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) zfs_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) zfs_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 zfs_refcount_create(&txh->txh_space_towrite); 121 zfs_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) zfs_refcount_add_many(&txh->txh_space_towrite, len, FTAG); 217 218 if (zfs_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) zfs_refcount_add_many(&txh->txh_space_towrite, DNODE_MIN_SIZE, 284 FTAG); 285 } 286 287 void 288 dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len) 289 { 290 dmu_tx_hold_t *txh; 291 292 ASSERT0(tx->tx_txg); 293 ASSERT3U(len, <=, DMU_MAX_ACCESS); 294 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 295 296 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 297 object, THT_WRITE, off, len); 298 if (txh != NULL) { 299 dmu_tx_count_write(txh, off, len); 300 dmu_tx_count_dnode(txh); 301 } 302 } 303 304 void 305 dmu_tx_hold_remap_l1indirect(dmu_tx_t *tx, uint64_t object) 306 { 307 dmu_tx_hold_t *txh; 308 309 ASSERT(tx->tx_txg == 0); 310 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 311 object, THT_WRITE, 0, 0); 312 if (txh == NULL) 313 return; 314 315 dnode_t *dn = txh->txh_dnode; 316 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 317 1ULL << dn->dn_indblkshift, FTAG); 318 dmu_tx_count_dnode(txh); 319 } 320 321 void 322 dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len) 323 { 324 dmu_tx_hold_t *txh; 325 326 ASSERT0(tx->tx_txg); 327 ASSERT3U(len, <=, DMU_MAX_ACCESS); 328 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 329 330 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_WRITE, off, len); 331 if (txh != NULL) { 332 dmu_tx_count_write(txh, off, len); 333 dmu_tx_count_dnode(txh); 334 } 335 } 336 337 /* 338 * This function marks the transaction as being a "net free". The end 339 * result is that refquotas will be disabled for this transaction, and 340 * this transaction will be able to use half of the pool space overhead 341 * (see dsl_pool_adjustedsize()). Therefore this function should only 342 * be called for transactions that we expect will not cause a net increase 343 * in the amount of space used (but it's OK if that is occasionally not true). 344 */ 345 void 346 dmu_tx_mark_netfree(dmu_tx_t *tx) 347 { 348 tx->tx_netfree = B_TRUE; 349 } 350 351 static void 352 dmu_tx_hold_free_impl(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 353 { 354 dmu_tx_t *tx; 355 dnode_t *dn; 356 int err; 357 358 tx = txh->txh_tx; 359 ASSERT(tx->tx_txg == 0); 360 361 dn = txh->txh_dnode; 362 dmu_tx_count_dnode(txh); 363 364 if (off >= (dn->dn_maxblkid + 1) * dn->dn_datablksz) 365 return; 366 if (len == DMU_OBJECT_END) 367 len = (dn->dn_maxblkid + 1) * dn->dn_datablksz - off; 368 369 /* 370 * For i/o error checking, we read the first and last level-0 371 * blocks if they are not aligned, and all the level-1 blocks. 372 * 373 * Note: dbuf_free_range() assumes that we have not instantiated 374 * any level-0 dbufs that will be completely freed. Therefore we must 375 * exercise care to not read or count the first and last blocks 376 * if they are blocksize-aligned. 377 */ 378 if (dn->dn_datablkshift == 0) { 379 if (off != 0 || len < dn->dn_datablksz) 380 dmu_tx_count_write(txh, 0, dn->dn_datablksz); 381 } else { 382 /* first block will be modified if it is not aligned */ 383 if (!IS_P2ALIGNED(off, 1 << dn->dn_datablkshift)) 384 dmu_tx_count_write(txh, off, 1); 385 /* last block will be modified if it is not aligned */ 386 if (!IS_P2ALIGNED(off + len, 1 << dn->dn_datablkshift)) 387 dmu_tx_count_write(txh, off + len, 1); 388 } 389 390 /* 391 * Check level-1 blocks. 392 */ 393 if (dn->dn_nlevels > 1) { 394 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 395 SPA_BLKPTRSHIFT; 396 uint64_t start = off >> shift; 397 uint64_t end = (off + len) >> shift; 398 399 ASSERT(dn->dn_indblkshift != 0); 400 401 /* 402 * dnode_reallocate() can result in an object with indirect 403 * blocks having an odd data block size. In this case, 404 * just check the single block. 