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 2006 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 } 66 67 dn->dn_phys->dn_nlevels += 1; 68 dprintf("os=%p obj=%llu, increase to %d\n", 69 dn->dn_objset, dn->dn_object, 70 dn->dn_phys->dn_nlevels); 71 72 /* set dbuf's parent pointers to new indirect buf */ 73 for (i = 0; i < dn->dn_phys->dn_nblkptr; i++) { 74 dmu_buf_impl_t *child = 75 dbuf_find(dn, dn->dn_phys->dn_nlevels-2, i); 76 if (child == NULL) 77 continue; 78 if (child->db_dnode == NULL) { 79 mutex_exit(&child->db_mtx); 80 continue; 81 } 82 83 if (child->db_parent == NULL || 84 child->db_parent == dn->dn_dbuf) { 85 dprintf_dbuf_bp(child, child->db_blkptr, 86 "changing db_blkptr to new indirect %s", ""); 87 child->db_parent = db; 88 dbuf_add_ref(db, child); 89 if (db->db.db_data) { 90 child->db_blkptr = 91 (blkptr_t *)db->db.db_data + i; 92 } else { 93 child->db_blkptr = NULL; 94 } 95 dprintf_dbuf_bp(child, child->db_blkptr, 96 "changed db_blkptr to new indirect %s", ""); 97 } 98 ASSERT3P(child->db_parent, ==, db); 99 100 mutex_exit(&child->db_mtx); 101 } 102 103 bzero(dn->dn_phys->dn_blkptr, 104 sizeof (blkptr_t) * dn->dn_phys->dn_nblkptr); 105 106 dbuf_rele(db, FTAG); 107 } 108 109 static void 110 free_blocks(dnode_t *dn, blkptr_t *bp, int num, dmu_tx_t *tx) 111 { 112 objset_impl_t *os = dn->dn_objset; 113 uint64_t bytesfreed = 0; 114 int i; 115 116 dprintf("os=%p obj=%llx num=%d\n", os, dn->dn_object, num); 117 118 for (i = 0; i < num; i++, bp++) { 119 if (BP_IS_HOLE(bp)) 120 continue; 121 122 bytesfreed += BP_GET_ASIZE(bp); 123 ASSERT3U(bytesfreed >> DEV_BSHIFT, <=, dn->dn_phys->dn_secphys); 124 dsl_dataset_block_kill(os->os_dsl_dataset, bp, tx); 125 } 126 dnode_diduse_space(dn, -bytesfreed); 127 } 128 129 #ifdef ZFS_DEBUG 130 static void 131 free_verify(dmu_buf_impl_t *db, uint64_t start, uint64_t end, dmu_tx_t *tx) 132 { 133 int off, num; 134 int i, err, epbs; 135 uint64_t txg = tx->tx_txg; 136 137 epbs = db->db_dnode->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 138 off = start - (db->db_blkid * 1<<epbs); 139 num = end - start + 1; 140 141 ASSERT3U(off, >=, 0); 142 ASSERT3U(num, >=, 0); 143 ASSERT3U(db->db_level, >, 0); 144 ASSERT3U(db->db.db_size, ==, 1<<db->db_dnode->dn_phys->dn_indblkshift); 145 ASSERT3U(off+num, <=, db->db.db_size >> SPA_BLKPTRSHIFT); 146 ASSERT(db->db_blkptr != NULL); 147 148 for (i = off; i < off+num; i++) { 149 uint64_t *buf; 150 int j; 151 dmu_buf_impl_t *child; 152 153 ASSERT(db->db_level == 1); 154 155 rw_enter(&db->db_dnode->dn_struct_rwlock, RW_READER); 156 err = dbuf_hold_impl(db->db_dnode, db->db_level-1, 157 (db->db_blkid << epbs) + i, TRUE, FTAG, &child); 158 rw_exit(&db->db_dnode->dn_struct_rwlock); 159 if (err == ENOENT) 160 continue; 161 ASSERT(err == 0); 162 ASSERT(child->db_level == 0); 163 ASSERT(!list_link_active(&child->db_dirty_node[txg&TXG_MASK])); 164 165 /* db_data_old better be zeroed */ 166 if (child->db_d.db_data_old[txg & TXG_MASK]) { 167 buf = ((arc_buf_t *)child->db_d.db_data_old 168 [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 ASSERT(all || list_link_active(&db->db_dirty_node[txgoff])); 242 return (all); 243 } 244 245 for (i = start; i <= end; i++, bp++) { 246 if (BP_IS_HOLE(bp)) 247 continue; 248 rw_enter(&dn->dn_struct_rwlock, RW_READER); 249 err = dbuf_hold_impl(dn, db->db_level-1, i, TRUE, FTAG, &subdb); 250 ASSERT3U(err, ==, 0); 251 rw_exit(&dn->dn_struct_rwlock); 252 253 if (free_children(subdb, blkid, nblks, trunc, tx)) { 254 ASSERT3P(subdb->db_blkptr, ==, bp); 255 free_blocks(dn, bp, 1, tx); 256 } else { 257 all = FALSE; 258 } 259 dbuf_rele(subdb, FTAG); 260 } 261 #ifdef ZFS_DEBUG 262 bp -= (end-start)+1; 263 for (i = start; i <= end; i++, bp++) { 264 if (i == start && blkid != 0) 265 continue; 266 else if (i == end && !trunc) 267 continue; 268 ASSERT3U(bp->blk_birth, ==, 0); 269 } 270 #endif 271 ASSERT(all || list_link_active(&db->db_dirty_node[txgoff])); 272 return (all); 273 } 274 275 /* 276 * free_range: Traverse the indicated range of the provided file 277 * and "free" all the blocks contained there. 278 */ 279 static void 280 dnode_sync_free_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 281 { 282 blkptr_t *bp = dn->dn_phys->dn_blkptr; 283 dmu_buf_impl_t *db; 284 int trunc, start, end, shift, i, err; 285 int dnlevel = dn->dn_phys->dn_nlevels; 286 287 if (blkid > dn->dn_phys->dn_maxblkid) 288 return; 289 290 ASSERT(dn->dn_phys->dn_maxblkid < UINT64_MAX); 291 trunc = blkid + nblks > dn->dn_phys->dn_maxblkid; 292 if (trunc) 293 nblks = dn->dn_phys->dn_maxblkid - blkid + 1; 294 295 /* There are no indirect blocks in the object */ 296 if (dnlevel == 1) { 297 if (blkid >= dn->dn_phys->dn_nblkptr) { 298 /* this range was never made persistent */ 299 return; 300 } 301 ASSERT3U(blkid + nblks, <=, dn->dn_phys->dn_nblkptr); 302 free_blocks(dn, bp + blkid, nblks, tx); 303 if (trunc) { 304 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 305 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 306 dn->dn_phys->dn_maxblkid = (blkid ? blkid - 1 : 0); 307 ASSERT(off < dn->dn_phys->dn_maxblkid || 308 dn->dn_phys->dn_maxblkid == 0 || 309 dnode_next_offset(dn, FALSE, &off, 1, 1) == ESRCH); 310 } 311 return; 312 } 313 314 shift = (dnlevel - 1) * (dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT); 315 start = blkid >> shift; 316 ASSERT(start < dn->dn_phys->dn_nblkptr); 317 end = (blkid + nblks - 1) >> shift; 318 bp += start; 319 for (i = start; i <= end; i++, bp++) { 320 if (BP_IS_HOLE(bp)) 321 continue; 322 rw_enter(&dn->dn_struct_rwlock, RW_READER); 323 err = dbuf_hold_impl(dn, dnlevel-1, i, TRUE, FTAG, &db); 324 ASSERT3U(err, ==, 0); 325 rw_exit(&dn->dn_struct_rwlock); 326 327 if (free_children(db, blkid, nblks, trunc, tx)) { 328 ASSERT3P(db->db_blkptr, ==, bp); 329 free_blocks(dn, bp, 1, tx); 330 } 331 dbuf_rele(db, FTAG); 332 } 333 if (trunc) { 334 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 335 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 336 dn->dn_phys->dn_maxblkid = (blkid ? blkid - 1 : 0); 337 ASSERT(off < dn->dn_phys->dn_maxblkid || 338 dn->dn_phys->dn_maxblkid == 0 || 339 dnode_next_offset(dn, FALSE, &off, 1, 1) == ESRCH); 340 } 341 } 342 343 /* 344 * Try to kick all the dnodes dbufs out of the cache... 