usr/src/uts/common/fs/zfs/ddt.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #include <sys/zfs_context.h>
  28 #include <sys/spa.h>
  29 #include <sys/spa_impl.h>
  30 #include <sys/zio.h>
  31 #include <sys/ddt.h>
  32 #include <sys/zap.h>
  33 #include <sys/dmu_tx.h>
  34 #include <sys/arc.h>
  35 #include <sys/zio_checksum.h>
  36 #include <sys/zio_compress.h>
  37
  38 static const ddt_ops_t *ddt_ops[DDT_TYPES] = {
  39         &ddt_zap_ops,
  40 };
  41
  42 static const char *ddt_class_name[DDT_CLASSES] = {
  43         "ditto",
  44         "duplicate",
  45         "unique",
  46 };
  47
  48 static void
  49 ddt_object_create(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
  50     dmu_tx_t *tx)
  51 {
  52         spa_t *spa = ddt->ddt_spa;
  53         objset_t *os = ddt->ddt_os;
  54         uint64_t *objectp = &ddt->ddt_object[type][class];
  55         boolean_t prehash = zio_checksum_table[ddt->ddt_checksum].ci_dedup;
  56         char name[DDT_NAMELEN];
  57
  58         ddt_object_name(ddt, type, class, name);
  59
  60         ASSERT(*objectp == 0);
  61         VERIFY(ddt_ops[type]->ddt_op_create(os, objectp, tx, prehash) == 0);
  62         ASSERT(*objectp != 0);
  63
  64         VERIFY(zap_add(os, DMU_POOL_DIRECTORY_OBJECT, name,
  65             sizeof (uint64_t), 1, objectp, tx) == 0);
  66
  67         VERIFY(zap_add(os, spa->spa_ddt_stat_object, name,
  68             sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
  69             &ddt->ddt_histogram[type][class], tx) == 0);
  70 }
  71
  72 static void
  73 ddt_object_destroy(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
  74     dmu_tx_t *tx)
  75 {
  76         spa_t *spa = ddt->ddt_spa;
  77         objset_t *os = ddt->ddt_os;
  78         uint64_t *objectp = &ddt->ddt_object[type][class];
  79         char name[DDT_NAMELEN];
  80
  81         ddt_object_name(ddt, type, class, name);
  82
  83         ASSERT(*objectp != 0);
  84         ASSERT(ddt_object_count(ddt, type, class) == 0);
  85         ASSERT(ddt_histogram_empty(&ddt->ddt_histogram[type][class]));
  86         VERIFY(zap_remove(os, DMU_POOL_DIRECTORY_OBJECT, name, tx) == 0);
  87         VERIFY(zap_remove(os, spa->spa_ddt_stat_object, name, tx) == 0);
  88         VERIFY(ddt_ops[type]->ddt_op_destroy(os, *objectp, tx) == 0);
  89
  90         *objectp = 0;
  91 }
  92
  93 static int
  94 ddt_object_load(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
  95 {
  96         char name[DDT_NAMELEN];
  97         int error;
  98
  99         ddt_object_name(ddt, type, class, name);
 100
 101         error = zap_lookup(ddt->ddt_os, DMU_POOL_DIRECTORY_OBJECT, name,
 102             sizeof (uint64_t), 1, &ddt->ddt_object[type][class]);
 103
 104         if (error)
 105                 return (error);
 106
 107         error = zap_lookup(ddt->ddt_os, ddt->ddt_spa->spa_ddt_stat_object, name,
 108             sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
 109             &ddt->ddt_histogram[type][class]);
 110
 111         ASSERT(error == 0);
 112         return (error);
 113 }
 114
 115 static void
 116 ddt_object_sync(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 117     dmu_tx_t *tx)
 118 {
 119         char name[DDT_NAMELEN];
 120
 121         ddt_object_name(ddt, type, class, name);
 122
 123         VERIFY(zap_update(ddt->ddt_os, ddt->ddt_spa->spa_ddt_stat_object, name,
 124             sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
 125             &ddt->ddt_histogram[type][class], tx) == 0);
 126 }
 127
 128 static int
 129 ddt_object_lookup(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 130     ddt_entry_t *dde)
 131 {
 132         if (!ddt_object_exists(ddt, type, class))
 133                 return (ENOENT);
 134
 135         return (ddt_ops[type]->ddt_op_lookup(ddt->ddt_os,
 136             ddt->ddt_object[type][class], dde));
 137 }
 138
 139 static int
