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 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/dmu.h> 32 #include <sys/dmu_tx.h> 33 #include <sys/dmu_objset.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/spa.h> 36 #include <sys/zio.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 i; 43 uint64_t txg = tx->tx_txg; 44 45 ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE); 46 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 47 /* this dnode can't be paged out because it's dirty */ 48 49 db = dbuf_hold_level(dn, dn->dn_phys->dn_nlevels, 0, FTAG); 50 ASSERT(db != NULL); 51 for (i = 0; i < dn->dn_phys->dn_nblkptr; i++) 52 if (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[i])) 53 break; 54 if (i != dn->dn_phys->dn_nblkptr) { 55 ASSERT(list_link_active(&db->db_dirty_node[txg&TXG_MASK])); 56 57 (void) dbuf_read(db, NULL, 58 DB_RF_HAVESTRUCT | DB_RF_MUST_SUCCEED); 59 arc_release(db->db_buf, db); 60 /* copy dnode's block pointers to new indirect block */ 61 ASSERT3U(sizeof (blkptr_t) * dn->dn_phys->dn_nblkptr, <=, 62 db->db.db_size); 63 bcopy(dn->dn_phys->dn_blkptr, db->db.db_data, 64 sizeof (blkptr_t) * dn->dn_phys->dn_nblkptr); 65 arc_buf_freeze(db->db_buf); 66 } 67 68 dn->dn_phys->dn_nlevels += 1; 69 dprintf("os=%p obj=%llu, increase to %d\n", 70 dn->dn_objset, dn->dn_object, 71 dn->dn_phys->dn_nlevels); 72 73 /* set dbuf's parent pointers to new indirect buf */ 74 for (i = 0; i < dn->dn_phys->dn_nblkptr; i++) { 75 dmu_buf_impl_t *child = 76 dbuf_find(dn, dn->dn_phys->dn_nlevels-2, i); 77 if (child == NULL) 78 continue; 79 if (child->db_dnode == NULL) { 80 mutex_exit(&child->db_mtx); 81 continue; 82 } 83 84 if (child->db_parent == NULL || 85 child->db_parent == dn->dn_dbuf) { 86 dprintf_dbuf_bp(child, child->db_blkptr, 87 "changing db_blkptr to new indirect %s", ""); 88 child->db_parent = db; 89 dbuf_add_ref(db, child); 90 if (db->db.db_data) { 91 child->db_blkptr = 92 (blkptr_t *)db->db.db_data + i; 93 } else { 94 child->db_blkptr = NULL; 95 } 96 dprintf_dbuf_bp(child, child->db_blkptr, 97 "changed db_blkptr to new indirect %s", ""); 98 } 99 ASSERT3P(child->db_parent, ==, db); 100 101 mutex_exit(&child->db_mtx); 102 } 103 104 bzero(dn->dn_phys->dn_blkptr, 105 sizeof (blkptr_t) * dn->dn_phys->dn_nblkptr); 106 107 dbuf_rele(db, FTAG); 108 } 109 110 static void 111 free_blocks(dnode_t *dn, blkptr_t *bp, int num, dmu_tx_t *tx) 112 { 113 objset_impl_t *os = dn->dn_objset; 114 uint64_t bytesfreed = 0; 115 int i; 116 117 dprintf("os=%p obj=%llx num=%d\n", os, dn->dn_object, num); 118 119 for (i = 0; i < num; i++, bp++) { 120 if (BP_IS_HOLE(bp)) 121 continue; 122 123 bytesfreed += bp_get_dasize(os->os_spa, bp); 124 ASSERT3U(bytesfreed, <=, DN_USED_BYTES(dn->dn_phys)); 125 dsl_dataset_block_kill(os->os_dsl_dataset, bp, tx); 126 } 127 dnode_diduse_space(dn, -bytesfreed); 128 } 129 130 #ifdef ZFS_DEBUG 131 static void 132 free_verify(dmu_buf_impl_t *db, uint64_t start, uint64_t end, dmu_tx_t *tx) 133 { 134 int off, num; 135 int i, err, epbs; 136 uint64_t txg = tx->tx_txg; 137 138 epbs = db->db_dnode->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 