usr/src/uts/common/fs/zfs/dnode_sync.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 (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);
  56         ASSERT(db != NULL);
  57
  58         dn->dn_phys->dn_nlevels = new_level;
  59         dprintf("os=%p obj=%llu, increase to %d\n", dn->dn_objset,
  60             dn->dn_object, dn->dn_phys->dn_nlevels);
  61
  62         /* check for existing blkptrs in the dnode */
  63         for (i = 0; i < nblkptr; i++)
  64                 if (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[i]))
  65                         break;
  66         if (i != nblkptr) {
  67                 /* transfer dnode's block pointers to new indirect block */
  68                 (void) dbuf_read(db, NULL, DB_RF_MUST_SUCCEED|DB_RF_HAVESTRUCT);
  69                 ASSERT(db->db.db_data);
  70                 ASSERT(arc_released(db->db_buf));
  71                 ASSERT3U(sizeof (blkptr_t) * nblkptr, <=, db->db.db_size);
  72                 bcopy(dn->dn_phys->dn_blkptr, db->db.db_data,
  73                     sizeof (blkptr_t) * nblkptr);
  74                 arc_buf_freeze(db->db_buf);
  75         }
  76
  77         /* set dbuf's parent pointers to new indirect buf */
  78         for (i = 0; i < nblkptr; i++) {
  79                 dmu_buf_impl_t *child = dbuf_find(dn, old_toplvl, i);
  80
  81                 if (child == NULL)
  82                         continue;
  83 #ifdef  DEBUG
  84                 DB_DNODE_ENTER(child);
  85                 ASSERT3P(DB_DNODE(child), ==, dn);
  86                 DB_DNODE_EXIT(child);
  87 #endif  /* DEBUG */
  88                 if (child->db_parent && child->db_parent != dn->dn_dbuf) {
  89                         ASSERT(child->db_parent->db_level == db->db_level);
  90                         ASSERT(child->db_blkptr !=
  91                             &dn->dn_phys->dn_blkptr[child->db_blkid]);
  92                         mutex_exit(&child->db_mtx);
  93                         continue;
  94                 }
  95                 ASSERT(child->db_parent == NULL ||
  96                     child->db_parent == dn->dn_dbuf);
  97
  98                 child->db_parent = db;
  99                 dbuf_add_ref(db, child);
 100                 if (db->db.db_data)
 101                         child->db_blkptr = (blkptr_t *)db->db.db_data + i;
 102                 else
 103                         child->db_blkptr = NULL;
 104                 dprintf_dbuf_bp(child, child->db_blkptr,
 105                     "changed db_blkptr to new indirect %s", "");
 106
 107                 mutex_exit(&child->db_mtx);
 108         }
 109
 110         bzero(dn->dn_phys->dn_blkptr, sizeof (blkptr_t) * nblkptr);
 111
 112         dbuf_rele(db, FTAG);
 113
 114         rw_exit(&dn->dn_struct_rwlock);
 115 }
 116
 117 static void
 118 free_blocks(dnode_t *dn, blkptr_t *bp, int num, dmu_tx_t *tx)
 119 {
 120         dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
 121         uint64_t bytesfreed = 0;
 122
 123         dprintf("ds=%p obj=%llx num=%d\n", ds, dn->dn_object, num);
 124
 125         for (int i = 0; i < num; i++, bp++) {
 126                 if (BP_IS_HOLE(bp))
 127                         continue;
 128
 129                 bytesfreed += dsl_dataset_block_kill(ds, bp, tx, B_FALSE);
 130                 ASSERT3U(bytesfreed, <=, DN_USED_BYTES(dn->dn_phys));
 131
 132                 /*
 133                  * Save some useful information on the holes being
 134                  * punched, including logical size, type, and indirection
 135                  * level. Retaining birth time enables detection of when
 136                  * holes are punched for reducing the number of free
 137                  * records transmitted during a zfs send.