405 */ 406 if (dn->dn_datablkshift == 0) 407 start = end = 0; 408 409 zio_t *zio = zio_root(tx->tx_pool->dp_spa, 410 NULL, NULL, ZIO_FLAG_CANFAIL); 411 for (uint64_t i = start; i <= end; i++) { 412 uint64_t ibyte = i << shift; 413 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0); 414 i = ibyte >> shift; 415 if (err == ESRCH || i > end) 416 break; 417 if (err != 0) { 418 tx->tx_err = err; 419 (void) zio_wait(zio); 420 return; 421 } 422 423 (void) zfs_refcount_add_many(&txh->txh_memory_tohold, 424 1 << dn->dn_indblkshift, FTAG); 425 426 err = dmu_tx_check_ioerr(zio, dn, 1, i); 427 if (err != 0) { 428 tx->tx_err = err; 429 (void) zio_wait(zio); 430 return; 431 } 432 } 433 err = zio_wait(zio); 434 if (err != 0) { 435 tx->tx_err = err; 436 return; 437 } 438 } 439 } 440 441 void 442 dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len) 443 { 444 dmu_tx_hold_t *txh; 445 446 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 447 object, THT_FREE, off, len); 448 if (txh != NULL) 449 (void) dmu_tx_hold_free_impl(txh, off, len); 450 } 451 452 void 453 dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, uint64_t len) 454 { 455 dmu_tx_hold_t *txh; 456 457 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_FREE, off, len); 458 if (txh != NULL) 459 (void) dmu_tx_hold_free_impl(txh, off, len); 460 } 461 462 static void 463 dmu_tx_hold_zap_impl(dmu_tx_hold_t *txh, const char *name) 464 { 465 dmu_tx_t *tx = txh->txh_tx; 466 dnode_t *dn; 467 int err; 468 469 ASSERT(tx->tx_txg == 0); 470 471 dn = txh->txh_dnode; 472 473 dmu_tx_count_dnode(txh); 474 475 /* 476 * Modifying a almost-full microzap is around the worst case (128KB) 477 * 478 * If it is a fat zap, the worst case would be 7*16KB=112KB: 479 * - 3 blocks overwritten: target leaf, ptrtbl block, header block 480 * - 4 new blocks written if adding: 481 * - 2 blocks for possibly split leaves, 482 * - 2 grown ptrtbl blocks 483 */ 484 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 485 MZAP_MAX_BLKSZ, FTAG); 486 487 if (dn == NULL) 488 return; 489 490 ASSERT3P(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP); 491 492 if (dn->dn_maxblkid == 0 || name == NULL) { 493 /* 494 * This is a microzap (only one block), or we don't know 495 * the name. Check the first block for i/o errors. 496 */ 497 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 498 if (err != 0) { 499 tx->tx_err = err; 500 } 501 } else { 502 /* 503 * Access the name so that we'll check for i/o errors to 504 * the leaf blocks, etc. We ignore ENOENT, as this name 505 * may not yet exist. 506 */ 507 err = zap_lookup_by_dnode(dn, name, 8, 0, NULL); 508 if (err == EIO || err == ECKSUM || err == ENXIO) { 509 tx->tx_err = err; 510 } 511 } 512 } 513 514 void 515 dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name) 516 { 517 dmu_tx_hold_t *txh; 518 519 ASSERT0(tx->tx_txg); 520 521 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 522 object, THT_ZAP, add, (uintptr_t)name); 523 if (txh != NULL) 524 dmu_tx_hold_zap_impl(txh, name); 525 } 526 527 void 528 dmu_tx_hold_zap_by_dnode(dmu_tx_t *tx, dnode_t *dn, int add, const char *name) 529 { 530 dmu_tx_hold_t *txh; 531 532 ASSERT0(tx->tx_txg); 533 ASSERT(dn != NULL); 534 535 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_ZAP, add, (uintptr_t)name); 536 if (txh != NULL) 537 dmu_tx_hold_zap_impl(txh, name); 538 } 539 540 void 541 dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object) 542 { 543 dmu_tx_hold_t *txh; 544 545 ASSERT(tx->tx_txg == 0); 546 547 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 548 object, THT_BONUS, 0, 0); 549 if (txh) 550 dmu_tx_count_dnode(txh); 551 } 552 553 void 554 dmu_tx_hold_bonus_by_dnode(dmu_tx_t *tx, dnode_t *dn) 555 { 556 dmu_tx_hold_t *txh; 557 558 ASSERT0(tx->tx_txg); 559 560 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_BONUS, 0, 0); 561 if (txh) 562 dmu_tx_count_dnode(txh); 563 } 564 565 void 566 dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space) 567 { 568 dmu_tx_hold_t *txh; 569 