139 off = start - (db->db_blkid * 1<<epbs); 140 num = end - start + 1; 141 142 ASSERT3U(off, >=, 0); 143 ASSERT3U(num, >=, 0); 144 ASSERT3U(db->db_level, >, 0); 145 ASSERT3U(db->db.db_size, ==, 1<<db->db_dnode->dn_phys->dn_indblkshift); 146 ASSERT3U(off+num, <=, db->db.db_size >> SPA_BLKPTRSHIFT); 147 ASSERT(db->db_blkptr != NULL); 148 149 for (i = off; i < off+num; i++) { 150 uint64_t *buf; 151 int j; 152 dmu_buf_impl_t *child; 153 154 ASSERT(db->db_level == 1); 155 156 rw_enter(&db->db_dnode->dn_struct_rwlock, RW_READER); 157 err = dbuf_hold_impl(db->db_dnode, db->db_level-1, 158 (db->db_blkid << epbs) + i, TRUE, FTAG, &child); 159 rw_exit(&db->db_dnode->dn_struct_rwlock); 160 if (err == ENOENT) 161 continue; 162 ASSERT(err == 0); 163 ASSERT(child->db_level == 0); 164 ASSERT(!list_link_active(&child->db_dirty_node[txg&TXG_MASK])); 165 166 /* db_data_old better be zeroed */ 167 if (child->db_d.db_data_old[txg & TXG_MASK]) { 168 buf = child->db_d.db_data_old[txg & TXG_MASK]->b_data; 169 for (j = 0; j < child->db.db_size >> 3; j++) { 170 if (buf[j] != 0) { 171 panic("freed data not zero: " 172 "child=%p i=%d off=%d num=%d\n", 173 child, i, off, num); 174 } 175 } 176 } 177 178 /* 179 * db_data better be zeroed unless it's dirty in a 180 * future txg. 181 */ 182 mutex_enter(&child->db_mtx); 183 buf = child->db.db_data; 184 if (buf != NULL && child->db_state != DB_FILL && 185 !list_link_active(&child->db_dirty_node 186 [(txg+1) & TXG_MASK]) && 187 !list_link_active(&child->db_dirty_node 188 [(txg+2) & TXG_MASK])) { 189 for (j = 0; j < child->db.db_size >> 3; j++) { 190 if (buf[j] != 0) { 191 panic("freed data not zero: " 192 "child=%p i=%d off=%d num=%d\n", 193 child, i, off, num); 194 } 195 } 196 } 197 mutex_exit(&child->db_mtx); 198 199 dbuf_rele(child, FTAG); 200 } 201 } 202 #endif 203 204 static int 205 free_children(dmu_buf_impl_t *db, uint64_t blkid, uint64_t nblks, int trunc, 206 dmu_tx_t *tx) 207 { 208 dnode_t *dn = db->db_dnode; 209 blkptr_t *bp; 210 dmu_buf_impl_t *subdb; 211 uint64_t start, end, dbstart, dbend, i; 212 int epbs, shift, err; 213 int txgoff = tx->tx_txg & TXG_MASK; 214 int all = TRUE; 215 216 (void) dbuf_read(db, NULL, DB_RF_MUST_SUCCEED); 217 arc_release(db->db_buf, db); 218 bp = (blkptr_t *)db->db.db_data; 219 220 epbs = db->db_dnode->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 221 shift = (db->db_level - 1) * epbs; 222 dbstart = db->db_blkid << epbs; 223 start = blkid >> shift; 224 if (dbstart < start) { 225 bp += start - dbstart; 226 all = FALSE; 227 } else { 228 start = dbstart; 229 } 230 dbend = ((db->db_blkid + 1) << epbs) - 1; 231 end = (blkid + nblks - 1) >> shift; 232 if (dbend <= end) 233 end = dbend; 234 else if (all) 235 all = trunc; 236 ASSERT3U(start, <=, end); 237 238 if (db->db_level == 1) { 239 FREE_VERIFY(db, start, end, tx); 240 free_blocks(dn, bp, end-start+1, tx); 241 arc_buf_freeze(db->db_buf); 242 ASSERT(all || list_link_active(&db->db_dirty_node[txgoff])); 243 return (all); 244 } 245 246 for (i = start; i <= end; i++, bp++) { 247 if (BP_IS_HOLE(bp)) 248 continue; 249 rw_enter(&dn->dn_struct_rwlock, RW_READER); 