dnode.c revision 288541
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, 2015 by Delphix. All rights reserved. 24 */ 25 26#include <sys/zfs_context.h> 27#include <sys/dbuf.h> 28#include <sys/dnode.h> 29#include <sys/dmu.h> 30#include <sys/dmu_impl.h> 31#include <sys/dmu_tx.h> 32#include <sys/dmu_objset.h> 33#include <sys/dsl_dir.h> 34#include <sys/dsl_dataset.h> 35#include <sys/spa.h> 36#include <sys/zio.h> 37#include <sys/dmu_zfetch.h> 38#include <sys/range_tree.h> 39 40static kmem_cache_t *dnode_cache; 41/* 42 * Define DNODE_STATS to turn on statistic gathering. By default, it is only 43 * turned on when DEBUG is also defined. 44 */ 45#ifdef DEBUG 46#define DNODE_STATS 47#endif /* DEBUG */ 48 49#ifdef DNODE_STATS 50#define DNODE_STAT_ADD(stat) ((stat)++) 51#else 52#define DNODE_STAT_ADD(stat) /* nothing */ 53#endif /* DNODE_STATS */ 54 55static dnode_phys_t dnode_phys_zero; 56 57int zfs_default_bs = SPA_MINBLOCKSHIFT; 58int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 59 60#ifdef sun 61static kmem_cbrc_t dnode_move(void *, void *, size_t, void *); 62#endif 63 64static int 65dbuf_compare(const void *x1, const void *x2) 66{ 67 const dmu_buf_impl_t *d1 = x1; 68 const dmu_buf_impl_t *d2 = x2; 69 70 if (d1->db_level < d2->db_level) { 71 return (-1); 72 } 73 if (d1->db_level > d2->db_level) { 74 return (1); 75 } 76 77 if (d1->db_blkid < d2->db_blkid) { 78 return (-1); 79 } 80 if (d1->db_blkid > d2->db_blkid) { 81 return (1); 82 } 83 84 if (d1->db_state == DB_SEARCH) { 85 ASSERT3S(d2->db_state, !=, DB_SEARCH); 86 return (-1); 87 } else if (d2->db_state == DB_SEARCH) { 88 ASSERT3S(d1->db_state, !=, DB_SEARCH); 89 return (1); 90 } 91 92 if ((uintptr_t)d1 < (uintptr_t)d2) { 93 return (-1); 94 } 95 if ((uintptr_t)d1 > (uintptr_t)d2) { 96 return (1); 97 } 98 return (0); 99} 100 101/* ARGSUSED */ 102static int 103dnode_cons(void *arg, void *unused, int kmflag) 104{ 105 dnode_t *dn = arg; 106 int i; 107 108 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 109 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 110 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 111 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 112 113 /* 114 * Every dbuf has a reference, and dropping a tracked reference is 115 * O(number of references), so don't track dn_holds. 116 */ 117 refcount_create_untracked(&dn->dn_holds); 118 refcount_create(&dn->dn_tx_holds); 119 list_link_init(&dn->dn_link); 120 121 bzero(&dn->dn_next_nblkptr[0], sizeof (dn->dn_next_nblkptr)); 122 bzero(&dn->dn_next_nlevels[0], sizeof (dn->dn_next_nlevels)); 123 bzero(&dn->dn_next_indblkshift[0], sizeof (dn->dn_next_indblkshift)); 124 bzero(&dn->dn_next_bonustype[0], sizeof (dn->dn_next_bonustype)); 125 bzero(&dn->dn_rm_spillblk[0], sizeof (dn->dn_rm_spillblk)); 126 bzero(&dn->dn_next_bonuslen[0], sizeof (dn->dn_next_bonuslen)); 127 bzero(&dn->dn_next_blksz[0], sizeof (dn->dn_next_blksz)); 128 129 for (i = 0; i < TXG_SIZE; i++) { 130 list_link_init(&dn->dn_dirty_link[i]); 131 dn->dn_free_ranges[i] = NULL; 132 list_create(&dn->dn_dirty_records[i], 133 sizeof (dbuf_dirty_record_t), 134 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 135 } 136 137 dn->dn_allocated_txg = 0; 138 dn->dn_free_txg = 0; 139 dn->dn_assigned_txg = 0; 140 dn->dn_dirtyctx = 0; 141 dn->dn_dirtyctx_firstset = NULL; 142 dn->dn_bonus = NULL; 143 dn->dn_have_spill = B_FALSE; 144 dn->dn_zio = NULL; 145 dn->dn_oldused = 0; 146 dn->dn_oldflags = 0; 147 dn->dn_olduid = 0; 148 dn->dn_oldgid = 0; 149 dn->dn_newuid = 0; 150 dn->dn_newgid = 0; 151 dn->dn_id_flags = 0; 152 153 dn->dn_dbufs_count = 0; 154 dn->dn_unlisted_l0_blkid = 0; 155 avl_create(&dn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 156 offsetof(dmu_buf_impl_t, db_link)); 157 158 dn->dn_moved = 0; 159 POINTER_INVALIDATE(&dn->dn_objset); 160 return (0); 161} 162 163/* ARGSUSED */ 164static void 165dnode_dest(void *arg, void *unused) 166{ 167 int i; 168 dnode_t *dn = arg; 169 170 rw_destroy(&dn->dn_struct_rwlock); 171 mutex_destroy(&dn->dn_mtx); 172 mutex_destroy(&dn->dn_dbufs_mtx); 173 cv_destroy(&dn->dn_notxholds); 174 refcount_destroy(&dn->dn_holds); 175 refcount_destroy(&dn->dn_tx_holds); 176 ASSERT(!list_link_active(&dn->dn_link)); 177 178 for (i = 0; i < TXG_SIZE; i++) { 179 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 180 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 181 list_destroy(&dn->dn_dirty_records[i]); 182 ASSERT0(dn->dn_next_nblkptr[i]); 183 ASSERT0(dn->dn_next_nlevels[i]); 184 ASSERT0(dn->dn_next_indblkshift[i]); 185 ASSERT0(dn->dn_next_bonustype[i]); 186 ASSERT0(dn->dn_rm_spillblk[i]); 187 ASSERT0(dn->dn_next_bonuslen[i]); 188 ASSERT0(dn->dn_next_blksz[i]); 189 } 190 191 ASSERT0(dn->dn_allocated_txg); 192 ASSERT0(dn->dn_free_txg); 193 ASSERT0(dn->dn_assigned_txg); 194 ASSERT0(dn->dn_dirtyctx); 195 ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL); 196 ASSERT3P(dn->dn_bonus, ==, NULL); 197 ASSERT(!dn->dn_have_spill); 198 ASSERT3P(dn->dn_zio, ==, NULL); 199 ASSERT0(dn->dn_oldused); 200 ASSERT0(dn->dn_oldflags); 201 ASSERT0(dn->dn_olduid); 202 ASSERT0(dn->dn_oldgid); 203 ASSERT0(dn->dn_newuid); 204 ASSERT0(dn->dn_newgid); 205 ASSERT0(dn->dn_id_flags); 206 207 ASSERT0(dn->dn_dbufs_count); 208 ASSERT0(dn->dn_unlisted_l0_blkid); 209 avl_destroy(&dn->dn_dbufs); 210} 211 212void 213dnode_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 222void 223dnode_fini(void) 224{ 225 kmem_cache_destroy(dnode_cache); 226 dnode_cache = NULL; 227} 228 229 230#ifdef ZFS_DEBUG 231void 232dnode_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 285void 286dnode_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 337void 338dnode_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 353void 354dnode_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 370void 371dnode_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 381void 382dnode_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 391static void 392dnode_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 404static dnode_t * 405dnode_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 = kmem_cache_alloc(dnode_cache, KM_SLEEP); 409 410 ASSERT(!POINTER_IS_VALID(dn->dn_objset)); 411 dn->dn_moved = 0; 412 413 /* 414 * Defer setting dn_objset until the dnode is ready to be a candidate 415 * for the dnode_move() callback. 416 */ 417 dn->dn_object = object; 418 dn->dn_dbuf = db; 419 dn->dn_handle = dnh; 420 dn->dn_phys = dnp; 421 422 if (dnp->dn_datablkszsec) { 423 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 424 } else { 425 dn->dn_datablksz = 0; 426 dn->dn_datablkszsec = 0; 427 dn->dn_datablkshift = 0; 428 } 429 dn->dn_indblkshift = dnp->dn_indblkshift; 430 dn->dn_nlevels = dnp->dn_nlevels; 431 dn->dn_type = dnp->dn_type; 432 dn->dn_nblkptr = dnp->dn_nblkptr; 433 dn->dn_checksum = dnp->dn_checksum; 434 dn->dn_compress = dnp->dn_compress; 435 dn->dn_bonustype = dnp->dn_bonustype; 436 dn->dn_bonuslen = dnp->dn_bonuslen; 437 dn->dn_maxblkid = dnp->dn_maxblkid; 438 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 439 dn->dn_id_flags = 0; 440 441 dmu_zfetch_init(&dn->dn_zfetch, dn); 442 443 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 444 445 mutex_enter(&os->os_lock); 446 list_insert_head(&os->os_dnodes, dn); 447 membar_producer(); 448 /* 449 * Everything else must be valid before assigning dn_objset makes the 450 * dnode eligible for dnode_move(). 