 138                  */
 139
 140                 uint64_t lsize = BP_GET_LSIZE(bp);
 141                 dmu_object_type_t type = BP_GET_TYPE(bp);
 142                 uint64_t lvl = BP_GET_LEVEL(bp);
 143
 144                 bzero(bp, sizeof (blkptr_t));
 145
 146                 if (spa_feature_is_active(dn->dn_objset->os_spa,
 147                     SPA_FEATURE_HOLE_BIRTH)) {
 148                         BP_SET_LSIZE(bp, lsize);
 149                         BP_SET_TYPE(bp, type);
 150                         BP_SET_LEVEL(bp, lvl);
 151                         BP_SET_BIRTH(bp, dmu_tx_get_txg(tx), 0);
 152                 }
 153         }
 154         dnode_diduse_space(dn, -bytesfreed);
 155 }
 156
 157 #ifdef ZFS_DEBUG
 158 static void
 159 free_verify(dmu_buf_impl_t *db, uint64_t start, uint64_t end, dmu_tx_t *tx)
 160 {
 161         int off, num;
 162         int i, err, epbs;
 163         uint64_t txg = tx->tx_txg;
 164         dnode_t *dn;
 165
 166         DB_DNODE_ENTER(db);
 167         dn = DB_DNODE(db);
 168         epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT;
 169         off = start - (db->db_blkid * 1<<epbs);
 170         num = end - start + 1;
 171
 172         ASSERT3U(off, >=, 0);
 173         ASSERT3U(num, >=, 0);
 174         ASSERT3U(db->db_level, >, 0);
 175         ASSERT3U(db->db.db_size, ==, 1 << dn->dn_phys->dn_indblkshift);
 176         ASSERT3U(off+num, <=, db->db.db_size >> SPA_BLKPTRSHIFT);
 177         ASSERT(db->db_blkptr != NULL);
 178
 179         for (i = off; i < off+num; i++) {
 180                 uint64_t *buf;
 181                 dmu_buf_impl_t *child;
 182                 dbuf_dirty_record_t *dr;
 183                 int j;
 184
 185                 ASSERT(db->db_level == 1);
 186
 187                 rw_enter(&dn->dn_struct_rwlock, RW_READER);
 188                 err = dbuf_hold_impl(dn, db->db_level-1,
 189                     (db->db_blkid << epbs) + i, TRUE, FTAG, &child);
 190                 rw_exit(&dn->dn_struct_rwlock);
 191                 if (err == ENOENT)
 192                         continue;
 193                 ASSERT(err == 0);
 194                 ASSERT(child->db_level == 0);
 195                 dr = child->db_last_dirty;
 196                 while (dr && dr->dr_txg > txg)
 197                         dr = dr->dr_next;
 198                 ASSERT(dr == NULL || dr->dr_txg == txg);
 199
 200                 /* data_old better be zeroed */
 201                 if (dr) {
 202                         buf = dr->dt.dl.dr_data->b_data;
 203                         for (j = 0; j < child->db.db_size >> 3; j++) {
 204                                 if (buf[j] != 0) {
 205                                         panic("freed data not zero: "
 206                                             "child=%p i=%d off=%d num=%d\n",
 207                                             (void *)child, i, off, num);
 208                                 }
 209                         }
 210                 }
 211
 212                 /*
 213                  * db_data better be zeroed unless it's dirty in a
 214                  * future txg.
 215                  */
 216                 mutex_enter(&child->db_mtx);
 217                 buf = child->db.db_data;
 218                 if (buf != NULL && child->db_state != DB_FILL &&
 219                     child->db_last_dirty == NULL) {
 220                         for (j = 0; j < child->db.db_size >> 3; j++) {
 221                                 if (buf[j] != 0) {
 222                                         panic("freed data not zero: "
 223                                             "child=%p i=%d off=%d num=%d\n",
 224                                             (void *)child, i, off, num);
 225                                 }
 226                         }
 227                 }
 228                 mutex_exit(&child->db_mtx);
 229
 230                 dbuf_rele(child, FTAG);
 231         }
 232         DB_DNODE_EXIT(db);
 233 }
 234 #endif
 235
 236 static void
 237 free_children(dmu_buf_impl_t *db, uint64_t blkid, uint64_t nblks,
 238     dmu_tx_t *tx)
 239 {
 240         dnode_t *dn;
 241         blkptr_t *bp;
 242         dmu_buf_impl_t *subdb;
 243         uint64_t start, end, dbstart, dbend, i;
 244         int epbs, shift;
 245
 246         /*
 247          * There is a small possibility that this block will not be cached:
 248          *   1 - if level > 1 and there are no children with level <= 1
 249          *   2 - if this block was evicted since we read it from
 250          *       dmu_tx_hold_free().
