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) 2013 by Delphix. All rights reserved. 24 * Copyright (c) 2013 Martin Matuska. All rights reserved. 25 */ 26 27 #include <sys/dmu.h> 28 #include <sys/dmu_impl.h> 29 #include <sys/dmu_tx.h> 30 #include <sys/dbuf.h> 31 #include <sys/dnode.h> 32 #include <sys/zfs_context.h> 33 #include <sys/dmu_objset.h> 34 #include <sys/dmu_traverse.h> 35 #include <sys/dsl_dataset.h> 36 #include <sys/dsl_dir.h> 37 #include <sys/dsl_pool.h> 38 #include <sys/dsl_synctask.h> 39 #include <sys/dsl_prop.h> 40 #include <sys/dmu_zfetch.h> 41 #include <sys/zfs_ioctl.h> 42 #include <sys/zap.h> 43 #include <sys/zio_checksum.h> 44 #include <sys/zio_compress.h> 45 #include <sys/sa.h> 46 #include <sys/zfeature.h> 47 #ifdef _KERNEL 48 #include <sys/vmsystm.h> 49 #include <sys/zfs_znode.h> 50 #endif 51 52 /* 53 * Enable/disable nopwrite feature. 54 */ 55 int zfs_nopwrite_enabled = 1; 56 57 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { 58 { DMU_BSWAP_UINT8, TRUE, "unallocated" }, 59 { DMU_BSWAP_ZAP, TRUE, "object directory" }, 60 { DMU_BSWAP_UINT64, TRUE, "object array" }, 61 { DMU_BSWAP_UINT8, TRUE, "packed nvlist" }, 62 { DMU_BSWAP_UINT64, TRUE, "packed nvlist size" }, 63 { DMU_BSWAP_UINT64, TRUE, "bpobj" }, 64 { DMU_BSWAP_UINT64, TRUE, "bpobj header" }, 65 { DMU_BSWAP_UINT64, TRUE, "SPA space map header" }, 66 { DMU_BSWAP_UINT64, TRUE, "SPA space map" }, 67 { DMU_BSWAP_UINT64, TRUE, "ZIL intent log" }, 68 { DMU_BSWAP_DNODE, TRUE, "DMU dnode" }, 69 { DMU_BSWAP_OBJSET, TRUE, "DMU objset" }, 70 { DMU_BSWAP_UINT64, TRUE, "DSL directory" }, 71 { DMU_BSWAP_ZAP, TRUE, "DSL directory child map"}, 72 { DMU_BSWAP_ZAP, TRUE, "DSL dataset snap map" }, 73 { DMU_BSWAP_ZAP, TRUE, "DSL props" }, 74 { DMU_BSWAP_UINT64, TRUE, "DSL dataset" }, 75 { DMU_BSWAP_ZNODE, TRUE, "ZFS znode" }, 76 { DMU_BSWAP_OLDACL, TRUE, "ZFS V0 ACL" }, 77 { DMU_BSWAP_UINT8, FALSE, "ZFS plain file" }, 78 { DMU_BSWAP_ZAP, TRUE, "ZFS directory" }, 79 { DMU_BSWAP_ZAP, TRUE, "ZFS master node" }, 80 { DMU_BSWAP_ZAP, TRUE, "ZFS delete queue" }, 81 { DMU_BSWAP_UINT8, FALSE, "zvol object" }, 82 { DMU_BSWAP_ZAP, TRUE, "zvol prop" }, 83 { DMU_BSWAP_UINT8, FALSE, "other uint8[]" }, 84 { DMU_BSWAP_UINT64, FALSE, "other uint64[]" }, 85 { DMU_BSWAP_ZAP, TRUE, "other ZAP" }, 86 { DMU_BSWAP_ZAP, TRUE, "persistent error log" }, 87 { DMU_BSWAP_UINT8, TRUE, "SPA history" }, 88 { DMU_BSWAP_UINT64, TRUE, "SPA history offsets" }, 89 { DMU_BSWAP_ZAP, TRUE, "Pool properties" }, 90 { DMU_BSWAP_ZAP, TRUE, "DSL permissions" }, 91 { DMU_BSWAP_ACL, TRUE, "ZFS ACL" }, 92 { DMU_BSWAP_UINT8, TRUE, "ZFS SYSACL" }, 93 { DMU_BSWAP_UINT8, TRUE, "FUID table" }, 94 { DMU_BSWAP_UINT64, TRUE, "FUID table size" }, 95 { DMU_BSWAP_ZAP, TRUE, "DSL dataset next clones"}, 96 { DMU_BSWAP_ZAP, TRUE, "scan work queue" }, 97 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group used" }, 98 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group quota" }, 99 { DMU_BSWAP_ZAP, TRUE, "snapshot refcount tags"}, 100 { DMU_BSWAP_ZAP, TRUE, "DDT ZAP algorithm" }, 101 { DMU_BSWAP_ZAP, TRUE, "DDT statistics" }, 102 { DMU_BSWAP_UINT8, TRUE, "System attributes" }, 103 { DMU_BSWAP_ZAP, TRUE, "SA master node" }, 104 { DMU_BSWAP_ZAP, TRUE, "SA attr registration" }, 105 { DMU_BSWAP_ZAP, TRUE, "SA attr layouts" }, 106 { DMU_BSWAP_ZAP, TRUE, "scan translations" }, 107 { DMU_BSWAP_UINT8, FALSE, "deduplicated block" }, 108 { DMU_BSWAP_ZAP, TRUE, "DSL deadlist map" }, 109 { DMU_BSWAP_UINT64, TRUE, "DSL deadlist map hdr" }, 110 { DMU_BSWAP_ZAP, TRUE, "DSL dir clones" }, 111 { DMU_BSWAP_UINT64, TRUE, "bpobj subobj" } 112 }; 113 114 const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = { 115 { byteswap_uint8_array, "uint8" }, 116 { byteswap_uint16_array, "uint16" }, 117 { byteswap_uint32_array, "uint32" }, 118 { byteswap_uint64_array, "uint64" }, 119 { zap_byteswap, "zap" }, 120 { dnode_buf_byteswap, "dnode" }, 121 { dmu_objset_byteswap, "objset" }, 122 { zfs_znode_byteswap, "znode" }, 123 { zfs_oldacl_byteswap, "oldacl" }, 124 { zfs_acl_byteswap, "acl" } 125 }; 126 127 int 128 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, 129 void *tag, dmu_buf_t **dbp, int flags) 130 { 131 dnode_t *dn; 132 uint64_t blkid; 133 dmu_buf_impl_t *db; 134 int err; 135 int db_flags = DB_RF_CANFAIL; 136 137 if (flags & DMU_READ_NO_PREFETCH) 138 db_flags |= DB_RF_NOPREFETCH; 139 140 err = dnode_hold(os, object, FTAG, &dn); 141 if (err) 142 return (err); 143 blkid = dbuf_whichblock(dn, offset); 144 rw_enter(&dn->dn_struct_rwlock, RW_READER); 145 db = dbuf_hold(dn, blkid, tag); 146 rw_exit(&dn->dn_struct_rwlock); 147 if (db == NULL) { 148 err = SET_ERROR(EIO); 149 } else { 150 err = dbuf_read(db, NULL, db_flags); 151 if (err) { 152 dbuf_rele(db, tag); 153 db = NULL; 154 } 155 } 156 157 dnode_rele(dn, FTAG); 158 *dbp = &db->db; /* NULL db plus first field offset is NULL */ 159 return (err); 160 } 161 162 int 163 dmu_bonus_max(void) 164 { 165 return (DN_MAX_BONUSLEN); 166 } 167 168 int 169 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx) 170 { 171 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 172 dnode_t *dn; 173 int error; 174 175 DB_DNODE_ENTER(db); 176 dn = DB_DNODE(db); 177 178 if (dn->dn_bonus != db) { 179 error = SET_ERROR(EINVAL); 180 } else if (newsize < 0 || newsize > db_fake->db_size) { 181 error = SET_ERROR(EINVAL); 182 } else { 183 dnode_setbonuslen(dn, newsize, tx); 184 error = 0; 185 } 186 187 DB_DNODE_EXIT(db); 188 return (error); 189 } 190 191 int 192 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx) 193 { 194 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 195 dnode_t *dn; 196 int error; 197 198 DB_DNODE_ENTER(db); 199 dn = DB_DNODE(db); 200 201 if (!DMU_OT_IS_VALID(type)) { 202 error = SET_ERROR(EINVAL); 203 } else if (dn->dn_bonus != db) { 204 error = SET_ERROR(EINVAL); 205 } else { 206 dnode_setbonus_type(dn, type, tx); 207 error = 0; 208 } 209 210 DB_DNODE_EXIT(db); 211 return (error); 212 } 213 214 dmu_object_type_t 215 dmu_get_bonustype(dmu_buf_t *db_fake) 216 { 217 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 218 dnode_t *dn; 219 dmu_object_type_t type; 220 221 DB_DNODE_ENTER(db); 222 dn = DB_DNODE(db); 223 type = dn->dn_bonustype; 224 DB_DNODE_EXIT(db); 225 226 return (type); 227 } 228 229 int 230 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx) 231 { 232 dnode_t *dn; 233 int error; 234 235 error = dnode_hold(os, object, FTAG, &dn); 236 dbuf_rm_spill(dn, tx); 237 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 238 dnode_rm_spill(dn, tx); 239 rw_exit(&dn->dn_struct_rwlock); 240 dnode_rele(dn, FTAG); 241 return (error); 242 } 243 244 /* 245 * returns ENOENT, EIO, or 0. 