451 */ 452 dn->dn_objset = os; 453 mutex_exit(&os->os_lock); 454 455 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 456 return (dn); 457} 458 459/* 460 * Caller must be holding the dnode handle, which is released upon return. 461 */ 462static void 463dnode_destroy(dnode_t *dn) 464{ 465 objset_t *os = dn->dn_objset; 466 467 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 468 469 mutex_enter(&os->os_lock); 470 POINTER_INVALIDATE(&dn->dn_objset); 471 list_remove(&os->os_dnodes, dn); 472 mutex_exit(&os->os_lock); 473 474 /* the dnode can no longer move, so we can release the handle */ 475 zrl_remove(&dn->dn_handle->dnh_zrlock); 476 477 dn->dn_allocated_txg = 0; 478 dn->dn_free_txg = 0; 479 dn->dn_assigned_txg = 0; 480 481 dn->dn_dirtyctx = 0; 482 if (dn->dn_dirtyctx_firstset != NULL) { 483 kmem_free(dn->dn_dirtyctx_firstset, 1); 484 dn->dn_dirtyctx_firstset = NULL; 485 } 486 if (dn->dn_bonus != NULL) { 487 mutex_enter(&dn->dn_bonus->db_mtx); 488 dbuf_evict(dn->dn_bonus); 489 dn->dn_bonus = NULL; 490 } 491 dn->dn_zio = NULL; 492 493 dn->dn_have_spill = B_FALSE; 494 dn->dn_oldused = 0; 495 dn->dn_oldflags = 0; 496 dn->dn_olduid = 0; 497 dn->dn_oldgid = 0; 498 dn->dn_newuid = 0; 499 dn->dn_newgid = 0; 500 dn->dn_id_flags = 0; 501 dn->dn_unlisted_l0_blkid = 0; 502 503 dmu_zfetch_rele(&dn->dn_zfetch); 504 kmem_cache_free(dnode_cache, dn); 505 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 506} 507 508void 509dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 510 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 511{ 512 int i; 513 514 ASSERT3U(blocksize, <=, 515 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 516 if (blocksize == 0) 517 blocksize = 1 << zfs_default_bs; 518 else 519 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 520 521 if (ibs == 0) 522 ibs = zfs_default_ibs; 523 524 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 525 526 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 527 dn->dn_object, tx->tx_txg, blocksize, ibs); 528 529 ASSERT(dn->dn_type == DMU_OT_NONE); 530 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 531 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 532 ASSERT(ot != DMU_OT_NONE); 533 ASSERT(DMU_OT_IS_VALID(ot)); 534 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 535 (bonustype == DMU_OT_SA && bonuslen == 0) || 536 (bonustype != DMU_OT_NONE && bonuslen != 0)); 537 ASSERT(DMU_OT_IS_VALID(bonustype)); 538 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 539 ASSERT(dn->dn_type == DMU_OT_NONE); 540 ASSERT0(dn->dn_maxblkid); 541 ASSERT0(dn->dn_allocated_txg); 542 ASSERT0(dn->dn_assigned_txg); 543 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 544 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 545 ASSERT(avl_is_empty(&dn->dn_dbufs)); 546 547 for (i = 0; i < TXG_SIZE; i++) { 548 ASSERT0(dn->dn_next_nblkptr[i]); 549 ASSERT0(dn->dn_next_nlevels[i]); 550 ASSERT0(dn->dn_next_indblkshift[i]); 551 ASSERT0(dn->dn_next_bonuslen[i]); 552 ASSERT0(dn->dn_next_bonustype[i]); 553 ASSERT0(dn->dn_rm_spillblk[i]); 554 ASSERT0(dn->dn_next_blksz[i]); 555 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 556 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 557 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 558 } 559 560 dn->dn_type = ot; 561 dnode_setdblksz(dn, blocksize); 562 dn->dn_indblkshift = ibs; 563 dn->dn_nlevels = 1; 564 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 565 dn->dn_nblkptr = 1; 566 else 567 dn->dn_nblkptr = 1 + 568 ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 569 dn->dn_bonustype = bonustype; 570 dn->dn_bonuslen = bonuslen; 571 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 572 dn->dn_compress = ZIO_COMPRESS_INHERIT; 573 dn->dn_dirtyctx = 0; 574 575 dn->dn_free_txg = 0; 576 if (dn->dn_dirtyctx_firstset) { 577 kmem_free(dn->dn_dirtyctx_firstset, 1); 578 dn->dn_dirtyctx_firstset = NULL; 579 } 580 581 dn->dn_allocated_txg = tx->tx_txg; 582 dn->dn_id_flags = 0; 583 584 dnode_setdirty(dn, tx); 585 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 586 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 587 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 588 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 589} 590 591void 592dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 593 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 594{ 595 int nblkptr; 596 597 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 598 ASSERT3U(blocksize, <=, 599 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 600 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 601 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 602 ASSERT(tx->tx_txg != 0); 603 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 604 (bonustype != DMU_OT_NONE && bonuslen != 0) || 605 (bonustype == DMU_OT_SA && bonuslen == 0)); 606 ASSERT(DMU_OT_IS_VALID(bonustype)); 607 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 608 609 /* clean up any unreferenced dbufs */ 610 dnode_evict_dbufs(dn); 611 612 dn->dn_id_flags = 0; 613 614 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 615 dnode_setdirty(dn, tx); 616 if (dn->dn_datablksz != blocksize) { 617 /* change blocksize */ 618 ASSERT(dn->dn_maxblkid == 0 && 619 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 620 dnode_block_freed(dn, 0))); 621 dnode_setdblksz(dn, blocksize); 622 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 623 } 624 if (dn->dn_bonuslen != bonuslen) 625 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 626 627 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 628 nblkptr = 1; 629 else 630 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 631 if (dn->dn_bonustype != bonustype) 632 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 633 if (dn->dn_nblkptr != nblkptr) 634 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 635 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 636 dbuf_rm_spill(dn, tx); 637 dnode_rm_spill(dn, tx); 638 } 639 rw_exit(&dn->dn_struct_rwlock); 640 641 /* change type */ 642 dn->dn_type = ot; 643 644 /* change bonus size and type */ 645 mutex_enter(&dn->dn_mtx); 646 dn->dn_bonustype = bonustype; 647 dn->dn_bonuslen = bonuslen; 648 dn->dn_nblkptr = nblkptr; 649 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 650 dn->dn_compress = ZIO_COMPRESS_INHERIT; 651 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 652 653 /* fix up the bonus db_size */ 654 if (dn->dn_bonus) { 655 dn->dn_bonus->db.db_size = 656 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 657 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 658 } 659 660 dn->dn_allocated_txg = tx->tx_txg; 661 mutex_exit(&dn->dn_mtx); 662} 663 664#ifdef DNODE_STATS 665static struct { 666 uint64_t dms_dnode_invalid; 667 uint64_t dms_dnode_recheck1; 668 uint64_t dms_dnode_recheck2; 669 uint64_t dms_dnode_special; 670 uint64_t dms_dnode_handle; 671 uint64_t dms_dnode_rwlock; 672 uint64_t dms_dnode_active; 673} dnode_move_stats; 674#endif /* DNODE_STATS */ 675 676static void 677dnode_move_impl(dnode_t *odn, dnode_t *ndn) 678{ 679 int i; 680 681 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 682 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 683 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 684 ASSERT(!RW_LOCK_HELD(&odn->dn_zfetch.zf_rwlock)); 685 686 /* Copy fields. */ 687 ndn->dn_objset = odn->dn_objset; 688 ndn->dn_object = odn->dn_object; 689 ndn->dn_dbuf = odn->dn_dbuf; 690 ndn->dn_handle = odn->dn_handle; 691 ndn->dn_phys = odn->dn_phys; 692 ndn->dn_type = odn->dn_type; 693 ndn->dn_bonuslen = odn->dn_bonuslen; 694 ndn->dn_bonustype = odn->dn_bonustype; 695 ndn->dn_nblkptr = odn->dn_nblkptr; 696 ndn->dn_checksum = odn->dn_checksum; 697 ndn->dn_compress = odn->dn_compress; 698 ndn->dn_nlevels = odn->dn_nlevels; 699 ndn->dn_indblkshift = odn->dn_indblkshift; 700 ndn->dn_datablkshift = odn->dn_datablkshift; 701 ndn->dn_datablkszsec = odn->dn_datablkszsec; 702 ndn->dn_datablksz = odn->dn_datablksz; 703 ndn->dn_maxblkid = odn->dn_maxblkid; 704 bcopy(&odn->dn_next_nblkptr[0], &ndn->dn_next_nblkptr[0], 705 sizeof (odn->dn_next_nblkptr)); 706 bcopy(&odn->dn_next_nlevels[0], &ndn->dn_next_nlevels[0], 707 sizeof (odn->dn_next_nlevels)); 708 bcopy(&odn->dn_next_indblkshift[0], &ndn->dn_next_indblkshift[0], 709 sizeof (odn->dn_next_indblkshift)); 710 bcopy(&odn->dn_next_bonustype[0], &ndn->dn_next_bonustype[0], 711 sizeof (odn->dn_next_bonustype)); 712 bcopy(&odn->dn_rm_spillblk[0], &ndn->dn_rm_spillblk[0], 713 sizeof (odn->dn_rm_spillblk)); 714 bcopy(&odn->dn_next_bonuslen[0], &ndn->dn_next_bonuslen[0], 715 sizeof (odn->dn_next_bonuslen)); 716 bcopy(&odn->dn_next_blksz[0], &ndn->dn_next_blksz[0], 717 sizeof (odn->dn_next_blksz)); 718 for (i = 0; i < TXG_SIZE; i++) { 719 list_move_tail(&ndn->dn_dirty_records[i], 720 &odn->dn_dirty_records[i]); 721 } 722 bcopy(&odn->dn_free_ranges[0], &ndn->dn_free_ranges[0], 723 sizeof (odn->dn_free_ranges)); 724 ndn->dn_allocated_txg = odn->dn_allocated_txg; 725 ndn->dn_free_txg = odn->dn_free_txg; 726 ndn->dn_assigned_txg = odn->dn_assigned_txg; 727 ndn->dn_dirtyctx = odn->dn_dirtyctx; 728 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 729 ASSERT(refcount_count(&odn->dn_tx_holds) == 0); 730 refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 731 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 732 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 733 ndn->dn_dbufs_count = odn->dn_dbufs_count; 734 ndn->dn_unlisted_l0_blkid = odn->dn_unlisted_l0_blkid; 735 ndn->dn_bonus = odn->dn_bonus; 736 ndn->dn_have_spill = odn->dn_have_spill; 737 ndn->dn_zio = odn->dn_zio; 738 ndn->dn_oldused = odn->dn_oldused; 739 ndn->dn_oldflags = odn->dn_oldflags; 740 ndn->dn_olduid = odn->dn_olduid; 741 ndn->dn_oldgid = odn->dn_oldgid; 742 ndn->dn_newuid = odn->dn_newuid; 743 ndn->dn_newgid = odn->dn_newgid; 744 ndn->dn_id_flags = odn->dn_id_flags; 745 dmu_zfetch_init(&ndn->dn_zfetch, NULL); 746 list_move_tail(&ndn->dn_zfetch.zf_stream, &odn->dn_zfetch.zf_stream); 747 ndn->dn_zfetch.zf_dnode = odn->dn_zfetch.zf_dnode; 748 ndn->dn_zfetch.zf_stream_cnt = odn->dn_zfetch.zf_stream_cnt; 749 ndn->dn_zfetch.zf_alloc_fail = odn->dn_zfetch.zf_alloc_fail; 750 751 /* 752 * Update back pointers. Updating the handle fixes the back pointer of 753 * every descendant dbuf as well as the bonus dbuf. 754 */ 755 ASSERT(ndn->dn_handle->dnh_dnode == odn); 756 ndn->dn_handle->dnh_dnode = ndn; 757 if (ndn->dn_zfetch.zf_dnode == odn) { 758 ndn->dn_zfetch.zf_dnode = ndn; 759 } 760 761 /* 762 * Invalidate the original dnode by clearing all of its back pointers. 763 */ 764 odn->dn_dbuf = NULL; 765 odn->dn_handle = NULL; 766 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 767 offsetof(dmu_buf_impl_t, db_link)); 768 odn->dn_dbufs_count = 0; 769 odn->dn_unlisted_l0_blkid = 0; 770 odn->dn_bonus = NULL; 771 odn->dn_zfetch.zf_dnode = NULL; 772 773 /* 774 * Set the low bit of the objset pointer to ensure that dnode_move() 775 * recognizes the dnode as invalid in any subsequent callback. 776 */ 777 POINTER_INVALIDATE(&odn->dn_objset); 778 779 /* 780 * Satisfy the destructor. 781 */ 782 for (i = 0; i < TXG_SIZE; i++) { 783 list_create(&odn->dn_dirty_records[i], 784 sizeof (dbuf_dirty_record_t), 785 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 786 odn->dn_free_ranges[i] = NULL; 787 odn->dn_next_nlevels[i] = 0; 788 odn->dn_next_indblkshift[i] = 0; 789 odn->dn_next_bonustype[i] = 0; 790 odn->dn_rm_spillblk[i] = 0; 791 odn->dn_next_bonuslen[i] = 0; 792 odn->dn_next_blksz[i] = 0; 793 } 794 odn->dn_allocated_txg = 0; 795 odn->dn_free_txg = 0; 796 odn->dn_assigned_txg = 0; 797 odn->dn_dirtyctx = 0; 798 odn->dn_dirtyctx_firstset = NULL; 799 odn->dn_have_spill = B_FALSE; 800 odn->dn_zio = NULL; 801 odn->dn_oldused = 0; 802 odn->dn_oldflags = 0; 803 odn->dn_olduid = 0; 804 odn->dn_oldgid = 0; 805 odn->dn_newuid = 0; 806 odn->dn_newgid = 0; 807 odn->dn_id_flags = 0; 808 809 /* 810 * Mark the dnode. 811 */ 812 ndn->dn_moved = 1; 813 odn->dn_moved = (uint8_t)-1; 814} 815 816#ifdef sun 817#ifdef _KERNEL 818/*ARGSUSED*/ 819static kmem_cbrc_t 820dnode_move(void *buf, void *newbuf, size_t size, void *arg) 821{ 822 dnode_t *odn = buf, *ndn = newbuf; 823 objset_t *os; 824 int64_t refcount; 825 uint32_t dbufs; 826 827 /* 828 * The dnode is on the objset's list of known dnodes if the objset 829 * pointer is valid. We set the low bit of the objset pointer when 830 * freeing the dnode to invalidate it, and the memory patterns written 831 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 832 * A newly created dnode sets the objset pointer last of all to indicate 833 * that the dnode is known and in a valid state to be moved by this 834 * function. 835 */ 836 os = odn->dn_objset; 837 if (!POINTER_IS_VALID(os)) { 838 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_invalid); 839 return (KMEM_CBRC_DONT_KNOW); 840 } 841 842 /* 843 * Ensure that the objset does not go away during the move. 844 */ 845 rw_enter(&os_lock, RW_WRITER); 846 if (os != odn->dn_objset) { 847 rw_exit(&os_lock); 848 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck1); 849 return (KMEM_CBRC_DONT_KNOW); 850 } 851 852 /* 853 * If the dnode is still valid, then so is the objset. We know that no 854 * valid objset can be freed while we hold os_lock, so we can safely 855 * ensure that the objset remains in use. 856 */ 857 mutex_enter(&os->os_lock); 858 859 /* 860 * Recheck the objset pointer in case the dnode was removed just before 861 * acquiring the lock. 862 */ 863 if (os != odn->dn_objset) { 864 mutex_exit(&os->os_lock); 865 rw_exit(&os_lock); 866 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck2); 867 return (KMEM_CBRC_DONT_KNOW); 868 } 869 870 /* 871 * At this point we know that as long as we hold os->os_lock, the dnode 872 * cannot be freed and fields within the dnode can be safely accessed. 