LXR linux/drivers/infiniband/hw/mthca/mthca

   1/*
   2 * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
   3 * Copyright (c) 2005 Cisco Systems.  All rights reserved.
   4 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
   5 *
   6 * This software is available to you under a choice of one of two
   7 * licenses.  You may choose to be licensed under the terms of the GNU
   8 * General Public License (GPL) Version 2, available from the file
   9 * COPYING in the main directory of this source tree, or the
  10 * OpenIB.org BSD license below:
  11 *
  12 *     Redistribution and use in source and binary forms, with or
  13 *     without modification, are permitted provided that the following
  14 *     conditions are met:
  15 *
  16 *      - Redistributions of source code must retain the above
  17 *        copyright notice, this list of conditions and the following
  18 *        disclaimer.
  19 *
  20 *      - Redistributions in binary form must reproduce the above
  21 *        copyright notice, this list of conditions and the following
  22 *        disclaimer in the documentation and/or other materials
  23 *        provided with the distribution.
  24 *
  25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32 * SOFTWARE.
  33 *
  34 * $Id$
  35 */
  36
  37#include <linux/mm.h>
  38
  39#include "mthca_memfree.h"
  40#include "mthca_dev.h"
  41#include "mthca_cmd.h"
  42
  43/*
  44 * We allocate in as big chunks as we can, up to a maximum of 256 KB
  45 * per chunk.
  46 */
  47enum {
  48        MTHCA_ICM_ALLOC_SIZE   = 1 << 18,
  49        MTHCA_TABLE_CHUNK_SIZE = 1 << 18
  50};
  51
  52struct mthca_user_db_table {
  53        struct mutex mutex;
  54        struct {
  55                u64                uvirt;
  56                struct scatterlist mem;
  57                int                refcount;
  58        }                page[0];
  59};
  60
  61void mthca_free_icm(struct mthca_dev *dev, struct mthca_icm *icm)
  62{
  63        struct mthca_icm_chunk *chunk, *tmp;
  64        int i;
  65
  66        if (!icm)
  67                return;
  68
  69        list_for_each_entry_safe(chunk, tmp, &icm->chunk_list, list) {
  70                if (chunk->nsg > 0)
  71                        pci_unmap_sg(dev->pdev, chunk->mem, chunk->npages,
  72                                     PCI_DMA_BIDIRECTIONAL);
  73
  74                for (i = 0; i < chunk->npages; ++i)
  75                        __free_pages(chunk->mem[i].page,
  76                                     get_order(chunk->mem[i].length));
  77
  78                kfree(chunk);
  79        }
  80
  81        kfree(icm);
  82}
  83
  84struct mthca_icm *mthca_alloc_icm(struct mthca_dev *dev, int npages,
  85                                  gfp_t gfp_mask)
  86{
  87        struct mthca_icm *icm;
  88        struct mthca_icm_chunk *chunk = NULL;
  89        int cur_order;
  90
  91        icm = kmalloc(sizeof *icm, gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
  92        if (!icm)
  93                return icm;
  94
  95        icm->refcount = 0;
  96        INIT_LIST_HEAD(&icm->chunk_list);
  97
  98        cur_order = get_order(MTHCA_ICM_ALLOC_SIZE);
  99
 100        while (npages > 0) {
 101                if (!chunk) {
 102                        chunk = kmalloc(sizeof *chunk,
 103                                        gfp_mask & ~(__GFP_HIGHMEM | __GFP_NOWARN));
 104                        if (!chunk)
 105                                goto fail;
 106
 107                        chunk->npages = 0;
 108                        chunk->nsg    = 0;
 109                        list_add_tail(&chunk->list, &icm->chunk_list);
 110                }
 111
 112                while (1 << cur_order > npages)
 113                        --cur_order;
 114
 115                chunk->mem[chunk->npages].page = alloc_pages(gfp_mask, cur_order);
