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(&dn->dn_zfetch, zs, missed, 574 B_TRUE); 575 } 576 rw_exit(&dn->dn_struct_rwlock); 577 dmu_buf_rele_array(dbp, nblks, tag); 578 if (read) 579 zio_nowait(zio); 580 return (SET_ERROR(EIO)); 581 } 582 583 /* 584 * Initiate async demand data read. 585 * We check the db_state after calling dbuf_read() because 586 * (1) dbuf_read() may change the state to CACHED due to a 587 * hit in the ARC, and (2) on a cache miss, a child will 588 * have been added to "zio" but not yet completed, so the 589 * state will not yet be CACHED. 590 */ 591 if (read) { 592 if (i == nblks - 1 && blkid + i < dn->dn_maxblkid && 593 offset + length < db->db.db_offset + 594 db->db.db_size) { 595 if (offset <= db->db.db_offset) 596 dbuf_flags |= DB_RF_PARTIAL_FIRST; 597 else 598 dbuf_flags |= DB_RF_PARTIAL_MORE; 599 } 600 (void) dbuf_read(db, zio, dbuf_flags); 601 if (db->db_state != DB_CACHED) 602 missed = B_TRUE; 603 } 604 dbp[i] = &db->db; 605 } 606 607 if (!read) 608 zfs_racct_write(length, nblks); 609 610 if (zs) 611 dmu_zfetch_run(&dn->dn_zfetch, zs, missed, B_TRUE); 612 rw_exit(&dn->dn_struct_rwlock); 613 614 if (read) { 615 /* wait for async read i/o */ 616 err = zio_wait(zio); 617 if (err) { 618 dmu_buf_rele_array(dbp, nblks, tag); 619 return (err); 620 } 621 622 /* wait for other io to complete */ 623 for (i = 0; i < nblks; i++) { 624 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 625 mutex_enter(&db->db_mtx); 626 while (db->db_state == DB_READ || 627 db->db_state == DB_FILL) 628 cv_wait(&db->db_changed, &db->db_mtx); 629 if (db->db_state == DB_UNCACHED) 630 err = SET_ERROR(EIO); 631 mutex_exit(&db->db_mtx); 632 if (err) { 633 dmu_buf_rele_array(dbp, nblks, tag); 634 return (err); 635 } 636 } 637 } 638 639 *numbufsp = nblks; 640 *dbpp = dbp; 641 return (0); 642 } 643 644 int 645 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 646 uint64_t length, int read, const void *tag, int *numbufsp, 647 dmu_buf_t ***dbpp) 648 { 649 dnode_t *dn; 650 int err; 651 652 err = dnode_hold(os, object, FTAG, &dn); 653 if (err) 654 return (err); 655 656 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 657 numbufsp, dbpp, DMU_READ_PREFETCH); 658 659 dnode_rele(dn, FTAG); 660 661 return (err); 662 } 663 664 int 665 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset, 666 uint64_t length, boolean_t read, const void *tag, int *numbufsp, 667 dmu_buf_t ***dbpp) 668 { 669 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 670 dnode_t *dn; 671 int err; 672 673 DB_DNODE_ENTER(db); 674 dn = DB_DNODE(db); 675 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 676 numbufsp, dbpp, DMU_READ_PREFETCH); 677 DB_DNODE_EXIT(db); 678 679 return (err); 680 } 681 682 void 683 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, const void *tag) 684 { 685 int i; 686 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 687 688 if (numbufs == 0) 689 return; 690 691 for (i = 0; i < numbufs; i++) { 692 if (dbp[i]) 693 dbuf_rele(dbp[i], tag); 694 } 695 696 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 697 } 698 699 /* 700 * Issue prefetch I/Os for the given blocks. If level is greater than 0, the 701 * indirect blocks prefetched will be those that point to the blocks containing 702 * the data starting at offset, and continuing to offset + len. If the range 703 * it too long, prefetch the first dmu_prefetch_max bytes as requested, while 704 * for the rest only a higher level, also fitting within dmu_prefetch_max. It 705 * should primarily help random reads, since for long sequential reads there is 706 * a speculative prefetcher. 707 * 708 * Note that if the indirect blocks above the blocks being prefetched are not 709 * in cache, they will be asynchronously read in. Dnode read by dnode_hold() 710 * is currently synchronous. 711 */ 712 void 713 dmu_prefetch(objset_t *os, uint64_t object, int64_t level, uint64_t offset, 714 uint64_t len, zio_priority_t pri) 715 { 716 dnode_t *dn; 717 718 if (dmu_prefetch_max == 0 || len == 0) { 719 dmu_prefetch_dnode(os, object, pri); 720 return; 721 } 722 723 if (dnode_hold(os, object, FTAG, &dn) != 0) 724 return; 725 726 dmu_prefetch_by_dnode(dn, level, offset, len, pri); 727 728 dnode_rele(dn, FTAG); 729 } 730 731 void 732 dmu_prefetch_by_dnode(dnode_t *dn, int64_t level, uint64_t offset, 733 uint64_t len, zio_priority_t pri) 734 { 735 int64_t level2 = level; 736 uint64_t start, end, start2, end2; 737 738 /* 739 * Depending on len we may do two prefetches: blocks [start, end) at 740 * level, and following blocks [start2, end2) at higher level2. 741 */ 742 rw_enter(&dn->dn_struct_rwlock, RW_READER); 743 if (dn->dn_datablkshift != 0) { 744 /* 745 * The object has multiple blocks. Calculate the full range 746 * of blocks [start, end2) and then split it into two parts, 747 * so that the first [start, end) fits into dmu_prefetch_max. 748 */ 749 start = dbuf_whichblock(dn, level, offset); 750 end2 = dbuf_whichblock(dn, level, offset + len - 1) + 1; 751 uint8_t ibs = dn->dn_indblkshift; 752 uint8_t bs = (level == 0) ? dn->dn_datablkshift : ibs; 753 uint_t limit = P2ROUNDUP(dmu_prefetch_max, 1 << bs) >> bs; 754 start2 = end = MIN(end2, start + limit); 755 756 /* 757 * Find level2 where [start2, end2) fits into dmu_prefetch_max. 758 */ 759 uint8_t ibps = ibs - SPA_BLKPTRSHIFT; 760 limit = P2ROUNDUP(dmu_prefetch_max, 1 << ibs) >> ibs; 761 do { 762 level2++; 763 start2 = P2ROUNDUP(start2, 1 << ibps) >> ibps; 764 end2 = P2ROUNDUP(end2, 1 << ibps) >> ibps; 765 } while (end2 - start2 > limit); 766 } else { 767 /* There is only one block. Prefetch it or nothing. */ 768 start = start2 = end2 = 0; 769 end = start + (level == 0 && offset < dn->dn_datablksz); 770 } 771 772 for (uint64_t i = start; i < end; i++) 773 dbuf_prefetch(dn, level, i, pri, 0); 774 for (uint64_t i = start2; i < end2; i++) 775 dbuf_prefetch(dn, level2, i, pri, 0); 776 rw_exit(&dn->dn_struct_rwlock); 777 } 778 779 /* 780 * Issue prefetch I/Os for the given object's dnode. 781 */ 782 void 783 dmu_prefetch_dnode(objset_t *os, uint64_t object, zio_priority_t pri) 784 { 785 if (object == 0 || object >= DN_MAX_OBJECT) 786 return; 787 788 dnode_t *dn = DMU_META_DNODE(os); 789 rw_enter(&dn->dn_struct_rwlock, RW_READER); 790 uint64_t blkid = dbuf_whichblock(dn, 0, object * sizeof (dnode_phys_t)); 791 dbuf_prefetch(dn, 0, blkid, pri, 0); 792 rw_exit(&dn->dn_struct_rwlock); 793 } 794 795 /* 796 * Get the next "chunk" of file data to free. We traverse the file from 797 * the end so that the file gets shorter over time (if we crashes in the 798 * middle, this will leave us in a better state). We find allocated file 799 * data by simply searching the allocated level 1 indirects. 800 * 801 * On input, *start should be the first offset that does not need to be 802 * freed (e.g. "offset + length"). On return, *start will be the first 803 * offset that should be freed and l1blks is set to the number of level 1 804 * indirect blocks found within the chunk. 