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 42 typedef void (*dmu_tx_hold_func_t)(dmu_tx_t *tx, struct dnode *dn, 43 uint64_t arg1, uint64_t arg2); 44 45 dmu_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 60 static kstat_t *dmu_tx_ksp; 61 62 dmu_tx_t * 63 dmu_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 77 dmu_tx_t * 78 dmu_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 85 dmu_tx_t * 86 dmu_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 98 int 99 dmu_tx_is_syncing(dmu_tx_t *tx) 100 { 101 return (tx->tx_anyobj); 102 } 103 104 int 105 dmu_tx_private_ok(dmu_tx_t *tx) 106 { 107 return (tx->tx_anyobj); 108 } 109 110 static dmu_tx_hold_t * 111 dmu_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 } 144 145 static dmu_tx_hold_t * 146 dmu_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 } 165 166 void 167 dmu_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 */ 205 static int 206 dmu_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 */ 222 static void 223 dmu_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 (zfs_refcount_count(&txh->txh_space_towrite) > 2 * DMU_MAX_ACCESS) 234 err = SET_ERROR(EFBIG); 235 236 if (dn == NULL) 237 return; 238 239 /* 240 * For i/o error checking, read the blocks that will be needed 241 * to perform the write: the first and last level-0 blocks (if 242 * they are not aligned, i.e. if they are partial-block writes), 243 * and all the level-1 blocks. 244 */ 245 if (dn->dn_maxblkid == 0) { 246 if (off < dn->dn_datablksz && 247 (off > 0 || len < dn->dn_datablksz)) { 248 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 249 if (err != 0) { 250 txh->txh_tx->tx_err = err; 251 } 252 } 253 } else { 254 zio_t *zio = zio_root(dn->dn_objset->os_spa, 255 NULL, NULL, ZIO_FLAG_CANFAIL); 256 257 /* first level-0 block */ 258 uint64_t start = off >> dn->dn_datablkshift; 259 if (P2PHASE(off, dn->dn_datablksz) || len < dn->dn_datablksz) { 260 err = dmu_tx_check_ioerr(zio, dn, 0, start); 261 if (err != 0) { 262 txh->txh_tx->tx_err = err; 263 } 264 } 265 266 /* last level-0 block */ 267 uint64_t end = (off + len - 1) >> dn->dn_datablkshift; 268 if (end != start && end <= dn->dn_maxblkid && 269 P2PHASE(off + len, dn->dn_datablksz)) { 270 err = dmu_tx_check_ioerr(zio, dn, 0, end); 271 if (err != 0) { 272 txh->txh_tx->tx_err = err; 273 } 274 } 275 276 /* level-1 blocks */ 277 if (dn->dn_nlevels > 1) { 278 int shft = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 279 for (uint64_t i = (start >> shft) + 1; 280 i < end >> shft; i++) { 281 err = dmu_tx_check_ioerr(zio, dn, 1, i); 282 if (err != 0) { 283 txh->txh_tx->tx_err = err; 284 } 285 } 286 } 287 288 err = zio_wait(zio); 289 if (err != 0) { 290 txh->txh_tx->tx_err = err; 291 } 292 } 293 } 294 295 static void 296 dmu_tx_count_dnode(dmu_tx_hold_t *txh) 297 { 298 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 299 DNODE_MIN_SIZE, FTAG); 300 } 301 302 void 303 dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len) 304 { 305 dmu_tx_hold_t *txh; 306 307 ASSERT0(tx->tx_txg); 308 ASSERT3U(len, <=, DMU_MAX_ACCESS); 309 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 310 311 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 312 object, 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 void 320 dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len) 321 { 322 dmu_tx_hold_t *txh; 323 324 ASSERT0(tx->tx_txg); 325 ASSERT3U(len, <=, DMU_MAX_ACCESS); 326 ASSERT(len == 0 || UINT64_MAX - off >= len - 1); 327 328 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_WRITE, off, len); 329 if (txh != NULL) { 330 dmu_tx_count_write(txh, off, len); 331 dmu_tx_count_dnode(txh); 332 } 333 } 334 335 /* 336 * This function marks the transaction as being a "net free". The end 337 * result is that refquotas will be disabled for this transaction, and 338 * this transaction will be able to use half of the pool space overhead 339 * (see dsl_pool_adjustedsize()). Therefore this function should only 340 * be called for transactions that we expect will not cause a net increase 341 * in the amount of space used (but it's OK if that is occasionally not true). 