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) 2012, 2016 by Delphix. All rights reserved. 24 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 25 * Copyright (c) 2014 Integros [integros.com] 26 */ 27 28 #include <sys/zfs_context.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/dmu.h> 32 #include <sys/dmu_impl.h> 33 #include <sys/dmu_tx.h> 34 #include <sys/dmu_objset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_dataset.h> 37 #include <sys/spa.h> 38 #include <sys/zio.h> 39 #include <sys/dmu_zfetch.h> 40 #include <sys/range_tree.h> 41 42 static kmem_cache_t *dnode_cache; 43 /* 44 * Define DNODE_STATS to turn on statistic gathering. By default, it is only 45 * turned on when DEBUG is also defined. 46 */ 47 #ifdef DEBUG 48 #define DNODE_STATS 49 #endif /* DEBUG */ 50 51 #ifdef DNODE_STATS 52 #define DNODE_STAT_ADD(stat) ((stat)++) 53 #else 54 #define DNODE_STAT_ADD(stat) /* nothing */ 55 #endif /* DNODE_STATS */ 56 57 static dnode_phys_t dnode_phys_zero; 58 59 int zfs_default_bs = SPA_MINBLOCKSHIFT; 60 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 61 62 #ifdef illumos 63 static kmem_cbrc_t dnode_move(void *, void *, size_t, void *); 64 #endif 65 66 static int 67 dbuf_compare(const void *x1, const void *x2) 68 { 69 const dmu_buf_impl_t *d1 = x1; 70 const dmu_buf_impl_t *d2 = x2; 71 72 if (d1->db_level < d2->db_level) { 73 return (-1); 74 } 75 if (d1->db_level > d2->db_level) { 76 return (1); 77 } 78 79 if (d1->db_blkid < d2->db_blkid) { 80 return (-1); 81 } 82 if (d1->db_blkid > d2->db_blkid) { 83 return (1); 84 } 85 86 if (d1->db_state == DB_SEARCH) { 87 ASSERT3S(d2->db_state, !=, DB_SEARCH); 88 return (-1); 89 } else if (d2->db_state == DB_SEARCH) { 90 ASSERT3S(d1->db_state, !=, DB_SEARCH); 91 return (1); 92 } 93 94 if ((uintptr_t)d1 < (uintptr_t)d2) { 95 return (-1); 96 } 97 if ((uintptr_t)d1 > (uintptr_t)d2) { 98 return (1); 99 } 100 return (0); 101 } 102 103 /* ARGSUSED */ 104 static int 105 dnode_cons(void *arg, void *unused, int kmflag) 106 { 107 dnode_t *dn = arg; 108 int i; 109 110 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 111 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 112 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 113 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 114 115 /* 116 * Every dbuf has a reference, and dropping a tracked reference is 117 * O(number of references), so don't track dn_holds. 118 */ 119 refcount_create_untracked(&dn->dn_holds); 120 refcount_create(&dn->dn_tx_holds); 121 list_link_init(&dn->dn_link); 122 123 bzero(&dn->dn_next_nblkptr[0], sizeof (dn->dn_next_nblkptr)); 124 bzero(&dn->dn_next_nlevels[0], sizeof (dn->dn_next_nlevels)); 125 bzero(&dn->dn_next_indblkshift[0], sizeof (dn->dn_next_indblkshift)); 126 bzero(&dn->dn_next_bonustype[0], sizeof (dn->dn_next_bonustype)); 127 bzero(&dn->dn_rm_spillblk[0], sizeof (dn->dn_rm_spillblk)); 128 bzero(&dn->dn_next_bonuslen[0], sizeof (dn->dn_next_bonuslen)); 129 bzero(&dn->dn_next_blksz[0], sizeof (dn->dn_next_blksz)); 130 131 for (i = 0; i < TXG_SIZE; i++) { 132 list_link_init(&dn->dn_dirty_link[i]); 133 dn->dn_free_ranges[i] = NULL; 134 list_create(&dn->dn_dirty_records[i], 135 sizeof (dbuf_dirty_record_t), 136 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 137 } 138 139 dn->dn_allocated_txg = 0; 140 dn->dn_free_txg = 0; 141 dn->dn_assigned_txg = 0; 142 dn->dn_dirtyctx = 0; 143 dn->dn_dirtyctx_firstset = NULL; 144 dn->dn_bonus = NULL; 145 dn->dn_have_spill = B_FALSE; 146 dn->dn_zio = NULL; 147 dn->dn_oldused = 0; 148 dn->dn_oldflags = 0; 149 dn->dn_olduid = 0; 150 dn->dn_oldgid = 0; 151 dn->dn_newuid = 0; 152 dn->dn_newgid = 0; 153 dn->dn_id_flags = 0; 154 155 dn->dn_dbufs_count = 0; 156 avl_create(&dn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 157 offsetof(dmu_buf_impl_t, db_link)); 158 159 dn->dn_moved = 0; 160 POINTER_INVALIDATE(&dn->dn_objset); 161 return (0); 162 } 163 164 /* ARGSUSED */ 165 static void 166 dnode_dest(void *arg, void *unused) 167 { 168 int i; 169 dnode_t *dn = arg; 170 171 rw_destroy(&dn->dn_struct_rwlock); 172 mutex_destroy(&dn->dn_mtx); 173 mutex_destroy(&dn->dn_dbufs_mtx); 174 cv_destroy(&dn->dn_notxholds); 175 refcount_destroy(&dn->dn_holds); 176 refcount_destroy(&dn->dn_tx_holds); 177 ASSERT(!list_link_active(&dn->dn_link)); 178 179 for (i = 0; i < TXG_SIZE; i++) { 180 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 181 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 182 list_destroy(&dn->dn_dirty_records[i]); 183 ASSERT0(dn->dn_next_nblkptr[i]); 184 ASSERT0(dn->dn_next_nlevels[i]); 185 ASSERT0(dn->dn_next_indblkshift[i]); 186 ASSERT0(dn->dn_next_bonustype[i]); 187 ASSERT0(dn->dn_rm_spillblk[i]); 188 ASSERT0(dn->dn_next_bonuslen[i]); 189 ASSERT0(dn->dn_next_blksz[i]); 190 } 191 192 ASSERT0(dn->dn_allocated_txg); 193 ASSERT0(dn->dn_free_txg); 194 ASSERT0(dn->dn_assigned_txg); 195 ASSERT0(dn->dn_dirtyctx); 196 ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL); 197 ASSERT3P(dn->dn_bonus, ==, NULL); 198 ASSERT(!dn->dn_have_spill); 199 ASSERT3P(dn->dn_zio, ==, NULL); 200 ASSERT0(dn->dn_oldused); 201 ASSERT0(dn->dn_oldflags); 202 ASSERT0(dn->dn_olduid); 203 ASSERT0(dn->dn_oldgid); 204 ASSERT0(dn->dn_newuid); 205 ASSERT0(dn->dn_newgid); 206 ASSERT0(dn->dn_id_flags); 207 208 ASSERT0(dn->dn_dbufs_count); 209 avl_destroy(&dn->dn_dbufs); 210 } 211 212 void 213 dnode_init(void) 214 { 215 ASSERT(dnode_cache == NULL); 216 dnode_cache = kmem_cache_create("dnode_t", 217 sizeof (dnode_t), 218 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 219 kmem_cache_set_move(dnode_cache, dnode_move); 220 } 221 222 void 223 dnode_fini(void) 224 { 225 kmem_cache_destroy(dnode_cache); 226 dnode_cache = NULL; 227 } 228 229 230 #ifdef ZFS_DEBUG 231 void 232 dnode_verify(dnode_t *dn) 233 { 234 int drop_struct_lock = FALSE; 235 236 ASSERT(dn->dn_phys); 237 ASSERT(dn->dn_objset); 238 ASSERT(dn->dn_handle->dnh_dnode == dn); 239 240 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 241 242 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 243 return; 244 245 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 246 rw_enter(&dn->dn_struct_rwlock, RW_READER); 247 drop_struct_lock = TRUE; 248 } 249 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 250 int i; 251 ASSERT3U(dn->dn_indblkshift, >=, 0); 252 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 253 if (dn->dn_datablkshift) { 254 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 255 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 256 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 257 } 258 ASSERT3U(dn->dn_nlevels, <=, 30); 259 ASSERT(DMU_OT_IS_VALID(dn->dn_type)); 260 ASSERT3U(dn->dn_nblkptr, >=, 1); 261 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 262 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 263 ASSERT3U(dn->dn_datablksz, ==, 264 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 265 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 266 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 267 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 268 for (i = 0; i < TXG_SIZE; i++) { 269 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 270 } 271 } 272 if (dn->dn_phys->dn_type != DMU_OT_NONE) 273 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 274 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 275 if (dn->dn_dbuf != NULL) { 276 ASSERT3P(dn->dn_phys, ==, 277 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 278 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 279 } 280 if (drop_struct_lock) 281 rw_exit(&dn->dn_struct_rwlock); 282 } 283 #endif 284 285 void 286 dnode_byteswap(dnode_phys_t *dnp) 287 { 288 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 289 int i; 290 291 if (dnp->dn_type == DMU_OT_NONE) { 292 bzero(dnp, sizeof (dnode_phys_t)); 293 return; 294 } 295 296 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 297 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 298 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 299 dnp->dn_used = BSWAP_64(dnp->dn_used); 300 301 /* 302 * dn_nblkptr is only one byte, so it's OK to read it in either 303 * byte order. We can't read dn_bouslen. 