345 */ 346 void 347 dnode_evict_dbufs(dnode_t *dn) 348 { 349 int progress; 350 int pass = 0; 351 352 do { 353 dmu_buf_impl_t *db, *db_next; 354 int evicting = FALSE; 355 356 progress = FALSE; 357 mutex_enter(&dn->dn_dbufs_mtx); 358 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 359 /* dbuf_clear() may remove db from this list */ 360 db_next = list_next(&dn->dn_dbufs, db); 361 362 mutex_enter(&db->db_mtx); 363 if (db->db_state == DB_EVICTING) { 364 progress = TRUE; 365 evicting = TRUE; 366 mutex_exit(&db->db_mtx); 367 } else if (refcount_is_zero(&db->db_holds)) { 368 progress = TRUE; 369 ASSERT(!arc_released(db->db_buf)); 370 dbuf_clear(db); /* exits db_mtx for us */ 371 } else { 372 mutex_exit(&db->db_mtx); 373 } 374 375 } 376 /* 377 * NB: we need to drop dn_dbufs_mtx between passes so 378 * that any DB_EVICTING dbufs can make progress. 379 * Ideally, we would have some cv we could wait on, but 380 * since we don't, just wait a bit to give the other 381 * thread a chance to run. 382 */ 383 mutex_exit(&dn->dn_dbufs_mtx); 384 if (evicting) 385 delay(1); 386 pass++; 387 ASSERT(pass < 100); /* sanity check */ 388 } while (progress); 389 390 /* 391 * This function works fine even if it can't evict everything, 392 * but all of our callers need this assertion, so let's put it 393 * here (for now). Perhaps in the future there will be a try vs 394 * doall flag. 395 */ 396 if (list_head(&dn->dn_dbufs) != NULL) { 397 panic("dangling dbufs (dn=%p, dbuf=%p)\n", 398 dn, list_head(&dn->dn_dbufs)); 399 } 400 401 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 402 if (dn->dn_bonus && refcount_is_zero(&dn->dn_bonus->db_holds)) { 403 mutex_enter(&dn->dn_bonus->db_mtx); 404 dbuf_evict(dn->dn_bonus); 405 dn->dn_bonus = NULL; 406 } 407 rw_exit(&dn->dn_struct_rwlock); 408 409 } 410 411 static int 412 dnode_sync_free(dnode_t *dn, dmu_tx_t *tx) 413 { 414 dmu_buf_impl_t *db; 415 int txgoff = tx->tx_txg & TXG_MASK; 416 417 ASSERT(dmu_tx_is_syncing(tx)); 418 419 /* Undirty all buffers */ 420 while (db = list_head(&dn->dn_dirty_dbufs[txgoff])) { 421 mutex_enter(&db->db_mtx); 422 /* XXX - use dbuf_undirty()? */ 423 list_remove(&dn->dn_dirty_dbufs[txgoff], db); 424 if (db->db_level == 0) { 425 ASSERT(db->db_blkid == DB_BONUS_BLKID || 426 db->db_d.db_data_old[txgoff] == db->db_buf); 427 if (db->db_d.db_overridden_by[txgoff]) 428 dbuf_unoverride(db, tx->tx_txg); 429 db->db_d.db_data_old[txgoff] = NULL; 430 } 431 db->db_dirtycnt -= 1; 432 mutex_exit(&db->db_mtx); 433 dbuf_rele(db, (void *)(uintptr_t)tx->tx_txg); 434 } 435 436 dnode_evict_dbufs(dn); 437 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 438 439 /* 440 * XXX - It would be nice to assert this, but we may still 441 * have residual holds from async evictions from the arc... 442 * 443 * ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); 444 */ 445 446 /* Undirty next bits */ 447 dn->dn_next_nlevels[txgoff] = 0; 448 dn->dn_next_indblkshift[txgoff] = 0; 449 dn->dn_next_blksz[txgoff] = 0; 450 451 /* free up all the blocks in the file. */ 452 dnode_sync_free_range(dn, 0, dn->dn_phys->dn_maxblkid+1, tx); 453 ASSERT3U(dn->dn_phys->dn_secphys, ==, 0); 454 455 /* ASSERT(blkptrs are zero); */ 456 ASSERT(dn->dn_phys->dn_type != DMU_OT_NONE); 457 ASSERT(dn->dn_type != DMU_OT_NONE); 458 459 ASSERT(dn->dn_free_txg > 0); 460 if (dn->dn_allocated_txg != dn->dn_free_txg) 461 dbuf_will_dirty(dn->dn_dbuf, tx); 462 bzero(dn->dn_phys, sizeof (dnode_phys_t)); 463 464 mutex_enter(&dn->dn_mtx); 465 dn->dn_type = DMU_OT_NONE; 466 dn->dn_maxblkid = 0; 467 dn->dn_allocated_txg = 0; 468 mutex_exit(&dn->dn_mtx); 469 470 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT); 471 472 dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg); 473 /* 474 * Now that we've released our hold, the dnode may 475 * be evicted, so we musn't access it. 476 */ 477 return (1); 478 } 479 480 /* 481 * Write out the dnode's dirty buffers at the specified level. 482 * This may create more dirty buffers at the next level up. 483 * 484 * NOTE: The dnode is kept in memory by being dirty. Once the 485 * dirty bit is cleared, it may be evicted. Beware of this! 486 */ 487 int 488 dnode_sync(dnode_t *dn, int level, zio_t *zio, dmu_tx_t *tx) 489 { 490 free_range_t *rp; 491 int txgoff = tx->tx_txg & TXG_MASK; 492 dnode_phys_t *dnp = dn->dn_phys; 493 494 ASSERT(dmu_tx_is_syncing(tx)); 495 ASSERT(dnp->dn_type != DMU_OT_NONE || dn->dn_allocated_txg); 496 DNODE_VERIFY(dn); 497 498 /* 499 * Make sure the dbuf for the dn_phys is released before we modify it. 500 */ 501 if (dn->dn_dbuf) 502 arc_release(dn->dn_dbuf->db_buf, dn->dn_dbuf); 503 504 mutex_enter(&dn->dn_mtx); 505 if (dn->dn_allocated_txg == tx->tx_txg) { 506 /* The dnode is newly allocated or reallocated */ 507 if (dnp->dn_type == DMU_OT_NONE) { 508 /* this is a first alloc, not a realloc */ 509 /* XXX shouldn't the phys already be zeroed? */ 510 bzero(dnp, DNODE_CORE_SIZE); 511 dnp->dn_datablkszsec = dn->dn_datablkszsec; 512 dnp->dn_indblkshift = dn->dn_indblkshift; 513 dnp->dn_nlevels = 1; 514 } 515 516 if (dn->dn_nblkptr > dnp->dn_nblkptr) { 517 /* zero the new blkptrs we are gaining */ 518 bzero(dnp->dn_blkptr + dnp->dn_nblkptr, 519 sizeof (blkptr_t) * 520 (dn->dn_nblkptr - dnp->dn_nblkptr)); 521 } 522 dnp->dn_type = dn->dn_type; 523 dnp->dn_bonustype = dn->dn_bonustype; 524 dnp->dn_bonuslen = dn->dn_bonuslen; 525 dnp->dn_nblkptr = dn->dn_nblkptr; 526 } 527 528 if (dn->dn_next_blksz[txgoff]) { 529 ASSERT(P2PHASE(dn->dn_next_blksz[txgoff], 530 SPA_MINBLOCKSIZE) == 0); 531 dnp->dn_datablkszsec = 532 dn->dn_next_blksz[txgoff] >> SPA_MINBLOCKSHIFT; 533 dn->dn_next_blksz[txgoff] = 0; 534 } 535 536 if (dn->dn_next_indblkshift[txgoff]) { 537 ASSERT(dnp->dn_nlevels == 1); 538 dnp->dn_indblkshift = dn->dn_next_indblkshift[txgoff]; 539 dn->dn_next_indblkshift[txgoff] = 0; 540 } 541 542 /* 543 * Just take the live (open-context) values for checksum and compress. 