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4374 dn_free_ranges should use range_tree_t
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com
Reviewed by: Garrett D'Amore <garrett@damore.org>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>


   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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright (c) 2013 by Delphix. All rights reserved.
  25  */
  26 
  27 #include <sys/zfs_context.h>
  28 #include <sys/dbuf.h>
  29 #include <sys/dnode.h>
  30 #include <sys/dmu.h>
  31 #include <sys/dmu_tx.h>
  32 #include <sys/dmu_objset.h>
  33 #include <sys/dsl_dataset.h>
  34 #include <sys/spa.h>

  35 #include <sys/zfeature.h>
  36 
  37 static void
  38 dnode_increase_indirection(dnode_t *dn, dmu_tx_t *tx)
  39 {
  40         dmu_buf_impl_t *db;
  41         int txgoff = tx->tx_txg & TXG_MASK;
  42         int nblkptr = dn->dn_phys->dn_nblkptr;
  43         int old_toplvl = dn->dn_phys->dn_nlevels - 1;
  44         int new_level = dn->dn_next_nlevels[txgoff];
  45         int i;
  46 
  47         rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
  48 
  49         /* this dnode can't be paged out because it's dirty */
  50         ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE);
  51         ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock));
  52         ASSERT(new_level > 1 && dn->dn_phys->dn_nlevels > 0);
  53 
  54         db = dbuf_hold_level(dn, dn->dn_phys->dn_nlevels, 0, FTAG);


 301                 /* didn't find any non-holes */
 302                 bzero(db->db.db_data, db->db.db_size);
 303                 free_blocks(dn, db->db_blkptr, 1, tx);
 304         } else {
 305                 /*
 306                  * Partial block free; must be marked dirty so that it
 307                  * will be written out.
 308                  */
 309                 ASSERT(db->db_dirtycnt > 0);
 310         }
 311 
 312         DB_DNODE_EXIT(db);
 313         arc_buf_freeze(db->db_buf);
 314 }
 315 
 316 /*
 317  * Traverse the indicated range of the provided file
 318  * and "free" all the blocks contained there.
 319  */
 320 static void
 321 dnode_sync_free_range(dnode_t *dn, uint64_t blkid, uint64_t nblks,
 322     dmu_tx_t *tx)
 323 {
 324         blkptr_t *bp = dn->dn_phys->dn_blkptr;
 325         int dnlevel = dn->dn_phys->dn_nlevels;
 326         boolean_t trunc = B_FALSE;
 327 
 328         if (blkid > dn->dn_phys->dn_maxblkid)
 329                 return;
 330 
 331         ASSERT(dn->dn_phys->dn_maxblkid < UINT64_MAX);
 332         if (blkid + nblks > dn->dn_phys->dn_maxblkid) {
 333                 nblks = dn->dn_phys->dn_maxblkid - blkid + 1;
 334                 trunc = B_TRUE;
 335         }
 336 
 337         /* There are no indirect blocks in the object */
 338         if (dnlevel == 1) {
 339                 if (blkid >= dn->dn_phys->dn_nblkptr) {
 340                         /* this range was never made persistent */
 341                         return;


 359                             TRUE, FTAG, &db));
 360                         rw_exit(&dn->dn_struct_rwlock);
 361 
 362                         free_children(db, blkid, nblks, tx);
 363                         dbuf_rele(db, FTAG);
 364 
 365                 }
 366         }
 367 
 368         if (trunc) {
 369                 dn->dn_phys->dn_maxblkid = blkid == 0 ? 0 : blkid - 1;
 370 
 371                 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) *
 372                     (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 373                 ASSERT(off < dn->dn_phys->dn_maxblkid ||
 374                     dn->dn_phys->dn_maxblkid == 0 ||
 375                     dnode_next_offset(dn, 0, &off, 1, 1, 0) != 0);
 376         }
 377 }
 378 
















 379 /*
 380  * Try to kick all the dnode's dbufs out of the cache...
 381  */
 382 void
 383 dnode_evict_dbufs(dnode_t *dn)
 384 {
 385         int progress;
 386         int pass = 0;
 387 
 388         do {
 389                 dmu_buf_impl_t *db, marker;
 390                 int evicting = FALSE;
 391 
 392                 progress = FALSE;
 393                 mutex_enter(&dn->dn_dbufs_mtx);
 394                 list_insert_tail(&dn->dn_dbufs, &marker);
 395                 db = list_head(&dn->dn_dbufs);
 396                 for (; db != &marker; db = list_head(&dn->dn_dbufs)) {
 397                         list_remove(&dn->dn_dbufs, db);
 398                         list_insert_tail(&dn->dn_dbufs, db);


