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 */ 26 27#include <sys/dmu.h> 28#include <sys/dmu_impl.h> 29#include <sys/dbuf.h> 30#include <sys/dmu_tx.h> 31#include <sys/dmu_objset.h> 32#include <sys/dsl_dataset.h> 33#include <sys/dsl_dir.h> 34#include <sys/dsl_pool.h> 35#include <sys/zap_impl.h> 36#include <sys/spa.h> 37#include <sys/sa.h> 38#include <sys/sa_impl.h> 39#include <sys/zfs_context.h> 40#include <sys/trace_zfs.h> 41 42typedef void (*dmu_tx_hold_func_t)(dmu_tx_t *tx, struct dnode *dn, 43 uint64_t arg1, uint64_t arg2); 44 45dmu_tx_stats_t dmu_tx_stats = { 46 { "dmu_tx_assigned", KSTAT_DATA_UINT64 }, 47 { "dmu_tx_delay", KSTAT_DATA_UINT64 }, 48 { "dmu_tx_error", KSTAT_DATA_UINT64 }, 49 { "dmu_tx_suspended", KSTAT_DATA_UINT64 }, 50 { "dmu_tx_group", KSTAT_DATA_UINT64 }, 51 { "dmu_tx_memory_reserve", KSTAT_DATA_UINT64 }, 52 { "dmu_tx_memory_reclaim", KSTAT_DATA_UINT64 }, 53 { "dmu_tx_dirty_throttle", KSTAT_DATA_UINT64 }, 54 { "dmu_tx_dirty_delay", KSTAT_DATA_UINT64 }, 55 { "dmu_tx_dirty_over_max", KSTAT_DATA_UINT64 }, 56 { "dmu_tx_dirty_frees_delay", KSTAT_DATA_UINT64 }, 57 { "dmu_tx_quota", KSTAT_DATA_UINT64 }, 58}; 59 60static kstat_t *dmu_tx_ksp; 61 62dmu_tx_t * 63dmu_tx_create_dd(dsl_dir_t *dd) 64{ 65 dmu_tx_t *tx = kmem_zalloc(sizeof (dmu_tx_t), KM_SLEEP); 66 tx->tx_dir = dd; 67 if (dd != NULL) 68 tx->tx_pool = dd->dd_pool; 69 list_create(&tx->tx_holds, sizeof (dmu_tx_hold_t), 70 offsetof(dmu_tx_hold_t, txh_node)); 71 list_create(&tx->tx_callbacks, sizeof (dmu_tx_callback_t), 72 offsetof(dmu_tx_callback_t, dcb_node)); 73 tx->tx_start = gethrtime(); 74 return (tx); 75} 76 77dmu_tx_t * 78dmu_tx_create(objset_t *os) 79{ 80 dmu_tx_t *tx = dmu_tx_create_dd(os->os_dsl_dataset->ds_dir); 81 tx->tx_objset = os; 82 return (tx); 83} 84 85dmu_tx_t * 86dmu_tx_create_assigned(struct dsl_pool *dp, uint64_t txg) 87{ 88 dmu_tx_t *tx = dmu_tx_create_dd(NULL); 89 90 TXG_VERIFY(dp->dp_spa, txg); 91 tx->tx_pool = dp; 92 tx->tx_txg = txg; 93 tx->tx_anyobj = TRUE; 94 95 return (tx); 96} 97 98int 99dmu_tx_is_syncing(dmu_tx_t *tx) 100{ 101 return (tx->tx_anyobj); 102} 103 104int 105dmu_tx_private_ok(dmu_tx_t *tx) 106{ 107 return (tx->tx_anyobj); 108} 109 110static dmu_tx_hold_t * 111dmu_tx_hold_dnode_impl(dmu_tx_t *tx, dnode_t *dn, enum dmu_tx_hold_type type, 112 uint64_t arg1, uint64_t arg2) 113{ 114 dmu_tx_hold_t *txh; 115 116 if (dn != NULL) { 117 (void) zfs_refcount_add(&dn->dn_holds, tx); 118 if (tx->tx_txg != 0) { 119 mutex_enter(&dn->dn_mtx); 120 /* 121 * dn->dn_assigned_txg == tx->tx_txg doesn't pose a 122 * problem, but there's no way for it to happen (for 123 * now, at least). 124 */ 125 ASSERT(dn->dn_assigned_txg == 0); 126 dn->dn_assigned_txg = tx->tx_txg; 127 (void) zfs_refcount_add(&dn->dn_tx_holds, tx); 128 mutex_exit(&dn->dn_mtx); 129 } 130 } 131 132 txh = kmem_zalloc(sizeof (dmu_tx_hold_t), KM_SLEEP); 133 txh->txh_tx = tx; 134 txh->txh_dnode = dn; 135 zfs_refcount_create(&txh->txh_space_towrite); 136 zfs_refcount_create(&txh->txh_memory_tohold); 137 txh->txh_type = type; 138 txh->txh_arg1 = arg1; 139 txh->txh_arg2 = arg2; 140 list_insert_tail(&tx->tx_holds, txh); 141 142 return (txh); 143} 144 145static dmu_tx_hold_t * 146dmu_tx_hold_object_impl(dmu_tx_t *tx, objset_t *os, uint64_t object, 147 enum dmu_tx_hold_type type, uint64_t arg1, uint64_t arg2) 148{ 149 dnode_t *dn = NULL; 150 dmu_tx_hold_t *txh; 151 int err; 152 153 if (object != DMU_NEW_OBJECT) { 154 err = dnode_hold(os, object, FTAG, &dn); 155 if (err != 0) { 156 tx->tx_err = err; 157 return (NULL); 158 } 159 } 160 txh = dmu_tx_hold_dnode_impl(tx, dn, type, arg1, arg2); 161 if (dn != NULL) 162 dnode_rele(dn, FTAG); 163 return (txh); 164} 165 166void 167dmu_tx_add_new_object(dmu_tx_t *tx, dnode_t *dn) 168{ 169 /* 170 * If we're syncing, they can manipulate any object anyhow, and 171 * the hold on the dnode_t can cause problems. 172 */ 173 if (!dmu_tx_is_syncing(tx)) 174 (void) dmu_tx_hold_dnode_impl(tx, dn, THT_NEWOBJECT, 0, 0); 175} 176 177/* 178 * This function reads specified data from disk. The specified data will 179 * be needed to perform the transaction -- i.e, it will be read after 180 * we do dmu_tx_assign(). There are two reasons that we read the data now 181 * (before dmu_tx_assign()): 182 * 183 * 1. Reading it now has potentially better performance. The transaction 184 * has not yet been assigned, so the TXG is not held open, and also the 185 * caller typically has less locks held when calling dmu_tx_hold_*() than 186 * after the transaction has been assigned. This reduces the lock (and txg) 187 * hold times, thus reducing lock contention. 188 * 189 * 2. It is easier for callers (primarily the ZPL) to handle i/o errors 190 * that are detected before they start making changes to the DMU state 191 * (i.e. now). Once the transaction has been assigned, and some DMU 192 * state has been changed, it can be difficult to recover from an i/o 193 * error (e.g. to undo the changes already made in memory at the DMU 194 * layer). Typically code to do so does not exist in the caller -- it 195 * assumes that the data has already been cached and thus i/o errors are 196 * not possible. 