246 */ 247 int 248 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp) 249 { 250 dnode_t *dn; 251 dmu_buf_impl_t *db; 252 int error; 253 254 error = dnode_hold(os, object, FTAG, &dn); 255 if (error) 256 return (error); 257 258 rw_enter(&dn->dn_struct_rwlock, RW_READER); 259 if (dn->dn_bonus == NULL) { 260 rw_exit(&dn->dn_struct_rwlock); 261 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 262 if (dn->dn_bonus == NULL) 263 dbuf_create_bonus(dn); 264 } 265 db = dn->dn_bonus; 266 267 /* as long as the bonus buf is held, the dnode will be held */ 268 if (refcount_add(&db->db_holds, tag) == 1) { 269 VERIFY(dnode_add_ref(dn, db)); 270 (void) atomic_inc_32_nv(&dn->dn_dbufs_count); 271 } 272 273 /* 274 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's 275 * hold and incrementing the dbuf count to ensure that dnode_move() sees 276 * a dnode hold for every dbuf. 277 */ 278 rw_exit(&dn->dn_struct_rwlock); 279 280 dnode_rele(dn, FTAG); 281 282 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH)); 283 284 *dbp = &db->db; 285 return (0); 286 } 287 288 /* 289 * returns ENOENT, EIO, or 0. 290 * 291 * This interface will allocate a blank spill dbuf when a spill blk 292 * doesn't already exist on the dnode. 293 * 294 * if you only want to find an already existing spill db, then 295 * dmu_spill_hold_existing() should be used. 296 */ 297 int 298 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp) 299 { 300 dmu_buf_impl_t *db = NULL; 301 int err; 302 303 if ((flags & DB_RF_HAVESTRUCT) == 0) 304 rw_enter(&dn->dn_struct_rwlock, RW_READER); 305 306 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag); 307 308 if ((flags & DB_RF_HAVESTRUCT) == 0) 309 rw_exit(&dn->dn_struct_rwlock); 310 311 ASSERT(db != NULL); 312 err = dbuf_read(db, NULL, flags); 313 if (err == 0) 314 *dbp = &db->db; 315 else 316 dbuf_rele(db, tag); 317 return (err); 318 } 319 320 int 321 dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp) 322 { 323 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 324 dnode_t *dn; 325 int err; 326 327 DB_DNODE_ENTER(db); 328 dn = DB_DNODE(db); 329 330 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) { 331 err = SET_ERROR(EINVAL); 332 } else { 333 rw_enter(&dn->dn_struct_rwlock, RW_READER); 334 335 if (!dn->dn_have_spill) { 336 err = SET_ERROR(ENOENT); 337 } else { 338 err = dmu_spill_hold_by_dnode(dn, 339 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp); 340 } 341 342 rw_exit(&dn->dn_struct_rwlock); 343 } 344 345 DB_DNODE_EXIT(db); 346 return (err); 347 } 348 349 int 350 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp) 351 { 352 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; 353 dnode_t *dn; 354 int err; 355 356 DB_DNODE_ENTER(db); 357 dn = DB_DNODE(db); 358 err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp); 359 DB_DNODE_EXIT(db); 360 361 return (err); 362 } 363 364 /* 365 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces 366 * to take a held dnode rather than <os, object> -- the lookup is wasteful, 367 * and can induce severe lock contention when writing to several files 368 * whose dnodes are in the same block. 369 */ 370 static int 371 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, 372 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags) 373 { 374 dsl_pool_t *dp = NULL; 375 dmu_buf_t **dbp; 376 uint64_t blkid, nblks, i; 377 uint32_t dbuf_flags; 378 int err; 379 zio_t *zio; 380 hrtime_t start; 381 382 ASSERT(length <= DMU_MAX_ACCESS); 383 384 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT; 385 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz) 386 dbuf_flags |= DB_RF_NOPREFETCH; 387 388 rw_enter(&dn->dn_struct_rwlock, RW_READER); 389 if (dn->dn_datablkshift) { 390 int blkshift = dn->dn_datablkshift; 391 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) - 392 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift; 393 } else { 394 if (offset + length > dn->dn_datablksz) { 395 zfs_panic_recover("zfs: accessing past end of object " 396 "%llx/%llx (size=%u access=%llu+%llu)", 397 (longlong_t)dn->dn_objset-> 398 os_dsl_dataset->ds_object, 399 (longlong_t)dn->dn_object, dn->dn_datablksz, 400 (longlong_t)offset, (longlong_t)length); 401 rw_exit(&dn->dn_struct_rwlock); 402 return (SET_ERROR(EIO)); 403 } 404 nblks = 1; 405 } 406 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); 407 408 if (dn->dn_objset->os_dsl_dataset) 409 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool; 410 start = gethrtime(); 411 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); 412 blkid = dbuf_whichblock(dn, offset); 413 for (i = 0; i < nblks; i++) { 414 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag); 415 if (db == NULL) { 416 rw_exit(&dn->dn_struct_rwlock); 417 dmu_buf_rele_array(dbp, nblks, tag); 418 zio_nowait(zio); 419 return (SET_ERROR(EIO)); 420 } 421 /* initiate async i/o */ 422 if (read) { 423 (void) dbuf_read(db, zio, dbuf_flags); 424 } 425 dbp[i] = &db->db; 426 } 427 rw_exit(&dn->dn_struct_rwlock); 428 429 /* wait for async i/o */ 430 err = zio_wait(zio); 431 /* track read overhead when we are in sync context */ 432 if (dp && dsl_pool_sync_context(dp)) 433 dp->dp_read_overhead += gethrtime() - start; 434 if (err) { 435 dmu_buf_rele_array(dbp, nblks, tag); 436 return (err); 437 } 438 439 /* wait for other io to complete */ 440 if (read) { 441 for (i = 0; i < nblks; i++) { 442 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; 443 mutex_enter(&db->db_mtx); 444 while (db->db_state == DB_READ || 445 db->db_state == DB_FILL) 446 cv_wait(&db->db_changed, &db->db_mtx); 447 if (db->db_state == DB_UNCACHED) 448 err = SET_ERROR(EIO); 449 mutex_exit(&db->db_mtx); 450 if (err) { 451 dmu_buf_rele_array(dbp, nblks, tag); 452 return (err); 453 } 454 } 455 } 456 457 *numbufsp = nblks; 458 *dbpp = dbp; 459 return (0); 460 } 461 462 static int 463 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, 464 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 465 { 466 dnode_t *dn; 467 int err; 468 469 err = dnode_hold(os, object, FTAG, &dn); 470 if (err) 471 return (err); 472 473 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 474 numbufsp, dbpp, DMU_READ_PREFETCH); 475 476 dnode_rele(dn, FTAG); 477 478 return (err); 479 } 480 481 int 482 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset, 483 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp) 484 { 485 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 486 dnode_t *dn; 487 int err; 488 489 DB_DNODE_ENTER(db); 490 dn = DB_DNODE(db); 491 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, 492 numbufsp, dbpp, DMU_READ_PREFETCH); 493 DB_DNODE_EXIT(db); 494 495 return (err); 496 } 497 498 void 499 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) 500 { 501 int i; 502 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; 503 504 if (numbufs == 0) 505 return; 506 507 for (i = 0; i < numbufs; i++) { 508 if (dbp[i]) 509 dbuf_rele(dbp[i], tag); 510 } 511 512 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); 513 } 514 515 void 516 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) 517 { 518 dnode_t *dn; 519 uint64_t blkid; 520 int nblks, i, err; 521 522 if (zfs_prefetch_disable) 523 return; 524 525 if (len == 0) { /* they're interested in the bonus buffer */ 526 dn = DMU_META_DNODE(os); 527 528 if (object == 0 || object >= DN_MAX_OBJECT) 529 return; 530 531 rw_enter(&dn->dn_struct_rwlock, RW_READER); 532 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); 533 dbuf_prefetch(dn, blkid); 534 rw_exit(&dn->dn_struct_rwlock); 535 return; 536 } 537 538 /* 539 * XXX - Note, if the dnode for the requested object is not 540 * already cached, we will do a *synchronous* read in the 541 * dnode_hold() call. The same is true for any indirects. 542 */ 543 err = dnode_hold(os, object, FTAG, &dn); 544 if (err != 0) 545 return; 546 547 rw_enter(&dn->dn_struct_rwlock, RW_READER); 548 if (dn->dn_datablkshift) { 549 int blkshift = dn->dn_datablkshift; 550 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) - 551 P2ALIGN(offset, 1<<blkshift)) >> blkshift; 552 } else { 553 nblks = (offset < dn->dn_datablksz); 554 } 555 556 if (nblks != 0) { 557 blkid = dbuf_whichblock(dn, offset); 558 for (i = 0; i < nblks; i++) 559 dbuf_prefetch(dn, blkid+i); 560 } 561 562 rw_exit(&dn->dn_struct_rwlock); 563 564 dnode_rele(dn, FTAG); 565 } 566 567 /* 568 * Get the next "chunk" of file data to free. We traverse the file from 569 * the end so that the file gets shorter over time (if we crashes in the 570 * middle, this will leave us in a better state). We find allocated file 571 * data by simply searching the allocated level 1 indirects. 572 */ 573 static int 574 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit) 575 { 576 uint64_t len = *start - limit; 577 uint64_t blkcnt = 0; 578 uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1)); 579 uint64_t iblkrange = 580 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); 581 582 ASSERT(limit <= *start); 583 584 if (len <= iblkrange * maxblks) { 585 *start = limit; 586 return (0); 587 } 588 ASSERT(ISP2(iblkrange)); 589 590 while (*start > limit && blkcnt < maxblks) { 591 int err; 592 593 /* find next allocated L1 indirect */ 594 err = dnode_next_offset(dn, 595 DNODE_FIND_BACKWARDS, start, 2, 1, 0); 596 597 /* if there are no more, then we are done */ 598 if (err == ESRCH) { 599 *start = limit; 600 return (0); 601 } else if (err) { 602 return (err); 603 } 604 blkcnt += 1; 605 606 /* reset offset to end of "next" block back */ 607 *start = P2ALIGN(*start, iblkrange); 608 if (*start <= limit) 609 *start = limit; 610 else 611 *start -= 1; 612 } 613 return (0); 614 } 615 616 static int 617 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, 618 uint64_t length, boolean_t free_dnode) 619 { 620 dmu_tx_t *tx; 621 uint64_t object_size, start, end, len; 622 boolean_t trunc = (length == DMU_OBJECT_END); 623 int align, err; 624 625 align = 1 << dn->dn_datablkshift; 626 ASSERT(align > 0); 627 object_size = align == 1 ? dn->dn_datablksz : 628 (dn->dn_maxblkid + 1) << dn->dn_datablkshift; 629 630 end = offset + length; 631 if (trunc || end > object_size) 632 end = object_size; 633 if (end <= offset) 634 return (0); 635 length = end - offset; 636 637 while (length) { 638 start = end; 639 /* assert(offset <= start) */ 640 err = get_next_chunk(dn, &start, offset); 641 if (err) 642 return (err); 643 len = trunc ? DMU_OBJECT_END : end - start; 644 645 tx = dmu_tx_create(os); 646 dmu_tx_hold_free(tx, dn->dn_object, start, len); 647 err = dmu_tx_assign(tx, TXG_WAIT); 648 if (err) { 649 dmu_tx_abort(tx); 650 return (err); 651 } 652 653 dnode_free_range(dn, start, trunc ? -1 : len, tx); 654 655 if (start == 0 && free_dnode) { 656 ASSERT(trunc); 657 dnode_free(dn, tx); 658 } 659 660 length -= end - start; 661 662 dmu_tx_commit(tx); 663 end = start; 664 } 665 return (0); 666 } 667 668 int 669 dmu_free_long_range(objset_t *os, uint64_t object, 670 uint64_t offset, uint64_t length) 671 { 672 dnode_t *dn; 673 int err; 674 675 err = dnode_hold(os, object, FTAG, &dn); 676 if (err != 0) 677 return (err); 678 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE); 679 dnode_rele(dn, FTAG); 680 return (err); 681 } 682 683 int 684 dmu_free_object(objset_t *os, uint64_t object) 685 { 686 dnode_t *dn; 687 dmu_tx_t *tx; 688 int err; 689 690 err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 691 FTAG, &dn); 692 if (err != 0) 693 return (err); 694 if (dn->dn_nlevels == 1) { 695 tx = dmu_tx_create(os); 696 dmu_tx_hold_bonus(tx, object); 697 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END); 698 err = dmu_tx_assign(tx, TXG_WAIT); 699 if (err == 0) { 700 dnode_free_range(dn, 0, DMU_OBJECT_END, tx); 701 dnode_free(dn, tx); 702 dmu_tx_commit(tx); 703 } else { 704 