                         srq->db_index = mthca_alloc_db(dev, MTHCA_DB_TYPE_SRQ,
 234                                                        srq->srqn, &srq->db);
 235                         if (srq->db_index < 0) {
 236                                 err = -ENOMEM;
 237                                 goto err_out_icm;
 238                         }
 239                 }
 240         }
 241
 242         mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
 243         if (IS_ERR(mailbox)) {
 244                 err = PTR_ERR(mailbox);
 245                 goto err_out_db;
 246         }
 247
 248         err = mthca_alloc_srq_buf(dev, pd, srq);
 249         if (err)
 250                 goto err_out_mailbox;
 251
 252         spin_lock_init(&srq->lock);
 253         srq->refcount = 1;
 254         init_waitqueue_head(&srq->wait);
 255         mutex_init(&srq->mutex);
 256
 257         if (mthca_is_memfree(dev))
 258                 mthca_arbel_init_srq_context(dev, pd, srq, mailbox->buf);
 259         else
 260                 mthca_tavor_init_srq_context(dev, pd, srq, mailbox->buf);
 261
 262         err = mthca_SW2HW_SRQ(dev, mailbox, srq->srqn, &status);
 263
 264         if (err) {
 265                 mthca_warn(dev, "SW2HW_SRQ failed (%d)\n", err);
 266                 goto err_out_free_buf;
 267         }
 268         if (status) {
 269                 mthca_warn(dev, "SW2HW_SRQ returned status 0x%02x\n",
 270                            status);
 271                 err = -EINVAL;
 272                 goto err_out_free_buf;
 273         }
 274
 275         spin_lock_irq(&dev->srq_table.lock);
 276         if (mthca_array_set(&dev->srq_table.srq,
 277                             srq->srqn & (dev->limits.num_srqs - 1),
 278                             srq)) {
 279                 spin_unlock_irq(&dev->srq_table.lock);
 280                 goto err_out_free_srq;
 281         }
 282         spin_unlock_irq(&dev->srq_table.lock);
 283
 284         mthca_free_mailbox(dev, mailbox);
 285
 286         srq->first_free = 0;
 287         srq->last_free  = srq->max - 1;
 288
 289         attr->max_wr    = srq->max - 1;
 290         attr->max_sge   = srq->max_gs;
 291
 292         return 0;
 293
 294 err_out_free_srq:
 295         err = mthca_HW2SW_SRQ(dev, mailbox, srq->srqn, &status);
 296         if (err)
 297                 mthca_warn(dev, "HW2SW_SRQ failed (%d)\n", err);
 298         else if (status)
 299                 mthca_warn(dev, "HW2SW_SRQ returned status 0x%02x\n", status);
 300
 301 err_out_free_buf:
 302         if (!pd->ibpd.uobject)
 303                 mthca_free_srq_buf(dev, srq);
 304
 305 err_out_mailbox:
 306         mthca_free_mailbox(dev, mailbox);
 307
 308 err_out_db:
 309         if (!pd->ibpd.uobject && mthca_is_memfree(dev))
 310                 mthca_free_db(dev, MTHCA_DB_TYPE_SRQ, srq->db_index);
 311
 312 err_out_icm:
 313         mthca_table_put(dev, dev->srq_table.table, srq->srqn);
 314
 315 err_out:
 316         mthca_free(&dev->srq_table.alloc, srq->srqn);
 317
 318         return err;
 319 }
 320
 321 static inline int get_srq_refcount(struct mthca_dev *dev, struct mthca_srq *srq)
 322 {
 323         int c;
 324
 325         spin_lock_irq(&dev->srq_table.lock);
 326         c = srq->refcount;
 327         spin_unlock_irq(&dev->srq_table.lock);
 328
 329         return c;
 330 }
 331
 332 void mthca_free_srq(struct mthca_dev *dev, struct mthca_srq *srq)
 333 {
 334         struct mthca_mailbox *mailbox;
 335         int err;
 336         u8 status;
 337
 338         mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
 339         if (IS_ERR(mailbox)) {
 340                 mthca_warn(dev, "No memory for mailbox to free SRQ.\n");
 341                 return;
 342         }
 343
 344         err = mthca_HW2SW_SRQ(dev, mailbox, srq->srqn, &status);
 345         if (err)
 346                 mthca_warn(dev, "HW2SW_SRQ failed (%d)\n", err);
 347         else if (status)
 348                 mthca_warn(dev, "HW2SW_SRQ returned status 0x%02x\n", status);
 349
 350         spin_lock_irq(&dev->srq_table.lock);
 351         mthca_array_clear(&dev->srq_table.srq,