 516         dn->dn_allocated_txg = 0;
 517         dn->dn_free_txg = 0;
 518         dn->dn_have_spill = B_FALSE;
 519         mutex_exit(&dn->dn_mtx);
 520 
 521         ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT);
 522 
 523         dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg);
 524         /*
 525          * Now that we've released our hold, the dnode may
 526          * be evicted, so we musn't access it.
 527          */
 528 }
 529 
 530 /*
 531  * Write out the dnode's dirty buffers.
 532  */
 533 void
 534 dnode_sync(dnode_t *dn, dmu_tx_t *tx)
 535 {
 536         free_range_t *rp;
 537         dnode_phys_t *dnp = dn->dn_phys;
 538         int txgoff = tx->tx_txg & TXG_MASK;
 539         list_t *list = &dn->dn_dirty_records[txgoff];
 540         static const dnode_phys_t zerodn = { 0 };
 541         boolean_t kill_spill = B_FALSE;
 542 
 543         ASSERT(dmu_tx_is_syncing(tx));
 544         ASSERT(dnp->dn_type != DMU_OT_NONE || dn->dn_allocated_txg);
 545         ASSERT(dnp->dn_type != DMU_OT_NONE ||
 546             bcmp(dnp, &zerodn, DNODE_SIZE) == 0);
 547         DNODE_VERIFY(dn);
 548 
 549         ASSERT(dn->dn_dbuf == NULL || arc_released(dn->dn_dbuf->db_buf));
 550 
 551         if (dmu_objset_userused_enabled(dn->dn_objset) &&
 552             !DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
 553                 mutex_enter(&dn->dn_mtx);
 554                 dn->dn_oldused = DN_USED_BYTES(dn->dn_phys);
 555                 dn->dn_oldflags = dn->dn_phys->dn_flags;
 556                 dn->dn_phys->dn_flags |= DNODE_FLAG_USERUSED_ACCOUNTED;


 574                 dnp->dn_type = dn->dn_type;
 575                 dnp->dn_bonustype = dn->dn_bonustype;
 576                 dnp->dn_bonuslen = dn->dn_bonuslen;
 577         }
 578 
 579         ASSERT(dnp->dn_nlevels > 1 ||
 580             BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 581             BP_GET_LSIZE(&dnp->dn_blkptr[0]) ==
 582             dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 583 
 584         if (dn->dn_next_type[txgoff] != 0) {
 585                 dnp->dn_type = dn->dn_type;
 586                 dn->dn_next_type[txgoff] = 0;
 587         }
 588 
 589         if (dn->dn_next_blksz[txgoff] != 0) {
 590                 ASSERT(P2PHASE(dn->dn_next_blksz[txgoff],
 591                     SPA_MINBLOCKSIZE) == 0);
 592                 ASSERT(BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 593                     dn->dn_maxblkid == 0 || list_head(list) != NULL ||
 594                     avl_last(&dn->dn_ranges[txgoff]) ||
 595                     dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT ==
 596                     dnp->dn_datablkszsec);

 597                 dnp->dn_datablkszsec =
 598                     dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT;
 599                 dn->dn_next_blksz[txgoff] = 0;
 600         }
 601 
 602         if (dn->dn_next_bonuslen[txgoff] != 0) {
 603                 if (dn->dn_next_bonuslen[txgoff] == DN_ZERO_BONUSLEN)
 604                         dnp->dn_bonuslen = 0;
 605                 else
 606                         dnp->dn_bonuslen = dn->dn_next_bonuslen[txgoff];
 607                 ASSERT(dnp->dn_bonuslen <= DN_MAX_BONUSLEN);
 608                 dn->dn_next_bonuslen[txgoff] = 0;
 609         }
 610 
 611         if (dn->dn_next_bonustype[txgoff] != 0) {
 612                 ASSERT(DMU_OT_IS_VALID(dn->dn_next_bonustype[txgoff]));
 613                 dnp->dn_bonustype = dn->dn_next_bonustype[txgoff];
 614                 dn->dn_next_bonustype[txgoff] = 0;
 615         }
 616 