873 * The objset listing this dnode cannot go away as long as this dnode is 874 * on its list. 875 */ 876 rw_exit(&os_lock); 877 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 878 mutex_exit(&os->os_lock); 879 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_special); 880 return (KMEM_CBRC_NO); 881 } 882 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 883 884 /* 885 * Lock the dnode handle to prevent the dnode from obtaining any new 886 * holds. This also prevents the descendant dbufs and the bonus dbuf 887 * from accessing the dnode, so that we can discount their holds. The 888 * handle is safe to access because we know that while the dnode cannot 889 * go away, neither can its handle. Once we hold dnh_zrlock, we can 890 * safely move any dnode referenced only by dbufs. 891 */ 892 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 893 mutex_exit(&os->os_lock); 894 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_handle); 895 return (KMEM_CBRC_LATER); 896 } 897 898 /* 899 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 900 * We need to guarantee that there is a hold for every dbuf in order to 901 * determine whether the dnode is actively referenced. Falsely matching 902 * a dbuf to an active hold would lead to an unsafe move. It's possible 903 * that a thread already having an active dnode hold is about to add a 904 * dbuf, and we can't compare hold and dbuf counts while the add is in 905 * progress. 906 */ 907 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 908 zrl_exit(&odn->dn_handle->dnh_zrlock); 909 mutex_exit(&os->os_lock); 910 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_rwlock); 911 return (KMEM_CBRC_LATER); 912 } 913 914 /* 915 * A dbuf may be removed (evicted) without an active dnode hold. In that 916 * case, the dbuf count is decremented under the handle lock before the 917 * dbuf's hold is released. This order ensures that if we count the hold 918 * after the dbuf is removed but before its hold is released, we will 919 * treat the unmatched hold as active and exit safely. If we count the 920 * hold before the dbuf is removed, the hold is discounted, and the 921 * removal is blocked until the move completes. 922 */ 923 refcount = refcount_count(&odn->dn_holds); 924 ASSERT(refcount >= 0); 925 dbufs = odn->dn_dbufs_count; 926 927 /* We can't have more dbufs than dnode holds. */ 928 ASSERT3U(dbufs, <=, refcount); 929 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 930 uint32_t, dbufs); 931 932 if (refcount > dbufs) { 933 rw_exit(&odn->dn_struct_rwlock); 934 zrl_exit(&odn->dn_handle->dnh_zrlock); 935 mutex_exit(&os->os_lock); 936 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_active); 937 return (KMEM_CBRC_LATER); 938 } 939 940 rw_exit(&odn->dn_struct_rwlock); 941 942 /* 943 * At this point we know that anyone with a hold on the dnode is not 944 * actively referencing it. The dnode is known and in a valid state to 945 * move. We're holding the locks needed to execute the critical section. 946 */ 947 dnode_move_impl(odn, ndn); 948 949 list_link_replace(&odn->dn_link, &ndn->dn_link); 950 /* If the dnode was safe to move, the refcount cannot have changed. */ 951 ASSERT(refcount == refcount_count(&ndn->dn_holds)); 952 ASSERT(dbufs == ndn->dn_dbufs_count); 953 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 954 mutex_exit(&os->os_lock); 955 956 return (KMEM_CBRC_YES); 957} 958#endif /* _KERNEL */ 959#endif /* sun */ 960 961void 962dnode_special_close(dnode_handle_t *dnh) 963{ 964 dnode_t *dn = dnh->dnh_dnode; 965 966 /* 967 * Wait for final references to the dnode to clear. This can 968 * only happen if the arc is asyncronously evicting state that 969 * has a hold on this dnode while we are trying to evict this 970 * dnode. 971 */ 972 while (refcount_count(&dn->dn_holds) > 0) 973 delay(1); 974 zrl_add(&dnh->dnh_zrlock); 975 dnode_destroy(dn); /* implicit zrl_remove() */ 976 zrl_destroy(&dnh->dnh_zrlock); 977 dnh->dnh_dnode = NULL; 978} 979 980dnode_t * 981dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 982 dnode_handle_t *dnh) 983{ 984 dnode_t *dn = dnode_create(os, dnp, NULL, object, dnh); 985 dnh->dnh_dnode = dn; 986 zrl_init(&dnh->dnh_zrlock); 987 DNODE_VERIFY(dn); 988 return (dn); 989} 990 991static void 992dnode_buf_pageout(dmu_buf_t *db, void *arg) 993{ 994 dnode_children_t *children_dnodes = arg; 995 int i; 996 int epb = db->db_size >> DNODE_SHIFT; 997 998 ASSERT(epb == children_dnodes->dnc_count); 999 1000 for (i = 0; i < epb; i++) { 1001 dnode_handle_t *dnh = &children_dnodes->dnc_children[i]; 1002 dnode_t *dn; 1003 1004 /* 1005 * The dnode handle lock guards against the dnode moving to 1006 * another valid address, so there is no need here to guard 1007 * against changes to or from NULL. 1008 */ 1009 if (dnh->dnh_dnode == NULL) { 1010 zrl_destroy(&dnh->dnh_zrlock); 1011 continue; 1012 } 1013 1014 zrl_add(&dnh->dnh_zrlock); 1015 dn = dnh->dnh_dnode; 1016 /* 1017 * If there are holds on this dnode, then there should 1018 * be holds on the dnode's containing dbuf as well; thus 1019 * it wouldn't be eligible for eviction and this function 1020 * would not have been called. 1021 */ 1022 ASSERT(refcount_is_zero(&dn->dn_holds)); 1023 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 1024 1025 dnode_destroy(dn); /* implicit zrl_remove() */ 1026 zrl_destroy(&dnh->dnh_zrlock); 1027 dnh->dnh_dnode = NULL; 1028 } 1029 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1030 epb * sizeof (dnode_handle_t)); 1031} 1032 1033/* 1034 * errors: 1035 * EINVAL - invalid object number. 1036 * EIO - i/o error. 1037 * succeeds even for free dnodes. 1038 */ 1039int 1040dnode_hold_impl(objset_t *os, uint64_t object, int flag, 1041 void *tag, dnode_t **dnp) 1042{ 1043 int epb, idx, err; 1044 int drop_struct_lock = FALSE; 1045 int type; 1046 uint64_t blk; 1047 dnode_t *mdn, *dn; 1048 dmu_buf_impl_t *db; 1049 dnode_children_t *children_dnodes; 1050 dnode_handle_t *dnh; 1051 1052 /* 1053 * If you are holding the spa config lock as writer, you shouldn't 1054 * be asking the DMU to do *anything* unless it's the root pool 1055 * which may require us to read from the root filesystem while 1056 * holding some (not all) of the locks as writer. 1057 */ 1058 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1059 (spa_is_root(os->os_spa) && 1060 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1061 1062 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 1063 dn = (object == DMU_USERUSED_OBJECT) ? 