 140 ddt_object_update(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 141     ddt_entry_t *dde, dmu_tx_t *tx)
 142 {
 143         ASSERT(ddt_object_exists(ddt, type, class));
 144
 145         return (ddt_ops[type]->ddt_op_update(ddt->ddt_os,
 146             ddt->ddt_object[type][class], dde, tx));
 147 }
 148
 149 static int
 150 ddt_object_remove(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 151     ddt_entry_t *dde, dmu_tx_t *tx)
 152 {
 153         ASSERT(ddt_object_exists(ddt, type, class));
 154
 155         return (ddt_ops[type]->ddt_op_remove(ddt->ddt_os,
 156             ddt->ddt_object[type][class], dde, tx));
 157 }
 158
 159 int
 160 ddt_object_walk(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 161     ddt_entry_t *dde, uint64_t *walk)
 162 {
 163         ASSERT(ddt_object_exists(ddt, type, class));
 164
 165         return (ddt_ops[type]->ddt_op_walk(ddt->ddt_os,
 166             ddt->ddt_object[type][class], dde, walk));
 167 }
 168
 169 uint64_t
 170 ddt_object_count(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
 171 {
 172         ASSERT(ddt_object_exists(ddt, type, class));
 173
 174         return (ddt_ops[type]->ddt_op_count(ddt->ddt_os,
 175             ddt->ddt_object[type][class]));
 176 }
 177
 178 int
 179 ddt_object_info(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 180     dmu_object_info_t *doi)
 181 {
 182         if (!ddt_object_exists(ddt, type, class))
 183                 return (ENOENT);
 184
 185         return (dmu_object_info(ddt->ddt_os, ddt->ddt_object[type][class],
 186             doi));
 187 }
 188
 189 boolean_t
 190 ddt_object_exists(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
 191 {
 192         return (!!ddt->ddt_object[type][class]);
 193 }
 194
 195 void
 196 ddt_object_name(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
 197     char *name)
 198 {
 199         (void) sprintf(name, DMU_POOL_DDT,
 200             zio_checksum_table[ddt->ddt_checksum].ci_name,
 201             ddt_ops[type]->ddt_op_name, ddt_class_name[class]);
 202 }
 203
 204 void
 205 ddt_bp_fill(const ddt_phys_t *ddp, blkptr_t *bp, uint64_t txg)
 206 {
 207         ASSERT(txg != 0);
 208
 209         for (int d = 0; d < SPA_DVAS_PER_BP; d++)
 210                 bp->blk_dva[d] = ddp->ddp_dva[d];
 211         BP_SET_BIRTH(bp, txg, ddp->ddp_phys_birth);
 212 }
 213
 214 void
 215 ddt_bp_create(const ddt_t *ddt, const ddt_key_t *ddk, const ddt_phys_t *ddp,
 216     blkptr_t *bp)
 217 {
 218         BP_ZERO(bp);
 219
 220         if (ddp != NULL)
 221                 ddt_bp_fill(ddp, bp, ddp->ddp_phys_birth);
 222
 223         bp->blk_cksum = ddk->ddk_cksum;
 224
 225         BP_SET_LSIZE(bp, DDK_GET_LSIZE(ddk));
 226         BP_SET_PSIZE(bp, DDK_GET_PSIZE(ddk));
 227         BP_SET_COMPRESS(bp, DDK_GET_COMPRESS(ddk));
 228         BP_SET_CHECKSUM(bp, ddt->ddt_checksum);
 229         BP_SET_TYPE(bp, DMU_OT_NONE);
 230         BP_SET_LEVEL(bp, 0);
 231         BP_SET_DEDUP(bp, 0);
 232         BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
 233 }
 234
 235 void
 236 ddt_key_fill(ddt_key_t *ddk, const blkptr_t *bp)
 237 {
 238         ddk->ddk_cksum = bp->blk_cksum;
 239         ddk->ddk_prop = 0;
 240
 241         DDK_SET_LSIZE(ddk, BP_GET_LSIZE(bp));
 242         DDK_SET_PSIZE(ddk, BP_GET_PSIZE(bp));
 243         DDK_SET_COMPRESS(ddk, BP_GET_COMPRESS(bp));
 244 }
 245
 246 void
 247 ddt_phys_fill(ddt_phys_t *ddp, const blkptr_t *bp)
 248 {
 249         ASSERT(ddp->ddp_phys_birth == 0);
 250
 251         for (int d = 0; d < SPA_DVAS_PER_BP; d++)
 252                 ddp->ddp_dva[d] = bp->blk_dva[d];
 253         ddp->ddp_phys_birth = BP_PHYSICAL_BIRTH(bp);
 254 }
 255
 256 void
 257 ddt_phys_clear(ddt_phys_t *ddp)
 258 {
 259         bzero(ddp, sizeof (*ddp));
 260 }
 261
 262 void
 263 ddt_phys_addref(ddt_phys_t *ddp)
 264 {
 265         ddp->ddp_refcnt++;
 266 }
 267
 268 void
 269 ddt_phys_decref(ddt_phys_t *ddp)
 270 {
 271         ASSERT((int64_t)ddp->ddp_refcnt > 0);
