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 https://opensource.org/licenses/CDDL-1.0. 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 (c) 2011, 2020 by Delphix. All rights reserved. 24 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. 25 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 26 * Copyright (c) 2016, Nexenta Systems, Inc. All rights reserved. 27 * Copyright (c) 2015 by Chunwei Chen. All rights reserved. 28 * Copyright (c) 2019 Datto Inc. 29 * Copyright (c) 2019, Klara Inc. 30 * Copyright (c) 2019, Allan Jude 31 * Copyright (c) 2022 Hewlett Packard Enterprise Development LP. 32 * Copyright (c) 2021, 2022 by Pawel Jakub Dawidek 33 */ 34 35 #include <sys/dmu.h> 36 #include <sys/dmu_impl.h> 37 #include <sys/dmu_tx.h> 38 #include <sys/dbuf.h> 39 #include <sys/dnode.h> 40 #include <sys/zfs_context.h> 41 #include <sys/dmu_objset.h> 42 #include <sys/dmu_traverse.h> 43 #include <sys/dsl_dataset.h> 44 #include <sys/dsl_dir.h> 45 #include <sys/dsl_pool.h> 46 #include <sys/dsl_synctask.h> 47 #include <sys/dsl_prop.h> 48 #include <sys/dmu_zfetch.h> 49 #include <sys/zfs_ioctl.h> 50 #include <sys/zap.h> 51 #include <sys/zio_checksum.h> 52 #include <sys/zio_compress.h> 53 #include <sys/sa.h> 54 #include <sys/zfeature.h> 55 #include <sys/abd.h> 56 #include <sys/brt.h> 57 #include <sys/trace_zfs.h> 58 #include <sys/zfs_racct.h> 59 #include <sys/zfs_rlock.h> 60 #ifdef _KERNEL 61 #include <sys/vmsystm.h> 62 #include <sys/zfs_znode.h> 63 #endif 64 65 /* 66 * Enable/disable nopwrite feature. 67 */ 68 static int zfs_nopwrite_enabled = 1; 69 70 /* 71 * Tunable to control percentage of dirtied L1 blocks from frees allowed into 72 * one TXG. After this threshold is crossed, additional dirty blocks from frees 73 * will wait until the next TXG. 74 * A value of zero will disable this throttle. 75 */ 76 static uint_t zfs_per_txg_dirty_frees_percent = 30; 77 78 /* 79 * Enable/disable forcing txg sync when dirty checking for holes with lseek(). 80 * By default this is enabled to ensure accurate hole reporting, it can result 81 * in a significant performance penalty for lseek(SEEK_HOLE) heavy workloads. 82 * Disabling this option will result in holes never being reported in dirty 83 * files which is always safe. 84 */ 85 static int zfs_dmu_offset_next_sync = 1; 86 87 /* 88 * Limit the amount we can prefetch with one call to this amount. This 89 * helps to limit the amount of memory that can be used by prefetching. 90 * Larger objects should be prefetched a bit at a time. 91 */ 92 #ifdef _ILP32 93 uint_t dmu_prefetch_max = 8 * 1024 * 1024; 94 #else 95 uint_t dmu_prefetch_max = 8 * SPA_MAXBLOCKSIZE; 96 #endif 97 98 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { 99 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "unallocated" }, 100 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "object directory" }, 101 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "object array" }, 102 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "packed nvlist" }, 103 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "packed nvlist size" }, 104 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj" }, 105 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj header" }, 106 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map header" }, 107 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map" }, 108 {DMU_BSWAP_UINT64, TRUE, FALSE, TRUE, "ZIL intent log" }, 109 {DMU_BSWAP_DNODE, TRUE, FALSE, TRUE, "DMU dnode" }, 110 {DMU_BSWAP_OBJSET, TRUE, TRUE, FALSE, "DMU objset" }, 111 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL directory" }, 112 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL directory child map"}, 113 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset snap map" }, 114 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL props" }, 115 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL dataset" }, 116 {DMU_BSWAP_ZNODE, TRUE, FALSE, FALSE, "ZFS znode" }, 117 {DMU_BSWAP_OLDACL, TRUE, FALSE, TRUE, "ZFS V0 ACL" }, 118 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "ZFS plain file" }, 119 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS directory" }, 120 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "ZFS master node" }, 121 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS delete queue" }, 122 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "zvol object" }, 123 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "zvol prop" }, 124 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "other uint8[]" }, 125 {DMU_BSWAP_UINT64, FALSE, FALSE, TRUE, "other uint64[]" }, 126 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "other ZAP" }, 127 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "persistent error log" }, 128 {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "SPA history" }, 129 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA history offsets" }, 130 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "Pool properties" }, 131 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL permissions" }, 132 {DMU_BSWAP_ACL, TRUE, FALSE, TRUE, "ZFS ACL" }, 133 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "ZFS SYSACL" }, 134 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "FUID table" }, 135 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "FUID table size" }, 136 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset next clones"}, 137 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan work queue" }, 138 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project used" }, 139 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project quota"}, 140 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "snapshot refcount tags"}, 141 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT ZAP algorithm" }, 142 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT statistics" }, 143 {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "System attributes" }, 144 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA master node" }, 145 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr registration" }, 146 {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr layouts" }, 147 {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan translations" }, 148 {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "deduplicated block" }, 149 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL deadlist map" }, 150 {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL deadlist map hdr" }, 151 {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dir clones" }, 152 {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj subobj" } 153 }; 154 155 dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = { 156 { byteswap_uint8_array, "uint8" }, 157 { byteswap_uint16_array, "uint16" }, 158 { byteswap_uint32_array, "uint32" }, 159 { byteswap_uint64_array, "uint64" }, 160 { zap_byteswap, "zap" }, 161 { dnode_buf_byteswap, "dnode" }, 162 { dmu_objset_byteswap, "objset" }, 163 { zfs_znode_byteswap, "znode" }, 164 { zfs_oldacl_byteswap, "oldacl" }, 165 { zfs_acl_byteswap, "acl" } 166 }; 167 168 int 169 dmu_buf_hold_noread_by_dnode(dnode_t *dn, uint64_t offset, 170 const void *tag, dmu_buf_t **dbp) 171 { 172 uint64_t blkid; 173 dmu_buf_impl_t *db; 174 175 rw_enter(&dn->dn_struct_rwlock, RW_READER); 176 blkid = dbuf_whichblock(dn, 0, offset); 177 db = dbuf_hold(dn, blkid, tag); 178 rw_exit(&dn->dn_struct_rwlock); 179 180 if (db == NULL) { 181 *dbp = NULL; 182 return (SET_ERROR(EIO)); 183 } 184 185 *dbp = &db->db; 186 return (0); 187 } 188 189 int 190 dmu_buf_hold_noread(objset_t *os, uint64_t object, uint64_t offset, 191 const void *tag, dmu_buf_t **dbp) 192 { 193 dnode_t *dn; 194 uint64_t blkid; 195 dmu_buf_impl_t *db; 196 int err; 197 198 err = dnode_hold(os, object, FTAG, &dn); 199 if (err) 200 return (err); 201 rw_enter(&dn->dn_struct_rwlock, RW_READER); 202 blkid = dbuf_whichblock(dn, 0, offset); 203 db = dbuf_hold(dn, blkid, tag); 204 rw_exit(&dn->dn_struct_rwlock); 205 dnode_rele(dn, FTAG); 206 207 if (db == NULL) { 208 *dbp = NULL; 209 return (SET_ERROR(EIO)); 210 } 211 212 *dbp = &db->db; 213 return (err); 214 } 215 216 int 217 dmu_buf_hold_by_dnode(dnode_t *dn, uint64_t offset, 218 const void *tag, dmu_buf_t **dbp, int flags) 219 { 220 int err; 221 int db_flags = DB_RF_CANFAIL; 222 223 if (flags & DMU_READ_NO_PREFETCH) 224 db_flags |= DB_RF_NOPREFETCH; 225 if (flags & DMU_READ_NO_DECRYPT) 226 db_flags |= DB_RF_NO_DECRYPT; 227 228 err = dmu_buf_hold_noread_by_dnode(dn, offset, tag, dbp); 229 if (err == 0) { 230 dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp); 231 err = dbuf_read(db, NULL, db_flags); 232 if (err != 0) { 233 dbuf_rele(db, tag); 234 *dbp = NULL; 235 } 236 } 237 238 return (err); 239 } 240 241 int 242 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 243 const void *tag, dmu_buf_t **dbp, int flags) 244 { 245 int err; 246 int db_flags = DB_RF_CANFAIL; 247 248 if (flags & DMU_READ_NO_PREFETCH) 249 db_flags |= DB_RF_NOPREFETCH; 250 if (flags & DMU_READ_NO_DECRYPT) 251 db_flags |= DB_RF_NO_DECRYPT; 252 253 err = dmu_buf_hold_noread(os, object, offset, tag, dbp); 254 if (err == 0) { 255 dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp); 256 err = dbuf_read(db, NULL, db_flags); 257 if (err != 0) { 258 dbuf_rele(db, tag); 259 *dbp = NULL; 260 } 261 } 262 263 return (err); 264 } 265 266 int 267 dmu_bonus_max(void) 268 { 269 return (DN_OLD_MAX_BONUSLEN); 270 } 271 272 int 273 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx) 274 { 275 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 276 dnode_t *dn; 277 int error; 278 279 