 251          */
 252         if (db->db_state != DB_CACHED)
 253                 (void) dbuf_read(db, NULL, DB_RF_MUST_SUCCEED);
 254
 255         dbuf_release_bp(db);
 256         bp = db->db.db_data;
 257
 258         DB_DNODE_ENTER(db);
 259         dn = DB_DNODE(db);
 260         epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT;
 261         shift = (db->db_level - 1) * epbs;
 262         dbstart = db->db_blkid << epbs;
 263         start = blkid >> shift;
 264         if (dbstart < start) {
 265                 bp += start - dbstart;
 266         } else {
 267                 start = dbstart;
 268         }
 269         dbend = ((db->db_blkid + 1) << epbs) - 1;
 270         end = (blkid + nblks - 1) >> shift;
 271         if (dbend <= end)
 272                 end = dbend;
 273
 274         ASSERT3U(start, <=, end);
 275
 276         if (db->db_level == 1) {
 277                 FREE_VERIFY(db, start, end, tx);
 278                 free_blocks(dn, bp, end-start+1, tx);
 279         } else {
 280                 for (i = start; i <= end; i++, bp++) {
 281                         if (BP_IS_HOLE(bp))
 282                                 continue;
 283                         rw_enter(&dn->dn_struct_rwlock, RW_READER);
 284                         VERIFY0(dbuf_hold_impl(dn, db->db_level - 1,
 285                             i, B_TRUE, FTAG, &subdb));
 286                         rw_exit(&dn->dn_struct_rwlock);
 287                         ASSERT3P(bp, ==, subdb->db_blkptr);
 288
 289                         free_children(subdb, blkid, nblks, tx);
 290                         dbuf_rele(subdb, FTAG);
 291                 }
 292         }
 293
 294         /* If this whole block is free, free ourself too. */
 295         for (i = 0, bp = db->db.db_data; i < 1 << epbs; i++, bp++) {
 296                 if (!BP_IS_HOLE(bp))
 297                         break;
 298         }
 299         if (i == 1 << epbs) {
 300                 /* didn't find any non-holes */
 301                 bzero(db->db.db_data, db->db.db_size);
 302                 free_blocks(dn, db->db_blkptr, 1, tx);
 303         } else {
 304                 /*
 305                  * Partial block free; must be marked dirty so that it
 306                  * will be written out.
 307                  */
 308                 ASSERT(db->db_dirtycnt > 0);
 309         }
 310
 311         DB_DNODE_EXIT(db);
 312         arc_buf_freeze(db->db_buf);
 313 }
 314
 315 /*
 316  * Traverse the indicated range of the provided file
 317  * and "free" all the blocks contained there.
 318  */
 319 static void
 320 dnode_sync_free_range_impl(dnode_t *dn, uint64_t blkid, uint64_t nblks,
 321     dmu_tx_t *tx)
 322 {
 323         blkptr_t *bp = dn->dn_phys->dn_blkptr;
 324         int dnlevel = dn->dn_phys->dn_nlevels;
 325         boolean_t trunc = B_FALSE;
 326
 327         if (blkid > dn->dn_phys->dn_maxblkid)
 328                 return;
 329
 330         ASSERT(dn->dn_phys->dn_maxblkid < UINT64_MAX);
 331         if (blkid + nblks > dn->dn_phys->dn_maxblkid) {
 332                 nblks = dn->dn_phys->dn_maxblkid - blkid + 1;
 333                 trunc = B_TRUE;
 334         }
 335
 336         /* There are no indirect blocks in the object */
 337         if (dnlevel == 1) {
 338                 if (blkid >= dn->dn_phys->dn_nblkptr) {
 339                         /* this range was never made persistent */
 340                         return;
 341                 }
 342                 ASSERT3U(blkid + nblks, <=, dn->dn_phys->dn_nblkptr);
 343                 free_blocks(dn, bp + blkid, nblks, tx);
 344         } else {
 345                 int shift = (dnlevel - 1) *
 346                     (dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT);
 347                 int start = blkid >> shift;