342 */ 343 void 344 dmu_tx_mark_netfree(dmu_tx_t *tx) 345 { 346 tx->tx_netfree = B_TRUE; 347 } 348 349 static void 350 dmu_tx_hold_free_impl(dmu_tx_hold_t *txh, uint64_t off, uint64_t len) 351 { 352 dmu_tx_t *tx = txh->txh_tx; 353 dnode_t *dn = txh->txh_dnode; 354 int err; 355 356 ASSERT(tx->tx_txg == 0); 357 358 dmu_tx_count_dnode(txh); 359 360 if (off >= (dn->dn_maxblkid + 1) * dn->dn_datablksz) 361 return; 362 if (len == DMU_OBJECT_END) 363 len = (dn->dn_maxblkid + 1) * dn->dn_datablksz - off; 364 365 dmu_tx_count_dnode(txh); 366 367 /* 368 * For i/o error checking, we read the first and last level-0 369 * blocks if they are not aligned, and all the level-1 blocks. 370 * 371 * Note: dbuf_free_range() assumes that we have not instantiated 372 * any level-0 dbufs that will be completely freed. Therefore we must 373 * exercise care to not read or count the first and last blocks 374 * if they are blocksize-aligned. 375 */ 376 if (dn->dn_datablkshift == 0) { 377 if (off != 0 || len < dn->dn_datablksz) 378 dmu_tx_count_write(txh, 0, dn->dn_datablksz); 379 } else { 380 /* first block will be modified if it is not aligned */ 381 if (!IS_P2ALIGNED(off, 1 << dn->dn_datablkshift)) 382 dmu_tx_count_write(txh, off, 1); 383 /* last block will be modified if it is not aligned */ 384 if (!IS_P2ALIGNED(off + len, 1 << dn->dn_datablkshift)) 385 dmu_tx_count_write(txh, off + len, 1); 386 } 387 388 /* 389 * Check level-1 blocks. 390 */ 391 if (dn->dn_nlevels > 1) { 392 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 393 SPA_BLKPTRSHIFT; 394 uint64_t start = off >> shift; 395 uint64_t end = (off + len) >> shift; 396 397 ASSERT(dn->dn_indblkshift != 0); 398 399 /* 400 * dnode_reallocate() can result in an object with indirect 401 * blocks having an odd data block size. In this case, 402 * just check the single block. 403 */ 404 if (dn->dn_datablkshift == 0) 405 start = end = 0; 406 407 zio_t *zio = zio_root(tx->tx_pool->dp_spa, 408 NULL, NULL, ZIO_FLAG_CANFAIL); 409 for (uint64_t i = start; i <= end; i++) { 410 uint64_t ibyte = i << shift; 411 err = dnode_next_offset(dn, 0, &ibyte, 2, 1, 0); 412 i = ibyte >> shift; 413 if (err == ESRCH || i > end) 414 break; 415 if (err != 0) { 416 tx->tx_err = err; 417 (void) zio_wait(zio); 418 return; 419 } 420 421 (void) zfs_refcount_add_many(&txh->txh_memory_tohold, 422 1 << dn->dn_indblkshift, FTAG); 423 424 err = dmu_tx_check_ioerr(zio, dn, 1, i); 425 if (err != 0) { 426 tx->tx_err = err; 427 (void) zio_wait(zio); 428 return; 429 } 430 } 431 err = zio_wait(zio); 432 if (err != 0) { 433 tx->tx_err = err; 434 return; 435 } 436 } 437 } 438 439 void 440 dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len) 441 { 442 dmu_tx_hold_t *txh; 443 444 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 445 object, THT_FREE, off, len); 446 if (txh != NULL) 447 (void) dmu_tx_hold_free_impl(txh, off, len); 448 } 449 450 void 451 dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, uint64_t len) 452 { 453 dmu_tx_hold_t *txh; 454 455 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_FREE, off, len); 456 if (txh != NULL) 457 (void) dmu_tx_hold_free_impl(txh, off, len); 458 } 459 460 static void 461 dmu_tx_hold_zap_impl(dmu_tx_hold_t *txh, const char *name) 462 { 463 dmu_tx_t *tx = txh->txh_tx; 464 dnode_t *dn = txh->txh_dnode; 465 int err; 466 467 ASSERT(tx->tx_txg == 0); 468 469 dmu_tx_count_dnode(txh); 470 471 /* 472 * Modifying a almost-full microzap is around the worst case (128KB) 473 * 474 * If it is a fat zap, the worst case would be 7*16KB=112KB: 475 * - 3 blocks overwritten: target leaf, ptrtbl block, header block 476 * - 4 new blocks written if adding: 477 * - 2 blocks for possibly split leaves, 478 * - 2 grown ptrtbl blocks 479 */ 480 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 481 MZAP_MAX_BLKSZ, FTAG); 482 483 if (dn == NULL) 484 return; 485 486 ASSERT3U(DMU_OT_BYTESWAP(dn->dn_type), ==, DMU_BSWAP_ZAP); 487 488 if (dn->dn_maxblkid == 0 || name == NULL) { 489 /* 490 * This is a microzap (only one block), or we don't know 491 * the name. Check the first block for i/o errors. 