 272         ddp->ddp_refcnt--;
 273 }
 274
 275 void
 276 ddt_phys_free(ddt_t *ddt, ddt_key_t *ddk, ddt_phys_t *ddp, uint64_t txg)
 277 {
 278         blkptr_t blk;
 279
 280         ddt_bp_create(ddt, ddk, ddp, &blk);
 281         ddt_phys_clear(ddp);
 282         zio_free(ddt->ddt_spa, txg, &blk);
 283 }
 284
 285 ddt_phys_t *
 286 ddt_phys_select(const ddt_entry_t *dde, const blkptr_t *bp)
 287 {
 288         ddt_phys_t *ddp = (ddt_phys_t *)dde->dde_phys;
 289
 290         for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
 291                 if (DVA_EQUAL(BP_IDENTITY(bp), &ddp->ddp_dva[0]) &&
 292                     BP_PHYSICAL_BIRTH(bp) == ddp->ddp_phys_birth)
 293                         return (ddp);
 294         }
 295         return (NULL);
 296 }
 297
 298 uint64_t
 299 ddt_phys_total_refcnt(const ddt_entry_t *dde)
 300 {
 301         uint64_t refcnt = 0;
 302
 303         for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++)
 304                 refcnt += dde->dde_phys[p].ddp_refcnt;
 305
 306         return (refcnt);
 307 }
 308
 309 static void
 310 ddt_stat_generate(ddt_t *ddt, ddt_entry_t *dde, ddt_stat_t *dds)
 311 {
 312         spa_t *spa = ddt->ddt_spa;
 313         ddt_phys_t *ddp = dde->dde_phys;
 314         ddt_key_t *ddk = &dde->dde_key;
 315         uint64_t lsize = DDK_GET_LSIZE(ddk);
 316         uint64_t psize = DDK_GET_PSIZE(ddk);
 317
 318         bzero(dds, sizeof (*dds));
 319
 320         for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
 321                 uint64_t dsize = 0;
 322                 uint64_t refcnt = ddp->ddp_refcnt;
 323
 324                 if (ddp->ddp_phys_birth == 0)
 325                         continue;
 326
 327                 for (int d = 0; d < SPA_DVAS_PER_BP; d++)
 328                         dsize += dva_get_dsize_sync(spa, &ddp->ddp_dva[d]);
 329
 330                 dds->dds_blocks += 1;
 331                 dds->dds_lsize += lsize;
 332                 dds->dds_psize += psize;
 333                 dds->dds_dsize += dsize;
 334
 335                 dds->dds_ref_blocks += refcnt;
 336                 dds->dds_ref_lsize += lsize * refcnt;
 337                 dds->dds_ref_psize += psize * refcnt;
 338                 dds->dds_ref_dsize += dsize * refcnt;
 339         }
 340 }
 341
 342 void
 343 ddt_stat_add(ddt_stat_t *dst, const ddt_stat_t *src, uint64_t neg)
 344 {
 345         const uint64_t *s = (const uint64_t *)src;
 346         uint64_t *d = (uint64_t *)dst;
 347         uint64_t *d_end = (uint64_t *)(dst + 1);
 348
 349         ASSERT(neg == 0 || neg == -1ULL);       /* add or subtract */
 350
 351         while (d < d_end)
 352                 *d++ += (*s++ ^ neg) - neg;
 353 }
 354
 355 static void
 356 ddt_stat_update(ddt_t *ddt, ddt_entry_t *dde, uint64_t neg)
 357 {
 358         ddt_stat_t dds;
 359         ddt_histogram_t *ddh;
 360         int bucket;
 361
 362         ddt_stat_generate(ddt, dde, &dds);
 363
 364         bucket = highbit(dds.dds_ref_blocks) - 1;
 365         ASSERT(bucket >= 0);
 366
 367         ddh = &ddt->ddt_histogram[dde->dde_type][dde->dde_class];
 368
 369         ddt_stat_add(&ddh->ddh_stat[bucket], &dds, neg);
 370 }
 371
 372 void
 373 ddt_histogram_add(ddt_histogram_t *dst, const ddt_histogram_t *src)
 374 {
 375         for (int h = 0; h < 64; h++)
 376                 ddt_stat_add(&dst->ddh_stat[h], &src->ddh_stat[h], 0);
 377 }
 378
 379 void
 380 ddt_histogram_stat(ddt_stat_t *dds, const ddt_histogram_t *ddh)
 381 {
 382         bzero(dds, sizeof (*dds));
 383
 384         for (int h = 0; h < 64; h++)
 385                 ddt_stat_add(dds, &ddh->ddh_stat[h], 0);
 386 }
 387
 388 boolean_t
 389 ddt_histogram_empty(const ddt_histogram_t *ddh)
 390 {
 391         const uint64_t *s = (const uint64_t *)ddh;
 392         const uint64_t *s_end = (const uint64_t *)(ddh + 1);
 393
 394         while (s < s_end)
 395                 if (*s++ != 0)
 396                         return (B_FALSE);
 397