 635         }
 636 
 637         /*
 638          * Just take the live (open-context) values for checksum and compress.
 639          * Strictly speaking it's a future leak, but nothing bad happens if we
 640          * start using the new checksum or compress algorithm a little early.
 641          */
 642         dnp->dn_checksum = dn->dn_checksum;
 643         dnp->dn_compress = dn->dn_compress;
 644 
 645         mutex_exit(&dn->dn_mtx);
 646 
 647         if (kill_spill) {
 648                 free_blocks(dn, &dn->dn_phys->dn_spill, 1, tx);
 649                 mutex_enter(&dn->dn_mtx);
 650                 dnp->dn_flags &= ~DNODE_FLAG_SPILL_BLKPTR;
 651                 mutex_exit(&dn->dn_mtx);
 652         }
 653 
 654         /* process all the "freed" ranges in the file */
 655         while (rp = avl_last(&dn->dn_ranges[txgoff])) {
 656                 dnode_sync_free_range(dn, rp->fr_blkid, rp->fr_nblks, tx);
 657                 /* grab the mutex so we don't race with dnode_block_freed() */

 658                 mutex_enter(&dn->dn_mtx);
 659                 avl_remove(&dn->dn_ranges[txgoff], rp);



 660                 mutex_exit(&dn->dn_mtx);
 661                 kmem_free(rp, sizeof (free_range_t));
 662         }
 663 
 664         if (freeing_dnode) {
 665                 dnode_sync_free(dn, tx);
 666                 return;
 667         }
 668 
 669         if (dn->dn_next_nblkptr[txgoff]) {
 670                 /* this should only happen on a realloc */
 671                 ASSERT(dn->dn_allocated_txg == tx->tx_txg);
 672                 if (dn->dn_next_nblkptr[txgoff] > dnp->dn_nblkptr) {
 673                         /* zero the new blkptrs we are gaining */
 674                         bzero(dnp->dn_blkptr + dnp->dn_nblkptr,
 675                             sizeof (blkptr_t) *
 676                             (dn->dn_next_nblkptr[txgoff] - dnp->dn_nblkptr));
 677 #ifdef ZFS_DEBUG
 678                 } else {
 679                         int i;
 680                         ASSERT(dn->dn_next_nblkptr[txgoff] < dnp->dn_nblkptr);
 681                         /* the blkptrs we are losing better be unallocated */




   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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
  25  */
  26 
  27 #include <sys/zfs_context.h>
  28 #include <sys/dbuf.h>
  29 #include <sys/dnode.h>
  30 #include <sys/dmu.h>
  31 #include <sys/dmu_tx.h>
  32 #include <sys/dmu_objset.h>
  33 #include <sys/dsl_dataset.h>
  34 #include <sys/spa.h>
  35 #include <sys/range_tree.h>
  36 #include <sys/zfeature.h>
  37 
  38 static void
  39 dnode_increase_indirection(dnode_t *dn, dmu_tx_t *tx)
  40 {
  41         dmu_buf_impl_t *db;
  42         int txgoff = tx->tx_txg & TXG_MASK;
  43         int nblkptr = dn->dn_phys->dn_nblkptr;
  44         int old_toplvl = dn->dn_phys->dn_nlevels - 1;
  45         int new_level = dn->dn_next_nlevels[txgoff];
  46         int i;
  47 
  48         rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
  49 
  50         /* this dnode can't be paged out because it's dirty */
  51         ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE);
  52         ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock));
  53         ASSERT(new_level > 1 && dn->dn_phys->dn_nlevels > 0);
  54 
  55         db = dbuf_hold_level(dn, dn->dn_phys->dn_nlevels, 0, FTAG);


 302                 /* didn't find any non-holes */
 303                 bzero(db->db.db_data, db->db.db_size);
 304                 free_blocks(dn, db->db_blkptr, 1, tx);
 305         } else {
 306                 /*
 307                  * Partial block free; must be marked dirty so that it
 308                  * will be written out.
 309                  */
 310                 ASSERT(db->db_dirtycnt > 0);
 311         }
 312 
 313         DB_DNODE_EXIT(db);
 314         arc_buf_freeze(db->db_buf);
 315 }
 316 
 317 /*
 318  * Traverse the indicated range of the provided file
 319  * and "free" all the blocks contained there.
 320  */
 321 static void
 322 dnode_sync_free_range_impl(dnode_t *dn, uint64_t blkid, uint64_t nblks,
 323     dmu_tx_t *tx)
 324 {
 325         blkptr_t *bp = dn->dn_phys->dn_blkptr;
 326         int dnlevel = dn->dn_phys->dn_nlevels;
 327         boolean_t trunc = B_FALSE;
 328 
 329         if (blkid > dn->dn_phys->dn_maxblkid)
 330                 return;
 331 
 332         ASSERT(dn->dn_phys->dn_maxblkid < UINT64_MAX);
 333         if (blkid + nblks > dn->dn_phys->dn_maxblkid) {
 334                 nblks = dn->dn_phys->dn_maxblkid - blkid + 1;
 335                 trunc = B_TRUE;
 336         }
 337 
 338         /* There are no indirect blocks in the object */
 339         if (dnlevel == 1) {
 340                 if (blkid >= dn->dn_phys->dn_nblkptr) {
 341                         /* this range was never made persistent */
 342                         return;