dmu_tx_abort(tx); 705 } 706 } else { 707 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE); 708 } 709 dnode_rele(dn, FTAG); 710 return (err); 711 } 712 713 int 714 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, 715 uint64_t size, dmu_tx_t *tx) 716 { 717 dnode_t *dn; 718 int err = dnode_hold(os, object, FTAG, &dn); 719 if (err) 720 return (err); 721 ASSERT(offset < UINT64_MAX); 722 ASSERT(size == -1ULL || size <= UINT64_MAX - offset); 723 dnode_free_range(dn, offset, size, tx); 724 dnode_rele(dn, FTAG); 725 return (0); 726 } 727 728 int 729 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 730 void *buf, uint32_t flags) 731 { 732 dnode_t *dn; 733 dmu_buf_t **dbp; 734 int numbufs, err; 735 736 err = dnode_hold(os, object, FTAG, &dn); 737 if (err) 738 return (err); 739 740 /* 741 * Deal with odd block sizes, where there can't be data past the first 742 * block. If we ever do the tail block optimization, we will need to 743 * handle that here as well. 744 */ 745 if (dn->dn_maxblkid == 0) { 746 int newsz = offset > dn->dn_datablksz ? 0 : 747 MIN(size, dn->dn_datablksz - offset); 748 bzero((char *)buf + newsz, size - newsz); 749 size = newsz; 750 } 751 752 while (size > 0) { 753 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); 754 int i; 755 756 /* 757 * NB: we could do this block-at-a-time, but it's nice 758 * to be reading in parallel. 759 */ 760 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, 761 TRUE, FTAG, &numbufs, &dbp, flags); 762 if (err) 763 break; 764 765 for (i = 0; i < numbufs; i++) { 766 int tocpy; 767 int bufoff; 768 dmu_buf_t *db = dbp[i]; 769 770 ASSERT(size > 0); 771 772 bufoff = offset - db->db_offset; 773 tocpy = (int)MIN(db->db_size - bufoff, size); 774 775 bcopy((char *)db->db_data + bufoff, buf, tocpy); 776 777 offset += tocpy; 778 size -= tocpy; 779 buf = (char *)buf + tocpy; 780 } 781 dmu_buf_rele_array(dbp, numbufs, FTAG); 782 } 783 dnode_rele(dn, FTAG); 784 return (err); 785 } 786 787 void 788 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 789 const void *buf, dmu_tx_t *tx) 790 { 791 dmu_buf_t **dbp; 792 int numbufs, i; 793 794 if (size == 0) 795 return; 796 797 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 798 FALSE, FTAG, &numbufs, &dbp)); 799 800 for (i = 0; i < numbufs; i++) { 801 int tocpy; 802 int bufoff; 803 dmu_buf_t *db = dbp[i]; 804 805 ASSERT(size > 0); 806 807 bufoff = offset - db->db_offset; 808 tocpy = (int)MIN(db->db_size - bufoff, size); 809 810 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 811 812 if (tocpy == db->db_size) 813 dmu_buf_will_fill(db, tx); 814 else 815 dmu_buf_will_dirty(db, tx); 816 817 bcopy(buf, (char *)db->db_data + bufoff, tocpy); 818 819 if (tocpy == db->db_size) 820 dmu_buf_fill_done(db, tx); 821 822 offset += tocpy; 823 size -= tocpy; 824 buf = (char *)buf + tocpy; 825 } 826 dmu_buf_rele_array(dbp, numbufs, FTAG); 827 } 828 829 void 830 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 831 dmu_tx_t *tx) 832 { 833 dmu_buf_t **dbp; 834 int numbufs, i; 835 836 if (size == 0) 837 return; 838 839 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, 840 FALSE, FTAG, &numbufs, &dbp)); 841 842 for (i = 0; i < numbufs; i++) { 843 dmu_buf_t *db = dbp[i]; 844 845 dmu_buf_will_not_fill(db, tx); 846 } 847 dmu_buf_rele_array(dbp, numbufs, FTAG); 848 } 849 850 /* 851 * DMU support for xuio 852 */ 853 kstat_t *xuio_ksp = NULL; 854 855 int 856 dmu_xuio_init(xuio_t *xuio, int nblk) 857 { 858 dmu_xuio_t *priv; 859 uio_t *uio = &xuio->xu_uio; 860 861 uio->uio_iovcnt = nblk; 862 uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_SLEEP); 863 864 priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP); 865 priv->cnt = nblk; 866 priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP); 867 priv->iovp = uio->uio_iov; 868 XUIO_XUZC_PRIV(xuio) = priv; 869 870 if (XUIO_XUZC_RW(xuio) == UIO_READ) 871 XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk); 872 else 873 XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk); 874 875 return (0); 876 } 877 878 void 879 dmu_xuio_fini(xuio_t *xuio) 880 { 881 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 882 int nblk = priv->cnt; 883 884 kmem_free(priv->iovp, nblk * sizeof (iovec_t)); 885 kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *)); 886 kmem_free(priv, sizeof (dmu_xuio_t)); 887 888 if (XUIO_XUZC_RW(xuio) == UIO_READ) 889 XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk); 890 else 891 XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk); 892 } 893 894 /* 895 * Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf } 896 * and increase priv->next by 1. 897 */ 898 int 899 dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n) 900 { 901 struct iovec *iov; 902 uio_t *uio = &xuio->xu_uio; 903 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 904 int i = priv->next++; 905 906 ASSERT(i < priv->cnt); 907 ASSERT(off + n <= arc_buf_size(abuf)); 908 iov = uio->uio_iov + i; 909 iov->iov_base = (char *)abuf->b_data + off; 910 iov->iov_len = n; 911 priv->bufs[i] = abuf; 912 return (0); 913 } 914 915 int 916 dmu_xuio_cnt(xuio_t *xuio) 917 { 918 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 919 return (priv->cnt); 920 } 921 922 arc_buf_t * 923 dmu_xuio_arcbuf(xuio_t *xuio, int i) 924 { 925 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 926 927 ASSERT(i < priv->cnt); 928 return (priv->bufs[i]); 929 } 930 931 void 932 dmu_xuio_clear(xuio_t *xuio, int i) 933 { 934 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio); 935 936 ASSERT(i < priv->cnt); 937 priv->bufs[i] = NULL; 938 } 939 940 static void 941 xuio_stat_init(void) 942 { 943 xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc", 944 KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t), 945 KSTAT_FLAG_VIRTUAL); 946 if (xuio_ksp != NULL) { 947 xuio_ksp->ks_data = &xuio_stats; 948 kstat_install(xuio_ksp); 949 } 950 } 951 952 static void 953 xuio_stat_fini(void) 954 { 955 if (xuio_ksp != NULL) { 956 kstat_delete(xuio_ksp); 957 xuio_ksp = NULL; 958 } 959 } 960 961 void 962 xuio_stat_wbuf_copied() 963 { 964 XUIOSTAT_BUMP(xuiostat_wbuf_copied); 965 } 966 967 void 968 xuio_stat_wbuf_nocopy() 969 { 970 XUIOSTAT_BUMP(xuiostat_wbuf_nocopy); 971 } 972 973 #ifdef _KERNEL 974 int 975 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size) 976 { 977 dmu_buf_t **dbp; 978 int numbufs, i, err; 979 xuio_t *xuio = NULL; 980 981 /* 982 * NB: we could do this block-at-a-time, but it's nice 983 * to be reading in parallel. 