304 */ 305 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 306 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 307 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 308 buf64[i] = BSWAP_64(buf64[i]); 309 310 /* 311 * OK to check dn_bonuslen for zero, because it won't matter if 312 * we have the wrong byte order. This is necessary because the 313 * dnode dnode is smaller than a regular dnode. 314 */ 315 if (dnp->dn_bonuslen != 0) { 316 /* 317 * Note that the bonus length calculated here may be 318 * longer than the actual bonus buffer. This is because 319 * we always put the bonus buffer after the last block 320 * pointer (instead of packing it against the end of the 321 * dnode buffer). 322 */ 323 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 324 size_t len = DN_MAX_BONUSLEN - off; 325 ASSERT(DMU_OT_IS_VALID(dnp->dn_bonustype)); 326 dmu_object_byteswap_t byteswap = 327 DMU_OT_BYTESWAP(dnp->dn_bonustype); 328 dmu_ot_byteswap[byteswap].ob_func(dnp->dn_bonus + off, len); 329 } 330 331 /* Swap SPILL block if we have one */ 332 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 333 byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t)); 334 335 } 336 337 void 338 dnode_buf_byteswap(void *vbuf, size_t size) 339 { 340 dnode_phys_t *buf = vbuf; 341 int i; 342 343 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 344 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 345 346 size >>= DNODE_SHIFT; 347 for (i = 0; i < size; i++) { 348 dnode_byteswap(buf); 349 buf++; 350 } 351 } 352 353 void 354 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 355 { 356 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 357 358 dnode_setdirty(dn, tx); 359 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 360 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 361 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 362 dn->dn_bonuslen = newsize; 363 if (newsize == 0) 364 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 365 else 366 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 367 rw_exit(&dn->dn_struct_rwlock); 368 } 369 370 void 371 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 372 { 373 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 374 dnode_setdirty(dn, tx); 375 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 376 dn->dn_bonustype = newtype; 377 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 378 rw_exit(&dn->dn_struct_rwlock); 379 } 380 381 void 382 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 383 { 384 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 385 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 386 dnode_setdirty(dn, tx); 387 dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; 388 dn->dn_have_spill = B_FALSE; 389 } 390 391 static void 392 dnode_setdblksz(dnode_t *dn, int size) 393 { 394 ASSERT0(P2PHASE(size, SPA_MINBLOCKSIZE)); 395 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 396 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 397 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 398 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 399 dn->dn_datablksz = size; 400 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 401 dn->dn_datablkshift = ISP2(size) ? highbit64(size - 1) : 0; 402 } 403 404 static dnode_t * 405 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 406 uint64_t object, dnode_handle_t *dnh) 407 { 408 dnode_t *dn; 409 410 dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 411 ASSERT(!POINTER_IS_VALID(dn->dn_objset)); 412 dn->dn_moved = 0; 413 414 /* 415 * Defer setting dn_objset until the dnode is ready to be a candidate 416 * for the dnode_move() callback. 417 */ 418 dn->dn_object = object; 419 dn->dn_dbuf = db; 420 dn->dn_handle = dnh; 421 dn->dn_phys = dnp; 422 423 if (dnp->dn_datablkszsec) { 424 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 425 } else { 426 dn->dn_datablksz = 0; 427 dn->dn_datablkszsec = 0; 428 dn->dn_datablkshift = 0; 429 } 430 dn->dn_indblkshift = dnp->dn_indblkshift; 431 dn->dn_nlevels = dnp->dn_nlevels; 432 dn->dn_type = dnp->dn_type; 433 dn->dn_nblkptr = dnp->dn_nblkptr; 434 dn->dn_checksum = dnp->dn_checksum; 435 dn->dn_compress = dnp->dn_compress; 436 dn->dn_bonustype = dnp->dn_bonustype; 437 dn->dn_bonuslen = dnp->dn_bonuslen; 438 dn->dn_maxblkid = dnp->dn_maxblkid; 439 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 440 dn->dn_id_flags = 0; 441 442 dmu_zfetch_init(&dn->dn_zfetch, dn); 443 444 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 445 446 mutex_enter(&os->os_lock); 447 if (dnh->dnh_dnode != NULL) { 448 /* Lost the allocation race. */ 449 mutex_exit(&os->os_lock); 450 #ifdef __NetBSD__ 451 dmu_zfetch_fini(&dn->dn_zfetch); 452 #endif 453 kmem_cache_free(dnode_cache, dn); 454 return (dnh->dnh_dnode); 455 } 456 457 /* 458 * Exclude special dnodes from os_dnodes so an empty os_dnodes 459 * signifies that the special dnodes have no references from 460 * their children (the entries in os_dnodes). This allows 461 * dnode_destroy() to easily determine if the last child has 462 * been removed and then complete eviction of the objset. 463 */ 464 if (!DMU_OBJECT_IS_SPECIAL(object)) 465 list_insert_head(&os->os_dnodes, dn); 466 membar_producer(); 467 468 /* 469 * Everything else must be valid before assigning dn_objset 470 * makes the dnode eligible for dnode_move(). 471 */ 472 dn->dn_objset = os; 473 474 dnh->dnh_dnode = dn; 475 mutex_exit(&os->os_lock); 476 477 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 478 return (dn); 479 } 480 481 /* 482 * Caller must be holding the dnode handle, which is released upon return. 483 */ 484 static void 485 dnode_destroy(dnode_t *dn) 486 { 487 objset_t *os = dn->dn_objset; 488 boolean_t complete_os_eviction = B_FALSE; 489 490 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 491 492 mutex_enter(&os->os_lock); 493 POINTER_INVALIDATE(&dn->dn_objset); 494 if (!DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 495 list_remove(&os->os_dnodes, dn); 496 complete_os_eviction = 497 list_is_empty(&os->os_dnodes) && 498 list_link_active(&os->os_evicting_node); 499 } 500 mutex_exit(&os->os_lock); 501 502 /* the dnode can no longer move, so we can release the handle */ 503 zrl_remove(&dn->dn_handle->dnh_zrlock); 504 505 dn->dn_allocated_txg = 0; 506 dn->dn_free_txg = 0; 507 dn->dn_assigned_txg = 0; 508 509 dn->dn_dirtyctx = 0; 510 if (dn->dn_dirtyctx_firstset != NULL) { 511 kmem_free(dn->dn_dirtyctx_firstset, 1); 512 dn->dn_dirtyctx_firstset = NULL; 513 } 514 if (dn->dn_bonus != NULL) { 515 mutex_enter(&dn->dn_bonus->db_mtx); 516 dbuf_destroy(dn->dn_bonus); 517 dn->dn_bonus = NULL; 518 } 519 dn->dn_zio = NULL; 520 521 dn->dn_have_spill = B_FALSE; 522 dn->dn_oldused = 0; 523 dn->dn_oldflags = 0; 524 dn->dn_olduid = 0; 525 dn->dn_oldgid = 0; 526 dn->dn_newuid = 0; 527 dn->dn_newgid = 0; 528 dn->dn_id_flags = 0; 529 530 dmu_zfetch_fini(&dn->dn_zfetch); 531 kmem_cache_free(dnode_cache, dn); 532 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 533 534 if (complete_os_eviction) 535 dmu_objset_evict_done(os); 536 } 537 538 void 539 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 540 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 541 { 542 int i; 543 544 ASSERT3U(blocksize, <=, 545 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 546 if (blocksize == 0) 547 blocksize = 1 << zfs_default_bs; 548 else 549 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 550 551 if (ibs == 0) 552 ibs = zfs_default_ibs; 553 554 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 555 556 