 116                if (chunk->mem[chunk->npages].page) {
 117                        chunk->mem[chunk->npages].length = PAGE_SIZE << cur_order;
 118                        chunk->mem[chunk->npages].offset = 0;
 119
 120                        if (++chunk->npages == MTHCA_ICM_CHUNK_LEN) {
 121                                chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
 122                                                        chunk->npages,
 123                                                        PCI_DMA_BIDIRECTIONAL);
 124
 125                                if (chunk->nsg <= 0)
 126                                        goto fail;
 127
 128                                chunk = NULL;
 129                        }
 130
 131                        npages -= 1 << cur_order;
 132                } else {
 133                        --cur_order;
 134                        if (cur_order < 0)
 135                                goto fail;
 136                }
 137        }
 138
 139        if (chunk) {
 140                chunk->nsg = pci_map_sg(dev->pdev, chunk->mem,
 141                                        chunk->npages,
 142                                        PCI_DMA_BIDIRECTIONAL);
 143
 144                if (chunk->nsg <= 0)
 145                        goto fail;
 146        }
 147
 148        return icm;
 149
 150fail:
 151        mthca_free_icm(dev, icm);
 152        return NULL;
 153}
 154
 155int mthca_table_get(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
 156{
 157        int i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
 158        int ret = 0;
 159        u8 status;
 160
 161        mutex_lock(&table->mutex);
 162
 163        if (table->icm[i]) {
 164                ++table->icm[i]->refcount;
 165                goto out;
 166        }
 167
 168        table->icm[i] = mthca_alloc_icm(dev, MTHCA_TABLE_CHUNK_SIZE >> PAGE_SHIFT,
 169                                        (table->lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
 170                                        __GFP_NOWARN);
 171        if (!table->icm[i]) {
 172                ret = -ENOMEM;
 173                goto out;
 174        }
 175
 176        if (mthca_MAP_ICM(dev, table->icm[i], table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 177                          &status) || status) {
 178                mthca_free_icm(dev, table->icm[i]);
 179                table->icm[i] = NULL;
 180                ret = -ENOMEM;
 181                goto out;
 182        }
 183
 184        ++table->icm[i]->refcount;
 185
 186out:
 187        mutex_unlock(&table->mutex);
 188        return ret;
 189}
 190
 191void mthca_table_put(struct mthca_dev *dev, struct mthca_icm_table *table, int obj)
 192{
 193        int i;
 194        u8 status;
 195
 196        if (!mthca_is_memfree(dev))
 197                return;
 198
 199        i = (obj & (table->num_obj - 1)) * table->obj_size / MTHCA_TABLE_CHUNK_SIZE;
 200
 201        mutex_lock(&table->mutex);
 202
 203        if (--table->icm[i]->refcount == 0) {
 204                mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 205                                MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
 206                                &status);
 207                mthca_free_icm(dev, table->icm[i]);
 208                table->icm[i] = NULL;
 209        }
 210
 211        mutex_unlock(&table->mutex);
 212}
 213
 214void *mthca_table_find(struct mthca_icm_table *table, int obj)
 215{
 216        int idx, offset, i;
 217        struct mthca_icm_chunk *chunk;
 218        struct mthca_icm *icm;
 219        struct page *page = NULL;
 220
 221        if (!table->lowmem)
 222                return NULL;
 223
 224        mutex_lock(&table->mutex);
 225
 226        idx = (obj & (table->num_obj - 1)) * table->obj_size;
