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) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 24 * Copyright (c) 2012, 2017 by Delphix. All rights reserved. 25 * Copyright (c) 2014 Integros [integros.com] 26 */ 27 28 #include <sys/dmu.h> 29 #include <sys/dmu_impl.h> 30 #include <sys/dbuf.h> 31 #include <sys/dmu_tx.h> 32 #include <sys/dmu_objset.h> 33 #include <sys/dsl_dataset.h> 34 #include <sys/dsl_dir.h> 35 #include <sys/dsl_pool.h> 36 #include <sys/zap_impl.h> 37 #include <sys/spa.h> 38 #include <sys/sa.h> 39 #include <sys/sa_impl.h> 40 #include <sys/zfs_context.h> 41 #include <sys/varargs.h> 42 43 typedef void (*dmu_tx_hold_func_t)(dmu_tx_t *tx, struct dnode *dn, 44 uint64_t arg1, uint64_t arg2); 45 46 47 dmu_tx_t * 48 dmu_tx_create_dd(dsl_dir_t *dd) 49 { 50 dmu_tx_t *tx = kmem_zalloc(sizeof (dmu_tx_t), KM_SLEEP); 51 tx->tx_dir = dd; 52 if (dd != NULL) 53 tx->tx_pool = dd->dd_pool; 54 list_create(&tx->tx_holds, sizeof (dmu_tx_hold_t), 55 offsetof(dmu_tx_hold_t, txh_node)); 56 list_create(&tx->tx_callbacks, sizeof (dmu_tx_callback_t), 57 offsetof(dmu_tx_callback_t, dcb_node)); 58 tx->tx_start = gethrtime(); 59 return (tx); 60 } 61 62 dmu_tx_t * 63 dmu_tx_create(objset_t *os) 64 { 65 dmu_tx_t *tx = dmu_tx_create_dd(os->os_dsl_dataset->ds_dir); 66 tx->tx_objset = os; 67 return (tx); 68 } 69 70 dmu_tx_t * 71 dmu_tx_create_assigned(struct dsl_pool *dp, uint64_t txg) 72 { 73 dmu_tx_t *tx = dmu_tx_create_dd(NULL); 74 75 txg_verify(dp->dp_spa, txg); 76 tx->tx_pool = dp; 77 tx->tx_txg = txg; 78 tx->tx_anyobj = TRUE; 79 80 return (tx); 81 } 82 83 int 84 dmu_tx_is_syncing(dmu_tx_t *tx) 85 { 86 return (tx->tx_anyobj); 87 } 88 89 int 90 dmu_tx_private_ok(dmu_tx_t *tx) 91 { 92 return (tx->tx_anyobj); 93 } 94 95 static dmu_tx_hold_t * 96 dmu_tx_hold_dnode_impl(dmu_tx_t *tx, dnode_t *dn, enum dmu_tx_hold_type type, 97 uint64_t arg1, uint64_t arg2) 98 { 99 dmu_tx_hold_t *txh; 100 101 if (dn != NULL) { 102 (void) refcount_add(&dn->dn_holds, tx); 103 if (tx->tx_txg != 0) { 104 mutex_enter(&dn->dn_mtx); 105 /* 106 * dn->dn_assigned_txg == tx->tx_txg doesn't pose a 107 * problem, but there's no way for it to happen (for 108 * now, at least). 109 */ 110 ASSERT(dn->dn_assigned_txg == 0); 111 dn->dn_assigned_txg = tx->tx_txg; 112 (void) refcount_add(&dn->dn_tx_holds, tx); 113 mutex_exit(&dn->dn_mtx); 114 } 115 } 116 117 txh = kmem_zalloc(sizeof (dmu_tx_hold_t), KM_SLEEP); 118 txh->txh_tx = tx; 119 txh->txh_dnode = dn; 120 refcount_create(&txh->txh_space_towrite); 121 refcount_create(&txh->txh_memory_tohold); 122 txh->txh_type = type; 123 txh->txh_arg1 = arg1; 124 txh->txh_arg2 = arg2; 125 list_insert_tail(&tx->tx_holds, txh); 126 127 return (txh); 128 } 129 130 static dmu_tx_hold_t * 131 dmu_tx_hold_object_impl(dmu_tx_t *tx, objset_t *os, uint64_t object, 132 enum dmu_tx_hold_type type, uint64_t arg1, uint64_t arg2) 133 { 134 dnode_t *dn = NULL; 135 dmu_tx_hold_t *txh; 136 int err; 137 138 if (object != DMU_NEW_OBJECT) { 139 err = dnode_hold(os, object, FTAG, &dn); 140 if (err != 0) { 141 tx->tx_err = err; 142 return (NULL); 143 } 144 } 145 txh = dmu_tx_hold_dnode_impl(tx, dn, type, arg1, arg2); 146 if (dn != NULL) 147 dnode_rele(dn, FTAG); 148 return (txh); 149 } 150 151 void 152 dmu_tx_add_new_object(dmu_tx_t *tx, dnode_t *dn) 153 { 154 /* 155 * If we're syncing, they can manipulate any object anyhow, and 156 * the hold on the dnode_t can cause problems. 157 */ 158 if (!dmu_tx_is_syncing(tx)) 159 (void) dmu_tx_hold_dnode_impl(tx, dn, THT_NEWOBJECT, 0, 0); 160 } 161 162 /* 163 * This function reads specified data from disk. The specified data will 164 * be needed to perform the transaction -- i.e, it will be read after 165 * we do dmu_tx_assign(). There are two reasons that we read the data now 166 * (before dmu_tx_assign()): 167 * 168 * 1. Reading it now has potentially better performance. The transaction 169 * has not yet been assigned, so the TXG is not held open, and also the 170 * caller typically has less locks held when calling dmu_tx_hold_*() than 171 * after the transaction has been assigned. This reduces the lock (and txg) 172 * hold times, thus reducing lock contention. 173 * 174 * 2. It is easier for callers (primarily the ZPL) to handle i/o errors 175 * that are detected before they start making changes to the DMU state 176 * (i.e. now). Once the transaction has been assigned, and some DMU 177 * state has been changed, it can be difficult to recover from an i/o 178 * error (e.g. to undo the changes already made in memory at the DMU 179 * layer). Typically code to do so does not exist in the caller -- it 180 * assumes that the data has already been cached and thus i/o errors are 181 * not possible. 