1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2014 by Delphix. All rights reserved. 24 */ 25 /* Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */ 26 /* Copyright (c) 2013, Joyent, Inc. All rights reserved. */ 27 /* Copyright (c) 2014, Nexenta Systems, Inc. All rights reserved. */ 28 29 #include <sys/dmu.h> 30 #include <sys/dmu_impl.h> 31 #include <sys/dmu_tx.h> 32 #include <sys/dbuf.h> 33 #include <sys/dnode.h> 34 #include <sys/zfs_context.h> 35 #include <sys/dmu_objset.h> 36 #include <sys/dmu_traverse.h> 37 #include <sys/dsl_dataset.h> 38 #include <sys/dsl_dir.h> 39 #include <sys/dsl_pool.h> 40 #include <sys/dsl_synctask.h> 41 #include <sys/dsl_prop.h> 42 #include <sys/dmu_zfetch.h> 43 #include <sys/zfs_ioctl.h> 44 #include <sys/zap.h> 45 #include <sys/zio_checksum.h> 46 #include <sys/zio_compress.h> 47 #include <sys/sa.h> 48 #include <sys/zfeature.h> 49 #ifdef _KERNEL 50 #include <sys/vmsystm.h> 51 #include <sys/zfs_znode.h> 52 #endif 53 54 /* 55 * Enable/disable nopwrite feature. 56 */ 57 int zfs_nopwrite_enabled = 1; 58 59 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { 60 { DMU_BSWAP_UINT8, TRUE, "unallocated" }, 61 { DMU_BSWAP_ZAP, TRUE, "object directory" }, 62 { DMU_BSWAP_UINT64, TRUE, "object array" }, 63 { DMU_BSWAP_UINT8, TRUE, "packed nvlist" }, 64 { DMU_BSWAP_UINT64, TRUE, "packed nvlist size" }, 65 { DMU_BSWAP_UINT64, TRUE, "bpobj" }, 66 { DMU_BSWAP_UINT64, TRUE, "bpobj header" }, 67 { DMU_BSWAP_UINT64, TRUE, "SPA space map header" }, 68 { DMU_BSWAP_UINT64, TRUE, "SPA space map" }, 69 { DMU_BSWAP_UINT64, TRUE, "ZIL intent log" }, 70 { DMU_BSWAP_DNODE, TRUE, "DMU dnode" }, 71 { DMU_BSWAP_OBJSET, TRUE, "DMU objset" }, 72 { DMU_BSWAP_UINT64, TRUE, "DSL directory" }, 73 { DMU_BSWAP_ZAP, TRUE, "DSL directory child map"}, 74 { DMU_BSWAP_ZAP, TRUE, "DSL dataset snap map" }, 75 { DMU_BSWAP_ZAP, TRUE, "DSL props" }, 76 { DMU_BSWAP_UINT64, TRUE, "DSL dataset" }, 77 { DMU_BSWAP_ZNODE, TRUE, "ZFS znode" }, 78 { DMU_BSWAP_OLDACL, TRUE, "ZFS V0 ACL" }, 79 { DMU_BSWAP_UINT8, FALSE, "ZFS plain file" }, 80 { DMU_BSWAP_ZAP, TRUE, "ZFS directory" }, 81 { DMU_BSWAP_ZAP, TRUE, "ZFS master node" }, 82 { DMU_BSWAP_ZAP, TRUE, "ZFS delete queue" }, 83 { DMU_BSWAP_UINT8, FALSE, "zvol object" }, 84 { DMU_BSWAP_ZAP, TRUE, "zvol prop" }, 85 { DMU_BSWAP_UINT8, FALSE, "other uint8[]" }, 86 { DMU_BSWAP_UINT64, FALSE, "other uint64[]" }, 87 { DMU_BSWAP_ZAP, TRUE, "other ZAP" }, 88 { DMU_BSWAP_ZAP, TRUE, "persistent error log" }, 89 { DMU_BSWAP_UINT8, TRUE, "SPA history" }, 90 { DMU_BSWAP_UINT64, TRUE, "SPA history offsets" }, 91 { DMU_BSWAP_ZAP, TRUE, "Pool properties" }, 92 { DMU_BSWAP_ZAP, TRUE, "DSL permissions" }, 93 { DMU_BSWAP_ACL, TRUE, "ZFS ACL" }, 94 { DMU_BSWAP_UINT8, TRUE, "ZFS SYSACL" }, 95 { DMU_BSWAP_UINT8, TRUE, "FUID table" }, 96 { DMU_BSWAP_UINT64, TRUE, "FUID table size" }, 97 { DMU_BSWAP_ZAP, TRUE, "DSL dataset next clones"}, 98 { DMU_BSWAP_ZAP, TRUE, "scan work queue" }, 99 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group used" }, 100 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group quota" }, 101 { DMU_BSWAP_ZAP, TRUE, "snapshot refcount tags"}, 102 { DMU_BSWAP_ZAP, TRUE, "DDT ZAP algorithm" }, 103 { DMU_BSWAP_ZAP, TRUE, "DDT statistics" }, 104 { DMU_BSWAP_UINT8, TRUE, "System attributes" }, 105 { DMU_BSWAP_ZAP, TRUE, "SA master node" }, 106 { DMU_BSWAP_ZAP, TRUE, "SA attr registration" }, 107 { DMU_BSWAP_ZAP, TRUE, "SA attr layouts" }, 108 { DMU_BSWAP_ZAP, TRUE, "scan translations" }, 109 { DMU_BSWAP_UINT8, FALSE, "deduplicated block" }, 110 { DMU_BSWAP_ZAP, TRUE, "DSL deadlist map" }, 111 { DMU_BSWAP_UINT64, TRUE, "DSL deadlist map hdr" }, 112 { DMU_BSWAP_ZAP, TRUE, "DSL dir clones" }, 113 { DMU_BSWAP_UINT64, TRUE, "bpobj subobj" } 114 }; 115 116 const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = { 117 { byteswap_uint8_array, "uint8" }, 118 { byteswap_uint16_array, "uint16" }, 119 { byteswap_uint32_array, "uint32" }, 120 { byteswap_uint64_array, "uint64" }, 121 { zap_byteswap, "zap" }, 122 { dnode_buf_byteswap, "dnode" }, 123 { dmu_objset_byteswap, "objset" }, 124 { zfs_znode_byteswap, "znode" }, 125 { zfs_oldacl_byteswap, "oldacl" }, 126 { zfs_acl_byteswap, "acl" } 127 }; 128 129 int 130 dmu_buf_hold_noread(objset_t *os, uint64_t object, uint64_t offset, 131 void *tag, dmu_buf_t **dbp) 132 { 133 dnode_t *dn; 134 uint64_t blkid; 135 dmu_buf_impl_t *db; 136 int err; 137 138 err = dnode_hold(os, object, FTAG, &dn); 139 if (err) 140 return (err); 141 blkid = dbuf_whichblock(dn, offset); 142 rw_enter(&dn->dn_struct_rwlock, RW_READER); 143 db = dbuf_hold(dn, blkid, tag); 144 rw_exit(&dn->dn_struct_rwlock); 145 dnode_rele(dn, FTAG); 146 147 if (db == NULL) { 148 *dbp = NULL; 149 return (SET_ERROR(EIO)); 150 } 151 152 *dbp = &db->db; 153 return (err); 154 } 155 156 int 157 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 158 void *tag, dmu_buf_t **dbp, int flags) 159 { 160 int err; 161 int db_flags = DB_RF_CANFAIL; 162 163 if (flags & DMU_READ_NO_PREFETCH) 164 db_flags |= DB_RF_NOPREFETCH; 165 166 err = dmu_buf_hold_noread(os, object, offset, tag, dbp); 167 if (err == 0) { 168 dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp); 169 err = dbuf_read(db, NULL, db_flags); 170 if (err != 0) { 171 dbuf_rele(db, tag); 172 *dbp = NULL; 173 } 174 } 175 176 return (err); 177 } 178 179 int 180 dmu_bonus_max(void) 181 { 182 return (DN_MAX_BONUSLEN); 183 } 184 185 int 186 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx) 187 { 188 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 189 dnode_t *dn; 190 int error; 191 192 DB_DNODE_ENTER(db); 193 dn = DB_DNODE(db); 194 195 if (dn->dn_bonus != db) { 196 error = SET_ERROR(EINVAL); 197 } else if (newsize < 0 || newsize > db_fake->db_size) { 198 error = SET_ERROR(EINVAL); 199 } else { 200 dnode_setbonuslen(dn, newsize, tx); 201 error = 0; 202 } 203 204 DB_DNODE_EXIT(db); 205 return (error); 206 } 207 208 int 209 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx) 210 { 211 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 212 dnode_t *dn; 213 int error; 214 215 DB_DNODE_ENTER(db); 216 dn = DB_DNODE(db); 217 218 if (!DMU_OT_IS_VALID(type)) { 219 error = SET_ERROR(EINVAL); 220 } else if (dn->dn_bonus != db) { 221 error = SET_ERROR(EINVAL); 222 } else { 223 dnode_setbonus_type(dn, type, tx); 224 error = 0; 225 } 226 227 DB_DNODE_EXIT(db); 228 return (error); 229 } 230 231 dmu_object_type_t 232 dmu_get_bonustype(dmu_buf_t *db_fake) 233 { 234 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 235 dnode_t *dn; 236 dmu_object_type_t type; 237 238 DB_DNODE_ENTER(db); 239 dn = DB_DNODE(db); 240 type = dn->dn_bonustype; 241 DB_DNODE_EXIT(db); 242 243 return (type); 244 } 245 246 int 247 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx) 248 { 249 dnode_t *dn; 250 int error; 251 252 error = dnode_hold(os, object, FTAG, &dn); 253 dbuf_rm_spill(dn, tx); 254 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 255 dnode_rm_spill(dn, tx); 256 rw_exit(&dn->dn_struct_rwlock); 257 dnode_rele(dn, FTAG); 258 return (error); 259 } 260 261 /* 262 * returns ENOENT, EIO, or 0. 