805 */ 806 static int 807 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum, uint64_t *l1blks) 808 { 809 uint64_t blks; 810 uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1); 811 /* bytes of data covered by a level-1 indirect block */ 812 uint64_t iblkrange = (uint64_t)dn->dn_datablksz * 813 EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 814 815 ASSERT3U(minimum, <=, *start); 816 817 /* 818 * Check if we can free the entire range assuming that all of the 819 * L1 blocks in this range have data. If we can, we use this 820 * worst case value as an estimate so we can avoid having to look 821 * at the object's actual data. 822 */ 823 uint64_t total_l1blks = 824 (roundup(*start, iblkrange) - (minimum / iblkrange * iblkrange)) / 825 iblkrange; 826 if (total_l1blks <= maxblks) { 827 *l1blks = total_l1blks; 828 *start = minimum; 829 return (0); 830 } 831 ASSERT(ISP2(iblkrange)); 832 833 for (blks = 0; *start > minimum && blks < maxblks; blks++) { 834 int err; 835 836 /* 837 * dnode_next_offset(BACKWARDS) will find an allocated L1 838 * indirect block at or before the input offset. We must 839 * decrement *start so that it is at the end of the region 840 * to search. 841 */ 842 (*start)--; 843 844 err = dnode_next_offset(dn, 845 DNODE_FIND_BACKWARDS, start, 2, 1, 0); 846 847 /* if there are no indirect blocks before start, we are done */ 848 if (err == ESRCH) { 849 *start = minimum; 850 break; 851 } else if (err != 0) { 852 *l1blks = blks; 853 return (err); 854 } 855 856 /* set start to the beginning of this L1 indirect */ 857 *start = P2ALIGN(*start, iblkrange); 858 } 859 if (*start < minimum) 860 *start = minimum; 861 *l1blks = blks; 862 863 return (0); 864 } 865 866 /* 867 * If this objset is of type OST_ZFS return true if vfs's unmounted flag is set, 868 * otherwise return false. 869 * Used below in dmu_free_long_range_impl() to enable abort when unmounting 870 */ 871 static boolean_t 872 dmu_objset_zfs_unmounting(objset_t *os) 873 { 874 #ifdef _KERNEL 875 if (dmu_objset_type(os) == DMU_OST_ZFS) 876 return (zfs_get_vfs_flag_unmounted(os)); 877 #else 878 (void) os; 879 #endif 880 return (B_FALSE); 881 } 882 883 static int 884 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 885 uint64_t length) 886 { 887 uint64_t object_size; 888 int err; 889 uint64_t dirty_frees_threshold; 890 dsl_pool_t *dp = dmu_objset_pool(os); 891 892 if (dn == NULL) 893 return (SET_ERROR(EINVAL)); 894 895 object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 896 if (offset >= object_size) 897 return (0); 898 899 if (zfs_per_txg_dirty_frees_percent <= 100) 900 dirty_frees_threshold = 901 zfs_per_txg_dirty_frees_percent * zfs_dirty_data_max / 100; 902 else 903 dirty_frees_threshold = zfs_dirty_data_max / 20; 904 905 if (length == DMU_OBJECT_END || offset + length > object_size) 906 length = object_size - offset; 907 908 while (length != 0) { 909 uint64_t chunk_end, chunk_begin, chunk_len; 910 uint64_t l1blks; 911 dmu_tx_t *tx; 912 913 if (dmu_objset_zfs_unmounting(dn->dn_objset)) 914 return (SET_ERROR(EINTR)); 915 916 chunk_end = chunk_begin = offset + length; 917 918 /* move chunk_begin backwards to the beginning of this chunk */ 919 err = get_next_chunk(dn, &chunk_begin, offset, &l1blks); 920 if (err) 921 return (err); 922 ASSERT3U(chunk_begin, >=, offset); 923 ASSERT3U(chunk_begin, <=, chunk_end); 924 925 chunk_len = chunk_end - chunk_begin; 926 927 tx = dmu_tx_create(os); 928 dmu_tx_hold_free(tx, dn->dn_object, chunk_begin, chunk_len); 929 930 /* 931 * Mark this transaction as typically resulting in a net 932 * reduction in space used. 933 */ 934 dmu_tx_mark_netfree(tx); 935 err = dmu_tx_assign(tx, TXG_WAIT); 936 if (err) { 937 dmu_tx_abort(tx); 938 return (err); 939 } 940 941 uint64_t txg = dmu_tx_get_txg(tx); 942 943 mutex_enter(&dp->dp_lock); 944 uint64_t long_free_dirty = 945 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK]; 946 mutex_exit(&dp->dp_lock); 947 948 /* 949 * To avoid filling up a TXG with just frees, wait for 950 * the next TXG to open before freeing more chunks if 951 * we have reached the threshold of frees. 952 */ 953 if (dirty_frees_threshold != 0 && 954 long_free_dirty >= dirty_frees_threshold) { 955 DMU_TX_STAT_BUMP(dmu_tx_dirty_frees_delay); 956 dmu_tx_commit(tx); 957 txg_wait_open(dp, 0, B_TRUE); 958 continue; 959 } 960 961 /* 962 * In order to prevent unnecessary write throttling, for each 963 * TXG, we track the cumulative size of L1 blocks being dirtied 964 * in dnode_free_range() below. We compare this number to a 965 * tunable threshold, past which we prevent new L1 dirty freeing 966 * blocks from being added into the open TXG. See 967 * dmu_free_long_range_impl() for details. The threshold 968 * prevents write throttle activation due to dirty freeing L1 969 * blocks taking up a large percentage of zfs_dirty_data_max. 970 */ 971 mutex_enter(&dp->dp_lock); 972 dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] += 973 l1blks << dn->dn_indblkshift; 974 mutex_exit(&dp->dp_lock); 975 DTRACE_PROBE3(free__long__range, 976 uint64_t, long_free_dirty, uint64_t, chunk_len, 977 uint64_t, txg); 978 dnode_free_range(dn, chunk_begin, chunk_len, tx); 979 980 dmu_tx_commit(tx); 981 982 length -= chunk_len; 983 } 984 return (0); 985 } 986 987 int 988 dmu_free_long_range(objset_t *os, uint64_t object, 989 uint64_t offset, uint64_t length) 990 { 991 dnode_t *dn; 992 int err; 993 994 err = dnode_hold(os, object, FTAG, &dn); 995 if (err != 0) 996 return (err); 997 err = dmu_free_long_range_impl(os, dn, offset, length); 998 999 /* 1000 * It is important to zero out the maxblkid when freeing the entire 1001 * file, so that (a) subsequent calls to dmu_free_long_range_impl() 1002 * will take the fast path, and (b) dnode_reallocate() can verify 1003 * that the entire file has been freed. 1004 */ 1005 if (err == 0 && offset == 0 && length == DMU_OBJECT_END) 1006 dn->dn_maxblkid = 0; 1007 1008 dnode_rele(dn, FTAG); 1009 return (err); 1010 } 1011 1012 int 1013 dmu_free_long_object(objset_t *os, uint64_t object) 1014 { 1015 dmu_tx_t *tx; 1016 int err; 1017 1018 err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END); 1019 if (err != 0) 1020 return (err); 1021 1022 tx = dmu_tx_create(os); 1023 dmu_tx_hold_bonus(tx, object); 1024 dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END); 1025 dmu_tx_mark_netfree(tx); 1026 err = dmu_tx_assign(tx, TXG_WAIT); 1027 if (err == 0) { 1028 err = dmu_object_free(os, object, tx); 1029 dmu_tx_commit(tx); 1030 } else { 1031 dmu_tx_abort(tx); 1032 } 1033 1034 return (err); 1035 } 1036 1037 int 1038 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 1039 uint64_t size, dmu_tx_t *tx) 1040 { 1041 dnode_t *dn; 1042 int err = dnode_hold(os, object, FTAG, &dn); 1043 if (err) 1044 return (err); 1045 ASSERT(offset < UINT64_MAX); 1046 ASSERT(size == DMU_OBJECT_END || size <= UINT64_MAX - offset); 1047 dnode_free_range(dn, offset, size, tx); 1048 dnode_rele(dn, FTAG); 1049 return (0); 1050 } 1051 1052 static int 1053 dmu_read_impl(dnode_t *dn, uint64_t offset, uint64_t size, 1054 void *buf, uint32_t flags) 1055 { 1056 dmu_buf_t **dbp; 1057 int numbufs, err = 0; 1058 1059 /* 1060 * Deal with odd block sizes, where there can't be data past the first 1061 * block. If we ever do the tail block optimization, we will need to 1062 * handle that here as well. 1063 */ 1064 if (dn->dn_maxblkid == 0) { 1065 uint64_t newsz = offset > dn->dn_datablksz ? 0 : 1066 MIN(size, dn->dn_datablksz - offset); 1067 memset((char *)buf + newsz, 0, size - newsz); 1068 size = newsz; 1069 } 1070 1071 while (size > 0) { 1072 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 1073 int i; 1074 1075 /* 1076 * NB: we could do this block-at-a-time, but it's nice 1077 * to be reading in parallel. 