drivers/infiniband/hw/mthca/mthca_memfree.c

   1 /*
   2  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
   3  * Copyright (c) 2005 Cisco Systems.  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  * $Id$
  34  */
  35
  36 #include <linux/mm.h>
  37
  38 #include "mthca_memfree.h"
  39 #include "mthca_dev.h"
  40 #include "mthca_cmd.h"
  41
  42 /*
  43  * We allocate in as big chunks as we can, up to a maximum of 256 KB
  44  * per chunk.
  45  */
  46 enum {
  47         MTHCA_ICM_ALLOC_SIZE   = 1 << 18,
  48         MTHCA_TABLE_CHUNK_SIZE = 1 << 18
  49 };
  50
  51 struct mthca_user_db_table {
  52         struct semaphore mutex;
  53         struct {
  54                 u64                uvirt;
  55                 struct scatterlist mem;
  56                 int                refcount;
  57         }                page[0];
  58 };
  59
  60 void mthca_free_icm(struct mthca_dev *dev, struct mthca_icm *icm)
  61 {
  62         struct mthca_icm_chunk *chunk, *tmp;
  63         int i;
  64
  65         if (!icm)
  66                 return;
  67
  68         list_for_each_entry_safe(chunk, tmp, &icm->chunk_list, list) {
  69                 if (chunk->nsg > 0)
  70                         pci_unmap_sg(dev->pdev, chunk->mem, chunk->npages,
  71                                      PCI_DMA_BIDIRECTIONAL);
  72
  73                 for (i = 0; i < chunk->npages; ++i)
  74                         __free_pages(chunk->mem[i].page,
  75                                      get_order(chunk->mem[i].length));
  76
  77                 kfree(chunk);
  78         }
  79
  80         kfree(icm);
  81 }
  82
  83 struct mthca_icm *mthca_alloc_icm(struct mthca_dev *dev, int npages,
  84                                   unsigned int gfp_mask)
  85 {
  86         struct mthca_icm *icm;
  87         struct mthca_icm_chunk *chunk = NULL;
  88         int cur_order;
  89
  90         icm = kmalloc(sizeof *icm, gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
  91         if (!icm)
  92                 return icm;
  93
  94         icm->refcount = 0;
  95         INIT_LIST_HEAD(&icm->chunk_list);
  96
  97         cur_order = get_order(MTHCA_ICM_ALLOC_SIZE);
  98
  99         while (npages > 0) {
 100                 if (!chunk) {
 101                         chunk = kmalloc(sizeof *chunk,
 102                                         gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
 103                         if (!chunk)
 104                                 goto fail;
 105
 106                         chunk->npages = 0;
 107                         chunk->nsg    = 0;
 108                         list_add_tail(&chunk->list, &icm->chunk_list);
 109                 }
 110
 111                 while (1 << cur_order > npages)
 112                         --cur_order;
 113
 114                 chunk->mem[chunk->npages].page = alloc_pages(gfp_mask, cur_order);
 115                 if (chunk->mem[chunk->npages].page) {
 116                         chunk->mem[chunk->npages].length = PAGE_SIZE << cur_order;
 117                         chunk->mem[chunk->npages].offset = 0;
 118
 119                         if (++chunk->npages == MTHCA_ICM_CHUNK_LEN) {
 120                                 chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
 121                                                         chunk->npages,
 122                                                         PCI_DMA_BIDIRECTIONAL);
 123
 124                                 if (chunk->nsg <= 0)
 125                                         goto fail;
 126
 127                                 chunk = NULL;
 128                         }
 129
 130                         npages -= 1 << cur_order;
 131                 } else {
 132                         --cur_order;
 133                         if (cur_order < 0)
 134                                 goto fail;
 135                 }
 136         }
 137
 138         if (chunk) {
 139                 chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
 140                                         chunk->npages,
 141                                         PCI_DMA_BIDIRECTIONAL);
 142
 143                 if (chunk->nsg <= 0)
 144                         goto fail;
 145         }
 146
 147         return icm;
 148
 149 fail:
 150         mthca_free_icm(dev, icm);
 151         return NULL;
 152 }
 153
 154 int mthca_table_get(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
 155 {
 156         int i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
 157         int ret = 0;
 158         u8 status;
 159
 160         down(&table->mutex);
 161
 162         if (table->icm[i]) {
 163                 ++table->icm[i]->refcount;
 164                 goto out;
 165         }
 166
 167         table->icm[i] = mthca_alloc_icm(dev, MTHCA_TABLE_CHUNK_SIZE >> PAGE_SHIFT,
 168                                         (table->lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
 169                                         __GFP_NOWARN);
 170         if (!table->icm[i]) {
 171                 ret = -ENOMEM;
 172                 goto out;
 173         }
 174