 348                 int end = (blkid + nblks - 1) >> shift;
 349                 dmu_buf_impl_t *db;
 350
 351                 ASSERT(start < dn->dn_phys->dn_nblkptr);
 352                 bp += start;
 353                 for (int i = start; i <= end; i++, bp++) {
 354                         if (BP_IS_HOLE(bp))
 355                                 continue;
 356                         rw_enter(&dn->dn_struct_rwlock, RW_READER);
 357                         VERIFY0(dbuf_hold_impl(dn, dnlevel - 1, i,
 358                             TRUE, FTAG, &db));
 359                         rw_exit(&dn->dn_struct_rwlock);
 360
 361                         free_children(db, blkid, nblks, tx);
 362                         dbuf_rele(db, FTAG);
 363                 }
 364         }
 365
 366         if (trunc) {
 367                 dn->dn_phys->dn_maxblkid = blkid == 0 ? 0 : blkid - 1;
 368
 369                 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) *
 370                     (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 371                 ASSERT(off < dn->dn_phys->dn_maxblkid ||
 372                     dn->dn_phys->dn_maxblkid == 0 ||
 373                     dnode_next_offset(dn, 0, &off, 1, 1, 0) != 0);
 374         }
 375 }
 376
 377 typedef struct dnode_sync_free_range_arg {
 378         dnode_t *dsfra_dnode;
 379         dmu_tx_t *dsfra_tx;
 380 } dnode_sync_free_range_arg_t;
 381
 382 static void
 383 dnode_sync_free_range(void *arg, uint64_t blkid, uint64_t nblks)
 384 {
 385         dnode_sync_free_range_arg_t *dsfra = arg;
 386         dnode_t *dn = dsfra->dsfra_dnode;
 387
 388         mutex_exit(&dn->dn_mtx);
 389         dnode_sync_free_range_impl(dn, blkid, nblks, dsfra->dsfra_tx);
 390         mutex_enter(&dn->dn_mtx);
 391 }
 392
 393 /*
 394  * Try to kick all the dnode's dbufs out of the cache...
 395  */
 396 void
 397 dnode_evict_dbufs(dnode_t *dn)
 398 {
 399         int progress;
 400         int pass = 0;
 401
 402         do {
 403                 dmu_buf_impl_t *db, marker;
 404                 int evicting = FALSE;
 405
 406                 progress = FALSE;
 407                 mutex_enter(&dn->dn_dbufs_mtx);
 408                 list_insert_tail(&dn->dn_dbufs, &marker);
 409                 db = list_head(&dn->dn_dbufs);
 410                 for (; db != &marker; db = list_head(&dn->dn_dbufs)) {
 411                         list_remove(&dn->dn_dbufs, db);
 412                         list_insert_tail(&dn->dn_dbufs, db);
 413 #ifdef  DEBUG
 414                         DB_DNODE_ENTER(db);
 415                         ASSERT3P(DB_DNODE(db), ==, dn);
 416                         DB_DNODE_EXIT(db);
 417 #endif  /* DEBUG */
 418
 419                         mutex_enter(&db->db_mtx);
 420                         if (db->db_state == DB_EVICTING) {
 421                                 progress = TRUE;
 422                                 evicting = TRUE;
 423                                 mutex_exit(&db->db_mtx);
 424                         } else if (refcount_is_zero(&db->db_holds)) {
 425                                 progress = TRUE;
 426                                 dbuf_clear(db); /* exits db_mtx for us */
 427                         } else {
 428                                 mutex_exit(&db->db_mtx);
 429                         }
 430
 431                 }
 432                 list_remove(&dn->dn_dbufs, &marker);
 433                 /*
 434                  * NB: we need to drop dn_dbufs_mtx between passes so
 435                  * that any DB_EVICTING dbufs can make progress.
 436                  * Ideally, we would have some cv we could wait on, but
 437                  * since we don't, just wait a bit to give the other
 438                  * thread a chance to run.
