granicus.if.org Git - zfs/blob - module/zfs/dsl_deadlist.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  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  23  * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
  24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
  25  */
  26
  27 #include <sys/dsl_dataset.h>
  28 #include <sys/dmu.h>
  29 #include <sys/refcount.h>
  30 #include <sys/zap.h>
  31 #include <sys/zfs_context.h>
  32 #include <sys/dsl_pool.h>
  33
  34 /*
  35  * Deadlist concurrency:
  36  *
  37  * Deadlists can only be modified from the syncing thread.
  38  *
  39  * Except for dsl_deadlist_insert(), it can only be modified with the
  40  * dp_config_rwlock held with RW_WRITER.
  41  *
  42  * The accessors (dsl_deadlist_space() and dsl_deadlist_space_range()) can
  43  * be called concurrently, from open context, with the dl_config_rwlock held
  44  * with RW_READER.
  45  *
  46  * Therefore, we only need to provide locking between dsl_deadlist_insert() and
  47  * the accessors, protecting:
  48  *     dl_phys->dl_used,comp,uncomp
  49  *     and protecting the dl_tree from being loaded.
  50  * The locking is provided by dl_lock.  Note that locking on the bpobj_t
  51  * provides its own locking, and dl_oldfmt is immutable.
  52  */
  53
  54 static int
  55 dsl_deadlist_compare(const void *arg1, const void *arg2)
  56 {
  57         const dsl_deadlist_entry_t *dle1 = (const dsl_deadlist_entry_t *)arg1;
  58         const dsl_deadlist_entry_t *dle2 = (const dsl_deadlist_entry_t *)arg2;
  59
  60         return (AVL_CMP(dle1->dle_mintxg, dle2->dle_mintxg));
  61 }
  62
  63 static void
  64 dsl_deadlist_load_tree(dsl_deadlist_t *dl)
  65 {
  66         zap_cursor_t zc;
  67         zap_attribute_t za;
  68
  69         ASSERT(MUTEX_HELD(&dl->dl_lock));
  70
  71         ASSERT(!dl->dl_oldfmt);
  72         if (dl->dl_havetree)
  73                 return;
  74
  75         avl_create(&dl->dl_tree, dsl_deadlist_compare,
  76             sizeof (dsl_deadlist_entry_t),
  77             offsetof(dsl_deadlist_entry_t, dle_node));
  78         for (zap_cursor_init(&zc, dl->dl_os, dl->dl_object);
  79             zap_cursor_retrieve(&zc, &za) == 0;
  80             zap_cursor_advance(&zc)) {
  81                 dsl_deadlist_entry_t *dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
  82                 dle->dle_mintxg = zfs_strtonum(za.za_name, NULL);
  83                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os,
  84                     za.za_first_integer));
  85                 avl_add(&dl->dl_tree, dle);
  86         }
  87         zap_cursor_fini(&zc);
  88         dl->dl_havetree = B_TRUE;
  89 }
  90
  91 void
  92 dsl_deadlist_open(dsl_deadlist_t *dl, objset_t *os, uint64_t object)
  93 {
  94         dmu_object_info_t doi;
  95
  96         ASSERT(!dsl_deadlist_is_open(dl));
  97
  98         mutex_init(&dl->dl_lock, NULL, MUTEX_DEFAULT, NULL);
  99         dl->dl_os = os;
 100         dl->dl_object = object;
 101         VERIFY3U(0, ==, dmu_bonus_hold(os, object, dl, &dl->dl_dbuf));
 102         dmu_object_info_from_db(dl->dl_dbuf, &doi);
 103         if (doi.doi_type == DMU_OT_BPOBJ) {
 104                 dmu_buf_rele(dl->dl_dbuf, dl);
 105                 dl->dl_dbuf = NULL;
 106                 dl->dl_oldfmt = B_TRUE;
 107                 VERIFY3U(0, ==, bpobj_open(&dl->dl_bpobj, os, object));
 108                 return;
 109         }
 110
 111         dl->dl_oldfmt = B_FALSE;
 112         dl->dl_phys = dl->dl_dbuf->db_data;
 113         dl->dl_havetree = B_FALSE;
 114 }
 115
 116 boolean_t
 117 dsl_deadlist_is_open(dsl_deadlist_t *dl)
 118 {
 119         return (dl->dl_os != NULL);
 120 }
 121
 122 void
 123 dsl_deadlist_close(dsl_deadlist_t *dl)
 124 {
 125         void *cookie = NULL;
 126         dsl_deadlist_entry_t *dle;
 127
 128         ASSERT(dsl_deadlist_is_open(dl));
 129         mutex_destroy(&dl->dl_lock);
 130
 131         if (dl->dl_oldfmt) {
 132                 dl->dl_oldfmt = B_FALSE;
 133                 bpobj_close(&dl->dl_bpobj);
 134                 dl->dl_os = NULL;
 135                 dl->dl_object = 0;
 136                 return;
 137         }
 138
 139         if (dl->dl_havetree) {
 140                 while ((dle = avl_destroy_nodes(&dl->dl_tree, &cookie))
 141                     != NULL) {
 142                         bpobj_close(&dle->dle_bpobj);
 143                         kmem_free(dle, sizeof (*dle));
 144                 }