492 */ 493 err = dmu_tx_check_ioerr(NULL, dn, 0, 0); 494 if (err != 0) { 495 tx->tx_err = err; 496 } 497 } else { 498 /* 499 * Access the name so that we'll check for i/o errors to 500 * the leaf blocks, etc. We ignore ENOENT, as this name 501 * may not yet exist. 502 */ 503 err = zap_lookup_by_dnode(dn, name, 8, 0, NULL); 504 if (err == EIO || err == ECKSUM || err == ENXIO) { 505 tx->tx_err = err; 506 } 507 } 508 } 509 510 void 511 dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name) 512 { 513 dmu_tx_hold_t *txh; 514 515 ASSERT0(tx->tx_txg); 516 517 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 518 object, THT_ZAP, add, (uintptr_t)name); 519 if (txh != NULL) 520 dmu_tx_hold_zap_impl(txh, name); 521 } 522 523 void 524 dmu_tx_hold_zap_by_dnode(dmu_tx_t *tx, dnode_t *dn, int add, const char *name) 525 { 526 dmu_tx_hold_t *txh; 527 528 ASSERT0(tx->tx_txg); 529 ASSERT(dn != NULL); 530 531 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_ZAP, add, (uintptr_t)name); 532 if (txh != NULL) 533 dmu_tx_hold_zap_impl(txh, name); 534 } 535 536 void 537 dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object) 538 { 539 dmu_tx_hold_t *txh; 540 541 ASSERT(tx->tx_txg == 0); 542 543 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 544 object, THT_BONUS, 0, 0); 545 if (txh) 546 dmu_tx_count_dnode(txh); 547 } 548 549 void 550 dmu_tx_hold_bonus_by_dnode(dmu_tx_t *tx, dnode_t *dn) 551 { 552 dmu_tx_hold_t *txh; 553 554 ASSERT0(tx->tx_txg); 555 556 txh = dmu_tx_hold_dnode_impl(tx, dn, THT_BONUS, 0, 0); 557 if (txh) 558 dmu_tx_count_dnode(txh); 559 } 560 561 void 562 dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space) 563 { 564 dmu_tx_hold_t *txh; 565 566 ASSERT(tx->tx_txg == 0); 567 568 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, 569 DMU_NEW_OBJECT, THT_SPACE, space, 0); 570 if (txh) { 571 (void) zfs_refcount_add_many( 572 &txh->txh_space_towrite, space, FTAG); 573 } 574 } 575 576 #ifdef ZFS_DEBUG 577 void 578 dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db) 579 { 580 boolean_t match_object = B_FALSE; 581 boolean_t match_offset = B_FALSE; 582 583 DB_DNODE_ENTER(db); 584 dnode_t *dn = DB_DNODE(db); 585 ASSERT(tx->tx_txg != 0); 586 ASSERT(tx->tx_objset == NULL || dn->dn_objset == tx->tx_objset); 587 ASSERT3U(dn->dn_object, ==, db->db.db_object); 588 589 if (tx->tx_anyobj) { 590 DB_DNODE_EXIT(db); 591 return; 592 } 593 594 /* XXX No checking on the meta dnode for now */ 595 if (db->db.db_object == DMU_META_DNODE_OBJECT) { 596 DB_DNODE_EXIT(db); 597 return; 598 } 599 600 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 601 txh = list_next(&tx->tx_holds, txh)) { 602 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 603 if (txh->txh_dnode == dn && txh->txh_type != THT_NEWOBJECT) 604 match_object = TRUE; 605 if (txh->txh_dnode == NULL || txh->txh_dnode == dn) { 606 int datablkshift = dn->dn_datablkshift ? 607 dn->dn_datablkshift : SPA_MAXBLOCKSHIFT; 608 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 609 int shift = datablkshift + epbs * db->db_level; 610 uint64_t beginblk = shift >= 64 ? 0 : 611 (txh->txh_arg1 >> shift); 612 uint64_t endblk = shift >= 64 ? 0 : 613 ((txh->txh_arg1 + txh->txh_arg2 - 1) >> shift); 614 uint64_t blkid = db->db_blkid; 615 616 /* XXX txh_arg2 better not be zero... */ 617 618 dprintf("found txh type %x beginblk=%llx endblk=%llx\n", 619 txh->txh_type, beginblk, endblk); 620 621 switch (txh->txh_type) { 622 case THT_WRITE: 623 if (blkid >= beginblk && blkid <= endblk) 624 match_offset = TRUE; 625 /* 626 * We will let this hold work for the bonus 627 * or spill buffer so that we don't need to 628 * hold it when creating a new object. 