 227        icm = table->icm[idx / MTHCA_TABLE_CHUNK_SIZE];
 228        offset = idx % MTHCA_TABLE_CHUNK_SIZE;
 229
 230        if (!icm)
 231                goto out;
 232
 233        list_for_each_entry(chunk, &icm->chunk_list, list) {
 234                for (i = 0; i < chunk->npages; ++i) {
 235                        if (chunk->mem[i].length >= offset) {
 236                                page = chunk->mem[i].page;
 237                                goto out;
 238                        }
 239                        offset -= chunk->mem[i].length;
 240                }
 241        }
 242
 243out:
 244        mutex_unlock(&table->mutex);
 245        return page ? lowmem_page_address(page) + offset : NULL;
 246}
 247
 248int mthca_table_get_range(struct mthca_dev *dev, struct mthca_icm_table *table,
 249                          int start, int end)
 250{
 251        int inc = MTHCA_TABLE_CHUNK_SIZE / table->obj_size;
 252        int i, err;
 253
 254        for (i = start; i <= end; i += inc) {
 255                err = mthca_table_get(dev, table, i);
 256                if (err)
 257                        goto fail;
 258        }
 259
 260        return 0;
 261
 262fail:
 263        while (i > start) {
 264                i -= inc;
 265                mthca_table_put(dev, table, i);
 266        }
 267
 268        return err;
 269}
 270
 271void mthca_table_put_range(struct mthca_dev *dev, struct mthca_icm_table *table,
 272                           int start, int end)
 273{
 274        int i;
 275
 276        if (!mthca_is_memfree(dev))
 277                return;
 278
 279        for (i = start; i <= end; i += MTHCA_TABLE_CHUNK_SIZE / table->obj_size)
 280                mthca_table_put(dev, table, i);
 281}
 282
 283struct mthca_icm_table *mthca_alloc_icm_table(struct mthca_dev *dev,
 284                                              u64 virt, int obj_size,
 285                                              int nobj, int reserved,
 286                                              int use_lowmem)
 287{
 288        struct mthca_icm_table *table;
 289        int num_icm;
 290        unsigned chunk_size;
 291        int i;
 292        u8 status;
 293
 294        num_icm = (obj_size * nobj + MTHCA_TABLE_CHUNK_SIZE - 1) / MTHCA_TABLE_CHUNK_SIZE;
 295
 296        table = kmalloc(sizeof *table + num_icm * sizeof *table->icm, GFP_KERNEL);
 297        if (!table)
 298                return NULL;
 299
 300        table->virt     = virt;
 301        table->num_icm  = num_icm;
 302        table->num_obj  = nobj;
 303        table->obj_size = obj_size;
 304        table->lowmem   = use_lowmem;
 305        mutex_init(&table->mutex);
 306
 307        for (i = 0; i < num_icm; ++i)
 308                table->icm[i] = NULL;
 309
 310        for (i = 0; i * MTHCA_TABLE_CHUNK_SIZE < reserved * obj_size; ++i) {
 311                chunk_size = MTHCA_TABLE_CHUNK_SIZE;
 312                if ((i + 1) * MTHCA_TABLE_CHUNK_SIZE > nobj * obj_size)
 313                        chunk_size = nobj * obj_size - i * MTHCA_TABLE_CHUNK_SIZE;
 314
 315                table->icm[i] = mthca_alloc_icm(dev, chunk_size >> PAGE_SHIFT,
 316                                                (use_lowmem ? GFP_KERNEL : GFP_HIGHUSER) |
 317                                                __GFP_NOWARN);
 318                if (!table->icm[i])
 319                        goto err;
 320                if (mthca_MAP_ICM(dev, table->icm[i], virt + i * MTHCA_TABLE_CHUNK_SIZE,
 321                                  &status) || status) {
 322                        mthca_free_icm(dev, table->icm[i]);
 323                        table->icm[i] = NULL;
 324                        goto err;
 325                }
 326
 327                /*
 328                 * Add a reference to this ICM chunk so that it never
 329                 * gets freed (since it contains reserved firmware objects).