250 err = dbuf_hold_impl(dn, db->db_level-1, i, TRUE, FTAG, &subdb); 251 ASSERT3U(err, ==, 0); 252 rw_exit(&dn->dn_struct_rwlock); 253 254 if (free_children(subdb, blkid, nblks, trunc, tx)) { 255 ASSERT3P(subdb->db_blkptr, ==, bp); 256 free_blocks(dn, bp, 1, tx); 257 } else { 258 all = FALSE; 259 } 260 dbuf_rele(subdb, FTAG); 261 } 262 arc_buf_freeze(db->db_buf); 263 #ifdef ZFS_DEBUG 264 bp -= (end-start)+1; 265 for (i = start; i <= end; i++, bp++) { 266 if (i == start && blkid != 0) 267 continue; 268 else if (i == end && !trunc) 269 continue; 270 ASSERT3U(bp->blk_birth, ==, 0); 271 } 272 #endif 273 ASSERT(all || list_link_active(&db->db_dirty_node[txgoff])); 274 return (all); 275 } 276 277 /* 278 * free_range: Traverse the indicated range of the provided file 279 * and "free" all the blocks contained there. 280 */ 281 static void 282 dnode_sync_free_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 283 { 284 blkptr_t *bp = dn->dn_phys->dn_blkptr; 285 dmu_buf_impl_t *db; 286 int trunc, start, end, shift, i, err; 287 int dnlevel = dn->dn_phys->dn_nlevels; 288 289 if (blkid > dn->dn_phys->dn_maxblkid) 290 return; 291 292 ASSERT(dn->dn_phys->dn_maxblkid < UINT64_MAX); 293 trunc = blkid + nblks > dn->dn_phys->dn_maxblkid; 294 if (trunc) 295 nblks = dn->dn_phys->dn_maxblkid - blkid + 1; 296 297 /* There are no indirect blocks in the object */ 298 if (dnlevel == 1) { 299 if (blkid >= dn->dn_phys->dn_nblkptr) { 300 /* this range was never made persistent */ 301 return; 302 } 303 ASSERT3U(blkid + nblks, <=, dn->dn_phys->dn_nblkptr); 304 free_blocks(dn, bp + blkid, nblks, tx); 305 if (trunc) { 306 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 307 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 308 dn->dn_phys->dn_maxblkid = (blkid ? blkid - 1 : 0); 309 ASSERT(off < dn->dn_phys->dn_maxblkid || 310 dn->dn_phys->dn_maxblkid == 0 || 311 dnode_next_offset(dn, FALSE, &off, 312 1, 1, 0) != 0); 313 } 314 return; 315 } 316 317 shift = (dnlevel - 1) * (dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT); 318 start = blkid >> shift; 319 ASSERT(start < dn->dn_phys->dn_nblkptr); 320 end = (blkid + nblks - 1) >> shift; 321 bp += start; 322 for (i = start; i <= end; i++, bp++) { 323 if (BP_IS_HOLE(bp)) 324 continue; 325 rw_enter(&dn->dn_struct_rwlock, RW_READER); 326 err = dbuf_hold_impl(dn, dnlevel-1, i, TRUE, FTAG, &db); 327 ASSERT3U(err, ==, 0); 328 rw_exit(&dn->dn_struct_rwlock); 329 330 if (free_children(db, blkid, nblks, trunc, tx)) { 331 ASSERT3P(db->db_blkptr, ==, bp); 332 free_blocks(dn, bp, 1, tx); 333 } 334 dbuf_rele(db, FTAG); 335 } 336 if (trunc) { 337 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 338 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 339 dn->dn_phys->dn_maxblkid = (blkid ? blkid - 1 : 0); 340 ASSERT(off < dn->dn_phys->dn_maxblkid || 341 dn->dn_phys->dn_maxblkid == 0 || 342 dnode_next_offset(dn, FALSE, &off, 1, 1, 0) != 0); 343 } 344 } 345 346 /* 347 * Try to kick all the dnodes dbufs out of the cache... 