 352                           srq->srqn & (dev->limits.num_srqs - 1));
 353         --srq->refcount;
 354         spin_unlock_irq(&dev->srq_table.lock);
 355
 356         wait_event(srq->wait, !get_srq_refcount(dev, srq));
 357
 358         if (!srq->ibsrq.uobject) {
 359                 mthca_free_srq_buf(dev, srq);
 360                 if (mthca_is_memfree(dev))
 361                         mthca_free_db(dev, MTHCA_DB_TYPE_SRQ, srq->db_index);
 362         }
 363
 364         mthca_table_put(dev, dev->srq_table.table, srq->srqn);
 365         mthca_free(&dev->srq_table.alloc, srq->srqn);
 366         mthca_free_mailbox(dev, mailbox);
 367 }
 368
 369 int mthca_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
 370                      enum ib_srq_attr_mask attr_mask, struct ib_udata *udata)
 371 {
 372         struct mthca_dev *dev = to_mdev(ibsrq->device);
 373         struct mthca_srq *srq = to_msrq(ibsrq);
 374         int ret;
 375         u8 status;
 376
 377         /* We don't support resizing SRQs (yet?) */
 378         if (attr_mask & IB_SRQ_MAX_WR)
 379                 return -EINVAL;
 380
 381         if (attr_mask & IB_SRQ_LIMIT) {
 382                 u32 max_wr = mthca_is_memfree(dev) ? srq->max - 1 : srq->max;
 383                 if (attr->srq_limit > max_wr)
 384                         return -EINVAL;
 385
 386                 mutex_lock(&srq->mutex);
 387                 ret = mthca_ARM_SRQ(dev, srq->srqn, attr->srq_limit, &status);
 388                 mutex_unlock(&srq->mutex);
 389
 390                 if (ret)
 391                         return ret;
 392                 if (status)
 393                         return -EINVAL;
 394         }
 395
 396         return 0;
 397 }
 398
 399 int mthca_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *srq_attr)
 400 {
 401         struct mthca_dev *dev = to_mdev(ibsrq->device);
 402         struct mthca_srq *srq = to_msrq(ibsrq);
 403         struct mthca_mailbox *mailbox;
 404         struct mthca_arbel_srq_context *arbel_ctx;
 405         struct mthca_tavor_srq_context *tavor_ctx;
 406         u8 status;
 407         int err;
 408
 409         mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
 410         if (IS_ERR(mailbox))
 411                 return PTR_ERR(mailbox);
 412
 413         err = mthca_QUERY_SRQ(dev, srq->srqn, mailbox, &status);
 414         if (err)
 415                 goto out;
 416
 417         if (mthca_is_memfree(dev)) {
 418                 arbel_ctx = mailbox->buf;
 419                 srq_attr->srq_limit = be16_to_cpu(arbel_ctx->limit_watermark);
 420         } else {
 421                 tavor_ctx = mailbox->buf;
 422                 srq_attr->srq_limit = be16_to_cpu(tavor_ctx->limit_watermark);
 423         }
 424
 425         srq_attr->max_wr  = srq->max - 1;
 426         srq_attr->max_sge = srq->max_gs;
 427
 428 out:
 429         mthca_free_mailbox(dev, mailbox);
 430
 431         return err;
 432 }
 433
 434 void mthca_srq_event(struct mthca_dev *dev, u32 srqn,
 435                      enum ib_event_type event_type)
 436 {
 437         struct mthca_srq *srq;
 438         struct ib_event event;
 439
 440         spin_lock(&dev->srq_table.lock);
 441         srq = mthca_array_get(&dev->srq_table.srq, srqn & (dev->limits.num_srqs - 1));
 442         if (srq)
 443                 ++srq->refcount;
 444         spin_unlock(&dev->srq_table.lock);
 445
 446         if (!srq) {
 447                 mthca_warn(dev, "Async event for bogus SRQ %08x\n", srqn);
 448                 return;
 449         }
 450
 451         if (!srq->ibsrq.event_handler)
 452                 goto out;
 453
 454         event.device      = &dev->ib_dev;
 455         event.event       = event_type;
 456         event.element.srq = &srq->ibsrq;
 457         srq->ibsrq.event_handler(&event, srq->ibsrq.srq_context);
 458
 459 out:
 460         spin_lock(&dev->srq_table.lock);
 461         if (!--srq->refcount)
 462                 wake_up(&srq->wait);
 463         spin_unlock(&dev->srq_table.lock);
 464 }
 465
 466 /*
 467  * This function must be called with IRQs disabled.