629 */ 630 if (blkid == DMU_BONUS_BLKID || 631 blkid == DMU_SPILL_BLKID) 632 match_offset = TRUE; 633 /* 634 * They might have to increase nlevels, 635 * thus dirtying the new TLIBs. Or the 636 * might have to change the block size, 637 * thus dirying the new lvl=0 blk=0. 638 */ 639 if (blkid == 0) 640 match_offset = TRUE; 641 break; 642 case THT_FREE: 643 /* 644 * We will dirty all the level 1 blocks in 645 * the free range and perhaps the first and 646 * last level 0 block. 647 */ 648 if (blkid >= beginblk && (blkid <= endblk || 649 txh->txh_arg2 == DMU_OBJECT_END)) 650 match_offset = TRUE; 651 break; 652 case THT_SPILL: 653 if (blkid == DMU_SPILL_BLKID) 654 match_offset = TRUE; 655 break; 656 case THT_BONUS: 657 if (blkid == DMU_BONUS_BLKID) 658 match_offset = TRUE; 659 break; 660 case THT_ZAP: 661 match_offset = TRUE; 662 break; 663 case THT_NEWOBJECT: 664 match_object = TRUE; 665 break; 666 default: 667 cmn_err(CE_PANIC, "bad txh_type %d", 668 txh->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 = 100 * MICROSEC; /* 100 milliseconds */ 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 min_tx_time = MIN(min_tx_time, zfs_delay_max_ns); 804 if (now > tx->tx_start + min_tx_time) 805 return; 806 807 DTRACE_PROBE3(delay__mintime, dmu_tx_t *, tx, uint64_t, dirty, 808 uint64_t, min_tx_time); 809 810 mutex_enter(&dp->dp_lock); 811 wakeup = MAX(tx->tx_start + min_tx_time, 812 dp->dp_last_wakeup + min_tx_time); 813 dp->dp_last_wakeup = wakeup; 814 mutex_exit(&dp->dp_lock); 815 816 zfs_sleep_until(wakeup); 817 } 818 819 /* 820 * This routine attempts to assign the transaction to a transaction group. 821 * To do so, we must determine if there is sufficient free space on disk. 822 * 823 * If this is a "netfree" transaction (i.e. we called dmu_tx_mark_netfree() 824 * on it), then it is assumed that there is sufficient free space, 825 * unless there's insufficient slop space in the pool (see the comment 826 * above spa_slop_shift in spa_misc.c). 827 * 828 * If it is not a "netfree" transaction, then if the data already on disk 829 * is over the allowed usage (e.g. quota), this will fail with EDQUOT or 830 * ENOSPC. Otherwise, if the current rough estimate of pending changes, 831 * plus the rough estimate of this transaction's changes, may exceed the 832 * allowed usage, then this will fail with ERESTART, which will cause the 833 * caller to wait for the pending changes to be written to disk (by waiting 834 * for the next TXG to open), and then check the space usage again. 835 * 836 * The rough estimate of pending changes is comprised of the sum of: 837 * 838 * - this transaction's holds' txh_space_towrite 839 * 840 * - dd_tempreserved[], which is the sum of in-flight transactions' 841 * holds' txh_space_towrite (i.e. those transactions that have called 842 * dmu_tx_assign() but not yet called dmu_tx_commit()). 843 * 844 * - dd_space_towrite[], which is the amount of dirtied dbufs. 845 * 846 * Note that all of these values are inflated by spa_get_worst_case_asize(), 847 * which means that we may get ERESTART well before we are actually in danger 848 * of running out of space, but this also mitigates any small inaccuracies 849 * in the rough estimate (e.g. txh_space_towrite doesn't take into account 850 * indirect blocks, and dd_space_towrite[] doesn't take into account changes 851 * to the MOS). 852 * 853 * Note that due to this algorithm, it is possible to exceed the allowed 854 * usage by one transaction. Also, as we approach the allowed usage, 855 * we will allow a very limited amount of changes into each TXG, thus 856 * decreasing performance. 857 */ 858 static int 859 dmu_tx_try_assign(dmu_tx_t *tx, uint64_t txg_how) 860 { 861 spa_t *spa = tx->tx_pool->dp_spa; 862 863 ASSERT0(tx->tx_txg); 864 865 if (tx->tx_err) { 866 DMU_TX_STAT_BUMP(dmu_tx_error); 867 return (tx->tx_err); 868 } 869 870 if (spa_suspended(spa)) { 871 DMU_TX_STAT_BUMP(dmu_tx_suspended); 872 873 /* 874 * If the user has indicated a blocking failure mode 875 * then return ERESTART which will block in dmu_tx_wait(). 