263 */ 264 int 265 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp) 266 { 267 dnode_t *dn; 268 dmu_buf_impl_t *db; 269 int error; 270 271 error = dnode_hold(os, object, FTAG, &dn); 272 if (error) 273 return (error); 274 275 rw_enter(&dn->dn_struct_rwlock, RW_READER); 276 if (dn->dn_bonus == NULL) { 277 rw_exit(&dn->dn_struct_rwlock); 278 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 279 if (dn->dn_bonus == NULL) 280 dbuf_create_bonus(dn); 281 } 282 db = dn->dn_bonus; 283 284 /* as long as the bonus buf is held, the dnode will be held */ 285 if (refcount_add(&db->db_holds, tag) == 1) { 286 VERIFY(dnode_add_ref(dn, db)); 287 atomic_inc_32(&dn->dn_dbufs_count); 288 } 289 290 /* 291 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's 292 * hold and incrementing the dbuf count to ensure that dnode_move() sees 293 * a dnode hold for every dbuf. 294 */ 295 rw_exit(&dn->dn_struct_rwlock); 296 297 dnode_rele(dn, FTAG); 298 299 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH)); 300 301 *dbp = &db->db; 302 return (0); 303 } 304 305 /* 306 * returns ENOENT, EIO, or 0. 307 * 308 * This interface will allocate a blank spill dbuf when a spill blk 309 * doesn't already exist on the dnode. 310 * 311 * if you only want to find an already existing spill db, then 312 * dmu_spill_hold_existing() should be used. 313 */ 314 int 315 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp) 316 { 317 dmu_buf_impl_t *db = NULL; 318 int err; 319 320 if ((flags & DB_RF_HAVESTRUCT) == 0) 321 rw_enter(&dn->dn_struct_rwlock, RW_READER); 322 323 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag); 324 325 if ((flags & DB_RF_HAVESTRUCT) == 0) 326 rw_exit(&dn->dn_struct_rwlock); 327 328 ASSERT(db != NULL); 329 err = dbuf_read(db, NULL, flags); 330 if (err == 0) 331 *dbp = &db->db; 332 else 333 dbuf_rele(db, tag); 334 return (err); 335 } 336 337 int 338 dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp) 339 { 340 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 341 dnode_t *dn; 342 int err; 343 344 DB_DNODE_ENTER(db); 345 dn = DB_DNODE(db); 346 347 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) { 348 err = SET_ERROR(EINVAL); 349 } else { 350 rw_enter(&dn->dn_struct_rwlock, RW_READER); 351 352 if (!dn->dn_have_spill) { 353 err = SET_ERROR(ENOENT); 354 } else { 355 err = dmu_spill_hold_by_dnode(dn, 356 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp); 357 } 358 359 rw_exit(&dn->dn_struct_rwlock); 360 } 361 362 DB_DNODE_EXIT(db); 363 return (err); 364 } 365 366 int 367 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp) 368 { 369 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 370 dnode_t *dn; 371 int err; 372 373 DB_DNODE_ENTER(db); 374 dn = DB_DNODE(db); 375 err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp); 376 DB_DNODE_EXIT(db); 377 378 return (err); 379 } 380 381 /* 382 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 383 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 384 * and can induce severe lock contention when writing to several files 385 * whose dnodes are in the same block. 386 */ 387 static int 388 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, 389 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags) 390 { 391 dmu_buf_t **dbp; 392 uint64_t blkid, nblks, i; 393 uint32_t dbuf_flags; 394 int err; 395 zio_t *zio; 396 397 ASSERT(length <= DMU_MAX_ACCESS); 398 399 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT; 400 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz) 401 dbuf_flags |= DB_RF_NOPREFETCH; 402 403 rw_enter(&dn->dn_struct_rwlock, RW_READER); 404 if (dn->dn_datablkshift) { 405 int blkshift = dn->dn_datablkshift; 406 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) - 407 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift; 408 } else { 409 if (offset + length > dn->dn_datablksz) { 410 zfs_panic_recover("zfs: accessing past end of object " 411 "%llx/%llx (size=%u access=%llu+%llu)", 412 (longlong_t)dn->dn_objset-> 413 os_dsl_dataset->ds_object, 414 (longlong_t)dn->dn_object, dn->dn_datablksz, 415 (longlong_t)offset, (longlong_t)length); 416 rw_exit(&dn->dn_struct_rwlock); 417 return (SET_ERROR(EIO)); 418 } 419 nblks = 1; 420 } 421 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 422 423 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); 424 blkid = dbuf_whichblock(dn, offset); 425 for (i = 0; i < nblks; i++) { 426 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 427 if (db == NULL) { 428 rw_exit(&dn->dn_struct_rwlock); 429 dmu_buf_rele_array(dbp, nblks, tag); 430 zio_nowait(zio); 431 return (SET_ERROR(EIO)); 432 } 433 /* initiate async i/o */ 434 if (read) { 435 (void) dbuf_read(db, zio, dbuf_flags); 436 } 437 dbp[i] = &db->db; 438 } 439 rw_exit(&dn->dn_struct_rwlock); 440 441 /* wait for async i/o */ 442 err = zio_wait(zio); 443 if (err) { 444 dmu_buf_rele_array(dbp, nblks, tag); 445 return (err); 446 } 447 448 /* wait for other io to complete */ 449 if (read) { 450 for (i = 0; i < nblks; i++) { 451 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 452 mutex_enter(&db->db_mtx); 453 while (db->db_state == DB_READ || 454 db->db_state == DB_FILL) 455 cv_wait(&db->db_changed, &db->db_mtx); 456 if (db->db_state == DB_UNCACHED) 457 err = SET_ERROR(EIO); 458 mutex_exit(&db->db_mtx); 459 if (err) { 460 dmu_buf_rele_array(dbp, nblks, tag); 461 return (err); 462 } 463 } 464 } 465 466 *numbufsp = nblks; 467 *dbpp = dbp; 468 return (0); 469 } 470 471 static int 472 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 473 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 474 { 475 dnode_t *dn; 476 int err; 477 478 err = dnode_hold(os, object, FTAG, &dn); 479 if (err) 480 return (err); 481 482 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 483 numbufsp, dbpp, DMU_READ_PREFETCH); 484 485 dnode_rele(dn, FTAG); 486 487 return (err); 488 } 489 490 int 491 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset, 492 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 493 { 494 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 495 dnode_t *dn; 496 int err; 497 498 DB_DNODE_ENTER(db); 499 dn = DB_DNODE(db); 500 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 501 numbufsp, dbpp, DMU_READ_PREFETCH); 502 DB_DNODE_EXIT(db); 503 504 return (err); 505 } 506 507 void 508 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) 509 { 510 int i; 511 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 512 513 if (numbufs == 0) 514 return; 515 516 for (i = 0; i < numbufs; i++) { 517 if (dbp[i]) 518 dbuf_rele(dbp[i], tag); 519 } 520 521 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 522 } 523 524 /* 525 * Issue prefetch i/os for the given blocks. 