 398         return (B_TRUE);
 399 }
 400
 401 static void
 402 ddt_get_dedup_stats(spa_t *spa, ddt_stat_t *dds_total)
 403 {
 404         ddt_histogram_t ddh_total = { 0 };
 405
 406         for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
 407                 ddt_t *ddt = spa->spa_ddt[c];
 408                 for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
 409                         for (enum ddt_class class = 0; class < DDT_CLASSES;
 410                             class++) {
 411                                 ddt_histogram_add(&ddh_total,
 412                                     &ddt->ddt_histogram[type][class]);
 413                         }
 414                 }
 415         }
 416
 417         ddt_histogram_stat(dds_total, &ddh_total);
 418 }
 419
 420 uint64_t
 421 ddt_get_dedup_dspace(spa_t *spa)
 422 {
 423         ddt_stat_t dds_total = { 0 };
 424
 425         ddt_get_dedup_stats(spa, &dds_total);
 426         return (dds_total.dds_ref_dsize - dds_total.dds_dsize);
 427 }
 428
 429 uint64_t
 430 ddt_get_pool_dedup_ratio(spa_t *spa)
 431 {
 432         ddt_stat_t dds_total = { 0 };
 433
 434         ddt_get_dedup_stats(spa, &dds_total);
 435         if (dds_total.dds_dsize == 0)
 436                 return (100);
 437
 438         return (dds_total.dds_ref_dsize * 100 / dds_total.dds_dsize);
 439 }
 440
 441 int
 442 ddt_ditto_copies_needed(ddt_t *ddt, ddt_entry_t *dde, ddt_phys_t *ddp_willref)
 443 {
 444         spa_t *spa = ddt->ddt_spa;
 445         uint64_t total_refcnt = 0;
 446         uint64_t ditto = spa->spa_dedup_ditto;
 447         int total_copies = 0;
 448         int desired_copies = 0;
 449
 450         for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
 451                 ddt_phys_t *ddp = &dde->dde_phys[p];
 452                 zio_t *zio = dde->dde_lead_zio[p];
 453                 uint64_t refcnt = ddp->ddp_refcnt;      /* committed refs */
 454                 if (zio != NULL)
 455                         refcnt += zio->io_parent_count; /* pending refs */
 456                 if (ddp == ddp_willref)
 457                         refcnt++;                       /* caller's ref */
 458                 if (refcnt != 0) {
 459                         total_refcnt += refcnt;
 460                         total_copies += p;
 461                 }
 462         }
 463
 464         if (ditto == 0 || ditto > UINT32_MAX)
 465                 ditto = UINT32_MAX;
 466
 467         if (total_refcnt >= 1)
 468                 desired_copies++;
 469         if (total_refcnt >= ditto)
 470                 desired_copies++;
 471         if (total_refcnt >= ditto * ditto)
 472                 desired_copies++;
 473
 474         return (MAX(desired_copies, total_copies) - total_copies);
 475 }
 476
 477 int
 478 ddt_ditto_copies_present(ddt_entry_t *dde)
 479 {
 480         ddt_phys_t *ddp = &dde->dde_phys[DDT_PHYS_DITTO];
 481         dva_t *dva = ddp->ddp_dva;
 482         int copies = 0 - DVA_GET_GANG(dva);
 483
 484         for (int d = 0; d < SPA_DVAS_PER_BP; d++, dva++)
 485                 if (DVA_IS_VALID(dva))
 486                         copies++;
 487
 488         ASSERT(copies >= 0 && copies < SPA_DVAS_PER_BP);
 489
 490         return (copies);
 491 }
 492
 493 size_t
 494 ddt_compress(void *src, uchar_t *dst, size_t s_len, size_t d_len)
 495 {
 496         uchar_t *version = dst++;
 497         int cpfunc = ZIO_COMPRESS_ZLE;
 498         zio_compress_info_t *ci = &zio_compress_table[cpfunc];
 499         size_t c_len;
 500
 501         ASSERT(d_len >= s_len + 1);     /* no compression plus version byte */
 502
 503         c_len = ci->ci_compress(src, dst, s_len, d_len - 1, ci->ci_level);
 504
 505         if (c_len == s_len) {
 506                 cpfunc = ZIO_COMPRESS_OFF;
 507                 bcopy(src, dst, s_len);
 508         }
 509
 510         *version = (ZFS_HOST_BYTEORDER & DDT_COMPRESS_BYTEORDER_MASK) | cpfunc;
 511
 512         return (c_len + 1);
 513 }