DB_DNODE_ENTER(db); 280 dn = DB_DNODE(db); 281 282 if (dn->dn_bonus != db) { 283 error = SET_ERROR(EINVAL); 284 } else if (newsize < 0 || newsize > db_fake->db_size) { 285 error = SET_ERROR(EINVAL); 286 } else { 287 dnode_setbonuslen(dn, newsize, tx); 288 error = 0; 289 } 290 291 DB_DNODE_EXIT(db); 292 return (error); 293 } 294 295 int 296 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx) 297 { 298 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 299 dnode_t *dn; 300 int error; 301 302 DB_DNODE_ENTER(db); 303 dn = DB_DNODE(db); 304 305 if (!DMU_OT_IS_VALID(type)) { 306 error = SET_ERROR(EINVAL); 307 } else if (dn->dn_bonus != db) { 308 error = SET_ERROR(EINVAL); 309 } else { 310 dnode_setbonus_type(dn, type, tx); 311 error = 0; 312 } 313 314 DB_DNODE_EXIT(db); 315 return (error); 316 } 317 318 dmu_object_type_t 319 dmu_get_bonustype(dmu_buf_t *db_fake) 320 { 321 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 322 dnode_t *dn; 323 dmu_object_type_t type; 324 325 DB_DNODE_ENTER(db); 326 dn = DB_DNODE(db); 327 type = dn->dn_bonustype; 328 DB_DNODE_EXIT(db); 329 330 return (type); 331 } 332 333 int 334 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx) 335 { 336 dnode_t *dn; 337 int error; 338 339 error = dnode_hold(os, object, FTAG, &dn); 340 dbuf_rm_spill(dn, tx); 341 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 342 dnode_rm_spill(dn, tx); 343 rw_exit(&dn->dn_struct_rwlock); 344 dnode_rele(dn, FTAG); 345 return (error); 346 } 347 348 /* 349 * Lookup and hold the bonus buffer for the provided dnode. If the dnode 350 * has not yet been allocated a new bonus dbuf a will be allocated. 351 * Returns ENOENT, EIO, or 0. 352 */ 353 int dmu_bonus_hold_by_dnode(dnode_t *dn, const void *tag, dmu_buf_t **dbp, 354 uint32_t flags) 355 { 356 dmu_buf_impl_t *db; 357 int error; 358 uint32_t db_flags = DB_RF_MUST_SUCCEED; 359 360 if (flags & DMU_READ_NO_PREFETCH) 361 db_flags |= DB_RF_NOPREFETCH; 362 if (flags & DMU_READ_NO_DECRYPT) 363 db_flags |= DB_RF_NO_DECRYPT; 364 365 rw_enter(&dn->dn_struct_rwlock, RW_READER); 366 if (dn->dn_bonus == NULL) { 367 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 368 rw_exit(&dn->dn_struct_rwlock); 369 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 370 } 371 if (dn->dn_bonus == NULL) 372 dbuf_create_bonus(dn); 373 } 374 db = dn->dn_bonus; 375 376 /* as long as the bonus buf is held, the dnode will be held */ 377 if (zfs_refcount_add(&db->db_holds, tag) == 1) { 378 VERIFY(dnode_add_ref(dn, db)); 379 atomic_inc_32(&dn->dn_dbufs_count); 380 } 381 382 /* 383 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's 384 * hold and incrementing the dbuf count to ensure that dnode_move() sees 385 * a dnode hold for every dbuf. 386 */ 387 rw_exit(&dn->dn_struct_rwlock); 388 389 error = dbuf_read(db, NULL, db_flags); 390 if (error) { 391 dnode_evict_bonus(dn); 392 dbuf_rele(db, tag); 393 *dbp = NULL; 394 return (error); 395 } 396 397 *dbp = &db->db; 398 return (0); 399 } 400 401 int 402 dmu_bonus_hold(objset_t *os, uint64_t object, const void *tag, dmu_buf_t **dbp) 403 { 404 dnode_t *dn; 405 int error; 406 407 error = dnode_hold(os, object, FTAG, &dn); 408 if (error) 409 return (error); 410 411 error = dmu_bonus_hold_by_dnode(dn, tag, dbp, DMU_READ_NO_PREFETCH); 412 dnode_rele(dn, FTAG); 413 414 return (error); 415 } 416 417 /* 418 * returns ENOENT, EIO, or 0. 419 * 420 * This interface will allocate a blank spill dbuf when a spill blk 421 * doesn't already exist on the dnode. 422 * 423 * if you only want to find an already existing spill db, then 424 * dmu_spill_hold_existing() should be used. 425 */ 426 int 427 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, const void *tag, 428 dmu_buf_t **dbp) 429 { 430 dmu_buf_impl_t *db = NULL; 431 int err; 432 433 if ((flags & DB_RF_HAVESTRUCT) == 0) 434 rw_enter(&dn->dn_struct_rwlock, RW_READER); 435 436 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag); 437 438 if ((flags & DB_RF_HAVESTRUCT) == 0) 439 rw_exit(&dn->dn_struct_rwlock); 440 441 if (db == NULL) { 442 *dbp = NULL; 443 return (SET_ERROR(EIO)); 444 } 445 err = dbuf_read(db, NULL, flags); 446 if (err == 0) 447 *dbp = &db->db; 448 else { 449 dbuf_rele(db, tag); 450 *dbp = NULL; 451 } 452 return (err); 453 } 454 455 int 456 dmu_spill_hold_existing(dmu_buf_t *bonus, const void *tag, dmu_buf_t **dbp) 457 { 458 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 459 dnode_t *dn; 460 int err; 461 462 DB_DNODE_ENTER(db); 463 dn = DB_DNODE(db); 464 465 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) { 466 err = SET_ERROR(EINVAL); 467 } else { 468 rw_enter(&dn->dn_struct_rwlock, RW_READER); 469 470 if (!dn->dn_have_spill) { 471 err = SET_ERROR(ENOENT); 472 } else { 473 err = dmu_spill_hold_by_dnode(dn, 474 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp); 475 } 476 477 rw_exit(&dn->dn_struct_rwlock); 478 } 479 480 DB_DNODE_EXIT(db); 481 return (err); 482 } 483 484 int 485 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, uint32_t flags, const void *tag, 486 dmu_buf_t **dbp) 487 { 488 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 489 dnode_t *dn; 490 int err; 491 uint32_t db_flags = DB_RF_CANFAIL; 492 493 if (flags & DMU_READ_NO_DECRYPT) 494 db_flags |= DB_RF_NO_DECRYPT; 495 496 DB_DNODE_ENTER(db); 497 dn = DB_DNODE(db); 498 err = dmu_spill_hold_by_dnode(dn, db_flags, tag, dbp); 499 DB_DNODE_EXIT(db); 500 501 return (err); 502 } 503 504 /* 505 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 506 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 507 * and can induce severe lock contention when writing to several files 508 * whose dnodes are in the same block. 509 */ 510 int 511 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, 512 boolean_t read, const void *tag, int *numbufsp, dmu_buf_t ***dbpp, 513 uint32_t flags) 514 { 515 dmu_buf_t **dbp; 516 zstream_t *zs = NULL; 517 uint64_t blkid, nblks, i; 518 uint32_t dbuf_flags; 519 int err; 520 zio_t *zio = NULL; 521 boolean_t missed = B_FALSE; 522 523 ASSERT(!read || length <= DMU_MAX_ACCESS); 524 525 /* 526 * Note: We directly notify the prefetch code of this read, so that 527 * we can tell it about the multi-block read. dbuf_read() only knows 528 * about the one block it is accessing. 529 */ 530 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT | 531 DB_RF_NOPREFETCH; 532 533 if ((flags & DMU_READ_NO_DECRYPT) != 0) 534 dbuf_flags |= DB_RF_NO_DECRYPT; 535 536 rw_enter(&dn->dn_struct_rwlock, RW_READER); 537 if (dn->dn_datablkshift) { 538 int blkshift = dn->dn_datablkshift; 539 nblks = (P2ROUNDUP(offset + length, 1ULL << blkshift) - 540 P2ALIGN(offset, 1ULL << blkshift)) >> blkshift; 541 } else { 542 if (offset + length > dn->dn_datablksz) { 543 zfs_panic_recover("zfs: accessing past end of object " 544 "%llx/%llx (size=%u access=%llu+%llu)", 545 (longlong_t)dn->dn_objset-> 546 os_dsl_dataset->ds_object, 547 (longlong_t)dn->dn_object, dn->dn_datablksz, 548 (longlong_t)offset, (longlong_t)length); 549 rw_exit(&dn->dn_struct_rwlock); 550 return (SET_ERROR(EIO)); 551 } 552 nblks = 1; 553 } 554 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 555 556 if (read) 557 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, 558 ZIO_FLAG_CANFAIL); 559 blkid = dbuf_whichblock(dn, 0, offset); 560 if ((flags & DMU_READ_NO_PREFETCH) == 0) { 561 /* 562 * Prepare the zfetch before initiating the demand reads, so 563 * that if multiple threads block on same indirect block, we 564 * base predictions on the original less racy request order. 565 */ 566 zs = dmu_zfetch_prepare(&dn->dn_zfetch, blkid, nblks, read, 567 B_TRUE); 568 } 569 for (i = 0; i < nblks; i++) { 570 dmu_buf_impl_t *db = dbuf_hold(dn, blkid + i, tag); 571 if (db == NULL) { 572 if (zs) 573 dmu_zfetch_run(zs, missed, B_TRUE); 574 rw_exit(&dn->dn_struct_rwlock); 575 dmu_buf_rele_array(dbp, nblks, tag); 576 if (read) 577 zio_nowait(zio); 578 return (SET_ERROR(EIO)); 579 } 580 581 /* 582 * Initiate async demand data read. 583 * We check the db_state after calling dbuf_read() because 584 * (1) dbuf_read() may change the state to CACHED due to a 585 * hit in the ARC, and (2) on a cache miss, a child will 586 * have been added to "zio" but not yet completed, so the 587 * state will not yet be CACHED. 