1064 DMU_USERUSED_DNODE(os) : DMU_GROUPUSED_DNODE(os); 1065 if (dn == NULL) 1066 return (SET_ERROR(ENOENT)); 1067 type = dn->dn_type; 1068 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1069 return (SET_ERROR(ENOENT)); 1070 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1071 return (SET_ERROR(EEXIST)); 1072 DNODE_VERIFY(dn); 1073 (void) refcount_add(&dn->dn_holds, tag); 1074 *dnp = dn; 1075 return (0); 1076 } 1077 1078 if (object == 0 || object >= DN_MAX_OBJECT) 1079 return (SET_ERROR(EINVAL)); 1080 1081 mdn = DMU_META_DNODE(os); 1082 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1083 1084 DNODE_VERIFY(mdn); 1085 1086 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1087 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1088 drop_struct_lock = TRUE; 1089 } 1090 1091 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 1092 1093 db = dbuf_hold(mdn, blk, FTAG); 1094 if (drop_struct_lock) 1095 rw_exit(&mdn->dn_struct_rwlock); 1096 if (db == NULL) 1097 return (SET_ERROR(EIO)); 1098 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 1099 if (err) { 1100 dbuf_rele(db, FTAG); 1101 return (err); 1102 } 1103 1104 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1105 epb = db->db.db_size >> DNODE_SHIFT; 1106 1107 idx = object & (epb-1); 1108 1109 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1110 children_dnodes = dmu_buf_get_user(&db->db); 1111 if (children_dnodes == NULL) { 1112 int i; 1113 dnode_children_t *winner; 1114 children_dnodes = kmem_zalloc(sizeof (dnode_children_t) + 1115 epb * sizeof (dnode_handle_t), KM_SLEEP); 1116 children_dnodes->dnc_count = epb; 1117 dnh = &children_dnodes->dnc_children[0]; 1118 for (i = 0; i < epb; i++) { 1119 zrl_init(&dnh[i].dnh_zrlock); 1120 dnh[i].dnh_dnode = NULL; 1121 } 1122 if (winner = dmu_buf_set_user(&db->db, children_dnodes, 1123 dnode_buf_pageout)) { 1124 1125 for (i = 0; i < epb; i++) { 1126 zrl_destroy(&dnh[i].dnh_zrlock); 1127 } 1128 1129 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1130 epb * sizeof (dnode_handle_t)); 1131 children_dnodes = winner; 1132 } 1133 } 1134 ASSERT(children_dnodes->dnc_count == epb); 1135 1136 dnh = &children_dnodes->dnc_children[idx]; 1137 zrl_add(&dnh->dnh_zrlock); 1138 if ((dn = dnh->dnh_dnode) == NULL) { 1139 dnode_phys_t *phys = (dnode_phys_t *)db->db.db_data+idx; 1140 dnode_t *winner; 1141 1142 dn = dnode_create(os, phys, db, object, dnh); 1143 winner = atomic_cas_ptr(&dnh->dnh_dnode, NULL, dn); 1144 if (winner != NULL) { 1145 zrl_add(&dnh->dnh_zrlock); 1146 dnode_destroy(dn); /* implicit zrl_remove() */ 1147 dn = winner; 1148 } 1149 } 1150 1151 mutex_enter(&dn->dn_mtx); 1152 type = dn->dn_type; 1153 if (dn->dn_free_txg || 1154 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 1155 ((flag & DNODE_MUST_BE_FREE) && 1156 (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) { 1157 mutex_exit(&dn->dn_mtx); 1158 zrl_remove(&dnh->dnh_zrlock); 1159 dbuf_rele(db, FTAG); 1160 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 1161 } 1162 mutex_exit(&dn->dn_mtx); 1163 1164 if (refcount_add(&dn->dn_holds, tag) == 1) 1165 dbuf_add_ref(db, dnh); 1166 /* Now we can rely on the hold to prevent the dnode from moving. */ 1167 zrl_remove(&dnh->dnh_zrlock); 1168 1169 DNODE_VERIFY(dn); 1170 ASSERT3P(dn->dn_dbuf, ==, db); 1171 ASSERT3U(dn->dn_object, ==, object); 1172 dbuf_rele(db, FTAG); 1173 1174 *dnp = dn; 1175 return (0); 1176} 1177 1178/* 1179 * Return held dnode if the object is allocated, NULL if not. 1180 */ 1181int 1182dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 1183{ 1184 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 1185} 1186 1187/* 1188 * Can only add a reference if there is already at least one 1189 * reference on the dnode. Returns FALSE if unable to add a 1190 * new reference. 1191 */ 1192boolean_t 1193dnode_add_ref(dnode_t *dn, void *tag) 1194{ 1195 mutex_enter(&dn->dn_mtx); 1196 if (refcount_is_zero(&dn->dn_holds)) { 1197 mutex_exit(&dn->dn_mtx); 1198 return (FALSE); 1199 } 1200 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 1201 mutex_exit(&dn->dn_mtx); 1202 return (TRUE); 1203} 1204 1205void 1206dnode_rele(dnode_t *dn, void *tag) 1207{ 1208 mutex_enter(&dn->dn_mtx); 1209 dnode_rele_and_unlock(dn, tag); 1210} 1211 1212void 1213dnode_rele_and_unlock(dnode_t *dn, void *tag) 1214{ 1215 uint64_t refs; 1216 /* Get while the hold prevents the dnode from moving. */ 1217 dmu_buf_impl_t *db = dn->dn_dbuf; 1218 dnode_handle_t *dnh = dn->dn_handle; 1219 1220 refs = refcount_remove(&dn->dn_holds, tag); 1221 mutex_exit(&dn->dn_mtx); 1222 1223 /* 1224 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1225 * indirectly by dbuf_rele() while relying on the dnode handle to 1226 * prevent the dnode from moving, since releasing the last hold could 1227 * result in the dnode's parent dbuf evicting its dnode handles. For 1228 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1229 * other direct or indirect hold on the dnode must first drop the dnode 1230 * handle. 1231 */ 1232 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread); 1233 1234 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1235 if (refs == 0 && db != NULL) { 1236 /* 1237 * Another thread could add a hold to the dnode handle in 1238 * dnode_hold_impl() while holding the parent dbuf. Since the 1239 * hold on the parent dbuf prevents the handle from being 1240 * destroyed, the hold on the handle is OK. We can't yet assert 1241 * that the handle has zero references, but that will be 1242 * asserted anyway when the handle gets destroyed. 1243 */ 1244 dbuf_rele(db, dnh); 1245 } 1246} 1247 1248void 1249dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1250{ 1251 objset_t *os = dn->dn_objset; 1252 uint64_t txg = tx->tx_txg; 1253 1254 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1255 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1256 return; 1257 } 1258 1259 DNODE_VERIFY(dn); 1260 1261#ifdef ZFS_DEBUG 1262 mutex_enter(&dn->dn_mtx); 1263 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1264 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1265 mutex_exit(&dn->dn_mtx); 1266#endif 1267 1268 /* 1269 * Determine old uid/gid when necessary 1270 */ 1271 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1272 1273 mutex_enter(&os->os_lock); 1274 1275 /* 1276 * If we are already marked dirty, we're done. 1277 */ 1278 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1279 mutex_exit(&os->os_lock); 1280 return; 1281 } 1282 1283 ASSERT(!refcount_is_zero(&dn->dn_holds) || 1284 !avl_is_empty(&dn->dn_dbufs)); 1285 ASSERT(dn->dn_datablksz != 0); 1286 ASSERT0(dn->dn_next_bonuslen[txg&TXG_MASK]); 1287 ASSERT0(dn->dn_next_blksz[txg&TXG_MASK]); 1288 ASSERT0(dn->dn_next_bonustype[txg&TXG_MASK]); 1289 1290 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1291 dn->dn_object, txg); 1292 1293 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 1294 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 1295 } else { 1296 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 1297 } 1298 1299 mutex_exit(&os->os_lock); 1300 1301 /* 1302 * The dnode maintains a hold on its containing dbuf as 1303 * long as there are holds on it. Each instantiated child 1304 * dbuf maintains a hold on the dnode. When the last child 1305 * drops its hold, the dnode will drop its hold on the 1306 * containing dbuf. We add a "dirty hold" here so that the 1307 * dnode will hang around after we finish processing its 1308 * children. 