876 * Otherwise, return EIO so that an error can get 877 * propagated back to the VOP calls. 878 * 879 * Note that we always honor the txg_how flag regardless 880 * of the failuremode setting. 881 */ 882 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE && 883 !(txg_how & TXG_WAIT)) 884 return (SET_ERROR(EIO)); 885 886 return (SET_ERROR(ERESTART)); 887 } 888 889 if (!tx->tx_dirty_delayed && 890 dsl_pool_need_dirty_delay(tx->tx_pool)) { 891 tx->tx_wait_dirty = B_TRUE; 892 DMU_TX_STAT_BUMP(dmu_tx_dirty_delay); 893 return (SET_ERROR(ERESTART)); 894 } 895 896 tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh); 897 tx->tx_needassign_txh = NULL; 898 899 /* 900 * NB: No error returns are allowed after txg_hold_open, but 901 * before processing the dnode holds, due to the 902 * dmu_tx_unassign() logic. 903 */ 904 905 uint64_t towrite = 0; 906 uint64_t tohold = 0; 907 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 908 txh = list_next(&tx->tx_holds, txh)) { 909 dnode_t *dn = txh->txh_dnode; 910 if (dn != NULL) { 911 /* 912 * This thread can't hold the dn_struct_rwlock 913 * while assigning the tx, because this can lead to 914 * deadlock. Specifically, if this dnode is already 915 * assigned to an earlier txg, this thread may need 916 * to wait for that txg to sync (the ERESTART case 917 * below). The other thread that has assigned this 918 * dnode to an earlier txg prevents this txg from 919 * syncing until its tx can complete (calling 920 * dmu_tx_commit()), but it may need to acquire the 921 * dn_struct_rwlock to do so (e.g. via 922 * dmu_buf_hold*()). 923 * 924 * Note that this thread can't hold the lock for 925 * read either, but the rwlock doesn't record 926 * enough information to make that assertion. 927 */ 928 ASSERT(!RW_WRITE_HELD(&dn->dn_struct_rwlock)); 929 930 mutex_enter(&dn->dn_mtx); 931 if (dn->dn_assigned_txg == tx->tx_txg - 1) { 932 mutex_exit(&dn->dn_mtx); 933 tx->tx_needassign_txh = txh; 934 DMU_TX_STAT_BUMP(dmu_tx_group); 935 return (SET_ERROR(ERESTART)); 936 } 937 if (dn->dn_assigned_txg == 0) 938 dn->dn_assigned_txg = tx->tx_txg; 939 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 940 (void) zfs_refcount_add(&dn->dn_tx_holds, tx); 941 mutex_exit(&dn->dn_mtx); 942 } 943 towrite += zfs_refcount_count(&txh->txh_space_towrite); 944 tohold += zfs_refcount_count(&txh->txh_memory_tohold); 945 } 946 947 /* needed allocation: worst-case estimate of write space */ 948 uint64_t asize = spa_get_worst_case_asize(tx->tx_pool->dp_spa, towrite); 949 /* calculate memory footprint estimate */ 950 uint64_t memory = towrite + tohold; 951 952 if (tx->tx_dir != NULL && asize != 0) { 953 int err = dsl_dir_tempreserve_space(tx->tx_dir, memory, 954 asize, tx->tx_netfree, &tx->tx_tempreserve_cookie, tx); 955 if (err != 0) 956 return (err); 957 } 958 959 DMU_TX_STAT_BUMP(dmu_tx_assigned); 960 961 return (0); 962 } 963 964 static void 965 dmu_tx_unassign(dmu_tx_t *tx) 966 { 967 if (tx->tx_txg == 0) 968 return; 969 970 txg_rele_to_quiesce(&tx->tx_txgh); 971 972 /* 973 * Walk the transaction's hold list, removing the hold on the 974 * associated dnode, and notifying waiters if the refcount drops to 0. 975 */ 976 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); 977 txh && txh != tx->tx_needassign_txh; 978 txh = list_next(&tx->tx_holds, txh)) { 979 dnode_t *dn = txh->txh_dnode; 980 981 if (dn == NULL) 982 continue; 983 mutex_enter(&dn->dn_mtx); 984 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 985 986 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 987 dn->dn_assigned_txg = 0; 988 cv_broadcast(&dn->dn_notxholds); 989 } 990 mutex_exit(&dn->dn_mtx); 991 } 992 993 txg_rele_to_sync(&tx->tx_txgh); 994 995 tx->tx_lasttried_txg = tx->tx_txg; 996 tx->tx_txg = 0; 997 } 998 999 /* 1000 * Assign tx to a transaction group; txg_how is a bitmask: 1001 * 1002 * If TXG_WAIT is set and the currently open txg is full, this function 1003 * will wait until there's a new txg. This should be used when no locks 1004 * are being held. With this bit set, this function will only fail if 1005 * we're truly out of space (or over quota). 