588 */ 589 if (read) { 590 if (i == nblks - 1 && blkid + i < dn->dn_maxblkid && 591 offset + length < db->db.db_offset + 592 db->db.db_size) { 593 if (offset <= db->db.db_offset) 594 dbuf_flags |= DB_RF_PARTIAL_FIRST; 595 else 596 dbuf_flags |= DB_RF_PARTIAL_MORE; 597 } 598 (void) dbuf_read(db, zio, dbuf_flags); 599 if (db->db_state != DB_CACHED) 600 missed = B_TRUE; 601 } 602 dbp[i] = &db->db; 603 } 604 605 if (!read) 606 zfs_racct_write(length, nblks); 607 608 if (zs) 609 dmu_zfetch_run(zs, missed, B_TRUE); 610 rw_exit(&dn->dn_struct_rwlock); 611 612 if (read) { 613 /* wait for async read i/o */ 614 err = zio_wait(zio); 615 if (err) { 616 dmu_buf_rele_array(dbp, nblks, tag); 617 return (err); 618 } 619 620 /* wait for other io to complete */ 621 for (i = 0; i < nblks; i++) { 622 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 623 mutex_enter(&db->db_mtx); 624 while (db->db_state == DB_READ || 625 db->db_state == DB_FILL) 626 cv_wait(&db->db_changed, &db->db_mtx); 627 if (db->db_state == DB_UNCACHED) 628 err = SET_ERROR(EIO); 629 mutex_exit(&db->db_mtx); 630 if (err) { 631 dmu_buf_rele_array(dbp, nblks, tag); 632 return (err); 633 } 634 } 635 } 636 637 *numbufsp = nblks; 638 *dbpp = dbp; 639 return (0); 640 } 641 642 int 643 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 644 uint64_t length, int read, const void *tag, int *numbufsp, 645 dmu_buf_t ***dbpp) 646 { 647 dnode_t *dn; 648 int err; 649 650 err = dnode_hold(os, object, FTAG, &dn); 651 if (err) 652 return (err); 653 654 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 655 numbufsp, dbpp, DMU_READ_PREFETCH); 656 657 dnode_rele(dn, FTAG); 658 659 return (err); 660 } 661 662 int 663 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset, 664 uint64_t length, boolean_t read, const void *tag, int *numbufsp, 665 dmu_buf_t ***dbpp) 666 { 667 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 668 dnode_t *dn; 669 int err; 670 671 DB_DNODE_ENTER(db); 672 dn = DB_DNODE(db); 673 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 674 numbufsp, dbpp, DMU_READ_PREFETCH); 675 DB_DNODE_EXIT(db); 676 677 return (err); 678 } 679 680 void 681 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, const void *tag) 682 { 683 int i; 684 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 685 686 if (numbufs == 0) 687 return; 688 689 for (i = 0; i < numbufs; i++) { 690 if (dbp[i]) 691 dbuf_rele(dbp[i], tag); 692 } 693 694 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 695 } 696 697 /* 698 * Issue prefetch I/Os for the given blocks. If level is greater than 0, the 699 * indirect blocks prefetched will be those that point to the blocks containing 700 * the data starting at offset, and continuing to offset + len. If the range 701 * it too long, prefetch the first dmu_prefetch_max bytes as requested, while 702 * for the rest only a higher level, also fitting within dmu_prefetch_max. It 703 * should primarily help random reads, since for long sequential reads there is 704 * a speculative prefetcher. 705 * 706 * Note that if the indirect blocks above the blocks being prefetched are not 707 * in cache, they will be asynchronously read in. Dnode read by dnode_hold() 708 * is currently synchronous. 709 */ 710 void 711 dmu_prefetch(objset_t *os, uint64_t object, int64_t level, uint64_t offset, 712 uint64_t len, zio_priority_t pri) 713 { 714 dnode_t *dn; 715 716 if (dmu_prefetch_max == 0 || len == 0) { 717 dmu_prefetch_dnode(os, object, pri); 718 return; 719 } 720 721 if (dnode_hold(os, object, FTAG, &dn) != 0) 722 return; 723 724 dmu_prefetch_by_dnode(dn, level, offset, len, pri); 725 726 dnode_rele(dn, FTAG); 727 } 728 729 void 730 dmu_prefetch_by_dnode(dnode_t *dn, int64_t level, uint64_t offset, 731 uint64_t len, zio_priority_t pri) 732 { 733 int64_t level2 = level; 734 uint64_t start, end, start2, end2; 735 736 /* 737 * Depending on len we may do two prefetches: blocks [start, end) at 738 * level, and following blocks [start2, end2) at higher level2. 739 */ 740 rw_enter(&dn->dn_struct_rwlock, RW_READER); 741 if (dn->dn_datablkshift != 0) { 742 /* 743 * The object has multiple blocks. Calculate the full range 744 * of blocks [start, end2) and then split it into two parts, 745 * so that the first [start, end) fits into dmu_prefetch_max. 746 */ 747 start = dbuf_whichblock(dn, level, offset); 748 end2 = dbuf_whichblock(dn, level, offset + len - 1) + 1; 749 uint8_t ibs = dn->dn_indblkshift; 750 uint8_t bs = (level == 0) ? dn->dn_datablkshift : ibs; 751 uint_t limit = P2ROUNDUP(dmu_prefetch_max, 1 << bs) >> bs; 752 start2 = end = MIN(end2, start + limit); 753 754 /* 755 * Find level2 where [start2, end2) fits into dmu_prefetch_max. 756 */ 757 uint8_t ibps = ibs - SPA_BLKPTRSHIFT; 758 limit = P2ROUNDUP(dmu_prefetch_max, 1 << ibs) >> ibs; 759 do { 760 level2++; 761 start2 = P2ROUNDUP(start2, 1 << ibps) >> ibps; 762 end2 = P2ROUNDUP(end2, 1 << ibps) >> ibps; 763 } while (end2 - start2 > limit); 764 } else { 765 /* There is only one block. Prefetch it or nothing. */ 766 start = start2 = end2 = 0; 767 end = start + (level == 0 && offset < dn->dn_datablksz); 768 } 769 770 for (uint64_t i = start; i < end; i++) 771 dbuf_prefetch(dn, level, i, pri, 0); 772 for (uint64_t i = start2; i < end2; i++) 773 dbuf_prefetch(dn, level2, i, pri, 0); 774 rw_exit(&dn->dn_struct_rwlock); 775 } 776 777 /* 778 * Issue prefetch I/Os for the given object's dnode. 779 */ 780 void 781 dmu_prefetch_dnode(objset_t *os, uint64_t object, zio_priority_t pri) 782 { 783 if (object == 0 || object >= DN_MAX_OBJECT) 784 return; 785 786 dnode_t *dn = DMU_META_DNODE(os); 787 rw_enter(&dn->dn_struct_rwlock, RW_READER); 788 uint64_t blkid = dbuf_whichblock(dn, 0, object * sizeof (dnode_phys_t)); 789 dbuf_prefetch(dn, 0, blkid, pri, 0); 790 rw_exit(&dn->dn_struct_rwlock); 791 } 792 793 /* 794 * Get the next "chunk" of file data to free. We traverse the file from 795 * the end so that the file gets shorter over time (if we crashes in the 796 * middle, this will leave us in a better state). We find allocated file 797 * data by simply searching the allocated level 1 indirects. 798 * 799 * On input, *start should be the first offset that does not need to be 800 * freed (e.g. "offset + length"). On return, *start will be the first 801 * offset that should be freed and l1blks is set to the number of level 1 802 * indirect blocks found within the chunk. 803 */ 804 static int 805 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum, uint64_t *l1blks) 806 { 807 uint64_t blks; 808 uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1); 809 /* bytes of data covered by a level-1 indirect block */ 810 uint64_t iblkrange = (uint64_t)dn->dn_datablksz * 811 EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 812 813 ASSERT3U(minimum, <=, *start); 814 815 /* 816 * Check if we can free the entire range assuming that all of the 817 * L1 blocks in this range have data. If we can, we use this 818 * worst case value as an estimate so we can avoid having to look 819 * at the object's actual data. 820 */ 821 uint64_t total_l1blks = 822 (roundup(*start, iblkrange) - (minimum / iblkrange * iblkrange)) / 823 iblkrange; 824 if (total_l1blks <= maxblks) { 825 *l1blks = total_l1blks; 826 *start = minimum; 827 return (0); 828 } 829 ASSERT(ISP2(iblkrange)); 830 831 for (blks = 0; *start > minimum && blks < maxblks; blks++) { 832 int err; 833 834 /* 835 * dnode_next_offset(BACKWARDS) will find an allocated L1 836 * indirect block at or before the input offset. We must 837 * decrement *start so that it is at the end of the region 838 * to search. 839 */ 840 (*start)--; 841 842 err = dnode_next_offset(dn, 843 DNODE_FIND_BACKWARDS, start, 2, 1, 0); 844 845 /* if there are no indirect blocks before start, we are done */ 846 if (err == ESRCH) { 847 *start = minimum; 848 break; 849 } else if (err != 0) { 850 *l1blks = blks; 851 return (err); 852 } 853 854 /* set start to the beginning of this L1 indirect */ 855 *start = P2ALIGN(*start, iblkrange); 856 } 857 if (*start < minimum) 858 *start = minimum; 859 *l1blks = blks; 860 861 return (0); 862 } 863 864 /* 865 * If this objset is of type OST_ZFS return true if vfs's unmounted flag is set, 866 * otherwise return false. 867 * Used below in dmu_free_long_range_impl() to enable abort when unmounting 868 */ 869 static boolean_t 870 dmu_objset_zfs_unmounting(objset_t *os) 871 { 872 #ifdef _KERNEL 873 if (dmu_objset_type(os) == DMU_OST_ZFS) 874 return (zfs_get_vfs_flag_unmounted(os)); 875 #else 876 (void) os; 877 #endif 878 return (B_FALSE); 879 } 880 881 static int 882 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 883 uint64_t length) 884 { 885 uint64_t object_size; 886 int err; 887 uint64_t dirty_frees_threshold; 888 dsl_pool_t *dp = dmu_objset_pool(os); 889 890 if (dn == NULL) 891 return (SET_ERROR(EINVAL)); 892 893 object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 894 if (offset >= object_size) 895 return (0); 896 897 if (zfs_per_txg_dirty_frees_percent <= 100) 898 dirty_frees_threshold = 899 zfs_per_txg_dirty_frees_percent * zfs_dirty_data_max / 100; 900 else 901 dirty_frees_threshold = zfs_dirty_data_max / 20; 902 903 if (length == DMU_OBJECT_END || offset + length > object_size) 904 length = object_size - offset; 905 906 while (length != 0) { 907 uint64_t chunk_end, chunk_begin, chunk_len; 908 uint64_t l1blks; 909 dmu_tx_t *tx; 910 911 if (dmu_objset_zfs_unmounting(dn->dn_objset)) 912 return (SET_ERROR(EINTR)); 913 914 chunk_end = chunk_begin = offset + length; 915 916 /* move chunk_begin backwards to the beginning of this chunk */ 917 err = get_next_chunk(dn, &chunk_begin, offset, &l1blks); 918 if (err) 919 return (err); 920 ASSERT3U(chunk_begin, >=, offset); 921 ASSERT3U(chunk_begin, <=, chunk_end); 922 923 chunk_len = chunk_end - chunk_begin; 924 925 tx = dmu_tx_create(os); 926 dmu_tx_hold_free(tx, dn->dn_object, chunk_begin, chunk_len); 927 928 /* 929 * Mark this transaction as typically resulting in a net 930 * reduction in space used. 931 */ 932 dmu_tx_mark_netfree(tx); 933 err = dmu_tx_assign(tx, TXG_WAIT); 934 if (err) { 935 dmu_tx_abort(tx); 936 return (err); 937 } 938 939 uint64_t txg = dmu_tx_get_txg(tx); 940 941 mutex_enter(&dp->dp_lock); 942 uint64_t long_free_dirty = 943 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK]; 944 mutex_exit(&dp->dp_lock); 945 946 /* 947 * To avoid filling up a TXG with just frees, wait for 948 * the next TXG to open before freeing more chunks if 949 * we have reached the threshold of frees. 