 330                 */
 331                ++table->icm[i]->refcount;
 332        }
 333
 334        return table;
 335
 336err:
 337        for (i = 0; i < num_icm; ++i)
 338                if (table->icm[i]) {
 339                        mthca_UNMAP_ICM(dev, virt + i * MTHCA_TABLE_CHUNK_SIZE,
 340                                        MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
 341                                        &status);
 342                        mthca_free_icm(dev, table->icm[i]);
 343                }
 344
 345        kfree(table);
 346
 347        return NULL;
 348}
 349
 350void mthca_free_icm_table(struct mthca_dev *dev, struct mthca_icm_table *table)
 351{
 352        int i;
 353        u8 status;
 354
 355        for (i = 0; i < table->num_icm; ++i)
 356                if (table->icm[i]) {
 357                        mthca_UNMAP_ICM(dev, table->virt + i * MTHCA_TABLE_CHUNK_SIZE,
 358                                        MTHCA_TABLE_CHUNK_SIZE / MTHCA_ICM_PAGE_SIZE,
 359                                        &status);
 360                        mthca_free_icm(dev, table->icm[i]);
 361                }
 362
 363        kfree(table);
 364}
 365
 366static u64 mthca_uarc_virt(struct mthca_dev *dev, struct mthca_uar *uar, int page)
 367{
 368        return dev->uar_table.uarc_base +
 369                uar->index * dev->uar_table.uarc_size +
 370                page * MTHCA_ICM_PAGE_SIZE;
 371}
 372
 373int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
 374                      struct mthca_user_db_table *db_tab, int index, u64 uaddr)
 375{
 376        int ret = 0;
 377        u8 status;
 378        int i;
 379
 380        if (!mthca_is_memfree(dev))
 381                return 0;
 382
 383        if (index < 0 || index > dev->uar_table.uarc_size / 8)
 384                return -EINVAL;
 385
 386        mutex_lock(&db_tab->mutex);
 387
 388        i = index / MTHCA_DB_REC_PER_PAGE;
 389
 390        if ((db_tab->page[i].refcount >= MTHCA_DB_REC_PER_PAGE)       ||
 391            (db_tab->page[i].uvirt && db_tab->page[i].uvirt != uaddr) ||
 392            (uaddr & 4095)) {
 393                ret = -EINVAL;
 394                goto out;
 395        }
 396
 397        if (db_tab->page[i].refcount) {
 398                ++db_tab->page[i].refcount;
 399                goto out;
 400        }
 401
 402        ret = get_user_pages(current, current->mm, uaddr & PAGE_MASK, 1, 1, 0,
 403                             &db_tab->page[i].mem.page, NULL);
 404        if (ret < 0)
 405                goto out;
 406
 407        db_tab->page[i].mem.length = MTHCA_ICM_PAGE_SIZE;
 408        db_tab->page[i].mem.offset = uaddr & ~PAGE_MASK;
 409
 410        ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 411        if (ret < 0) {
 412                put_page(db_tab->page[i].mem.page);
 413                goto out;
 414        }
 415
 416        ret = mthca_MAP_ICM_page(dev, sg_dma_address(&db_tab->page[i].mem),
 417                                 mthca_uarc_virt(dev, uar, i), &status);
 418        if (!ret && status)
 419                ret = -EINVAL;
 420        if (ret) {
 421                pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 422                put_page(db_tab->page[i].mem.page);
 423                goto out;
 424        }
 425
 426        db_tab->page[i].uvirt    = uaddr;
 427        db_tab->page[i].refcount = 1;
 428
 429out:
 430        mutex_unlock(&db_tab->mutex);
 431        return ret;
 432}
 433
 434void mthca_unmap_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
 435                         struct mthca_user_db_table *db_tab, int index)
 436{
 437        if (!mthca_is_memfree(dev))
 438                return;
 439
 440        /*
 441         * To make our bookkeeping simpler, we don't unmap DB
 442         * pages until we clean up the whole db table.