1078 */ 1079 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 1080 TRUE, FTAG, &numbufs, &dbp, flags); 1081 if (err) 1082 break; 1083 1084 for (i = 0; i < numbufs; i++) { 1085 uint64_t tocpy; 1086 int64_t bufoff; 1087 dmu_buf_t *db = dbp[i]; 1088 1089 ASSERT(size > 0); 1090 1091 bufoff = offset - db->db_offset; 1092 tocpy = MIN(db->db_size - bufoff, size); 1093 1094 (void) memcpy(buf, (char *)db->db_data + bufoff, tocpy); 1095 1096 offset += tocpy; 1097 size -= tocpy; 1098 buf = (char *)buf + tocpy; 1099 } 1100 dmu_buf_rele_array(dbp, numbufs, FTAG); 1101 } 1102 return (err); 1103 } 1104 1105 int 1106 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1107 void *buf, uint32_t flags) 1108 { 1109 dnode_t *dn; 1110 int err; 1111 1112 err = dnode_hold(os, object, FTAG, &dn); 1113 if (err != 0) 1114 return (err); 1115 1116 err = dmu_read_impl(dn, offset, size, buf, flags); 1117 dnode_rele(dn, FTAG); 1118 return (err); 1119 } 1120 1121 int 1122 dmu_read_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, void *buf, 1123 uint32_t flags) 1124 { 1125 return (dmu_read_impl(dn, offset, size, buf, flags)); 1126 } 1127 1128 static void 1129 dmu_write_impl(dmu_buf_t **dbp, int numbufs, uint64_t offset, uint64_t size, 1130 const void *buf, dmu_tx_t *tx) 1131 { 1132 int i; 1133 1134 for (i = 0; i < numbufs; i++) { 1135 uint64_t tocpy; 1136 int64_t bufoff; 1137 dmu_buf_t *db = dbp[i]; 1138 1139 ASSERT(size > 0); 1140 1141 bufoff = offset - db->db_offset; 1142 tocpy = MIN(db->db_size - bufoff, size); 1143 1144 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1145 1146 if (tocpy == db->db_size) 1147 dmu_buf_will_fill(db, tx, B_FALSE); 1148 else 1149 dmu_buf_will_dirty(db, tx); 1150 1151 (void) memcpy((char *)db->db_data + bufoff, buf, tocpy); 1152 1153 if (tocpy == db->db_size) 1154 dmu_buf_fill_done(db, tx, B_FALSE); 1155 1156 offset += tocpy; 1157 size -= tocpy; 1158 buf = (char *)buf + tocpy; 1159 } 1160 } 1161 1162 void 1163 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1164 const void *buf, dmu_tx_t *tx) 1165 { 1166 dmu_buf_t **dbp; 1167 int numbufs; 1168 1169 if (size == 0) 1170 return; 1171 1172 VERIFY0(dmu_buf_hold_array(os, object, offset, size, 1173 FALSE, FTAG, &numbufs, &dbp)); 1174 dmu_write_impl(dbp, numbufs, offset, size, buf, tx); 1175 dmu_buf_rele_array(dbp, numbufs, FTAG); 1176 } 1177 1178 /* 1179 * Note: Lustre is an external consumer of this interface. 1180 */ 1181 void 1182 dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, 1183 const void *buf, dmu_tx_t *tx) 1184 { 1185 dmu_buf_t **dbp; 1186 int numbufs; 1187 1188 if (size == 0) 1189 return; 1190 1191 VERIFY0(dmu_buf_hold_array_by_dnode(dn, offset, size, 1192 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH)); 1193 dmu_write_impl(dbp, numbufs, offset, size, buf, tx); 1194 dmu_buf_rele_array(dbp, numbufs, FTAG); 1195 } 1196 1197 void 1198 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1199 dmu_tx_t *tx) 1200 { 1201 dmu_buf_t **dbp; 1202 int numbufs, i; 1203 1204 if (size == 0) 1205 return; 1206 1207 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 1208 FALSE, FTAG, &numbufs, &dbp)); 1209 1210 for (i = 0; i < numbufs; i++) { 1211 dmu_buf_t *db = dbp[i]; 1212 1213 dmu_buf_will_not_fill(db, tx); 1214 } 1215 dmu_buf_rele_array(dbp, numbufs, FTAG); 1216 } 1217 1218 void 1219 dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset, 1220 void *data, uint8_t etype, uint8_t comp, int uncompressed_size, 1221 int compressed_size, int byteorder, dmu_tx_t *tx) 1222 { 1223 dmu_buf_t *db; 1224 1225 ASSERT3U(etype, <, NUM_BP_EMBEDDED_TYPES); 1226 ASSERT3U(comp, <, ZIO_COMPRESS_FUNCTIONS); 1227 VERIFY0(dmu_buf_hold_noread(os, object, offset, 1228 FTAG, &db)); 1229 1230 dmu_buf_write_embedded(db, 1231 data, (bp_embedded_type_t)etype, (enum zio_compress)comp, 1232 uncompressed_size, compressed_size, byteorder, tx); 1233 1234 dmu_buf_rele(db, FTAG); 1235 } 1236 1237 void 1238 dmu_redact(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1239 dmu_tx_t *tx) 1240 { 1241 int numbufs, i; 1242 dmu_buf_t **dbp; 1243 1244 VERIFY0(dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, 1245 &numbufs, &dbp)); 1246 for (i = 0; i < numbufs; i++) 1247 dmu_buf_redact(dbp[i], tx); 1248 dmu_buf_rele_array(dbp, numbufs, FTAG); 1249 } 1250 1251 #ifdef _KERNEL 1252 int 1253 dmu_read_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size) 1254 { 1255 dmu_buf_t **dbp; 1256 int numbufs, i, err; 1257 1258 /* 1259 * NB: we could do this block-at-a-time, but it's nice 1260 * to be reading in parallel. 1261 */ 1262 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, 1263 TRUE, FTAG, &numbufs, &dbp, 0); 1264 if (err) 1265 return (err); 1266 1267 for (i = 0; i < numbufs; i++) { 1268 uint64_t tocpy; 1269 int64_t bufoff; 1270 dmu_buf_t *db = dbp[i]; 1271 1272 ASSERT(size > 0); 1273 1274 bufoff = zfs_uio_offset(uio) - db->db_offset; 1275 tocpy = MIN(db->db_size - bufoff, size); 1276 1277 err = zfs_uio_fault_move((char *)db->db_data + bufoff, tocpy, 1278 UIO_READ, uio); 1279 1280 if (err) 1281 break; 1282 1283 size -= tocpy; 1284 } 1285 dmu_buf_rele_array(dbp, numbufs, FTAG); 1286 1287 return (err); 1288 } 1289 1290 /* 1291 * Read 'size' bytes into the uio buffer. 1292 * From object zdb->db_object. 1293 * Starting at zfs_uio_offset(uio). 1294 * 1295 * If the caller already has a dbuf in the target object 1296 * (e.g. its bonus buffer), this routine is faster than dmu_read_uio(), 1297 * because we don't have to find the dnode_t for the object. 1298 */ 1299 int 1300 dmu_read_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size) 1301 { 1302 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1303 dnode_t *dn; 1304 int err; 1305 1306 if (size == 0) 1307 return (0); 1308 1309 DB_DNODE_ENTER(db); 1310 dn = DB_DNODE(db); 1311 err = dmu_read_uio_dnode(dn, uio, size); 1312 DB_DNODE_EXIT(db); 1313 1314 return (err); 1315 } 1316 1317 /* 1318 * Read 'size' bytes into the uio buffer. 1319 * From the specified object 1320 * Starting at offset zfs_uio_offset(uio). 1321 */ 1322 int 1323 dmu_read_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size) 1324 { 1325 dnode_t *dn; 1326 int err; 1327 1328 if (size == 0) 1329 return (0); 1330 1331 err = dnode_hold(os, object, FTAG, &dn); 1332 if (err) 1333 return (err); 1334 1335 err = dmu_read_uio_dnode(dn, uio, size); 1336 1337 dnode_rele(dn, FTAG); 1338 1339 return (err); 1340 } 1341 1342 int 1343 dmu_write_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx) 1344 { 1345 dmu_buf_t **dbp; 1346 int numbufs; 1347 int err = 0; 1348 int i; 1349 1350 err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, 1351 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH); 1352 if (err) 1353 return (err); 1354 1355 for (i = 0; i < numbufs; i++) { 1356 uint64_t tocpy; 1357 int64_t bufoff; 1358 dmu_buf_t *db = dbp[i]; 1359 1360 ASSERT(size > 0); 1361 1362 offset_t off = zfs_uio_offset(uio); 1363 bufoff = off - db->db_offset; 1364 tocpy = MIN(db->db_size - bufoff, size); 1365 1366 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1367 1368 if (tocpy == db->db_size) 1369 dmu_buf_will_fill(db, tx, B_TRUE); 1370 else 1371 dmu_buf_will_dirty(db, tx); 1372 1373 err = zfs_uio_fault_move((char *)db->db_data + bufoff, 1374 tocpy, UIO_WRITE, uio); 1375 1376 if (tocpy == db->db_size && dmu_buf_fill_done(db, tx, err)) { 1377 /* The fill was reverted. Undo any uio progress. */ 1378 zfs_uio_advance(uio, off - zfs_uio_offset(uio)); 1379 } 1380 1381 if (err) 1382 break; 1383 1384 size -= tocpy; 1385 } 1386 1387 dmu_buf_rele_array(dbp, numbufs, FTAG); 1388 return (err); 1389 } 1390 1391 /* 1392 * Write 'size' bytes from the uio buffer. 1393 * To object zdb->db_object. 