1006 * 1007 * If TXG_WAIT is *not* set and we can't assign into the currently open 1008 * txg without blocking, this function will return immediately with 1009 * ERESTART. This should be used whenever locks are being held. On an 1010 * ERESTART error, the caller should drop all locks, call dmu_tx_wait(), 1011 * and try again. 1012 * 1013 * If TXG_NOTHROTTLE is set, this indicates that this tx should not be 1014 * delayed due on the ZFS Write Throttle (see comments in dsl_pool.c for 1015 * details on the throttle). This is used by the VFS operations, after 1016 * they have already called dmu_tx_wait() (though most likely on a 1017 * different tx). 1018 */ 1019 int 1020 dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how) 1021 { 1022 int err; 1023 1024 ASSERT(tx->tx_txg == 0); 1025 ASSERT0(txg_how & ~(TXG_WAIT | TXG_NOTHROTTLE)); 1026 ASSERT(!dsl_pool_sync_context(tx->tx_pool)); 1027 1028 /* If we might wait, we must not hold the config lock. */ 1029 IMPLY((txg_how & TXG_WAIT), !dsl_pool_config_held(tx->tx_pool)); 1030 1031 if ((txg_how & TXG_NOTHROTTLE)) 1032 tx->tx_dirty_delayed = B_TRUE; 1033 1034 while ((err = dmu_tx_try_assign(tx, txg_how)) != 0) { 1035 dmu_tx_unassign(tx); 1036 1037 if (err != ERESTART || !(txg_how & TXG_WAIT)) 1038 return (err); 1039 1040 dmu_tx_wait(tx); 1041 } 1042 1043 txg_rele_to_quiesce(&tx->tx_txgh); 1044 1045 return (0); 1046 } 1047 1048 void 1049 dmu_tx_wait(dmu_tx_t *tx) 1050 { 1051 spa_t *spa = tx->tx_pool->dp_spa; 1052 dsl_pool_t *dp = tx->tx_pool; 1053 hrtime_t before; 1054 1055 ASSERT(tx->tx_txg == 0); 1056 ASSERT(!dsl_pool_config_held(tx->tx_pool)); 1057 1058 before = gethrtime(); 1059 1060 if (tx->tx_wait_dirty) { 1061 uint64_t dirty; 1062 1063 /* 1064 * dmu_tx_try_assign() has determined that we need to wait 1065 * because we've consumed much or all of the dirty buffer 1066 * space. 1067 */ 1068 mutex_enter(&dp->dp_lock); 1069 if (dp->dp_dirty_total >= zfs_dirty_data_max) 1070 DMU_TX_STAT_BUMP(dmu_tx_dirty_over_max); 1071 while (dp->dp_dirty_total >= zfs_dirty_data_max) 1072 cv_wait(&dp->dp_spaceavail_cv, &dp->dp_lock); 1073 dirty = dp->dp_dirty_total; 1074 mutex_exit(&dp->dp_lock); 1075 1076 dmu_tx_delay(tx, dirty); 1077 1078 tx->tx_wait_dirty = B_FALSE; 1079 1080 /* 1081 * Note: setting tx_dirty_delayed only has effect if the 1082 * caller used TX_WAIT. Otherwise they are going to 1083 * destroy this tx and try again. The common case, 1084 * zfs_write(), uses TX_WAIT. 1085 */ 1086 tx->tx_dirty_delayed = B_TRUE; 1087 } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { 1088 /* 1089 * If the pool is suspended we need to wait until it 1090 * is resumed. Note that it's possible that the pool 1091 * has become active after this thread has tried to 1092 * obtain a tx. If that's the case then tx_lasttried_txg 1093 * would not have been set. 1094 */ 1095 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1096 } else if (tx->tx_needassign_txh) { 1097 dnode_t *dn = tx->tx_needassign_txh->txh_dnode; 1098 1099 mutex_enter(&dn->dn_mtx); 1100 while (dn->dn_assigned_txg == tx->tx_lasttried_txg - 1) 1101 cv_wait(&dn->dn_notxholds, &dn->dn_mtx); 1102 mutex_exit(&dn->dn_mtx); 1103 tx->tx_needassign_txh = NULL; 1104 } else { 1105 /* 1106 * If we have a lot of dirty data just wait until we sync 1107 * out a TXG at which point we'll hopefully have synced 1108 * a portion of the changes. 