182 * 183 * It has been observed that the i/o initiated here can be a performance 184 * problem, and it appears to be optional, because we don't look at the 185 * data which is read. However, removing this read would only serve to 186 * move the work elsewhere (after the dmu_tx_assign()), where it may 187 * have a greater impact on performance (in addition to the impact on 188 * fault tolerance noted above). 189 */ 190 static int 191 dmu_tx_check_ioerr(zio_t *zio, dnode_t *dn, int level, uint64_t blkid) 192 { 193 int err; 194 dmu_buf_impl_t *db; 195 196 rw_enter(&dn->dn_struct_rwlock, RW_READER); 197 db = dbuf_hold_level(dn, level, blkid, FTAG); 198 rw_exit(&dn->dn_struct_rwlock); 199 if (db == NULL) 200 return (SET_ERROR(EIO)); 201 err = dbuf_read(db, zio, DB_RF_CANFAIL | DB_RF_NOPREFETCH); 202 dbuf_rele(db, FTAG); 203 return (err); 204 } 205 206 /* ARGSUSED */ 207 static void 208 dmu_tx_count_write(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 209 { 210 dnode_t *dn = txh->txh_dnode; 211 int err = 0; 212 213 if (len == 0) 214 return; 215 216 (void) refcount_add_many(&txh->txh_space_towrite, len, FTAG); 217 218 if (refcount_count(&txh->txh_space_towrite) > 2 * DMU_MAX_ACCESS) 219 err = SET_ERROR(EFBIG); 220 221 if (dn == NULL) 222 return; 223 224 /* 225 * For i/o error checking, read the blocks that will be needed 226 * to perform the write: the first and last level-0 blocks (if 227 * they are not aligned, i.e. if they are partial-block writes), 228 * and all the level-1 blocks. 229 */ 230 if (dn->dn_maxblkid == 0) { 231 if (off < dn->dn_datablksz && 232 (off > 0 || len < dn->dn_datablksz)) { 233 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 234 if (err != 0) { 235 txh->txh_tx->tx_err = err; 236 } 237 } 238 } else { 239 zio_t *zio = zio_root(dn->dn_objset->os_spa, 240 NULL, NULL, ZIO_FLAG_CANFAIL); 241 242 /* first level-0 block */ 243 uint64_t start = off >> dn->dn_datablkshift; 244 if (P2PHASE(off, dn->dn_datablksz) || len < dn->dn_datablksz) { 245 err = dmu_tx_check_ioerr(zio, dn, 0, start); 246 if (err != 0) { 247 txh->txh_tx->tx_err = err; 248 } 249 } 250 251 /* last level-0 block */ 252 uint64_t end = (off + len - 1) >> dn->dn_datablkshift; 253 if (end != start && end <= dn->dn_maxblkid && 254 P2PHASE(off + len, dn->dn_datablksz)) { 255 err = dmu_tx_check_ioerr(zio, dn, 0, end); 256 if (err != 0) { 257 txh->txh_tx->tx_err = err; 258 } 259 } 260 261 /* level-1 blocks */ 262 if (dn->dn_nlevels > 1) { 263 int shft = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 264 for (uint64_t i = (start >> shft) + 1; 265 i < end >> shft; i++) { 266 err = dmu_tx_check_ioerr(zio, dn, 1, i); 267 if (err != 0) { 268 txh->txh_tx->tx_err = err; 269 } 270 } 271 } 272 273 err = zio_wait(zio); 274 if (err != 0) { 275 txh->txh_tx->tx_err = err; 276 } 277 } 278 } 279 280 static void 281 dmu_tx_count_dnode(dmu_tx_hold_t *txh) 282 { 283 (void) refcount_add_many(&txh->txh_space_towrite, DNODE_SIZE, FTAG); 284 } 285 286 void 287 dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len) 288 { 289 dmu_tx_hold_t *txh; 290 291 ASSERT0(tx->tx_txg); 292 ASSERT3U(len, <=, DMU_MAX_ACCESS); 293 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 294 295 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 296 object, THT_WRITE, off, len); 297 if (txh != NULL) { 298 dmu_tx_count_write(txh, off, len); 299 dmu_tx_count_dnode(txh); 300 } 301 } 302 303 void 304 dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len) 305 { 306 dmu_tx_hold_t *txh; 307 308 ASSERT0(tx->tx_txg); 309 ASSERT3U(len, <=, DMU_MAX_ACCESS); 310 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 311 312 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_WRITE, off, len); 313 if (txh != NULL) { 314 dmu_tx_count_write(txh, off, len); 315 dmu_tx_count_dnode(txh); 316 } 317 } 318 319 /* 320 * This function marks the transaction as being a "net free". The end 321 * result is that refquotas will be disabled for this transaction, and 322 * this transaction will be able to use half of the pool space overhead 323 * (see dsl_pool_adjustedsize()). Therefore this function should only 324 * be called for transactions that we expect will not cause a net increase 325 * in the amount of space used (but it's OK if that is occasionally not true). 326 */ 327 void 328 dmu_tx_mark_netfree(dmu_tx_t *tx) 329 { 330 tx->tx_netfree = B_TRUE; 331 } 332 333 static void 334 dmu_tx_hold_free_impl(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 335 { 336 dmu_tx_t *tx; 337 dnode_t *dn; 338 int err; 339 340 tx = txh->txh_tx; 341 ASSERT(tx->tx_txg == 0); 342 343 dn = txh->txh_dnode; 344 dmu_tx_count_dnode(txh); 345 346 if (off >= (dn->dn_maxblkid + 1) * dn->dn_datablksz) 347 return; 348 if (len == DMU_OBJECT_END) 349 len = (dn->dn_maxblkid + 1) * dn->dn_datablksz - off; 350 351 /* 352 * For i/o error checking, we read the first and last level-0 353 * blocks if they are not aligned, and all the level-1 blocks. 