197 * 198 * It has been observed that the i/o initiated here can be a performance 199 * problem, and it appears to be optional, because we don't look at the 200 * data which is read. However, removing this read would only serve to 201 * move the work elsewhere (after the dmu_tx_assign()), where it may 202 * have a greater impact on performance (in addition to the impact on 203 * fault tolerance noted above). 204 */ 205static int 206dmu_tx_check_ioerr(zio_t *zio, dnode_t *dn, int level, uint64_t blkid) 207{ 208 int err; 209 dmu_buf_impl_t *db; 210 211 rw_enter(&dn->dn_struct_rwlock, RW_READER); 212 db = dbuf_hold_level(dn, level, blkid, FTAG); 213 rw_exit(&dn->dn_struct_rwlock); 214 if (db == NULL) 215 return (SET_ERROR(EIO)); 216 err = dbuf_read(db, zio, DB_RF_CANFAIL | DB_RF_NOPREFETCH); 217 dbuf_rele(db, FTAG); 218 return (err); 219} 220 221/* ARGSUSED */ 222static void 223dmu_tx_count_write(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 224{ 225 dnode_t *dn = txh->txh_dnode; 226 int err = 0; 227 228 if (len == 0) 229 return; 230 231 (void) zfs_refcount_add_many(&txh->txh_space_towrite, len, FTAG); 232 233 if (dn == NULL) 234 return; 235 236 /* 237 * For i/o error checking, read the blocks that will be needed 238 * to perform the write: the first and last level-0 blocks (if 239 * they are not aligned, i.e. if they are partial-block writes), 240 * and all the level-1 blocks. 241 */ 242 if (dn->dn_maxblkid == 0) { 243 if (off < dn->dn_datablksz && 244 (off > 0 || len < dn->dn_datablksz)) { 245 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 246 if (err != 0) { 247 txh->txh_tx->tx_err = err; 248 } 249 } 250 } else { 251 zio_t *zio = zio_root(dn->dn_objset->os_spa, 252 NULL, NULL, ZIO_FLAG_CANFAIL); 253 254 /* first level-0 block */ 255 uint64_t start = off >> dn->dn_datablkshift; 256 if (P2PHASE(off, dn->dn_datablksz) || len < dn->dn_datablksz) { 257 err = dmu_tx_check_ioerr(zio, dn, 0, start); 258 if (err != 0) { 259 txh->txh_tx->tx_err = err; 260 } 261 } 262 263 /* last level-0 block */ 264 uint64_t end = (off + len - 1) >> dn->dn_datablkshift; 265 if (end != start && end <= dn->dn_maxblkid && 266 P2PHASE(off + len, dn->dn_datablksz)) { 267 err = dmu_tx_check_ioerr(zio, dn, 0, end); 268 if (err != 0) { 269 txh->txh_tx->tx_err = err; 270 } 271 } 272 273 /* level-1 blocks */ 274 if (dn->dn_nlevels > 1) { 275 int shft = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 276 for (uint64_t i = (start >> shft) + 1; 277 i < end >> shft; i++) { 278 err = dmu_tx_check_ioerr(zio, dn, 1, i); 279 if (err != 0) { 280 txh->txh_tx->tx_err = err; 281 } 282 } 283 } 284 285 err = zio_wait(zio); 286 if (err != 0) { 287 txh->txh_tx->tx_err = err; 288 } 289 } 290} 291 292static void 293dmu_tx_count_dnode(dmu_tx_hold_t *txh) 294{ 295 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 296 DNODE_MIN_SIZE, FTAG); 297} 298 299void 300dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len) 301{ 302 dmu_tx_hold_t *txh; 303 304 ASSERT0(tx->tx_txg); 305 ASSERT3U(len, <=, DMU_MAX_ACCESS); 306 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 307 308 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 309 object, THT_WRITE, off, len); 310 if (txh != NULL) { 311 dmu_tx_count_write(txh, off, len); 312 dmu_tx_count_dnode(txh); 313 } 314} 315 316void 317dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len) 318{ 319 dmu_tx_hold_t *txh; 320 321 ASSERT0(tx->tx_txg); 322 ASSERT3U(len, <=, DMU_MAX_ACCESS); 323 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 324 325 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_WRITE, off, len); 326 if (txh != NULL) { 327 dmu_tx_count_write(txh, off, len); 328 dmu_tx_count_dnode(txh); 329 } 330} 331 332/* 333 * This function marks the transaction as being a "net free". The end 334 * result is that refquotas will be disabled for this transaction, and 335 * this transaction will be able to use half of the pool space overhead 336 * (see dsl_pool_adjustedsize()). Therefore this function should only 337 * be called for transactions that we expect will not cause a net increase 338 * in the amount of space used (but it's OK if that is occasionally not true). 339 */ 340void 341dmu_tx_mark_netfree(dmu_tx_t *tx) 342{ 343 tx->tx_netfree = B_TRUE; 344} 345 346static void 347dmu_tx_hold_free_impl(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 348{ 349 dmu_tx_t *tx = txh->txh_tx; 350 dnode_t *dn = txh->txh_dnode; 351 int err; 352 353 ASSERT(tx->tx_txg == 0); 354 355 dmu_tx_count_dnode(txh); 356 357 if (off >= (dn->dn_maxblkid + 1) * dn->dn_datablksz) 358 return; 359 if (len == DMU_OBJECT_END) 360 len = (dn->dn_maxblkid + 1) * dn->dn_datablksz - off; 361 362 dmu_tx_count_dnode(txh); 363 364 /* 365 * For i/o error checking, we read the first and last level-0 366 * blocks if they are not aligned, and all the level-1 blocks. 367 * 368 * Note: dbuf_free_range() assumes that we have not instantiated 369 * any level-0 dbufs that will be completely freed. Therefore we must 370 * exercise care to not read or count the first and last blocks 371 * if they are blocksize-aligned. 372 */ 373 if (dn->dn_datablkshift == 0) { 374 if (off != 0 || len < dn->dn_datablksz) 375 dmu_tx_count_write(txh, 0, dn->dn_datablksz); 376 } else { 377 /* first block will be modified if it is not aligned */ 378 if (!IS_P2ALIGNED(off, 1 << dn->dn_datablkshift)) 379 dmu_tx_count_write(txh, off, 1); 380 /* last block will be modified if it is not aligned */ 381 if (!IS_P2ALIGNED(off + len, 1 << dn->dn_datablkshift)) 382 dmu_tx_count_write(txh, off + len, 1); 383 } 384 385 /* 386 * Check level-1 blocks. 