 443         */
 444
 445        mutex_lock(&db_tab->mutex);
 446
 447        --db_tab->page[index / MTHCA_DB_REC_PER_PAGE].refcount;
 448
 449        mutex_unlock(&db_tab->mutex);
 450}
 451
 452struct mthca_user_db_table *mthca_init_user_db_tab(struct mthca_dev *dev)
 453{
 454        struct mthca_user_db_table *db_tab;
 455        int npages;
 456        int i;
 457
 458        if (!mthca_is_memfree(dev))
 459                return NULL;
 460
 461        npages = dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE;
 462        db_tab = kmalloc(sizeof *db_tab + npages * sizeof *db_tab->page, GFP_KERNEL);
 463        if (!db_tab)
 464                return ERR_PTR(-ENOMEM);
 465
 466        mutex_init(&db_tab->mutex);
 467        for (i = 0; i < npages; ++i) {
 468                db_tab->page[i].refcount = 0;
 469                db_tab->page[i].uvirt    = 0;
 470        }
 471
 472        return db_tab;
 473}
 474
 475void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
 476                               struct mthca_user_db_table *db_tab)
 477{
 478        int i;
 479        u8 status;
 480
 481        if (!mthca_is_memfree(dev))
 482                return;
 483
 484        for (i = 0; i < dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE; ++i) {
 485                if (db_tab->page[i].uvirt) {
 486                        mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, uar, i), 1, &status);
 487                        pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
 488                        put_page(db_tab->page[i].mem.page);
 489                }
 490        }
 491
 492        kfree(db_tab);
 493}
 494
 495int mthca_alloc_db(struct mthca_dev *dev, enum mthca_db_type type,
 496                   u32 qn, __be32 **db)
 497{
 498        int group;
 499        int start, end, dir;
 500        int i, j;
 501        struct mthca_db_page *page;
 502        int ret = 0;
 503        u8 status;
 504
 505        mutex_lock(&dev->db_tab->mutex);
 506
 507        switch (type) {
 508        case MTHCA_DB_TYPE_CQ_ARM:
 509        case MTHCA_DB_TYPE_SQ:
 510                group = 0;
 511                start = 0;
 512                end   = dev->db_tab->max_group1;
 513                dir   = 1;
 514                break;
 515
 516        case MTHCA_DB_TYPE_CQ_SET_CI:
 517        case MTHCA_DB_TYPE_RQ:
 518        case MTHCA_DB_TYPE_SRQ:
 519                group = 1;
 520                start = dev->db_tab->npages - 1;
 521                end   = dev->db_tab->min_group2;
 522                dir   = -1;
 523                break;
 524
 525        default:
 526                ret = -EINVAL;
 527                goto out;
 528        }
 529
 530        for (i = start; i != end; i += dir)
 531                if (dev->db_tab->page[i].db_rec &&
 532                    !bitmap_full(dev->db_tab->page[i].used,
 533                                 MTHCA_DB_REC_PER_PAGE)) {
 534                        page = dev->db_tab->page + i;
 535                        goto found;
 536                }
 537
 538        for (i = start; i != end; i += dir)
 539                if (!dev->db_tab->page[i].db_rec) {
 540                        page = dev->db_tab->page + i;
 541                        goto alloc;
 542                }
 543
 544        if (dev->db_tab->max_group1 >= dev->db_tab->min_group2 - 1) {
 545                ret = -ENOMEM;
 546                goto out;
 547        }
 548
 549        if (group == 0)
 550                ++dev->db_tab->max_group1;
 551        else
 552                --dev->db_tab->min_group2;
 553
 554        page = dev->db_tab->page + end;
 555
 556alloc:
 557        page->db_rec = dma_alloc_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
 558                                          &page->mapping, GFP_KERNEL);
 559        if (!page->db_rec) {
 560                ret = -ENOMEM;
 561                goto out;
 562        }
 563        memset(page->db_rec, 0, MTHCA_ICM_PAGE_SIZE);
 564
 565        ret = mthca_MAP_ICM_page(dev, page->mapping,
 566                                 mthca_uarc_virt(dev, &dev->driver_uar, i), &status);
 567        if (!ret && status)
 568                ret = -EINVAL;
 569        if (ret) {