526 * 527 * Note: The assumption is that we *know* these blocks will be needed 528 * almost immediately. Therefore, the prefetch i/os will be issued at 529 * ZIO_PRIORITY_SYNC_READ 530 * 531 * Note: indirect blocks and other metadata will be read synchronously, 532 * causing this function to block if they are not already cached. 533 */ 534 void 535 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) 536 { 537 dnode_t *dn; 538 uint64_t blkid; 539 int nblks, err; 540 541 if (zfs_prefetch_disable) 542 return; 543 544 if (len == 0) { /* they're interested in the bonus buffer */ 545 dn = DMU_META_DNODE(os); 546 547 if (object == 0 || object >= DN_MAX_OBJECT) 548 return; 549 550 rw_enter(&dn->dn_struct_rwlock, RW_READER); 551 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); 552 dbuf_prefetch(dn, blkid, ZIO_PRIORITY_SYNC_READ); 553 rw_exit(&dn->dn_struct_rwlock); 554 return; 555 } 556 557 /* 558 * XXX - Note, if the dnode for the requested object is not 559 * already cached, we will do a *synchronous* read in the 560 * dnode_hold() call. The same is true for any indirects. 561 */ 562 err = dnode_hold(os, object, FTAG, &dn); 563 if (err != 0) 564 return; 565 566 rw_enter(&dn->dn_struct_rwlock, RW_READER); 567 if (dn->dn_datablkshift) { 568 int blkshift = dn->dn_datablkshift; 569 nblks = (P2ROUNDUP(offset + len, 1 << blkshift) - 570 P2ALIGN(offset, 1 << blkshift)) >> blkshift; 571 } else { 572 nblks = (offset < dn->dn_datablksz); 573 } 574 575 if (nblks != 0) { 576 blkid = dbuf_whichblock(dn, offset); 577 for (int i = 0; i < nblks; i++) 578 dbuf_prefetch(dn, blkid + i, ZIO_PRIORITY_SYNC_READ); 579 } 580 581 rw_exit(&dn->dn_struct_rwlock); 582 583 dnode_rele(dn, FTAG); 584 } 585 586 /* 587 * Get the next "chunk" of file data to free. We traverse the file from 588 * the end so that the file gets shorter over time (if we crashes in the 589 * middle, this will leave us in a better state). We find allocated file 590 * data by simply searching the allocated level 1 indirects. 591 * 592 * On input, *start should be the first offset that does not need to be 593 * freed (e.g. "offset + length"). On return, *start will be the first 594 * offset that should be freed. 595 */ 596 static int 597 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum) 598 { 599 uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1); 600 /* bytes of data covered by a level-1 indirect block */ 601 uint64_t iblkrange = 602 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 603 604 ASSERT3U(minimum, <=, *start); 605 606 if (*start - minimum <= iblkrange * maxblks) { 607 *start = minimum; 608 return (0); 609 } 610 ASSERT(ISP2(iblkrange)); 611 612 for (uint64_t blks = 0; *start > minimum && blks < maxblks; blks++) { 613 int err; 614 615 /* 616 * dnode_next_offset(BACKWARDS) will find an allocated L1 617 * indirect block at or before the input offset. We must 618 * decrement *start so that it is at the end of the region 619 * to search. 620 */ 621 (*start)--; 622 err = dnode_next_offset(dn, 623 DNODE_FIND_BACKWARDS, start, 2, 1, 0); 624 625 /* if there are no indirect blocks before start, we are done */ 626 if (err == ESRCH) { 627 *start = minimum; 628 break; 629 } else if (err != 0) { 630 return (err); 631 } 632 633 /* set start to the beginning of this L1 indirect */ 634 *start = P2ALIGN(*start, iblkrange); 635 } 636 if (*start < minimum) 637 *start = minimum; 638 return (0); 639 } 640 641 static int 642 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 643 uint64_t length) 644 { 645 uint64_t object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 646 int err; 647 648 if (offset >= object_size) 649 return (0); 650 651 if (length == DMU_OBJECT_END || offset + length > object_size) 652 length = object_size - offset; 653 654 while (length != 0) { 655 uint64_t chunk_end, chunk_begin; 656 657 chunk_end = chunk_begin = offset + length; 658 659 /* move chunk_begin backwards to the beginning of this chunk */ 660 err = get_next_chunk(dn, &chunk_begin, offset); 661 if (err) 662 return (err); 663 ASSERT3U(chunk_begin, >=, offset); 664 ASSERT3U(chunk_begin, <=, chunk_end); 665 666 dmu_tx_t *tx = dmu_tx_create(os); 667 dmu_tx_hold_free(tx, dn->dn_object, 668 chunk_begin, chunk_end - chunk_begin); 669 670 /* 671 * Mark this transaction as typically resulting in a net 672 * reduction in space used. 673 */ 674 dmu_tx_mark_netfree(tx); 675 err = dmu_tx_assign(tx, TXG_WAIT); 676 if (err) { 677 dmu_tx_abort(tx); 678 return (err); 679 } 680 dnode_free_range(dn, chunk_begin, chunk_end - chunk_begin, tx); 681 dmu_tx_commit(tx); 682 683 length -= chunk_end - chunk_begin; 684 } 685 return (0); 686 } 687 688 int 689 dmu_free_long_range(objset_t *os, uint64_t object, 690 uint64_t offset, uint64_t length) 691 { 692 dnode_t *dn; 693 int err; 694 695 err = dnode_hold(os, object, FTAG, &dn); 696 if (err != 0) 697 return (err); 698 err = dmu_free_long_range_impl(os, dn, offset, length); 699 700 /* 701 * It is important to zero out the maxblkid when freeing the entire 702 * file, so that (a) subsequent calls to dmu_free_long_range_impl() 703 * will take the fast path, and (b) dnode_reallocate() can verify 704 * that the entire file has been freed. 