 145                 avl_destroy(&dl->dl_tree);
 146         }
 147         dmu_buf_rele(dl->dl_dbuf, dl);
 148         dl->dl_dbuf = NULL;
 149         dl->dl_phys = NULL;
 150         dl->dl_os = NULL;
 151         dl->dl_object = 0;
 152 }
 153
 154 uint64_t
 155 dsl_deadlist_alloc(objset_t *os, dmu_tx_t *tx)
 156 {
 157         if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)
 158                 return (bpobj_alloc(os, SPA_OLD_MAXBLOCKSIZE, tx));
 159         return (zap_create(os, DMU_OT_DEADLIST, DMU_OT_DEADLIST_HDR,
 160             sizeof (dsl_deadlist_phys_t), tx));
 161 }
 162
 163 void
 164 dsl_deadlist_free(objset_t *os, uint64_t dlobj, dmu_tx_t *tx)
 165 {
 166         dmu_object_info_t doi;
 167         zap_cursor_t zc;
 168         zap_attribute_t za;
 169
 170         VERIFY3U(0, ==, dmu_object_info(os, dlobj, &doi));
 171         if (doi.doi_type == DMU_OT_BPOBJ) {
 172                 bpobj_free(os, dlobj, tx);
 173                 return;
 174         }
 175
 176         for (zap_cursor_init(&zc, os, dlobj);
 177             zap_cursor_retrieve(&zc, &za) == 0;
 178             zap_cursor_advance(&zc)) {
 179                 uint64_t obj = za.za_first_integer;
 180                 if (obj == dmu_objset_pool(os)->dp_empty_bpobj)
 181                         bpobj_decr_empty(os, tx);
 182                 else
 183                         bpobj_free(os, obj, tx);
 184         }
 185         zap_cursor_fini(&zc);
 186         VERIFY3U(0, ==, dmu_object_free(os, dlobj, tx));
 187 }
 188
 189 static void
 190 dle_enqueue(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
 191     const blkptr_t *bp, dmu_tx_t *tx)
 192 {
 193         ASSERT(MUTEX_HELD(&dl->dl_lock));
 194         if (dle->dle_bpobj.bpo_object ==
 195             dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
 196                 uint64_t obj = bpobj_alloc(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 197                 bpobj_close(&dle->dle_bpobj);
 198                 bpobj_decr_empty(dl->dl_os, tx);
 199                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 200                 VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
 201                     dle->dle_mintxg, obj, tx));
 202         }
 203         bpobj_enqueue(&dle->dle_bpobj, bp, tx);
 204 }
 205
 206 static void
 207 dle_enqueue_subobj(dsl_deadlist_t *dl, dsl_deadlist_entry_t *dle,
 208     uint64_t obj, dmu_tx_t *tx)
 209 {
 210         ASSERT(MUTEX_HELD(&dl->dl_lock));
 211         if (dle->dle_bpobj.bpo_object !=
 212             dmu_objset_pool(dl->dl_os)->dp_empty_bpobj) {
 213                 bpobj_enqueue_subobj(&dle->dle_bpobj, obj, tx);
 214         } else {
 215                 bpobj_close(&dle->dle_bpobj);
 216                 bpobj_decr_empty(dl->dl_os, tx);
 217                 VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 218                 VERIFY3U(0, ==, zap_update_int_key(dl->dl_os, dl->dl_object,
 219                     dle->dle_mintxg, obj, tx));
 220         }
 221 }
 222
 223 void
 224 dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp, dmu_tx_t *tx)
 225 {
 226         dsl_deadlist_entry_t dle_tofind;
 227         dsl_deadlist_entry_t *dle;
 228         avl_index_t where;
 229
 230         if (dl->dl_oldfmt) {
 231                 bpobj_enqueue(&dl->dl_bpobj, bp, tx);
 232                 return;
 233         }
 234
 235         mutex_enter(&dl->dl_lock);
 236         dsl_deadlist_load_tree(dl);
 237
 238         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 239         dl->dl_phys->dl_used +=
 240             bp_get_dsize_sync(dmu_objset_spa(dl->dl_os), bp);
 241         dl->dl_phys->dl_comp += BP_GET_PSIZE(bp);
 242         dl->dl_phys->dl_uncomp += BP_GET_UCSIZE(bp);
 243
 244         dle_tofind.dle_mintxg = bp->blk_birth;
 245         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 246         if (dle == NULL)
 247                 dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
 248         else
 249                 dle = AVL_PREV(&dl->dl_tree, dle);
 250
 251         if (dle == NULL) {
 252                 zfs_panic_recover("blkptr at %p has invalid BLK_BIRTH %llu",
 253                     bp, (longlong_t)bp->blk_birth);
 254                 dle = avl_first(&dl->dl_tree);
 255         }
 256
 257         ASSERT3P(dle, !=, NULL);
 258         dle_enqueue(dl, dle, bp, tx);
 259         mutex_exit(&dl->dl_lock);
 260 }
 261
 262 /*
 263  * Insert new key in deadlist, which must be > all current entries.