950 */ 951 if (dirty_frees_threshold != 0 && 952 long_free_dirty >= dirty_frees_threshold) { 953 DMU_TX_STAT_BUMP(dmu_tx_dirty_frees_delay); 954 dmu_tx_commit(tx); 955 txg_wait_open(dp, 0, B_TRUE); 956 continue; 957 } 958 959 /* 960 * In order to prevent unnecessary write throttling, for each 961 * TXG, we track the cumulative size of L1 blocks being dirtied 962 * in dnode_free_range() below. We compare this number to a 963 * tunable threshold, past which we prevent new L1 dirty freeing 964 * blocks from being added into the open TXG. See 965 * dmu_free_long_range_impl() for details. The threshold 966 * prevents write throttle activation due to dirty freeing L1 967 * blocks taking up a large percentage of zfs_dirty_data_max. 968 */ 969 mutex_enter(&dp->dp_lock); 970 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] += 971 l1blks << dn->dn_indblkshift; 972 mutex_exit(&dp->dp_lock); 973 DTRACE_PROBE3(free__long__range, 974 uint64_t, long_free_dirty, uint64_t, chunk_len, 975 uint64_t, txg); 976 dnode_free_range(dn, chunk_begin, chunk_len, tx); 977 978 dmu_tx_commit(tx); 979 980 length -= chunk_len; 981 } 982 return (0); 983 } 984 985 int 986 dmu_free_long_range(objset_t *os, uint64_t object, 987 uint64_t offset, uint64_t length) 988 { 989 dnode_t *dn; 990 int err; 991 992 err = dnode_hold(os, object, FTAG, &dn); 993 if (err != 0) 994 return (err); 995 err = dmu_free_long_range_impl(os, dn, offset, length); 996 997 /* 998 * It is important to zero out the maxblkid when freeing the entire 999 * file, so that (a) subsequent calls to dmu_free_long_range_impl() 1000 * will take the fast path, and (b) dnode_reallocate() can verify 1001 * that the entire file has been freed. 1002 */ 1003 if (err == 0 && offset == 0 && length == DMU_OBJECT_END) 1004 dn->dn_maxblkid = 0; 1005 1006 dnode_rele(dn, FTAG); 1007 return (err); 1008 } 1009 1010 int 1011 dmu_free_long_object(objset_t *os, uint64_t object) 1012 { 1013 dmu_tx_t *tx; 1014 int err; 1015 1016 err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END); 1017 if (err != 0) 1018 return (err); 1019 1020 tx = dmu_tx_create(os); 1021 dmu_tx_hold_bonus(tx, object); 1022 dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END); 1023 dmu_tx_mark_netfree(tx); 1024 err = dmu_tx_assign(tx, TXG_WAIT); 1025 if (err == 0) { 1026 err = dmu_object_free(os, object, tx); 1027 dmu_tx_commit(tx); 1028 } else { 1029 dmu_tx_abort(tx); 1030 } 1031 1032 return (err); 1033 } 1034 1035 int 1036 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 1037 uint64_t size, dmu_tx_t *tx) 1038 { 1039 dnode_t *dn; 1040 int err = dnode_hold(os, object, FTAG, &dn); 1041 if (err) 1042 return (err); 1043 ASSERT(offset < UINT64_MAX); 1044 ASSERT(size == DMU_OBJECT_END || size <= UINT64_MAX - offset); 1045 dnode_free_range(dn, offset, size, tx); 1046 dnode_rele(dn, FTAG); 1047 return (0); 1048 } 1049 1050 static int 1051 dmu_read_impl(dnode_t *dn, uint64_t offset, uint64_t size, 1052 void *buf, uint32_t flags) 1053 { 1054 dmu_buf_t **dbp; 1055 int numbufs, err = 0; 1056 1057 /* 1058 * Deal with odd block sizes, where there can't be data past the first 1059 * block. If we ever do the tail block optimization, we will need to 1060 * handle that here as well. 1061 */ 1062 if (dn->dn_maxblkid == 0) { 1063 uint64_t newsz = offset > dn->dn_datablksz ? 0 : 1064 MIN(size, dn->dn_datablksz - offset); 1065 memset((char *)buf + newsz, 0, size - newsz); 1066 size = newsz; 1067 } 1068 1069 while (size > 0) { 1070 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 1071 int i; 1072 1073 /* 1074 * NB: we could do this block-at-a-time, but it's nice 1075 * to be reading in parallel. 1076 */ 1077 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 1078 TRUE, FTAG, &numbufs, &dbp, flags); 1079 if (err) 1080 break; 1081 1082 for (i = 0; i < numbufs; i++) { 1083 uint64_t tocpy; 1084 int64_t bufoff; 1085 dmu_buf_t *db = dbp[i]; 1086 1087 ASSERT(size > 0); 1088 1089 bufoff = offset - db->db_offset; 1090 tocpy = MIN(db->db_size - bufoff, size); 1091 1092 (void) memcpy(buf, (char *)db->db_data + bufoff, tocpy); 1093 1094 offset += tocpy; 1095 size -= tocpy; 1096 buf = (char *)buf + tocpy; 1097 } 1098 dmu_buf_rele_array(dbp, numbufs, FTAG); 1099 } 1100 return (err); 1101 } 1102 1103 int 1104 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1105 void *buf, uint32_t flags) 1106 { 1107 dnode_t *dn; 1108 int err; 1109 1110 err = dnode_hold(os, object, FTAG, &dn); 1111 if (err != 0) 1112 return (err); 1113 1114 err = dmu_read_impl(dn, offset, size, buf, flags); 1115 dnode_rele(dn, FTAG); 1116 return (err); 1117 } 1118 1119 int 1120 dmu_read_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, void *buf, 1121 uint32_t flags) 1122 { 1123 return (dmu_read_impl(dn, offset, size, buf, flags)); 1124 } 1125 1126 static void 1127 dmu_write_impl(dmu_buf_t **dbp, int numbufs, uint64_t offset, uint64_t size, 1128 const void *buf, dmu_tx_t *tx) 1129 { 1130 int i; 1131 1132 for (i = 0; i < numbufs; i++) { 1133 uint64_t tocpy; 1134 int64_t bufoff; 1135 dmu_buf_t *db = dbp[i]; 1136 1137 ASSERT(size > 0); 1138 1139 bufoff = offset - db->db_offset; 1140 tocpy = MIN(db->db_size - bufoff, size); 1141 1142 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1143 1144 if (tocpy == db->db_size) 1145 dmu_buf_will_fill(db, tx, B_FALSE); 1146 else 1147 dmu_buf_will_dirty(db, tx); 1148 1149 (void) memcpy((char *)db->db_data + bufoff, buf, tocpy); 1150 1151 if (tocpy == db->db_size) 1152 dmu_buf_fill_done(db, tx, B_FALSE); 1153 1154 offset += tocpy; 1155 size -= tocpy; 1156 buf = (char *)buf + tocpy; 1157 } 1158 } 1159 1160 void 1161 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1162 const void *buf, dmu_tx_t *tx) 1163 { 1164 dmu_buf_t **dbp; 1165 int numbufs; 1166 1167 if (size == 0) 1168 return; 1169 1170 VERIFY0(dmu_buf_hold_array(os, object, offset, size, 1171 FALSE, FTAG, &numbufs, &dbp)); 1172 dmu_write_impl(dbp, numbufs, offset, size, buf, tx); 1173 dmu_buf_rele_array(dbp, numbufs, FTAG); 1174 } 1175 1176 /* 1177 * Note: Lustre is an external consumer of this interface. 1178 */ 1179 void 1180 dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, 1181 const void *buf, dmu_tx_t *tx) 1182 { 1183 dmu_buf_t **dbp; 1184 int numbufs; 1185 1186 if (size == 0) 1187 return; 1188 1189 VERIFY0(dmu_buf_hold_array_by_dnode(dn, offset, size, 1190 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH)); 1191 dmu_write_impl(dbp, numbufs, offset, size, buf, tx); 1192 dmu_buf_rele_array(dbp, numbufs, FTAG); 1193 } 1194 1195 void 1196 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1197 dmu_tx_t *tx) 1198 { 1199 dmu_buf_t **dbp; 1200 int numbufs, i; 1201 1202 if (size == 0) 1203 return; 1204 1205 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 1206 FALSE, FTAG, &numbufs, &dbp)); 1207 1208 for (i = 0; i < numbufs; i++) { 1209 dmu_buf_t *db = dbp[i]; 1210 1211 dmu_buf_will_not_fill(db, tx); 1212 } 1213 dmu_buf_rele_array(dbp, numbufs, FTAG); 1214 } 1215 1216 void 1217 dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset, 1218 void *data, uint8_t etype, uint8_t comp, int uncompressed_size, 1219 int compressed_size, int byteorder, dmu_tx_t *tx) 1220 { 1221 dmu_buf_t *db; 1222 1223 ASSERT3U(etype, <, NUM_BP_EMBEDDED_TYPES); 1224 ASSERT3U(comp, <, ZIO_COMPRESS_FUNCTIONS); 1225 VERIFY0(dmu_buf_hold_noread(os, object, offset, 1226 FTAG, &db)); 1227 1228 dmu_buf_write_embedded(db, 1229 data, (bp_embedded_type_t)etype, (enum zio_compress)comp, 1230 uncompressed_size, compressed_size, byteorder, tx); 1231 1232 dmu_buf_rele(db, FTAG); 1233 } 1234 1235 void 1236 dmu_redact(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1237 dmu_tx_t *tx) 1238 { 1239 int numbufs, i; 1240 dmu_buf_t **dbp; 1241 1242 VERIFY0(dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, 1243 &numbufs, &dbp)); 1244 for (i = 0; i < numbufs; i++) 1245 dmu_buf_redact(dbp[i], tx); 1246 dmu_buf_rele_array(dbp, numbufs, FTAG); 1247 } 1248 1249 #ifdef _KERNEL 1250 int 1251 dmu_read_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size) 1252 { 1253 dmu_buf_t **dbp; 1254 int numbufs, i, err; 1255 1256 /* 1257 * NB: we could do this block-at-a-time, but it's nice 1258 * to be reading in parallel. 1259 */ 1260 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, 1261 TRUE, FTAG, &numbufs, &dbp, 0); 1262 if (err) 1263 return (err); 1264 1265 for (i = 0; i < numbufs; i++) { 1266 uint64_t tocpy; 1267 int64_t bufoff; 1268 dmu_buf_t *db = dbp[i]; 1269 1270 ASSERT(size > 0); 1271 1272 bufoff = zfs_uio_offset(uio) - db->db_offset; 1273 tocpy = MIN(db->db_size - bufoff, size); 1274 1275 err = zfs_uio_fault_move((char *)db->db_data + bufoff, tocpy, 1276 UIO_READ, uio); 1277 1278 if (err) 1279 break; 1280 1281 size -= tocpy; 1282 } 1283 dmu_buf_rele_array(dbp, numbufs, FTAG); 1284 1285 return (err); 1286 } 1287 1288 /* 1289 * Read 'size' bytes into the uio buffer. 1290 * From object zdb->db_object. 1291 * Starting at zfs_uio_offset(uio). 1292 * 1293 * If the caller already has a dbuf in the target object 1294 * (e.g. its bonus buffer), this routine is faster than dmu_read_uio(), 1295 * because we don't have to find the dnode_t for the object. 1296 */ 1297 int 1298 dmu_read_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size) 1299 { 1300 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1301 dnode_t *dn; 1302 int err; 1303 1304 if (size == 0) 1305 return (0); 1306 1307 DB_DNODE_ENTER(db); 1308 dn = DB_DNODE(db); 1309 err = dmu_read_uio_dnode(dn, uio, size); 1310 DB_DNODE_EXIT(db); 1311 1312 return (err); 1313 } 1314 1315 /* 1316 * Read 'size' bytes into the uio buffer. 1317 * From the specified object 1318 * Starting at offset zfs_uio_offset(uio). 