387 */ 388 if (dn->dn_nlevels > 1) { 389 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 390 SPA_BLKPTRSHIFT; 391 uint64_t start = off >> shift; 392 uint64_t end = (off + len) >> shift; 393 394 ASSERT(dn->dn_indblkshift != 0); 395 396 /* 397 * dnode_reallocate() can result in an object with indirect 398 * blocks having an odd data block size. In this case, 399 * just check the single block. 400 */ 401 if (dn->dn_datablkshift == 0) 402 start = end = 0; 403 404 zio_t *zio = zio_root(tx->tx_pool->dp_spa, 405 NULL, NULL, ZIO_FLAG_CANFAIL); 406 for (uint64_t i = start; i <= end; i++) { 407 uint64_t ibyte = i << shift; 408 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0); 409 i = ibyte >> shift; 410 if (err == ESRCH || i > end) 411 break; 412 if (err != 0) { 413 tx->tx_err = err; 414 (void) zio_wait(zio); 415 return; 416 } 417 418 (void) zfs_refcount_add_many(&txh->txh_memory_tohold, 419 1 << dn->dn_indblkshift, FTAG); 420 421 err = dmu_tx_check_ioerr(zio, dn, 1, i); 422 if (err != 0) { 423 tx->tx_err = err; 424 (void) zio_wait(zio); 425 return; 426 } 427 } 428 err = zio_wait(zio); 429 if (err != 0) { 430 tx->tx_err = err; 431 return; 432 } 433 } 434} 435 436void 437dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len) 438{ 439 dmu_tx_hold_t *txh; 440 441 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 442 object, THT_FREE, off, len); 443 if (txh != NULL) 444 (void) dmu_tx_hold_free_impl(txh, off, len); 445} 446 447void 448dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, uint64_t len) 449{ 450 dmu_tx_hold_t *txh; 451 452 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_FREE, off, len); 453 if (txh != NULL) 454 (void) dmu_tx_hold_free_impl(txh, off, len); 455} 456 457static void 458dmu_tx_hold_zap_impl(dmu_tx_hold_t *txh, const char *name) 459{ 460 dmu_tx_t *tx = txh->txh_tx; 461 dnode_t *dn = txh->txh_dnode; 462 int err; 463 464 ASSERT(tx->tx_txg == 0); 465 466 dmu_tx_count_dnode(txh); 467 468 /* 469 * Modifying a almost-full microzap is around the worst case (128KB) 470 * 471 * If it is a fat zap, the worst case would be 7*16KB=112KB: 472 * - 3 blocks overwritten: target leaf, ptrtbl block, header block 473 * - 4 new blocks written if adding: 474 * - 2 blocks for possibly split leaves, 475 * - 2 grown ptrtbl blocks 476 */ 477 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 478 MZAP_MAX_BLKSZ, FTAG); 479 480 if (dn == NULL) 481 return; 482 483 ASSERT3U(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP); 484 485 if (dn->dn_maxblkid == 0 || name == NULL) { 486 /* 487 * This is a microzap (only one block), or we don't know 488 * the name. Check the first block for i/o errors. 489 */ 490 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 491 if (err != 0) { 492 tx->tx_err = err; 493 } 494 } else { 495 /* 496 * Access the name so that we'll check for i/o errors to 497 * the leaf blocks, etc. We ignore ENOENT, as this name 498 * may not yet exist. 499 */ 500 err = zap_lookup_by_dnode(dn, name, 8, 0, NULL); 501 if (err == EIO || err == ECKSUM || err == ENXIO) { 502 tx->tx_err = err; 503 } 504 } 505} 506 507void 508dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name) 509{ 510 dmu_tx_hold_t *txh; 511 512 ASSERT0(tx->tx_txg); 513 514 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 515 object, THT_ZAP, add, (uintptr_t)name); 516 if (txh != NULL) 517 dmu_tx_hold_zap_impl(txh, name); 518} 519 520void 521dmu_tx_hold_zap_by_dnode(dmu_tx_t *tx, dnode_t *dn, int add, const char *name) 522{ 523 dmu_tx_hold_t *txh; 524 525 ASSERT0(tx->tx_txg); 526 ASSERT(dn != NULL); 527 528 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_ZAP, add, (uintptr_t)name); 529 if (txh != NULL) 530 dmu_tx_hold_zap_impl(txh, name); 531} 532 533void 534dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object) 535{ 536 dmu_tx_hold_t *txh; 537 538 ASSERT(tx->tx_txg == 0); 539 540 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 541 object, THT_BONUS, 0, 0); 542 if (txh) 543 dmu_tx_count_dnode(txh); 544} 545 546void 547dmu_tx_hold_bonus_by_dnode(dmu_tx_t *tx, dnode_t *dn) 548{ 549 dmu_tx_hold_t *txh; 550 551 ASSERT0(tx->tx_txg); 552 553 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_BONUS, 0, 0); 554 if (txh) 555 dmu_tx_count_dnode(txh); 556} 557 558void 559dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space) 560{ 561 dmu_tx_hold_t *txh; 562 563 ASSERT(tx->tx_txg == 0); 564 565 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 566 DMU_NEW_OBJECT, THT_SPACE, space, 0); 567 if (txh) { 568 (void) zfs_refcount_add_many( 569 &txh->txh_space_towrite, space, FTAG); 570 } 571} 572 573#ifdef ZFS_DEBUG 574void 575dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db) 576{ 577 boolean_t match_object = B_FALSE; 578 boolean_t match_offset = B_FALSE; 579 580 DB_DNODE_ENTER(db); 581 dnode_t *dn = DB_DNODE(db); 582 ASSERT(tx->tx_txg != 0); 583 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset); 584 ASSERT3U(dn->dn_object, ==, db->db.db_object); 585 586 if (tx->tx_anyobj) { 587 DB_DNODE_EXIT(db); 588 return; 589 } 590 591 /* XXX No checking on the meta dnode for now */ 592 if (db->db.db_object == DMU_META_DNODE_OBJECT) { 593 DB_DNODE_EXIT(db); 594 return; 595 } 596 597 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 598 txh = list_next(&tx->tx_holds, txh)) { 599 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 600 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT) 601 match_object = TRUE; 602 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) { 603 int datablkshift = dn->dn_datablkshift ? 