ASSERT(tx->tx_txg == 0); 570 571 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 572 DMU_NEW_OBJECT, THT_SPACE, space, 0); 573 574 (void) zfs_refcount_add_many(&txh->txh_space_towrite, space, FTAG); 575 } 576 577 #ifdef ZFS_DEBUG 578 void 579 dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db) 580 { 581 boolean_t match_object = B_FALSE; 582 boolean_t match_offset = B_FALSE; 583 584 DB_DNODE_ENTER(db); 585 dnode_t *dn = DB_DNODE(db); 586 ASSERT(tx->tx_txg != 0); 587 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset); 588 ASSERT3U(dn->dn_object, ==, db->db.db_object); 589 590 if (tx->tx_anyobj) { 591 DB_DNODE_EXIT(db); 592 return; 593 } 594 595 /* XXX No checking on the meta dnode for now */ 596 if (db->db.db_object == DMU_META_DNODE_OBJECT) { 597 DB_DNODE_EXIT(db); 598 return; 599 } 600 601 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 602 txh = list_next(&tx->tx_holds, txh)) { 603 ASSERT(dn == NULL || dn->dn_assigned_txg == tx->tx_txg); 604 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT) 605 match_object = TRUE; 606 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) { 607 int datablkshift = dn->dn_datablkshift ? 608 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT; 609 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 610 int shift = datablkshift + epbs * db->db_level; 611 uint64_t beginblk = shift >= 64 ? 0 : 612 (txh->txh_arg1 >> shift); 613 uint64_t endblk = shift >= 64 ? 0 : 614 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift); 615 uint64_t blkid = db->db_blkid; 616 617 /* XXX txh_arg2 better not be zero... */ 618 619 dprintf("found txh type %x beginblk=%llx endblk=%llx\n", 620 txh->txh_type, beginblk, endblk); 621 622 switch (txh->txh_type) { 623 case THT_WRITE: 624 if (blkid >= beginblk && blkid <= endblk) 625 match_offset = TRUE; 626 /* 627 * We will let this hold work for the bonus 628 * or spill buffer so that we don't need to 629 * hold it when creating a new object. 630 */ 631 if (blkid == DMU_BONUS_BLKID || 632 blkid == DMU_SPILL_BLKID) 633 match_offset = TRUE; 634 /* 635 * They might have to increase nlevels, 636 * thus dirtying the new TLIBs. Or the 637 * might have to change the block size, 638 * thus dirying the new lvl=0 blk=0. 639 */ 640 if (blkid == 0) 641 match_offset = TRUE; 642 break; 643 case THT_FREE: 644 /* 645 * We will dirty all the level 1 blocks in 646 * the free range and perhaps the first and 647 * last level 0 block. 648 */ 649 if (blkid >= beginblk && (blkid <= endblk || 650 txh->txh_arg2 == DMU_OBJECT_END)) 651 match_offset = TRUE; 652 break; 653 case THT_SPILL: 654 if (blkid == DMU_SPILL_BLKID) 655 match_offset = TRUE; 656 break; 657 case THT_BONUS: 658 if (blkid == DMU_BONUS_BLKID) 659 match_offset = TRUE; 660 break; 661 case THT_ZAP: 662 match_offset = TRUE; 663 break; 664 case THT_NEWOBJECT: 665 match_object = TRUE; 666 break; 667 default: 668 ASSERT(!"bad txh_type"); 669 } 670 } 671 if (match_object && match_offset) { 672 DB_DNODE_EXIT(db); 673 return; 674 } 675 } 676 DB_DNODE_EXIT(db); 677 panic("dirtying dbuf obj=%llx lvl=%u blkid=%llx but not tx_held\n", 678 (u_longlong_t)db->db.db_object, db->db_level, 679 (u_longlong_t)db->db_blkid); 680 } 681 #endif 682 683 /* 684 * If we can't do 10 iops, something is wrong. Let us go ahead 685 * and hit zfs_dirty_data_max. 686 */ 687 hrtime_t zfs_delay_max_ns = MSEC2NSEC(100); 688 int zfs_delay_resolution_ns = 100 * 1000; /* 100 microseconds */ 689 690 /* 691 * We delay transactions when we've determined that the backend storage 692 * isn't able to accommodate the rate of incoming writes. 693 * 694 * If there is already a transaction waiting, we delay relative to when 695 * that transaction finishes waiting. This way the calculated min_time 696 * is independent of the number of threads concurrently executing 697 * transactions. 698 * 699 * If we are the only waiter, wait relative to when the transaction 700 * started, rather than the current time. This credits the transaction for 701 * "time already served", e.g. reading indirect blocks. 