1319 */ 1320 int 1321 dmu_read_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size) 1322 { 1323 dnode_t *dn; 1324 int err; 1325 1326 if (size == 0) 1327 return (0); 1328 1329 err = dnode_hold(os, object, FTAG, &dn); 1330 if (err) 1331 return (err); 1332 1333 err = dmu_read_uio_dnode(dn, uio, size); 1334 1335 dnode_rele(dn, FTAG); 1336 1337 return (err); 1338 } 1339 1340 int 1341 dmu_write_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx) 1342 { 1343 dmu_buf_t **dbp; 1344 int numbufs; 1345 int err = 0; 1346 int i; 1347 1348 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, 1349 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH); 1350 if (err) 1351 return (err); 1352 1353 for (i = 0; i < numbufs; i++) { 1354 uint64_t tocpy; 1355 int64_t bufoff; 1356 dmu_buf_t *db = dbp[i]; 1357 1358 ASSERT(size > 0); 1359 1360 offset_t off = zfs_uio_offset(uio); 1361 bufoff = off - db->db_offset; 1362 tocpy = MIN(db->db_size - bufoff, size); 1363 1364 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1365 1366 if (tocpy == db->db_size) 1367 dmu_buf_will_fill(db, tx, B_TRUE); 1368 else 1369 dmu_buf_will_dirty(db, tx); 1370 1371 err = zfs_uio_fault_move((char *)db->db_data + bufoff, 1372 tocpy, UIO_WRITE, uio); 1373 1374 if (tocpy == db->db_size && dmu_buf_fill_done(db, tx, err)) { 1375 /* The fill was reverted. Undo any uio progress. */ 1376 zfs_uio_advance(uio, off - zfs_uio_offset(uio)); 1377 } 1378 1379 if (err) 1380 break; 1381 1382 size -= tocpy; 1383 } 1384 1385 dmu_buf_rele_array(dbp, numbufs, FTAG); 1386 return (err); 1387 } 1388 1389 /* 1390 * Write 'size' bytes from the uio buffer. 1391 * To object zdb->db_object. 1392 * Starting at offset zfs_uio_offset(uio). 1393 * 1394 * If the caller already has a dbuf in the target object 1395 * (e.g. its bonus buffer), this routine is faster than dmu_write_uio(), 1396 * because we don't have to find the dnode_t for the object. 1397 */ 1398 int 1399 dmu_write_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size, 1400 dmu_tx_t *tx) 1401 { 1402 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1403 dnode_t *dn; 1404 int err; 1405 1406 if (size == 0) 1407 return (0); 1408 1409 DB_DNODE_ENTER(db); 1410 dn = DB_DNODE(db); 1411 err = dmu_write_uio_dnode(dn, uio, size, tx); 1412 DB_DNODE_EXIT(db); 1413 1414 return (err); 1415 } 1416 1417 /* 1418 * Write 'size' bytes from the uio buffer. 1419 * To the specified object. 1420 * Starting at offset zfs_uio_offset(uio). 1421 */ 1422 int 1423 dmu_write_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size, 1424 dmu_tx_t *tx) 1425 { 1426 dnode_t *dn; 1427 int err; 1428 1429 if (size == 0) 1430 return (0); 1431 1432 err = dnode_hold(os, object, FTAG, &dn); 1433 if (err) 1434 return (err); 1435 1436 err = dmu_write_uio_dnode(dn, uio, size, tx); 1437 1438 dnode_rele(dn, FTAG); 1439 1440 return (err); 1441 } 1442 #endif /* _KERNEL */ 1443 1444 /* 1445 * Allocate a loaned anonymous arc buffer. 1446 */ 1447 arc_buf_t * 1448 dmu_request_arcbuf(dmu_buf_t *handle, int size) 1449 { 1450 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle; 1451 1452 return (arc_loan_buf(db->db_objset->os_spa, B_FALSE, size)); 1453 } 1454 1455 /* 1456 * Free a loaned arc buffer. 1457 */ 1458 void 1459 dmu_return_arcbuf(arc_buf_t *buf) 1460 { 1461 arc_return_buf(buf, FTAG); 1462 arc_buf_destroy(buf, FTAG); 1463 } 1464 1465 /* 1466 * A "lightweight" write is faster than a regular write (e.g. 1467 * dmu_write_by_dnode() or dmu_assign_arcbuf_by_dnode()), because it avoids the 1468 * CPU cost of creating a dmu_buf_impl_t and arc_buf_[hdr_]_t. However, the 1469 * data can not be read or overwritten until the transaction's txg has been 1470 * synced. This makes it appropriate for workloads that are known to be 1471 * (temporarily) write-only, like "zfs receive". 1472 * 1473 * A single block is written, starting at the specified offset in bytes. If 1474 * the call is successful, it returns 0 and the provided abd has been 1475 * consumed (the caller should not free it). 1476 */ 1477 int 1478 dmu_lightweight_write_by_dnode(dnode_t *dn, uint64_t offset, abd_t *abd, 1479 const zio_prop_t *zp, zio_flag_t flags, dmu_tx_t *tx) 1480 { 1481 dbuf_dirty_record_t *dr = 1482 dbuf_dirty_lightweight(dn, dbuf_whichblock(dn, 0, offset), tx); 1483 if (dr == NULL) 1484 return (SET_ERROR(EIO)); 1485 dr->dt.dll.dr_abd = abd; 1486 dr->dt.dll.dr_props = *zp; 1487 dr->dt.dll.dr_flags = flags; 1488 return (0); 1489 } 1490 1491 /* 1492 * When possible directly assign passed loaned arc buffer to a dbuf. 1493 * If this is not possible copy the contents of passed arc buf via 1494 * dmu_write(). 1495 */ 1496 int 1497 dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset, arc_buf_t *buf, 1498 dmu_tx_t *tx) 1499 { 1500 dmu_buf_impl_t *db; 1501 objset_t *os = dn->dn_objset; 1502 uint64_t object = dn->dn_object; 1503 uint32_t blksz = (uint32_t)arc_buf_lsize(buf); 1504 uint64_t blkid; 1505 1506 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1507 blkid = dbuf_whichblock(dn, 0, offset); 1508 db = dbuf_hold(dn, blkid, FTAG); 1509 rw_exit(&dn->dn_struct_rwlock); 1510 if (db == NULL) 1511 return (SET_ERROR(EIO)); 1512 1513 /* 1514 * We can only assign if the offset is aligned and the arc buf is the 1515 * same size as the dbuf. 1516 */ 1517 if (offset == db->db.db_offset && blksz == db->db.db_size) { 1518 zfs_racct_write(blksz, 1); 1519 dbuf_assign_arcbuf(db, buf, tx); 1520 dbuf_rele(db, FTAG); 1521 } else { 1522 /* compressed bufs must always be assignable to their dbuf */ 1523 ASSERT3U(arc_get_compression(buf), ==, ZIO_COMPRESS_OFF); 1524 ASSERT(!(buf->b_flags & ARC_BUF_FLAG_COMPRESSED)); 1525 1526 dbuf_rele(db, FTAG); 1527 dmu_write(os, object, offset, blksz, buf->b_data, tx); 1528 dmu_return_arcbuf(buf); 1529 } 1530 1531 return (0); 1532 } 1533 1534 int 1535 dmu_assign_arcbuf_by_dbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 1536 dmu_tx_t *tx) 1537 { 1538 int err; 1539 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle; 1540 1541 DB_DNODE_ENTER(dbuf); 1542 err = dmu_assign_arcbuf_by_dnode(DB_DNODE(dbuf), offset, buf, tx); 1543 DB_DNODE_EXIT(dbuf); 1544 1545 return (err); 1546 } 1547 1548 typedef struct { 1549 dbuf_dirty_record_t *dsa_dr; 1550 dmu_sync_cb_t *dsa_done; 1551 zgd_t *dsa_zgd; 1552 dmu_tx_t *dsa_tx; 1553 } dmu_sync_arg_t; 1554 1555 static void 1556 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 1557 { 1558 (void) buf; 1559 dmu_sync_arg_t *dsa = varg; 1560 dmu_buf_t *db = dsa->dsa_zgd->zgd_db; 1561 blkptr_t *bp = zio->io_bp; 1562 1563 if (zio->io_error == 0) { 1564 if (BP_IS_HOLE(bp)) { 1565 /* 1566 * A block of zeros may compress to a hole, but the 1567 * block size still needs to be known for replay. 1568 */ 1569 BP_SET_LSIZE(bp, db->db_size); 1570 } else if (!BP_IS_EMBEDDED(bp)) { 1571 ASSERT(BP_GET_LEVEL(bp) == 0); 1572 BP_SET_FILL(bp, 1); 1573 } 1574 } 1575 } 1576 1577 static void 1578 dmu_sync_late_arrival_ready(zio_t *zio) 1579 { 1580 dmu_sync_ready(zio, NULL, zio->io_private); 1581 } 1582 1583 static void 1584 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 1585 { 1586 (void) buf; 1587 dmu_sync_arg_t *dsa = varg; 1588 dbuf_dirty_record_t *dr = dsa->dsa_dr; 1589 dmu_buf_impl_t *db = dr->dr_dbuf; 1590 zgd_t *zgd = dsa->dsa_zgd; 1591 1592 /* 1593 * Record the vdev(s) backing this blkptr so they can be flushed after 1594 * the writes for the lwb have completed. 1595 */ 1596 if (zio->io_error == 0) { 1597 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); 1598 } 1599 1600 mutex_enter(&db->db_mtx); 1601 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 1602 if (zio->io_error == 0) { 1603 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE); 1604 if (dr->dt.dl.dr_nopwrite) { 1605 blkptr_t *bp = zio->io_bp; 1606 blkptr_t *bp_orig = &zio->io_bp_orig; 1607 uint8_t chksum = BP_GET_CHECKSUM(bp_orig); 1608 1609 ASSERT(BP_EQUAL(bp, bp_orig)); 1610 VERIFY(BP_EQUAL(bp, db->db_blkptr)); 1611 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF); 1612 VERIFY(zio_checksum_table[chksum].ci_flags & 1613 ZCHECKSUM_FLAG_NOPWRITE); 1614 } 1615 dr->dt.dl.dr_overridden_by = *zio->io_bp; 1616 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 1617 dr->dt.dl.dr_copies = zio->io_prop.zp_copies; 1618 1619 /* 1620 * Old style holes are filled with all zeros, whereas 1621 * new-style holes maintain their lsize, type, level, 1622 * and birth time (see zio_write_compress). While we 1623 * need to reset the BP_SET_LSIZE() call that happened 1624 * in dmu_sync_ready for old style holes, we do *not* 1625 * want to wipe out the information contained in new 1626 * style holes. Thus, only zero out the block pointer if 1627 * it's an old style hole. 1628 */ 1629 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by) && 1630 BP_GET_LOGICAL_BIRTH(&dr->dt.dl.dr_overridden_by) == 0) 1631 BP_ZERO(&dr->dt.dl.dr_overridden_by); 1632 } else { 1633 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; 1634 } 1635 cv_broadcast(&db->db_changed); 1636 mutex_exit(&db->db_mtx); 1637 1638 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1639 1640 kmem_free(dsa, sizeof (*dsa)); 1641 } 1642 1643 static void 1644 dmu_sync_late_arrival_done(zio_t *zio) 1645 { 1646 blkptr_t *bp = zio->io_bp; 1647 dmu_sync_arg_t *dsa = zio->io_private; 1648 zgd_t *zgd = dsa->dsa_zgd; 1649 1650 if (zio->io_error == 0) { 1651 /* 1652 * Record the vdev(s) backing this blkptr so they can be 1653 * flushed after the writes for the lwb have completed. 1654 */ 1655 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); 1656 1657 if (!BP_IS_HOLE(bp)) { 1658 blkptr_t *bp_orig __maybe_unused = &zio->io_bp_orig; 1659 ASSERT(!