604 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT; 605 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 606 int shift = datablkshift + epbs * db->db_level; 607 uint64_t beginblk = shift >= 64 ? 0 : 608 (txh->txh_arg1 >> shift); 609 uint64_t endblk = shift >= 64 ? 0 : 610 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift); 611 uint64_t blkid = db->db_blkid; 612 613 /* XXX txh_arg2 better not be zero... */ 614 615 dprintf("found txh type %x beginblk=%llx endblk=%llx\n", 616 txh->txh_type, beginblk, endblk); 617 618 switch (txh->txh_type) { 619 case THT_WRITE: 620 if (blkid >= beginblk && blkid <= endblk) 621 match_offset = TRUE; 622 /* 623 * We will let this hold work for the bonus 624 * or spill buffer so that we don't need to 625 * hold it when creating a new object. 626 */ 627 if (blkid == DMU_BONUS_BLKID || 628 blkid == DMU_SPILL_BLKID) 629 match_offset = TRUE; 630 /* 631 * They might have to increase nlevels, 632 * thus dirtying the new TLIBs. Or the 633 * might have to change the block size, 634 * thus dirying the new lvl=0 blk=0. 635 */ 636 if (blkid == 0) 637 match_offset = TRUE; 638 break; 639 case THT_FREE: 640 /* 641 * We will dirty all the level 1 blocks in 642 * the free range and perhaps the first and 643 * last level 0 block. 644 */ 645 if (blkid >= beginblk && (blkid <= endblk || 646 txh->txh_arg2 == DMU_OBJECT_END)) 647 match_offset = TRUE; 648 break; 649 case THT_SPILL: 650 if (blkid == DMU_SPILL_BLKID) 651 match_offset = TRUE; 652 break; 653 case THT_BONUS: 654 if (blkid == DMU_BONUS_BLKID) 655 match_offset = TRUE; 656 break; 657 case THT_ZAP: 658 match_offset = TRUE; 659 break; 660 case THT_NEWOBJECT: 661 match_object = TRUE; 662 break; 663 default: 664 cmn_err(CE_PANIC, "bad txh_type %d", 665 txh->txh_type); 666 } 667 } 668 if (match_object && match_offset) { 669 DB_DNODE_EXIT(db); 670 return; 671 } 672 } 673 DB_DNODE_EXIT(db); 674 panic("dirtying dbuf obj=%llx lvl=%u blkid=%llx but not tx_held\n", 675 (u_longlong_t)db->db.db_object, db->db_level, 676 (u_longlong_t)db->db_blkid); 677} 678#endif 679 680/* 681 * If we can't do 10 iops, something is wrong. Let us go ahead 682 * and hit zfs_dirty_data_max. 683 */ 684hrtime_t zfs_delay_max_ns = 100 * MICROSEC; /* 100 milliseconds */ 685int zfs_delay_resolution_ns = 100 * 1000; /* 100 microseconds */ 686 687/* 688 * We delay transactions when we've determined that the backend storage 689 * isn't able to accommodate the rate of incoming writes. 690 * 691 * If there is already a transaction waiting, we delay relative to when 692 * that transaction finishes waiting. This way the calculated min_time 693 * is independent of the number of threads concurrently executing 694 * transactions. 695 * 696 * If we are the only waiter, wait relative to when the transaction 697 * started, rather than the current time. This credits the transaction for 698 * "time already served", e.g. reading indirect blocks. 699 * 700 * The minimum time for a transaction to take is calculated as: 701 * min_time = scale * (dirty - min) / (max - dirty) 702 * min_time is then capped at zfs_delay_max_ns. 703 * 704 * The delay has two degrees of freedom that can be adjusted via tunables. 705 * The percentage of dirty data at which we start to delay is defined by 706 * zfs_delay_min_dirty_percent. This should typically be at or above 707 * zfs_vdev_async_write_active_max_dirty_percent so that we only start to 708 * delay after writing at full speed has failed to keep up with the incoming 709 * write rate. The scale of the curve is defined by zfs_delay_scale. Roughly 710 * speaking, this variable determines the amount of delay at the midpoint of 711 * the curve. 712 * 713 * delay 714 * 10ms +-------------------------------------------------------------*+ 715 * | *| 716 * 9ms + *+ 717 * | *| 718 * 8ms + *+ 719 * | * | 720 * 7ms + * + 721 * | * | 722 * 6ms + * + 723 * | * | 724 * 5ms + * + 725 * | * | 726 * 4ms + * + 727 * | * | 728 * 3ms + * + 729 * | * | 730 * 2ms + (midpoint) * + 731 * | | ** | 732 * 1ms + v *** + 733 * | zfs_delay_scale ----------> ******** | 734 * 0 +-------------------------------------*********----------------+ 735 * 0% <- zfs_dirty_data_max -> 100% 736 * 737 * Note that since the delay is added to the outstanding time remaining on the 738 * most recent transaction, the delay is effectively the inverse of IOPS. 739 * Here the midpoint of 500us translates to 2000 IOPS. The shape of the curve 740 * was chosen such that small changes in the amount of accumulated dirty data 741 * in the first 3/4 of the curve yield relatively small differences in the 742 * amount of delay. 