 264  * mintxg is not inclusive.
 265  */
 266 void
 267 dsl_deadlist_add_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 268 {
 269         uint64_t obj;
 270         dsl_deadlist_entry_t *dle;
 271
 272         if (dl->dl_oldfmt)
 273                 return;
 274
 275         dle = kmem_alloc(sizeof (*dle), KM_SLEEP);
 276         dle->dle_mintxg = mintxg;
 277
 278         mutex_enter(&dl->dl_lock);
 279         dsl_deadlist_load_tree(dl);
 280
 281         obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 282         VERIFY3U(0, ==, bpobj_open(&dle->dle_bpobj, dl->dl_os, obj));
 283         avl_add(&dl->dl_tree, dle);
 284
 285         VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, dl->dl_object,
 286             mintxg, obj, tx));
 287         mutex_exit(&dl->dl_lock);
 288 }
 289
 290 /*
 291  * Remove this key, merging its entries into the previous key.
 292  */
 293 void
 294 dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 295 {
 296         dsl_deadlist_entry_t dle_tofind;
 297         dsl_deadlist_entry_t *dle, *dle_prev;
 298
 299         if (dl->dl_oldfmt)
 300                 return;
 301
 302         mutex_enter(&dl->dl_lock);
 303         dsl_deadlist_load_tree(dl);
 304
 305         dle_tofind.dle_mintxg = mintxg;
 306         dle = avl_find(&dl->dl_tree, &dle_tofind, NULL);
 307         dle_prev = AVL_PREV(&dl->dl_tree, dle);
 308
 309         dle_enqueue_subobj(dl, dle_prev, dle->dle_bpobj.bpo_object, tx);
 310
 311         avl_remove(&dl->dl_tree, dle);
 312         bpobj_close(&dle->dle_bpobj);
 313         kmem_free(dle, sizeof (*dle));
 314
 315         VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object, mintxg, tx));
 316         mutex_exit(&dl->dl_lock);
 317 }
 318
 319 /*
 320  * Walk ds's snapshots to regenerate generate ZAP & AVL.
 321  */
 322 static void
 323 dsl_deadlist_regenerate(objset_t *os, uint64_t dlobj,
 324     uint64_t mrs_obj, dmu_tx_t *tx)
 325 {
 326         dsl_deadlist_t dl = { 0 };
 327         dsl_pool_t *dp = dmu_objset_pool(os);
 328
 329         dsl_deadlist_open(&dl, os, dlobj);
 330         if (dl.dl_oldfmt) {
 331                 dsl_deadlist_close(&dl);
 332                 return;
 333         }
 334
 335         while (mrs_obj != 0) {
 336                 dsl_dataset_t *ds;
 337                 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp, mrs_obj, FTAG, &ds));
 338                 dsl_deadlist_add_key(&dl,
 339                     dsl_dataset_phys(ds)->ds_prev_snap_txg, tx);
 340                 mrs_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
 341                 dsl_dataset_rele(ds, FTAG);
 342         }
 343         dsl_deadlist_close(&dl);
 344 }
 345
 346 uint64_t
 347 dsl_deadlist_clone(dsl_deadlist_t *dl, uint64_t maxtxg,
 348     uint64_t mrs_obj, dmu_tx_t *tx)
 349 {
 350         dsl_deadlist_entry_t *dle;
 351         uint64_t newobj;
 352
 353         newobj = dsl_deadlist_alloc(dl->dl_os, tx);
 354
 355         if (dl->dl_oldfmt) {
 356                 dsl_deadlist_regenerate(dl->dl_os, newobj, mrs_obj, tx);
 357                 return (newobj);
 358         }
 359
 360         mutex_enter(&dl->dl_lock);
 361         dsl_deadlist_load_tree(dl);
 362
 363         for (dle = avl_first(&dl->dl_tree); dle;
 364             dle = AVL_NEXT(&dl->dl_tree, dle)) {
 365                 uint64_t obj;
 366
 367                 if (dle->dle_mintxg >= maxtxg)
 368                         break;
 369
 370                 obj = bpobj_alloc_empty(dl->dl_os, SPA_OLD_MAXBLOCKSIZE, tx);
 371                 VERIFY3U(0, ==, zap_add_int_key(dl->dl_os, newobj,
 372                     dle->dle_mintxg, obj, tx));
 373         }
 374         mutex_exit(&dl->dl_lock);
 375         return (newobj);