(zio->io_flags & ZIO_FLAG_NOPWRITE)); 1660 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig)); 1661 ASSERT(BP_GET_LOGICAL_BIRTH(zio->io_bp) == zio->io_txg); 1662 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa)); 1663 zio_free(zio->io_spa, zio->io_txg, zio->io_bp); 1664 } 1665 } 1666 1667 dmu_tx_commit(dsa->dsa_tx); 1668 1669 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1670 1671 abd_free(zio->io_abd); 1672 kmem_free(dsa, sizeof (*dsa)); 1673 } 1674 1675 static int 1676 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, 1677 zio_prop_t *zp, zbookmark_phys_t *zb) 1678 { 1679 dmu_sync_arg_t *dsa; 1680 dmu_tx_t *tx; 1681 int error; 1682 1683 error = dbuf_read((dmu_buf_impl_t *)zgd->zgd_db, NULL, 1684 DB_RF_CANFAIL | DB_RF_NOPREFETCH); 1685 if (error != 0) 1686 return (error); 1687 1688 tx = dmu_tx_create(os); 1689 dmu_tx_hold_space(tx, zgd->zgd_db->db_size); 1690 /* 1691 * This transaction does not produce any dirty data or log blocks, so 1692 * it should not be throttled. All other cases wait for TXG sync, by 1693 * which time the log block we are writing will be obsolete, so we can 1694 * skip waiting and just return error here instead. 1695 */ 1696 if (dmu_tx_assign(tx, TXG_NOWAIT | TXG_NOTHROTTLE) != 0) { 1697 dmu_tx_abort(tx); 1698 /* Make zl_get_data do txg_waited_synced() */ 1699 return (SET_ERROR(EIO)); 1700 } 1701 1702 /* 1703 * In order to prevent the zgd's lwb from being free'd prior to 1704 * dmu_sync_late_arrival_done() being called, we have to ensure 1705 * the lwb's "max txg" takes this tx's txg into account. 1706 */ 1707 zil_lwb_add_txg(zgd->zgd_lwb, dmu_tx_get_txg(tx)); 1708 1709 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1710 dsa->dsa_dr = NULL; 1711 dsa->dsa_done = done; 1712 dsa->dsa_zgd = zgd; 1713 dsa->dsa_tx = tx; 1714 1715 /* 1716 * Since we are currently syncing this txg, it's nontrivial to 1717 * determine what BP to nopwrite against, so we disable nopwrite. 1718 * 1719 * When syncing, the db_blkptr is initially the BP of the previous 1720 * txg. We can not nopwrite against it because it will be changed 1721 * (this is similar to the non-late-arrival case where the dbuf is 1722 * dirty in a future txg). 1723 * 1724 * Then dbuf_write_ready() sets bp_blkptr to the location we will write. 1725 * We can not nopwrite against it because although the BP will not 1726 * (typically) be changed, the data has not yet been persisted to this 1727 * location. 1728 * 1729 * Finally, when dbuf_write_done() is called, it is theoretically 1730 * possible to always nopwrite, because the data that was written in 1731 * this txg is the same data that we are trying to write. However we 1732 * would need to check that this dbuf is not dirty in any future 1733 * txg's (as we do in the normal dmu_sync() path). For simplicity, we 1734 * don't nopwrite in this case. 1735 */ 1736 zp->zp_nopwrite = B_FALSE; 1737 1738 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, 1739 abd_get_from_buf(zgd->zgd_db->db_data, zgd->zgd_db->db_size), 1740 zgd->zgd_db->db_size, zgd->zgd_db->db_size, zp, 1741 dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, 1742 dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb)); 1743 1744 return (0); 1745 } 1746 1747 /* 1748 * Intent log support: sync the block associated with db to disk. 1749 * N.B. and XXX: the caller is responsible for making sure that the 1750 * data isn't changing while dmu_sync() is writing it. 1751 * 1752 * Return values: 1753 * 1754 * EEXIST: this txg has already been synced, so there's nothing to do. 1755 * The caller should not log the write. 1756 * 1757 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 1758 * The caller should not log the write. 1759 * 1760 * EALREADY: this block is already in the process of being synced. 1761 * The caller should track its progress (somehow). 1762 * 1763 * EIO: could not do the I/O. 1764 * The caller should do a txg_wait_synced(). 1765 * 1766 * 0: the I/O has been initiated. 1767 * The caller should log this blkptr in the done callback. 1768 * It is possible that the I/O will fail, in which case 1769 * the error will be reported to the done callback and 1770 * propagated to pio from zio_done(). 1771 */ 1772 int 1773 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) 1774 { 1775 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db; 1776 objset_t *os = db->db_objset; 1777 dsl_dataset_t *ds = os->os_dsl_dataset; 1778 dbuf_dirty_record_t *dr, *dr_next; 1779 dmu_sync_arg_t *dsa; 1780 zbookmark_phys_t zb; 1781 zio_prop_t zp; 1782 dnode_t *dn; 1783 1784 ASSERT(pio != NULL); 1785 ASSERT(txg != 0); 1786 1787 SET_BOOKMARK(&zb, ds->ds_object, 1788 db->db.db_object, db->db_level, db->db_blkid); 1789 1790 DB_DNODE_ENTER(db); 1791 dn = DB_DNODE(db); 1792 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp); 1793 DB_DNODE_EXIT(db); 1794 1795 /* 1796 * If we're frozen (running ziltest), we always need to generate a bp. 1797 */ 1798 if (txg > spa_freeze_txg(os->os_spa)) 1799 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1800 1801 /* 1802 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf() 1803 * and us. If we determine that this txg is not yet syncing, 1804 * but it begins to sync a moment later, that's OK because the 1805 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx. 1806 */ 1807 mutex_enter(&db->db_mtx); 1808 1809 if (txg <= spa_last_synced_txg(os->os_spa)) { 1810 /* 1811 * This txg has already synced. There's nothing to do. 1812 */ 1813 mutex_exit(&db->db_mtx); 1814 return (SET_ERROR(EEXIST)); 1815 } 1816 1817 if (txg <= spa_syncing_txg(os->os_spa)) { 1818 /* 1819 * This txg is currently syncing, so we can't mess with 1820 * the dirty record anymore; just write a new log block. 1821 */ 1822 mutex_exit(&db->db_mtx); 1823 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1824 } 1825 1826 dr = dbuf_find_dirty_eq(db, txg); 1827 1828 if (dr == NULL) { 1829 /* 1830 * There's no dr for this dbuf, so it must have been freed. 1831 * There's no need to log writes to freed blocks, so we're done. 1832 */ 1833 mutex_exit(&db->db_mtx); 1834 return (SET_ERROR(ENOENT)); 1835 } 1836 1837 dr_next = list_next(&db->db_dirty_records, dr); 1838 ASSERT(dr_next == NULL || dr_next->dr_txg < txg); 1839 1840 if (db->db_blkptr != NULL) { 1841 /* 1842 * We need to fill in zgd_bp with the current blkptr so that 1843 * the nopwrite code can check if we're writing the same 1844 * data that's already on disk. We can only nopwrite if we 1845 * are sure that after making the copy, db_blkptr will not 1846 * change until our i/o completes. We ensure this by 1847 * holding the db_mtx, and only allowing nopwrite if the 1848 * block is not already dirty (see below). This is verified 1849 * by dmu_sync_done(), which VERIFYs that the db_blkptr has 1850 * not changed. 1851 */ 1852 *zgd->zgd_bp = *db->db_blkptr; 1853 } 1854 1855 /* 1856 * Assume the on-disk data is X, the current syncing data (in 1857 * txg - 1) is Y, and the current in-memory data is Z (currently 1858 * in dmu_sync). 1859 * 1860 * We usually want to perform a nopwrite if X and Z are the 1861 * same. However, if Y is different (i.e. the BP is going to 1862 * change before this write takes effect), then a nopwrite will 1863 * be incorrect - we would override with X, which could have 1864 * been freed when Y was written. 1865 * 1866 * (Note that this is not a concern when we are nop-writing from 1867 * syncing context, because X and Y must be identical, because 1868 * all previous txgs have been synced.) 1869 * 1870 * Therefore, we disable nopwrite if the current BP could change 1871 * before this TXG. There are two ways it could change: by 1872 * being dirty (dr_next is non-NULL), or by being freed 1873 * (dnode_block_freed()). This behavior is verified by 1874 * zio_done(), which VERIFYs that the override BP is identical 1875 * to the on-disk BP. 1876 */ 1877 DB_DNODE_ENTER(db); 1878 dn = DB_DNODE(db); 1879 if (dr_next != NULL || dnode_block_freed(dn, db->db_blkid)) 1880 zp.zp_nopwrite = B_FALSE; 1881 DB_DNODE_EXIT(db); 1882 1883 ASSERT(dr->dr_txg == txg); 1884 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC || 1885 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1886 /* 1887 * We have already issued a sync write for this buffer, 1888 * or this buffer has already been synced. It could not 1889 * have been dirtied since, or we would have cleared the state. 1890 */ 1891 mutex_exit(&db->db_mtx); 1892 return (SET_ERROR(EALREADY)); 1893 } 1894 1895 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); 1896 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1897 mutex_exit(&db->db_mtx); 1898 1899 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1900 dsa->dsa_dr = dr; 1901 dsa->dsa_done = done; 1902 dsa->dsa_zgd = zgd; 1903 dsa->dsa_tx = NULL; 1904 1905 zio_nowait(arc_write(pio, os->os_spa, txg, zgd->zgd_bp, 1906 dr->dt.dl.dr_data, !DBUF_IS_CACHEABLE(db), dbuf_is_l2cacheable(db), 1907 &zp, dmu_sync_ready, NULL, dmu_sync_done, dsa, 1908 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb)); 1909 1910 return (0); 1911 } 1912 1913 int 1914 dmu_object_set_nlevels(objset_t *os, uint64_t object, int nlevels, dmu_tx_t *tx) 1915 { 1916 dnode_t *dn; 1917 int err; 1918 1919 err = dnode_hold(os, object, FTAG, &dn); 1920 if (err) 1921 return (err); 1922 err = dnode_set_nlevels(dn, nlevels, tx); 1923 dnode_rele(dn, FTAG); 1924 return (err); 1925 } 1926 1927 int 1928 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1929 dmu_tx_t *tx) 1930 { 1931 dnode_t *dn; 1932 int err; 1933 1934 err = dnode_hold(os, object, FTAG, &dn); 1935 if (err) 1936 return (err); 1937 err = dnode_set_blksz(dn, size, ibs, tx); 1938 dnode_rele(dn, FTAG); 1939 return (err); 1940 } 1941 1942 int 1943 dmu_object_set_maxblkid(objset_t *os, uint64_t object, uint64_t maxblkid, 1944 dmu_tx_t *tx) 1945 { 1946 dnode_t *dn; 1947 int err; 1948 1949 err = dnode_hold(os, object, FTAG, &dn); 1950 if (err) 1951 return (err); 1952 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1953 dnode_new_blkid(dn, maxblkid, tx, B_FALSE, B_TRUE); 1954 rw_exit(&dn->dn_struct_rwlock); 1955 dnode_rele(dn, FTAG); 1956 return (0); 1957 } 1958 1959 void 1960 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1961 dmu_tx_t *tx) 1962 { 1963 dnode_t *dn; 1964 1965 /* 1966 * Send streams include each object's checksum function. This 1967 * check ensures that the receiving system can understand the 1968 * checksum function transmitted. 