705 */ 706 if (err == 0 && offset == 0 && length == DMU_OBJECT_END) 707 dn->dn_maxblkid = 0; 708 709 dnode_rele(dn, FTAG); 710 return (err); 711 } 712 713 int 714 dmu_free_long_object(objset_t *os, uint64_t object) 715 { 716 dmu_tx_t *tx; 717 int err; 718 719 err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END); 720 if (err != 0) 721 return (err); 722 723 tx = dmu_tx_create(os); 724 dmu_tx_hold_bonus(tx, object); 725 dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END); 726 dmu_tx_mark_netfree(tx); 727 err = dmu_tx_assign(tx, TXG_WAIT); 728 if (err == 0) { 729 err = dmu_object_free(os, object, tx); 730 dmu_tx_commit(tx); 731 } else { 732 dmu_tx_abort(tx); 733 } 734 735 return (err); 736 } 737 738 int 739 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 740 uint64_t size, dmu_tx_t *tx) 741 { 742 dnode_t *dn; 743 int err = dnode_hold(os, object, FTAG, &dn); 744 if (err) 745 return (err); 746 ASSERT(offset < UINT64_MAX); 747 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 748 dnode_free_range(dn, offset, size, tx); 749 dnode_rele(dn, FTAG); 750 return (0); 751 } 752 753 int 754 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 755 void *buf, uint32_t flags) 756 { 757 dnode_t *dn; 758 dmu_buf_t **dbp; 759 int numbufs, err; 760 761 err = dnode_hold(os, object, FTAG, &dn); 762 if (err) 763 return (err); 764 765 /* 766 * Deal with odd block sizes, where there can't be data past the first 767 * block. If we ever do the tail block optimization, we will need to 768 * handle that here as well. 769 */ 770 if (dn->dn_maxblkid == 0) { 771 int newsz = offset > dn->dn_datablksz ? 0 : 772 MIN(size, dn->dn_datablksz - offset); 773 bzero((char *)buf + newsz, size - newsz); 774 size = newsz; 775 } 776 777 while (size > 0) { 778 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 779 int i; 780 781 /* 782 * NB: we could do this block-at-a-time, but it's nice 783 * to be reading in parallel. 784 */ 785 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 786 TRUE, FTAG, &numbufs, &dbp, flags); 787 if (err) 788 break; 789 790 for (i = 0; i < numbufs; i++) { 791 int tocpy; 792 int bufoff; 793 dmu_buf_t *db = dbp[i]; 794 795 ASSERT(size > 0); 796 797 bufoff = offset - db->db_offset; 798 tocpy = (int)MIN(db->db_size - bufoff, size); 799 800 bcopy((char *)db->db_data + bufoff, buf, tocpy); 801 802 offset += tocpy; 803 size -= tocpy; 804 buf = (char *)buf + tocpy; 805 } 806 dmu_buf_rele_array(dbp, numbufs, FTAG); 807 } 808 dnode_rele(dn, FTAG); 809 return (err); 810 } 811 812 void 813 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 814 const void *buf, dmu_tx_t *tx) 815 { 816 dmu_buf_t **dbp; 817 int numbufs, i; 818 819 if (size == 0) 820 return; 821 822 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 823 FALSE, FTAG, &numbufs, &dbp)); 824 825 for (i = 0; i < numbufs; i++) { 826 int tocpy; 827 int bufoff; 828 dmu_buf_t *db = dbp[i]; 829 830 ASSERT(size > 0); 831 832 bufoff = offset - db->db_offset; 833 tocpy = (int)MIN(db->db_size - bufoff, size); 834 835 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 836 837 if (tocpy == db->db_size) 838 dmu_buf_will_fill(db, tx); 839 else 840 dmu_buf_will_dirty(db, tx); 841 842 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 843 844 if (tocpy == db->db_size) 845 dmu_buf_fill_done(db, tx); 846 847 offset += tocpy; 848 size -= tocpy; 849 buf = (char *)buf + tocpy; 850 } 851 dmu_buf_rele_array(dbp, numbufs, FTAG); 852 } 853 854 void 855 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 856 dmu_tx_t *tx) 857 { 858 dmu_buf_t **dbp; 859 int numbufs, i; 860 861 if (size == 0) 862 return; 863 864 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 865 FALSE, FTAG, &numbufs, &dbp)); 866 867 for (i = 0; i < numbufs; i++) { 868 dmu_buf_t *db = dbp[i]; 869 870 dmu_buf_will_not_fill(db, tx); 871 } 872 dmu_buf_rele_array(dbp, numbufs, FTAG); 873 } 874 875 void 876 dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset, 877 void *data, uint8_t etype, uint8_t comp, int uncompressed_size, 878 int compressed_size, int byteorder, dmu_tx_t *tx) 879 { 880 dmu_buf_t *db; 881 882 ASSERT3U(etype, <, NUM_BP_EMBEDDED_TYPES); 883 ASSERT3U(comp, <, ZIO_COMPRESS_FUNCTIONS); 884 VERIFY0(dmu_buf_hold_noread(os, object, offset, 885 FTAG, &db)); 886 887 dmu_buf_write_embedded(db, 888 data, (bp_embedded_type_t)etype, (enum zio_compress)comp, 889 uncompressed_size, compressed_size, byteorder, tx); 890 891 dmu_buf_rele(db, FTAG); 892 } 893 894 /* 895 * DMU support for xuio 896 */ 897 kstat_t *xuio_ksp = NULL; 898 899 int 900 dmu_xuio_init(xuio_t *xuio, int nblk) 901 { 902 dmu_xuio_t *priv; 903 uio_t *uio = &xuio->xu_uio; 904 905 uio->uio_iovcnt = nblk; 906 uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_SLEEP); 907 908 priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP); 909 priv->cnt = nblk; 910 priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP); 911 priv->iovp = uio->uio_iov; 912 XUIO_XUZC_PRIV(xuio) = priv; 913 914 if (XUIO_XUZC_RW(xuio) == UIO_READ) 915 XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk); 916 else 917 XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk); 918 919 return (0); 920 } 921 922 void 923 dmu_xuio_fini(xuio_t *xuio) 924 { 925 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 926 int nblk = priv->cnt; 927 928 kmem_free(priv->iovp, nblk * sizeof (iovec_t)); 929 kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *)); 930 kmem_free(priv, sizeof (dmu_xuio_t)); 931 932 if (XUIO_XUZC_RW(xuio) == UIO_READ) 933 XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk); 934 else 935 XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk); 936 } 937 938 /* 939 * Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf } 940 * and increase priv->next by 1. 941 */ 942 int 943 dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n) 944 { 945 struct iovec *iov; 946 uio_t *uio = &xuio->xu_uio; 947 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 948 int i = priv->next++; 949 950 ASSERT(i < priv->cnt); 951 ASSERT(off + n <= arc_buf_size(abuf)); 952 iov = uio->uio_iov + i; 953 iov->iov_base = (char *)abuf->b_data + off; 954 iov->iov_len = n; 955 priv->bufs[i] = abuf; 956 return (0); 957 } 958 959 int 960 dmu_xuio_cnt(xuio_t *xuio) 961 { 962 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 963 return (priv->cnt); 964 } 965 966 arc_buf_t * 967 dmu_xuio_arcbuf(xuio_t *xuio, int i) 968 { 969 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 970 971 ASSERT(i < priv->cnt); 972 return (priv->bufs[i]); 973 } 974 975 void 976 dmu_xuio_clear(xuio_t *xuio, int i) 977 { 978 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 979 980 ASSERT(i < priv->cnt); 981 priv->bufs[i] = NULL; 982 } 983 984 static void 985 xuio_stat_init(void) 986 { 987 xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc", 988 KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t), 989 KSTAT_FLAG_VIRTUAL); 990 if (xuio_ksp != NULL) { 991 xuio_ksp->ks_data = &xuio_stats; 992 kstat_install(xuio_ksp); 993 } 994 } 995 996 static void 997 xuio_stat_fini(void) 998 { 999 if (xuio_ksp != NULL) { 1000 kstat_delete(xuio_ksp); 1001 xuio_ksp = NULL; 1002 } 1003 } 1004 1005 void 1006 xuio_stat_wbuf_copied() 1007 { 1008 XUIOSTAT_BUMP(xuiostat_wbuf_copied); 1009 } 1010 1011 void 1012 xuio_stat_wbuf_nocopy() 1013 { 1014 XUIOSTAT_BUMP(xuiostat_wbuf_nocopy); 1015 } 1016 1017 #ifdef _KERNEL 1018 int 1019 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size) 1020 { 1021 dmu_buf_t **dbp; 1022 int numbufs, i, err; 1023 xuio_t *xuio = NULL; 1024 1025 /* 1026 * NB: we could do this block-at-a-time, but it's nice 1027 * to be reading in parallel. 