 514
 515 void
 516 ddt_decompress(uchar_t *src, void *dst, size_t s_len, size_t d_len)
 517 {
 518         uchar_t version = *src++;
 519         int cpfunc = version & DDT_COMPRESS_FUNCTION_MASK;
 520         zio_compress_info_t *ci = &zio_compress_table[cpfunc];
 521
 522         if (ci->ci_decompress != NULL)
 523                 (void) ci->ci_decompress(src, dst, s_len, d_len, ci->ci_level);
 524         else
 525                 bcopy(src, dst, d_len);
 526
 527         if ((version ^ ZFS_HOST_BYTEORDER) & DDT_COMPRESS_BYTEORDER_MASK)
 528                 byteswap_uint64_array(dst, d_len);
 529 }
 530
 531 ddt_t *
 532 ddt_select_by_checksum(spa_t *spa, enum zio_checksum c)
 533 {
 534         return (spa->spa_ddt[c]);
 535 }
 536
 537 ddt_t *
 538 ddt_select(spa_t *spa, const blkptr_t *bp)
 539 {
 540         return (spa->spa_ddt[BP_GET_CHECKSUM(bp)]);
 541 }
 542
 543 void
 544 ddt_enter(ddt_t *ddt)
 545 {
 546         mutex_enter(&ddt->ddt_lock);
 547 }
 548
 549 void
 550 ddt_exit(ddt_t *ddt)
 551 {
 552         mutex_exit(&ddt->ddt_lock);
 553 }
 554
 555 static ddt_entry_t *
 556 ddt_alloc(const ddt_key_t *ddk)
 557 {
 558         ddt_entry_t *dde;
 559
 560         dde = kmem_zalloc(sizeof (ddt_entry_t), KM_SLEEP);
 561         cv_init(&dde->dde_cv, NULL, CV_DEFAULT, NULL);
 562
 563         dde->dde_key = *ddk;
 564
 565         return (dde);
 566 }
 567
 568 static void
 569 ddt_free(ddt_entry_t *dde)
 570 {
 571         ASSERT(!dde->dde_loading);
 572
 573         for (int p = 0; p < DDT_PHYS_TYPES; p++)
 574                 ASSERT(dde->dde_lead_zio[p] == NULL);
 575
 576         if (dde->dde_repair_data != NULL)
 577                 zio_buf_free(dde->dde_repair_data,
 578                     DDK_GET_PSIZE(&dde->dde_key));
 579
 580         cv_destroy(&dde->dde_cv);
 581         kmem_free(dde, sizeof (*dde));
 582 }
 583
 584 void
 585 ddt_remove(ddt_t *ddt, ddt_entry_t *dde)
 586 {
 587         ASSERT(MUTEX_HELD(&ddt->ddt_lock));
 588
 589         avl_remove(&ddt->ddt_tree, dde);
 590         ddt_free(dde);
 591 }
 592
 593 ddt_entry_t *
 594 ddt_lookup(ddt_t *ddt, const blkptr_t *bp, boolean_t add)
 595 {
 596         ddt_entry_t *dde, dde_search;
 597         enum ddt_type type;
 598         enum ddt_class class;
 599         avl_index_t where;
 600         int error;
 601
 602         ASSERT(MUTEX_HELD(&ddt->ddt_lock));
 603
 604         ddt_key_fill(&dde_search.dde_key, bp);
 605
 606         dde = avl_find(&ddt->ddt_tree, &dde_search, &where);
 607         if (dde == NULL) {
 608                 if (!add)
 609                         return (NULL);
 610                 dde = ddt_alloc(&dde_search.dde_key);
 611                 avl_insert(&ddt->ddt_tree, dde, where);
 612         }
 613
 614         while (dde->dde_loading)
 615                 cv_wait(&dde->dde_cv, &ddt->ddt_lock);
 616
 617         if (dde->dde_loaded)
 618                 return (dde);
 619
 620         dde->dde_loading = B_TRUE;
 621
 622         ddt_exit(ddt);
 623
 624         error = ENOENT;
 625
 626         for (type = 0; type < DDT_TYPES; type++) {
 627                 for (class = 0; class < DDT_CLASSES; class++) {
 628                         error = ddt_object_lookup(ddt, type, class, dde);
 629                         if (error != ENOENT)
 630                                 break;
 631                 }
 632                 if (error != ENOENT)
 633                         break;
 634         }
 635
 636         ASSERT(error == 0 || error == ENOENT);
 637
 638         ddt_enter(ddt);
 639
 640         ASSERT(dde->dde_loaded == B_FALSE);
 641         ASSERT(dde->dde_loading == B_TRUE);
 642
 643         dde->dde_type = type;   /* will be DDT_TYPES if no entry found */
 644         dde->dde_class = class; /* will be DDT_CLASSES if no entry found */
 645         dde->dde_loaded = B_TRUE;
 646         dde->dde_loading = B_FALSE;
 647
 648         if (error == 0)
 649                 ddt_stat_update(ddt, dde, -1ULL);