743 * 744 * The effects can be easier to understand when the amount of delay is 745 * represented on a log scale: 746 * 747 * delay 748 * 100ms +-------------------------------------------------------------++ 749 * + + 750 * | | 751 * + *+ 752 * 10ms + *+ 753 * + ** + 754 * | (midpoint) ** | 755 * + | ** + 756 * 1ms + v **** + 757 * + zfs_delay_scale ----------> ***** + 758 * | **** | 759 * + **** + 760 * 100us + ** + 761 * + * + 762 * | * | 763 * + * + 764 * 10us + * + 765 * + + 766 * | | 767 * + + 768 * +--------------------------------------------------------------+ 769 * 0% <- zfs_dirty_data_max -> 100% 770 * 771 * Note here that only as the amount of dirty data approaches its limit does 772 * the delay start to increase rapidly. The goal of a properly tuned system 773 * should be to keep the amount of dirty data out of that range by first 774 * ensuring that the appropriate limits are set for the I/O scheduler to reach 775 * optimal throughput on the backend storage, and then by changing the value 776 * of zfs_delay_scale to increase the steepness of the curve. 777 */ 778static void 779dmu_tx_delay(dmu_tx_t *tx, uint64_t dirty) 780{ 781 dsl_pool_t *dp = tx->tx_pool; 782 uint64_t delay_min_bytes = 783 zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; 784 hrtime_t wakeup, min_tx_time, now; 785 786 if (dirty <= delay_min_bytes) 787 return; 788 789 /* 790 * The caller has already waited until we are under the max. 791 * We make them pass us the amount of dirty data so we don't 792 * have to handle the case of it being >= the max, which could 793 * cause a divide-by-zero if it's == the max. 794 */ 795 ASSERT3U(dirty, <, zfs_dirty_data_max); 796 797 now = gethrtime(); 798 min_tx_time = zfs_delay_scale * 799 (dirty - delay_min_bytes) / (zfs_dirty_data_max - dirty); 800 min_tx_time = MIN(min_tx_time, zfs_delay_max_ns); 801 if (now > tx->tx_start + min_tx_time) 802 return; 803 804 DTRACE_PROBE3(delay__mintime, dmu_tx_t *, tx, uint64_t, dirty, 805 uint64_t, min_tx_time); 806 807 mutex_enter(&dp->dp_lock); 808 wakeup = MAX(tx->tx_start + min_tx_time, 809 dp->dp_last_wakeup + min_tx_time); 810 dp->dp_last_wakeup = wakeup; 811 mutex_exit(&dp->dp_lock); 812 813 zfs_sleep_until(wakeup); 814} 815 816/* 817 * This routine attempts to assign the transaction to a transaction group. 818 * To do so, we must determine if there is sufficient free space on disk. 819 * 820 * If this is a "netfree" transaction (i.e. we called dmu_tx_mark_netfree() 821 * on it), then it is assumed that there is sufficient free space, 822 * unless there's insufficient slop space in the pool (see the comment 823 * above spa_slop_shift in spa_misc.c). 824 * 825 * If it is not a "netfree" transaction, then if the data already on disk 826 * is over the allowed usage (e.g. quota), this will fail with EDQUOT or 827 * ENOSPC. Otherwise, if the current rough estimate of pending changes, 828 * plus the rough estimate of this transaction's changes, may exceed the 829 * allowed usage, then this will fail with ERESTART, which will cause the 830 * caller to wait for the pending changes to be written to disk (by waiting 831 * for the next TXG to open), and then check the space usage again. 832 * 833 * The rough estimate of pending changes is comprised of the sum of: 834 * 835 * - this transaction's holds' txh_space_towrite 836 * 837 * - dd_tempreserved[], which is the sum of in-flight transactions' 838 * holds' txh_space_towrite (i.e. those transactions that have called 839 * dmu_tx_assign() but not yet called dmu_tx_commit()). 840 * 841 * - dd_space_towrite[], which is the amount of dirtied dbufs. 842 * 843 * Note that all of these values are inflated by spa_get_worst_case_asize(), 844 * which means that we may get ERESTART well before we are actually in danger 845 * of running out of space, but this also mitigates any small inaccuracies 846 * in the rough estimate (e.g. txh_space_towrite doesn't take into account 847 * indirect blocks, and dd_space_towrite[] doesn't take into account changes 848 * to the MOS). 849 * 850 * Note that due to this algorithm, it is possible to exceed the allowed 851 * usage by one transaction. Also, as we approach the allowed usage, 852 * we will allow a very limited amount of changes into each TXG, thus 853 * decreasing performance. 854 */ 855static int 856dmu_tx_try_assign(dmu_tx_t *tx, uint64_t txg_how) 857{ 858 spa_t *spa = tx->tx_pool->dp_spa; 859 860 ASSERT0(tx->tx_txg); 861 862 if (tx->tx_err) { 863 DMU_TX_STAT_BUMP(dmu_tx_error); 864 return (tx->tx_err); 865 } 866 867 if (spa_suspended(spa)) { 868 DMU_TX_STAT_BUMP(dmu_tx_suspended); 869 870 /* 871 * If the user has indicated a blocking failure mode 872 * then return ERESTART which will block in dmu_tx_wait(). 873 * Otherwise, return EIO so that an error can get 874 * propagated back to the VOP calls. 875 * 876 * Note that we always honor the txg_how flag regardless 877 * of the failuremode setting. 878 */ 879 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE && 880 !(txg_how & TXG_WAIT)) 881 return (SET_ERROR(EIO)); 882 883 return (SET_ERROR(ERESTART)); 884 } 885 886 if (!tx->tx_dirty_delayed && 887 dsl_pool_need_dirty_delay(tx->tx_pool)) { 888 tx->tx_wait_dirty = B_TRUE; 889 DMU_TX_STAT_BUMP(dmu_tx_dirty_delay); 890 return (SET_ERROR(ERESTART)); 891 } 892 893 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh); 894 tx->tx_needassign_txh = NULL; 895 896 /* 897 * NB: No error returns are allowed after txg_hold_open, but 898 * before processing the dnode holds, due to the 899 * dmu_tx_unassign() logic. 