1028 */ 1029 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG, 1030 &numbufs, &dbp); 1031 if (err) 1032 return (err); 1033 1034 if (uio->uio_extflg == UIO_XUIO) 1035 xuio = (xuio_t *)uio; 1036 1037 for (i = 0; i < numbufs; i++) { 1038 int tocpy; 1039 int bufoff; 1040 dmu_buf_t *db = dbp[i]; 1041 1042 ASSERT(size > 0); 1043 1044 bufoff = uio->uio_loffset - db->db_offset; 1045 tocpy = (int)MIN(db->db_size - bufoff, size); 1046 1047 if (xuio) { 1048 dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db; 1049 arc_buf_t *dbuf_abuf = dbi->db_buf; 1050 arc_buf_t *abuf = dbuf_loan_arcbuf(dbi); 1051 err = dmu_xuio_add(xuio, abuf, bufoff, tocpy); 1052 if (!err) { 1053 uio->uio_resid -= tocpy; 1054 uio->uio_loffset += tocpy; 1055 } 1056 1057 if (abuf == dbuf_abuf) 1058 XUIOSTAT_BUMP(xuiostat_rbuf_nocopy); 1059 else 1060 XUIOSTAT_BUMP(xuiostat_rbuf_copied); 1061 } else { 1062 err = uiomove((char *)db->db_data + bufoff, tocpy, 1063 UIO_READ, uio); 1064 } 1065 if (err) 1066 break; 1067 1068 size -= tocpy; 1069 } 1070 dmu_buf_rele_array(dbp, numbufs, FTAG); 1071 1072 return (err); 1073 } 1074 1075 static int 1076 dmu_write_uio_dnode(dnode_t *dn, uio_t *uio, uint64_t size, dmu_tx_t *tx) 1077 { 1078 dmu_buf_t **dbp; 1079 int numbufs; 1080 int err = 0; 1081 int i; 1082 1083 err = dmu_buf_hold_array_by_dnode(dn, uio->uio_loffset, size, 1084 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH); 1085 if (err) 1086 return (err); 1087 1088 for (i = 0; i < numbufs; i++) { 1089 int tocpy; 1090 int bufoff; 1091 dmu_buf_t *db = dbp[i]; 1092 1093 ASSERT(size > 0); 1094 1095 bufoff = uio->uio_loffset - db->db_offset; 1096 tocpy = (int)MIN(db->db_size - bufoff, size); 1097 1098 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1099 1100 if (tocpy == db->db_size) 1101 dmu_buf_will_fill(db, tx); 1102 else 1103 dmu_buf_will_dirty(db, tx); 1104 1105 /* 1106 * XXX uiomove could block forever (eg. nfs-backed 1107 * pages). There needs to be a uiolockdown() function 1108 * to lock the pages in memory, so that uiomove won't 1109 * block. 1110 */ 1111 err = uiomove((char *)db->db_data + bufoff, tocpy, 1112 UIO_WRITE, uio); 1113 1114 if (tocpy == db->db_size) 1115 dmu_buf_fill_done(db, tx); 1116 1117 if (err) 1118 break; 1119 1120 size -= tocpy; 1121 } 1122 1123 dmu_buf_rele_array(dbp, numbufs, FTAG); 1124 return (err); 1125 } 1126 1127 int 1128 dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size, 1129 dmu_tx_t *tx) 1130 { 1131 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1132 dnode_t *dn; 1133 int err; 1134 1135 if (size == 0) 1136 return (0); 1137 1138 DB_DNODE_ENTER(db); 1139 dn = DB_DNODE(db); 1140 err = dmu_write_uio_dnode(dn, uio, size, tx); 1141 DB_DNODE_EXIT(db); 1142 1143 return (err); 1144 } 1145 1146 int 1147 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size, 1148 dmu_tx_t *tx) 1149 { 1150 dnode_t *dn; 1151 int err; 1152 1153 if (size == 0) 1154 return (0); 1155 1156 err = dnode_hold(os, object, FTAG, &dn); 1157 if (err) 1158 return (err); 1159 1160 err = dmu_write_uio_dnode(dn, uio, size, tx); 1161 1162 dnode_rele(dn, FTAG); 1163 1164 return (err); 1165 } 1166 1167 int 1168 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1169 page_t *pp, dmu_tx_t *tx) 1170 { 1171 dmu_buf_t **dbp; 1172 int numbufs, i; 1173 int err; 1174 1175 if (size == 0) 1176 return (0); 1177 1178 err = dmu_buf_hold_array(os, object, offset, size, 1179 FALSE, FTAG, &numbufs, &dbp); 1180 if (err) 1181 return (err); 1182 1183 for (i = 0; i < numbufs; i++) { 1184 int tocpy, copied, thiscpy; 1185 int bufoff; 1186 dmu_buf_t *db = dbp[i]; 1187 caddr_t va; 1188 1189 ASSERT(size > 0); 1190 ASSERT3U(db->db_size, >=, PAGESIZE); 1191 1192 bufoff = offset - db->db_offset; 1193 tocpy = (int)MIN(db->db_size - bufoff, size); 1194 1195 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1196 1197 if (tocpy == db->db_size) 1198 dmu_buf_will_fill(db, tx); 1199 else 1200 dmu_buf_will_dirty(db, tx); 1201 1202 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 1203 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 1204 thiscpy = MIN(PAGESIZE, tocpy - copied); 1205 va = zfs_map_page(pp, S_READ); 1206 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 1207 zfs_unmap_page(pp, va); 1208 pp = pp->p_next; 1209 bufoff += PAGESIZE; 1210 } 1211 1212 if (tocpy == db->db_size) 1213 dmu_buf_fill_done(db, tx); 1214 1215 offset += tocpy; 1216 size -= tocpy; 1217 } 1218 dmu_buf_rele_array(dbp, numbufs, FTAG); 1219 return (err); 1220 } 1221 #endif 1222 1223 /* 1224 * Allocate a loaned anonymous arc buffer. 1225 */ 1226 arc_buf_t * 1227 dmu_request_arcbuf(dmu_buf_t *handle, int size) 1228 { 1229 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle; 1230 1231 return (arc_loan_buf(db->db_objset->os_spa, size)); 1232 } 1233 1234 /* 1235 * Free a loaned arc buffer. 1236 */ 1237 void 1238 dmu_return_arcbuf(arc_buf_t *buf) 1239 { 1240 arc_return_buf(buf, FTAG); 1241 VERIFY(arc_buf_remove_ref(buf, FTAG)); 1242 } 1243 1244 /* 1245 * When possible directly assign passed loaned arc buffer to a dbuf. 1246 * If this is not possible copy the contents of passed arc buf via 1247 * dmu_write(). 1248 */ 1249 void 1250 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 1251 dmu_tx_t *tx) 1252 { 1253 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle; 1254 dnode_t *dn; 1255 dmu_buf_impl_t *db; 1256 uint32_t blksz = (uint32_t)arc_buf_size(buf); 1257 uint64_t blkid; 1258 1259 DB_DNODE_ENTER(dbuf); 1260 dn = DB_DNODE(dbuf); 1261 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1262 blkid = dbuf_whichblock(dn, offset); 1263 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL); 1264 rw_exit(&dn->dn_struct_rwlock); 1265 DB_DNODE_EXIT(dbuf); 1266 1267 /* 1268 * We can only assign if the offset is aligned, the arc buf is the 1269 * same size as the dbuf, and the dbuf is not metadata. It 1270 * can't be metadata because the loaned arc buf comes from the 1271 * user-data kmem arena. 