1394 * Starting at offset zfs_uio_offset(uio). 1395 * 1396 * If the caller already has a dbuf in the target object 1397 * (e.g. its bonus buffer), this routine is faster than dmu_write_uio(), 1398 * because we don't have to find the dnode_t for the object. 1399 */ 1400 int 1401 dmu_write_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size, 1402 dmu_tx_t *tx) 1403 { 1404 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1405 dnode_t *dn; 1406 int err; 1407 1408 if (size == 0) 1409 return (0); 1410 1411 DB_DNODE_ENTER(db); 1412 dn = DB_DNODE(db); 1413 err = dmu_write_uio_dnode(dn, uio, size, tx); 1414 DB_DNODE_EXIT(db); 1415 1416 return (err); 1417 } 1418 1419 /* 1420 * Write 'size' bytes from the uio buffer. 1421 * To the specified object. 1422 * Starting at offset zfs_uio_offset(uio). 1423 */ 1424 int 1425 dmu_write_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size, 1426 dmu_tx_t *tx) 1427 { 1428 dnode_t *dn; 1429 int err; 1430 1431 if (size == 0) 1432 return (0); 1433 1434 err = dnode_hold(os, object, FTAG, &dn); 1435 if (err) 1436 return (err); 1437 1438 err = dmu_write_uio_dnode(dn, uio, size, tx); 1439 1440 dnode_rele(dn, FTAG); 1441 1442 return (err); 1443 } 1444 #endif /* _KERNEL */ 1445 1446 /* 1447 * Allocate a loaned anonymous arc buffer. 1448 */ 1449 arc_buf_t * 1450 dmu_request_arcbuf(dmu_buf_t *handle, int size) 1451 { 1452 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle; 1453 1454 return (arc_loan_buf(db->db_objset->os_spa, B_FALSE, size)); 1455 } 1456 1457 /* 1458 * Free a loaned arc buffer. 1459 */ 1460 void 1461 dmu_return_arcbuf(arc_buf_t *buf) 1462 { 1463 arc_return_buf(buf, FTAG); 1464 arc_buf_destroy(buf, FTAG); 1465 } 1466 1467 /* 1468 * A "lightweight" write is faster than a regular write (e.g. 1469 * dmu_write_by_dnode() or dmu_assign_arcbuf_by_dnode()), because it avoids the 1470 * CPU cost of creating a dmu_buf_impl_t and arc_buf_[hdr_]_t. However, the 1471 * data can not be read or overwritten until the transaction's txg has been 1472 * synced. This makes it appropriate for workloads that are known to be 1473 * (temporarily) write-only, like "zfs receive". 1474 * 1475 * A single block is written, starting at the specified offset in bytes. If 1476 * the call is successful, it returns 0 and the provided abd has been 1477 * consumed (the caller should not free it). 1478 */ 1479 int 1480 dmu_lightweight_write_by_dnode(dnode_t *dn, uint64_t offset, abd_t *abd, 1481 const zio_prop_t *zp, zio_flag_t flags, dmu_tx_t *tx) 1482 { 1483 dbuf_dirty_record_t *dr = 1484 dbuf_dirty_lightweight(dn, dbuf_whichblock(dn, 0, offset), tx); 1485 if (dr == NULL) 1486 return (SET_ERROR(EIO)); 1487 dr->dt.dll.dr_abd = abd; 1488 dr->dt.dll.dr_props = *zp; 1489 dr->dt.dll.dr_flags = flags; 1490 return (0); 1491 } 1492 1493 /* 1494 * When possible directly assign passed loaned arc buffer to a dbuf. 1495 * If this is not possible copy the contents of passed arc buf via 1496 * dmu_write(). 1497 */ 1498 int 1499 dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset, arc_buf_t *buf, 1500 dmu_tx_t *tx) 1501 { 1502 dmu_buf_impl_t *db; 1503 objset_t *os = dn->dn_objset; 1504 uint64_t object = dn->dn_object; 1505 uint32_t blksz = (uint32_t)arc_buf_lsize(buf); 1506 uint64_t blkid; 1507 1508 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1509 blkid = dbuf_whichblock(dn, 0, offset); 1510 db = dbuf_hold(dn, blkid, FTAG); 1511 rw_exit(&dn->dn_struct_rwlock); 1512 if (db == NULL) 1513 return (SET_ERROR(EIO)); 1514 1515 /* 1516 * We can only assign if the offset is aligned and the arc buf is the 1517 * same size as the dbuf. 1518 */ 1519 if (offset == db->db.db_offset && blksz == db->db.db_size) { 1520 zfs_racct_write(blksz, 1); 1521 dbuf_assign_arcbuf(db, buf, tx); 1522 dbuf_rele(db, FTAG); 1523 } else { 1524 /* compressed bufs must always be assignable to their dbuf */ 1525 ASSERT3U(arc_get_compression(buf), ==, ZIO_COMPRESS_OFF); 1526 ASSERT(!(buf->b_flags & ARC_BUF_FLAG_COMPRESSED)); 1527 1528 dbuf_rele(db, FTAG); 1529 dmu_write(os, object, offset, blksz, buf->b_data, tx); 1530 dmu_return_arcbuf(buf); 1531 } 1532 1533 return (0); 1534 } 1535 1536 int 1537 dmu_assign_arcbuf_by_dbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 1538 dmu_tx_t *tx) 1539 { 1540 int err; 1541 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle; 1542 1543 DB_DNODE_ENTER(dbuf); 1544 err = dmu_assign_arcbuf_by_dnode(DB_DNODE(dbuf), offset, buf, tx); 1545 DB_DNODE_EXIT(dbuf); 1546 1547 return (err); 1548 } 1549 1550 typedef struct { 1551 dbuf_dirty_record_t *dsa_dr; 1552 dmu_sync_cb_t *dsa_done; 1553 zgd_t *dsa_zgd; 1554 dmu_tx_t *dsa_tx; 1555 } dmu_sync_arg_t; 1556 1557 static void 1558 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 1559 { 1560 (void) buf; 1561 dmu_sync_arg_t *dsa = varg; 1562 dmu_buf_t *db = dsa->dsa_zgd->zgd_db; 1563 blkptr_t *bp = zio->io_bp; 1564 1565 if (zio->io_error == 0) { 1566 if (BP_IS_HOLE(bp)) { 1567 /* 1568 * A block of zeros may compress to a hole, but the 1569 * block size still needs to be known for replay. 1570 */ 1571 BP_SET_LSIZE(bp, db->db_size); 1572 } else if (!BP_IS_EMBEDDED(bp)) { 1573 ASSERT(BP_GET_LEVEL(bp) == 0); 1574 BP_SET_FILL(bp, 1); 1575 } 1576 } 1577 } 1578 1579 static void 1580 dmu_sync_late_arrival_ready(zio_t *zio) 1581 { 1582 dmu_sync_ready(zio, NULL, zio->io_private); 1583 } 1584 1585 static void 1586 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 1587 { 1588 (void) buf; 1589 dmu_sync_arg_t *dsa = varg; 1590 dbuf_dirty_record_t *dr = dsa->dsa_dr; 1591 dmu_buf_impl_t *db = dr->dr_dbuf; 1592 zgd_t *zgd = dsa->dsa_zgd; 1593 1594 /* 1595 * Record the vdev(s) backing this blkptr so they can be flushed after 1596 * the writes for the lwb have completed. 1597 */ 1598 if (zio->io_error == 0) { 1599 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); 1600 } 1601 1602 mutex_enter(&db->db_mtx); 1603 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 1604 if (zio->io_error == 0) { 1605 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE); 1606 if (dr->dt.dl.dr_nopwrite) { 1607 blkptr_t *bp = zio->io_bp; 1608 blkptr_t *bp_orig = &zio->io_bp_orig; 1609 uint8_t chksum = BP_GET_CHECKSUM(bp_orig); 1610 1611 ASSERT(BP_EQUAL(bp, bp_orig)); 1612 VERIFY(BP_EQUAL(bp, db->db_blkptr)); 1613 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF); 1614 VERIFY(zio_checksum_table[chksum].ci_flags & 1615 ZCHECKSUM_FLAG_NOPWRITE); 1616 } 1617 dr->dt.dl.dr_overridden_by = *zio->io_bp; 1618 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 1619 dr->dt.dl.dr_copies = zio->io_prop.zp_copies; 1620 1621 /* 1622 * Old style holes are filled with all zeros, whereas 1623 * new-style holes maintain their lsize, type, level, 1624 * and birth time (see zio_write_compress). While we 1625 * need to reset the BP_SET_LSIZE() call that happened 1626 * in dmu_sync_ready for old style holes, we do *not* 1627 * want to wipe out the information contained in new 1628 * style holes. Thus, only zero out the block pointer if 1629 * it's an old style hole. 1630 */ 1631 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by) && 1632 BP_GET_LOGICAL_BIRTH(&dr->dt.dl.dr_overridden_by) == 0) 1633 BP_ZERO(&dr->dt.dl.dr_overridden_by); 1634 } else { 1635 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; 1636 } 1637 cv_broadcast(&db->db_changed); 1638 mutex_exit(&db->db_mtx); 1639 1640 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1641 1642 kmem_free(dsa, sizeof (*dsa)); 1643 } 1644 1645 static void 1646 dmu_sync_late_arrival_done(zio_t *zio) 1647 { 1648 blkptr_t *bp = zio->io_bp; 1649 dmu_sync_arg_t *dsa = zio->io_private; 1650 zgd_t *zgd = dsa->dsa_zgd; 1651 1652 if (zio->io_error == 0) { 1653 /* 1654 * Record the vdev(s) backing this blkptr so they can be 1655 * flushed after the writes for the lwb have completed. 