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 557 dn->dn_object, tx->tx_txg, blocksize, ibs); 558 559 ASSERT(dn->dn_type == DMU_OT_NONE); 560 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 561 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 562 ASSERT(ot != DMU_OT_NONE); 563 ASSERT(DMU_OT_IS_VALID(ot)); 564 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 565 (bonustype == DMU_OT_SA && bonuslen == 0) || 566 (bonustype != DMU_OT_NONE && bonuslen != 0)); 567 ASSERT(DMU_OT_IS_VALID(bonustype)); 568 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 569 ASSERT(dn->dn_type == DMU_OT_NONE); 570 ASSERT0(dn->dn_maxblkid); 571 ASSERT0(dn->dn_allocated_txg); 572 ASSERT0(dn->dn_assigned_txg); 573 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 574 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 575 ASSERT(avl_is_empty(&dn->dn_dbufs)); 576 577 for (i = 0; i < TXG_SIZE; i++) { 578 ASSERT0(dn->dn_next_nblkptr[i]); 579 ASSERT0(dn->dn_next_nlevels[i]); 580 ASSERT0(dn->dn_next_indblkshift[i]); 581 ASSERT0(dn->dn_next_bonuslen[i]); 582 ASSERT0(dn->dn_next_bonustype[i]); 583 ASSERT0(dn->dn_rm_spillblk[i]); 584 ASSERT0(dn->dn_next_blksz[i]); 585 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 586 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 587 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 588 } 589 590 dn->dn_type = ot; 591 dnode_setdblksz(dn, blocksize); 592 dn->dn_indblkshift = ibs; 593 dn->dn_nlevels = 1; 594 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 595 dn->dn_nblkptr = 1; 596 else 597 dn->dn_nblkptr = 1 + 598 ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 599 dn->dn_bonustype = bonustype; 600 dn->dn_bonuslen = bonuslen; 601 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 602 dn->dn_compress = ZIO_COMPRESS_INHERIT; 603 dn->dn_dirtyctx = 0; 604 605 dn->dn_free_txg = 0; 606 if (dn->dn_dirtyctx_firstset) { 607 kmem_free(dn->dn_dirtyctx_firstset, 1); 608 dn->dn_dirtyctx_firstset = NULL; 609 } 610 611 dn->dn_allocated_txg = tx->tx_txg; 612 dn->dn_id_flags = 0; 613 614 dnode_setdirty(dn, tx); 615 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 616 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 617 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 618 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 619 } 620 621 void 622 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 623 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 624 { 625 int nblkptr; 626 627 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 628 ASSERT3U(blocksize, <=, 629 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 630 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 631 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 632 ASSERT(tx->tx_txg != 0); 633 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 634 (bonustype != DMU_OT_NONE && bonuslen != 0) || 635 (bonustype == DMU_OT_SA && bonuslen == 0)); 636 ASSERT(DMU_OT_IS_VALID(bonustype)); 637 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 638 639 /* clean up any unreferenced dbufs */ 640 dnode_evict_dbufs(dn); 641 642 dn->dn_id_flags = 0; 643 644 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 645 dnode_setdirty(dn, tx); 646 if (dn->dn_datablksz != blocksize) { 647 /* change blocksize */ 648 ASSERT(dn->dn_maxblkid == 0 && 649 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 650 dnode_block_freed(dn, 0))); 651 dnode_setdblksz(dn, blocksize); 652 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 653 } 654 if (dn->dn_bonuslen != bonuslen) 655 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 656 657 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 658 nblkptr = 1; 659 else 660 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 661 if (dn->dn_bonustype != bonustype) 662 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 663 if (dn->dn_nblkptr != nblkptr) 664 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 665 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 666 dbuf_rm_spill(dn, tx); 667 dnode_rm_spill(dn, tx); 668 } 669 rw_exit(&dn->dn_struct_rwlock); 670 671 /* change type */ 672 dn->dn_type = ot; 673 674 /* change bonus size and type */ 675 mutex_enter(&dn->dn_mtx); 676 dn->dn_bonustype = bonustype; 677 dn->dn_bonuslen = bonuslen; 678 dn->dn_nblkptr = nblkptr; 679 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 680 dn->dn_compress = ZIO_COMPRESS_INHERIT; 681 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 682 683 /* fix up the bonus db_size */ 684 if (dn->dn_bonus) { 685 dn->dn_bonus->db.db_size = 686 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 687 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 688 } 689 690 dn->dn_allocated_txg = tx->tx_txg; 691 mutex_exit(&dn->dn_mtx); 692 } 693 694 #ifdef DNODE_STATS 695 static struct { 696 uint64_t dms_dnode_invalid; 697 uint64_t dms_dnode_recheck1; 698 uint64_t dms_dnode_recheck2; 699 uint64_t dms_dnode_special; 700 uint64_t dms_dnode_handle; 701 uint64_t dms_dnode_rwlock; 702 uint64_t dms_dnode_active; 703 } dnode_move_stats; 704 #endif /* DNODE_STATS */ 705 706 static void 707 dnode_move_impl(dnode_t *odn, dnode_t *ndn) 708 { 709 int i; 710 711 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 712 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 713 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 714 ASSERT(!RW_LOCK_HELD(&odn->dn_zfetch.zf_rwlock)); 715 716 /* Copy fields. */ 717 ndn->dn_objset = odn->dn_objset; 718 ndn->dn_object = odn->dn_object; 719 ndn->dn_dbuf = odn->dn_dbuf; 720 ndn->dn_handle = odn->dn_handle; 721 ndn->dn_phys = odn->dn_phys; 722 ndn->dn_type = odn->dn_type; 723 ndn->dn_bonuslen = odn->dn_bonuslen; 724 ndn->dn_bonustype = odn->dn_bonustype; 725 ndn->dn_nblkptr = odn->dn_nblkptr; 726 ndn->dn_checksum = odn->dn_checksum; 727 ndn->dn_compress = odn->dn_compress; 728 ndn->dn_nlevels = odn->dn_nlevels; 729 ndn->dn_indblkshift = odn->dn_indblkshift; 730 ndn->dn_datablkshift = odn->dn_datablkshift; 731 ndn->dn_datablkszsec = odn->dn_datablkszsec; 732 ndn->dn_datablksz = odn->dn_datablksz; 733 ndn->dn_maxblkid = odn->dn_maxblkid; 734 bcopy(&odn->dn_next_nblkptr[0], &ndn->dn_next_nblkptr[0], 735 sizeof (odn->dn_next_nblkptr)); 736 bcopy(&odn->dn_next_nlevels[0], &ndn->dn_next_nlevels[0], 737 sizeof (odn->dn_next_nlevels)); 738 bcopy(&odn->dn_next_indblkshift[0], &ndn->dn_next_indblkshift[0], 739 sizeof (odn->dn_next_indblkshift)); 740 bcopy(&odn->dn_next_bonustype[0], &ndn->dn_next_bonustype[0], 741 sizeof (odn->dn_next_bonustype)); 742 bcopy(&odn->dn_rm_spillblk[0], &ndn->dn_rm_spillblk[0], 743 sizeof (odn->dn_rm_spillblk)); 744 bcopy(&odn->dn_next_bonuslen[0], &ndn->dn_next_bonuslen[0], 745 sizeof (odn->dn_next_bonuslen)); 746 bcopy(&odn->dn_next_blksz[0], &ndn->dn_next_blksz[0], 747 sizeof (odn->dn_next_blksz)); 748 for (i = 0; i < TXG_SIZE; i++) { 749 list_move_tail(&ndn->dn_dirty_records[i], 750 &odn->dn_dirty_records[i]); 751 } 752 bcopy(&odn->dn_free_ranges[0], &ndn->dn_free_ranges[0], 753 sizeof (odn->dn_free_ranges)); 754 ndn->dn_allocated_txg = odn->dn_allocated_txg; 755 ndn->dn_free_txg = odn->dn_free_txg; 756 ndn->dn_assigned_txg = odn->dn_assigned_txg; 757 ndn->dn_dirtyctx = odn->dn_dirtyctx; 758 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 759 ASSERT(refcount_count(&odn->dn_tx_holds) == 0); 760 refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 761 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 762 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 763 ndn->dn_dbufs_count = odn->dn_dbufs_count; 764 ndn->dn_bonus = odn->dn_bonus; 765 ndn->dn_have_spill = odn->dn_have_spill; 766 ndn->dn_zio = odn->dn_zio; 767 ndn->dn_oldused = odn->dn_oldused; 768 ndn->dn_oldflags = odn->dn_oldflags; 769 ndn->dn_olduid = odn->dn_olduid; 770 ndn->dn_oldgid = odn->dn_oldgid; 771 ndn->dn_newuid = odn->dn_newuid; 772 ndn->dn_newgid = odn->dn_newgid; 773 ndn->dn_id_flags = odn->dn_id_flags; 774 dmu_zfetch_init(&ndn->dn_zfetch, NULL); 775 list_move_tail(&ndn->dn_zfetch.zf_stream, &odn->dn_zfetch.zf_stream); 776 ndn->dn_zfetch.zf_dnode = odn->dn_zfetch.zf_dnode; 777 778 /* 779 * Update back pointers. Updating the handle fixes the back pointer of 780 * every descendant dbuf as well as the bonus dbuf. 781 */ 782 ASSERT(ndn->dn_handle->dnh_dnode == odn); 783 ndn->dn_handle->dnh_dnode = ndn; 784 if (ndn->dn_zfetch.zf_dnode == odn) { 785 ndn->dn_zfetch.zf_dnode = ndn; 786 } 787 788 /* 789 * Invalidate the original dnode by clearing all of its back pointers. 