900 */ 901 902 uint64_t towrite = 0; 903 uint64_t tohold = 0; 904 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 905 txh = list_next(&tx->tx_holds, txh)) { 906 dnode_t *dn = txh->txh_dnode; 907 if (dn != NULL) { 908 /* 909 * This thread can't hold the dn_struct_rwlock 910 * while assigning the tx, because this can lead to 911 * deadlock. Specifically, if this dnode is already 912 * assigned to an earlier txg, this thread may need 913 * to wait for that txg to sync (the ERESTART case 914 * below). The other thread that has assigned this 915 * dnode to an earlier txg prevents this txg from 916 * syncing until its tx can complete (calling 917 * dmu_tx_commit()), but it may need to acquire the 918 * dn_struct_rwlock to do so (e.g. via 919 * dmu_buf_hold*()). 920 * 921 * Note that this thread can't hold the lock for 922 * read either, but the rwlock doesn't record 923 * enough information to make that assertion. 924 */ 925 ASSERT(!RW_WRITE_HELD(&dn->dn_struct_rwlock)); 926 927 mutex_enter(&dn->dn_mtx); 928 if (dn->dn_assigned_txg == tx->tx_txg - 1) { 929 mutex_exit(&dn->dn_mtx); 930 tx->tx_needassign_txh = txh; 931 DMU_TX_STAT_BUMP(dmu_tx_group); 932 return (SET_ERROR(ERESTART)); 933 } 934 if (dn->dn_assigned_txg == 0) 935 dn->dn_assigned_txg = tx->tx_txg; 936 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 937 (void) zfs_refcount_add(&dn->dn_tx_holds, tx); 938 mutex_exit(&dn->dn_mtx); 939 } 940 towrite += zfs_refcount_count(&txh->txh_space_towrite); 941 tohold += zfs_refcount_count(&txh->txh_memory_tohold); 942 } 943 944 /* needed allocation: worst-case estimate of write space */ 945 uint64_t asize = spa_get_worst_case_asize(tx->tx_pool->dp_spa, towrite); 946 /* calculate memory footprint estimate */ 947 uint64_t memory = towrite + tohold; 948 949 if (tx->tx_dir != NULL && asize != 0) { 950 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory, 951 asize, tx->tx_netfree, &tx->tx_tempreserve_cookie, tx); 952 if (err != 0) 953 return (err); 954 } 955 956 DMU_TX_STAT_BUMP(dmu_tx_assigned); 957 958 return (0); 959} 960 961static void 962dmu_tx_unassign(dmu_tx_t *tx) 963{ 964 if (tx->tx_txg == 0) 965 return; 966 967 txg_rele_to_quiesce(&tx->tx_txgh); 968 969 /* 970 * Walk the transaction's hold list, removing the hold on the 971 * associated dnode, and notifying waiters if the refcount drops to 0. 972 */ 973 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); 974 txh && txh != tx->tx_needassign_txh; 975 txh = list_next(&tx->tx_holds, txh)) { 976 dnode_t *dn = txh->txh_dnode; 977 978 if (dn == NULL) 979 continue; 980 mutex_enter(&dn->dn_mtx); 981 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 982 983 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 984 dn->dn_assigned_txg = 0; 985 cv_broadcast(&dn->dn_notxholds); 986 } 987 mutex_exit(&dn->dn_mtx); 988 } 989 990 txg_rele_to_sync(&tx->tx_txgh); 991 992 tx->tx_lasttried_txg = tx->tx_txg; 993 tx->tx_txg = 0; 994} 995 996/* 997 * Assign tx to a transaction group; txg_how is a bitmask: 998 * 999 * If TXG_WAIT is set and the currently open txg is full, this function 1000 * will wait until there's a new txg. This should be used when no locks 1001 * are being held. With this bit set, this function will only fail if 1002 * we're truly out of space (or over quota). 1003 * 1004 * If TXG_WAIT is *not* set and we can't assign into the currently open 1005 * txg without blocking, this function will return immediately with 1006 * ERESTART. This should be used whenever locks are being held. On an 1007 * ERESTART error, the caller should drop all locks, call dmu_tx_wait(), 1008 * and try again. 1009 * 1010 * If TXG_NOTHROTTLE is set, this indicates that this tx should not be 1011 * delayed due on the ZFS Write Throttle (see comments in dsl_pool.c for 1012 * details on the throttle). This is used by the VFS operations, after 1013 * they have already called dmu_tx_wait() (though most likely on a 1014 * different tx). 1015 * 1016 * It is guaranteed that subsequent successful calls to dmu_tx_assign() 1017 * will assign the tx to monotonically increasing txgs. Of course this is 1018 * not strong monotonicity, because the same txg can be returned multiple 1019 * times in a row. This guarantee holds both for subsequent calls from 1020 * one thread and for multiple threads. For example, it is impossible to 1021 * observe the following sequence of events: 1022 * 1023 * Thread 1 Thread 2 1024 * 1025 * dmu_tx_assign(T1, ...) 1026 * 1 <- dmu_tx_get_txg(T1) 1027 * dmu_tx_assign(T2, ...) 1028 * 2 <- dmu_tx_get_txg(T2) 1029 * dmu_tx_assign(T3, ...) 1030 * 1 <- dmu_tx_get_txg(T3) 1031 */ 1032int 1033dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how) 1034{ 1035 int err; 1036 1037 ASSERT(tx->tx_txg == 0); 1038 ASSERT0(txg_how & ~(TXG_WAIT | TXG_NOTHROTTLE)); 1039 ASSERT(!dsl_pool_sync_context(tx->tx_pool)); 1040 1041 /* If we might wait, we must not hold the config lock. */ 1042 IMPLY((txg_how & TXG_WAIT), !dsl_pool_config_held(tx->tx_pool)); 1043 1044 if ((txg_how & TXG_NOTHROTTLE)) 1045 tx->tx_dirty_delayed = B_TRUE; 1046 1047 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) { 1048 dmu_tx_unassign(tx); 1049 1050 if (err != ERESTART || !