1109 */ 1110 txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); 1111 } 1112 1113 spa_tx_assign_add_nsecs(spa, gethrtime() - before); 1114 } 1115 1116 static void 1117 dmu_tx_destroy(dmu_tx_t *tx) 1118 { 1119 dmu_tx_hold_t *txh; 1120 1121 while ((txh = list_head(&tx->tx_holds)) != NULL) { 1122 dnode_t *dn = txh->txh_dnode; 1123 1124 list_remove(&tx->tx_holds, txh); 1125 zfs_refcount_destroy_many(&txh->txh_space_towrite, 1126 zfs_refcount_count(&txh->txh_space_towrite)); 1127 zfs_refcount_destroy_many(&txh->txh_memory_tohold, 1128 zfs_refcount_count(&txh->txh_memory_tohold)); 1129 kmem_free(txh, sizeof (dmu_tx_hold_t)); 1130 if (dn != NULL) 1131 dnode_rele(dn, tx); 1132 } 1133 1134 list_destroy(&tx->tx_callbacks); 1135 list_destroy(&tx->tx_holds); 1136 kmem_free(tx, sizeof (dmu_tx_t)); 1137 } 1138 1139 void 1140 dmu_tx_commit(dmu_tx_t *tx) 1141 { 1142 ASSERT(tx->tx_txg != 0); 1143 1144 /* 1145 * Go through the transaction's hold list and remove holds on 1146 * associated dnodes, notifying waiters if no holds remain. 1147 */ 1148 for (dmu_tx_hold_t *txh = list_head(&tx->tx_holds); txh != NULL; 1149 txh = list_next(&tx->tx_holds, txh)) { 1150 dnode_t *dn = txh->txh_dnode; 1151 1152 if (dn == NULL) 1153 continue; 1154 1155 mutex_enter(&dn->dn_mtx); 1156 ASSERT3U(dn->dn_assigned_txg, ==, tx->tx_txg); 1157 1158 if (zfs_refcount_remove(&dn->dn_tx_holds, tx) == 0) { 1159 dn->dn_assigned_txg = 0; 1160 cv_broadcast(&dn->dn_notxholds); 1161 } 1162 mutex_exit(&dn->dn_mtx); 1163 } 1164 1165 if (tx->tx_tempreserve_cookie) 1166 dsl_dir_tempreserve_clear(tx->tx_tempreserve_cookie, tx); 1167 1168 if (!list_is_empty(&tx->tx_callbacks)) 1169 txg_register_callbacks(&tx->tx_txgh, &tx->tx_callbacks); 1170 1171 if (tx->tx_anyobj == FALSE) 1172 txg_rele_to_sync(&tx->tx_txgh); 1173 1174 dmu_tx_destroy(tx); 1175 } 1176 1177 void 1178 dmu_tx_abort(dmu_tx_t *tx) 1179 { 1180 ASSERT(tx->tx_txg == 0); 1181 1182 /* 1183 * Call any registered callbacks with an error code. 1184 */ 1185 if (!list_is_empty(&tx->tx_callbacks)) 1186 dmu_tx_do_callbacks(&tx->tx_callbacks, SET_ERROR(ECANCELED)); 1187 1188 dmu_tx_destroy(tx); 1189 } 1190 1191 uint64_t 1192 dmu_tx_get_txg(dmu_tx_t *tx) 1193 { 1194 ASSERT(tx->tx_txg != 0); 1195 return (tx->tx_txg); 1196 } 1197 1198 dsl_pool_t * 1199 dmu_tx_pool(dmu_tx_t *tx) 1200 { 1201 ASSERT(tx->tx_pool != NULL); 1202 return (tx->tx_pool); 1203 } 1204 1205 void 1206 dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data) 1207 { 1208 dmu_tx_callback_t *dcb; 1209 1210 dcb = kmem_alloc(sizeof (dmu_tx_callback_t), KM_SLEEP); 1211 1212 dcb->dcb_func = func; 1213 dcb->dcb_data = data; 1214 1215 list_insert_tail(&tx->tx_callbacks, dcb); 1216 } 1217 1218 /* 1219 * Call all the commit callbacks on a list, with a given error code. 1220 */ 1221 void 1222 dmu_tx_do_callbacks(list_t *cb_list, int error) 1223 { 1224 dmu_tx_callback_t *dcb; 1225 1226 while ((dcb = list_tail(cb_list)) != NULL) { 1227 list_remove(cb_list, dcb); 1228 dcb->dcb_func(dcb->dcb_data, error); 1229 kmem_free(dcb, sizeof (dmu_tx_callback_t)); 1230 } 1231 } 1232 1233 /* 1234 * Interface to hold a bunch of attributes. 1235 * used for creating new files. 1236 * attrsize is the total size of all attributes 1237 * to be added during object creation 1238 * 1239 * For updating/adding a single attribute dmu_tx_hold_sa() should be used. 1240 */ 1241 1242 /* 1243 * hold necessary attribute name for attribute registration. 1244 * should be a very rare case where this is needed. If it does 1245 * happen it would only happen on the first write to the file system. 1246 */ 1247 static void 1248 dmu_tx_sa_registration_hold(sa_os_t *sa, dmu_tx_t *tx) 1249 { 1250 if (!sa->sa_need_attr_registration) 1251 return; 1252 1253 for (int i = 0; i != sa->sa_num_attrs; i++) { 1254 if (!sa->sa_attr_table[i].sa_registered) { 1255 if (sa->sa_reg_attr_obj) 1256 dmu_tx_hold_zap(tx, sa->sa_reg_attr_obj, 1257 B_TRUE, sa->sa_attr_table[i].sa_name); 1258 else 1259 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 1260 B_TRUE, sa->sa_attr_table[i].sa_name); 1261 } 1262 } 1263 } 1264 1265 void 1266 dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object) 1267 { 1268 dmu_tx_hold_t *txh; 1269 1270 txh = dmu_tx_hold_object_impl(tx, tx->tx_objset, object, 1271 THT_SPILL, 0, 0); 1272 if (txh != NULL) 1273 (void) zfs_refcount_add_many(&txh->txh_space_towrite, 