984 */ 985 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG, 986 &numbufs, &dbp); 987 if (err) 988 return (err); 989 990 if (uio->uio_extflg == UIO_XUIO) 991 xuio = (xuio_t *)uio; 992 993 for (i = 0; i < numbufs; i++) { 994 int tocpy; 995 int bufoff; 996 dmu_buf_t *db = dbp[i]; 997 998 ASSERT(size > 0); 999 1000 bufoff = uio->uio_loffset - db->db_offset; 1001 tocpy = (int)MIN(db->db_size - bufoff, size); 1002 1003 if (xuio) { 1004 dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db; 1005 arc_buf_t *dbuf_abuf = dbi->db_buf; 1006 arc_buf_t *abuf = dbuf_loan_arcbuf(dbi); 1007 err = dmu_xuio_add(xuio, abuf, bufoff, tocpy); 1008 if (!err) { 1009 uio->uio_resid -= tocpy; 1010 uio->uio_loffset += tocpy; 1011 } 1012 1013 if (abuf == dbuf_abuf) 1014 XUIOSTAT_BUMP(xuiostat_rbuf_nocopy); 1015 else 1016 XUIOSTAT_BUMP(xuiostat_rbuf_copied); 1017 } else { 1018 err = uiomove((char *)db->db_data + bufoff, tocpy, 1019 UIO_READ, uio); 1020 } 1021 if (err) 1022 break; 1023 1024 size -= tocpy; 1025 } 1026 dmu_buf_rele_array(dbp, numbufs, FTAG); 1027 1028 return (err); 1029 } 1030 1031 static int 1032 dmu_write_uio_dnode(dnode_t *dn, uio_t *uio, uint64_t size, dmu_tx_t *tx) 1033 { 1034 dmu_buf_t **dbp; 1035 int numbufs; 1036 int err = 0; 1037 int i; 1038 1039 err = dmu_buf_hold_array_by_dnode(dn, uio->uio_loffset, size, 1040 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH); 1041 if (err) 1042 return (err); 1043 1044 for (i = 0; i < numbufs; i++) { 1045 int tocpy; 1046 int bufoff; 1047 dmu_buf_t *db = dbp[i]; 1048 1049 ASSERT(size > 0); 1050 1051 bufoff = uio->uio_loffset - db->db_offset; 1052 tocpy = (int)MIN(db->db_size - bufoff, size); 1053 1054 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1055 1056 if (tocpy == db->db_size) 1057 dmu_buf_will_fill(db, tx); 1058 else 1059 dmu_buf_will_dirty(db, tx); 1060 1061 /* 1062 * XXX uiomove could block forever (eg. nfs-backed 1063 * pages). There needs to be a uiolockdown() function 1064 * to lock the pages in memory, so that uiomove won't 1065 * block. 1066 */ 1067 err = uiomove((char *)db->db_data + bufoff, tocpy, 1068 UIO_WRITE, uio); 1069 1070 if (tocpy == db->db_size) 1071 dmu_buf_fill_done(db, tx); 1072 1073 if (err) 1074 break; 1075 1076 size -= tocpy; 1077 } 1078 1079 dmu_buf_rele_array(dbp, numbufs, FTAG); 1080 return (err); 1081 } 1082 1083 int 1084 dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size, 1085 dmu_tx_t *tx) 1086 { 1087 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; 1088 dnode_t *dn; 1089 int err; 1090 1091 if (size == 0) 1092 return (0); 1093 1094 DB_DNODE_ENTER(db); 1095 dn = DB_DNODE(db); 1096 err = dmu_write_uio_dnode(dn, uio, size, tx); 1097 DB_DNODE_EXIT(db); 1098 1099 return (err); 1100 } 1101 1102 int 1103 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size, 1104 dmu_tx_t *tx) 1105 { 1106 dnode_t *dn; 1107 int err; 1108 1109 if (size == 0) 1110 return (0); 1111 1112 err = dnode_hold(os, object, FTAG, &dn); 1113 if (err) 1114 return (err); 1115 1116 err = dmu_write_uio_dnode(dn, uio, size, tx); 1117 1118 dnode_rele(dn, FTAG); 1119 1120 return (err); 1121 } 1122 1123 int 1124 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, 1125 page_t *pp, dmu_tx_t *tx) 1126 { 1127 dmu_buf_t **dbp; 1128 int numbufs, i; 1129 int err; 1130 1131 if (size == 0) 1132 return (0); 1133 1134 err = dmu_buf_hold_array(os, object, offset, size, 1135 FALSE, FTAG, &numbufs, &dbp); 1136 if (err) 1137 return (err); 1138 1139 for (i = 0; i < numbufs; i++) { 1140 int tocpy, copied, thiscpy; 1141 int bufoff; 1142 dmu_buf_t *db = dbp[i]; 1143 caddr_t va; 1144 1145 ASSERT(size > 0); 1146 ASSERT3U(db->db_size, >=, PAGESIZE); 1147 1148 bufoff = offset - db->db_offset; 1149 tocpy = (int)MIN(db->db_size - bufoff, size); 1150 1151 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); 1152 1153 if (tocpy == db->db_size) 1154 dmu_buf_will_fill(db, tx); 1155 else 1156 dmu_buf_will_dirty(db, tx); 1157 1158 for (copied = 0; copied < tocpy; copied += PAGESIZE) { 1159 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff); 1160 thiscpy = MIN(PAGESIZE, tocpy - copied); 1161 va = zfs_map_page(pp, S_READ); 1162 bcopy(va, (char *)db->db_data + bufoff, thiscpy); 1163 zfs_unmap_page(pp, va); 1164 pp = pp->p_next; 1165 bufoff += PAGESIZE; 1166 } 1167 1168 if (tocpy == db->db_size) 1169 dmu_buf_fill_done(db, tx); 1170 1171 offset += tocpy; 1172 size -= tocpy; 1173 } 1174 dmu_buf_rele_array(dbp, numbufs, FTAG); 1175 return (err); 1176 } 1177 #endif 1178 1179 /* 1180 * Allocate a loaned anonymous arc buffer. 1181 */ 1182 arc_buf_t * 1183 dmu_request_arcbuf(dmu_buf_t *handle, int size) 1184 { 1185 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle; 1186 spa_t *spa; 1187 1188 DB_GET_SPA(&spa, db); 1189 return (arc_loan_buf(spa, size)); 1190 } 1191 1192 /* 1193 * Free a loaned arc buffer. 1194 */ 1195 void 1196 dmu_return_arcbuf(arc_buf_t *buf) 1197 { 1198 arc_return_buf(buf, FTAG); 1199 VERIFY(arc_buf_remove_ref(buf, FTAG)); 1200 } 1201 1202 /* 1203 * When possible directly assign passed loaned arc buffer to a dbuf. 1204 * If this is not possible copy the contents of passed arc buf via 1205 * dmu_write(). 