702 * 703 * The minimum time for a transaction to take is calculated as: 704 * min_time = scale * (dirty - min) / (max - dirty) 705 * min_time is then capped at zfs_delay_max_ns. 706 * 707 * The delay has two degrees of freedom that can be adjusted via tunables. 708 * The percentage of dirty data at which we start to delay is defined by 709 * zfs_delay_min_dirty_percent. This should typically be at or above 710 * zfs_vdev_async_write_active_max_dirty_percent so that we only start to 711 * delay after writing at full speed has failed to keep up with the incoming 712 * write rate. The scale of the curve is defined by zfs_delay_scale. Roughly 713 * speaking, this variable determines the amount of delay at the midpoint of 714 * the curve. 715 * 716 * delay 717 * 10ms +-------------------------------------------------------------*+ 718 * | *| 719 * 9ms + *+ 720 * | *| 721 * 8ms + *+ 722 * | * | 723 * 7ms + * + 724 * | * | 725 * 6ms + * + 726 * | * | 727 * 5ms + * + 728 * | * | 729 * 4ms + * + 730 * | * | 731 * 3ms + * + 732 * | * | 733 * 2ms + (midpoint) * + 734 * | | ** | 735 * 1ms + v *** + 736 * | zfs_delay_scale ----------> ******** | 737 * 0 +-------------------------------------*********----------------+ 738 * 0% <- zfs_dirty_data_max -> 100% 739 * 740 * Note that since the delay is added to the outstanding time remaining on the 741 * most recent transaction, the delay is effectively the inverse of IOPS. 742 * Here the midpoint of 500us translates to 2000 IOPS. The shape of the curve 743 * was chosen such that small changes in the amount of accumulated dirty data 744 * in the first 3/4 of the curve yield relatively small differences in the 745 * amount of delay. 746 * 747 * The effects can be easier to understand when the amount of delay is 748 * represented on a log scale: 749 * 750 * delay 751 * 100ms +-------------------------------------------------------------++ 752 * + + 753 * | | 754 * + *+ 755 * 10ms + *+ 756 * + ** + 757 * | (midpoint) ** | 758 * + | ** + 759 * 1ms + v **** + 760 * + zfs_delay_scale ----------> ***** + 761 * | **** | 762 * + **** + 763 * 100us + ** + 764 * + * + 765 * | * | 766 * + * + 767 * 10us + * + 768 * + + 769 * | | 770 * + + 771 * +--------------------------------------------------------------+ 772 * 0% <- zfs_dirty_data_max -> 100% 773 * 774 * Note here that only as the amount of dirty data approaches its limit does 775 * the delay start to increase rapidly. The goal of a properly tuned system 776 * should be to keep the amount of dirty data out of that range by first 777 * ensuring that the appropriate limits are set for the I/O scheduler to reach 778 * optimal throughput on the backend storage, and then by changing the value 779 * of zfs_delay_scale to increase the steepness of the curve. 780 */ 781 static void 782 dmu_tx_delay(dmu_tx_t *tx, uint64_t dirty) 783 { 784 dsl_pool_t *dp = tx->tx_pool; 785 uint64_t delay_min_bytes = 786 zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; 787 hrtime_t wakeup, min_tx_time, now; 788 789 if (dirty <= delay_min_bytes) 790 return; 791 792 /* 793 * The caller has already waited until we are under the max. 794 * We make them pass us the amount of dirty data so we don't 795 * have to handle the case of it being >= the max, which could 796 * cause a divide-by-zero if it's == the max. 797 */ 798 ASSERT3U(dirty, <, zfs_dirty_data_max); 799 800 now = gethrtime(); 801 min_tx_time = zfs_delay_scale * 802 (dirty - delay_min_bytes) / (zfs_dirty_data_max - dirty); 803 if (now > tx->tx_start + min_tx_time) 804 return; 805 806 min_tx_time = MIN(min_tx_time, zfs_delay_max_ns); 807 808 DTRACE_PROBE3(delay__mintime, dmu_tx_t *, tx, uint64_t, dirty, 809 uint64_t, min_tx_time); 810 811 mutex_enter(&dp->dp_lock); 812 wakeup = MAX(tx->tx_start + min_tx_time, 813 dp->dp_last_wakeup + min_tx_time); 814 dp->dp_last_wakeup = wakeup; 815 mutex_exit(&dp->dp_lock); 816 817 #ifdef _KERNEL 818 mutex_enter(&curthread->t_delay_lock); 819 while (cv_timedwait_hires(&curthread->t_delay_cv, 820 &curthread->t_delay_lock, wakeup, zfs_delay_resolution_ns, 821 CALLOUT_FLAG_ABSOLUTE | CALLOUT_FLAG_ROUNDUP) > 0) 822 continue; 823 mutex_exit(&curthread->t_delay_lock); 824 #else 825 hrtime_t delta = wakeup - gethrtime(); 826 struct timespec ts; 827 ts.tv_sec = delta / NANOSEC; 828 ts.tv_nsec = delta % NANOSEC; 829 (void) nanosleep(&ts, NULL); 830 #endif 831 } 832 833 /* 834 * This routine attempts to assign the transaction to a transaction group. 