354 * 355 * Note: dbuf_free_range() assumes that we have not instantiated 356 * any level-0 dbufs that will be completely freed. Therefore we must 357 * exercise care to not read or count the first and last blocks 358 * if they are blocksize-aligned. 359 */ 360 if (dn->dn_datablkshift == 0) { 361 if (off != 0 || len < dn->dn_datablksz) 362 dmu_tx_count_write(txh, 0, dn->dn_datablksz); 363 } else { 364 /* first block will be modified if it is not aligned */ 365 if (!IS_P2ALIGNED(off, 1 << dn->dn_datablkshift)) 366 dmu_tx_count_write(txh, off, 1); 367 /* last block will be modified if it is not aligned */ 368 if (!IS_P2ALIGNED(off + len, 1 << dn->dn_datablkshift)) 369 dmu_tx_count_write(txh, off + len, 1); 370 } 371 372 /* 373 * Check level-1 blocks. 374 */ 375 if (dn->dn_nlevels > 1) { 376 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 377 SPA_BLKPTRSHIFT; 378 uint64_t start = off >> shift; 379 uint64_t end = (off + len) >> shift; 380 381 ASSERT(dn->dn_indblkshift != 0); 382 383 /* 384 * dnode_reallocate() can result in an object with indirect 385 * blocks having an odd data block size. In this case, 386 * just check the single block. 387 */ 388 if (dn->dn_datablkshift == 0) 389 start = end = 0; 390 391 zio_t *zio = zio_root(tx->tx_pool->dp_spa, 392 NULL, NULL, ZIO_FLAG_CANFAIL); 393 for (uint64_t i = start; i <= end; i++) { 394 uint64_t ibyte = i << shift; 395 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0); 396 i = ibyte >> shift; 397 if (err == ESRCH || i > end) 398 break; 399 if (err != 0) { 400 tx->tx_err = err; 401 (void) zio_wait(zio); 402 return; 403 } 404 405 (void) refcount_add_many(&txh->txh_memory_tohold, 406 1 << dn->dn_indblkshift, FTAG); 407 408 err = dmu_tx_check_ioerr(zio, dn, 1, i); 409 if (err != 0) { 410 tx->tx_err = err; 411 (void) zio_wait(zio); 412 return; 413 } 414 } 415 err = zio_wait(zio); 416 if (err != 0) { 417 tx->tx_err = err; 418 return; 419 } 420 } 421 } 422 423 void 424 dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len) 425 { 426 dmu_tx_hold_t *txh; 427 428 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 429 object, THT_FREE, off, len); 430 if (txh != NULL) 431 (void) dmu_tx_hold_free_impl(txh, off, len); 432 } 433 434 void 435 dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, uint64_t len) 436 { 437 dmu_tx_hold_t *txh; 438 439 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_FREE, off, len); 440 if (txh != NULL) 441 (void) dmu_tx_hold_free_impl(txh, off, len); 442 } 443 444 static void 445 dmu_tx_hold_zap_impl(dmu_tx_hold_t *txh, const char *name) 446 { 447 dmu_tx_t *tx = txh->txh_tx; 448 dnode_t *dn; 449 int err; 450 451 ASSERT(tx->tx_txg == 0); 452 453 dn = txh->txh_dnode; 454 455 dmu_tx_count_dnode(txh); 456 457 /* 458 * Modifying a almost-full microzap is around the worst case (128KB) 459 * 460 * If it is a fat zap, the worst case would be 7*16KB=112KB: 461 * - 3 blocks overwritten: target leaf, ptrtbl block, header block 462 * - 4 new blocks written if adding: 463 * - 2 blocks for possibly split leaves, 464 * - 2 grown ptrtbl blocks 465 */ 466 (void) refcount_add_many(&txh->txh_space_towrite, 467 MZAP_MAX_BLKSZ, FTAG); 468 469 if (dn == NULL) 470 return; 471 472 ASSERT3P(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP); 473 474 if (dn->dn_maxblkid == 0 || name == NULL) { 475 /* 476 * This is a microzap (only one block), or we don't know 477 * the name. Check the first block for i/o errors. 478 */ 479 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 480 if (err != 0) { 481 tx->tx_err = err; 482 } 483 } else { 484 /* 485 * Access the name so that we'll check for i/o errors to 486 * the leaf blocks, etc. We ignore ENOENT, as this name 487 * may not yet exist. 488 */ 489 err = zap_lookup_by_dnode(dn, name, 8, 0, NULL); 490 if (err == EIO || err == ECKSUM || err == ENXIO) { 491 tx->tx_err = err; 492 } 493 } 494 } 495 496 void 497 dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name) 498 { 499 dmu_tx_hold_t *txh; 500 501 ASSERT0(tx->tx_txg); 502 503 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 504 object, THT_ZAP, add, (uintptr_t)name); 505 if (txh != NULL) 506 dmu_tx_hold_zap_impl(txh, name); 507 } 508 509 void 510 dmu_tx_hold_zap_by_dnode(dmu_tx_t *tx, dnode_t *dn, int add, const char *name) 511 { 512 dmu_tx_hold_t *txh; 513 514 ASSERT0(tx->tx_txg); 515 ASSERT(dn != NULL); 516 517 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_ZAP, add, (uintptr_t)name); 518 if (txh != NULL) 519 dmu_tx_hold_zap_impl(txh, name); 520 } 521 522 void 523 dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object) 524 { 525 dmu_tx_hold_t *txh; 526 527 ASSERT(tx->tx_txg == 0); 528 529 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 530 object, THT_BONUS, 0, 0); 531 if (txh) 532 dmu_tx_count_dnode(txh); 533 } 534 535 void 