1206 */ 1207 void 1208 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, 1209 dmu_tx_t *tx) 1210 { 1211 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle; 1212 dnode_t *dn; 1213 dmu_buf_impl_t *db; 1214 uint32_t blksz = (uint32_t)arc_buf_size(buf); 1215 uint64_t blkid; 1216 1217 DB_DNODE_ENTER(dbuf); 1218 dn = DB_DNODE(dbuf); 1219 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1220 blkid = dbuf_whichblock(dn, offset); 1221 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL); 1222 rw_exit(&dn->dn_struct_rwlock); 1223 DB_DNODE_EXIT(dbuf); 1224 1225 if (offset == db->db.db_offset && blksz == db->db.db_size) { 1226 dbuf_assign_arcbuf(db, buf, tx); 1227 dbuf_rele(db, FTAG); 1228 } else { 1229 objset_t *os; 1230 uint64_t object; 1231 1232 DB_DNODE_ENTER(dbuf); 1233 dn = DB_DNODE(dbuf); 1234 os = dn->dn_objset; 1235 object = dn->dn_object; 1236 DB_DNODE_EXIT(dbuf); 1237 1238 dbuf_rele(db, FTAG); 1239 dmu_write(os, object, offset, blksz, buf->b_data, tx); 1240 dmu_return_arcbuf(buf); 1241 XUIOSTAT_BUMP(xuiostat_wbuf_copied); 1242 } 1243 } 1244 1245 typedef struct { 1246 dbuf_dirty_record_t *dsa_dr; 1247 dmu_sync_cb_t *dsa_done; 1248 zgd_t *dsa_zgd; 1249 dmu_tx_t *dsa_tx; 1250 } dmu_sync_arg_t; 1251 1252 /* ARGSUSED */ 1253 static void 1254 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) 1255 { 1256 dmu_sync_arg_t *dsa = varg; 1257 dmu_buf_t *db = dsa->dsa_zgd->zgd_db; 1258 blkptr_t *bp = zio->io_bp; 1259 1260 if (zio->io_error == 0) { 1261 if (BP_IS_HOLE(bp)) { 1262 /* 1263 * A block of zeros may compress to a hole, but the 1264 * block size still needs to be known for replay. 1265 */ 1266 BP_SET_LSIZE(bp, db->db_size); 1267 } else { 1268 ASSERT(BP_GET_LEVEL(bp) == 0); 1269 bp->blk_fill = 1; 1270 } 1271 } 1272 } 1273 1274 static void 1275 dmu_sync_late_arrival_ready(zio_t *zio) 1276 { 1277 dmu_sync_ready(zio, NULL, zio->io_private); 1278 } 1279 1280 /* ARGSUSED */ 1281 static void 1282 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) 1283 { 1284 dmu_sync_arg_t *dsa = varg; 1285 dbuf_dirty_record_t *dr = dsa->dsa_dr; 1286 dmu_buf_impl_t *db = dr->dr_dbuf; 1287 1288 mutex_enter(&db->db_mtx); 1289 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); 1290 if (zio->io_error == 0) { 1291 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE); 1292 if (dr->dt.dl.dr_nopwrite) { 1293 blkptr_t *bp = zio->io_bp; 1294 blkptr_t *bp_orig = &zio->io_bp_orig; 1295 uint8_t chksum = BP_GET_CHECKSUM(bp_orig); 1296 1297 ASSERT(BP_EQUAL(bp, bp_orig)); 1298 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF); 1299 ASSERT(zio_checksum_table[chksum].ci_dedup); 1300 } 1301 dr->dt.dl.dr_overridden_by = *zio->io_bp; 1302 dr->dt.dl.dr_override_state = DR_OVERRIDDEN; 1303 dr->dt.dl.dr_copies = zio->io_prop.zp_copies; 1304 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by)) 1305 BP_ZERO(&dr->dt.dl.dr_overridden_by); 1306 } else { 1307 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; 1308 } 1309 cv_broadcast(&db->db_changed); 1310 mutex_exit(&db->db_mtx); 1311 1312 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1313 1314 kmem_free(dsa, sizeof (*dsa)); 1315 } 1316 1317 static void 1318 dmu_sync_late_arrival_done(zio_t *zio) 1319 { 1320 blkptr_t *bp = zio->io_bp; 1321 dmu_sync_arg_t *dsa = zio->io_private; 1322 blkptr_t *bp_orig = &zio->io_bp_orig; 1323 1324 if (zio->io_error == 0 && !BP_IS_HOLE(bp)) { 1325 /* 1326 * If we didn't allocate a new block (i.e. ZIO_FLAG_NOPWRITE) 1327 * then there is nothing to do here. Otherwise, free the 1328 * newly allocated block in this txg. 1329 */ 1330 if (zio->io_flags & ZIO_FLAG_NOPWRITE) { 1331 ASSERT(BP_EQUAL(bp, bp_orig)); 1332 } else { 1333 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig)); 1334 ASSERT(zio->io_bp->blk_birth == zio->io_txg); 1335 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa)); 1336 zio_free(zio->io_spa, zio->io_txg, zio->io_bp); 1337 } 1338 } 1339 1340 dmu_tx_commit(dsa->dsa_tx); 1341 1342 dsa->dsa_done(dsa->dsa_zgd, zio->io_error); 1343 1344 kmem_free(dsa, sizeof (*dsa)); 1345 } 1346 1347 static int 1348 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, 1349 zio_prop_t *zp, zbookmark_t *zb) 1350 { 1351 dmu_sync_arg_t *dsa; 1352 dmu_tx_t *tx; 1353 1354 tx = dmu_tx_create(os); 1355 dmu_tx_hold_space(tx, zgd->zgd_db->db_size); 1356 if (dmu_tx_assign(tx, TXG_WAIT) != 0) { 1357 dmu_tx_abort(tx); 1358 /* Make zl_get_data do txg_waited_synced() */ 1359 return (SET_ERROR(EIO)); 1360 } 1361 1362 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1363 dsa->dsa_dr = NULL; 1364 dsa->dsa_done = done; 1365 dsa->dsa_zgd = zgd; 1366 dsa->dsa_tx = tx; 1367 1368 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, 1369 zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp, 1370 dmu_sync_late_arrival_ready, dmu_sync_late_arrival_done, dsa, 1371 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb)); 1372 1373 return (0); 1374 } 1375 1376 /* 1377 * Intent log support: sync the block associated with db to disk. 1378 * N.B. and XXX: the caller is responsible for making sure that the 1379 * data isn't changing while dmu_sync() is writing it. 1380 * 1381 * Return values: 1382 * 1383 * EEXIST: this txg has already been synced, so there's nothing to do. 1384 * The caller should not log the write. 1385 * 1386 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. 1387 * The caller should not log the write. 1388 * 1389 * EALREADY: this block is already in the process of being synced. 1390 * The caller should track its progress (somehow). 1391 * 1392 * EIO: could not do the I/O. 1393 * The caller should do a txg_wait_synced(). 1394 * 1395 * 0: the I/O has been initiated. 1396 * The caller should log this blkptr in the done callback. 1397 * It is possible that the I/O will fail, in which case 1398 * the error will be reported to the done callback and 1399 * propagated to pio from zio_done(). 1400 */ 1401 int 1402 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) 1403 { 1404 blkptr_t *bp = zgd->zgd_bp; 1405 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db; 1406 objset_t *os = db->db_objset; 1407 dsl_dataset_t *ds = os->os_dsl_dataset; 1408 dbuf_dirty_record_t *dr; 1409 dmu_sync_arg_t *dsa; 1410 zbookmark_t zb; 1411 zio_prop_t zp; 1412 dnode_t *dn; 1413 1414 ASSERT(pio != NULL); 1415 ASSERT(txg != 0); 1416 1417 SET_BOOKMARK(&zb, ds->ds_object, 1418 db->db.db_object, db->db_level, db->db_blkid); 1419 1420 DB_DNODE_ENTER(db); 1421 dn = DB_DNODE(db); 1422 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp, txg); 1423 DB_DNODE_EXIT(db); 1424 1425 /* 1426 * If we're frozen (running ziltest), we always need to generate a bp. 1427 */ 1428 if (txg > spa_freeze_txg(os->os_spa)) 1429 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1430 1431 /* 1432 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf() 1433 * and us. If we determine that this txg is not yet syncing, 1434 * but it begins to sync a moment later, that's OK because the 1435 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx. 1436 */ 1437 mutex_enter(&db->db_mtx); 1438 1439 if (txg <= spa_last_synced_txg(os->os_spa)) { 1440 /* 1441 * This txg has already synced. There's nothing to do. 1442 */ 1443 mutex_exit(&db->db_mtx); 1444 return (SET_ERROR(EEXIST)); 1445 } 1446 1447 if (txg <= spa_syncing_txg(os->os_spa)) { 1448 /* 1449 * This txg is currently syncing, so we can't mess with 1450 * the dirty record anymore; just write a new log block. 