790 */ 791 odn->dn_dbuf = NULL; 792 odn->dn_handle = NULL; 793 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 794 offsetof(dmu_buf_impl_t, db_link)); 795 odn->dn_dbufs_count = 0; 796 odn->dn_bonus = NULL; 797 odn->dn_zfetch.zf_dnode = NULL; 798 799 /* 800 * Set the low bit of the objset pointer to ensure that dnode_move() 801 * recognizes the dnode as invalid in any subsequent callback. 802 */ 803 POINTER_INVALIDATE(&odn->dn_objset); 804 805 /* 806 * Satisfy the destructor. 807 */ 808 for (i = 0; i < TXG_SIZE; i++) { 809 list_create(&odn->dn_dirty_records[i], 810 sizeof (dbuf_dirty_record_t), 811 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 812 odn->dn_free_ranges[i] = NULL; 813 odn->dn_next_nlevels[i] = 0; 814 odn->dn_next_indblkshift[i] = 0; 815 odn->dn_next_bonustype[i] = 0; 816 odn->dn_rm_spillblk[i] = 0; 817 odn->dn_next_bonuslen[i] = 0; 818 odn->dn_next_blksz[i] = 0; 819 } 820 odn->dn_allocated_txg = 0; 821 odn->dn_free_txg = 0; 822 odn->dn_assigned_txg = 0; 823 odn->dn_dirtyctx = 0; 824 odn->dn_dirtyctx_firstset = NULL; 825 odn->dn_have_spill = B_FALSE; 826 odn->dn_zio = NULL; 827 odn->dn_oldused = 0; 828 odn->dn_oldflags = 0; 829 odn->dn_olduid = 0; 830 odn->dn_oldgid = 0; 831 odn->dn_newuid = 0; 832 odn->dn_newgid = 0; 833 odn->dn_id_flags = 0; 834 835 /* 836 * Mark the dnode. 837 */ 838 ndn->dn_moved = 1; 839 odn->dn_moved = (uint8_t)-1; 840 } 841 842 #ifdef illumos 843 #ifdef _KERNEL 844 /*ARGSUSED*/ 845 static kmem_cbrc_t 846 dnode_move(void *buf, void *newbuf, size_t size, void *arg) 847 { 848 dnode_t *odn = buf, *ndn = newbuf; 849 objset_t *os; 850 int64_t refcount; 851 uint32_t dbufs; 852 853 /* 854 * The dnode is on the objset's list of known dnodes if the objset 855 * pointer is valid. We set the low bit of the objset pointer when 856 * freeing the dnode to invalidate it, and the memory patterns written 857 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 858 * A newly created dnode sets the objset pointer last of all to indicate 859 * that the dnode is known and in a valid state to be moved by this 860 * function. 861 */ 862 os = odn->dn_objset; 863 if (!POINTER_IS_VALID(os)) { 864 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_invalid); 865 return (KMEM_CBRC_DONT_KNOW); 866 } 867 868 /* 869 * Ensure that the objset does not go away during the move. 870 */ 871 rw_enter(&os_lock, RW_WRITER); 872 if (os != odn->dn_objset) { 873 rw_exit(&os_lock); 874 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck1); 875 return (KMEM_CBRC_DONT_KNOW); 876 } 877 878 /* 879 * If the dnode is still valid, then so is the objset. We know that no 880 * valid objset can be freed while we hold os_lock, so we can safely 881 * ensure that the objset remains in use. 882 */ 883 mutex_enter(&os->os_lock); 884 885 /* 886 * Recheck the objset pointer in case the dnode was removed just before 887 * acquiring the lock. 888 */ 889 if (os != odn->dn_objset) { 890 mutex_exit(&os->os_lock); 891 rw_exit(&os_lock); 892 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck2); 893 return (KMEM_CBRC_DONT_KNOW); 894 } 895 896 /* 897 * At this point we know that as long as we hold os->os_lock, the dnode 898 * cannot be freed and fields within the dnode can be safely accessed. 899 * The objset listing this dnode cannot go away as long as this dnode is 900 * on its list. 901 */ 902 rw_exit(&os_lock); 903 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 904 mutex_exit(&os->os_lock); 905 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_special); 906 return (KMEM_CBRC_NO); 907 } 908 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 909 910 /* 911 * Lock the dnode handle to prevent the dnode from obtaining any new 912 * holds. This also prevents the descendant dbufs and the bonus dbuf 913 * from accessing the dnode, so that we can discount their holds. The 914 * handle is safe to access because we know that while the dnode cannot 915 * go away, neither can its handle. Once we hold dnh_zrlock, we can 916 * safely move any dnode referenced only by dbufs. 917 */ 918 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 919 mutex_exit(&os->os_lock); 920 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_handle); 921 return (KMEM_CBRC_LATER); 922 } 923 924 /* 925 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 926 * We need to guarantee that there is a hold for every dbuf in order to 927 * determine whether the dnode is actively referenced. Falsely matching 928 * a dbuf to an active hold would lead to an unsafe move. It's possible 929 * that a thread already having an active dnode hold is about to add a 930 * dbuf, and we can't compare hold and dbuf counts while the add is in 931 * progress. 932 */ 933 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 934 zrl_exit(&odn->dn_handle->dnh_zrlock); 935 mutex_exit(&os->os_lock); 936 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_rwlock); 937 return (KMEM_CBRC_LATER); 938 } 939 940 /* 941 * A dbuf may be removed (evicted) without an active dnode hold. In that 942 * case, the dbuf count is decremented under the handle lock before the 943 * dbuf's hold is released. This order ensures that if we count the hold 944 * after the dbuf is removed but before its hold is released, we will 945 * treat the unmatched hold as active and exit safely. If we count the 946 * hold before the dbuf is removed, the hold is discounted, and the 947 * removal is blocked until the move completes. 948 */ 949 refcount = refcount_count(&odn->dn_holds); 950 ASSERT(refcount >= 0); 951 dbufs = odn->dn_dbufs_count; 952 953 /* We can't have more dbufs than dnode holds. */ 954 ASSERT3U(dbufs, <=, refcount); 955 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 956 uint32_t, dbufs); 957 958 if (refcount > dbufs) { 959 rw_exit(&odn->dn_struct_rwlock); 960 zrl_exit(&odn->dn_handle->dnh_zrlock); 961 mutex_exit(&os->os_lock); 962 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_active); 963 return (KMEM_CBRC_LATER); 964 } 965 966 rw_exit(&odn->dn_struct_rwlock); 967 968 /* 969 * At this point we know that anyone with a hold on the dnode is not 970 * actively referencing it. The dnode is known and in a valid state to 971 * move. We're holding the locks needed to execute the critical section. 972 */ 973 dnode_move_impl(odn, ndn); 974 975 list_link_replace(&odn->dn_link, &ndn->dn_link); 976 /* If the dnode was safe to move, the refcount cannot have changed. */ 977 ASSERT(refcount == refcount_count(&ndn->dn_holds)); 978 ASSERT(dbufs == ndn->dn_dbufs_count); 979 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 980 mutex_exit(&os->os_lock); 981 982 return (KMEM_CBRC_YES); 983 } 984 #endif /* _KERNEL */ 985 #endif /* illumos */ 986 987 void 988 dnode_special_close(dnode_handle_t *dnh) 989 { 990 dnode_t *dn = dnh->dnh_dnode; 991 992 /* 993 * Wait for final references to the dnode to clear. This can 994 * only happen if the arc is asyncronously evicting state that 995 * has a hold on this dnode while we are trying to evict this 996 * dnode. 