536 dmu_tx_hold_bonus_by_dnode(dmu_tx_t *tx, dnode_t *dn) 537 { 538 dmu_tx_hold_t *txh; 539 540 ASSERT0(tx->tx_txg); 541 542 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_BONUS, 0, 0); 543 if (txh) 544 dmu_tx_count_dnode(txh); 545 } 546 547 void 548 dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space) 549 { 550 dmu_tx_hold_t *txh; 551 ASSERT(tx->tx_txg == 0); 552 553 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 554 DMU_NEW_OBJECT, THT_SPACE, space, 0); 555 556 (void) refcount_add_many(&txh->txh_space_towrite, space, FTAG); 557 } 558 559 #ifdef ZFS_DEBUG 560 void 561 dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db) 562 { 563 boolean_t match_object = B_FALSE; 564 boolean_t match_offset = B_FALSE; 565 566 DB_DNODE_ENTER(db); 567 dnode_t *dn = DB_DNODE(db); 568 ASSERT(tx->tx_txg != 0); 569 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset); 570 ASSERT3U(dn->dn_object, ==, db->db.db_object); 571 572 if (tx->tx_anyobj) { 573 DB_DNODE_EXIT(db); 574 return; 575 } 576 577 /* XXX No checking on the meta dnode for now */ 578 if (db->db.db_object == DMU_META_DNODE_OBJECT) { 579 DB_DNODE_EXIT(db); 580 return; 581 } 582 583 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 584 txh = list_next(&tx->tx_holds, txh)) { 585 ASSERT(dn == NULL || dn->dn_assigned_txg == tx->tx_txg); 586 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT) 587 match_object = TRUE; 588 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) { 589 int datablkshift = dn->dn_datablkshift ? 590 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT; 591 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 592 int shift = datablkshift + epbs * db->db_level; 593 uint64_t beginblk = shift >= 64 ? 0 : 594 (txh->txh_arg1 >> shift); 595 uint64_t endblk = shift >= 64 ? 0 : 596 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift); 597 uint64_t blkid = db->db_blkid; 598 599 /* XXX txh_arg2 better not be zero... */ 600 601 dprintf("found txh type %x beginblk=%llx endblk=%llx\n", 602 txh->txh_type, beginblk, endblk); 603 604 switch (txh->txh_type) { 605 case THT_WRITE: 606 if (blkid >= beginblk && blkid <= endblk) 607 match_offset = TRUE; 608 /* 609 * We will let this hold work for the bonus 610 * or spill buffer so that we don't need to 611 * hold it when creating a new object. 612 */ 613 if (blkid == DMU_BONUS_BLKID || 614 blkid == DMU_SPILL_BLKID) 615 match_offset = TRUE; 616 /* 617 * They might have to increase nlevels, 618 * thus dirtying the new TLIBs. Or the 619 * might have to change the block size, 620 * thus dirying the new lvl=0 blk=0. 621 */ 622 if (blkid == 0) 623 match_offset = TRUE; 624 break; 625 case THT_FREE: 626 /* 627 * We will dirty all the level 1 blocks in 628 * the free range and perhaps the first and 629 * last level 0 block. 630 */ 631 if (blkid >= beginblk && (blkid <= endblk || 632 txh->txh_arg2 == DMU_OBJECT_END)) 633 match_offset = TRUE; 634 break; 635 case THT_SPILL: 636 if (blkid == DMU_SPILL_BLKID) 637 match_offset = TRUE; 638 break; 639 case THT_BONUS: 640 if (blkid == DMU_BONUS_BLKID) 641 match_offset = TRUE; 642 break; 643 case THT_ZAP: 644 match_offset = TRUE; 645 break; 646 case THT_NEWOBJECT: 647 match_object = TRUE; 648 break; 649 default: 650 ASSERT(!"bad txh_type"); 651 } 652 } 653 if (match_object && match_offset) { 654 DB_DNODE_EXIT(db); 655 return; 656 } 657 } 658 DB_DNODE_EXIT(db); 659 panic("dirtying dbuf obj=%llx lvl=%u blkid=%llx but not tx_held\n", 660 (u_longlong_t)db->db.db_object, db->db_level, 661 (u_longlong_t)db->db_blkid); 662 } 663 #endif 664 665 /* 666 * If we can't do 10 iops, something is wrong. Let us go ahead 667 * and hit zfs_dirty_data_max. 668 */ 669 hrtime_t zfs_delay_max_ns = MSEC2NSEC(100); 670 int zfs_delay_resolution_ns = 100 * 1000; /* 100 microseconds */ 671 672 /* 673 * We delay transactions when we've determined that the backend storage 674 * isn't able to accommodate the rate of incoming writes. 675 * 676 * If there is already a transaction waiting, we delay relative to when 677 * that transaction finishes waiting. This way the calculated min_time 678 * is independent of the number of threads concurrently executing 679 * transactions. 680 * 681 * If we are the only waiter, wait relative to when the transaction 682 * started, rather than the current time. This credits the transaction for 683 * "time already served", e.g. reading indirect blocks. 684 * 685 * The minimum time for a transaction to take is calculated as: 686 * min_time = scale * (dirty - min) / (max - dirty) 687 * min_time is then capped at zfs_delay_max_ns. 688 * 689 * The delay has two degrees of freedom that can be adjusted via tunables. 