1969 */ 1970 ASSERT3U(checksum, <, ZIO_CHECKSUM_LEGACY_FUNCTIONS); 1971 1972 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1973 ASSERT3U(checksum, <, ZIO_CHECKSUM_FUNCTIONS); 1974 dn->dn_checksum = checksum; 1975 dnode_setdirty(dn, tx); 1976 dnode_rele(dn, FTAG); 1977 } 1978 1979 void 1980 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1981 dmu_tx_t *tx) 1982 { 1983 dnode_t *dn; 1984 1985 /* 1986 * Send streams include each object's compression function. This 1987 * check ensures that the receiving system can understand the 1988 * compression function transmitted. 1989 */ 1990 ASSERT3U(compress, <, ZIO_COMPRESS_LEGACY_FUNCTIONS); 1991 1992 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1993 dn->dn_compress = compress; 1994 dnode_setdirty(dn, tx); 1995 dnode_rele(dn, FTAG); 1996 } 1997 1998 /* 1999 * When the "redundant_metadata" property is set to "most", only indirect 2000 * blocks of this level and higher will have an additional ditto block. 2001 */ 2002 static const int zfs_redundant_metadata_most_ditto_level = 2; 2003 2004 void 2005 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp) 2006 { 2007 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET; 2008 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) || 2009 (wp & WP_SPILL)); 2010 enum zio_checksum checksum = os->os_checksum; 2011 enum zio_compress compress = os->os_compress; 2012 uint8_t complevel = os->os_complevel; 2013 enum zio_checksum dedup_checksum = os->os_dedup_checksum; 2014 boolean_t dedup = B_FALSE; 2015 boolean_t nopwrite = B_FALSE; 2016 boolean_t dedup_verify = os->os_dedup_verify; 2017 boolean_t encrypt = B_FALSE; 2018 int copies = os->os_copies; 2019 2020 /* 2021 * We maintain different write policies for each of the following 2022 * types of data: 2023 * 1. metadata 2024 * 2. preallocated blocks (i.e. level-0 blocks of a dump device) 2025 * 3. all other level 0 blocks 2026 */ 2027 if (ismd) { 2028 /* 2029 * XXX -- we should design a compression algorithm 2030 * that specializes in arrays of bps. 2031 */ 2032 compress = zio_compress_select(os->os_spa, 2033 ZIO_COMPRESS_ON, ZIO_COMPRESS_ON); 2034 2035 /* 2036 * Metadata always gets checksummed. If the data 2037 * checksum is multi-bit correctable, and it's not a 2038 * ZBT-style checksum, then it's suitable for metadata 2039 * as well. Otherwise, the metadata checksum defaults 2040 * to fletcher4. 2041 */ 2042 if (!(zio_checksum_table[checksum].ci_flags & 2043 ZCHECKSUM_FLAG_METADATA) || 2044 (zio_checksum_table[checksum].ci_flags & 2045 ZCHECKSUM_FLAG_EMBEDDED)) 2046 checksum = ZIO_CHECKSUM_FLETCHER_4; 2047 2048 switch (os->os_redundant_metadata) { 2049 case ZFS_REDUNDANT_METADATA_ALL: 2050 copies++; 2051 break; 2052 case ZFS_REDUNDANT_METADATA_MOST: 2053 if (level >= zfs_redundant_metadata_most_ditto_level || 2054 DMU_OT_IS_METADATA(type) || (wp & WP_SPILL)) 2055 copies++; 2056 break; 2057 case ZFS_REDUNDANT_METADATA_SOME: 2058 if (DMU_OT_IS_CRITICAL(type)) 2059 copies++; 2060 break; 2061 case ZFS_REDUNDANT_METADATA_NONE: 2062 break; 2063 } 2064 } else if (wp & WP_NOFILL) { 2065 ASSERT(level == 0); 2066 2067 /* 2068 * If we're writing preallocated blocks, we aren't actually 2069 * writing them so don't set any policy properties. These 2070 * blocks are currently only used by an external subsystem 2071 * outside of zfs (i.e. dump) and not written by the zio 2072 * pipeline. 2073 */ 2074 compress = ZIO_COMPRESS_OFF; 2075 checksum = ZIO_CHECKSUM_OFF; 2076 } else { 2077 compress = zio_compress_select(os->os_spa, dn->dn_compress, 2078 compress); 2079 complevel = zio_complevel_select(os->os_spa, compress, 2080 complevel, complevel); 2081 2082 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ? 2083 zio_checksum_select(dn->dn_checksum, checksum) : 2084 dedup_checksum; 2085 2086 /* 2087 * Determine dedup setting. If we are in dmu_sync(), 2088 * we won't actually dedup now because that's all 2089 * done in syncing context; but we do want to use the 2090 * dedup checksum. If the checksum is not strong 2091 * enough to ensure unique signatures, force 2092 * dedup_verify. 2093 */ 2094 if (dedup_checksum != ZIO_CHECKSUM_OFF) { 2095 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE; 2096 if (!(zio_checksum_table[checksum].ci_flags & 2097 ZCHECKSUM_FLAG_DEDUP)) 2098 dedup_verify = B_TRUE; 2099 } 2100 2101 /* 2102 * Enable nopwrite if we have secure enough checksum 2103 * algorithm (see comment in zio_nop_write) and 2104 * compression is enabled. We don't enable nopwrite if 2105 * dedup is enabled as the two features are mutually 2106 * exclusive. 2107 */ 2108 nopwrite = (!dedup && (zio_checksum_table[checksum].ci_flags & 2109 ZCHECKSUM_FLAG_NOPWRITE) && 2110 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled); 2111 } 2112 2113 /* 2114 * All objects in an encrypted objset are protected from modification 2115 * via a MAC. Encrypted objects store their IV and salt in the last DVA 2116 * in the bp, so we cannot use all copies. Encrypted objects are also 2117 * not subject to nopwrite since writing the same data will still 2118 * result in a new ciphertext. Only encrypted blocks can be dedup'd 2119 * to avoid ambiguity in the dedup code since the DDT does not store 2120 * object types. 2121 */ 2122 if (os->os_encrypted && (wp & WP_NOFILL) == 0) { 2123 encrypt = B_TRUE; 2124 2125 if (DMU_OT_IS_ENCRYPTED(type)) { 2126 copies = MIN(copies, SPA_DVAS_PER_BP - 1); 2127 nopwrite = B_FALSE; 2128 } else { 2129 dedup = B_FALSE; 2130 } 2131 2132 if (level <= 0 && 2133 (type == DMU_OT_DNODE || type == DMU_OT_OBJSET)) { 2134 compress = ZIO_COMPRESS_EMPTY; 2135 } 2136 } 2137 2138 zp->zp_compress = compress; 2139 zp->zp_complevel = complevel; 2140 zp->zp_checksum = checksum; 2141 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type; 2142 zp->zp_level = level; 2143 zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa)); 2144 zp->zp_dedup = dedup; 2145 zp->zp_dedup_verify = dedup && dedup_verify; 2146 zp->zp_nopwrite = nopwrite; 2147 zp->zp_encrypt = encrypt; 2148 zp->zp_byteorder = ZFS_HOST_BYTEORDER; 2149 memset(zp->zp_salt, 0, ZIO_DATA_SALT_LEN); 2150 memset(zp->zp_iv, 0, ZIO_DATA_IV_LEN); 2151 memset(zp->zp_mac, 0, ZIO_DATA_MAC_LEN); 2152 zp->zp_zpl_smallblk = DMU_OT_IS_FILE(zp->zp_type) ? 2153 os->os_zpl_special_smallblock : 0; 2154 2155 ASSERT3U(zp->zp_compress, !=, ZIO_COMPRESS_INHERIT); 2156 } 2157 2158 /* 2159 * Reports the location of data and holes in an object. In order to 2160 * accurately report holes all dirty data must be synced to disk. This 2161 * causes extremely poor performance when seeking for holes in a dirty file. 2162 * As a compromise, only provide hole data when the dnode is clean. When 2163 * a dnode is dirty report the dnode as having no holes by returning EBUSY 2164 * which is always safe to do. 2165 */ 2166 int 2167 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 2168 { 2169 dnode_t *dn; 2170 int restarted = 0, err; 2171 2172 restart: 2173 err = dnode_hold(os, object, FTAG, &dn); 2174 if (err) 2175 return (err); 2176 2177 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2178 2179 if (dnode_is_dirty(dn)) { 2180 /* 2181 * If the zfs_dmu_offset_next_sync module option is enabled 2182 * then hole reporting has been requested. Dirty dnodes 2183 * must be synced to disk to accurately report holes. 2184 * 2185 * Provided a RL_READER rangelock spanning 0-UINT64_MAX is 2186 * held by the caller only a single restart will be required. 2187 * We tolerate callers which do not hold the rangelock by 2188 * returning EBUSY and not reporting holes after one restart. 2189 */ 2190 if (zfs_dmu_offset_next_sync) { 2191 rw_exit(&dn->dn_struct_rwlock); 2192 dnode_rele(dn, FTAG); 2193 2194 if (restarted) 2195 return (SET_ERROR(EBUSY)); 2196 2197 txg_wait_synced(dmu_objset_pool(os), 0); 2198 restarted = 1; 2199 goto restart; 2200 } 2201 2202 err = SET_ERROR(EBUSY); 2203 } else { 2204 err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK | 2205 (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 2206 } 2207 2208 rw_exit(&dn->dn_struct_rwlock); 2209 dnode_rele(dn, FTAG); 2210 2211 return (err); 2212 } 2213 2214 int 2215 dmu_read_l0_bps(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, 2216 blkptr_t *bps, size_t *nbpsp) 2217 { 2218 dmu_buf_t **dbp, *dbuf; 2219 dmu_buf_impl_t *db; 2220 blkptr_t *bp; 2221 int error, numbufs; 2222 2223 error = dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, 2224 &numbufs, &dbp); 2225 if (error != 0) { 2226 if (error == ESRCH) { 2227 error = SET_ERROR(ENXIO); 2228 } 2229 return (error); 2230 } 2231 2232 ASSERT3U(numbufs, <=, *nbpsp); 2233 2234 for (int i = 0; i < numbufs; i++) { 2235 dbuf = dbp[i]; 2236 db = (dmu_buf_impl_t *)dbuf; 2237 2238 mutex_enter(&db->db_mtx); 2239 2240 if (!list_is_empty(&db->db_dirty_records)) { 2241 dbuf_dirty_record_t *dr; 2242 2243 dr = list_head(&db->db_dirty_records); 2244 if (dr->dt.dl.dr_brtwrite) { 2245 /* 2246 * This is very special case where we clone a 2247 * block and in the same transaction group we 2248 * read its BP (most likely to clone the clone). 2249 */ 2250 bp = &dr->dt.dl.dr_overridden_by; 2251 } else { 2252 /* 2253 * The block was modified in the same 2254 * transaction group. 