 439                  */
 440                 mutex_exit(&dn->dn_dbufs_mtx);
 441                 if (evicting)
 442                         delay(1);
 443                 pass++;
 444                 ASSERT(pass < 100); /* sanity check */
 445         } while (progress);
 446
 447         rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
 448         if (dn->dn_bonus && refcount_is_zero(&dn->dn_bonus->db_holds)) {
 449                 mutex_enter(&dn->dn_bonus->db_mtx);
 450                 dbuf_evict(dn->dn_bonus);
 451                 dn->dn_bonus = NULL;
 452         }
 453         rw_exit(&dn->dn_struct_rwlock);
 454 }
 455
 456 static void
 457 dnode_undirty_dbufs(list_t *list)
 458 {
 459         dbuf_dirty_record_t *dr;
 460
 461         while (dr = list_head(list)) {
 462                 dmu_buf_impl_t *db = dr->dr_dbuf;
 463                 uint64_t txg = dr->dr_txg;
 464
 465                 if (db->db_level != 0)
 466                         dnode_undirty_dbufs(&dr->dt.di.dr_children);
 467
 468                 mutex_enter(&db->db_mtx);
 469                 /* XXX - use dbuf_undirty()? */
 470                 list_remove(list, dr);
 471                 ASSERT(db->db_last_dirty == dr);
 472                 db->db_last_dirty = NULL;
 473                 db->db_dirtycnt -= 1;
 474                 if (db->db_level == 0) {
 475                         ASSERT(db->db_blkid == DMU_BONUS_BLKID ||
 476                             dr->dt.dl.dr_data == db->db_buf);
 477                         dbuf_unoverride(dr);
 478                 }
 479                 kmem_free(dr, sizeof (dbuf_dirty_record_t));
 480                 dbuf_rele_and_unlock(db, (void *)(uintptr_t)txg);
 481         }
 482 }
 483
 484 static void
 485 dnode_sync_free(dnode_t *dn, dmu_tx_t *tx)
 486 {
 487         int txgoff = tx->tx_txg & TXG_MASK;
 488
 489         ASSERT(dmu_tx_is_syncing(tx));
 490
 491         /*
 492          * Our contents should have been freed in dnode_sync() by the
 493          * free range record inserted by the caller of dnode_free().
 494          */
 495         ASSERT0(DN_USED_BYTES(dn->dn_phys));
 496         ASSERT(BP_IS_HOLE(dn->dn_phys->dn_blkptr));
 497
 498         dnode_undirty_dbufs(&dn->dn_dirty_records[txgoff]);
 499         dnode_evict_dbufs(dn);
 500         ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL);
 501         ASSERT3P(dn->dn_bonus, ==, NULL);
 502
 503         /*
 504          * XXX - It would be nice to assert this, but we may still
 505          * have residual holds from async evictions from the arc...
 506          *
 507          * zfs_obj_to_path() also depends on this being
 508          * commented out.
 509          *
 510          * ASSERT3U(refcount_count(&dn->dn_holds), ==, 1);
 511          */
 512
 513         /* Undirty next bits */
 514         dn->dn_next_nlevels[txgoff] = 0;
 515         dn->dn_next_indblkshift[txgoff] = 0;
 516         dn->dn_next_blksz[txgoff] = 0;
 517
 518         /* ASSERT(blkptrs are zero); */
 519         ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE);
 520         ASSERT(dn->dn_type != DMU_OT_NONE);
 521
 522         ASSERT(dn->dn_free_txg > 0);
 523         if (dn->dn_allocated_txg != dn->dn_free_txg)
 524                 dmu_buf_will_dirty(&dn->dn_dbuf->db, tx);
 525         bzero(dn->dn_phys, sizeof (dnode_phys_t));
 526
 527         mutex_enter(&dn->dn_mtx);
 528         dn->dn_type = DMU_OT_NONE;
 529         dn->dn_maxblkid = 0;
 530         dn->dn_allocated_txg = 0;
 531         dn->dn_free_txg = 0;
 532         dn->dn_have_spill = B_FALSE;
 533         mutex_exit(&dn->dn_mtx);
 534
 535         ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT);
 536
 537         dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg);
 538         /*
 539          * Now that we've released our hold, the dnode may
 540          * be evicted, so we musn't access it.
 541          */
 542 }
 543
 544 /*
 545  * Write out the dnode's dirty buffers.