 175         if (mthca_MAP_ICM(dev, table->icm[i], table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 176                           &status) || status) {
 177                 mthca_free_icm(dev, table->icm[i]);
 178                 table->icm[i] = NULL;
 179                 ret = -ENOMEM;
 180                 goto out;
 181         }
 182
 183         ++table->icm[i]->refcount;
 184
 185 out:
 186         up(&table->mutex);
 187         return ret;
 188 }
 189
 190 void mthca_table_put(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
 191 {
 192         int i;
 193         u8 status;
 194
 195         if (!mthca_is_memfree(dev))
 196                 return;
 197
 198         i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
 199
 200         down(&table->mutex);
 201
 202         if (--table->icm[i]->refcount == 0) {
 203                 mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 204                                 MTHCA_TABLE_CHUNK_SIZE >> 12, &status);
 205                 mthca_free_icm(dev, table->icm[i]);
 206                 table->icm[i] = NULL;
 207         }
 208
 209         up(&table->mutex);
 210 }
 211
 212 void *mthca_table_find(struct mthca_icm_table *table, int obj)
 213 {
 214         int idx, offset, i;
 215         struct mthca_icm_chunk *chunk;
 216         struct mthca_icm *icm;
 217         struct page *page = NULL;
 218
 219         if (!table->lowmem)
 220                 return NULL;
 221
 222         down(&table->mutex);
 223
 224         idx = (obj & (table->num_obj - 1)) * table->obj_size;
 225         icm = table->icm[idx / MTHCA_TABLE_CHUNK_SIZE];
 226         offset = idx % MTHCA_TABLE_CHUNK_SIZE;
 227
 228         if (!icm)
 229                 goto out;
 230
 231         list_for_each_entry(chunk, &icm->chunk_list, list) {
 232                 for (i = 0; i < chunk->npages; ++i) {
 233                         if (chunk->mem[i].length >= offset) {
 234                                 page = chunk->mem[i].page;
 235                                 break;
 236                         }
 237                         offset -= chunk->mem[i].length;
 238                 }
 239         }
 240
 241 out:
 242         up(&table->mutex);
 243         return page ? lowmem_page_address(page) + offset : NULL;
 244 }
 245
 246 int mthca_table_get_range(struct mthca_dev *dev, struct mthca_icm_table *table,
 247                           int start, int end)
 248 {
 249         int inc = MTHCA_TABLE_CHUNK_SIZE / table->obj_size;
 250         int i, err;
 251
 252         for (i = start; i <= end; i += inc) {
 253                 err = mthca_table_get(dev, table, i);
 254                 if (err)
 255                         goto fail;
 256         }
 257
 258         return 0;
 259
 260 fail:
 261         while (i > start) {
 262                 i -= inc;
 263                 mthca_table_put(dev, table, i);
 264         }
 265
 266         return err;
 267 }
 268
 269 void mthca_table_put_range(struct mthca_dev *dev, struct mthca_icm_table *table,
 270                            int start, int end)
 271 {
 272         int i;
 273
 274         if (!mthca_is_memfree(dev))
 275                 return;
 276
 277         for (i = start; i <= end; i += MTHCA_TABLE_CHUNK_SIZE / table->obj_size)
 278                 mthca_table_put(dev, table, i);
 279 }
 280
 281 struct mthca_icm_table *mthca_alloc_icm_table(struct mthca_dev *dev,
 282                                               u64 virt, int obj_size,
 283                                               int nobj, int reserved,
 284                                               int use_lowmem)
 285 {
 286         struct mthca_icm_table *table;
 287         int num_icm;
 288         int i;
 289         u8 status;
 290
 291         num_icm = obj_size * nobj / MTHCA_TABLE_CHUNK_SIZE;
 292
 293         table = kmalloc(sizeof *table + num_icm * sizeof *table->icm, GFP_KERNEL);
 294         if (!table)
 295                 return NULL;
 296
 297         table->virt     = virt;
 298         table->num_icm  = num_icm;
 299         table->num_obj  = nobj;
 300         table->obj_size = obj_size;
 301         table->lowmem   = use_lowmem;
 302         init_MUTEX(&table->mutex);
 303
 304         for (i = 0; i < num_icm; ++i)
 305                 table->icm[i] = NULL;
 306
 307         for (i = 0; i * MTHCA_TABLE_CHUNK_SIZE < reserved * obj_size; ++i) {
 308                 table->icm[i] = mthca_alloc_icm(dev, MTHCA_TABLE_CHUNK_SIZE >> PAGE_SHIFT,
 309                                                 (use_lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
 310                                                 __GFP_NOWARN);
 311                 if (!table->icm[i])
 312                         goto err;
 313                 if (mthca_MAP_ICM(dev, table->icm[i], virt + i * MTHCA_TABLE_CHUNK_SIZE,
 314                                   &status) || status) {
 315                         mthca_free_icm(dev, table->icm[i]);
 316                         table->icm[i] = NULL;
 317                         goto err;
 318                 }
 319
 320                 /*
 321                  * Add a reference to this ICM chunk so that it never
 322                  * gets freed (since it contains reserved firmware objects).