 468  */
 469 void mthca_free_srq_wqe(struct mthca_srq *srq, u32 wqe_addr)
 470 {
 471         int ind;
 472
 473         ind = wqe_addr >> srq->wqe_shift;
 474
 475         spin_lock(&srq->lock);
 476
 477         if (likely(srq->first_free >= 0))
 478                 *wqe_to_link(get_wqe(srq, srq->last_free)) = ind;
 479         else
 480                 srq->first_free = ind;
 481
 482         *wqe_to_link(get_wqe(srq, ind)) = -1;
 483         srq->last_free = ind;
 484
 485         spin_unlock(&srq->lock);
 486 }
 487
 488 int mthca_tavor_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
 489                               struct ib_recv_wr **bad_wr)
 490 {
 491         struct mthca_dev *dev = to_mdev(ibsrq->device);
 492         struct mthca_srq *srq = to_msrq(ibsrq);
 493         __be32 doorbell[2];
 494         unsigned long flags;
 495         int err = 0;
 496         int first_ind;
 497         int ind;
 498         int next_ind;
 499         int nreq;
 500         int i;
 501         void *wqe;
 502         void *prev_wqe;
 503
 504         spin_lock_irqsave(&srq->lock, flags);
 505
 506         first_ind = srq->first_free;
 507
 508         for (nreq = 0; wr; wr = wr->next) {
 509                 ind = srq->first_free;
 510
 511                 if (ind < 0) {
 512                         mthca_err(dev, "SRQ %06x full\n", srq->srqn);
 513                         err = -ENOMEM;
 514                         *bad_wr = wr;
 515                         break;
 516                 }
 517
 518                 wqe       = get_wqe(srq, ind);
 519                 next_ind  = *wqe_to_link(wqe);
 520
 521                 if (next_ind < 0) {
 522                         mthca_err(dev, "SRQ %06x full\n", srq->srqn);
 523                         err = -ENOMEM;
 524                         *bad_wr = wr;
 525                         break;
 526                 }
 527
 528                 prev_wqe  = srq->last;
 529                 srq->last = wqe;
 530
 531                 ((struct mthca_next_seg *) wqe)->nda_op = 0;
 532                 ((struct mthca_next_seg *) wqe)->ee_nds = 0;
 533                 /* flags field will always remain 0 */
 534
 535                 wqe += sizeof (struct mthca_next_seg);
 536
 537                 if (unlikely(wr->num_sge > srq->max_gs)) {
 538                         err = -EINVAL;
 539                         *bad_wr = wr;
 540                         srq->last = prev_wqe;
 541                         break;
 542                 }
 543
 544                 for (i = 0; i < wr->num_sge; ++i) {
 545                         ((struct mthca_data_seg *) wqe)->byte_count =
 546                                 cpu_to_be32(wr->sg_list[i].length);
 547                         ((struct mthca_data_seg *) wqe)->lkey =
 548                                 cpu_to_be32(wr->sg_list[i].lkey);
 549                         ((struct mthca_data_seg *) wqe)->addr =
 550                                 cpu_to_be64(wr->sg_list[i].addr);
 551                         wqe += sizeof (struct mthca_data_seg);
 552                 }
 553
 554                 if (i < srq->max_gs) {
 555                         ((struct mthca_data_seg *) wqe)->byte_count = 0;
 556                         ((struct mthca_data_seg *) wqe)->lkey = cpu_to_be32(MTHCA_INVAL_LKEY);
 557                         ((struct mthca_data_seg *) wqe)->addr = 0;
 558                 }
 559
 560                 ((struct mthca_next_seg *) prev_wqe)->nda_op =
 561                         cpu_to_be32((ind << srq->wqe_shift) | 1);
 562                 wmb();
 563                 ((struct mthca_next_seg *) prev_wqe)->ee_nds =
 564                         cpu_to_be32(MTHCA_NEXT_DBD);