 360                             TRUE, FTAG, &db));
 361                         rw_exit(&dn->dn_struct_rwlock);
 362 
 363                         free_children(db, blkid, nblks, tx);
 364                         dbuf_rele(db, FTAG);
 365 
 366                 }
 367         }
 368 
 369         if (trunc) {
 370                 dn->dn_phys->dn_maxblkid = blkid == 0 ? 0 : blkid - 1;
 371 
 372                 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) *
 373                     (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 374                 ASSERT(off < dn->dn_phys->dn_maxblkid ||
 375                     dn->dn_phys->dn_maxblkid == 0 ||
 376                     dnode_next_offset(dn, 0, &off, 1, 1, 0) != 0);
 377         }
 378 }
 379 
 380 typedef struct dnode_sync_free_range_arg {
 381         dnode_t *dsfra_dnode;
 382         dmu_tx_t *dsfra_tx;
 383 } dnode_sync_free_range_arg_t;
 384 
 385 static void
 386 dnode_sync_free_range(void *arg, uint64_t blkid, uint64_t nblks)
 387 {
 388         dnode_sync_free_range_arg_t *dsfra = arg;
 389         dnode_t *dn = dsfra->dsfra_dnode;
 390 
 391         mutex_exit(&dn->dn_mtx);
 392         dnode_sync_free_range_impl(dn, blkid, nblks, dsfra->dsfra_tx);
 393         mutex_enter(&dn->dn_mtx);
 394 }
 395 
 396 /*
 397  * Try to kick all the dnode's dbufs out of the cache...
 398  */
 399 void
 400 dnode_evict_dbufs(dnode_t *dn)
 401 {
 402         int progress;
 403         int pass = 0;
 404 
 405         do {
 406                 dmu_buf_impl_t *db, marker;
 407                 int evicting = FALSE;
 408 
 409                 progress = FALSE;
 410                 mutex_enter(&dn->dn_dbufs_mtx);
 411                 list_insert_tail(&dn->dn_dbufs, &marker);
 412                 db = list_head(&dn->dn_dbufs);
 413                 for (; db != &marker; db = list_head(&dn->dn_dbufs)) {
 414                         list_remove(&dn->dn_dbufs, db);
 415                         list_insert_tail(&dn->dn_dbufs, db);


 533         dn->dn_allocated_txg = 0;
 534         dn->dn_free_txg = 0;
 535         dn->dn_have_spill = B_FALSE;
 536         mutex_exit(&dn->dn_mtx);
 537 
 538         ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT);
 539 
 540         dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg);
 541         /*
 542          * Now that we've released our hold, the dnode may
 543          * be evicted, so we musn't access it.
 544          */
 545 }
 546 
 547 /*
 548  * Write out the dnode's dirty buffers.
 549  */
 550 void
 551 dnode_sync(dnode_t *dn, dmu_tx_t *tx)
 552 {

 553         dnode_phys_t *dnp = dn->dn_phys;
 554         int txgoff = tx->tx_txg & TXG_MASK;
 555         list_t *list = &dn->dn_dirty_records[txgoff];
 556         static const dnode_phys_t zerodn = { 0 };
 557         boolean_t kill_spill = B_FALSE;
 558 
 559         ASSERT(dmu_tx_is_syncing(tx));
 560         ASSERT(dnp->dn_type != DMU_OT_NONE || dn->dn_allocated_txg);
 561         ASSERT(dnp->dn_type != DMU_OT_NONE ||
 562             bcmp(dnp, &zerodn, DNODE_SIZE) == 0);
 563         DNODE_VERIFY(dn);
 564 
 565         ASSERT(dn->dn_dbuf == NULL || arc_released(dn->dn_dbuf->db_buf));
 566 
 567         if (dmu_objset_userused_enabled(dn->dn_objset) &&
 568             !DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
 569                 mutex_enter(&dn->dn_mtx);
 570                 dn->dn_oldused = DN_USED_BYTES(dn->dn_phys);
 571                 dn->dn_oldflags = dn->dn_phys->dn_flags;
 572                 dn->dn_phys->dn_flags |= DNODE_FLAG_USERUSED_ACCOUNTED;