835 * To do so, we must determine if there is sufficient free space on disk. 836 * 837 * If this is a "netfree" transaction (i.e. we called dmu_tx_mark_netfree() 838 * on it), then it is assumed that there is sufficient free space, 839 * unless there's insufficient slop space in the pool (see the comment 840 * above spa_slop_shift in spa_misc.c). 841 * 842 * If it is not a "netfree" transaction, then if the data already on disk 843 * is over the allowed usage (e.g. quota), this will fail with EDQUOT or 844 * ENOSPC. Otherwise, if the current rough estimate of pending changes, 845 * plus the rough estimate of this transaction's changes, may exceed the 846 * allowed usage, then this will fail with ERESTART, which will cause the 847 * caller to wait for the pending changes to be written to disk (by waiting 848 * for the next TXG to open), and then check the space usage again. 849 * 850 * The rough estimate of pending changes is comprised of the sum of: 851 * 852 * - this transaction's holds' txh_space_towrite 853 * 854 * - dd_tempreserved[], which is the sum of in-flight transactions' 855 * holds' txh_space_towrite (i.e. those transactions that have called 856 * dmu_tx_assign() but not yet called dmu_tx_commit()). 857 * 858 * - dd_space_towrite[], which is the amount of dirtied dbufs. 859 * 860 * Note that all of these values are inflated by spa_get_worst_case_asize(), 861 * which means that we may get ERESTART well before we are actually in danger 862 * of running out of space, but this also mitigates any small inaccuracies 863 * in the rough estimate (e.g. txh_space_towrite doesn't take into account 864 * indirect blocks, and dd_space_towrite[] doesn't take into account changes 865 * to the MOS). 866 * 867 * Note that due to this algorithm, it is possible to exceed the allowed 868 * usage by one transaction. Also, as we approach the allowed usage, 869 * we will allow a very limited amount of changes into each TXG, thus 870 * decreasing performance. 871 */ 872 static int 873 dmu_tx_try_assign(dmu_tx_t *tx, uint64_t txg_how) 874 { 875 spa_t *spa = tx->tx_pool->dp_spa; 876 877 ASSERT0(tx->tx_txg); 878 879 if (tx->tx_err) 880 return (tx->tx_err); 881 882 if (spa_suspended(spa)) { 883 /* 884 * If the user has indicated a blocking failure mode 885 * then return ERESTART which will block in dmu_tx_wait(). 886 * Otherwise, return EIO so that an error can get 887 * propagated back to the VOP calls. 888 * 889 * Note that we always honor the txg_how flag regardless 890 * of the failuremode setting. 891 */ 892 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE && 893 !(txg_how & TXG_WAIT)) 894 return (SET_ERROR(EIO)); 895 896 return (SET_ERROR(ERESTART)); 897 } 898 899 if (!tx->tx_dirty_delayed && 900 dsl_pool_need_dirty_delay(tx->tx_pool)) { 901 tx->tx_wait_dirty = B_TRUE; 902 return (SET_ERROR(ERESTART)); 903 } 904 905 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh); 906 tx->tx_needassign_txh = NULL; 907 908 /* 909 * NB: No error returns are allowed after txg_hold_open, but 910 * before processing the dnode holds, due to the 911 * dmu_tx_unassign() logic. 