 323                  */
 324                 ++table->icm[i]->refcount;
 325         }
 326
 327         return table;
 328
 329 err:
 330         for (i = 0; i < num_icm; ++i)
 331                 if (table->icm[i]) {
 332                         mthca_UNMAP_ICM(dev, virt + i * MTHCA_TABLE_CHUNK_SIZE,
 333                                         MTHCA_TABLE_CHUNK_SIZE >> 12, &status);
 334                         mthca_free_icm(dev, table->icm[i]);
 335                 }
 336
 337         kfree(table);
 338
 339         return NULL;
 340 }
 341
 342 void mthca_free_icm_table(struct mthca_dev *dev, struct mthca_icm_table *table)
 343 {
 344         int i;
 345         u8 status;
 346
 347         for (i = 0; i < table->num_icm; ++i)
 348                 if (table->icm[i]) {
 349                         mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 350                                         MTHCA_TABLE_CHUNK_SIZE >> 12, &status);
 351                         mthca_free_icm(dev, table->icm[i]);
 352                 }
 353
 354         kfree(table);
 355 }
 356
 357 static u64 mthca_uarc_virt(struct mthca_dev *dev, struct mthca_uar *uar, int page)
 358 {
 359         return dev->uar_table.uarc_base +
 360                 uar->index * dev->uar_table.uarc_size +
 361                 page * 4096;
 362 }
 363
 364 int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
 365                       struct mthca_user_db_table *db_tab, int index, u64 uaddr)
 366 {
 367         int ret = 0;
 368         u8 status;
 369         int i;
 370
 371         if (!mthca_is_memfree(dev))
 372                 return 0;
 373
 374         if (index < 0 || index > dev->uar_table.uarc_size / 8)
 375                 return -EINVAL;
 376
 377         down(&db_tab->mutex);
 378
 379         i = index / MTHCA_DB_REC_PER_PAGE;
 380
 381         if ((db_tab->page[i].refcount >= MTHCA_DB_REC_PER_PAGE)       ||
 382             (db_tab->page[i].uvirt && db_tab->page[i].uvirt != uaddr) ||
 383             (uaddr & 4095)) {
 384                 ret = -EINVAL;
 385                 goto out;
 386         }
 387
 388         if (db_tab->page[i].refcount) {
 389                 ++db_tab->page[i].refcount;
 390                 goto out;
 391         }
 392
 393         ret = get_user_pages(current, current->mm, uaddr & PAGE_MASK, 1, 1, 0,
 394                              &db_tab->page[i].mem.page, NULL);
 395         if (ret < 0)
 396                 goto out;
 397
 398         db_tab->page[i].mem.length = 4096;
 399         db_tab->page[i].mem.offset = uaddr & ~PAGE_MASK;
 400
 401         ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 402         if (ret < 0) {
 403                 put_page(db_tab->page[i].mem.page);
 404                 goto out;
 405         }
 406
 407         ret = mthca_MAP_ICM_page(dev, sg_dma_address(&db_tab->page[i].mem),
 408                                  mthca_uarc_virt(dev, uar, i), &status);
 409         if (!ret && status)
 410                 ret = -EINVAL;
 411         if (ret) {
 412                 pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 413                 put_page(db_tab->page[i].mem.page);
 414                 goto out;
 415         }
 416
 417         db_tab->page[i].uvirt    = uaddr;
 418         db_tab->page[i].refcount = 1;
 419
 420 out:
 421         up(&db_tab->mutex);
 422         return ret;
 423 }
 424
 425 void mthca_unmap_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
 426                          struct mthca_user_db_table *db_tab, int index)
 427 {
 428         if (!mthca_is_memfree(dev))
 429                 return;
 430
 431         /*
 432          * To make our bookkeeping simpler, we don't unmap DB
 433          * pages until we clean up the whole db table.