1272 */ 1273 if (offset == db->db.db_offset && blksz == db->db.db_size && 1274 DBUF_GET_BUFC_TYPE(db) == ARC_BUFC_DATA) { 1275 dbuf_assign_arcbuf(db, buf, tx); 1276 dbuf_rele(db, FTAG); 1277 } else { 1278 objset_t *os; 1279 uint64_t object; 1280 1281 DB_DNODE_ENTER(dbuf); 1282 dn = DB_DNODE(dbuf); 1283 os = dn->dn_objset; 1284 object = dn->dn_object; 1285 DB_DNODE_EXIT(dbuf); 1286 1287 dbuf_rele(db, FTAG); 1288 dmu_write(os, object, offset, blksz, buf->b_data, tx); 1289 dmu_return_arcbuf(buf); 1290 XUIOSTAT_BUMP(xuiostat_wbuf_copied); 1291 } 1292 } 1293 1294 typedef struct { 1295 dbuf_dirty_record_t *dsa_dr; 1296 dmu_sync_cb_t *dsa_done; 1297 zgd_t *dsa_zgd; 1298 dmu_tx_t *dsa_tx; 1299 } dmu_sync_arg_t; 1300 1301 /* ARGSUSED */ 1302 static void 1303 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 1304 { 1305 dmu_sync_arg_t *dsa = varg; 1306 dmu_buf_t *db = dsa->dsa_zgd->zgd_db; 1307 blkptr_t *bp = zio->io_bp; 1308 1309 if (zio->io_error == 0) { 1310 if (BP_IS_HOLE(bp)) { 1311 /* 1312 * A block of zeros may compress to a hole, but the 1313 * block size still needs to be known for replay. 1314 */ 1315 BP_SET_LSIZE(bp, db->db_size); 1316 } else if (!BP_IS_EMBEDDED(bp)) { 1317 ASSERT(BP_GET_LEVEL(bp) == 0); 1318 bp->blk_fill = 1; 1319 } 1320 } 1321 } 1322 1323 static void 1324 dmu_sync_late_arrival_ready(zio_t *zio) 1325 { 1326 dmu_sync_ready(zio, NULL, zio->io_private); 1327 } 1328 1329 /* ARGSUSED */ 1330 static void 1331 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 1332 { 1333 dmu_sync_arg_t *dsa = varg; 1334 dbuf_dirty_record_t *dr = dsa->dsa_dr; 1335 dmu_buf_impl_t *db = dr->dr_dbuf; 1336 1337 mutex_enter(&db->db_mtx); 1338 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 1339 if (zio->io_error == 0) { 1340 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE); 1341 if (dr->dt.dl.dr_nopwrite) { 1342 blkptr_t *bp = zio->io_bp; 1343 blkptr_t *bp_orig = &zio->io_bp_orig; 1344 uint8_t chksum = BP_GET_CHECKSUM(bp_orig); 1345 1346 ASSERT(BP_EQUAL(bp, bp_orig)); 1347 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF); 1348 ASSERT(zio_checksum_table[chksum].ci_dedup); 1349 } 1350 dr->dt.dl.dr_overridden_by = *zio->io_bp; 1351 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 1352 dr->dt.dl.dr_copies = zio->io_prop.zp_copies; 1353 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by)) 1354 BP_ZERO(&dr->dt.dl.dr_overridden_by); 1355 } else { 1356 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; 1357 } 1358 cv_broadcast(&db->db_changed); 1359 mutex_exit(&db->db_mtx); 1360 1361 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1362 1363 kmem_free(dsa, sizeof (*dsa)); 1364 } 1365 1366 static void 1367 dmu_sync_late_arrival_done(zio_t *zio) 1368 { 1369 blkptr_t *bp = zio->io_bp; 1370 dmu_sync_arg_t *dsa = zio->io_private; 1371 blkptr_t *bp_orig = &zio->io_bp_orig; 1372 1373 if (zio->io_error == 0 && !BP_IS_HOLE(bp)) { 1374 /* 1375 * If we didn't allocate a new block (i.e. ZIO_FLAG_NOPWRITE) 1376 * then there is nothing to do here. Otherwise, free the 1377 * newly allocated block in this txg. 1378 */ 1379 if (zio->io_flags & ZIO_FLAG_NOPWRITE) { 1380 ASSERT(BP_EQUAL(bp, bp_orig)); 1381 } else { 1382 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig)); 1383 ASSERT(zio->io_bp->blk_birth == zio->io_txg); 1384 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa)); 1385 zio_free(zio->io_spa, zio->io_txg, zio->io_bp); 1386 } 1387 } 1388 1389 dmu_tx_commit(dsa->dsa_tx); 1390 1391 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1392 1393 kmem_free(dsa, sizeof (*dsa)); 1394 } 1395 1396 static int 1397 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, 1398 zio_prop_t *zp, zbookmark_phys_t *zb) 1399 { 1400 dmu_sync_arg_t *dsa; 1401 dmu_tx_t *tx; 1402 1403 tx = dmu_tx_create(os); 1404 dmu_tx_hold_space(tx, zgd->zgd_db->db_size); 1405 if (dmu_tx_assign(tx, TXG_WAIT) != 0) { 1406 dmu_tx_abort(tx); 1407 /* Make zl_get_data do txg_waited_synced() */ 1408 return (SET_ERROR(EIO)); 1409 } 1410 1411 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1412 dsa->dsa_dr = NULL; 1413 dsa->dsa_done = done; 1414 dsa->dsa_zgd = zgd; 1415 dsa->dsa_tx = tx; 1416 1417 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, 1418 zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp, 1419 dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, dsa, 1420 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb)); 1421 1422 return (0); 1423 } 1424 1425 /* 1426 * Intent log support: sync the block associated with db to disk. 1427 * N.B. and XXX: the caller is responsible for making sure that the 1428 * data isn't changing while dmu_sync() is writing it. 1429 * 1430 * Return values: 1431 * 1432 * EEXIST: this txg has already been synced, so there's nothing to do. 1433 * The caller should not log the write. 1434 * 1435 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 1436 * The caller should not log the write. 1437 * 1438 * EALREADY: this block is already in the process of being synced. 1439 * The caller should track its progress (somehow). 1440 * 1441 * EIO: could not do the I/O. 1442 * The caller should do a txg_wait_synced(). 1443 * 1444 * 0: the I/O has been initiated. 1445 * The caller should log this blkptr in the done callback. 1446 * It is possible that the I/O will fail, in which case 1447 * the error will be reported to the done callback and 1448 * propagated to pio from zio_done(). 1449 */ 1450 int 1451 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) 1452 { 1453 blkptr_t *bp = zgd->zgd_bp; 1454 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db; 1455 objset_t *os = db->db_objset; 1456 dsl_dataset_t *ds = os->os_dsl_dataset; 1457 dbuf_dirty_record_t *dr; 1458 dmu_sync_arg_t *dsa; 1459 zbookmark_phys_t zb; 1460 zio_prop_t zp; 1461 dnode_t *dn; 1462 1463 ASSERT(pio != NULL); 1464 ASSERT(txg != 0); 1465 1466 SET_BOOKMARK(&zb, ds->ds_object, 1467 db->db.db_object, db->db_level, db->db_blkid); 1468 1469 DB_DNODE_ENTER(db); 1470 dn = DB_DNODE(db); 1471 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp); 1472 DB_DNODE_EXIT(db); 1473 1474 /* 1475 * If we're frozen (running ziltest), we always need to generate a bp. 1476 */ 1477 if (txg > spa_freeze_txg(os->os_spa)) 1478 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1479 1480 /* 1481 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf() 1482 * and us. If we determine that this txg is not yet syncing, 1483 * but it begins to sync a moment later, that's OK because the 1484 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx. 1485 */ 1486 mutex_enter(&db->db_mtx); 1487 1488 if (txg <= spa_last_synced_txg(os->os_spa)) { 1489 /* 1490 * This txg has already synced. There's nothing to do. 1491 */ 1492 mutex_exit(&db->db_mtx); 1493 return (SET_ERROR(EEXIST)); 1494 } 1495 1496 if (txg <= spa_syncing_txg(os->os_spa)) { 1497 /* 1498 * This txg is currently syncing, so we can't mess with 1499 * the dirty record anymore; just write a new log block. 