1451 */ 1452 mutex_exit(&db->db_mtx); 1453 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); 1454 } 1455 1456 dr = db->db_last_dirty; 1457 while (dr && dr->dr_txg != txg) 1458 dr = dr->dr_next; 1459 1460 if (dr == NULL) { 1461 /* 1462 * There's no dr for this dbuf, so it must have been freed. 1463 * There's no need to log writes to freed blocks, so we're done. 1464 */ 1465 mutex_exit(&db->db_mtx); 1466 return (SET_ERROR(ENOENT)); 1467 } 1468 1469 ASSERT(dr->dr_next == NULL || dr->dr_next->dr_txg < txg); 1470 1471 /* 1472 * Assume the on-disk data is X, the current syncing data is Y, 1473 * and the current in-memory data is Z (currently in dmu_sync). 1474 * X and Z are identical but Y is has been modified. Normally, 1475 * when X and Z are the same we will perform a nopwrite but if Y 1476 * is different we must disable nopwrite since the resulting write 1477 * of Y to disk can free the block containing X. If we allowed a 1478 * nopwrite to occur the block pointing to Z would reference a freed 1479 * block. Since this is a rare case we simplify this by disabling 1480 * nopwrite if the current dmu_sync-ing dbuf has been modified in 1481 * a previous transaction. 1482 */ 1483 if (dr->dr_next) 1484 zp.zp_nopwrite = B_FALSE; 1485 1486 ASSERT(dr->dr_txg == txg); 1487 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC || 1488 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { 1489 /* 1490 * We have already issued a sync write for this buffer, 1491 * or this buffer has already been synced. It could not 1492 * have been dirtied since, or we would have cleared the state. 1493 */ 1494 mutex_exit(&db->db_mtx); 1495 return (SET_ERROR(EALREADY)); 1496 } 1497 1498 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); 1499 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; 1500 mutex_exit(&db->db_mtx); 1501 1502 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); 1503 dsa->dsa_dr = dr; 1504 dsa->dsa_done = done; 1505 dsa->dsa_zgd = zgd; 1506 dsa->dsa_tx = NULL; 1507 1508 zio_nowait(arc_write(pio, os->os_spa, txg, 1509 bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db), &zp, 1510 dmu_sync_ready, dmu_sync_done, dsa, 1511 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb)); 1512 1513 return (0); 1514 } 1515 1516 int 1517 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, 1518 dmu_tx_t *tx) 1519 { 1520 dnode_t *dn; 1521 int err; 1522 1523 err = dnode_hold(os, object, FTAG, &dn); 1524 if (err) 1525 return (err); 1526 err = dnode_set_blksz(dn, size, ibs, tx); 1527 dnode_rele(dn, FTAG); 1528 return (err); 1529 } 1530 1531 void 1532 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, 1533 dmu_tx_t *tx) 1534 { 1535 dnode_t *dn; 1536 1537 /* XXX assumes dnode_hold will not get an i/o error */ 1538 (void) dnode_hold(os, object, FTAG, &dn); 1539 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS); 1540 dn->dn_checksum = checksum; 1541 dnode_setdirty(dn, tx); 1542 dnode_rele(dn, FTAG); 1543 } 1544 1545 void 1546 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, 1547 dmu_tx_t *tx) 1548 { 1549 dnode_t *dn; 1550 1551 /* XXX assumes dnode_hold will not get an i/o error */ 1552 (void) dnode_hold(os, object, FTAG, &dn); 1553 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS); 1554 dn->dn_compress = compress; 1555 dnode_setdirty(dn, tx); 1556 dnode_rele(dn, FTAG); 1557 } 1558 1559 int zfs_mdcomp_disable = 0; 1560 int zfs_mdcomp_lz4 = 0; 1561 1562 void 1563 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp, 1564 uint64_t txg) 1565 { 1566 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET; 1567 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) || 1568 (wp & WP_SPILL)); 1569 enum zio_checksum checksum = os->os_checksum; 1570 enum zio_compress compress = os->os_compress; 1571 enum zio_checksum dedup_checksum = os->os_dedup_checksum; 1572 boolean_t dedup = B_FALSE; 1573 boolean_t nopwrite = B_FALSE; 1574 boolean_t dedup_verify = os->os_dedup_verify; 1575 int copies = os->os_copies; 1576 1577 /* 1578 * We maintain different write policies for each of the following 1579 * types of data: 1580 * 1. metadata 1581 * 2. preallocated blocks (i.e. level-0 blocks of a dump device) 1582 * 3. all other level 0 blocks 1583 */ 1584 if (ismd) { 1585 /* 1586 * XXX -- we should design a compression algorithm 1587 * that specializes in arrays of bps. 1588 */ 1589 if (zfs_mdcomp_disable) 1590 compress = ZIO_COMPRESS_EMPTY; 1591 else if (zfs_mdcomp_lz4 && os->os_spa != NULL) { 1592 zfeature_info_t *feat = &spa_feature_table 1593 [SPA_FEATURE_LZ4_COMPRESS]; 1594 1595 if (spa_feature_is_active(os->os_spa, feat)) 1596 compress = ZIO_COMPRESS_LZ4; 1597 else if (spa_feature_is_enabled(os->os_spa, feat)) { 1598 dmu_tx_t *tx; 1599 1600 tx = dmu_tx_create_assigned( 1601 spa_get_dsl(os->os_spa), txg); 1602 spa_feature_incr(os->os_spa, feat, tx); 1603 dmu_tx_commit(tx); 1604 compress = ZIO_COMPRESS_LZ4; 1605 } else 1606 compress = ZIO_COMPRESS_LZJB; 1607 } else 1608 compress = ZIO_COMPRESS_LZJB; 1609 1610 /* 1611 * Metadata always gets checksummed. If the data 1612 * checksum is multi-bit correctable, and it's not a 1613 * ZBT-style checksum, then it's suitable for metadata 1614 * as well. Otherwise, the metadata checksum defaults 1615 * to fletcher4. 1616 */ 1617 if (zio_checksum_table[checksum].ci_correctable < 1 || 1618 zio_checksum_table[checksum].ci_eck) 1619 checksum = ZIO_CHECKSUM_FLETCHER_4; 1620 } else if (wp & WP_NOFILL) { 1621 ASSERT(level == 0); 1622 1623 /* 1624 * If we're writing preallocated blocks, we aren't actually 1625 * writing them so don't set any policy properties. These 1626 * blocks are currently only used by an external subsystem 1627 * outside of zfs (i.e. dump) and not written by the zio 1628 * pipeline. 