 434          */
 435
 436         down(&db_tab->mutex);
 437
 438         --db_tab->page[index / MTHCA_DB_REC_PER_PAGE].refcount;
 439
 440         up(&db_tab->mutex);
 441 }
 442
 443 struct mthca_user_db_table *mthca_init_user_db_tab(struct mthca_dev *dev)
 444 {
 445         struct mthca_user_db_table *db_tab;
 446         int npages;
 447         int i;
 448
 449         if (!mthca_is_memfree(dev))
 450                 return NULL;
 451
 452         npages = dev->uar_table.uarc_size / 4096;
 453         db_tab = kmalloc(sizeof *db_tab + npages * sizeof *db_tab->page, GFP_KERNEL);
 454         if (!db_tab)
 455                 return ERR_PTR(-ENOMEM);
 456
 457         init_MUTEX(&db_tab->mutex);
 458         for (i = 0; i < npages; ++i) {
 459                 db_tab->page[i].refcount = 0;
 460                 db_tab->page[i].uvirt    = 0;
 461         }
 462
 463         return db_tab;
 464 }
 465
 466 void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
 467                                struct mthca_user_db_table *db_tab)
 468 {
 469         int i;
 470         u8 status;
 471
 472         if (!mthca_is_memfree(dev))
 473                 return;
 474
 475         for (i = 0; i < dev->uar_table.uarc_size / 4096; ++i) {
 476                 if (db_tab->page[i].uvirt) {
 477                         mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, uar, i), 1, &status);
 478                         pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 479                         put_page(db_tab->page[i].mem.page);
 480                 }
 481         }
 482 }
 483
 484 int mthca_alloc_db(struct mthca_dev *dev, int type, u32 qn, u32 **db)
 485 {
 486         int group;
 487         int start, end, dir;
 488         int i, j;
 489         struct mthca_db_page *page;
 490         int ret = 0;
 491         u8 status;
 492
 493         down(&dev->db_tab->mutex);
 494
 495         switch (type) {
 496         case MTHCA_DB_TYPE_CQ_ARM:
 497         case MTHCA_DB_TYPE_SQ:
 498                 group = 0;
 499                 start = 0;
 500                 end   = dev->db_tab->max_group1;
 501                 dir   = 1;
 502                 break;
 503
 504         case MTHCA_DB_TYPE_CQ_SET_CI:
 505         case MTHCA_DB_TYPE_RQ:
 506         case MTHCA_DB_TYPE_SRQ:
 507                 group = 1;
 508                 start = dev->db_tab->npages - 1;
 509                 end   = dev->db_tab->min_group2;
 510                 dir   = -1;
 511                 break;
 512
 513         default:
 514                 ret = -EINVAL;
 515                 goto out;
 516         }
 517
 518         for (i = start; i != end; i += dir)
 519                 if (dev->db_tab->page[i].db_rec &&
 520                     !bitmap_full(dev->db_tab->page[i].used,
 521                                  MTHCA_DB_REC_PER_PAGE)) {
 522                         page = dev->db_tab->page + i;
 523                         goto found;
 524                 }
 525
 526         if (dev->db_tab->max_group1 >= dev->db_tab->min_group2 - 1) {
 527                 ret = -ENOMEM;
 528                 goto out;
 529         }
 530
 531         page = dev->db_tab->page + end;
 532         page->db_rec = dma_alloc_coherent(&dev->pdev->dev, 4096,
 533                                           &page->mapping, GFP_KERNEL);
 534         if (!page->db_rec) {
 535                 ret = -ENOMEM;
 536                 goto out;
 537         }
 538         memset(page->db_rec, 0, 4096);
 539
 540         ret = mthca_MAP_ICM_page(dev, page->mapping,
 541                                  mthca_uarc_virt(dev, &dev->driver_uar, i), &status);
 542         if (!ret && status)
 543                 ret = -EINVAL;
 544         if (ret) {
 545                 dma_free_coherent(&dev->pdev->dev, 4096,
 546                                   page->db_rec, page->mapping);
 547                 goto out;
 548         }
 549
 550         bitmap_zero(page->used, MTHCA_DB_REC_PER_PAGE);
 551         if (group == 0)
 552                 ++dev->db_tab->max_group1;