912 */ 913 914 uint64_t towrite = 0; 915 uint64_t tohold = 0; 916 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 917 txh = list_next(&tx->tx_holds, txh)) { 918 dnode_t *dn = txh->txh_dnode; 919 if (dn != NULL) { 920 mutex_enter(&dn->dn_mtx); 921 if (dn->dn_assigned_txg == tx->tx_txg - 1) { 922 mutex_exit(&dn->dn_mtx); 923 tx->tx_needassign_txh = txh; 924 return (SET_ERROR(ERESTART)); 925 } 926 if (dn->dn_assigned_txg == 0) 927 dn->dn_assigned_txg = tx->tx_txg; 928 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 929 (void) zfs_refcount_add(&dn->dn_tx_holds, tx); 930 mutex_exit(&dn->dn_mtx); 931 } 932 towrite += zfs_refcount_count(&txh->txh_space_towrite); 933 tohold += zfs_refcount_count(&txh->txh_memory_tohold); 934 } 935 936 /* needed allocation: worst-case estimate of write space */ 937 uint64_t asize = spa_get_worst_case_asize(tx->tx_pool->dp_spa, towrite); 938 /* calculate memory footprint estimate */ 939 uint64_t memory = towrite + tohold; 940 941 if (tx->tx_dir != NULL && asize != 0) { 942 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory, 943 asize, tx->tx_netfree, &tx->tx_tempreserve_cookie, tx); 944 if (err != 0) 945 return (err); 946 } 947 948 return (0); 949 } 950 951 static void 952 dmu_tx_unassign(dmu_tx_t *tx) 953 { 954 if (tx->tx_txg == 0) 955 return; 956 957 txg_rele_to_quiesce(&tx->tx_txgh); 958 959 /* 960 * Walk the transaction's hold list, removing the hold on the 961 * associated dnode, and notifying waiters if the refcount drops to 0. 962 */ 963 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); 964 txh != tx->tx_needassign_txh; 965 txh = list_next(&tx->tx_holds, txh)) { 966 dnode_t *dn = txh->txh_dnode; 967 968 if (dn == NULL) 969 continue; 970 mutex_enter(&dn->dn_mtx); 971 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 972 973 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 974 dn->dn_assigned_txg = 0; 975 cv_broadcast(&dn->dn_notxholds); 976 } 977 mutex_exit(&dn->dn_mtx); 978 } 979 980 txg_rele_to_sync(&tx->tx_txgh); 981 982 tx->tx_lasttried_txg = tx->tx_txg; 983 tx->tx_txg = 0; 984 } 985 986 /* 987 * Assign tx to a transaction group; txg_how is a bitmask: 988 * 989 * If TXG_WAIT is set and the currently open txg is full, this function 990 * will wait until there's a new txg. This should be used when no locks 991 * are being held. With this bit set, this function will only fail if 992 * we're truly out of space (or over quota). 993 * 994 * If TXG_WAIT is *not* set and we can't assign into the currently open 995 * txg without blocking, this function will return immediately with 996 * ERESTART. This should be used whenever locks are being held. On an 997 * ERESTART error, the caller should drop all locks, call dmu_tx_wait(), 998 * and try again. 999 * 1000 * If TXG_NOTHROTTLE is set, this indicates that this tx should not be 1001 * delayed due on the ZFS Write Throttle (see comments in dsl_pool.c for 1002 * details on the throttle). This is used by the VFS operations, after 1003 * they have already called dmu_tx_wait() (though most likely on a 1004 * different tx). 1005 */ 1006 int 1007 dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how) 1008 { 1009 int err; 1010 1011 ASSERT(tx->tx_txg == 0); 1012 ASSERT0(txg_how & ~(TXG_WAIT | TXG_NOTHROTTLE)); 1013 ASSERT(!dsl_pool_sync_context(tx->tx_pool)); 1014 1015 /* If we might wait, we must not hold the config lock. */ 1016 IMPLY((txg_how & TXG_WAIT), !dsl_pool_config_held(tx->tx_pool)); 1017 1018 if ((txg_how & TXG_NOTHROTTLE)) 1019 tx->tx_dirty_delayed = B_TRUE; 1020 1021 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) { 1022 dmu_tx_unassign(tx); 1023 1024 if (err != ERESTART || !(txg_how & TXG_WAIT)) 1025 return (err); 1026 1027 dmu_tx_wait(tx); 1028 } 1029 1030 txg_rele_to_quiesce(&tx->tx_txgh); 1031 1032 return (0); 1033 } 1034 1035 void 1036 dmu_tx_wait(dmu_tx_t *tx) 1037 { 1038 spa_t *spa = tx->tx_pool->dp_spa; 1039 dsl_pool_t *dp = tx->tx_pool; 1040 1041 ASSERT(tx->tx_txg == 0); 1042 ASSERT(!dsl_pool_config_held(tx->tx_pool)); 1043 1044 if (tx->tx_wait_dirty) { 1045 /* 1046 * dmu_tx_try_assign() has determined that we need to wait 1047 * because we've consumed much or all of the dirty buffer 1048 * space. 