997 */ 998 while (refcount_count(&dn->dn_holds) > 0) 999 delay(1); 1000 ASSERT(dn->dn_dbuf == NULL || 1001 dmu_buf_get_user(&dn->dn_dbuf->db) == NULL); 1002 zrl_add(&dnh->dnh_zrlock); 1003 dnode_destroy(dn); /* implicit zrl_remove() */ 1004 zrl_destroy(&dnh->dnh_zrlock); 1005 dnh->dnh_dnode = NULL; 1006 } 1007 1008 void 1009 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 1010 dnode_handle_t *dnh) 1011 { 1012 dnode_t *dn; 1013 1014 dn = dnode_create(os, dnp, NULL, object, dnh); 1015 zrl_init(&dnh->dnh_zrlock); 1016 DNODE_VERIFY(dn); 1017 } 1018 1019 static void 1020 dnode_buf_evict_async(void *dbu) 1021 { 1022 dnode_children_t *children_dnodes = dbu; 1023 int i; 1024 1025 for (i = 0; i < children_dnodes->dnc_count; i++) { 1026 dnode_handle_t *dnh = &children_dnodes->dnc_children[i]; 1027 dnode_t *dn; 1028 1029 /* 1030 * The dnode handle lock guards against the dnode moving to 1031 * another valid address, so there is no need here to guard 1032 * against changes to or from NULL. 1033 */ 1034 if (dnh->dnh_dnode == NULL) { 1035 zrl_destroy(&dnh->dnh_zrlock); 1036 continue; 1037 } 1038 1039 zrl_add(&dnh->dnh_zrlock); 1040 dn = dnh->dnh_dnode; 1041 /* 1042 * If there are holds on this dnode, then there should 1043 * be holds on the dnode's containing dbuf as well; thus 1044 * it wouldn't be eligible for eviction and this function 1045 * would not have been called. 1046 */ 1047 ASSERT(refcount_is_zero(&dn->dn_holds)); 1048 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 1049 1050 dnode_destroy(dn); /* implicit zrl_remove() */ 1051 zrl_destroy(&dnh->dnh_zrlock); 1052 dnh->dnh_dnode = NULL; 1053 } 1054 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1055 children_dnodes->dnc_count * sizeof (dnode_handle_t)); 1056 } 1057 1058 /* 1059 * errors: 1060 * EINVAL - invalid object number. 1061 * EIO - i/o error. 1062 * succeeds even for free dnodes. 1063 */ 1064 int 1065 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 1066 void *tag, dnode_t **dnp) 1067 { 1068 int epb, idx, err; 1069 int drop_struct_lock = FALSE; 1070 int type; 1071 uint64_t blk; 1072 dnode_t *mdn, *dn; 1073 dmu_buf_impl_t *db; 1074 dnode_children_t *children_dnodes; 1075 dnode_handle_t *dnh; 1076 1077 /* 1078 * If you are holding the spa config lock as writer, you shouldn't 1079 * be asking the DMU to do *anything* unless it's the root pool 1080 * which may require us to read from the root filesystem while 1081 * holding some (not all) of the locks as writer. 1082 */ 1083 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1084 (spa_is_root(os->os_spa) && 1085 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1086 1087 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 1088 dn = (object == DMU_USERUSED_OBJECT) ? 1089 DMU_USERUSED_DNODE(os) : DMU_GROUPUSED_DNODE(os); 1090 if (dn == NULL) 1091 return (SET_ERROR(ENOENT)); 1092 type = dn->dn_type; 1093 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1094 return (SET_ERROR(ENOENT)); 1095 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1096 return (SET_ERROR(EEXIST)); 1097 DNODE_VERIFY(dn); 1098 (void) refcount_add(&dn->dn_holds, tag); 1099 *dnp = dn; 1100 return (0); 1101 } 1102 1103 if (object == 0 || object >= DN_MAX_OBJECT) 1104 return (SET_ERROR(EINVAL)); 1105 1106 mdn = DMU_META_DNODE(os); 1107 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1108 1109 DNODE_VERIFY(mdn); 1110 1111 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1112 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1113 drop_struct_lock = TRUE; 1114 } 1115 1116 blk = dbuf_whichblock(mdn, 0, object * sizeof (dnode_phys_t)); 1117 1118 db = dbuf_hold(mdn, blk, FTAG); 1119 if (drop_struct_lock) 1120 rw_exit(&mdn->dn_struct_rwlock); 1121 if (db == NULL) 1122 return (SET_ERROR(EIO)); 1123 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 1124 if (err) { 1125 dbuf_rele(db, FTAG); 1126 return (err); 1127 } 1128 1129 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1130 epb = db->db.db_size >> DNODE_SHIFT; 1131 1132 idx = object & (epb-1); 1133 1134 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1135 children_dnodes = dmu_buf_get_user(&db->db); 1136 if (children_dnodes == NULL) { 1137 int i; 1138 dnode_children_t *winner; 1139 children_dnodes = kmem_zalloc(sizeof (dnode_children_t) + 1140 epb * sizeof (dnode_handle_t), KM_SLEEP); 1141 children_dnodes->dnc_count = epb; 1142 dnh = &children_dnodes->dnc_children[0]; 1143 for (i = 0; i < epb; i++) { 1144 zrl_init(&dnh[i].dnh_zrlock); 1145 } 1146 dmu_buf_init_user(&children_dnodes->dnc_dbu, NULL, 1147 dnode_buf_evict_async, NULL); 1148 winner = dmu_buf_set_user(&db->db, &children_dnodes->dnc_dbu); 1149 if (winner != NULL) { 1150 1151 for (i = 0; i < epb; i++) { 1152 zrl_destroy(&dnh[i].dnh_zrlock); 1153 } 1154 1155 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1156 epb * sizeof (dnode_handle_t)); 1157 children_dnodes = winner; 1158 } 1159 } 1160 ASSERT(children_dnodes->dnc_count == epb); 1161 1162 dnh = &children_dnodes->dnc_children[idx]; 1163 zrl_add(&dnh->dnh_zrlock); 1164 dn = dnh->dnh_dnode; 1165 if (dn == NULL) { 1166 dnode_phys_t *phys = (dnode_phys_t *)db->db.db_data+idx; 1167 1168 dn = dnode_create(os, phys, db, object, dnh); 1169 } 1170 1171 mutex_enter(&dn->dn_mtx); 1172 type = dn->dn_type; 1173 if (dn->dn_free_txg || 1174 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 1175 ((flag & DNODE_MUST_BE_FREE) && 1176 (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) { 1177 mutex_exit(&dn->dn_mtx); 1178 zrl_remove(&dnh->dnh_zrlock); 1179 dbuf_rele(db, FTAG); 1180 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 1181 } 1182 if (refcount_add(&dn->dn_holds, tag) == 1) 1183 dbuf_add_ref(db, dnh); 1184 mutex_exit(&dn->dn_mtx); 1185 1186 /* Now we can rely on the hold to prevent the dnode from moving. */ 1187 zrl_remove(&dnh->dnh_zrlock); 1188 1189 DNODE_VERIFY(dn); 1190 ASSERT3P(dn->dn_dbuf, ==, db); 1191 ASSERT3U(dn->dn_object, ==, object); 1192 dbuf_rele(db, FTAG); 1193 1194 *dnp = dn; 1195 return (0); 1196 } 1197 1198 /* 1199 * Return held dnode if the object is allocated, NULL if not. 1200 */ 1201 int 1202 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 1203 { 1204 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 1205 } 1206 1207 /* 1208 * Can only add a reference if there is already at least one 1209 * reference on the dnode. Returns FALSE if unable to add a 1210 * new reference. 1211 */ 1212 boolean_t 1213 dnode_add_ref(dnode_t *dn, void *tag) 1214 { 1215 mutex_enter(&dn->dn_mtx); 1216 if (refcount_is_zero(&dn->dn_holds)) { 1217 mutex_exit(&dn->dn_mtx); 1218 return (FALSE); 1219 } 1220 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 1221 mutex_exit(&dn->dn_mtx); 1222 return (TRUE); 1223 } 1224 1225 void 1226 dnode_rele(dnode_t *dn, void *tag) 1227 { 1228 mutex_enter(&dn->dn_mtx); 1229 dnode_rele_and_unlock(dn, tag); 1230 } 1231 1232 void 1233 dnode_rele_and_unlock(dnode_t *dn, void *tag) 1234 { 1235 uint64_t refs; 1236 /* Get while the hold prevents the dnode from moving. */ 1237 dmu_buf_impl_t *db = dn->dn_dbuf; 1238 dnode_handle_t *dnh = dn->dn_handle; 1239 1240 refs = refcount_remove(&dn->dn_holds, tag); 1241 mutex_exit(&dn->dn_mtx); 1242 1243 /* 1244 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1245 * indirectly by dbuf_rele() while relying on the dnode handle to 1246 * prevent the dnode from moving, since releasing the last hold could 1247 * result in the dnode's parent dbuf evicting its dnode handles. For 1248 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1249 * other direct or indirect hold on the dnode must first drop the dnode 1250 * handle. 1251 */ 1252 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread); 1253 1254 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1255 if (refs == 0 && db != NULL) { 1256 /* 1257 * Another thread could add a hold to the dnode handle in 1258 * dnode_hold_impl() while holding the parent dbuf. Since the 1259 * hold on the parent dbuf prevents the handle from being 1260 * destroyed, the hold on the handle is OK. We can't yet assert 1261 * that the handle has zero references, but that will be 1262 * asserted anyway when the handle gets destroyed. 