(txg_how & TXG_WAIT)) 1051 return (err); 1052 1053 dmu_tx_wait(tx); 1054 } 1055 1056 txg_rele_to_quiesce(&tx->tx_txgh); 1057 1058 return (0); 1059} 1060 1061void 1062dmu_tx_wait(dmu_tx_t *tx) 1063{ 1064 spa_t *spa = tx->tx_pool->dp_spa; 1065 dsl_pool_t *dp = tx->tx_pool; 1066 hrtime_t before; 1067 1068 ASSERT(tx->tx_txg == 0); 1069 ASSERT(!dsl_pool_config_held(tx->tx_pool)); 1070 1071 before = gethrtime(); 1072 1073 if (tx->tx_wait_dirty) { 1074 uint64_t dirty; 1075 1076 /* 1077 * dmu_tx_try_assign() has determined that we need to wait 1078 * because we've consumed much or all of the dirty buffer 1079 * space. 1080 */ 1081 mutex_enter(&dp->dp_lock); 1082 if (dp->dp_dirty_total >= zfs_dirty_data_max) 1083 DMU_TX_STAT_BUMP(dmu_tx_dirty_over_max); 1084 while (dp->dp_dirty_total >= zfs_dirty_data_max) 1085 cv_wait(&dp->dp_spaceavail_cv, &dp->dp_lock); 1086 dirty = dp->dp_dirty_total; 1087 mutex_exit(&dp->dp_lock); 1088 1089 dmu_tx_delay(tx, dirty); 1090 1091 tx->tx_wait_dirty = B_FALSE; 1092 1093 /* 1094 * Note: setting tx_dirty_delayed only has effect if the 1095 * caller used TX_WAIT. Otherwise they are going to 1096 * destroy this tx and try again. The common case, 1097 * zfs_write(), uses TX_WAIT. 1098 */ 1099 tx->tx_dirty_delayed = B_TRUE; 1100 } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { 1101 /* 1102 * If the pool is suspended we need to wait until it 1103 * is resumed. Note that it's possible that the pool 1104 * has become active after this thread has tried to 1105 * obtain a tx. If that's the case then tx_lasttried_txg 1106 * would not have been set. 1107 */ 1108 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1109 } else if (tx->tx_needassign_txh) { 1110 dnode_t *dn = tx->tx_needassign_txh->txh_dnode; 1111 1112 mutex_enter(&dn->dn_mtx); 1113 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1) 1114 cv_wait(&dn->dn_notxholds, &dn->dn_mtx); 1115 mutex_exit(&dn->dn_mtx); 1116 tx->tx_needassign_txh = NULL; 1117 } else { 1118 /* 1119 * If we have a lot of dirty data just wait until we sync 1120 * out a TXG at which point we'll hopefully have synced 1121 * a portion of the changes. 1122 */ 1123 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1124 } 1125 1126 spa_tx_assign_add_nsecs(spa, gethrtime() - before); 1127} 1128 1129static void 1130dmu_tx_destroy(dmu_tx_t *tx) 1131{ 1132 dmu_tx_hold_t *txh; 1133 1134 while ((txh = list_head(&tx->tx_holds)) != NULL) { 1135 dnode_t *dn = txh->txh_dnode; 1136 1137 list_remove(&tx->tx_holds, txh); 1138 zfs_refcount_destroy_many(&txh->txh_space_towrite, 1139 zfs_refcount_count(&txh->txh_space_towrite)); 1140 zfs_refcount_destroy_many(&txh->txh_memory_tohold, 1141 zfs_refcount_count(&txh->txh_memory_tohold)); 1142 kmem_free(txh, sizeof (dmu_tx_hold_t)); 1143 if (dn != NULL) 1144 dnode_rele(dn, tx); 1145 } 1146 1147 list_destroy(&tx->tx_callbacks); 1148 list_destroy(&tx->tx_holds); 1149 kmem_free(tx, sizeof (dmu_tx_t)); 1150} 1151 1152void 1153dmu_tx_commit(dmu_tx_t *tx) 1154{ 1155 ASSERT(tx->tx_txg != 0); 1156 1157 /* 1158 * Go through the transaction's hold list and remove holds on 1159 * associated dnodes, notifying waiters if no holds remain. 1160 */ 1161 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 1162 txh = list_next(&tx->tx_holds, txh)) { 1163 dnode_t *dn = txh->txh_dnode; 1164 1165 if (dn == NULL) 1166 continue; 1167 1168 mutex_enter(&dn->dn_mtx); 1169 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 1170 1171 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 1172 dn->dn_assigned_txg = 0; 1173 cv_broadcast(&dn->dn_notxholds); 1174 } 1175 mutex_exit(&dn->dn_mtx); 1176 } 1177 1178 if (tx->tx_tempreserve_cookie) 1179 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx); 1180 1181 if (!list_is_empty(&tx->tx_callbacks)) 1182 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks); 1183 1184 if (tx->tx_anyobj == FALSE) 1185 txg_rele_to_sync(&tx->tx_txgh); 1186 1187 dmu_tx_destroy(tx); 1188} 1189 1190void 1191dmu_tx_abort(dmu_tx_t *tx) 1192{ 1193 ASSERT(tx->tx_txg == 0); 1194 1195 /* 1196 * Call any registered callbacks with an error code. 1197 */ 1198 if (!list_is_empty(&tx->tx_callbacks)) 1199 dmu_tx_do_callbacks(&tx->tx_callbacks, SET_ERROR(ECANCELED)); 1200 1201 dmu_tx_destroy(tx); 1202} 1203 1204uint64_t 1205dmu_tx_get_txg(dmu_tx_t *tx) 1206{ 1207 ASSERT(tx->tx_txg != 0); 1208 return (tx->tx_txg); 1209} 1210 1211dsl_pool_t * 1212dmu_tx_pool(dmu_tx_t *tx) 1213{ 1214 ASSERT(tx->tx_pool != NULL); 1215 return (tx->tx_pool); 1216} 1217 1218void 1219dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data) 1220{ 1221 dmu_tx_callback_t *dcb; 1222 1223 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_SLEEP); 1224 1225 dcb->dcb_func = func; 1226 dcb->dcb_data = data; 1227 1228 list_insert_tail(&tx->tx_callbacks, dcb); 1229} 1230 1231/* 1232 * Call all the commit callbacks on a list, with a given error code. 1233 */ 1234void 1235dmu_tx_do_callbacks(list_t *cb_list, int error) 1236{ 1237 dmu_tx_callback_t *dcb; 1238 1239 while ((dcb = list_tail(cb_list)) != NULL) { 1240 list_remove(cb_list, dcb); 1241 dcb->dcb_func(dcb->dcb_data, error); 1242 kmem_free(dcb, sizeof (dmu_tx_callback_t)); 1243 } 1244} 1245 1246/* 1247 * Interface to hold a bunch of attributes. 