1049 */ 1050 mutex_enter(&dp->dp_lock); 1051 while (dp->dp_dirty_total >= zfs_dirty_data_max) 1052 cv_wait(&dp->dp_spaceavail_cv, &dp->dp_lock); 1053 uint64_t dirty = dp->dp_dirty_total; 1054 mutex_exit(&dp->dp_lock); 1055 1056 dmu_tx_delay(tx, dirty); 1057 1058 tx->tx_wait_dirty = B_FALSE; 1059 1060 /* 1061 * Note: setting tx_dirty_delayed only has effect if the 1062 * caller used TX_WAIT. Otherwise they are going to 1063 * destroy this tx and try again. The common case, 1064 * zfs_write(), uses TX_WAIT. 1065 */ 1066 tx->tx_dirty_delayed = B_TRUE; 1067 } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { 1068 /* 1069 * If the pool is suspended we need to wait until it 1070 * is resumed. Note that it's possible that the pool 1071 * has become active after this thread has tried to 1072 * obtain a tx. If that's the case then tx_lasttried_txg 1073 * would not have been set. 1074 */ 1075 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1076 } else if (tx->tx_needassign_txh) { 1077 /* 1078 * A dnode is assigned to the quiescing txg. Wait for its 1079 * transaction to complete. 1080 */ 1081 dnode_t *dn = tx->tx_needassign_txh->txh_dnode; 1082 1083 mutex_enter(&dn->dn_mtx); 1084 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1) 1085 cv_wait(&dn->dn_notxholds, &dn->dn_mtx); 1086 mutex_exit(&dn->dn_mtx); 1087 tx->tx_needassign_txh = NULL; 1088 } else { 1089 /* 1090 * If we have a lot of dirty data just wait until we sync 1091 * out a TXG at which point we'll hopefully have synced 1092 * a portion of the changes. 1093 */ 1094 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1095 } 1096 } 1097 1098 static void 1099 dmu_tx_destroy(dmu_tx_t *tx) 1100 { 1101 dmu_tx_hold_t *txh; 1102 1103 while ((txh = list_head(&tx->tx_holds)) != NULL) { 1104 dnode_t *dn = txh->txh_dnode; 1105 1106 list_remove(&tx->tx_holds, txh); 1107 zfs_refcount_destroy_many(&txh->txh_space_towrite, 1108 zfs_refcount_count(&txh->txh_space_towrite)); 1109 zfs_refcount_destroy_many(&txh->txh_memory_tohold, 1110 zfs_refcount_count(&txh->txh_memory_tohold)); 1111 kmem_free(txh, sizeof (dmu_tx_hold_t)); 1112 if (dn != NULL) 1113 dnode_rele(dn, tx); 1114 } 1115 1116 list_destroy(&tx->tx_callbacks); 1117 list_destroy(&tx->tx_holds); 1118 kmem_free(tx, sizeof (dmu_tx_t)); 1119 } 1120 1121 void 1122 dmu_tx_commit(dmu_tx_t *tx) 1123 { 1124 ASSERT(tx->tx_txg != 0); 1125 1126 /* 1127 * Go through the transaction's hold list and remove holds on 1128 * associated dnodes, notifying waiters if no holds remain. 1129 */ 1130 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 1131 txh = list_next(&tx->tx_holds, txh)) { 1132 dnode_t *dn = txh->txh_dnode; 1133 1134 if (dn == NULL) 1135 continue; 1136 1137 mutex_enter(&dn->dn_mtx); 1138 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 1139 1140 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 1141 dn->dn_assigned_txg = 0; 1142 cv_broadcast(&dn->dn_notxholds); 1143 } 1144 mutex_exit(&dn->dn_mtx); 1145 } 1146 1147 if (tx->tx_tempreserve_cookie) 1148 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx); 1149 1150 if (!list_is_empty(&tx->tx_callbacks)) 1151 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks); 1152 1153 if (tx->tx_anyobj == FALSE) 1154 txg_rele_to_sync(&tx->tx_txgh); 1155 1156 dmu_tx_destroy(tx); 1157 } 1158 1159 void 1160 dmu_tx_abort(dmu_tx_t *tx) 1161 { 1162 ASSERT(tx->tx_txg == 0); 1163 1164 /* 1165 * Call any registered callbacks with an error code. 1166 */ 1167 if (!list_is_empty(&tx->tx_callbacks)) 1168 dmu_tx_do_callbacks(&tx->tx_callbacks, ECANCELED); 1169 1170 dmu_tx_destroy(tx); 1171 } 1172 1173 uint64_t 1174 dmu_tx_get_txg(dmu_tx_t *tx) 1175 { 1176 ASSERT(tx->tx_txg != 0); 1177 return (tx->tx_txg); 1178 } 1179 1180 dsl_pool_t * 1181 dmu_tx_pool(dmu_tx_t *tx) 1182 { 1183 ASSERT(tx->tx_pool != NULL); 1184 return (tx->tx_pool); 1185 } 1186 1187 void 1188 dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data) 1189 { 1190 dmu_tx_callback_t *dcb; 1191 1192 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_SLEEP); 1193 1194 dcb->dcb_func = func; 1195 dcb->dcb_data = data; 1196 1197 list_insert_tail(&tx->tx_callbacks, dcb); 1198 } 1199 1200 /* 1201 * Call all the commit callbacks on a list, with a given error code. 1202 */ 1203 void 1204 dmu_tx_do_callbacks(list_t *cb_list, int error) 1205 { 1206 dmu_tx_callback_t *dcb; 1207 1208 while ((dcb = list_head(cb_list)) != NULL) { 1209 list_remove(cb_list, dcb); 1210 dcb->dcb_func(dcb->dcb_data, error); 1211 kmem_free(dcb, sizeof (dmu_tx_callback_t)); 1212 } 1213 } 1214 1215 /* 1216 * Interface to hold a bunch of attributes. 