1263 */ 1264 dbuf_rele(db, dnh); 1265 } 1266 } 1267 1268 void 1269 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1270 { 1271 objset_t *os = dn->dn_objset; 1272 uint64_t txg = tx->tx_txg; 1273 1274 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1275 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1276 return; 1277 } 1278 1279 DNODE_VERIFY(dn); 1280 1281 #ifdef ZFS_DEBUG 1282 mutex_enter(&dn->dn_mtx); 1283 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1284 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1285 mutex_exit(&dn->dn_mtx); 1286 #endif 1287 1288 /* 1289 * Determine old uid/gid when necessary 1290 */ 1291 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1292 1293 mutex_enter(&os->os_lock); 1294 1295 /* 1296 * If we are already marked dirty, we're done. 1297 */ 1298 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1299 mutex_exit(&os->os_lock); 1300 return; 1301 } 1302 1303 ASSERT(!refcount_is_zero(&dn->dn_holds) || 1304 !avl_is_empty(&dn->dn_dbufs)); 1305 ASSERT(dn->dn_datablksz != 0); 1306 ASSERT0(dn->dn_next_bonuslen[txg&TXG_MASK]); 1307 ASSERT0(dn->dn_next_blksz[txg&TXG_MASK]); 1308 ASSERT0(dn->dn_next_bonustype[txg&TXG_MASK]); 1309 1310 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1311 dn->dn_object, txg); 1312 1313 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 1314 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 1315 } else { 1316 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 1317 } 1318 1319 mutex_exit(&os->os_lock); 1320 1321 /* 1322 * The dnode maintains a hold on its containing dbuf as 1323 * long as there are holds on it. Each instantiated child 1324 * dbuf maintains a hold on the dnode. When the last child 1325 * drops its hold, the dnode will drop its hold on the 1326 * containing dbuf. We add a "dirty hold" here so that the 1327 * dnode will hang around after we finish processing its 1328 * children. 1329 */ 1330 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1331 1332 (void) dbuf_dirty(dn->dn_dbuf, tx); 1333 1334 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1335 } 1336 1337 void 1338 dnode_free(dnode_t *dn, dmu_tx_t *tx) 1339 { 1340 int txgoff = tx->tx_txg & TXG_MASK; 1341 1342 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 1343 1344 /* we should be the only holder... hopefully */ 1345 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 1346 1347 mutex_enter(&dn->dn_mtx); 1348 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1349 mutex_exit(&dn->dn_mtx); 1350 return; 1351 } 1352 dn->dn_free_txg = tx->tx_txg; 1353 mutex_exit(&dn->dn_mtx); 1354 1355 /* 1356 * If the dnode is already dirty, it needs to be moved from 1357 * the dirty list to the free list. 1358 */ 1359 mutex_enter(&dn->dn_objset->os_lock); 1360 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 1361 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 1362 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 1363 mutex_exit(&dn->dn_objset->os_lock); 1364 } else { 1365 mutex_exit(&dn->dn_objset->os_lock); 1366 dnode_setdirty(dn, tx); 1367 } 1368 } 1369 1370 /* 1371 * Try to change the block size for the indicated dnode. This can only 1372 * succeed if there are no blocks allocated or dirty beyond first block 1373 */ 1374 int 1375 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1376 { 1377 dmu_buf_impl_t *db; 1378 int err; 1379 1380 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 1381 if (size == 0) 1382 size = SPA_MINBLOCKSIZE; 1383 else 1384 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1385 1386 if (ibs == dn->dn_indblkshift) 1387 ibs = 0; 1388 1389 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 1390 return (0); 1391 1392 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1393 1394 /* Check for any allocated blocks beyond the first */ 1395 if (dn->dn_maxblkid != 0) 1396 goto fail; 1397 1398 mutex_enter(&dn->dn_dbufs_mtx); 1399 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1400 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1401 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1402 db->db_blkid != DMU_SPILL_BLKID) { 1403 mutex_exit(&dn->dn_dbufs_mtx); 1404 goto fail; 1405 } 1406 } 1407 mutex_exit(&dn->dn_dbufs_mtx); 1408 1409 if (ibs && dn->dn_nlevels != 1) 1410 goto fail; 1411 1412 /* resize the old block */ 1413 err = dbuf_hold_impl(dn, 0, 0, TRUE, FALSE, FTAG, &db); 1414 if (err == 0) 1415 dbuf_new_size(db, size, tx); 1416 else if (err != ENOENT) 1417 goto fail; 1418 1419 dnode_setdblksz(dn, size); 1420 dnode_setdirty(dn, tx); 1421 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 1422 if (ibs) { 1423 dn->dn_indblkshift = ibs; 1424 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 1425 } 1426 /* rele after we have fixed the blocksize in the dnode */ 1427 if (db) 1428 dbuf_rele(db, FTAG); 1429 1430 rw_exit(&dn->dn_struct_rwlock); 1431 return (0); 1432 1433 fail: 1434 rw_exit(&dn->dn_struct_rwlock); 1435 return (SET_ERROR(ENOTSUP)); 1436 } 1437 1438 /* read-holding callers must not rely on the lock being continuously held */ 1439 void 1440 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 1441 { 1442 uint64_t txgoff = tx->tx_txg & TXG_MASK; 1443 int epbs, new_nlevels; 1444 uint64_t sz; 1445 1446 ASSERT(blkid != DMU_BONUS_BLKID); 1447 1448 ASSERT(have_read ? 1449 RW_READ_HELD(&dn->dn_struct_rwlock) : 1450 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 1451 1452 /* 1453 * if we have a read-lock, check to see if we need to do any work 1454 * before upgrading to a write-lock. 1455 */ 1456 if (have_read) { 1457 if (blkid <= dn->dn_maxblkid) 1458 return; 1459 1460 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 1461 rw_exit(&dn->dn_struct_rwlock); 1462 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1463 } 1464 } 1465 1466 if (blkid <= dn->dn_maxblkid) 1467 goto out; 1468 1469 dn->dn_maxblkid = blkid; 1470 1471 /* 1472 * Compute the number of levels necessary to support the new maxblkid. 1473 */ 1474 new_nlevels = 1; 1475 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1476 for (sz = dn->dn_nblkptr; 1477 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 1478 new_nlevels++; 1479 1480 if (new_nlevels > dn->dn_nlevels) { 1481 int old_nlevels = dn->dn_nlevels; 1482 dmu_buf_impl_t *db; 1483 list_t *list; 1484 dbuf_dirty_record_t *new, *dr, *dr_next; 1485 1486 dn->dn_nlevels = new_nlevels; 1487 1488 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 1489 dn->dn_next_nlevels[txgoff] = new_nlevels; 1490 1491 /* dirty the left indirects */ 1492 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 1493 ASSERT(db != NULL); 1494 new = dbuf_dirty(db, tx); 1495 dbuf_rele(db, FTAG); 1496 1497 /* transfer the dirty records to the new indirect */ 1498 mutex_enter(&dn->dn_mtx); 1499 mutex_enter(&new->dt.di.dr_mtx); 1500 list = &dn->dn_dirty_records[txgoff]; 1501 for (dr = list_head(list); dr; dr = dr_next) { 1502 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 1503 if (dr->dr_dbuf->db_level != new_nlevels-1 && 1504 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 1505 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 1506 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 1507 list_remove(&dn->dn_dirty_records[txgoff], dr); 1508 list_insert_tail(&new->dt.di.dr_children, dr); 1509 dr->dr_parent = new; 1510 } 1511 } 1512 mutex_exit(&new->dt.di.dr_mtx); 1513 mutex_exit(&dn->dn_mtx); 1514 } 1515 1516 out: 1517 if (have_read) 1518 rw_downgrade(&dn->dn_struct_rwlock); 1519 } 1520 1521 static void 1522 dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx) 1523 { 1524 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG); 1525 if (db != NULL) { 1526 dmu_buf_will_dirty(&db->db, tx); 1527 dbuf_rele(db, FTAG); 1528 } 1529 } 1530 1531 void 1532 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1533 { 1534 dmu_buf_impl_t *db; 1535 uint64_t blkoff, blkid, nblks; 1536 int blksz, blkshift, head, tail; 1537 int trunc = FALSE; 1538 int epbs; 1539 1540 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1541 blksz = dn->dn_datablksz; 1542 blkshift = dn->dn_datablkshift; 1543 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1544 1545 if (len == DMU_OBJECT_END) { 1546 len = UINT64_MAX - off; 1547 trunc = TRUE; 1548 } 1549 1550 /* 1551 * First, block align the region to free: 1552 */ 1553 if (ISP2(blksz)) { 1554 head = P2NPHASE(off, blksz); 1555 blkoff = P2PHASE(off, blksz); 1556 if ((off >> blkshift) > dn->dn_maxblkid) 1557 goto out; 1558 } else { 1559 ASSERT(dn->dn_maxblkid == 0); 1560 if (off == 0 && len >= blksz) { 1561 /* 1562 * Freeing the whole block; fast-track this request. 