690 * The percentage of dirty data at which we start to delay is defined by 691 * zfs_delay_min_dirty_percent. This should typically be at or above 692 * zfs_vdev_async_write_active_max_dirty_percent so that we only start to 693 * delay after writing at full speed has failed to keep up with the incoming 694 * write rate. The scale of the curve is defined by zfs_delay_scale. Roughly 695 * speaking, this variable determines the amount of delay at the midpoint of 696 * the curve. 697 * 698 * delay 699 * 10ms +-------------------------------------------------------------*+ 700 * | *| 701 * 9ms + *+ 702 * | *| 703 * 8ms + *+ 704 * | * | 705 * 7ms + * + 706 * | * | 707 * 6ms + * + 708 * | * | 709 * 5ms + * + 710 * | * | 711 * 4ms + * + 712 * | * | 713 * 3ms + * + 714 * | * | 715 * 2ms + (midpoint) * + 716 * | | ** | 717 * 1ms + v *** + 718 * | zfs_delay_scale ----------> ******** | 719 * 0 +-------------------------------------*********----------------+ 720 * 0% <- zfs_dirty_data_max -> 100% 721 * 722 * Note that since the delay is added to the outstanding time remaining on the 723 * most recent transaction, the delay is effectively the inverse of IOPS. 724 * Here the midpoint of 500us translates to 2000 IOPS. The shape of the curve 725 * was chosen such that small changes in the amount of accumulated dirty data 726 * in the first 3/4 of the curve yield relatively small differences in the 727 * amount of delay. 728 * 729 * The effects can be easier to understand when the amount of delay is 730 * represented on a log scale: 731 * 732 * delay 733 * 100ms +-------------------------------------------------------------++ 734 * + + 735 * | | 736 * + *+ 737 * 10ms + *+ 738 * + ** + 739 * | (midpoint) ** | 740 * + | ** + 741 * 1ms + v **** + 742 * + zfs_delay_scale ----------> ***** + 743 * | **** | 744 * + **** + 745 * 100us + ** + 746 * + * + 747 * | * | 748 * + * + 749 * 10us + * + 750 * + + 751 * | | 752 * + + 753 * +--------------------------------------------------------------+ 754 * 0% <- zfs_dirty_data_max -> 100% 755 * 756 * Note here that only as the amount of dirty data approaches its limit does 757 * the delay start to increase rapidly. The goal of a properly tuned system 758 * should be to keep the amount of dirty data out of that range by first 759 * ensuring that the appropriate limits are set for the I/O scheduler to reach 760 * optimal throughput on the backend storage, and then by changing the value 761 * of zfs_delay_scale to increase the steepness of the curve. 762 */ 763 static void 764 dmu_tx_delay(dmu_tx_t *tx, uint64_t dirty) 765 { 766 dsl_pool_t *dp = tx->tx_pool; 767 uint64_t delay_min_bytes = 768 zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; 769 hrtime_t wakeup, min_tx_time, now; 770 771 if (dirty <= delay_min_bytes) 772 return; 773 774 /* 775 * The caller has already waited until we are under the max. 776 * We make them pass us the amount of dirty data so we don't 777 * have to handle the case of it being >= the max, which could 778 * cause a divide-by-zero if it's == the max. 779 */ 780 ASSERT3U(dirty, <, zfs_dirty_data_max); 781 782 now = gethrtime(); 783 min_tx_time = zfs_delay_scale * 784 (dirty - delay_min_bytes) / (zfs_dirty_data_max - dirty); 785 if (now > tx->tx_start + min_tx_time) 786 return; 787 788 min_tx_time = MIN(min_tx_time, zfs_delay_max_ns); 789 790 DTRACE_PROBE3(delay__mintime, dmu_tx_t *, tx, uint64_t, dirty, 791 uint64_t, min_tx_time); 792 793 mutex_enter(&dp->dp_lock); 794 wakeup = MAX(tx->tx_start + min_tx_time, 795 dp->dp_last_wakeup + min_tx_time); 796 dp->dp_last_wakeup = wakeup; 797 mutex_exit(&dp->dp_lock); 798 799 #ifdef _KERNEL 800 mutex_enter(&curthread->t_delay_lock); 801 while (cv_timedwait_hires(&curthread->t_delay_cv, 802 &curthread->t_delay_lock, wakeup, zfs_delay_resolution_ns, 803 CALLOUT_FLAG_ABSOLUTE | CALLOUT_FLAG_ROUNDUP) > 0) 804 continue; 805 mutex_exit(&curthread->t_delay_lock); 806 #else 807 hrtime_t delta = wakeup - gethrtime(); 808 struct timespec ts; 809 ts.tv_sec = delta / NANOSEC; 810 ts.tv_nsec = delta % NANOSEC; 811 (void) nanosleep(&ts, NULL); 812 #endif 813 } 814 815 /* 816 * This routine attempts to assign the transaction to a transaction group. 817 * To do so, we must determine if there is sufficient free space on disk. 818 * 819 * If this is a "netfree" transaction (i.e. we called dmu_tx_mark_netfree() 820 * on it), then it is assumed that there is sufficient free space, 821 * unless there's insufficient slop space in the pool (see the comment 822 * above spa_slop_shift in spa_misc.c). 823 * 824 * If it is not a "netfree" transaction, then if the data already on disk 825 * is over the allowed usage (e.g. quota), this will fail with EDQUOT or 826 * ENOSPC. Otherwise, if the current rough estimate of pending changes, 827 * plus the rough estimate of this transaction's changes, may exceed the 828 * allowed usage, then this will fail with ERESTART, which will cause the 829 * caller to wait for the pending changes to be written to disk (by waiting 830 * for the next TXG to open), and then check the space usage again. 