 565
 566                 srq->wrid[ind]  = wr->wr_id;
 567                 srq->first_free = next_ind;
 568
 569                 ++nreq;
 570                 if (unlikely(nreq == MTHCA_TAVOR_MAX_WQES_PER_RECV_DB)) {
 571                         nreq = 0;
 572
 573                         doorbell[0] = cpu_to_be32(first_ind << srq->wqe_shift);
 574                         doorbell[1] = cpu_to_be32(srq->srqn << 8);
 575
 576                         /*
 577                          * Make sure that descriptors are written
 578                          * before doorbell is rung.
 579                          */
 580                         wmb();
 581
 582                         mthca_write64(doorbell,
 583                                       dev->kar + MTHCA_RECEIVE_DOORBELL,
 584                                       MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
 585
 586                         first_ind = srq->first_free;
 587                 }
 588         }
 589
 590         if (likely(nreq)) {
 591                 doorbell[0] = cpu_to_be32(first_ind << srq->wqe_shift);
 592                 doorbell[1] = cpu_to_be32((srq->srqn << 8) | nreq);
 593
 594                 /*
 595                  * Make sure that descriptors are written before
 596                  * doorbell is rung.
 597                  */
 598                 wmb();
 599
 600                 mthca_write64(doorbell,
 601                               dev->kar + MTHCA_RECEIVE_DOORBELL,
 602                               MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
 603         }
 604
 605         /*
 606          * Make sure doorbells don't leak out of SRQ spinlock and
 607          * reach the HCA out of order:
 608          */
 609         mmiowb();
 610
 611         spin_unlock_irqrestore(&srq->lock, flags);
 612         return err;
 613 }
 614
 615 int mthca_arbel_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
 616                               struct ib_recv_wr **bad_wr)
 617 {
 618         struct mthca_dev *dev = to_mdev(ibsrq->device);
 619         struct mthca_srq *srq = to_msrq(ibsrq);
 620         unsigned long flags;
 621         int err = 0;
 622         int ind;
 623         int next_ind;
 624         int nreq;
 625         int i;
 626         void *wqe;
 627
 628         spin_lock_irqsave(&srq->lock, flags);
 629
 630         for (nreq = 0; wr; ++nreq, wr = wr->next) {
 631                 ind = srq->first_free;
 632
 633                 if (ind < 0) {
 634                         mthca_err(dev, "SRQ %06x full\n", srq->srqn);
 635                         err = -ENOMEM;
 636                         *bad_wr = wr;
 637                         break;
 638                 }
 639
 640                 wqe       = get_wqe(srq, ind);
 641                 next_ind  = *wqe_to_link(wqe);
 642
 643                 if (next_ind < 0) {
 644                         mthca_err(dev, "SRQ %06x full\n", srq->srqn);
 645                         err = -ENOMEM;
 646                         *bad_wr = wr;
 647                         break;
 648                 }
 649
 650                 ((struct mthca_next_seg *) wqe)->nda_op =
 651                         cpu_to_be32((next_ind << srq->wqe_shift) | 1);
 652                 ((struct mthca_next_seg *) wqe)->ee_nds = 0;
 653                 /* flags field will always remain 0 */
 654
 655                 wqe += sizeof (struct mthca_next_seg);
 656
 657                 if (unlikely(wr->num_sge > srq->max_gs)) {
 658                         err = -EINVAL;
 659                         *bad_wr = wr;
 660                         break;
 661                 }
 662