1309 */ 1310 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1311 1312 (void) dbuf_dirty(dn->dn_dbuf, tx); 1313 1314 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1315} 1316 1317void 1318dnode_free(dnode_t *dn, dmu_tx_t *tx) 1319{ 1320 int txgoff = tx->tx_txg & TXG_MASK; 1321 1322 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 1323 1324 /* we should be the only holder... hopefully */ 1325 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 1326 1327 mutex_enter(&dn->dn_mtx); 1328 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1329 mutex_exit(&dn->dn_mtx); 1330 return; 1331 } 1332 dn->dn_free_txg = tx->tx_txg; 1333 mutex_exit(&dn->dn_mtx); 1334 1335 /* 1336 * If the dnode is already dirty, it needs to be moved from 1337 * the dirty list to the free list. 1338 */ 1339 mutex_enter(&dn->dn_objset->os_lock); 1340 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 1341 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 1342 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 1343 mutex_exit(&dn->dn_objset->os_lock); 1344 } else { 1345 mutex_exit(&dn->dn_objset->os_lock); 1346 dnode_setdirty(dn, tx); 1347 } 1348} 1349 1350/* 1351 * Try to change the block size for the indicated dnode. This can only 1352 * succeed if there are no blocks allocated or dirty beyond first block 1353 */ 1354int 1355dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1356{ 1357 dmu_buf_impl_t *db; 1358 int err; 1359 1360 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 1361 if (size == 0) 1362 size = SPA_MINBLOCKSIZE; 1363 else 1364 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1365 1366 if (ibs == dn->dn_indblkshift) 1367 ibs = 0; 1368 1369 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 1370 return (0); 1371 1372 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1373 1374 /* Check for any allocated blocks beyond the first */ 1375 if (dn->dn_maxblkid != 0) 1376 goto fail; 1377 1378 mutex_enter(&dn->dn_dbufs_mtx); 1379 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1380 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1381 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1382 db->db_blkid != DMU_SPILL_BLKID) { 1383 mutex_exit(&dn->dn_dbufs_mtx); 1384 goto fail; 1385 } 1386 } 1387 mutex_exit(&dn->dn_dbufs_mtx); 1388 1389 if (ibs && dn->dn_nlevels != 1) 1390 goto fail; 1391 1392 /* resize the old block */ 1393 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 1394 if (err == 0) 1395 dbuf_new_size(db, size, tx); 1396 else if (err != ENOENT) 1397 goto fail; 1398 1399 dnode_setdblksz(dn, size); 1400 dnode_setdirty(dn, tx); 1401 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 1402 if (ibs) { 1403 dn->dn_indblkshift = ibs; 1404 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 1405 } 1406 /* rele after we have fixed the blocksize in the dnode */ 1407 if (db) 1408 dbuf_rele(db, FTAG); 1409 1410 rw_exit(&dn->dn_struct_rwlock); 1411 return (0); 1412 1413fail: 1414 rw_exit(&dn->dn_struct_rwlock); 1415 return (SET_ERROR(ENOTSUP)); 1416} 1417 1418/* read-holding callers must not rely on the lock being continuously held */ 1419void 1420dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 1421{ 1422 uint64_t txgoff = tx->tx_txg & TXG_MASK; 1423 int epbs, new_nlevels; 1424 uint64_t sz; 1425 1426 ASSERT(blkid != DMU_BONUS_BLKID); 1427 1428 ASSERT(have_read ? 1429 RW_READ_HELD(&dn->dn_struct_rwlock) : 1430 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 1431 1432 /* 1433 * if we have a read-lock, check to see if we need to do any work 1434 * before upgrading to a write-lock. 1435 */ 1436 if (have_read) { 1437 if (blkid <= dn->dn_maxblkid) 1438 return; 1439 1440 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 1441 rw_exit(&dn->dn_struct_rwlock); 1442 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1443 } 1444 } 1445 1446 if (blkid <= dn->dn_maxblkid) 1447 goto out; 1448 1449 dn->dn_maxblkid = blkid; 1450 1451 /* 1452 * Compute the number of levels necessary to support the new maxblkid. 1453 */ 1454 new_nlevels = 1; 1455 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1456 for (sz = dn->dn_nblkptr; 1457 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 1458 new_nlevels++; 1459 1460 if (new_nlevels > dn->dn_nlevels) { 1461 int old_nlevels = dn->dn_nlevels; 1462 dmu_buf_impl_t *db; 1463 list_t *list; 1464 dbuf_dirty_record_t *new, *dr, *dr_next; 1465 1466 dn->dn_nlevels = new_nlevels; 1467 1468 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 1469 dn->dn_next_nlevels[txgoff] = new_nlevels; 1470 1471 /* dirty the left indirects */ 1472 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 1473 ASSERT(db != NULL); 1474 new = dbuf_dirty(db, tx); 1475 dbuf_rele(db, FTAG); 1476 1477 /* transfer the dirty records to the new indirect */ 1478 mutex_enter(&dn->dn_mtx); 1479 mutex_enter(&new->dt.di.dr_mtx); 1480 list = &dn->dn_dirty_records[txgoff]; 1481 for (dr = list_head(list); dr; dr = dr_next) { 1482 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 1483 if (dr->dr_dbuf->db_level != new_nlevels-1 && 1484 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 1485 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 1486 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 1487 list_remove(&dn->dn_dirty_records[txgoff], dr); 1488 list_insert_tail(&new->dt.di.dr_children, dr); 1489 dr->dr_parent = new; 1490 } 1491 } 1492 mutex_exit(&new->dt.di.dr_mtx); 1493 mutex_exit(&dn->dn_mtx); 1494 } 1495 1496out: 1497 if (have_read) 1498 rw_downgrade(&dn->dn_struct_rwlock); 1499} 1500 1501static void 1502dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx) 1503{ 1504 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG); 1505 if (db != NULL) { 1506 dmu_buf_will_dirty(&db->db, tx); 1507 dbuf_rele(db, FTAG); 1508 } 1509} 1510 1511void 1512dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1513{ 1514 dmu_buf_impl_t *db; 1515 uint64_t blkoff, blkid, nblks; 1516 int blksz, blkshift, head, tail; 1517 int trunc = FALSE; 1518 int epbs; 1519 1520 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1521 blksz = dn->dn_datablksz; 1522 blkshift = dn->dn_datablkshift; 1523 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1524 1525 if (len == DMU_OBJECT_END) { 1526 len = UINT64_MAX - off; 1527 trunc = TRUE; 1528 } 1529 1530 /* 1531 * First, block align the region to free: 1532 */ 1533 if (ISP2(blksz)) { 1534 head = P2NPHASE(off, blksz); 1535 blkoff = P2PHASE(off, blksz); 1536 if ((off >> blkshift) > dn->dn_maxblkid) 1537 goto out; 1538 } else { 1539 ASSERT(dn->dn_maxblkid == 0); 1540 if (off == 0 && len >= blksz) { 1541 /* 1542 * Freeing the whole block; fast-track this request. 1543 * Note that we won't dirty any indirect blocks, 1544 * which is fine because we will be freeing the entire 1545 * file and thus all indirect blocks will be freed 1546 * by free_children(). 