1217 * used for creating new files. 1218 * attrsize is the total size of all attributes 1219 * to be added during object creation 1220 * 1221 * For updating/adding a single attribute dmu_tx_hold_sa() should be used. 1222 */ 1223 1224 /* 1225 * hold necessary attribute name for attribute registration. 1226 * should be a very rare case where this is needed. If it does 1227 * happen it would only happen on the first write to the file system. 1228 */ 1229 static void 1230 dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx) 1231 { 1232 if (!sa->sa_need_attr_registration) 1233 return; 1234 1235 for (int i = 0; i != sa->sa_num_attrs; i++) { 1236 if (!sa->sa_attr_table[i].sa_registered) { 1237 if (sa->sa_reg_attr_obj) 1238 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj, 1239 B_TRUE, sa->sa_attr_table[i].sa_name); 1240 else 1241 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 1242 B_TRUE, sa->sa_attr_table[i].sa_name); 1243 } 1244 } 1245 } 1246 1247 void 1248 dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object) 1249 { 1250 dmu_tx_hold_t *txh; 1251 1252 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, object, 1253 THT_SPILL, 0, 0); 1254 if (txh != NULL) 1255 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 1256 SPA_OLD_MAXBLOCKSIZE, FTAG); 1257 } 1258 1259 void 1260 dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize) 1261 { 1262 sa_os_t *sa = tx->tx_objset->os_sa; 1263 1264 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1265 1266 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1267 return; 1268 1269 if (tx->tx_objset->os_sa->sa_layout_attr_obj) { 1270 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1271 } else { 1272 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1273 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1274 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1275 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1276 } 1277 1278 dmu_tx_sa_registration_hold(sa, tx); 1279 1280 if (attrsize <= DN_OLD_MAX_BONUSLEN && !sa->sa_force_spill) 1281 return; 1282 1283 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT, 1284 THT_SPILL, 0, 0); 1285 } 1286 1287 /* 1288 * Hold SA attribute 1289 * 1290 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size) 1291 * 1292 * variable_size is the total size of all variable sized attributes 1293 * passed to this function. It is not the total size of all 1294 * variable size attributes that *may* exist on this object. 1295 */ 1296 void 1297 dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow) 1298 { 1299 uint64_t object; 1300 sa_os_t *sa = tx->tx_objset->os_sa; 1301 1302 ASSERT(hdl != NULL); 1303 1304 object = sa_handle_object(hdl); 1305 1306 dmu_tx_hold_bonus(tx, object); 1307 1308 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1309 return; 1310 1311 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 || 1312 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) { 1313 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1314 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1315 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1316 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1317 } 1318 1319 dmu_tx_sa_registration_hold(sa, tx); 1320 1321 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj) 1322 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1323 1324 if (sa->sa_force_spill || may_grow || hdl->sa_spill) { 1325 ASSERT(tx->tx_txg == 0); 1326 dmu_tx_hold_spill(tx, object); 1327 } else { 1328 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus; 1329 dnode_t *dn; 1330 1331 DB_DNODE_ENTER(db); 1332 dn = DB_DNODE(db); 1333 if (dn->dn_have_spill) { 1334 ASSERT(tx->tx_txg == 0); 1335 dmu_tx_hold_spill(tx, object); 1336 } 1337 DB_DNODE_EXIT(db); 1338 } 1339 } 1340