1563 * Note that we won't dirty any indirect blocks, 1564 * which is fine because we will be freeing the entire 1565 * file and thus all indirect blocks will be freed 1566 * by free_children(). 1567 */ 1568 blkid = 0; 1569 nblks = 1; 1570 goto done; 1571 } else if (off >= blksz) { 1572 /* Freeing past end-of-data */ 1573 goto out; 1574 } else { 1575 /* Freeing part of the block. */ 1576 head = blksz - off; 1577 ASSERT3U(head, >, 0); 1578 } 1579 blkoff = off; 1580 } 1581 /* zero out any partial block data at the start of the range */ 1582 if (head) { 1583 ASSERT3U(blkoff + head, ==, blksz); 1584 if (len < head) 1585 head = len; 1586 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off), 1587 TRUE, FALSE, FTAG, &db) == 0) { 1588 caddr_t data; 1589 1590 /* don't dirty if it isn't on disk and isn't dirty */ 1591 if (db->db_last_dirty || 1592 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1593 rw_exit(&dn->dn_struct_rwlock); 1594 dmu_buf_will_dirty(&db->db, tx); 1595 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1596 data = db->db.db_data; 1597 bzero(data + blkoff, head); 1598 } 1599 dbuf_rele(db, FTAG); 1600 } 1601 off += head; 1602 len -= head; 1603 } 1604 1605 /* If the range was less than one block, we're done */ 1606 if (len == 0) 1607 goto out; 1608 1609 /* If the remaining range is past end of file, we're done */ 1610 if ((off >> blkshift) > dn->dn_maxblkid) 1611 goto out; 1612 1613 ASSERT(ISP2(blksz)); 1614 if (trunc) 1615 tail = 0; 1616 else 1617 tail = P2PHASE(len, blksz); 1618 1619 ASSERT0(P2PHASE(off, blksz)); 1620 /* zero out any partial block data at the end of the range */ 1621 if (tail) { 1622 if (len < tail) 1623 tail = len; 1624 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off+len), 1625 TRUE, FALSE, FTAG, &db) == 0) { 1626 /* don't dirty if not on disk and not dirty */ 1627 if (db->db_last_dirty || 1628 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1629 rw_exit(&dn->dn_struct_rwlock); 1630 dmu_buf_will_dirty(&db->db, tx); 1631 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1632 bzero(db->db.db_data, tail); 1633 } 1634 dbuf_rele(db, FTAG); 1635 } 1636 len -= tail; 1637 } 1638 1639 /* If the range did not include a full block, we are done */ 1640 if (len == 0) 1641 goto out; 1642 1643 ASSERT(IS_P2ALIGNED(off, blksz)); 1644 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1645 blkid = off >> blkshift; 1646 nblks = len >> blkshift; 1647 if (trunc) 1648 nblks += 1; 1649 1650 /* 1651 * Dirty all the indirect blocks in this range. Note that only 1652 * the first and last indirect blocks can actually be written 1653 * (if they were partially freed) -- they must be dirtied, even if 1654 * they do not exist on disk yet. The interior blocks will 1655 * be freed by free_children(), so they will not actually be written. 1656 * Even though these interior blocks will not be written, we 1657 * dirty them for two reasons: 1658 * 1659 * - It ensures that the indirect blocks remain in memory until 1660 * syncing context. (They have already been prefetched by 1661 * dmu_tx_hold_free(), so we don't have to worry about reading 1662 * them serially here.) 1663 * 1664 * - The dirty space accounting will put pressure on the txg sync 1665 * mechanism to begin syncing, and to delay transactions if there 1666 * is a large amount of freeing. Even though these indirect 1667 * blocks will not be written, we could need to write the same 1668 * amount of space if we copy the freed BPs into deadlists. 1669 */ 1670 if (dn->dn_nlevels > 1) { 1671 uint64_t first, last; 1672 1673 first = blkid >> epbs; 1674 dnode_dirty_l1(dn, first, tx); 1675 if (trunc) 1676 last = dn->dn_maxblkid >> epbs; 1677 else 1678 last = (blkid + nblks - 1) >> epbs; 1679 if (last != first) 1680 dnode_dirty_l1(dn, last, tx); 1681 1682 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 1683 SPA_BLKPTRSHIFT; 1684 for (uint64_t i = first + 1; i < last; i++) { 1685 /* 1686 * Set i to the blockid of the next non-hole 1687 * level-1 indirect block at or after i. Note 1688 * that dnode_next_offset() operates in terms of 1689 * level-0-equivalent bytes. 1690 */ 1691 uint64_t ibyte = i << shift; 1692 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, 1693 &ibyte, 2, 1, 0); 1694 i = ibyte >> shift; 1695 if (i >= last) 1696 break; 1697 1698 /* 1699 * Normally we should not see an error, either 1700 * from dnode_next_offset() or dbuf_hold_level() 1701 * (except for ESRCH from dnode_next_offset). 1702 * If there is an i/o error, then when we read 1703 * this block in syncing context, it will use 1704 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according 1705 * to the "failmode" property. dnode_next_offset() 1706 * doesn't have a flag to indicate MUSTSUCCEED. 1707 */ 1708 if (err != 0) 1709 break; 1710 1711 dnode_dirty_l1(dn, i, tx); 1712 } 1713 } 1714 1715 done: 1716 /* 1717 * Add this range to the dnode range list. 1718 * We will finish up this free operation in the syncing phase. 1719 */ 1720 mutex_enter(&dn->dn_mtx); 1721 int txgoff = tx->tx_txg & TXG_MASK; 1722 if (dn->dn_free_ranges[txgoff] == NULL) { 1723 dn->dn_free_ranges[txgoff] = 1724 range_tree_create(NULL, NULL, &dn->dn_mtx); 1725 } 1726 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 1727 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 1728 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1729 blkid, nblks, tx->tx_txg); 1730 mutex_exit(&dn->dn_mtx); 1731 1732 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1733 dnode_setdirty(dn, tx); 1734 out: 1735 1736 rw_exit(&dn->dn_struct_rwlock); 1737 } 1738 1739 static boolean_t 1740 dnode_spill_freed(dnode_t *dn) 1741 { 1742 int i; 1743 1744 mutex_enter(&dn->dn_mtx); 1745 for (i = 0; i < TXG_SIZE; i++) { 1746 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1747 break; 1748 } 1749 mutex_exit(&dn->dn_mtx); 1750 return (i < TXG_SIZE); 1751 } 1752 1753 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1754 uint64_t 1755 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1756 { 1757 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1758 int i; 1759 1760 if (blkid == DMU_BONUS_BLKID) 1761 return (FALSE); 1762 1763 /* 1764 * If we're in the process of opening the pool, dp will not be 1765 * set yet, but there shouldn't be anything dirty. 