 650
 651         cv_broadcast(&dde->dde_cv);
 652
 653         return (dde);
 654 }
 655
 656 int
 657 ddt_entry_compare(const void *x1, const void *x2)
 658 {
 659         const ddt_entry_t *dde1 = x1;
 660         const ddt_entry_t *dde2 = x2;
 661         const uint64_t *u1 = (const uint64_t *)&dde1->dde_key;
 662         const uint64_t *u2 = (const uint64_t *)&dde2->dde_key;
 663
 664         for (int i = 0; i < DDT_KEY_WORDS; i++) {
 665                 if (u1[i] < u2[i])
 666                         return (-1);
 667                 if (u1[i] > u2[i])
 668                         return (1);
 669         }
 670
 671         return (0);
 672 }
 673
 674 static ddt_t *
 675 ddt_table_alloc(spa_t *spa, enum zio_checksum c)
 676 {
 677         ddt_t *ddt;
 678
 679         ddt = kmem_zalloc(sizeof (*ddt), KM_SLEEP);
 680
 681         mutex_init(&ddt->ddt_lock, NULL, MUTEX_DEFAULT, NULL);
 682         avl_create(&ddt->ddt_tree, ddt_entry_compare,
 683             sizeof (ddt_entry_t), offsetof(ddt_entry_t, dde_node));
 684         avl_create(&ddt->ddt_repair_tree, ddt_entry_compare,
 685             sizeof (ddt_entry_t), offsetof(ddt_entry_t, dde_node));
 686         ddt->ddt_checksum = c;
 687         ddt->ddt_spa = spa;
 688         ddt->ddt_os = spa->spa_meta_objset;
 689
 690         return (ddt);
 691 }
 692
 693 static void
 694 ddt_table_free(ddt_t *ddt)
 695 {
 696         ASSERT(avl_numnodes(&ddt->ddt_tree) == 0);
 697         ASSERT(avl_numnodes(&ddt->ddt_repair_tree) == 0);
 698         avl_destroy(&ddt->ddt_tree);
 699         avl_destroy(&ddt->ddt_repair_tree);
 700         mutex_destroy(&ddt->ddt_lock);
 701         kmem_free(ddt, sizeof (*ddt));
 702 }
 703
 704 void
 705 ddt_create(spa_t *spa)
 706 {
 707         spa->spa_dedup_checksum = ZIO_DEDUPCHECKSUM;
 708
 709         for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++)
 710                 spa->spa_ddt[c] = ddt_table_alloc(spa, c);
 711 }
 712
 713 int
 714 ddt_load(spa_t *spa)
 715 {
 716         int error;
 717
 718         ddt_create(spa);
 719
 720         error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
 721             DMU_POOL_DDT_STATS, sizeof (uint64_t), 1,
 722             &spa->spa_ddt_stat_object);
 723
 724         if (error)
 725                 return (error == ENOENT ? 0 : error);
 726
 727         for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
 728                 for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
 729                         for (enum ddt_class class = 0; class < DDT_CLASSES;
 730                             class++) {
 731                                 ddt_t *ddt = spa->spa_ddt[c];
 732                                 error = ddt_object_load(ddt, type, class);
 733                                 if (error != 0 && error != ENOENT)
 734                                         return (error);
 735                         }
 736                 }
 737         }
 738
 739         return (0);
 740 }
 741
 742 void
 743 ddt_unload(spa_t *spa)
 744 {
 745         for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
 746                 if (spa->spa_ddt[c]) {
 747                         ddt_table_free(spa->spa_ddt[c]);
 748                         spa->spa_ddt[c] = NULL;
 749                 }
 750         }
 751 }
 752
 753 ddt_entry_t *
 754 ddt_repair_start(ddt_t *ddt, const blkptr_t *bp)
 755 {
 756         ddt_key_t ddk;
 757         ddt_entry_t *dde;
 758
 759         ddt_key_fill(&ddk, bp);
 760
 761         dde = ddt_alloc(&ddk);
 762
 763         for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
 764                 for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
 765                         /*
 766                          * We can only do repair if there are multiple copies
 767                          * of the block.  For anything in the UNIQUE class,
 768                          * there's definitely only one copy, so don't even try.