 553         else
 554                 --dev->db_tab->min_group2;
 555
 556 found:
 557         j = find_first_zero_bit(page->used, MTHCA_DB_REC_PER_PAGE);
 558         set_bit(j, page->used);
 559
 560         if (group == 1)
 561                 j = MTHCA_DB_REC_PER_PAGE - 1 - j;
 562
 563         ret = i * MTHCA_DB_REC_PER_PAGE + j;
 564
 565         page->db_rec[j] = cpu_to_be64((qn << 8) | (type << 5));
 566
 567         *db = (u32 *) &page->db_rec[j];
 568
 569 out:
 570         up(&dev->db_tab->mutex);
 571
 572         return ret;
 573 }
 574
 575 void mthca_free_db(struct mthca_dev *dev, int type, int db_index)
 576 {
 577         int i, j;
 578         struct mthca_db_page *page;
 579         u8 status;
 580
 581         i = db_index / MTHCA_DB_REC_PER_PAGE;
 582         j = db_index % MTHCA_DB_REC_PER_PAGE;
 583
 584         page = dev->db_tab->page + i;
 585
 586         down(&dev->db_tab->mutex);
 587
 588         page->db_rec[j] = 0;
 589         if (i >= dev->db_tab->min_group2)
 590                 j = MTHCA_DB_REC_PER_PAGE - 1 - j;
 591         clear_bit(j, page->used);
 592
 593         if (bitmap_empty(page->used, MTHCA_DB_REC_PER_PAGE) &&
 594             i >= dev->db_tab->max_group1 - 1) {
 595                 mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 596
 597                 dma_free_coherent(&dev->pdev->dev, 4096,
 598                                   page->db_rec, page->mapping);
 599                 page->db_rec = NULL;
 600
 601                 if (i == dev->db_tab->max_group1) {
 602                         --dev->db_tab->max_group1;
 603                         /* XXX may be able to unmap more pages now */
 604                 }
 605                 if (i == dev->db_tab->min_group2)
 606                         ++dev->db_tab->min_group2;
 607         }
 608
 609         up(&dev->db_tab->mutex);
 610 }
 611
 612 int mthca_init_db_tab(struct mthca_dev *dev)
 613 {
 614         int i;
 615
 616         if (!mthca_is_memfree(dev))
 617                 return 0;
 618
 619         dev->db_tab = kmalloc(sizeof *dev->db_tab, GFP_KERNEL);
 620         if (!dev->db_tab)
 621                 return -ENOMEM;
 622
 623         init_MUTEX(&dev->db_tab->mutex);
 624
 625         dev->db_tab->npages     = dev->uar_table.uarc_size / 4096;
 626         dev->db_tab->max_group1 = 0;
 627         dev->db_tab->min_group2 = dev->db_tab->npages - 1;
 628
 629         dev->db_tab->page = kmalloc(dev->db_tab->npages *
 630                                     sizeof *dev->db_tab->page,
 631                                     GFP_KERNEL);
 632         if (!dev->db_tab->page) {
 633                 kfree(dev->db_tab);
 634                 return -ENOMEM;
 635         }
 636
 637         for (i = 0; i < dev->db_tab->npages; ++i)
 638                 dev->db_tab->page[i].db_rec = NULL;
 639
 640         return 0;
 641 }
 642
 643 void mthca_cleanup_db_tab(struct mthca_dev *dev)
 644 {
 645         int i;
 646         u8 status;
 647
 648         if (!mthca_is_memfree(dev))
 649                 return;
 650
 651         /*
 652          * Because we don't always free our UARC pages when they
 653          * become empty to make mthca_free_db() simpler we need to
 654          * make a sweep through the doorbell pages and free any
 655          * leftover pages now.
 656          */
 657         for (i = 0; i < dev->db_tab->npages; ++i) {
 658                 if (!dev->db_tab->page[i].db_rec)
 659                         continue;
 660
 661                 if (!bitmap_empty(dev->db_tab->page[i].used, MTHCA_DB_REC_PER_PAGE))
 662                         mthca_warn(dev, "Kernel UARC page %d not empty\n", i);
 663
 664                 mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 665
 666                 dma_free_coherent(&dev->pdev->dev, 4096,
 667                                   dev->db_tab->page[i].db_rec,
 668                                   dev->db_tab->page[i].mapping);
 669         }
 670
 671         kfree(dev->db_tab->page);
 672         kfree(dev->db_tab);
 673 }