1766 */ 1767 if (dp == NULL) 1768 return (FALSE); 1769 1770 if (dn->dn_free_txg) 1771 return (TRUE); 1772 1773 if (blkid == DMU_SPILL_BLKID) 1774 return (dnode_spill_freed(dn)); 1775 1776 mutex_enter(&dn->dn_mtx); 1777 for (i = 0; i < TXG_SIZE; i++) { 1778 if (dn->dn_free_ranges[i] != NULL && 1779 range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 1780 break; 1781 } 1782 mutex_exit(&dn->dn_mtx); 1783 return (i < TXG_SIZE); 1784 } 1785 1786 /* call from syncing context when we actually write/free space for this dnode */ 1787 void 1788 dnode_diduse_space(dnode_t *dn, int64_t delta) 1789 { 1790 uint64_t space; 1791 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1792 dn, dn->dn_phys, 1793 (u_longlong_t)dn->dn_phys->dn_used, 1794 (longlong_t)delta); 1795 1796 mutex_enter(&dn->dn_mtx); 1797 space = DN_USED_BYTES(dn->dn_phys); 1798 if (delta > 0) { 1799 ASSERT3U(space + delta, >=, space); /* no overflow */ 1800 } else { 1801 ASSERT3U(space, >=, -delta); /* no underflow */ 1802 } 1803 space += delta; 1804 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1805 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1806 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 1807 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1808 } else { 1809 dn->dn_phys->dn_used = space; 1810 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1811 } 1812 mutex_exit(&dn->dn_mtx); 1813 } 1814 1815 /* 1816 * Call when we think we're going to write/free space in open context to track 1817 * the amount of memory in use by the currently open txg. 1818 */ 1819 void 1820 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1821 { 1822 objset_t *os = dn->dn_objset; 1823 dsl_dataset_t *ds = os->os_dsl_dataset; 1824 int64_t aspace = spa_get_asize(os->os_spa, space); 1825 1826 if (ds != NULL) { 1827 dsl_dir_willuse_space(ds->ds_dir, aspace, tx); 1828 dsl_pool_dirty_space(dmu_tx_pool(tx), space, tx); 1829 } 1830 1831 dmu_tx_willuse_space(tx, aspace); 1832 } 1833 1834 /* 1835 * Scans a block at the indicated "level" looking for a hole or data, 1836 * depending on 'flags'. 1837 * 1838 * If level > 0, then we are scanning an indirect block looking at its 1839 * pointers. If level == 0, then we are looking at a block of dnodes. 1840 * 1841 * If we don't find what we are looking for in the block, we return ESRCH. 1842 * Otherwise, return with *offset pointing to the beginning (if searching 1843 * forwards) or end (if searching backwards) of the range covered by the 1844 * block pointer we matched on (or dnode). 1845 * 1846 * The basic search algorithm used below by dnode_next_offset() is to 1847 * use this function to search up the block tree (widen the search) until 1848 * we find something (i.e., we don't return ESRCH) and then search back 1849 * down the tree (narrow the search) until we reach our original search 1850 * level. 1851 */ 1852 static int 1853 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1854 int lvl, uint64_t blkfill, uint64_t txg) 1855 { 1856 dmu_buf_impl_t *db = NULL; 1857 void *data = NULL; 1858 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1859 uint64_t epb = 1ULL << epbs; 1860 uint64_t minfill, maxfill; 1861 boolean_t hole; 1862 int i, inc, error, span; 1863 1864 dprintf("probing object %llu offset %llx level %d of %u\n", 1865 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1866 1867 hole = ((flags & DNODE_FIND_HOLE) != 0); 1868 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1869 ASSERT(txg == 0 || !hole); 1870 1871 if (lvl == dn->dn_phys->dn_nlevels) { 1872 error = 0; 1873 epb = dn->dn_phys->dn_nblkptr; 1874 data = dn->dn_phys->dn_blkptr; 1875 } else { 1876 uint64_t blkid = dbuf_whichblock(dn, lvl, *offset); 1877 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FALSE, FTAG, &db); 1878 if (error) { 1879 if (error != ENOENT) 1880 return (error); 1881 if (hole) 1882 return (0); 1883 /* 1884 * This can only happen when we are searching up 1885 * the block tree for data. We don't really need to 1886 * adjust the offset, as we will just end up looking 1887 * at the pointer to this block in its parent, and its 1888 * going to be unallocated, so we will skip over it. 1889 */ 1890 return (SET_ERROR(ESRCH)); 1891 } 1892 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1893 if (error) { 1894 dbuf_rele(db, FTAG); 1895 return (error); 1896 } 1897 data = db->db.db_data; 1898 } 1899 1900 1901 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 1902 db->db_blkptr->blk_birth <= txg || 1903 BP_IS_HOLE(db->db_blkptr))) { 1904 /* 1905 * This can only happen when we are searching up the tree 1906 * and these conditions mean that we need to keep climbing. 1907 */ 1908 error = SET_ERROR(ESRCH); 1909 } else if (lvl == 0) { 1910 dnode_phys_t *dnp = data; 1911 span = DNODE_SHIFT; 1912 ASSERT(dn->dn_type == DMU_OT_DNODE); 1913 1914 for (i = (*offset >> span) & (blkfill - 1); 1915 i >= 0 && i < blkfill; i += inc) { 1916 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1917 break; 1918 *offset += (1ULL << span) * inc; 1919 } 1920 if (i < 0 || i == blkfill) 1921 error = SET_ERROR(ESRCH); 1922 } else { 1923 blkptr_t *bp = data; 1924 uint64_t start = *offset; 1925 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1926 minfill = 0; 1927 maxfill = blkfill << ((lvl - 1) * epbs); 1928 1929 if (hole) 1930 maxfill--; 1931 else 1932 minfill++; 1933 1934 *offset = *offset >> span; 1935 for (i = BF64_GET(*offset, 0, epbs); 1936 i >= 0 && i < epb; i += inc) { 1937 if (BP_GET_FILL(&bp[i]) >= minfill && 1938 BP_GET_FILL(&bp[i]) <= maxfill && 1939 (hole || bp[i].blk_birth > txg)) 1940 break; 1941 if (inc > 0 || *offset > 0) 1942 *offset += inc; 1943 } 1944 *offset = *offset << span; 1945 if (inc < 0) { 1946 /* traversing backwards; position offset at the end */ 1947 ASSERT3U(*offset, <=, start); 1948 *offset = MIN(*offset + (1ULL << span) - 1, start); 1949 } else if (*offset < start) { 1950 *offset = start; 1951 } 1952 if (i < 0 || i >= epb) 1953 error = SET_ERROR(ESRCH); 1954 } 1955 1956 if (db) 1957 dbuf_rele(db, FTAG); 1958 1959 return (error); 1960 } 1961 1962 /* 1963 * Find the next hole, data, or sparse region at or after *offset. 1964 * The value 'blkfill' tells us how many items we expect to find 1965 * in an L0 data block; this value is 1 for normal objects, 1966 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1967 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1968 * 1969 * Examples: 1970 * 1971 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1972 * Finds the next/previous hole/data in a file. 1973 * Used in dmu_offset_next(). 1974 * 1975 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1976 * Finds the next free/allocated dnode an objset's meta-dnode. 1977 * Only finds objects that have new contents since txg (ie. 1978 * bonus buffer changes and content removal are ignored). 1979 * Used in dmu_object_next(). 1980 * 1981 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1982 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1983 * Used in dmu_object_alloc(). 1984 */ 1985 int 1986 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1987 int minlvl, uint64_t blkfill, uint64_t txg) 1988 { 1989 uint64_t initial_offset = *offset; 1990 int lvl, maxlvl; 1991 int error = 0; 1992 1993 if (!(flags & DNODE_FIND_HAVELOCK)) 1994 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1995 1996 if (dn->dn_phys->dn_nlevels == 0) { 1997 error = SET_ERROR(ESRCH); 1998 goto out; 1999 } 2000 2001 if (dn->dn_datablkshift == 0) { 2002 if (*offset < dn->dn_datablksz) { 2003 if (flags & DNODE_FIND_HOLE) 2004 *offset = dn->dn_datablksz; 2005 } else { 2006 error = SET_ERROR(ESRCH); 2007 } 2008 goto out; 2009 } 2010 2011 maxlvl = dn->dn_phys->dn_nlevels; 2012 2013 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 2014 error = dnode_next_offset_level(dn, 2015 flags, offset, lvl, blkfill, txg); 2016 if (error != ESRCH) 2017 break; 2018 } 2019 2020 while (error == 0 && --lvl >= minlvl) { 2021 error = dnode_next_offset_level(dn, 2022 flags, offset, lvl, blkfill, txg); 2023 } 2024 2025 /* 2026 * There's always a "virtual hole" at the end of the object, even 2027 * if all BP's which physically exist are non-holes. 2028 */ 2029 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 && 2030 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) { 2031 error = 0; 2032 } 2033 2034 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 2035 initial_offset < *offset : initial_offset > *offset)) 2036 error = SET_ERROR(ESRCH); 2037 out: 2038 if (!(flags & DNODE_FIND_HAVELOCK)) 2039 rw_exit(&dn->dn_struct_rwlock); 2040 2041 return (error); 2042 } 2043
Indexes created Tue May 26 00:24:38 UTC 2026