 769                          */
 770                         if (class != DDT_CLASS_UNIQUE &&
 771                             ddt_object_lookup(ddt, type, class, dde) == 0)
 772                                 return (dde);
 773                 }
 774         }
 775
 776         bzero(dde->dde_phys, sizeof (dde->dde_phys));
 777
 778         return (dde);
 779 }
 780
 781 void
 782 ddt_repair_done(ddt_t *ddt, ddt_entry_t *dde)
 783 {
 784         avl_index_t where;
 785
 786         ddt_enter(ddt);
 787
 788         if (dde->dde_repair_data != NULL && spa_writeable(ddt->ddt_spa) &&
 789             avl_find(&ddt->ddt_repair_tree, dde, &where) == NULL)
 790                 avl_insert(&ddt->ddt_repair_tree, dde, where);
 791         else
 792                 ddt_free(dde);
 793
 794         ddt_exit(ddt);
 795 }
 796
 797 static void
 798 ddt_repair_entry_done(zio_t *zio)
 799 {
 800         ddt_entry_t *rdde = zio->io_private;
 801
 802         ddt_free(rdde);
 803 }
 804
 805 static void
 806 ddt_repair_entry(ddt_t *ddt, ddt_entry_t *dde, ddt_entry_t *rdde, zio_t *rio)
 807 {
 808         ddt_phys_t *ddp = dde->dde_phys;
 809         ddt_phys_t *rddp = rdde->dde_phys;
 810         ddt_key_t *ddk = &dde->dde_key;
 811         ddt_key_t *rddk = &rdde->dde_key;
 812         zio_t *zio;
 813         blkptr_t blk;
 814
 815         zio = zio_null(rio, rio->io_spa, NULL,
 816             ddt_repair_entry_done, rdde, rio->io_flags);
 817
 818         for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++, rddp++) {
 819                 if (ddp->ddp_phys_birth == 0 ||
 820                     ddp->ddp_phys_birth != rddp->ddp_phys_birth ||
 821                     bcmp(ddp->ddp_dva, rddp->ddp_dva, sizeof (ddp->ddp_dva)))
 822                         continue;
 823                 ddt_bp_create(ddt, ddk, ddp, &blk);
 824                 zio_nowait(zio_rewrite(zio, zio->io_spa, 0, &blk,
 825                     rdde->dde_repair_data, DDK_GET_PSIZE(rddk), NULL, NULL,
 826                     ZIO_PRIORITY_SYNC_WRITE, ZIO_DDT_CHILD_FLAGS(zio), NULL));
 827         }
 828
 829         zio_nowait(zio);
 830 }
 831
 832 static void
 833 ddt_repair_table(ddt_t *ddt, zio_t *rio)
 834 {
 835         spa_t *spa = ddt->ddt_spa;
 836         ddt_entry_t *dde, *rdde_next, *rdde;
 837         avl_tree_t *t = &ddt->ddt_repair_tree;
 838         blkptr_t blk;
 839
 840         if (spa_sync_pass(spa) > 1)
 841                 return;
 842
 843         ddt_enter(ddt);
 844         for (rdde = avl_first(t); rdde != NULL; rdde = rdde_next) {
 845                 rdde_next = AVL_NEXT(t, rdde);
 846                 avl_remove(&ddt->ddt_repair_tree, rdde);
 847                 ddt_exit(ddt);
 848                 ddt_bp_create(ddt, &rdde->dde_key, NULL, &blk);
 849                 dde = ddt_repair_start(ddt, &blk);
 850                 ddt_repair_entry(ddt, dde, rdde, rio);
 851                 ddt_repair_done(ddt, dde);
 852                 ddt_enter(ddt);
 853         }
 854         ddt_exit(ddt);
 855 }
 856
 857 static void
 858 ddt_sync_entry(ddt_t *ddt, ddt_entry_t *dde, dmu_tx_t *tx, uint64_t txg)
 859 {
 860         ddt_phys_t *ddp = dde->dde_phys;
 861         ddt_key_t *ddk = &dde->dde_key;
 862         enum ddt_type otype = dde->dde_type;
 863         enum ddt_type ntype = DDT_TYPE_CURRENT;
 864         enum ddt_class oclass = dde->dde_class;
 865         enum ddt_class nclass;
 866         uint64_t total_refcnt = 0;
 867
 868         ASSERT(dde->dde_loaded);
 869         ASSERT(!dde->dde_loading);
 870
 871         for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
 872                 ASSERT(dde->dde_lead_zio[p] == NULL);
 873                 ASSERT((int64_t)ddp->ddp_refcnt >= 0);
 874                 if (ddp->ddp_phys_birth == 0) {
 875                         ASSERT(ddp->ddp_refcnt == 0);