831 * 832 * The rough estimate of pending changes is comprised of the sum of: 833 * 834 * - this transaction's holds' txh_space_towrite 835 * 836 * - dd_tempreserved[], which is the sum of in-flight transactions' 837 * holds' txh_space_towrite (i.e. those transactions that have called 838 * dmu_tx_assign() but not yet called dmu_tx_commit()). 839 * 840 * - dd_space_towrite[], which is the amount of dirtied dbufs. 841 * 842 * Note that all of these values are inflated by spa_get_worst_case_asize(), 843 * which means that we may get ERESTART well before we are actually in danger 844 * of running out of space, but this also mitigates any small inaccuracies 845 * in the rough estimate (e.g. txh_space_towrite doesn't take into account 846 * indirect blocks, and dd_space_towrite[] doesn't take into account changes 847 * to the MOS). 848 * 849 * Note that due to this algorithm, it is possible to exceed the allowed 850 * usage by one transaction. Also, as we approach the allowed usage, 851 * we will allow a very limited amount of changes into each TXG, thus 852 * decreasing performance. 853 */ 854 static int 855 dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how) 856 { 857 spa_t *spa = tx->tx_pool->dp_spa; 858 859 ASSERT0(tx->tx_txg); 860 861 if (tx->tx_err) 862 return (tx->tx_err); 863 864 if (spa_suspended(spa)) { 865 /* 866 * If the user has indicated a blocking failure mode 867 * then return ERESTART which will block in dmu_tx_wait(). 868 * Otherwise, return EIO so that an error can get 869 * propagated back to the VOP calls. 870 * 871 * Note that we always honor the txg_how flag regardless 872 * of the failuremode setting. 873 */ 874 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE && 875 txg_how != TXG_WAIT) 876 return (SET_ERROR(EIO)); 877 878 return (SET_ERROR(ERESTART)); 879 } 880 881 if (!tx->tx_waited && 882 dsl_pool_need_dirty_delay(tx->tx_pool)) { 883 tx->tx_wait_dirty = B_TRUE; 884 return (SET_ERROR(ERESTART)); 885 } 886 887 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh); 888 tx->tx_needassign_txh = NULL; 889 890 /* 891 * NB: No error returns are allowed after txg_hold_open, but 892 * before processing the dnode holds, due to the 893 * dmu_tx_unassign() logic. 894 */ 895 896 uint64_t towrite = 0; 897 uint64_t tohold = 0; 898 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 899 txh = list_next(&tx->tx_holds, txh)) { 900 dnode_t *dn = txh->txh_dnode; 901 if (dn != NULL) { 902 mutex_enter(&dn->dn_mtx); 903 if (dn->dn_assigned_txg == tx->tx_txg - 1) { 904 mutex_exit(&dn->dn_mtx); 905 tx->tx_needassign_txh = txh; 906 return (SET_ERROR(ERESTART)); 907 } 908 if (dn->dn_assigned_txg == 0) 909 dn->dn_assigned_txg = tx->tx_txg; 910 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 911 (void) refcount_add(&dn->dn_tx_holds, tx); 912 mutex_exit(&dn->dn_mtx); 913 } 914 towrite += refcount_count(&txh->txh_space_towrite); 915 tohold += refcount_count(&txh->txh_memory_tohold); 916 } 917 918 /* needed allocation: worst-case estimate of write space */ 919 uint64_t asize = spa_get_worst_case_asize(tx->tx_pool->dp_spa, towrite); 920 /* calculate memory footprint estimate */ 921 uint64_t memory = towrite + tohold; 922 923 if (tx->tx_dir != NULL && asize != 0) { 924 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory, 925 asize, tx->tx_netfree, &tx->tx_tempreserve_cookie, tx); 926 if (err != 0) 927 return (err); 928 } 929 930 return (0); 931 } 932 933 static void 934 dmu_tx_unassign(dmu_tx_t *tx) 935 { 936 if (tx->tx_txg == 0) 937 return; 938 939 txg_rele_to_quiesce(&tx->tx_txgh); 940 941 /* 942 * Walk the transaction's hold list, removing the hold on the 943 * associated dnode, and notifying waiters if the refcount drops to 0. 944 */ 945 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); 946 txh != tx->tx_needassign_txh; 947 txh = list_next(&tx->tx_holds, txh)) { 948 dnode_t *dn = txh->txh_dnode; 949 950 if (dn == NULL) 951 continue; 952 mutex_enter(&dn->dn_mtx); 953 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 954 955 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) { 956 dn->dn_assigned_txg = 0; 957 cv_broadcast(&dn->dn_notxholds); 958 } 959 mutex_exit(&dn->dn_mtx); 960 } 961 962 txg_rele_to_sync(&tx->tx_txgh); 963 964 tx->tx_lasttried_txg = tx->tx_txg; 965 tx->tx_txg = 0; 966 } 967 968 /* 969 * Assign tx to a transaction group. txg_how can be one of: 970 * 971 * (1) TXG_WAIT. If the current open txg is full, waits until there's 972 * a new one. This should be used when you're not holding locks. 973 * It will only fail if we're truly out of space (or over quota). 