1248 * used for creating new files. 1249 * attrsize is the total size of all attributes 1250 * to be added during object creation 1251 * 1252 * For updating/adding a single attribute dmu_tx_hold_sa() should be used. 1253 */ 1254 1255/* 1256 * hold necessary attribute name for attribute registration. 1257 * should be a very rare case where this is needed. If it does 1258 * happen it would only happen on the first write to the file system. 1259 */ 1260static void 1261dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx) 1262{ 1263 if (!sa->sa_need_attr_registration) 1264 return; 1265 1266 for (int i = 0; i != sa->sa_num_attrs; i++) { 1267 if (!sa->sa_attr_table[i].sa_registered) { 1268 if (sa->sa_reg_attr_obj) 1269 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj, 1270 B_TRUE, sa->sa_attr_table[i].sa_name); 1271 else 1272 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 1273 B_TRUE, sa->sa_attr_table[i].sa_name); 1274 } 1275 } 1276} 1277 1278void 1279dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object) 1280{ 1281 dmu_tx_hold_t *txh; 1282 1283 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, object, 1284 THT_SPILL, 0, 0); 1285 if (txh != NULL) 1286 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 1287 SPA_OLD_MAXBLOCKSIZE, FTAG); 1288} 1289 1290void 1291dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize) 1292{ 1293 sa_os_t *sa = tx->tx_objset->os_sa; 1294 1295 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1296 1297 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1298 return; 1299 1300 if (tx->tx_objset->os_sa->sa_layout_attr_obj) { 1301 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1302 } else { 1303 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1304 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1305 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1306 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1307 } 1308 1309 dmu_tx_sa_registration_hold(sa, tx); 1310 1311 if (attrsize <= DN_OLD_MAX_BONUSLEN && !sa->sa_force_spill) 1312 return; 1313 1314 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT, 1315 THT_SPILL, 0, 0); 1316} 1317 1318/* 1319 * Hold SA attribute 1320 * 1321 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size) 1322 * 1323 * variable_size is the total size of all variable sized attributes 1324 * passed to this function. It is not the total size of all 1325 * variable size attributes that *may* exist on this object. 1326 */ 1327void 1328dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow) 1329{ 1330 uint64_t object; 1331 sa_os_t *sa = tx->tx_objset->os_sa; 1332 1333 ASSERT(hdl != NULL); 1334 1335 object = sa_handle_object(hdl); 1336 1337 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus; 1338 DB_DNODE_ENTER(db); 1339 dmu_tx_hold_bonus_by_dnode(tx, DB_DNODE(db)); 1340 DB_DNODE_EXIT(db); 1341 1342 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1343 return; 1344 1345 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 || 1346 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) { 1347 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1348 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1349 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1350 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1351 } 1352 1353 dmu_tx_sa_registration_hold(sa, tx); 1354 1355 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj) 1356 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1357 1358 if (sa->sa_force_spill || may_grow || hdl->sa_spill) { 1359 ASSERT(tx->tx_txg == 0); 1360 dmu_tx_hold_spill(tx, object); 1361 } else { 1362 dnode_t *dn; 1363 1364 DB_DNODE_ENTER(db); 1365 dn = DB_DNODE(db); 1366 if (dn->dn_have_spill) { 1367 ASSERT(tx->tx_txg == 0); 1368 dmu_tx_hold_spill(tx, object); 1369 } 1370 DB_DNODE_EXIT(db); 1371 } 1372} 1373 1374void 1375dmu_tx_init(void) 1376{ 1377 dmu_tx_ksp = kstat_create("zfs", 0, "dmu_tx", "misc", 1378 KSTAT_TYPE_NAMED, sizeof (dmu_tx_stats) / sizeof (kstat_named_t), 1379 KSTAT_FLAG_VIRTUAL); 1380 1381 if (dmu_tx_ksp != NULL) { 1382 dmu_tx_ksp->ks_data = &dmu_tx_stats; 1383 kstat_install(dmu_tx_ksp); 1384 } 1385} 1386 1387void 1388dmu_tx_fini(void) 1389{ 1390 if (dmu_tx_ksp != NULL) { 1391 kstat_delete(dmu_tx_ksp); 1392 dmu_tx_ksp = NULL; 1393 } 1394} 1395 1396#if defined(_KERNEL) 1397EXPORT_SYMBOL(dmu_tx_create); 1398EXPORT_SYMBOL(dmu_tx_hold_write); 1399EXPORT_SYMBOL(dmu_tx_hold_write_by_dnode); 1400EXPORT_SYMBOL(dmu_tx_hold_free); 1401EXPORT_SYMBOL(dmu_tx_hold_free_by_dnode); 1402EXPORT_SYMBOL(dmu_tx_hold_zap); 1403EXPORT_SYMBOL(dmu_tx_hold_zap_by_dnode); 1404EXPORT_SYMBOL(dmu_tx_hold_bonus); 1405EXPORT_SYMBOL(dmu_tx_hold_bonus_by_dnode); 1406EXPORT_SYMBOL(dmu_tx_abort); 1407EXPORT_SYMBOL(dmu_tx_assign); 1408EXPORT_SYMBOL(dmu_tx_wait); 1409EXPORT_SYMBOL(dmu_tx_commit); 1410EXPORT_SYMBOL(dmu_tx_mark_netfree); 1411EXPORT_SYMBOL(dmu_tx_get_txg); 1412EXPORT_SYMBOL(dmu_tx_callback_register); 1413EXPORT_SYMBOL(dmu_tx_do_callbacks); 1414EXPORT_SYMBOL(dmu_tx_hold_spill); 1415EXPORT_SYMBOL(dmu_tx_hold_sa_create); 1416EXPORT_SYMBOL(dmu_tx_hold_sa); 1417#endif 1418