 376 }
 377
 378 void
 379 dsl_deadlist_space(dsl_deadlist_t *dl,
 380     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
 381 {
 382         ASSERT(dsl_deadlist_is_open(dl));
 383         if (dl->dl_oldfmt) {
 384                 VERIFY3U(0, ==, bpobj_space(&dl->dl_bpobj,
 385                     usedp, compp, uncompp));
 386                 return;
 387         }
 388
 389         mutex_enter(&dl->dl_lock);
 390         *usedp = dl->dl_phys->dl_used;
 391         *compp = dl->dl_phys->dl_comp;
 392         *uncompp = dl->dl_phys->dl_uncomp;
 393         mutex_exit(&dl->dl_lock);
 394 }
 395
 396 /*
 397  * return space used in the range (mintxg, maxtxg].
 398  * Includes maxtxg, does not include mintxg.
 399  * mintxg and maxtxg must both be keys in the deadlist (unless maxtxg is
 400  * larger than any bp in the deadlist (eg. UINT64_MAX)).
 401  */
 402 void
 403 dsl_deadlist_space_range(dsl_deadlist_t *dl, uint64_t mintxg, uint64_t maxtxg,
 404     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
 405 {
 406         dsl_deadlist_entry_t *dle;
 407         dsl_deadlist_entry_t dle_tofind;
 408         avl_index_t where;
 409
 410         if (dl->dl_oldfmt) {
 411                 VERIFY3U(0, ==, bpobj_space_range(&dl->dl_bpobj,
 412                     mintxg, maxtxg, usedp, compp, uncompp));
 413                 return;
 414         }
 415
 416         *usedp = *compp = *uncompp = 0;
 417
 418         mutex_enter(&dl->dl_lock);
 419         dsl_deadlist_load_tree(dl);
 420         dle_tofind.dle_mintxg = mintxg;
 421         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 422         /*
 423          * If we don't find this mintxg, there shouldn't be anything
 424          * after it either.
 425          */
 426         ASSERT(dle != NULL ||
 427             avl_nearest(&dl->dl_tree, where, AVL_AFTER) == NULL);
 428
 429         for (; dle && dle->dle_mintxg < maxtxg;
 430             dle = AVL_NEXT(&dl->dl_tree, dle)) {
 431                 uint64_t used, comp, uncomp;
 432
 433                 VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
 434                     &used, &comp, &uncomp));
 435
 436                 *usedp += used;
 437                 *compp += comp;
 438                 *uncompp += uncomp;
 439         }
 440         mutex_exit(&dl->dl_lock);
 441 }
 442
 443 static void
 444 dsl_deadlist_insert_bpobj(dsl_deadlist_t *dl, uint64_t obj, uint64_t birth,
 445     dmu_tx_t *tx)
 446 {
 447         dsl_deadlist_entry_t dle_tofind;
 448         dsl_deadlist_entry_t *dle;
 449         avl_index_t where;
 450         uint64_t used, comp, uncomp;
 451         bpobj_t bpo;
 452
 453         ASSERT(MUTEX_HELD(&dl->dl_lock));
 454
 455         VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
 456         VERIFY3U(0, ==, bpobj_space(&bpo, &used, &comp, &uncomp));
 457         bpobj_close(&bpo);
 458
 459         dsl_deadlist_load_tree(dl);
 460
 461         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 462         dl->dl_phys->dl_used += used;
 463         dl->dl_phys->dl_comp += comp;
 464         dl->dl_phys->dl_uncomp += uncomp;
 465
 466         dle_tofind.dle_mintxg = birth;
 467         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 468         if (dle == NULL)
 469                 dle = avl_nearest(&dl->dl_tree, where, AVL_BEFORE);
 470         dle_enqueue_subobj(dl, dle, obj, tx);
 471 }
 472
 473 static int
 474 dsl_deadlist_insert_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
 475 {
 476         dsl_deadlist_t *dl = arg;
 477         dsl_deadlist_insert(dl, bp, tx);
 478         return (0);
 479 }
 480
 481 /*
 482  * Merge the deadlist pointed to by 'obj' into dl.  obj will be left as
 483  * an empty deadlist.