348 */ 349 int 350 dnode_evict_dbufs(dnode_t *dn, int try) 351 { 352 int progress; 353 int pass = 0; 354 355 do { 356 dmu_buf_impl_t *db, marker; 357 int evicting = FALSE; 358 359 progress = FALSE; 360 mutex_enter(&dn->dn_dbufs_mtx); 361 list_insert_tail(&dn->dn_dbufs, &marker); 362 db = list_head(&dn->dn_dbufs); 363 for (; db != ▮ db = list_head(&dn->dn_dbufs)) { 364 list_remove(&dn->dn_dbufs, db); 365 list_insert_tail(&dn->dn_dbufs, db); 366 367 mutex_enter(&db->db_mtx); 368 if (db->db_state == DB_EVICTING) { 369 progress = TRUE; 370 evicting = TRUE; 371 mutex_exit(&db->db_mtx); 372 } else if (refcount_is_zero(&db->db_holds)) { 373 progress = TRUE; 374 ASSERT(!arc_released(db->db_buf)); 375 dbuf_clear(db); /* exits db_mtx for us */ 376 } else { 377 mutex_exit(&db->db_mtx); 378 } 379 380 } 381 list_remove(&dn->dn_dbufs, &marker); 382 /* 383 * NB: we need to drop dn_dbufs_mtx between passes so 384 * that any DB_EVICTING dbufs can make progress. 385 * Ideally, we would have some cv we could wait on, but 386 * since we don't, just wait a bit to give the other 387 * thread a chance to run. 388 */ 389 mutex_exit(&dn->dn_dbufs_mtx); 390 if (evicting) 391 delay(1); 392 pass++; 393 ASSERT(pass < 100); /* sanity check */ 394 } while (progress); 395 396 /* 397 * This function works fine even if it can't evict everything. 398 * If were only asked to try to evict everything then 399 * return an error if we can't. Otherwise panic as the caller 400 * expects total eviction. 401 */ 402 if (list_head(&dn->dn_dbufs) != NULL) { 403 if (try) { 404 return (1); 405 } else { 406 panic("dangling dbufs (dn=%p, dbuf=%p)\n", 407 dn, list_head(&dn->dn_dbufs)); 408 } 409 } 410 411 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 412 if (dn->dn_bonus && refcount_is_zero(&dn->dn_bonus->db_holds)) { 413 mutex_enter(&dn->dn_bonus->db_mtx); 414 dbuf_evict(dn->dn_bonus); 415 dn->dn_bonus = NULL; 416 } 417 rw_exit(&dn->dn_struct_rwlock); 418 return (0); 419 } 420 421 static int 422 dnode_sync_free(dnode_t *dn, dmu_tx_t *tx) 423 { 424 dmu_buf_impl_t *db; 425 int txgoff = tx->tx_txg & TXG_MASK; 426 427 ASSERT(dmu_tx_is_syncing(tx)); 428 429 /* Undirty all buffers */ 430 while (db = list_head(&dn->dn_dirty_dbufs[txgoff])) { 431 mutex_enter(&db->db_mtx); 432 /* XXX - use dbuf_undirty()? */ 433 list_remove(&dn->dn_dirty_dbufs[txgoff], db); 434 if (db->db_level == 0) { 435 ASSERT(db->db_blkid == DB_BONUS_BLKID || 436 db->db_d.db_data_old[txgoff] == db->db_buf); 437 if (db->db_d.db_overridden_by[txgoff]) 438 dbuf_unoverride(db, tx->tx_txg); 439 db->db_d.db_data_old[txgoff] = NULL; 440 } 441 db->db_dirtycnt -= 1; 442 mutex_exit(&db->db_mtx); 443 dbuf_rele(db, (void *)(uintptr_t)tx->tx_txg); 444 } 445 446 (void) dnode_evict_dbufs(dn, 0); 447 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 448 449 /* 450 * XXX - It would be nice to assert this, but we may still 451 * have residual holds from async evictions from the arc... 452 * 453 * zfs_obj_to_path() also depends on this being 454 * commented out. 455 * 456 * ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); 457 */ 458 459 /* Undirty next bits */ 460 dn->dn_next_nlevels[txgoff] = 0; 461 dn->dn_next_indblkshift[txgoff] = 0; 462 dn->dn_next_blksz[txgoff] = 