 663                 for (i = 0; i < wr->num_sge; ++i) {
 664                         ((struct mthca_data_seg *) wqe)->byte_count =
 665                                 cpu_to_be32(wr->sg_list[i].length);
 666                         ((struct mthca_data_seg *) wqe)->lkey =
 667                                 cpu_to_be32(wr->sg_list[i].lkey);
 668                         ((struct mthca_data_seg *) wqe)->addr =
 669                                 cpu_to_be64(wr->sg_list[i].addr);
 670                         wqe += sizeof (struct mthca_data_seg);
 671                 }
 672
 673                 if (i < srq->max_gs) {
 674                         ((struct mthca_data_seg *) wqe)->byte_count = 0;
 675                         ((struct mthca_data_seg *) wqe)->lkey = cpu_to_be32(MTHCA_INVAL_LKEY);
 676                         ((struct mthca_data_seg *) wqe)->addr = 0;
 677                 }
 678
 679                 srq->wrid[ind]  = wr->wr_id;
 680                 srq->first_free = next_ind;
 681         }
 682
 683         if (likely(nreq)) {
 684                 srq->counter += nreq;
 685
 686                 /*
 687                  * Make sure that descriptors are written before
 688                  * we write doorbell record.
 689                  */
 690                 wmb();
 691                 *srq->db = cpu_to_be32(srq->counter);
 692         }
 693
 694         spin_unlock_irqrestore(&srq->lock, flags);
 695         return err;
 696 }
 697
 698 int mthca_max_srq_sge(struct mthca_dev *dev)
 699 {
 700         if (mthca_is_memfree(dev))
 701                 return dev->limits.max_sg;
 702
 703         /*
 704          * SRQ allocations are based on powers of 2 for Tavor,
 705          * (although they only need to be multiples of 16 bytes).
 706          *
 707          * Therefore, we need to base the max number of sg entries on
 708          * the largest power of 2 descriptor size that is <= to the
 709          * actual max WQE descriptor size, rather than return the
 710          * max_sg value given by the firmware (which is based on WQE
 711          * sizes as multiples of 16, not powers of 2).
 712          *
 713          * If SRQ implementation is changed for Tavor to be based on
 714          * multiples of 16, the calculation below can be deleted and
 715          * the FW max_sg value returned.
 716          */
 717         return min_t(int, dev->limits.max_sg,
 718                      ((1 << (fls(dev->limits.max_desc_sz) - 1)) -
 719                       sizeof (struct mthca_next_seg)) /
 720                      sizeof (struct mthca_data_seg));
 721 }
 722
 723 int mthca_init_srq_table(struct mthca_dev *dev)
 724 {
 725         int err;
 726
 727         if (!(dev->mthca_flags & MTHCA_FLAG_SRQ))
 728                 return 0;
 729
 730         spin_lock_init(&dev->srq_table.lock);
 731
 732         err = mthca_alloc_init(&dev->srq_table.alloc,
 733                                dev->limits.num_srqs,
 734                                dev->limits.num_srqs - 1,
 735                                dev->limits.reserved_srqs);
 736         if (err)
 737                 return err;
 738
 739         err = mthca_array_init(&dev->srq_table.srq,
 740                                dev->limits.num_srqs);
 741         if (err)
 742                 mthca_alloc_cleanup(&dev->srq_table.alloc);
 743
 744         return err;
 745 }
 746
 747 void mthca_cleanup_srq_table(struct mthca_dev *dev)
 748 {
 749         if (!(dev->mthca_flags & MTHCA_FLAG_SRQ))
 750                 return;
 751
 752         mthca_array_cleanup(&dev->srq_table.srq, dev->limits.num_srqs);
 753         mthca_alloc_cleanup(&dev->srq_table.alloc);
 754 }