1274 SPA_OLD_MAXBLOCKSIZE, FTAG); 1275 } 1276 1277 void 1278 dmu_tx_hold_sa_create(dmu_tx_t *tx, int attrsize) 1279 { 1280 sa_os_t *sa = tx->tx_objset->os_sa; 1281 1282 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1283 1284 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1285 return; 1286 1287 if (tx->tx_objset->os_sa->sa_layout_attr_obj) { 1288 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1289 } else { 1290 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1291 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1292 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1293 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1294 } 1295 1296 dmu_tx_sa_registration_hold(sa, tx); 1297 1298 if (attrsize <= DN_OLD_MAX_BONUSLEN && !sa->sa_force_spill) 1299 return; 1300 1301 (void) dmu_tx_hold_object_impl(tx, tx->tx_objset, DMU_NEW_OBJECT, 1302 THT_SPILL, 0, 0); 1303 } 1304 1305 /* 1306 * Hold SA attribute 1307 * 1308 * dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *, attribute, add, size) 1309 * 1310 * variable_size is the total size of all variable sized attributes 1311 * passed to this function. It is not the total size of all 1312 * variable size attributes that *may* exist on this object. 1313 */ 1314 void 1315 dmu_tx_hold_sa(dmu_tx_t *tx, sa_handle_t *hdl, boolean_t may_grow) 1316 { 1317 uint64_t object; 1318 sa_os_t *sa = tx->tx_objset->os_sa; 1319 1320 ASSERT(hdl != NULL); 1321 1322 object = sa_handle_object(hdl); 1323 1324 dmu_buf_impl_t *db = (dmu_buf_impl_t *)hdl->sa_bonus; 1325 DB_DNODE_ENTER(db); 1326 dmu_tx_hold_bonus_by_dnode(tx, DB_DNODE(db)); 1327 DB_DNODE_EXIT(db); 1328 1329 if (tx->tx_objset->os_sa->sa_master_obj == 0) 1330 return; 1331 1332 if (tx->tx_objset->os_sa->sa_reg_attr_obj == 0 || 1333 tx->tx_objset->os_sa->sa_layout_attr_obj == 0) { 1334 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_LAYOUTS); 1335 dmu_tx_hold_zap(tx, sa->sa_master_obj, B_TRUE, SA_REGISTRY); 1336 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1337 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, B_TRUE, NULL); 1338 } 1339 1340 dmu_tx_sa_registration_hold(sa, tx); 1341 1342 if (may_grow && tx->tx_objset->os_sa->sa_layout_attr_obj) 1343 dmu_tx_hold_zap(tx, sa->sa_layout_attr_obj, B_TRUE, NULL); 1344 1345 if (sa->sa_force_spill || may_grow || hdl->sa_spill) { 1346 ASSERT(tx->tx_txg == 0); 1347 dmu_tx_hold_spill(tx, object); 1348 } else { 1349 dnode_t *dn; 1350 1351 DB_DNODE_ENTER(db); 1352 dn = DB_DNODE(db); 1353 if (dn->dn_have_spill) { 1354 ASSERT(tx->tx_txg == 0); 1355 dmu_tx_hold_spill(tx, object); 1356 } 1357 DB_DNODE_EXIT(db); 1358 } 1359 } 1360 1361 void 1362 dmu_tx_init(void) 1363 { 1364 dmu_tx_ksp = kstat_create("zfs", 0, "dmu_tx", "misc", 1365 KSTAT_TYPE_NAMED, sizeof (dmu_tx_stats) / sizeof (kstat_named_t), 1366 KSTAT_FLAG_VIRTUAL); 1367 1368 if (dmu_tx_ksp != NULL) { 1369 dmu_tx_ksp->ks_data = &dmu_tx_stats; 1370 kstat_install(dmu_tx_ksp); 1371 } 1372 } 1373 1374 void 1375 dmu_tx_fini(void) 1376 { 1377 if (dmu_tx_ksp != NULL) { 1378 kstat_delete(dmu_tx_ksp); 1379 dmu_tx_ksp = NULL; 1380 } 1381 } 1382 1383 #if defined(_KERNEL) 1384 EXPORT_SYMBOL(dmu_tx_create); 1385 EXPORT_SYMBOL(dmu_tx_hold_write); 1386 EXPORT_SYMBOL(dmu_tx_hold_write_by_dnode); 1387 EXPORT_SYMBOL(dmu_tx_hold_free); 1388 EXPORT_SYMBOL(dmu_tx_hold_free_by_dnode); 1389 EXPORT_SYMBOL(dmu_tx_hold_zap); 1390 EXPORT_SYMBOL(dmu_tx_hold_zap_by_dnode); 1391 EXPORT_SYMBOL(dmu_tx_hold_bonus); 1392 EXPORT_SYMBOL(dmu_tx_hold_bonus_by_dnode); 1393 EXPORT_SYMBOL(dmu_tx_abort); 1394 EXPORT_SYMBOL(dmu_tx_assign); 1395 EXPORT_SYMBOL(dmu_tx_wait); 1396 EXPORT_SYMBOL(dmu_tx_commit); 1397 EXPORT_SYMBOL(dmu_tx_mark_netfree); 1398 EXPORT_SYMBOL(dmu_tx_get_txg); 1399 EXPORT_SYMBOL(dmu_tx_callback_register); 1400 EXPORT_SYMBOL(dmu_tx_do_callbacks); 1401 EXPORT_SYMBOL(dmu_tx_hold_spill); 1402 EXPORT_SYMBOL(dmu_tx_hold_sa_create); 1403 EXPORT_SYMBOL(dmu_tx_hold_sa); 1404 #endif 1405