0; 463 464 /* free up all the blocks in the file. */ 465 dnode_sync_free_range(dn, 0, dn->dn_phys->dn_maxblkid+1, tx); 466 ASSERT3U(DN_USED_BYTES(dn->dn_phys), ==, 0); 467 468 /* ASSERT(blkptrs are zero); */ 469 ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE); 470 ASSERT(dn->dn_type != DMU_OT_NONE); 471 472 ASSERT(dn->dn_free_txg > 0); 473 if (dn->dn_allocated_txg != dn->dn_free_txg) 474 dbuf_will_dirty(dn->dn_dbuf, tx); 475 bzero(dn->dn_phys, sizeof (dnode_phys_t)); 476 477 mutex_enter(&dn->dn_mtx); 478 dn->dn_type = DMU_OT_NONE; 479 dn->dn_maxblkid = 0; 480 dn->dn_allocated_txg = 0; 481 mutex_exit(&dn->dn_mtx); 482 483 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT); 484 485 dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg); 486 /* 487 * Now that we've released our hold, the dnode may 488 * be evicted, so we musn't access it. 489 */ 490 return (1); 491 } 492 493 /* 494 * Write out the dnode's dirty buffers at the specified level. 495 * This may create more dirty buffers at the next level up. 496 * 497 * NOTE: The dnode is kept in memory by being dirty. Once the 498 * dirty bit is cleared, it may be evicted. Beware of this! 499 */ 500 int 501 dnode_sync(dnode_t *dn, int level, zio_t *zio, dmu_tx_t *tx) 502 { 503 free_range_t *rp; 504 int txgoff = tx->tx_txg & TXG_MASK; 505 dnode_phys_t *dnp = dn->dn_phys; 506 507 ASSERT(dmu_tx_is_syncing(tx)); 508 ASSERT(dnp->dn_type != DMU_OT_NONE || dn->dn_allocated_txg); 509 DNODE_VERIFY(dn); 510 511 /* 512 * Make sure the dbuf for the dn_phys is released before we modify it. 513 */ 514 if (dn->dn_dbuf) 515 arc_release(dn->dn_dbuf->db_buf, dn->dn_dbuf); 516 517 mutex_enter(&dn->dn_mtx); 518 if (dn->dn_allocated_txg == tx->tx_txg) { 519 /* The dnode is newly allocated or reallocated */ 520 if (dnp->dn_type == DMU_OT_NONE) { 521 /* this is a first alloc, not a realloc */ 522 /* XXX shouldn't the phys already be zeroed? */ 523 bzero(dnp, DNODE_CORE_SIZE); 524 dnp->dn_nlevels = 1; 525 } 526 527 if (dn->dn_nblkptr > dnp->dn_nblkptr) { 528 /* zero the new blkptrs we are gaining */ 529 bzero(dnp->dn_blkptr + dnp->dn_nblkptr, 530 sizeof (blkptr_t) * 531 (dn->dn_nblkptr - dnp->dn_nblkptr)); 532 } 533 dnp->dn_type = dn->dn_type; 534 dnp->dn_bonustype = dn->dn_bonustype; 535 dnp->dn_bonuslen = dn->dn_bonuslen; 536 dnp->dn_nblkptr = dn->dn_nblkptr; 537 } 538 539 ASSERT(level != 0 || dnp->dn_nlevels > 1 || 540 BP_IS_HOLE(&dnp->dn_blkptr[0]) || 541 BP_GET_LSIZE(&dnp->dn_blkptr[0]) == 542 dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 543 544 if (dn->dn_next_blksz[txgoff]) { 545 ASSERT(P2PHASE(dn->dn_next_blksz[txgoff], 546 SPA_MINBLOCKSIZE) == 0); 547 ASSERT(BP_IS_HOLE(&dnp->dn_blkptr[0]) || 548 list_head(&dn->dn_dirty_dbufs[txgoff]) != NULL || 549 dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT == 550 dnp->dn_datablkszsec); 551 dnp->dn_datablkszsec = 552 dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT; 553 dn->dn_next_blksz[txgoff] = 0; 554 } 555 556 if (dn->dn_next_indblkshift[txgoff]) { 557 ASSERT(dnp->dn_nlevels == 1); 558 dnp->dn_indblkshift = dn->dn_next_indblkshift[txgoff]; 559 dn->dn_next_indblkshift[txgoff] = 0; 560 } 561 562 /* 563 * Just take the live (open-context) values for checksum and compress. 