 876                         continue;
 877                 }
 878                 if (p == DDT_PHYS_DITTO) {
 879                         if (ddt_ditto_copies_needed(ddt, dde, NULL) == 0)
 880                                 ddt_phys_free(ddt, ddk, ddp, txg);
 881                         continue;
 882                 }
 883                 if (ddp->ddp_refcnt == 0)
 884                         ddt_phys_free(ddt, ddk, ddp, txg);
 885                 total_refcnt += ddp->ddp_refcnt;
 886         }
 887
 888         if (dde->dde_phys[DDT_PHYS_DITTO].ddp_phys_birth != 0)
 889                 nclass = DDT_CLASS_DITTO;
 890         else if (total_refcnt > 1)
 891                 nclass = DDT_CLASS_DUPLICATE;
 892         else
 893                 nclass = DDT_CLASS_UNIQUE;
 894
 895         if (otype != DDT_TYPES &&
 896             (otype != ntype || oclass != nclass || total_refcnt == 0)) {
 897                 VERIFY(ddt_object_remove(ddt, otype, oclass, dde, tx) == 0);
 898                 ASSERT(ddt_object_lookup(ddt, otype, oclass, dde) == ENOENT);
 899         }
 900
 901         if (total_refcnt != 0) {
 902                 dde->dde_type = ntype;
 903                 dde->dde_class = nclass;
 904                 ddt_stat_update(ddt, dde, 0);
 905                 if (!ddt_object_exists(ddt, ntype, nclass))
 906                         ddt_object_create(ddt, ntype, nclass, tx);
 907                 VERIFY(ddt_object_update(ddt, ntype, nclass, dde, tx) == 0);
 908         }
 909 }
 910
 911 static void
 912 ddt_sync_table(ddt_t *ddt, dmu_tx_t *tx, uint64_t txg)
 913 {
 914         spa_t *spa = ddt->ddt_spa;
 915         ddt_entry_t *dde;
 916         void *cookie = NULL;
 917
 918         if (avl_numnodes(&ddt->ddt_tree) == 0)
 919                 return;
 920
 921         ASSERT(spa_sync_pass(spa) == 1);
 922         ASSERT(spa->spa_uberblock.ub_version >= SPA_VERSION_DEDUP);
 923
 924         if (spa->spa_ddt_stat_object == 0) {
 925                 spa->spa_ddt_stat_object = zap_create(ddt->ddt_os,
 926                     DMU_OT_DDT_STATS, DMU_OT_NONE, 0, tx);
 927                 VERIFY(zap_add(ddt->ddt_os, DMU_POOL_DIRECTORY_OBJECT,
 928                     DMU_POOL_DDT_STATS, sizeof (uint64_t), 1,
 929                     &spa->spa_ddt_stat_object, tx) == 0);
 930         }
 931
 932         while ((dde = avl_destroy_nodes(&ddt->ddt_tree, &cookie)) != NULL) {
 933                 ddt_sync_entry(ddt, dde, tx, txg);
 934                 ddt_free(dde);
 935         }
 936
 937         for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
 938                 for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
 939                         if (!ddt_object_exists(ddt, type, class))
 940                                 continue;
 941                         ddt_object_sync(ddt, type, class, tx);
 942                         if (ddt_object_count(ddt, type, class) == 0)
 943                                 ddt_object_destroy(ddt, type, class, tx);
 944                 }
 945         }
 946 }
 947
 948 void
 949 ddt_sync(spa_t *spa, uint64_t txg)
 950 {
 951         dmu_tx_t *tx;
 952         zio_t *rio = zio_root(spa, NULL, NULL,
 953             ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE);
 954
 955         ASSERT(spa_syncing_txg(spa) == txg);
 956
 957         tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
 958
 959         for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
 960                 ddt_t *ddt = spa->spa_ddt[c];
 961                 if (ddt == NULL)
 962                         continue;
 963                 ddt_sync_table(ddt, tx, txg);
 964                 ddt_repair_table(ddt, rio);
 965         }
 966
 967         (void) zio_wait(rio);
 968
 969         dmu_tx_commit(tx);
 970 }