 590                 dnp->dn_type = dn->dn_type;
 591                 dnp->dn_bonustype = dn->dn_bonustype;
 592                 dnp->dn_bonuslen = dn->dn_bonuslen;
 593         }
 594 
 595         ASSERT(dnp->dn_nlevels > 1 ||
 596             BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 597             BP_GET_LSIZE(&dnp->dn_blkptr[0]) ==
 598             dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 599 
 600         if (dn->dn_next_type[txgoff] != 0) {
 601                 dnp->dn_type = dn->dn_type;
 602                 dn->dn_next_type[txgoff] = 0;
 603         }
 604 
 605         if (dn->dn_next_blksz[txgoff] != 0) {
 606                 ASSERT(P2PHASE(dn->dn_next_blksz[txgoff],
 607                     SPA_MINBLOCKSIZE) == 0);
 608                 ASSERT(BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 609                     dn->dn_maxblkid == 0 || list_head(list) != NULL ||

 610                     dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT ==
 611                     dnp->dn_datablkszsec ||
 612                     range_tree_space(dn->dn_free_ranges[txgoff]) != 0);
 613                 dnp->dn_datablkszsec =
 614                     dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT;
 615                 dn->dn_next_blksz[txgoff] = 0;
 616         }
 617 
 618         if (dn->dn_next_bonuslen[txgoff] != 0) {
 619                 if (dn->dn_next_bonuslen[txgoff] == DN_ZERO_BONUSLEN)
 620                         dnp->dn_bonuslen = 0;
 621                 else
 622                         dnp->dn_bonuslen = dn->dn_next_bonuslen[txgoff];
 623                 ASSERT(dnp->dn_bonuslen <= DN_MAX_BONUSLEN);
 624                 dn->dn_next_bonuslen[txgoff] = 0;
 625         }
 626 
 627         if (dn->dn_next_bonustype[txgoff] != 0) {
 628                 ASSERT(DMU_OT_IS_VALID(dn->dn_next_bonustype[txgoff]));
 629                 dnp->dn_bonustype = dn->dn_next_bonustype[txgoff];
 630                 dn->dn_next_bonustype[txgoff] = 0;
 631         }
 632 


 651         }
 652 
 653         /*
 654          * Just take the live (open-context) values for checksum and compress.
 655          * Strictly speaking it's a future leak, but nothing bad happens if we
 656          * start using the new checksum or compress algorithm a little early.
 657          */
 658         dnp->dn_checksum = dn->dn_checksum;
 659         dnp->dn_compress = dn->dn_compress;
 660 
 661         mutex_exit(&dn->dn_mtx);
 662 
 663         if (kill_spill) {
 664                 free_blocks(dn, &dn->dn_phys->dn_spill, 1, tx);
 665                 mutex_enter(&dn->dn_mtx);
 666                 dnp->dn_flags &= ~DNODE_FLAG_SPILL_BLKPTR;
 667                 mutex_exit(&dn->dn_mtx);
 668         }
 669 
 670         /* process all the "freed" ranges in the file */
 671         if (dn->dn_free_ranges[txgoff] != NULL) {
 672                 dnode_sync_free_range_arg_t dsfra;
 673                 dsfra.dsfra_dnode = dn;
 674                 dsfra.dsfra_tx = tx;
 675                 mutex_enter(&dn->dn_mtx);
 676                 range_tree_vacate(dn->dn_free_ranges[txgoff],
 677                     dnode_sync_free_range, &dsfra);
 678                 range_tree_destroy(dn->dn_free_ranges[txgoff]);
 679                 dn->dn_free_ranges[txgoff] = NULL;
 680                 mutex_exit(&dn->dn_mtx);

 681         }
 682 
 683         if (freeing_dnode) {
 684                 dnode_sync_free(dn, tx);
 685                 return;
 686         }
 687 
 688         if (dn->dn_next_nblkptr[txgoff]) {
 689                 /* this should only happen on a realloc */
 690                 ASSERT(dn->dn_allocated_txg == tx->tx_txg);
 691                 if (dn->dn_next_nblkptr[txgoff] > dnp->dn_nblkptr) {
 692                         /* zero the new blkptrs we are gaining */
 693                         bzero(dnp->dn_blkptr + dnp->dn_nblkptr,
 694                             sizeof (blkptr_t) *
 695                             (dn->dn_next_nblkptr[txgoff] - dnp->dn_nblkptr));
 696 #ifdef ZFS_DEBUG
 697                 } else {
 698                         int i;
 699                         ASSERT(dn->dn_next_nblkptr[txgoff] < dnp->dn_nblkptr);
 700                         /* the blkptrs we are losing better be unallocated */