564 * Strictly speaking it's a future leak, but nothing bad happens if we 565 * start using the new checksum or compress algorithm a little early. 566 */ 567 dnp->dn_checksum = dn->dn_checksum; 568 dnp->dn_compress = dn->dn_compress; 569 570 mutex_exit(&dn->dn_mtx); 571 572 /* process all the "freed" ranges in the file */ 573 if (dn->dn_free_txg == 0 || dn->dn_free_txg > tx->tx_txg) { 574 for (rp = avl_last(&dn->dn_ranges[txgoff]); rp != NULL; 575 rp = AVL_PREV(&dn->dn_ranges[txgoff], rp)) 576 dnode_sync_free_range(dn, 577 rp->fr_blkid, rp->fr_nblks, tx); 578 } 579 mutex_enter(&dn->dn_mtx); 580 for (rp = avl_first(&dn->dn_ranges[txgoff]); rp; ) { 581 free_range_t *last = rp; 582 rp = AVL_NEXT(&dn->dn_ranges[txgoff], rp); 583 avl_remove(&dn->dn_ranges[txgoff], last); 584 kmem_free(last, sizeof (free_range_t)); 585 } 586 mutex_exit(&dn->dn_mtx); 587 588 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= tx->tx_txg) { 589 ASSERT3U(level, ==, 0); 590 return (dnode_sync_free(dn, tx)); 591 } 592 593 if (dn->dn_next_nlevels[txgoff]) { 594 int new_lvl = dn->dn_next_nlevels[txgoff]; 595 596 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 597 while (new_lvl > dnp->dn_nlevels) 598 dnode_increase_indirection(dn, tx); 599 rw_exit(&dn->dn_struct_rwlock); 600 dn->dn_next_nlevels[txgoff] = 0; 601 } 602 603 if (level == dnp->dn_nlevels) { 604 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 605 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 606 607 /* we've already synced out all data and indirect blocks */ 608 /* there are no more dirty dbufs under this dnode */ 609 ASSERT3P(list_head(&dn->dn_dirty_dbufs[txgoff]), ==, NULL); 610 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= tx->tx_txg); 611 612 /* NB: the "off < maxblkid" is to catch overflow */ 613 /* 614 * NB: if blocksize is changing, we could get confused, 615 * so only bother if there are multiple blocks and thus 616 * it can't be changing. 617 */ 618 ASSERT(off < dn->dn_phys->dn_maxblkid || 619 dn->dn_phys->dn_maxblkid == 0 || 620 dnode_next_offset(dn, FALSE, &off, 1, 1, 0) != 0); 621 622 ASSERT(dnp->dn_nlevels > 1 || 623 BP_IS_HOLE(&dnp->dn_blkptr[0]) || 624 BP_GET_LSIZE(&dnp->dn_blkptr[0]) == 625 dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 626 627 if (dn->dn_object != DMU_META_DNODE_OBJECT) { 628 dbuf_will_dirty(dn->dn_dbuf, tx); 629 dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg); 630 } 631 632 /* 633 * Now that we've dropped the reference, the dnode may 634 * be evicted, so we musn't access it. 635 */ 636 return (1); 637 } else { 638 dmu_buf_impl_t *db, *db_next; 639 list_t *list = &dn->dn_dirty_dbufs[txgoff]; 640 /* 641 * Iterate over the list, removing and sync'ing dbufs 642 * which are on the level we want, and leaving others. 643 */ 644 for (db = list_head(list); db; db = db_next) { 645 db_next = list_next(list, db); 646 if (db->db_level == level) { 647 list_remove(list, db); 648 dbuf_sync(db, zio, tx); 649 } 650 } 651 return (0); 652 } 653 } 654