544 * Strictly speaking it's a future leak, but nothing bad happens if we 545 * start using the new checksum or compress algorithm a little early. 546 */ 547 dnp->dn_checksum = dn->dn_checksum; 548 dnp->dn_compress = dn->dn_compress; 549 550 mutex_exit(&dn->dn_mtx); 551 552 /* process all the "freed" ranges in the file */ 553 if (dn->dn_free_txg == 0 || dn->dn_free_txg > tx->tx_txg) { 554 for (rp = avl_last(&dn->dn_ranges[txgoff]); rp != NULL; 555 rp = AVL_PREV(&dn->dn_ranges[txgoff], rp)) 556 dnode_sync_free_range(dn, 557 rp->fr_blkid, rp->fr_nblks, tx); 558 } 559 mutex_enter(&dn->dn_mtx); 560 for (rp = avl_first(&dn->dn_ranges[txgoff]); rp; ) { 561 free_range_t *last = rp; 562 rp = AVL_NEXT(&dn->dn_ranges[txgoff], rp); 563 avl_remove(&dn->dn_ranges[txgoff], last); 564 kmem_free(last, sizeof (free_range_t)); 565 } 566 mutex_exit(&dn->dn_mtx); 567 568 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= tx->tx_txg) { 569 ASSERT3U(level, ==, 0); 570 return (dnode_sync_free(dn, tx)); 571 } 572 573 if (dn->dn_next_nlevels[txgoff]) { 574 int new_lvl = dn->dn_next_nlevels[txgoff]; 575 576 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 577 while (new_lvl > dnp->dn_nlevels) 578 dnode_increase_indirection(dn, tx); 579 rw_exit(&dn->dn_struct_rwlock); 580 dn->dn_next_nlevels[txgoff] = 0; 581 } 582 583 if (level == dnp->dn_nlevels) { 584 uint64_t off = (dn->dn_phys->dn_maxblkid + 1) * 585 (dn->dn_phys->dn_datablkszsec << SPA_MINBLOCKSHIFT); 586 587 /* we've already synced out all data and indirect blocks */ 588 /* there are no more dirty dbufs under this dnode */ 589 ASSERT3P(list_head(&dn->dn_dirty_dbufs[txgoff]), ==, NULL); 590 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= tx->tx_txg); 591 592 /* XXX this is expensive. remove once 6343073 is closed. */ 593 /* NB: the "off < maxblkid" is to catch overflow */ 594 /* 595 * NB: if blocksize is changing, we could get confused, 596 * so only bother if there are multiple blocks and thus 597 * it can't be changing. 598 */ 599 if (!(off < dn->dn_phys->dn_maxblkid || 600 dn->dn_phys->dn_maxblkid == 0 || 601 dnode_next_offset(dn, FALSE, &off, 1, 1) == ESRCH)) 602 panic("data after EOF: off=%llu\n", (u_longlong_t)off); 603 604 if (dn->dn_object != DMU_META_DNODE_OBJECT) { 605 dbuf_will_dirty(dn->dn_dbuf, tx); 606 dnode_rele(dn, (void *)(uintptr_t)tx->tx_txg); 607 } 608 609 /* 610 * Now that we've dropped the reference, the dnode may 611 * be evicted, so we musn't access it. 612 */ 613 return (1); 614 } else { 615 dmu_buf_impl_t *db, *db_next; 616 list_t *list = &dn->dn_dirty_dbufs[txgoff]; 617 /* 618 * Iterate over the list, removing and sync'ing dbufs 619 * which are on the level we want, and leaving others. 620 */ 621 for (db = list_head(list); db; db = db_next) { 622 db_next = list_next(list, db); 623 if (db->db_level == level) { 624 list_remove(list, db); 625 dbuf_sync(db, zio, tx); 626 } 627 } 628 return (0); 629 } 630 } 631