 546  */
 547 void
 548 dnode_sync(dnode_t *dn, dmu_tx_t *tx)
 549 {
 550         dnode_phys_t *dnp = dn->dn_phys;
 551         int txgoff = tx->tx_txg & TXG_MASK;
 552         list_t *list = &dn->dn_dirty_records[txgoff];
 553         static const dnode_phys_t zerodn = { 0 };
 554         boolean_t kill_spill = B_FALSE;
 555
 556         ASSERT(dmu_tx_is_syncing(tx));
 557         ASSERT(dnp->dn_type != DMU_OT_NONE || dn->dn_allocated_txg);
 558         ASSERT(dnp->dn_type != DMU_OT_NONE ||
 559             bcmp(dnp, &zerodn, DNODE_SIZE) == 0);
 560         DNODE_VERIFY(dn);
 561
 562         ASSERT(dn->dn_dbuf == NULL || arc_released(dn->dn_dbuf->db_buf));
 563
 564         if (dmu_objset_userused_enabled(dn->dn_objset) &&
 565             !DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
 566                 mutex_enter(&dn->dn_mtx);
 567                 dn->dn_oldused = DN_USED_BYTES(dn->dn_phys);
 568                 dn->dn_oldflags = dn->dn_phys->dn_flags;
 569                 dn->dn_phys->dn_flags |= DNODE_FLAG_USERUSED_ACCOUNTED;
 570                 mutex_exit(&dn->dn_mtx);
 571                 dmu_objset_userquota_get_ids(dn, B_FALSE, tx);
 572         } else {
 573                 /* Once we account for it, we should always account for it. */
 574                 ASSERT(!(dn->dn_phys->dn_flags &
 575                     DNODE_FLAG_USERUSED_ACCOUNTED));
 576         }
 577
 578         mutex_enter(&dn->dn_mtx);
 579         if (dn->dn_allocated_txg == tx->tx_txg) {
 580                 /* The dnode is newly allocated or reallocated */
 581                 if (dnp->dn_type == DMU_OT_NONE) {
 582                         /* this is a first alloc, not a realloc */
 583                         dnp->dn_nlevels = 1;
 584                         dnp->dn_nblkptr = dn->dn_nblkptr;
 585                 }
 586
 587                 dnp->dn_type = dn->dn_type;
 588                 dnp->dn_bonustype = dn->dn_bonustype;
 589                 dnp->dn_bonuslen = dn->dn_bonuslen;
 590         }
 591         ASSERT(dnp->dn_nlevels > 1 ||
 592             BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 593             BP_IS_EMBEDDED(&dnp->dn_blkptr[0]) ||
 594             BP_GET_LSIZE(&dnp->dn_blkptr[0]) ==
 595             dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT);
 596         ASSERT(dnp->dn_nlevels < 2 ||
 597             BP_IS_HOLE(&dnp->dn_blkptr[0]) ||
 598             BP_GET_LSIZE(&dnp->dn_blkptr[0]) == 1 << dnp->dn_indblkshift);
 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
 633         boolean_t freeing_dnode = dn->dn_free_txg > 0 &&
 634             dn->dn_free_txg <= tx->tx_txg;
 635
 636         /*
 637          * We will either remove a spill block when a file is being removed
 638          * or we have been asked to remove it.
 639          */
 640         if (dn->dn_rm_spillblk[txgoff] ||
 641             ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) && freeing_dnode)) {
 642                 if ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR))
 643                         kill_spill = B_TRUE;
 644                 dn->dn_rm_spillblk[txgoff] = 0;
 645         }
 646
 647         if (dn->dn_next_indblkshift[txgoff] != 0) {
 648                 ASSERT(dnp->dn_nlevels == 1);
 649                 dnp->dn_indblkshift = dn->dn_next_indblkshift[txgoff];
 650                 dn->dn_next_indblkshift[txgoff] = 0;
 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 */
 701                         for (i = dn->dn_next_nblkptr[txgoff];
 702                             i < dnp->dn_nblkptr; i++)
 703                                 ASSERT(BP_IS_HOLE(&dnp->dn_blkptr[i]));
 704 #endif
 705                 }
 706                 mutex_enter(&dn->dn_mtx);
 707                 dnp->dn_nblkptr = dn->dn_next_nblkptr[txgoff];
 708                 dn->dn_next_nblkptr[txgoff] = 0;
 709                 mutex_exit(&dn->dn_mtx);
 710         }
 711
 712         if (dn->dn_next_nlevels[txgoff]) {
 713                 dnode_increase_indirection(dn, tx);
 714                 dn->dn_next_nlevels[txgoff] = 0;
 715         }
 716
 717         dbuf_sync_list(list, tx);
 718
 719         if (!DMU_OBJECT_IS_SPECIAL(dn->dn_object)) {
 720                 ASSERT3P(list_head(list), ==, NULL);
 721                 dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg);
 722         }
 723
 724         /*
 725          * Although we have dropped our reference to the dnode, it
 726          * can't be evicted until its written, and we haven't yet
 727          * initiated the IO for the dnode's dbuf.
 728          */
 729 }