 484  */
 485 void
 486 dsl_deadlist_merge(dsl_deadlist_t *dl, uint64_t obj, dmu_tx_t *tx)
 487 {
 488         zap_cursor_t zc;
 489         zap_attribute_t za;
 490         dmu_buf_t *bonus;
 491         dsl_deadlist_phys_t *dlp;
 492         dmu_object_info_t doi;
 493
 494         VERIFY3U(0, ==, dmu_object_info(dl->dl_os, obj, &doi));
 495         if (doi.doi_type == DMU_OT_BPOBJ) {
 496                 bpobj_t bpo;
 497                 VERIFY3U(0, ==, bpobj_open(&bpo, dl->dl_os, obj));
 498                 VERIFY3U(0, ==, bpobj_iterate(&bpo,
 499                     dsl_deadlist_insert_cb, dl, tx));
 500                 bpobj_close(&bpo);
 501                 return;
 502         }
 503
 504         mutex_enter(&dl->dl_lock);
 505         for (zap_cursor_init(&zc, dl->dl_os, obj);
 506             zap_cursor_retrieve(&zc, &za) == 0;
 507             zap_cursor_advance(&zc)) {
 508                 uint64_t mintxg = zfs_strtonum(za.za_name, NULL);
 509                 dsl_deadlist_insert_bpobj(dl, za.za_first_integer, mintxg, tx);
 510                 VERIFY3U(0, ==, zap_remove_int(dl->dl_os, obj, mintxg, tx));
 511         }
 512         zap_cursor_fini(&zc);
 513
 514         VERIFY3U(0, ==, dmu_bonus_hold(dl->dl_os, obj, FTAG, &bonus));
 515         dlp = bonus->db_data;
 516         dmu_buf_will_dirty(bonus, tx);
 517         bzero(dlp, sizeof (*dlp));
 518         dmu_buf_rele(bonus, FTAG);
 519         mutex_exit(&dl->dl_lock);
 520 }
 521
 522 /*
 523  * Remove entries on dl that are >= mintxg, and put them on the bpobj.
 524  */
 525 void
 526 dsl_deadlist_move_bpobj(dsl_deadlist_t *dl, bpobj_t *bpo, uint64_t mintxg,
 527     dmu_tx_t *tx)
 528 {
 529         dsl_deadlist_entry_t dle_tofind;
 530         dsl_deadlist_entry_t *dle;
 531         avl_index_t where;
 532
 533         ASSERT(!dl->dl_oldfmt);
 534
 535         mutex_enter(&dl->dl_lock);
 536         dmu_buf_will_dirty(dl->dl_dbuf, tx);
 537         dsl_deadlist_load_tree(dl);
 538
 539         dle_tofind.dle_mintxg = mintxg;
 540         dle = avl_find(&dl->dl_tree, &dle_tofind, &where);
 541         if (dle == NULL)
 542                 dle = avl_nearest(&dl->dl_tree, where, AVL_AFTER);
 543         while (dle) {
 544                 uint64_t used, comp, uncomp;
 545                 dsl_deadlist_entry_t *dle_next;
 546
 547                 bpobj_enqueue_subobj(bpo, dle->dle_bpobj.bpo_object, tx);
 548
 549                 VERIFY3U(0, ==, bpobj_space(&dle->dle_bpobj,
 550                     &used, &comp, &uncomp));
 551                 ASSERT3U(dl->dl_phys->dl_used, >=, used);
 552                 ASSERT3U(dl->dl_phys->dl_comp, >=, comp);
 553                 ASSERT3U(dl->dl_phys->dl_uncomp, >=, uncomp);
 554                 dl->dl_phys->dl_used -= used;
 555                 dl->dl_phys->dl_comp -= comp;
 556                 dl->dl_phys->dl_uncomp -= uncomp;
 557
 558                 VERIFY3U(0, ==, zap_remove_int(dl->dl_os, dl->dl_object,
 559                     dle->dle_mintxg, tx));
 560
 561                 dle_next = AVL_NEXT(&dl->dl_tree, dle);
 562                 avl_remove(&dl->dl_tree, dle);
 563                 bpobj_close(&dle->dle_bpobj);
 564                 kmem_free(dle, sizeof (*dle));
 565                 dle = dle_next;
 566         }
 567         mutex_exit(&dl->dl_lock);
 568 }