1656 */ 1657 zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); 1658 1659 if (!BP_IS_HOLE(bp)) { 1660 blkptr_t *bp_orig __maybe_unused = &zio->io_bp_orig; 1661 ASSERT(!(zio->io_flags & ZIO_FLAG_NOPWRITE)); 1662 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig)); 1663 ASSERT(BP_GET_LOGICAL_BIRTH(zio->io_bp) == zio->io_txg); 1664 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa)); 1665 zio_free(zio->io_spa, zio->io_txg, zio->io_bp); 1666 } 1667 } 1668 1669 dmu_tx_commit(dsa->dsa_tx); 1670 1671 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1672 1673 abd_free(zio->io_abd); 1674 kmem_free(dsa, sizeof (*dsa)); 1675 } 1676 1677 static int 1678 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, 1679 zio_prop_t *zp, zbookmark_phys_t *zb) 1680 { 1681 dmu_sync_arg_t *dsa; 1682 dmu_tx_t *tx; 1683 int error; 1684 1685 error = dbuf_read((dmu_buf_impl_t *)zgd->zgd_db, NULL, 1686 DB_RF_CANFAIL | DB_RF_NOPREFETCH); 1687 if (error != 0) 1688 return (error); 1689 1690 tx = dmu_tx_create(os); 1691 dmu_tx_hold_space(tx, zgd->zgd_db->db_size); 1692 /* 1693 * This transaction does not produce any dirty data or log blocks, so 1694 * it should not be throttled. All other cases wait for TXG sync, by 1695 * which time the log block we are writing will be obsolete, so we can 1696 * skip waiting and just return error here instead. 1697 */ 1698 if (dmu_tx_assign(tx, TXG_NOWAIT | TXG_NOTHROTTLE) != 0) { 1699 dmu_tx_abort(tx); 1700 /* Make zl_get_data do txg_waited_synced() */ 1701 return (SET_ERROR(EIO)); 1702 } 1703 1704 /* 1705 * In order to prevent the zgd's lwb from being free'd prior to 1706 * dmu_sync_late_arrival_done() being called, we have to ensure 1707 * the lwb's "max txg" takes this tx's txg into account. 1708 */ 1709 zil_lwb_add_txg(zgd->zgd_lwb, dmu_tx_get_txg(tx)); 1710 1711 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1712 dsa->dsa_dr = NULL; 1713 dsa->dsa_done = done; 1714 dsa->dsa_zgd = zgd; 1715 dsa->dsa_tx = tx; 1716 1717 /* 1718 * Since we are currently syncing this txg, it's nontrivial to 1719 * determine what BP to nopwrite against, so we disable nopwrite. 1720 * 1721 * When syncing, the db_blkptr is initially the BP of the previous 1722 * txg. We can not nopwrite against it because it will be changed 1723 * (this is similar to the non-late-arrival case where the dbuf is 1724 * dirty in a future txg). 1725 * 1726 * Then dbuf_write_ready() sets bp_blkptr to the location we will write. 1727 * We can not nopwrite against it because although the BP will not 1728 * (typically) be changed, the data has not yet been persisted to this 1729 * location. 1730 * 1731 * Finally, when dbuf_write_done() is called, it is theoretically 1732 * possible to always nopwrite, because the data that was written in 1733 * this txg is the same data that we are trying to write. However we 1734 * would need to check that this dbuf is not dirty in any future 1735 * txg's (as we do in the normal dmu_sync() path). For simplicity, we 1736 * don't nopwrite in this case. 1737 */ 1738 zp->zp_nopwrite = B_FALSE; 1739 1740 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, 1741 abd_get_from_buf(zgd->zgd_db->db_data, zgd->zgd_db->db_size), 1742 zgd->zgd_db->db_size, zgd->zgd_db->db_size, zp, 1743 dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, 1744 dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb)); 1745 1746 return (0); 1747 } 1748 1749 /* 1750 * Intent log support: sync the block associated with db to disk. 1751 * N.B. and XXX: the caller is responsible for making sure that the 1752 * data isn't changing while dmu_sync() is writing it. 1753 * 1754 * Return values: 1755 * 1756 * EEXIST: this txg has already been synced, so there's nothing to do. 1757 * The caller should not log the write. 1758 * 1759 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 1760 * The caller should not log the write. 1761 * 1762 * EALREADY: this block is already in the process of being synced. 1763 * The caller should track its progress (somehow). 1764 * 1765 * EIO: could not do the I/O. 1766 * The caller should do a txg_wait_synced(). 1767 * 1768 * 0: the I/O has been initiated. 1769 * The caller should log this blkptr in the done callback. 1770 * It is possible that the I/O will fail, in which case 1771 * the error will be reported to the done callback and 1772 * propagated to pio from zio_done(). 1773 */ 1774 int 1775 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) 1776 { 1777 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db; 1778 objset_t *os = db->db_objset; 1779 dsl_dataset_t *ds = os->os_dsl_dataset; 1780 dbuf_dirty_record_t *dr, *dr_next; 1781 dmu_sync_arg_t *dsa; 1782 zbookmark_phys_t zb; 1783 zio_prop_t zp; 1784 dnode_t *dn; 1785 1786 ASSERT(pio != NULL); 1787 ASSERT(txg != 0); 1788 1789 SET_BOOKMARK(&zb, ds->ds_object, 1790 db->db.db_object, db->db_level, db->db_blkid); 1791 1792 DB_DNODE_ENTER(db); 1793 dn = DB_DNODE(db); 1794 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp); 1795 DB_DNODE_EXIT(db); 1796 1797 /* 1798 * If we're frozen (running ziltest), we always need to generate a bp. 1799 */ 1800 if (txg > spa_freeze_txg(os->os_spa)) 1801 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1802 1803 /* 1804 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf() 1805 * and us. If we determine that this txg is not yet syncing, 1806 * but it begins to sync a moment later, that's OK because the 1807 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx. 1808 */ 1809 mutex_enter(&db->db_mtx); 1810 1811 if (txg <= spa_last_synced_txg(os->os_spa)) { 1812 /* 1813 * This txg has already synced. There's nothing to do. 1814 */ 1815 mutex_exit(&db->db_mtx); 1816 return (SET_ERROR(EEXIST)); 1817 } 1818 1819 if (txg <= spa_syncing_txg(os->os_spa)) { 1820 /* 1821 * This txg is currently syncing, so we can't mess with 1822 * the dirty record anymore; just write a new log block. 1823 */ 1824 mutex_exit(&db->db_mtx); 1825 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1826 } 1827 1828 dr = dbuf_find_dirty_eq(db, txg); 1829 1830 if (dr == NULL) { 1831 /* 1832 * There's no dr for this dbuf, so it must have been freed. 1833 * There's no need to log writes to freed blocks, so we're done. 1834 */ 1835 mutex_exit(&db->db_mtx); 1836 return (SET_ERROR(ENOENT)); 1837 } 1838 1839 dr_next = list_next(&db->db_dirty_records, dr); 1840 ASSERT(dr_next == NULL || dr_next->dr_txg < txg); 1841 1842 if (db->db_blkptr != NULL) { 1843 /* 1844 * We need to fill in zgd_bp with the current blkptr so that 1845 * the nopwrite code can check if we're writing the same 1846 * data that's already on disk. We can only nopwrite if we 1847 * are sure that after making the copy, db_blkptr will not 1848 * change until our i/o completes. We ensure this by 1849 * holding the db_mtx, and only allowing nopwrite if the 1850 * block is not already dirty (see below). This is verified 1851 * by dmu_sync_done(), which VERIFYs that the db_blkptr has 1852 * not changed. 1853 */ 1854 *zgd->zgd_bp = *db->db_blkptr; 1855 } 1856 1857 /* 1858 * Assume the on-disk data is X, the current syncing data (in 1859 * txg - 1) is Y, and the current in-memory data is Z (currently 1860 * in dmu_sync). 