1547 */ 1548 blkid = 0; 1549 nblks = 1; 1550 goto done; 1551 } else if (off >= blksz) { 1552 /* Freeing past end-of-data */ 1553 goto out; 1554 } else { 1555 /* Freeing part of the block. */ 1556 head = blksz - off; 1557 ASSERT3U(head, >, 0); 1558 } 1559 blkoff = off; 1560 } 1561 /* zero out any partial block data at the start of the range */ 1562 if (head) { 1563 ASSERT3U(blkoff + head, ==, blksz); 1564 if (len < head) 1565 head = len; 1566 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1567 FTAG, &db) == 0) { 1568 caddr_t data; 1569 1570 /* don't dirty if it isn't on disk and isn't dirty */ 1571 if (db->db_last_dirty || 1572 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1573 rw_exit(&dn->dn_struct_rwlock); 1574 dmu_buf_will_dirty(&db->db, tx); 1575 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1576 data = db->db.db_data; 1577 bzero(data + blkoff, head); 1578 } 1579 dbuf_rele(db, FTAG); 1580 } 1581 off += head; 1582 len -= head; 1583 } 1584 1585 /* If the range was less than one block, we're done */ 1586 if (len == 0) 1587 goto out; 1588 1589 /* If the remaining range is past end of file, we're done */ 1590 if ((off >> blkshift) > dn->dn_maxblkid) 1591 goto out; 1592 1593 ASSERT(ISP2(blksz)); 1594 if (trunc) 1595 tail = 0; 1596 else 1597 tail = P2PHASE(len, blksz); 1598 1599 ASSERT0(P2PHASE(off, blksz)); 1600 /* zero out any partial block data at the end of the range */ 1601 if (tail) { 1602 if (len < tail) 1603 tail = len; 1604 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1605 TRUE, FTAG, &db) == 0) { 1606 /* don't dirty if not on disk and not dirty */ 1607 if (db->db_last_dirty || 1608 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1609 rw_exit(&dn->dn_struct_rwlock); 1610 dmu_buf_will_dirty(&db->db, tx); 1611 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1612 bzero(db->db.db_data, tail); 1613 } 1614 dbuf_rele(db, FTAG); 1615 } 1616 len -= tail; 1617 } 1618 1619 /* If the range did not include a full block, we are done */ 1620 if (len == 0) 1621 goto out; 1622 1623 ASSERT(IS_P2ALIGNED(off, blksz)); 1624 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1625 blkid = off >> blkshift; 1626 nblks = len >> blkshift; 1627 if (trunc) 1628 nblks += 1; 1629 1630 /* 1631 * Dirty all the indirect blocks in this range. Note that only 1632 * the first and last indirect blocks can actually be written 1633 * (if they were partially freed) -- they must be dirtied, even if 1634 * they do not exist on disk yet. The interior blocks will 1635 * be freed by free_children(), so they will not actually be written. 1636 * Even though these interior blocks will not be written, we 1637 * dirty them for two reasons: 1638 * 1639 * - It ensures that the indirect blocks remain in memory until 1640 * syncing context. (They have already been prefetched by 1641 * dmu_tx_hold_free(), so we don't have to worry about reading 1642 * them serially here.) 1643 * 1644 * - The dirty space accounting will put pressure on the txg sync 1645 * mechanism to begin syncing, and to delay transactions if there 1646 * is a large amount of freeing. Even though these indirect 1647 * blocks will not be written, we could need to write the same 1648 * amount of space if we copy the freed BPs into deadlists. 1649 */ 1650 if (dn->dn_nlevels > 1) { 1651 uint64_t first, last; 1652 1653 first = blkid >> epbs; 1654 dnode_dirty_l1(dn, first, tx); 1655 if (trunc) 1656 last = dn->dn_maxblkid >> epbs; 1657 else 1658 last = (blkid + nblks - 1) >> epbs; 1659 if (last != first) 1660 dnode_dirty_l1(dn, last, tx); 1661 1662 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 1663 SPA_BLKPTRSHIFT; 1664 for (uint64_t i = first + 1; i < last; i++) { 1665 /* 1666 * Set i to the blockid of the next non-hole 1667 * level-1 indirect block at or after i. Note 1668 * that dnode_next_offset() operates in terms of 1669 * level-0-equivalent bytes. 1670 */ 1671 uint64_t ibyte = i << shift; 1672 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, 1673 &ibyte, 2, 1, 0); 1674 i = ibyte >> shift; 1675 if (i >= last) 1676 break; 1677 1678 /* 1679 * Normally we should not see an error, either 1680 * from dnode_next_offset() or dbuf_hold_level() 1681 * (except for ESRCH from dnode_next_offset). 1682 * If there is an i/o error, then when we read 1683 * this block in syncing context, it will use 1684 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according 1685 * to the "failmode" property. dnode_next_offset() 1686 * doesn't have a flag to indicate MUSTSUCCEED. 1687 */ 1688 if (err != 0) 1689 break; 1690 1691 dnode_dirty_l1(dn, i, tx); 1692 } 1693 } 1694 1695done: 1696 /* 1697 * Add this range to the dnode range list. 1698 * We will finish up this free operation in the syncing phase. 1699 */ 1700 mutex_enter(&dn->dn_mtx); 1701 int txgoff = tx->tx_txg & TXG_MASK; 1702 if (dn->dn_free_ranges[txgoff] == NULL) { 1703 dn->dn_free_ranges[txgoff] = 1704 range_tree_create(NULL, NULL, &dn->dn_mtx); 1705 } 1706 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 1707 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 1708 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1709 blkid, nblks, tx->tx_txg); 1710 mutex_exit(&dn->dn_mtx); 1711 1712 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1713 dnode_setdirty(dn, tx); 1714out: 1715 1716 rw_exit(&dn->dn_struct_rwlock); 1717} 1718 1719static boolean_t 1720dnode_spill_freed(dnode_t *dn) 1721{ 1722 int i; 1723 1724 mutex_enter(&dn->dn_mtx); 1725 for (i = 0; i < TXG_SIZE; i++) { 1726 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1727 break; 1728 } 1729 mutex_exit(&dn->dn_mtx); 1730 return (i < TXG_SIZE); 1731} 1732 1733/* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1734uint64_t 1735dnode_block_freed(dnode_t *dn, uint64_t blkid) 1736{ 1737 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1738 int i; 1739 1740 if (blkid == DMU_BONUS_BLKID) 1741 return (FALSE); 1742 1743 /* 1744 * If we're in the process of opening the pool, dp will not be 1745 * set yet, but there shouldn't be anything dirty. 