1500 */ 1501 mutex_exit(&db->db_mtx); 1502 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1503 } 1504 1505 dr = db->db_last_dirty; 1506 while (dr && dr->dr_txg != txg) 1507 dr = dr->dr_next; 1508 1509 if (dr == NULL) { 1510 /* 1511 * There's no dr for this dbuf, so it must have been freed. 1512 * There's no need to log writes to freed blocks, so we're done. 1513 */ 1514 mutex_exit(&db->db_mtx); 1515 return (SET_ERROR(ENOENT)); 1516 } 1517 1518 ASSERT(dr->dr_next == NULL || dr->dr_next->dr_txg < txg); 1519 1520 /* 1521 * Assume the on-disk data is X, the current syncing data is Y, 1522 * and the current in-memory data is Z (currently in dmu_sync). 1523 * X and Z are identical but Y is has been modified. Normally, 1524 * when X and Z are the same we will perform a nopwrite but if Y 1525 * is different we must disable nopwrite since the resulting write 1526 * of Y to disk can free the block containing X. If we allowed a 1527 * nopwrite to occur the block pointing to Z would reference a freed 1528 * block. Since this is a rare case we simplify this by disabling 1529 * nopwrite if the current dmu_sync-ing dbuf has been modified in 1530 * a previous transaction. 1531 */ 1532 if (dr->dr_next) 1533 zp.zp_nopwrite = B_FALSE; 1534 1535 ASSERT(dr->dr_txg == txg); 1536 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC || 1537 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1538 /* 1539 * We have already issued a sync write for this buffer, 1540 * or this buffer has already been synced. It could not 1541 * have been dirtied since, or we would have cleared the state. 1542 */ 1543 mutex_exit(&db->db_mtx); 1544 return (SET_ERROR(EALREADY)); 1545 } 1546 1547 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); 1548 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1549 mutex_exit(&db->db_mtx); 1550 1551 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1552 dsa->dsa_dr = dr; 1553 dsa->dsa_done = done; 1554 dsa->dsa_zgd = zgd; 1555 dsa->dsa_tx = NULL; 1556 1557 zio_nowait(arc_write(pio, os->os_spa, txg, 1558 bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db), 1559 DBUF_IS_L2COMPRESSIBLE(db), &zp, dmu_sync_ready, 1560 NULL, dmu_sync_done, dsa, ZIO_PRIORITY_SYNC_WRITE, 1561 ZIO_FLAG_CANFAIL, &zb)); 1562 1563 return (0); 1564 } 1565 1566 int 1567 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1568 dmu_tx_t *tx) 1569 { 1570 dnode_t *dn; 1571 int err; 1572 1573 err = dnode_hold(os, object, FTAG, &dn); 1574 if (err) 1575 return (err); 1576 err = dnode_set_blksz(dn, size, ibs, tx); 1577 dnode_rele(dn, FTAG); 1578 return (err); 1579 } 1580 1581 void 1582 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1583 dmu_tx_t *tx) 1584 { 1585 dnode_t *dn; 1586 1587 /* 1588 * Send streams include each object's checksum function. This 1589 * check ensures that the receiving system can understand the 1590 * checksum function transmitted. 1591 */ 1592 ASSERT3U(checksum, <, ZIO_CHECKSUM_LEGACY_FUNCTIONS); 1593 1594 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1595 ASSERT3U(checksum, <, ZIO_CHECKSUM_FUNCTIONS); 1596 dn->dn_checksum = checksum; 1597 dnode_setdirty(dn, tx); 1598 dnode_rele(dn, FTAG); 1599 } 1600 1601 void 1602 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1603 dmu_tx_t *tx) 1604 { 1605 dnode_t *dn; 1606 1607 /* 1608 * Send streams include each object's compression function. This 1609 * check ensures that the receiving system can understand the 1610 * compression function transmitted. 1611 */ 1612 ASSERT3U(compress, <, ZIO_COMPRESS_LEGACY_FUNCTIONS); 1613 1614 VERIFY0(dnode_hold(os, object, FTAG, &dn)); 1615 dn->dn_compress = compress; 1616 dnode_setdirty(dn, tx); 1617 dnode_rele(dn, FTAG); 1618 } 1619 1620 int zfs_mdcomp_disable = 0; 1621 1622 /* 1623 * When the "redundant_metadata" property is set to "most", only indirect 1624 * blocks of this level and higher will have an additional ditto block. 1625 */ 1626 int zfs_redundant_metadata_most_ditto_level = 2; 1627 1628 void 1629 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp) 1630 { 1631 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET; 1632 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) || 1633 (wp & WP_SPILL)); 1634 enum zio_checksum checksum = os->os_checksum; 1635 enum zio_compress compress = os->os_compress; 1636 enum zio_checksum dedup_checksum = os->os_dedup_checksum; 1637 boolean_t dedup = B_FALSE; 1638 boolean_t nopwrite = B_FALSE; 1639 boolean_t dedup_verify = os->os_dedup_verify; 1640 int copies = os->os_copies; 1641 1642 /* 1643 * We maintain different write policies for each of the following 1644 * types of data: 1645 * 1. metadata 1646 * 2. preallocated blocks (i.e. level-0 blocks of a dump device) 1647 * 3. all other level 0 blocks 1648 */ 1649 if (ismd) { 1650 /* 1651 * XXX -- we should design a compression algorithm 1652 * that specializes in arrays of bps. 1653 */ 1654 boolean_t lz4_ac = spa_feature_is_active(os->os_spa, 1655 SPA_FEATURE_LZ4_COMPRESS); 1656 1657 if (zfs_mdcomp_disable) { 1658 compress = ZIO_COMPRESS_EMPTY; 1659 } else if (lz4_ac) { 1660 compress = ZIO_COMPRESS_LZ4; 1661 } else { 1662 compress = ZIO_COMPRESS_LZJB; 1663 } 1664 1665 /* 1666 * Metadata always gets checksummed. If the data 1667 * checksum is multi-bit correctable, and it's not a 1668 * ZBT-style checksum, then it's suitable for metadata 1669 * as well. Otherwise, the metadata checksum defaults 1670 * to fletcher4. 