1861 * 1862 * We usually want to perform a nopwrite if X and Z are the 1863 * same. However, if Y is different (i.e. the BP is going to 1864 * change before this write takes effect), then a nopwrite will 1865 * be incorrect - we would override with X, which could have 1866 * been freed when Y was written. 1867 * 1868 * (Note that this is not a concern when we are nop-writing from 1869 * syncing context, because X and Y must be identical, because 1870 * all previous txgs have been synced.) 1871 * 1872 * Therefore, we disable nopwrite if the current BP could change 1873 * before this TXG. There are two ways it could change: by 1874 * being dirty (dr_next is non-NULL), or by being freed 1875 * (dnode_block_freed()). This behavior is verified by 1876 * zio_done(), which VERIFYs that the override BP is identical 1877 * to the on-disk BP. 1878 */ 1879 DB_DNODE_ENTER(db); 1880 dn = DB_DNODE(db); 1881 if (dr_next != NULL || dnode_block_freed(dn, db->db_blkid)) 1882 zp.zp_nopwrite = B_FALSE; 1883 DB_DNODE_EXIT(db); 1884 1885 ASSERT(dr->dr_txg == txg); 1886 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC || 1887 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1888 /* 1889 * We have already issued a sync write for this buffer, 1890 * or this buffer has already been synced. It could not 1891 * have been dirtied since, or we would have cleared the state. 1892 */ 1893 mutex_exit(&db->db_mtx); 1894 return (SET_ERROR(EALREADY)); 1895 } 1896 1897 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); 1898 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1899 mutex_exit(&db->db_mtx); 1900 1901 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1902 dsa->dsa_dr = dr; 1903 dsa->dsa_done = done; 1904 dsa->dsa_zgd = zgd; 1905 dsa->dsa_tx = NULL; 1906 1907 zio_nowait(arc_write(pio, os->os_spa, txg, zgd->zgd_bp, 1908 dr->dt.dl.dr_data, !DBUF_IS_CACHEABLE(db), dbuf_is_l2cacheable(db), 1909 &zp, dmu_sync_ready, NULL, dmu_sync_done, dsa, 1910 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb)); 1911 1912 return (0); 1913 } 1914 1915 int 1916 dmu_object_set_nlevels(objset_t *os, uint64_t object, int nlevels, dmu_tx_t *tx) 1917 { 1918 dnode_t *dn; 1919 int err; 1920 1921 err = dnode_hold(os, object, FTAG, &dn); 1922 if (err) 1923 return (err); 1924 err = dnode_set_nlevels(dn, nlevels, tx); 1925 dnode_rele(dn, FTAG); 1926 return (err); 1927 } 1928 1929 int 1930 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1931 dmu_tx_t *tx) 1932 { 1933 dnode_t *dn; 1934 int err; 1935 1936 err = dnode_hold(os, object, FTAG, &dn); 1937 if (err) 1938 return (err); 1939 err = dnode_set_blksz(dn, size, ibs, tx); 1940 dnode_rele(dn, FTAG); 1941 return (err); 1942 } 1943 1944 int 1945 dmu_object_set_maxblkid(objset_t *os, uint64_t object, uint64_t maxblkid, 1946 dmu_tx_t *tx) 1947 { 1948 dnode_t *dn; 1949 int err; 1950 1951 err = dnode_hold(os, object, FTAG, &dn); 1952 if (err) 1953 return (err); 1954 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1955 dnode_new_blkid(dn, maxblkid, tx, B_FALSE, B_TRUE); 1956 rw_exit(&dn->dn_struct_rwlock); 1957 dnode_rele(dn, FTAG); 1958 return (0); 1959 } 1960 1961 void 1962 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1963 dmu_tx_t *tx) 1964 { 1965 dnode_t *dn; 1966 1967 /* 1968 * Send streams include each object's checksum function. This 1969 * check ensures that the receiving system can understand the 1970 * checksum function transmitted. 1971 */ 1972 ASSERT3U(checksum, <, ZIO_CHECKSUM_LEGACY_FUNCTIONS); 1973 1974 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1975 ASSERT3U(checksum, <, ZIO_CHECKSUM_FUNCTIONS); 1976 dn->dn_checksum = checksum; 1977 dnode_setdirty(dn, tx); 1978 dnode_rele(dn, FTAG); 1979 } 1980 1981 void 1982 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1983 dmu_tx_t *tx) 1984 { 1985 dnode_t *dn; 1986 1987 /* 1988 * Send streams include each object's compression function. This 1989 * check ensures that the receiving system can understand the 1990 * compression function transmitted. 1991 */ 1992 ASSERT3U(compress, <, ZIO_COMPRESS_LEGACY_FUNCTIONS); 1993 1994 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1995 dn->dn_compress = compress; 1996 dnode_setdirty(dn, tx); 1997 dnode_rele(dn, FTAG); 1998 } 1999 2000 /* 2001 * When the "redundant_metadata" property is set to "most", only indirect 2002 * blocks of this level and higher will have an additional ditto block. 2003 */ 2004 static const int zfs_redundant_metadata_most_ditto_level = 2; 2005 2006 void 2007 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp) 2008 { 2009 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET; 2010 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) || 2011 (wp & WP_SPILL)); 2012 enum zio_checksum checksum = os->os_checksum; 2013 enum zio_compress compress = os->os_compress; 2014 uint8_t complevel = os->os_complevel; 2015 enum zio_checksum dedup_checksum = os->os_dedup_checksum; 2016 boolean_t dedup = B_FALSE; 2017 boolean_t nopwrite = B_FALSE; 2018 boolean_t dedup_verify = os->os_dedup_verify; 2019 boolean_t encrypt = B_FALSE; 2020 int copies = os->os_copies; 2021 2022 /* 2023 * We maintain different write policies for each of the following 2024 * types of data: 2025 * 1. metadata 2026 * 2. preallocated blocks (i.e. level-0 blocks of a dump device) 2027 * 3. all other level 0 blocks 2028 */ 2029 if (ismd) { 2030 /* 2031 * XXX -- we should design a compression algorithm 2032 * that specializes in arrays of bps. 2033 */ 2034 compress = zio_compress_select(os->os_spa, 2035 ZIO_COMPRESS_ON, ZIO_COMPRESS_ON); 2036 2037 /* 2038 * Metadata always gets checksummed. If the data 2039 * checksum is multi-bit correctable, and it's not a 2040 * ZBT-style checksum, then it's suitable for metadata 2041 * as well. Otherwise, the metadata checksum defaults 2042 * to fletcher4. 2043 */ 2044 if (!(zio_checksum_table[checksum].ci_flags & 2045 ZCHECKSUM_FLAG_METADATA) || 2046 (zio_checksum_table[checksum].ci_flags & 2047 ZCHECKSUM_FLAG_EMBEDDED)) 2048 checksum = ZIO_CHECKSUM_FLETCHER_4; 2049 2050 switch (os->os_redundant_metadata) { 2051 case ZFS_REDUNDANT_METADATA_ALL: 2052 copies++; 2053 break; 2054 case ZFS_REDUNDANT_METADATA_MOST: 2055 if (level >= zfs_redundant_metadata_most_ditto_level || 2056 DMU_OT_IS_METADATA(type) || (wp & WP_SPILL)) 2057 copies++; 2058 break; 2059 case ZFS_REDUNDANT_METADATA_SOME: 2060 if (DMU_OT_IS_CRITICAL(type)) 2061 copies++; 2062 break; 2063 case ZFS_REDUNDANT_METADATA_NONE: 2064 break; 2065 } 2066 } else if (wp & WP_NOFILL) { 2067 ASSERT(level == 0); 2068 2069 /* 2070 * If we're writing preallocated blocks, we aren't actually 2071 * writing them so don't set any policy properties. These 2072 * blocks are currently only used by an external subsystem 2073 * outside of zfs (i.e. dump) and not written by the zio 2074 * pipeline. 2075 */ 2076 compress = ZIO_COMPRESS_OFF; 2077 checksum = ZIO_CHECKSUM_OFF; 2078 } else { 2079 compress = zio_compress_select(os->os_spa, dn->dn_compress, 2080 compress); 2081 complevel = zio_complevel_select(os->os_spa, compress, 2082 complevel, complevel); 2083 2084 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ? 2085 zio_checksum_select(dn->dn_checksum, checksum) : 2086 dedup_checksum; 2087 2088 /* 2089 * Determine dedup setting. If we are in dmu_sync(), 2090 * we won't actually dedup now because that's all 2091 * done in syncing context; but we do want to use the 2092 * dedup checksum. If the checksum is not strong 2093 * enough to ensure unique signatures, force 2094 * dedup_verify. 