974 * 975 * (2) TXG_NOWAIT. If we can't assign into the current open txg without 976 * blocking, returns immediately with ERESTART. This should be used 977 * whenever you're holding locks. On an ERESTART error, the caller 978 * should drop locks, do a dmu_tx_wait(tx), and try again. 979 * 980 * (3) TXG_WAITED. Like TXG_NOWAIT, but indicates that dmu_tx_wait() 981 * has already been called on behalf of this operation (though 982 * most likely on a different tx). 983 */ 984 int 985 dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how) 986 { 987 int err; 988 989 ASSERT(tx->tx_txg == 0); 990 ASSERT(txg_how == TXG_WAIT || txg_how == TXG_NOWAIT || 991 txg_how == TXG_WAITED); 992 ASSERT(!dsl_pool_sync_context(tx->tx_pool)); 993 994 /* If we might wait, we must not hold the config lock. */ 995 ASSERT(txg_how != TXG_WAIT || !dsl_pool_config_held(tx->tx_pool)); 996 997 if (txg_how == TXG_WAITED) 998 tx->tx_waited = B_TRUE; 999 1000 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) { 1001 dmu_tx_unassign(tx); 1002 1003 if (err != ERESTART || txg_how != TXG_WAIT) 1004 return (err); 1005 1006 dmu_tx_wait(tx); 1007 } 1008 1009 txg_rele_to_quiesce(&tx->tx_txgh); 1010 1011 return (0); 1012 } 1013 1014 void 1015 dmu_tx_wait(dmu_tx_t *tx) 1016 { 1017 spa_t *spa = tx->tx_pool->dp_spa; 1018 dsl_pool_t *dp = tx->tx_pool; 1019 1020 ASSERT(tx->tx_txg == 0); 1021 ASSERT(!dsl_pool_config_held(tx->tx_pool)); 1022 1023 if (tx->tx_wait_dirty) { 1024 /* 1025 * dmu_tx_try_assign() has determined that we need to wait 1026 * because we've consumed much or all of the dirty buffer 1027 * space. 1028 */ 1029 mutex_enter(&dp->dp_lock); 1030 while (dp->dp_dirty_total >= zfs_dirty_data_max) 1031 cv_wait(&dp->dp_spaceavail_cv, &dp->dp_lock); 1032 uint64_t dirty = dp->dp_dirty_total; 1033 mutex_exit(&dp->dp_lock); 1034 1035 dmu_tx_delay(tx, dirty); 1036 1037 tx->tx_wait_dirty = B_FALSE; 1038 1039 /* 1040 * Note: setting tx_waited only has effect if the caller 1041 * used TX_WAIT. Otherwise they are going to destroy 1042 * this tx and try again. The common case, zfs_write(), 1043 * uses TX_WAIT. 1044 */ 1045 tx->tx_waited = B_TRUE; 1046 } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { 1047 /* 1048 * If the pool is suspended we need to wait until it 1049 * is resumed. Note that it's possible that the pool 1050 * has become active after this thread has tried to 1051 * obtain a tx. If that's the case then tx_lasttried_txg 1052 * would not have been set. 1053 */ 1054 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1055 } else if (tx->tx_needassign_txh) { 1056 /* 1057 * A dnode is assigned to the quiescing txg. Wait for its 1058 * transaction to complete. 1059 */ 1060 dnode_t *dn = tx->tx_needassign_txh->txh_dnode; 1061 1062 mutex_enter(&dn->dn_mtx); 1063 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1) 1064 cv_wait(&dn->dn_notxholds, &dn->dn_mtx); 1065 mutex_exit(&dn->dn_mtx); 1066 tx->tx_needassign_txh = NULL; 1067 } else { 1068 txg_wait_open(tx->tx_pool, tx->tx_lasttried_txg + 1); 1069 } 1070 } 1071 1072 static void 1073 dmu_tx_destroy(dmu_tx_t *tx) 1074 { 1075 dmu_tx_hold_t *txh; 1076 1077 while ((txh = list_head(&tx->tx_holds)) != NULL) { 1078 dnode_t *dn = txh->txh_dnode; 1079 1080 list_remove(&tx->tx_holds, txh); 1081 refcount_destroy_many(&txh->txh_space_towrite, 1082 refcount_count(&txh->txh_space_towrite)); 1083 refcount_destroy_many(&txh->txh_memory_tohold, 1084 refcount_count(&txh->txh_memory_tohold)); 1085 kmem_free(txh, sizeof (dmu_tx_hold_t)); 1086 if (dn != NULL) 1087 dnode_rele(dn, tx); 1088 } 1089 1090 list_destroy(&tx->tx_callbacks); 1091 list_destroy(&tx->tx_holds); 1092 kmem_free(tx, sizeof (dmu_tx_t)); 1093 } 1094 1095 void 1096 dmu_tx_commit(dmu_tx_t *tx) 1097 { 1098 ASSERT(tx->tx_txg != 0); 1099 1100 /* 1101 * Go through the transaction's hold list and remove holds on 1102 * associated dnodes, notifying waiters if no holds remain. 1103 */ 1104 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 1105 txh = list_next(&tx->tx_holds, txh)) { 1106 dnode_t *dn = txh->txh_dnode; 1107 1108 if (dn == NULL) 1109 continue; 1110 1111 mutex_enter(&dn->dn_mtx); 1112 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 1113 1114 if (refcount_remove(&dn->dn_tx_holds, tx) == 0) { 1115 dn->dn_assigned_txg = 0; 1116 cv_broadcast(&dn->dn_notxholds); 1117 } 1118 mutex_exit(&dn->dn_mtx); 1119 } 1120 1121 if (tx->tx_tempreserve_cookie) 1122 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx); 1123 1124 if (!list_is_empty(&tx->tx_callbacks)) 1125 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks); 1126 1127 if (tx->tx_anyobj == FALSE) 1128 txg_rele_to_sync(&tx->tx_txgh); 1129 1130 dmu_tx_destroy(tx); 1131 } 1132 1133 void 1134 dmu_tx_abort(dmu_tx_t *tx) 1135 { 1136 ASSERT(tx->tx_txg == 0); 1137 1138 /* 1139 * Call any registered callbacks with an error code. 1140 */ 1141 if (!list_is_empty(&tx->tx_callbacks)) 1142 