2255 */ 2256 mutex_exit(&db->db_mtx); 2257 error = SET_ERROR(EAGAIN); 2258 goto out; 2259 } 2260 } else { 2261 bp = db->db_blkptr; 2262 } 2263 2264 mutex_exit(&db->db_mtx); 2265 2266 if (bp == NULL) { 2267 /* 2268 * The file size was increased, but the block was never 2269 * written, otherwise we would either have the block 2270 * pointer or the dirty record and would not get here. 2271 * It is effectively a hole, so report it as such. 2272 */ 2273 BP_ZERO(&bps[i]); 2274 continue; 2275 } 2276 /* 2277 * Make sure we clone only data blocks. 2278 */ 2279 if (BP_IS_METADATA(bp) && !BP_IS_HOLE(bp)) { 2280 error = SET_ERROR(EINVAL); 2281 goto out; 2282 } 2283 2284 /* 2285 * If the block was allocated in transaction group that is not 2286 * yet synced, we could clone it, but we couldn't write this 2287 * operation into ZIL, or it may be impossible to replay, since 2288 * the block may appear not yet allocated at that point. 2289 */ 2290 if (BP_GET_BIRTH(bp) > spa_freeze_txg(os->os_spa)) { 2291 error = SET_ERROR(EINVAL); 2292 goto out; 2293 } 2294 if (BP_GET_BIRTH(bp) > spa_last_synced_txg(os->os_spa)) { 2295 error = SET_ERROR(EAGAIN); 2296 goto out; 2297 } 2298 2299 bps[i] = *bp; 2300 } 2301 2302 *nbpsp = numbufs; 2303 out: 2304 dmu_buf_rele_array(dbp, numbufs, FTAG); 2305 2306 return (error); 2307 } 2308 2309 int 2310 dmu_brt_clone(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, 2311 dmu_tx_t *tx, const blkptr_t *bps, size_t nbps) 2312 { 2313 spa_t *spa; 2314 dmu_buf_t **dbp, *dbuf; 2315 dmu_buf_impl_t *db; 2316 struct dirty_leaf *dl; 2317 dbuf_dirty_record_t *dr; 2318 const blkptr_t *bp; 2319 int error = 0, i, numbufs; 2320 2321 spa = os->os_spa; 2322 2323 VERIFY0(dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, 2324 &numbufs, &dbp)); 2325 ASSERT3U(nbps, ==, numbufs); 2326 2327 /* 2328 * Before we start cloning make sure that the dbufs sizes match new BPs 2329 * sizes. If they don't, that's a no-go, as we are not able to shrink 2330 * dbufs. 2331 */ 2332 for (i = 0; i < numbufs; i++) { 2333 dbuf = dbp[i]; 2334 db = (dmu_buf_impl_t *)dbuf; 2335 bp = &bps[i]; 2336 2337 ASSERT0(db->db_level); 2338 ASSERT(db->db_blkid != DMU_BONUS_BLKID); 2339 ASSERT(db->db_blkid != DMU_SPILL_BLKID); 2340 2341 if (!BP_IS_HOLE(bp) && BP_GET_LSIZE(bp) != dbuf->db_size) { 2342 error = SET_ERROR(EXDEV); 2343 goto out; 2344 } 2345 } 2346 2347 for (i = 0; i < numbufs; i++) { 2348 dbuf = dbp[i]; 2349 db = (dmu_buf_impl_t *)dbuf; 2350 bp = &bps[i]; 2351 2352 ASSERT0(db->db_level); 2353 ASSERT(db->db_blkid != DMU_BONUS_BLKID); 2354 ASSERT(db->db_blkid != DMU_SPILL_BLKID); 2355 ASSERT(BP_IS_HOLE(bp) || dbuf->db_size == BP_GET_LSIZE(bp)); 2356 2357 dmu_buf_will_clone(dbuf, tx); 2358 2359 mutex_enter(&db->db_mtx); 2360 2361 dr = list_head(&db->db_dirty_records); 2362 VERIFY(dr != NULL); 2363 ASSERT3U(dr->dr_txg, ==, tx->tx_txg); 2364 dl = &dr->dt.dl; 2365 dl->dr_overridden_by = *bp; 2366 if (!BP_IS_HOLE(bp) || BP_GET_LOGICAL_BIRTH(bp) != 0) { 2367 if (!BP_IS_EMBEDDED(bp)) { 2368 BP_SET_BIRTH(&dl->dr_overridden_by, dr->dr_txg, 2369 BP_GET_BIRTH(bp)); 2370 } else { 2371 BP_SET_LOGICAL_BIRTH(&dl->dr_overridden_by, 2372 dr->dr_txg); 2373 } 2374 } 2375 dl->dr_brtwrite = B_TRUE; 2376 dl->dr_override_state = DR_OVERRIDDEN; 2377 2378 mutex_exit(&db->db_mtx); 2379 2380 /* 2381 * When data in embedded into BP there is no need to create 2382 * BRT entry as there is no data block. Just copy the BP as 2383 * it contains the data. 2384 */ 2385 if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) { 2386 brt_pending_add(spa, bp, tx); 2387 } 2388 } 2389 out: 2390 dmu_buf_rele_array(dbp, numbufs, FTAG); 2391 2392 return (error); 2393 } 2394 2395 void 2396 __dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 2397 { 2398 dnode_phys_t *dnp = dn->dn_phys; 2399 2400 doi->doi_data_block_size = dn->dn_datablksz; 2401 doi->doi_metadata_block_size = dn->dn_indblkshift ? 2402 1ULL << dn->dn_indblkshift : 0; 2403 doi->doi_type = dn->dn_type; 2404 doi->doi_bonus_type = dn->dn_bonustype; 2405 doi->doi_bonus_size = dn->dn_bonuslen; 2406 doi->doi_dnodesize = dn->dn_num_slots << DNODE_SHIFT; 2407 doi->doi_indirection = dn->dn_nlevels; 2408 doi->doi_checksum = dn->dn_checksum; 2409 doi->doi_compress = dn->dn_compress; 2410 doi->doi_nblkptr = dn->dn_nblkptr; 2411 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9; 2412 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 2413 doi->doi_fill_count = 0; 2414 for (int i = 0; i < dnp->dn_nblkptr; i++) 2415 doi->doi_fill_count += BP_GET_FILL(&dnp->dn_blkptr[i]); 2416 } 2417 2418 void 2419 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 2420 { 2421 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2422 mutex_enter(&dn->dn_mtx); 2423 2424 __dmu_object_info_from_dnode(dn, doi); 2425 2426 mutex_exit(&dn->dn_mtx); 2427 rw_exit(&dn->dn_struct_rwlock); 2428 } 2429 2430 /* 2431 * Get information on a DMU object. 2432 * If doi is NULL, just indicates whether the object exists. 2433 */ 2434 int 2435 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 2436 { 2437 dnode_t *dn; 2438 int err = dnode_hold(os, object, FTAG, &dn); 2439 2440 if (err) 2441 return (err); 2442 2443 if (doi != NULL) 2444 dmu_object_info_from_dnode(dn, doi); 2445 2446 dnode_rele(dn, FTAG); 2447 return (0); 2448 } 2449 2450 /* 2451 * As above, but faster; can be used when you have a held dbuf in hand. 2452 */ 2453 void 2454 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi) 2455 { 2456 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2457 2458 DB_DNODE_ENTER(db); 2459 dmu_object_info_from_dnode(DB_DNODE(db), doi); 2460 DB_DNODE_EXIT(db); 2461 } 2462 2463 /* 2464 * Faster still when you only care about the size. 2465 */ 2466 void 2467 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize, 2468 u_longlong_t *nblk512) 2469 { 2470 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2471 dnode_t *dn; 2472 2473 DB_DNODE_ENTER(db); 2474 dn = DB_DNODE(db); 2475 2476 *blksize = dn->dn_datablksz; 2477 /* add in number of slots used for the dnode itself */ 2478 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 2479 SPA_MINBLOCKSHIFT) + dn->dn_num_slots; 2480 DB_DNODE_EXIT(db); 2481 } 2482 2483 void 2484 dmu_object_dnsize_from_db(dmu_buf_t *db_fake, int *dnsize) 2485 { 2486 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2487 dnode_t *dn; 2488 2489 DB_DNODE_ENTER(db); 2490 dn = DB_DNODE(db); 2491 *dnsize = dn->dn_num_slots << DNODE_SHIFT; 2492 DB_DNODE_EXIT(db); 2493 } 2494 2495 void 2496 byteswap_uint64_array(void *vbuf, size_t size) 2497 { 2498 uint64_t *buf = vbuf; 2499 size_t count = size >> 3; 2500 int i; 2501 2502 ASSERT((size & 7) == 0); 2503 2504 for (i = 0; i < count; i++) 2505 buf[i] = BSWAP_64(buf[i]); 2506 } 2507 2508 void 2509 byteswap_uint32_array(void *vbuf, size_t size) 2510 { 2511 uint32_t *buf = vbuf; 2512 size_t count = size >> 2; 2513 int i; 2514 2515 ASSERT((size & 3) == 0); 2516 2517 for (i = 0; i < count; i++) 2518 buf[i] = BSWAP_32(buf[i]); 2519 } 2520 2521 void 2522 byteswap_uint16_array(void *vbuf, size_t size) 2523 { 2524 uint16_t *buf = vbuf; 2525 size_t count = size >> 1; 2526 int i; 2527 2528 ASSERT((size & 1) == 0); 2529 2530 for (i = 0; i < count; i++) 2531 buf[i] = BSWAP_16(buf[i]); 2532 } 2533 2534 void 2535 byteswap_uint8_array(void *vbuf, size_t size) 2536 { 2537 (void) vbuf, (void) size; 2538 } 2539 2540 void 2541 dmu_init(void) 2542 { 2543 abd_init(); 2544 zfs_dbgmsg_init(); 2545 sa_cache_init(); 2546 dmu_objset_init(); 2547 dnode_init(); 2548 zfetch_init(); 2549 dmu_tx_init(); 2550 l2arc_init(); 2551 arc_init(); 2552 dbuf_init(); 2553 } 2554 2555 void 2556 dmu_fini(void) 2557 { 2558 arc_fini(); /* arc depends on l2arc, so arc must go first */ 2559 l2arc_fini(); 2560 dmu_tx_fini(); 2561 zfetch_fini(); 2562 dbuf_fini(); 2563 dnode_fini(); 2564 dmu_objset_fini(); 2565 sa_cache_fini(); 2566 zfs_dbgmsg_fini(); 2567 abd_fini(); 2568 } 2569 2570 EXPORT_SYMBOL(dmu_bonus_hold); 2571 EXPORT_SYMBOL(dmu_bonus_hold_by_dnode); 2572 EXPORT_SYMBOL(dmu_buf_hold_array_by_bonus); 2573 EXPORT_SYMBOL(dmu_buf_rele_array); 2574 EXPORT_SYMBOL(dmu_prefetch); 2575 EXPORT_SYMBOL(dmu_prefetch_by_dnode); 2576 EXPORT_SYMBOL(dmu_prefetch_dnode); 2577 EXPORT_SYMBOL(dmu_free_range); 2578 EXPORT_SYMBOL(dmu_free_long_range); 2579 EXPORT_SYMBOL(dmu_free_long_object); 2580 EXPORT_SYMBOL(dmu_read); 2581 EXPORT_SYMBOL(dmu_read_by_dnode); 2582 EXPORT_SYMBOL(dmu_write); 2583 EXPORT_SYMBOL(dmu_write_by_dnode); 2584 EXPORT_SYMBOL(dmu_prealloc); 2585 EXPORT_SYMBOL(dmu_object_info); 2586 EXPORT_SYMBOL(dmu_object_info_from_dnode); 2587 EXPORT_SYMBOL(dmu_object_info_from_db); 2588 EXPORT_SYMBOL(dmu_object_size_from_db); 2589 EXPORT_SYMBOL(dmu_object_dnsize_from_db); 2590 EXPORT_SYMBOL(dmu_object_set_nlevels); 2591 EXPORT_SYMBOL(dmu_object_set_blocksize); 2592 EXPORT_SYMBOL(dmu_object_set_maxblkid); 2593 EXPORT_SYMBOL(dmu_object_set_checksum); 2594 EXPORT_SYMBOL(dmu_object_set_compress); 2595 EXPORT_SYMBOL(dmu_offset_next); 2596 EXPORT_SYMBOL(dmu_write_policy); 2597 EXPORT_SYMBOL(dmu_sync); 2598 EXPORT_SYMBOL(dmu_request_arcbuf); 2599 EXPORT_SYMBOL(dmu_return_arcbuf); 2600 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dnode); 2601 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dbuf); 2602 EXPORT_SYMBOL(dmu_buf_hold); 2603 EXPORT_SYMBOL(dmu_ot); 2604 2605 ZFS_MODULE_PARAM(zfs, zfs_, nopwrite_enabled, INT, ZMOD_RW, 2606 "Enable NOP writes"); 2607 2608 ZFS_MODULE_PARAM(zfs, zfs_, per_txg_dirty_frees_percent, UINT, ZMOD_RW, 2609 "Percentage of dirtied blocks from frees in one TXG"); 2610 2611 ZFS_MODULE_PARAM(zfs, zfs_, dmu_offset_next_sync, INT, ZMOD_RW, 2612 "Enable forcing txg sync to find holes"); 2613 2614 /* CSTYLED */ 2615 ZFS_MODULE_PARAM(zfs, , dmu_prefetch_max, UINT, ZMOD_RW, 2616 "Limit one prefetch call to this size"); 2617