2095 */ 2096 if (dedup_checksum != ZIO_CHECKSUM_OFF) { 2097 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE; 2098 if (!(zio_checksum_table[checksum].ci_flags & 2099 ZCHECKSUM_FLAG_DEDUP)) 2100 dedup_verify = B_TRUE; 2101 } 2102 2103 /* 2104 * Enable nopwrite if we have secure enough checksum 2105 * algorithm (see comment in zio_nop_write) and 2106 * compression is enabled. We don't enable nopwrite if 2107 * dedup is enabled as the two features are mutually 2108 * exclusive. 2109 */ 2110 nopwrite = (!dedup && (zio_checksum_table[checksum].ci_flags & 2111 ZCHECKSUM_FLAG_NOPWRITE) && 2112 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled); 2113 } 2114 2115 /* 2116 * All objects in an encrypted objset are protected from modification 2117 * via a MAC. Encrypted objects store their IV and salt in the last DVA 2118 * in the bp, so we cannot use all copies. Encrypted objects are also 2119 * not subject to nopwrite since writing the same data will still 2120 * result in a new ciphertext. Only encrypted blocks can be dedup'd 2121 * to avoid ambiguity in the dedup code since the DDT does not store 2122 * object types. 2123 */ 2124 if (os->os_encrypted && (wp & WP_NOFILL) == 0) { 2125 encrypt = B_TRUE; 2126 2127 if (DMU_OT_IS_ENCRYPTED(type)) { 2128 copies = MIN(copies, SPA_DVAS_PER_BP - 1); 2129 nopwrite = B_FALSE; 2130 } else { 2131 dedup = B_FALSE; 2132 } 2133 2134 if (level <= 0 && 2135 (type == DMU_OT_DNODE || type == DMU_OT_OBJSET)) { 2136 compress = ZIO_COMPRESS_EMPTY; 2137 } 2138 } 2139 2140 zp->zp_compress = compress; 2141 zp->zp_complevel = complevel; 2142 zp->zp_checksum = checksum; 2143 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type; 2144 zp->zp_level = level; 2145 zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa)); 2146 zp->zp_dedup = dedup; 2147 zp->zp_dedup_verify = dedup && dedup_verify; 2148 zp->zp_nopwrite = nopwrite; 2149 zp->zp_encrypt = encrypt; 2150 zp->zp_byteorder = ZFS_HOST_BYTEORDER; 2151 memset(zp->zp_salt, 0, ZIO_DATA_SALT_LEN); 2152 memset(zp->zp_iv, 0, ZIO_DATA_IV_LEN); 2153 memset(zp->zp_mac, 0, ZIO_DATA_MAC_LEN); 2154 zp->zp_zpl_smallblk = DMU_OT_IS_FILE(zp->zp_type) ? 2155 os->os_zpl_special_smallblock : 0; 2156 2157 ASSERT3U(zp->zp_compress, !=, ZIO_COMPRESS_INHERIT); 2158 } 2159 2160 /* 2161 * Reports the location of data and holes in an object. In order to 2162 * accurately report holes all dirty data must be synced to disk. This 2163 * causes extremely poor performance when seeking for holes in a dirty file. 2164 * As a compromise, only provide hole data when the dnode is clean. When 2165 * a dnode is dirty report the dnode as having no holes by returning EBUSY 2166 * which is always safe to do. 2167 */ 2168 int 2169 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 2170 { 2171 dnode_t *dn; 2172 int restarted = 0, err; 2173 2174 restart: 2175 err = dnode_hold(os, object, FTAG, &dn); 2176 if (err) 2177 return (err); 2178 2179 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2180 2181 if (dnode_is_dirty(dn)) { 2182 /* 2183 * If the zfs_dmu_offset_next_sync module option is enabled 2184 * then hole reporting has been requested. Dirty dnodes 2185 * must be synced to disk to accurately report holes. 2186 * 2187 * Provided a RL_READER rangelock spanning 0-UINT64_MAX is 2188 * held by the caller only a single restart will be required. 2189 * We tolerate callers which do not hold the rangelock by 2190 * returning EBUSY and not reporting holes after one restart. 2191 */ 2192 if (zfs_dmu_offset_next_sync) { 2193 rw_exit(&dn->dn_struct_rwlock); 2194 dnode_rele(dn, FTAG); 2195 2196 if (restarted) 2197 return (SET_ERROR(EBUSY)); 2198 2199 txg_wait_synced(dmu_objset_pool(os), 0); 2200 restarted = 1; 2201 goto restart; 2202 } 2203 2204 err = SET_ERROR(EBUSY); 2205 } else { 2206 err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK | 2207 (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 2208 } 2209 2210 rw_exit(&dn->dn_struct_rwlock); 2211 dnode_rele(dn, FTAG); 2212 2213 return (err); 2214 } 2215 2216 int 2217 dmu_read_l0_bps(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, 2218 blkptr_t *bps, size_t *nbpsp) 2219 { 2220 dmu_buf_t **dbp, *dbuf; 2221 dmu_buf_impl_t *db; 2222 blkptr_t *bp; 2223 int error, numbufs; 2224 2225 error = dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, 2226 &numbufs, &dbp); 2227 if (error != 0) { 2228 if (error == ESRCH) { 2229 error = SET_ERROR(ENXIO); 2230 } 2231 return (error); 2232 } 2233 2234 ASSERT3U(numbufs, <=, *nbpsp); 2235 2236 for (int i = 0; i < numbufs; i++) { 2237 dbuf = dbp[i]; 2238 db = (dmu_buf_impl_t *)dbuf; 2239 2240 mutex_enter(&db->db_mtx); 2241 2242 if (!list_is_empty(&db->db_dirty_records)) { 2243 dbuf_dirty_record_t *dr; 2244 2245 dr = list_head(&db->db_dirty_records); 2246 if (dr->dt.dl.dr_brtwrite) { 2247 /* 2248 * This is very special case where we clone a 2249 * block and in the same transaction group we 2250 * read its BP (most likely to clone the clone). 2251 */ 2252 bp = &dr->dt.dl.dr_overridden_by; 2253 } else { 2254 /* 2255 * The block was modified in the same 2256 * transaction group. 2257 */ 2258 mutex_exit(&db->db_mtx); 2259 error = SET_ERROR(EAGAIN); 2260 goto out; 2261 } 2262 } else { 2263 bp = db->db_blkptr; 2264 } 2265 2266 mutex_exit(&db->db_mtx); 2267 2268 if (bp == NULL) { 2269 /* 2270 * The file size was increased, but the block was never 2271 * written, otherwise we would either have the block 2272 * pointer or the dirty record and would not get here. 2273 * It is effectively a hole, so report it as such. 2274 */ 2275 BP_ZERO(&bps[i]); 2276 continue; 2277 } 2278 /* 2279 * Make sure we clone only data blocks. 2280 */ 2281 if (BP_IS_METADATA(bp) && !BP_IS_HOLE(bp)) { 2282 error = SET_ERROR(EINVAL); 2283 goto out; 2284 } 2285 2286 /* 2287 * If the block was allocated in transaction group that is not 2288 * yet synced, we could clone it, but we couldn't write this 2289 * operation into ZIL, or it may be impossible to replay, since 2290 * the block may appear not yet allocated at that point. 2291 */ 2292 if (BP_GET_BIRTH(bp) > spa_freeze_txg(os->os_spa)) { 2293 error = SET_ERROR(EINVAL); 2294 goto out; 2295 } 2296 if (BP_GET_BIRTH(bp) > spa_last_synced_txg(os->os_spa)) { 2297 error = SET_ERROR(EAGAIN); 2298 goto out; 2299 } 2300 2301 bps[i] = *bp; 2302 } 2303 2304 *nbpsp = numbufs; 2305 out: 2306 dmu_buf_rele_array(dbp, numbufs, FTAG); 2307 2308 return (error); 2309 } 2310 2311 int 2312 dmu_brt_clone(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, 2313 dmu_tx_t *tx, const blkptr_t *bps, size_t nbps) 2314 { 2315 spa_t *spa; 2316 dmu_buf_t **dbp, *dbuf; 2317 dmu_buf_impl_t *db; 2318 struct dirty_leaf *dl; 2319 dbuf_dirty_record_t *dr; 2320 const blkptr_t *bp; 2321 int error = 0, i, numbufs; 2322 2323 spa = os->os_spa; 2324 2325 VERIFY0(dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, 2326 &numbufs, &dbp)); 2327 ASSERT3U(nbps, ==, numbufs); 2328 2329 /* 2330 * Before we start cloning make sure that the dbufs sizes match new BPs 2331 * sizes. If they don't, that's a no-go, as we are not able to shrink 2332 * dbufs. 