dmu_tx_do_callbacks(&tx->tx_callbacks, ECANCELED); 1143 1144 dmu_tx_destroy(tx); 1145 } 1146 1147 uint64_t 1148 dmu_tx_get_txg(dmu_tx_t *tx) 1149 { 1150 ASSERT(tx->tx_txg != 0); 1151 return (tx->tx_txg); 1152 } 1153 1154 dsl_pool_t * 1155 dmu_tx_pool(dmu_tx_t *tx) 1156 { 1157 ASSERT(tx->tx_pool != NULL); 1158 return (tx->tx_pool); 1159 } 1160 1161 void 1162 dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data) 1163 { 1164 dmu_tx_callback_t *dcb; 1165 1166 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_SLEEP); 1167 1168 dcb->dcb_func = func; 1169 dcb->dcb_data = data; 1170 1171 list_insert_tail(&tx->tx_callbacks, dcb); 1172 } 1173 1174 /* 1175 * Call all the commit callbacks on a list, with a given error code. 1176 */ 1177 void 1178 dmu_tx_do_callbacks(list_t *cb_list, int error) 1179 { 1180 dmu_tx_callback_t *dcb; 1181 1182 while ((dcb = list_head(cb_list)) != NULL) { 1183 list_remove(cb_list, dcb); 1184 dcb->dcb_func(dcb->dcb_data, error); 1185 kmem_free(dcb, sizeof (dmu_tx_callback_t)); 1186 } 1187 } 1188 1189 /* 1190 * Interface to hold a bunch of attributes. 1191 * used for creating new files. 1192 * attrsize is the total size of all attributes 1193 * to be added during object creation 1194 * 1195 * For updating/adding a single attribute dmu_tx_hold_sa() should be used. 1196 */ 1197 1198 /* 1199 * hold necessary attribute name for attribute registration. 1200 * should be a very rare case where this is needed. If it does 1201 * happen it would only happen on the first write to the file system. 1202 */ 1203 static void 1204 dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx) 1205 { 1206 if (!sa->sa_need_attr_registration) 1207 return; 1208 1209 for (int i = 0; i != sa->sa_num_attrs; i++) { 1210 if (!sa->sa_attr_table[i].sa_registered) { 1211 if (sa->sa_reg_attr_obj) 1212 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj, 1213 B_TRUE, sa->sa_attr_table[i].sa_name); 1214 else 1215 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 1216 B_TRUE, sa->sa_attr_table[i].sa_name); 1217 } 1218 } 1219 } 1220 1221 void 1222 dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object) 1223 { 1224 dmu_tx_hold_t *txh = dmu_tx_hold_object_impl(tx, 1225 tx->tx_objset, object, THT_SPILL, 0, 0); 1226 1227 (void) refcount_add_many(&txh->txh_space_towrite, 1228 SPA_OLD_MAXBLOCKSIZE, FTAG); 1229 } 1230 1231 void 1232 dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize) 1233 { 1234 sa_os_t *sa = tx->tx_objset->os_sa; 1235 1236 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1237 1238 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1239 return; 1240 1241 if (tx->tx_objset->os_sa->sa_layout_attr_obj) { 1242 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1243 } else { 1244 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1245 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1246 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1247 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1248 } 1249 1250 dmu_tx_sa_registration_hold(sa, tx); 1251 1252 if (attrsize <= DN_MAX_BONUSLEN && !sa->sa_force_spill) 1253 return; 1254 1255 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT, 1256 THT_SPILL, 0, 0); 1257 } 1258 1259 /* 1260 * Hold SA attribute 1261 * 1262 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size) 1263 * 1264 * variable_size is the total size of all variable sized attributes 1265 * passed to this function. It is not the total size of all 1266 * variable size attributes that *may* exist on this object. 1267 */ 1268 void 1269 dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow) 1270 { 1271 uint64_t object; 1272 sa_os_t *sa = tx->tx_objset->os_sa; 1273 1274 ASSERT(hdl != NULL); 1275 1276 object = sa_handle_object(hdl); 1277 1278 dmu_tx_hold_bonus(tx, object); 1279 1280 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1281 return; 1282 1283 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 || 1284 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) { 1285 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1286 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1287 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1288 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1289 } 1290 1291 dmu_tx_sa_registration_hold(sa, tx); 1292 1293 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj) 1294 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1295 1296 if (sa->sa_force_spill || may_grow || hdl->sa_spill) { 1297 ASSERT(tx->tx_txg == 0); 1298 dmu_tx_hold_spill(tx, object); 1299 } else { 1300 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus; 1301 dnode_t *dn; 1302 1303 DB_DNODE_ENTER(db); 1304 dn = DB_DNODE(db); 1305 if (dn->dn_have_spill) { 1306 ASSERT(tx->tx_txg == 0); 1307 dmu_tx_hold_spill(tx, object); 1308 } 1309 DB_DNODE_EXIT(db); 1310 } 1311 } 1312