1629 */ 1630 compress = ZIO_COMPRESS_OFF; 1631 checksum = ZIO_CHECKSUM_OFF; 1632 } else { 1633 compress = zio_compress_select(dn->dn_compress, compress); 1634 1635 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ? 1636 zio_checksum_select(dn->dn_checksum, checksum) : 1637 dedup_checksum; 1638 1639 /* 1640 * Determine dedup setting. If we are in dmu_sync(), 1641 * we won't actually dedup now because that's all 1642 * done in syncing context; but we do want to use the 1643 * dedup checkum. If the checksum is not strong 1644 * enough to ensure unique signatures, force 1645 * dedup_verify. 1646 */ 1647 if (dedup_checksum != ZIO_CHECKSUM_OFF) { 1648 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE; 1649 if (!zio_checksum_table[checksum].ci_dedup) 1650 dedup_verify = B_TRUE; 1651 } 1652 1653 /* 1654 * Enable nopwrite if we have a cryptographically secure 1655 * checksum that has no known collisions (i.e. SHA-256) 1656 * and compression is enabled. We don't enable nopwrite if 1657 * dedup is enabled as the two features are mutually exclusive. 1658 */ 1659 nopwrite = (!dedup && zio_checksum_table[checksum].ci_dedup && 1660 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled); 1661 } 1662 1663 zp->zp_checksum = checksum; 1664 zp->zp_compress = compress; 1665 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type; 1666 zp->zp_level = level; 1667 zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa)); 1668 zp->zp_dedup = dedup; 1669 zp->zp_dedup_verify = dedup && dedup_verify; 1670 zp->zp_nopwrite = nopwrite; 1671 } 1672 1673 int 1674 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) 1675 { 1676 dnode_t *dn; 1677 int i, err; 1678 1679 err = dnode_hold(os, object, FTAG, &dn); 1680 if (err) 1681 return (err); 1682 /* 1683 * Sync any current changes before 1684 * we go trundling through the block pointers. 1685 */ 1686 for (i = 0; i < TXG_SIZE; i++) { 1687 if (list_link_active(&dn->dn_dirty_link[i])) 1688 break; 1689 } 1690 if (i != TXG_SIZE) { 1691 dnode_rele(dn, FTAG); 1692 txg_wait_synced(dmu_objset_pool(os), 0); 1693 err = dnode_hold(os, object, FTAG, &dn); 1694 if (err) 1695 return (err); 1696 } 1697 1698 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); 1699 dnode_rele(dn, FTAG); 1700 1701 return (err); 1702 } 1703 1704 void 1705 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) 1706 { 1707 dnode_phys_t *dnp; 1708 1709 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1710 mutex_enter(&dn->dn_mtx); 1711 1712 dnp = dn->dn_phys; 1713 1714 doi->doi_data_block_size = dn->dn_datablksz; 1715 doi->doi_metadata_block_size = dn->dn_indblkshift ? 1716 1ULL << dn->dn_indblkshift : 0; 1717 doi->doi_type = dn->dn_type; 1718 doi->doi_bonus_type = dn->dn_bonustype; 1719 doi->doi_bonus_size = dn->dn_bonuslen; 1720 doi->doi_indirection = dn->dn_nlevels; 1721 doi->doi_checksum = dn->dn_checksum; 1722 doi->doi_compress = dn->dn_compress; 1723 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9; 1724 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz; 1725 doi->doi_fill_count = 0; 1726 for (int i = 0; i < dnp->dn_nblkptr; i++) 1727 doi->doi_fill_count += dnp->dn_blkptr[i].blk_fill; 1728 1729 mutex_exit(&dn->dn_mtx); 1730 rw_exit(&dn->dn_struct_rwlock); 1731 } 1732 1733 /* 1734 * Get information on a DMU object. 1735 * If doi is NULL, just indicates whether the object exists. 1736 */ 1737 int 1738 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) 1739 { 1740 dnode_t *dn; 1741 int err = dnode_hold(os, object, FTAG, &dn); 1742 1743 if (err) 1744 return (err); 1745 1746 if (doi != NULL) 1747 dmu_object_info_from_dnode(dn, doi); 1748 1749 dnode_rele(dn, FTAG); 1750 return (0); 1751 } 1752 1753 /* 1754 * As above, but faster; can be used when you have a held dbuf in hand. 1755 */ 1756 void 1757 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi) 1758 { 1759 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 1760 1761 DB_DNODE_ENTER(db); 1762 dmu_object_info_from_dnode(DB_DNODE(db), doi); 1763 DB_DNODE_EXIT(db); 1764 } 1765 1766 /* 1767 * Faster still when you only care about the size. 1768 * This is specifically optimized for zfs_getattr(). 1769 */ 1770 void 1771 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize, 1772 u_longlong_t *nblk512) 1773 { 1774 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; 1775 dnode_t *dn; 1776 1777 DB_DNODE_ENTER(db); 1778 dn = DB_DNODE(db); 1779 1780 *blksize = dn->dn_datablksz; 1781 /* add 1 for dnode space */ 1782 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> 1783 SPA_MINBLOCKSHIFT) + 1; 1784 DB_DNODE_EXIT(db); 1785 } 1786 1787 void 1788 byteswap_uint64_array(void *vbuf, size_t size) 1789 { 1790 uint64_t *buf = vbuf; 1791 size_t count = size >> 3; 1792 int i; 1793 1794 ASSERT((size & 7) == 0); 1795 1796 for (i = 0; i < count; i++) 1797 buf[i] = BSWAP_64(buf[i]); 1798 } 1799 1800 void 1801 byteswap_uint32_array(void *vbuf, size_t size) 1802 { 1803 uint32_t *buf = vbuf; 1804 size_t count = size >> 2; 1805 int i; 1806 1807 ASSERT((size & 3) == 0); 1808 1809 for (i = 0; i < count; i++) 1810 buf[i] = BSWAP_32(buf[i]); 1811 } 1812 1813 void 1814 byteswap_uint16_array(void *vbuf, size_t size) 1815 { 1816 uint16_t *buf = vbuf; 1817 size_t count = size >> 1; 1818 int i; 1819 1820 ASSERT((size & 1) == 0); 1821 1822 for (i = 0; i < count; i++) 1823 buf[i] = BSWAP_16(buf[i]); 1824 } 1825 1826 /* ARGSUSED */ 1827 void 1828 byteswap_uint8_array(void *vbuf, size_t size) 1829 { 1830 } 1831 1832 void 1833 dmu_init(void) 1834 { 1835 zfs_dbgmsg_init(); 1836 sa_cache_init(); 1837 xuio_stat_init(); 1838 dmu_objset_init(); 1839 dnode_init(); 1840 dbuf_init(); 1841 zfetch_init(); 1842 l2arc_init(); 1843 arc_init(); 1844 } 1845 1846 void 1847 dmu_fini(void) 1848 { 1849 arc_fini(); 1850 l2arc_fini(); 1851 zfetch_fini(); 1852 dbuf_fini(); 1853 dnode_fini(); 1854 dmu_objset_fini(); 1855 xuio_stat_fini(); 1856 sa_cache_fini(); 1857 zfs_dbgmsg_fini(); 1858 }