2333 */ 2334 for (i = 0; i < numbufs; i++) { 2335 dbuf = dbp[i]; 2336 db = (dmu_buf_impl_t *)dbuf; 2337 bp = &bps[i]; 2338 2339 ASSERT0(db->db_level); 2340 ASSERT(db->db_blkid != DMU_BONUS_BLKID); 2341 ASSERT(db->db_blkid != DMU_SPILL_BLKID); 2342 2343 if (!BP_IS_HOLE(bp) && BP_GET_LSIZE(bp) != dbuf->db_size) { 2344 error = SET_ERROR(EXDEV); 2345 goto out; 2346 } 2347 } 2348 2349 for (i = 0; i < numbufs; i++) { 2350 dbuf = dbp[i]; 2351 db = (dmu_buf_impl_t *)dbuf; 2352 bp = &bps[i]; 2353 2354 ASSERT0(db->db_level); 2355 ASSERT(db->db_blkid != DMU_BONUS_BLKID); 2356 ASSERT(db->db_blkid != DMU_SPILL_BLKID); 2357 ASSERT(BP_IS_HOLE(bp) || dbuf->db_size == BP_GET_LSIZE(bp)); 2358 2359 dmu_buf_will_clone(dbuf, tx); 2360 2361 mutex_enter(&db->db_mtx); 2362 2363 dr = list_head(&db->db_dirty_records); 2364 VERIFY(dr != NULL); 2365 ASSERT3U(dr->dr_txg, ==, tx->tx_txg); 2366 dl = &dr->dt.dl; 2367 dl->dr_overridden_by = *bp; 2368 if (!BP_IS_HOLE(bp) || BP_GET_LOGICAL_BIRTH(bp) != 0) { 2369 if (!BP_IS_EMBEDDED(bp)) { 2370 BP_SET_BIRTH(&dl->dr_overridden_by, dr->dr_txg, 2371 BP_GET_BIRTH(bp)); 2372 } else { 2373 BP_SET_LOGICAL_BIRTH(&dl->dr_overridden_by, 2374 dr->dr_txg); 2375 } 2376 } 2377 dl->dr_brtwrite = B_TRUE; 2378 dl->dr_override_state = DR_OVERRIDDEN; 2379 2380 mutex_exit(&db->db_mtx); 2381 2382 /* 2383 * When data in embedded into BP there is no need to create 2384 * BRT entry as there is no data block. Just copy the BP as 2385 * it contains the data. 2386 */ 2387 if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) { 2388 brt_pending_add(spa, bp, tx); 2389 } 2390 } 2391 out: 2392 dmu_buf_rele_array(dbp, numbufs, FTAG); 2393 2394 return (error); 2395 } 2396 2397 void 2398 __dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 2399 { 2400 dnode_phys_t *dnp = dn->dn_phys; 2401 2402 doi->doi_data_block_size = dn->dn_datablksz; 2403 doi->doi_metadata_block_size = dn->dn_indblkshift ? 2404 1ULL << dn->dn_indblkshift : 0; 2405 doi->doi_type = dn->dn_type; 2406 doi->doi_bonus_type = dn->dn_bonustype; 2407 doi->doi_bonus_size = dn->dn_bonuslen; 2408 doi->doi_dnodesize = dn->dn_num_slots << DNODE_SHIFT; 2409 doi->doi_indirection = dn->dn_nlevels; 2410 doi->doi_checksum = dn->dn_checksum; 2411 doi->doi_compress = dn->dn_compress; 2412 doi->doi_nblkptr = dn->dn_nblkptr; 2413 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9; 2414 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 2415 doi->doi_fill_count = 0; 2416 for (int i = 0; i < dnp->dn_nblkptr; i++) 2417 doi->doi_fill_count += BP_GET_FILL(&dnp->dn_blkptr[i]); 2418 } 2419 2420 void 2421 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 2422 { 2423 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2424 mutex_enter(&dn->dn_mtx); 2425 2426 __dmu_object_info_from_dnode(dn, doi); 2427 2428 mutex_exit(&dn->dn_mtx); 2429 rw_exit(&dn->dn_struct_rwlock); 2430 } 2431 2432 /* 2433 * Get information on a DMU object. 2434 * If doi is NULL, just indicates whether the object exists. 2435 */ 2436 int 2437 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 2438 { 2439 dnode_t *dn; 2440 int err = dnode_hold(os, object, FTAG, &dn); 2441 2442 if (err) 2443 return (err); 2444 2445 if (doi != NULL) 2446 dmu_object_info_from_dnode(dn, doi); 2447 2448 dnode_rele(dn, FTAG); 2449 return (0); 2450 } 2451 2452 /* 2453 * As above, but faster; can be used when you have a held dbuf in hand. 2454 */ 2455 void 2456 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi) 2457 { 2458 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2459 2460 DB_DNODE_ENTER(db); 2461 dmu_object_info_from_dnode(DB_DNODE(db), doi); 2462 DB_DNODE_EXIT(db); 2463 } 2464 2465 /* 2466 * Faster still when you only care about the size. 2467 */ 2468 void 2469 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize, 2470 u_longlong_t *nblk512) 2471 { 2472 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2473 dnode_t *dn; 2474 2475 DB_DNODE_ENTER(db); 2476 dn = DB_DNODE(db); 2477 2478 *blksize = dn->dn_datablksz; 2479 /* add in number of slots used for the dnode itself */ 2480 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 2481 SPA_MINBLOCKSHIFT) + dn->dn_num_slots; 2482 DB_DNODE_EXIT(db); 2483 } 2484 2485 void 2486 dmu_object_dnsize_from_db(dmu_buf_t *db_fake, int *dnsize) 2487 { 2488 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 2489 dnode_t *dn; 2490 2491 DB_DNODE_ENTER(db); 2492 dn = DB_DNODE(db); 2493 *dnsize = dn->dn_num_slots << DNODE_SHIFT; 2494 DB_DNODE_EXIT(db); 2495 } 2496 2497 void 2498 byteswap_uint64_array(void *vbuf, size_t size) 2499 { 2500 uint64_t *buf = vbuf; 2501 size_t count = size >> 3; 2502 int i; 2503 2504 ASSERT((size & 7) == 0); 2505 2506 for (i = 0; i < count; i++) 2507 buf[i] = BSWAP_64(buf[i]); 2508 } 2509 2510 void 2511 byteswap_uint32_array(void *vbuf, size_t size) 2512 { 2513 uint32_t *buf = vbuf; 2514 size_t count = size >> 2; 2515 int i; 2516 2517 ASSERT((size & 3) == 0); 2518 2519 for (i = 0; i < count; i++) 2520 buf[i] = BSWAP_32(buf[i]); 2521 } 2522 2523 void 2524 byteswap_uint16_array(void *vbuf, size_t size) 2525 { 2526 uint16_t *buf = vbuf; 2527 size_t count = size >> 1; 2528 int i; 2529 2530 ASSERT((size & 1) == 0); 2531 2532 for (i = 0; i < count; i++) 2533 buf[i] = BSWAP_16(buf[i]); 2534 } 2535 2536 void 2537 byteswap_uint8_array(void *vbuf, size_t size) 2538 { 2539 (void) vbuf, (void) size; 2540 } 2541 2542 void 2543 dmu_init(void) 2544 { 2545 abd_init(); 2546 zfs_dbgmsg_init(); 2547 sa_cache_init(); 2548 dmu_objset_init(); 2549 dnode_init(); 2550 zfetch_init(); 2551 dmu_tx_init(); 2552 l2arc_init(); 2553 arc_init(); 2554 dbuf_init(); 2555 } 2556 2557 void 2558 dmu_fini(void) 2559 { 2560 arc_fini(); /* arc depends on l2arc, so arc must go first */ 2561 l2arc_fini(); 2562 dmu_tx_fini(); 2563 zfetch_fini(); 2564 dbuf_fini(); 2565 dnode_fini(); 2566 dmu_objset_fini(); 2567 sa_cache_fini(); 2568 zfs_dbgmsg_fini(); 2569 abd_fini(); 2570 } 2571 2572 EXPORT_SYMBOL(dmu_bonus_hold); 2573 EXPORT_SYMBOL(dmu_bonus_hold_by_dnode); 2574 EXPORT_SYMBOL(dmu_buf_hold_array_by_bonus); 2575 EXPORT_SYMBOL(dmu_buf_rele_array); 2576 EXPORT_SYMBOL(dmu_prefetch); 2577 EXPORT_SYMBOL(dmu_prefetch_by_dnode); 2578 EXPORT_SYMBOL(dmu_prefetch_dnode); 2579 EXPORT_SYMBOL(dmu_free_range); 2580 EXPORT_SYMBOL(dmu_free_long_range); 2581 EXPORT_SYMBOL(dmu_free_long_object); 2582 EXPORT_SYMBOL(dmu_read); 2583 EXPORT_SYMBOL(dmu_read_by_dnode); 2584 EXPORT_SYMBOL(dmu_write); 2585 EXPORT_SYMBOL(dmu_write_by_dnode); 2586 EXPORT_SYMBOL(dmu_prealloc); 2587 EXPORT_SYMBOL(dmu_object_info); 2588 EXPORT_SYMBOL(dmu_object_info_from_dnode); 2589 EXPORT_SYMBOL(dmu_object_info_from_db); 2590 EXPORT_SYMBOL(dmu_object_size_from_db); 2591 EXPORT_SYMBOL(dmu_object_dnsize_from_db); 2592 EXPORT_SYMBOL(dmu_object_set_nlevels); 2593 EXPORT_SYMBOL(dmu_object_set_blocksize); 2594 EXPORT_SYMBOL(dmu_object_set_maxblkid); 2595 EXPORT_SYMBOL(dmu_object_set_checksum); 2596 EXPORT_SYMBOL(dmu_object_set_compress); 2597 EXPORT_SYMBOL(dmu_offset_next); 2598 EXPORT_SYMBOL(dmu_write_policy); 2599 EXPORT_SYMBOL(dmu_sync); 2600 EXPORT_SYMBOL(dmu_request_arcbuf); 2601 EXPORT_SYMBOL(dmu_return_arcbuf); 2602 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dnode); 2603 EXPORT_SYMBOL(dmu_assign_arcbuf_by_dbuf); 2604 EXPORT_SYMBOL(dmu_buf_hold); 2605 EXPORT_SYMBOL(dmu_ot); 2606 2607 ZFS_MODULE_PARAM(zfs, zfs_, nopwrite_enabled, INT, ZMOD_RW, 2608 "Enable NOP writes"); 2609 2610 ZFS_MODULE_PARAM(zfs, zfs_, per_txg_dirty_frees_percent, UINT, ZMOD_RW, 2611 "Percentage of dirtied blocks from frees in one TXG"); 2612 2613 ZFS_MODULE_PARAM(zfs, zfs_, dmu_offset_next_sync, INT, ZMOD_RW, 2614 "Enable forcing txg sync to find holes"); 2615 2616 /* CSTYLED */ 2617 ZFS_MODULE_PARAM(zfs, , dmu_prefetch_max, UINT, ZMOD_RW, 2618 "Limit one prefetch call to this size"); 2619