 570                dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
 571                                  page->db_rec, page->mapping);
 572                goto out;
 573        }
 574
 575        bitmap_zero(page->used, MTHCA_DB_REC_PER_PAGE);
 576
 577found:
 578        j = find_first_zero_bit(page->used, MTHCA_DB_REC_PER_PAGE);
 579        set_bit(j, page->used);
 580
 581        if (group == 1)
 582                j = MTHCA_DB_REC_PER_PAGE - 1 - j;
 583
 584        ret = i * MTHCA_DB_REC_PER_PAGE + j;
 585
 586        page->db_rec[j] = cpu_to_be64((qn << 8) | (type << 5));
 587
 588        *db = (__be32 *) &page->db_rec[j];
 589
 590out:
 591        mutex_unlock(&dev->db_tab->mutex);
 592
 593        return ret;
 594}
 595
 596void mthca_free_db(struct mthca_dev *dev, int type, int db_index)
 597{
 598        int i, j;
 599        struct mthca_db_page *page;
 600        u8 status;
 601
 602        i = db_index / MTHCA_DB_REC_PER_PAGE;
 603        j = db_index % MTHCA_DB_REC_PER_PAGE;
 604
 605        page = dev->db_tab->page + i;
 606
 607        mutex_lock(&dev->db_tab->mutex);
 608
 609        page->db_rec[j] = 0;
 610        if (i >= dev->db_tab->min_group2)
 611                j = MTHCA_DB_REC_PER_PAGE - 1 - j;
 612        clear_bit(j, page->used);
 613
 614        if (bitmap_empty(page->used, MTHCA_DB_REC_PER_PAGE) &&
 615            i >= dev->db_tab->max_group1 - 1) {
 616                mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 617
 618                dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
 619                                  page->db_rec, page->mapping);
 620                page->db_rec = NULL;
 621
 622                if (i == dev->db_tab->max_group1) {
 623                        --dev->db_tab->max_group1;
 624                        /* XXX may be able to unmap more pages now */
 625                }
 626                if (i == dev->db_tab->min_group2)
 627                        ++dev->db_tab->min_group2;
 628        }
 629
 630        mutex_unlock(&dev->db_tab->mutex);
 631}
 632
 633int mthca_init_db_tab(struct mthca_dev *dev)
 634{
 635        int i;
 636
 637        if (!mthca_is_memfree(dev))
 638                return 0;
 639
 640        dev->db_tab = kmalloc(sizeof *dev->db_tab, GFP_KERNEL);
 641        if (!dev->db_tab)
 642                return -ENOMEM;
 643
 644        mutex_init(&dev->db_tab->mutex);
 645
 646        dev->db_tab->npages     = dev->uar_table.uarc_size / MTHCA_ICM_PAGE_SIZE;
 647        dev->db_tab->max_group1 = 0;
 648        dev->db_tab->min_group2 = dev->db_tab->npages - 1;
 649
 650        dev->db_tab->page = kmalloc(dev->db_tab->npages *
 651                                    sizeof *dev->db_tab->page,
 652                                    GFP_KERNEL);
 653        if (!dev->db_tab->page) {
 654                kfree(dev->db_tab);
 655                return -ENOMEM;
 656        }
 657
 658        for (i = 0; i < dev->db_tab->npages; ++i)
 659                dev->db_tab->page[i].db_rec = NULL;
 660
 661        return 0;
 662}
 663
 664void mthca_cleanup_db_tab(struct mthca_dev *dev)
 665{
 666        int i;
 667        u8 status;
 668
 669        if (!mthca_is_memfree(dev))
 670                return;
 671
 672        /*
 673         * Because we don't always free our UARC pages when they
 674         * become empty to make mthca_free_db() simpler we need to
 675         * make a sweep through the doorbell pages and free any
 676         * leftover pages now.
 677         */
 678        for (i = 0; i < dev->db_tab->npages; ++i) {
 679                if (!dev->db_tab->page[i].db_rec)
 680                        continue;
 681
 682                if (!bitmap_empty(dev->db_tab->page[i].used, MTHCA_DB_REC_PER_PAGE))
 683                        mthca_warn(dev, "Kernel UARC page %d not empty\n", i);
 684
 685                mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 686
 687                dma_free_coherent(&dev->pdev->dev, MTHCA_ICM_PAGE_SIZE,
 688                                  dev->db_tab->page[i].db_rec,
 689                                  dev->db_tab->page[i].mapping);
 690        }
 691
 692        kfree(dev->db_tab->page);
 693        kfree(dev->db_tab);
 694}
 695