1671 */ 1672 if (zio_checksum_table[checksum].ci_correctable < 1 || 1673 zio_checksum_table[checksum].ci_eck) 1674 checksum = ZIO_CHECKSUM_FLETCHER_4; 1675 1676 if (os->os_redundant_metadata == ZFS_REDUNDANT_METADATA_ALL || 1677 (os->os_redundant_metadata == 1678 ZFS_REDUNDANT_METADATA_MOST && 1679 (level >= zfs_redundant_metadata_most_ditto_level || 1680 DMU_OT_IS_METADATA(type) || (wp & WP_SPILL)))) 1681 copies++; 1682 } else if (wp & WP_NOFILL) { 1683 ASSERT(level == 0); 1684 1685 /* 1686 * If we're writing preallocated blocks, we aren't actually 1687 * writing them so don't set any policy properties. These 1688 * blocks are currently only used by an external subsystem 1689 * outside of zfs (i.e. dump) and not written by the zio 1690 * pipeline. 1691 */ 1692 compress = ZIO_COMPRESS_OFF; 1693 checksum = ZIO_CHECKSUM_NOPARITY; 1694 } else { 1695 compress = zio_compress_select(dn->dn_compress, compress); 1696 1697 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ? 1698 zio_checksum_select(dn->dn_checksum, checksum) : 1699 dedup_checksum; 1700 1701 /* 1702 * Determine dedup setting. If we are in dmu_sync(), 1703 * we won't actually dedup now because that's all 1704 * done in syncing context; but we do want to use the 1705 * dedup checkum. If the checksum is not strong 1706 * enough to ensure unique signatures, force 1707 * dedup_verify. 1708 */ 1709 if (dedup_checksum != ZIO_CHECKSUM_OFF) { 1710 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE; 1711 if (!zio_checksum_table[checksum].ci_dedup) 1712 dedup_verify = B_TRUE; 1713 } 1714 1715 /* 1716 * Enable nopwrite if we have a cryptographically secure 1717 * checksum that has no known collisions (i.e. SHA-256) 1718 * and compression is enabled. We don't enable nopwrite if 1719 * dedup is enabled as the two features are mutually exclusive. 1720 */ 1721 nopwrite = (!dedup && zio_checksum_table[checksum].ci_dedup && 1722 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled); 1723 } 1724 1725 zp->zp_checksum = checksum; 1726 zp->zp_compress = compress; 1727 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type; 1728 zp->zp_level = level; 1729 zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa)); 1730 zp->zp_dedup = dedup; 1731 zp->zp_dedup_verify = dedup && dedup_verify; 1732 zp->zp_nopwrite = nopwrite; 1733 } 1734 1735 int 1736 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 1737 { 1738 dnode_t *dn; 1739 int i, err; 1740 1741 err = dnode_hold(os, object, FTAG, &dn); 1742 if (err) 1743 return (err); 1744 /* 1745 * Sync any current changes before 1746 * we go trundling through the block pointers. 1747 */ 1748 for (i = 0; i < TXG_SIZE; i++) { 1749 if (list_link_active(&dn->dn_dirty_link[i])) 1750 break; 1751 } 1752 if (i != TXG_SIZE) { 1753 dnode_rele(dn, FTAG); 1754 txg_wait_synced(dmu_objset_pool(os), 0); 1755 err = dnode_hold(os, object, FTAG, &dn); 1756 if (err) 1757 return (err); 1758 } 1759 1760 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 1761 dnode_rele(dn, FTAG); 1762 1763 return (err); 1764 } 1765 1766 void 1767 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 1768 { 1769 dnode_phys_t *dnp; 1770 1771 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1772 mutex_enter(&dn->dn_mtx); 1773 1774 dnp = dn->dn_phys; 1775 1776 doi->doi_data_block_size = dn->dn_datablksz; 1777 doi->doi_metadata_block_size = dn->dn_indblkshift ? 1778 1ULL << dn->dn_indblkshift : 0; 1779 doi->doi_type = dn->dn_type; 1780 doi->doi_bonus_type = dn->dn_bonustype; 1781 doi->doi_bonus_size = dn->dn_bonuslen; 1782 doi->doi_indirection = dn->dn_nlevels; 1783 doi->doi_checksum = dn->dn_checksum; 1784 doi->doi_compress = dn->dn_compress; 1785 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9; 1786 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 1787 doi->doi_fill_count = 0; 1788 for (int i = 0; i < dnp->dn_nblkptr; i++) 1789 doi->doi_fill_count += BP_GET_FILL(&dnp->dn_blkptr[i]); 1790 1791 mutex_exit(&dn->dn_mtx); 1792 rw_exit(&dn->dn_struct_rwlock); 1793 } 1794 1795 /* 1796 * Get information on a DMU object. 1797 * If doi is NULL, just indicates whether the object exists. 1798 */ 1799 int 1800 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 1801 { 1802 dnode_t *dn; 1803 int err = dnode_hold(os, object, FTAG, &dn); 1804 1805 if (err) 1806 return (err); 1807 1808 if (doi != NULL) 1809 dmu_object_info_from_dnode(dn, doi); 1810 1811 dnode_rele(dn, FTAG); 1812 return (0); 1813 } 1814 1815 /* 1816 * As above, but faster; can be used when you have a held dbuf in hand. 1817 */ 1818 void 1819 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi) 1820 { 1821 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 1822 1823 DB_DNODE_ENTER(db); 1824 dmu_object_info_from_dnode(DB_DNODE(db), doi); 1825 DB_DNODE_EXIT(db); 1826 } 1827 1828 /* 1829 * Faster still when you only care about the size. 1830 * This is specifically optimized for zfs_getattr(). 1831 */ 1832 void 1833 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize, 1834 u_longlong_t *nblk512) 1835 { 1836 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 1837 dnode_t *dn; 1838 1839 DB_DNODE_ENTER(db); 1840 dn = DB_DNODE(db); 1841 1842 *blksize = dn->dn_datablksz; 1843 /* add 1 for dnode space */ 1844 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 1845 SPA_MINBLOCKSHIFT) + 1; 1846 DB_DNODE_EXIT(db); 1847 } 1848 1849 void 1850 byteswap_uint64_array(void *vbuf, size_t size) 1851 { 1852 uint64_t *buf = vbuf; 1853 size_t count = size >> 3; 1854 int i; 1855 1856 ASSERT((size & 7) == 0); 1857 1858 for (i = 0; i < count; i++) 1859 buf[i] = BSWAP_64(buf[i]); 1860 } 1861 1862 void 1863 byteswap_uint32_array(void *vbuf, size_t size) 1864 { 1865 uint32_t *buf = vbuf; 1866 size_t count = size >> 2; 1867 int i; 1868 1869 ASSERT((size & 3) == 0); 1870 1871 for (i = 0; i < count; i++) 1872 buf[i] = BSWAP_32(buf[i]); 1873 } 1874 1875 void 1876 byteswap_uint16_array(void *vbuf, size_t size) 1877 { 1878 uint16_t *buf = vbuf; 1879 size_t count = size >> 1; 1880 int i; 1881 1882 ASSERT((size & 1) == 0); 1883 1884 for (i = 0; i < count; i++) 1885 buf[i] = BSWAP_16(buf[i]); 1886 } 1887 1888 /* ARGSUSED */ 1889 void 1890 byteswap_uint8_array(void *vbuf, size_t size) 1891 { 1892 } 1893 1894 void 1895 dmu_init(void) 1896 { 1897 zfs_dbgmsg_init(); 1898 sa_cache_init(); 1899 xuio_stat_init(); 1900 dmu_objset_init(); 1901 dnode_init(); 1902 dbuf_init(); 1903 zfetch_init(); 1904 l2arc_init(); 1905 arc_init(); 1906 } 1907 1908 void 1909 dmu_fini(void) 1910 { 1911 arc_fini(); /* arc depends on l2arc, so arc must go first */ 1912 l2arc_fini(); 1913 zfetch_fini(); 1914 dbuf_fini(); 1915 dnode_fini(); 1916 dmu_objset_fini(); 1917 xuio_stat_fini(); 1918 sa_cache_fini(); 1919 zfs_dbgmsg_fini(); 1920 } 1921