1746 */ 1747 if (dp == NULL) 1748 return (FALSE); 1749 1750 if (dn->dn_free_txg) 1751 return (TRUE); 1752 1753 if (blkid == DMU_SPILL_BLKID) 1754 return (dnode_spill_freed(dn)); 1755 1756 mutex_enter(&dn->dn_mtx); 1757 for (i = 0; i < TXG_SIZE; i++) { 1758 if (dn->dn_free_ranges[i] != NULL && 1759 range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 1760 break; 1761 } 1762 mutex_exit(&dn->dn_mtx); 1763 return (i < TXG_SIZE); 1764} 1765 1766/* call from syncing context when we actually write/free space for this dnode */ 1767void 1768dnode_diduse_space(dnode_t *dn, int64_t delta) 1769{ 1770 uint64_t space; 1771 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1772 dn, dn->dn_phys, 1773 (u_longlong_t)dn->dn_phys->dn_used, 1774 (longlong_t)delta); 1775 1776 mutex_enter(&dn->dn_mtx); 1777 space = DN_USED_BYTES(dn->dn_phys); 1778 if (delta > 0) { 1779 ASSERT3U(space + delta, >=, space); /* no overflow */ 1780 } else { 1781 ASSERT3U(space, >=, -delta); /* no underflow */ 1782 } 1783 space += delta; 1784 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1785 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1786 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 1787 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1788 } else { 1789 dn->dn_phys->dn_used = space; 1790 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1791 } 1792 mutex_exit(&dn->dn_mtx); 1793} 1794 1795/* 1796 * Call when we think we're going to write/free space in open context to track 1797 * the amount of memory in use by the currently open txg. 1798 */ 1799void 1800dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1801{ 1802 objset_t *os = dn->dn_objset; 1803 dsl_dataset_t *ds = os->os_dsl_dataset; 1804 int64_t aspace = spa_get_asize(os->os_spa, space); 1805 1806 if (ds != NULL) { 1807 dsl_dir_willuse_space(ds->ds_dir, aspace, tx); 1808 dsl_pool_dirty_space(dmu_tx_pool(tx), space, tx); 1809 } 1810 1811 dmu_tx_willuse_space(tx, aspace); 1812} 1813 1814/* 1815 * Scans a block at the indicated "level" looking for a hole or data, 1816 * depending on 'flags'. 1817 * 1818 * If level > 0, then we are scanning an indirect block looking at its 1819 * pointers. If level == 0, then we are looking at a block of dnodes. 1820 * 1821 * If we don't find what we are looking for in the block, we return ESRCH. 1822 * Otherwise, return with *offset pointing to the beginning (if searching 1823 * forwards) or end (if searching backwards) of the range covered by the 1824 * block pointer we matched on (or dnode). 1825 * 1826 * The basic search algorithm used below by dnode_next_offset() is to 1827 * use this function to search up the block tree (widen the search) until 1828 * we find something (i.e., we don't return ESRCH) and then search back 1829 * down the tree (narrow the search) until we reach our original search 1830 * level. 1831 */ 1832static int 1833dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1834 int lvl, uint64_t blkfill, uint64_t txg) 1835{ 1836 dmu_buf_impl_t *db = NULL; 1837 void *data = NULL; 1838 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1839 uint64_t epb = 1ULL << epbs; 1840 uint64_t minfill, maxfill; 1841 boolean_t hole; 1842 int i, inc, error, span; 1843 1844 dprintf("probing object %llu offset %llx level %d of %u\n", 1845 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1846 1847 hole = ((flags & DNODE_FIND_HOLE) != 0); 1848 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1849 ASSERT(txg == 0 || !hole); 1850 1851 if (lvl == dn->dn_phys->dn_nlevels) { 1852 error = 0; 1853 epb = dn->dn_phys->dn_nblkptr; 1854 data = dn->dn_phys->dn_blkptr; 1855 } else { 1856 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1857 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1858 if (error) { 1859 if (error != ENOENT) 1860 return (error); 1861 if (hole) 1862 return (0); 1863 /* 1864 * This can only happen when we are searching up 1865 * the block tree for data. We don't really need to 1866 * adjust the offset, as we will just end up looking 1867 * at the pointer to this block in its parent, and its 1868 * going to be unallocated, so we will skip over it. 1869 */ 1870 return (SET_ERROR(ESRCH)); 1871 } 1872 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1873 if (error) { 1874 dbuf_rele(db, FTAG); 1875 return (error); 1876 } 1877 data = db->db.db_data; 1878 } 1879 1880 1881 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 1882 db->db_blkptr->blk_birth <= txg || 1883 BP_IS_HOLE(db->db_blkptr))) { 1884 /* 1885 * This can only happen when we are searching up the tree 1886 * and these conditions mean that we need to keep climbing. 1887 */ 1888 error = SET_ERROR(ESRCH); 1889 } else if (lvl == 0) { 1890 dnode_phys_t *dnp = data; 1891 span = DNODE_SHIFT; 1892 ASSERT(dn->dn_type == DMU_OT_DNODE); 1893 1894 for (i = (*offset >> span) & (blkfill - 1); 1895 i >= 0 && i < blkfill; i += inc) { 1896 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1897 break; 1898 *offset += (1ULL << span) * inc; 1899 } 1900 if (i < 0 || i == blkfill) 1901 error = SET_ERROR(ESRCH); 1902 } else { 1903 blkptr_t *bp = data; 1904 uint64_t start = *offset; 1905 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1906 minfill = 0; 1907 maxfill = blkfill << ((lvl - 1) * epbs); 1908 1909 if (hole) 1910 maxfill--; 1911 else 1912 minfill++; 1913 1914 *offset = *offset >> span; 1915 for (i = BF64_GET(*offset, 0, epbs); 1916 i >= 0 && i < epb; i += inc) { 1917 if (BP_GET_FILL(&bp[i]) >= minfill && 1918 BP_GET_FILL(&bp[i]) <= maxfill && 1919 (hole || bp[i].blk_birth > txg)) 1920 break; 1921 if (inc > 0 || *offset > 0) 1922 *offset += inc; 1923 } 1924 *offset = *offset << span; 1925 if (inc < 0) { 1926 /* traversing backwards; position offset at the end */ 1927 ASSERT3U(*offset, <=, start); 1928 *offset = MIN(*offset + (1ULL << span) - 1, start); 1929 } else if (*offset < start) { 1930 *offset = start; 1931 } 1932 if (i < 0 || i >= epb) 1933 error = SET_ERROR(ESRCH); 1934 } 1935 1936 if (db) 1937 dbuf_rele(db, FTAG); 1938 1939 return (error); 1940} 1941 1942/* 1943 * Find the next hole, data, or sparse region at or after *offset. 1944 * The value 'blkfill' tells us how many items we expect to find 1945 * in an L0 data block; this value is 1 for normal objects, 1946 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1947 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1948 * 1949 * Examples: 1950 * 1951 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1952 * Finds the next/previous hole/data in a file. 1953 * Used in dmu_offset_next(). 1954 * 1955 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1956 * Finds the next free/allocated dnode an objset's meta-dnode. 1957 * Only finds objects that have new contents since txg (ie. 1958 * bonus buffer changes and content removal are ignored). 1959 * Used in dmu_object_next(). 1960 * 1961 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1962 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1963 * Used in dmu_object_alloc(). 1964 */ 1965int 1966dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1967 int minlvl, uint64_t blkfill, uint64_t txg) 1968{ 1969 uint64_t initial_offset = *offset; 1970 int lvl, maxlvl; 1971 int error = 0; 1972 1973 if (!(flags & DNODE_FIND_HAVELOCK)) 1974 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1975 1976 if (dn->dn_phys->dn_nlevels == 0) { 1977 error = SET_ERROR(ESRCH); 1978 goto out; 1979 } 1980 1981 if (dn->dn_datablkshift == 0) { 1982 if (*offset < dn->dn_datablksz) { 1983 if (flags & DNODE_FIND_HOLE) 1984 *offset = dn->dn_datablksz; 1985 } else { 1986 error = SET_ERROR(ESRCH); 1987 } 1988 goto out; 1989 } 1990 1991 maxlvl = dn->dn_phys->dn_nlevels; 1992 1993 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1994 error = dnode_next_offset_level(dn, 1995 flags, offset, lvl, blkfill, txg); 1996 if (error != ESRCH) 1997 break; 1998 } 1999 2000 while (error == 0 && --lvl >= minlvl) { 2001 error = dnode_next_offset_level(dn, 2002 flags, offset, lvl, blkfill, txg); 2003 } 2004 2005 /* 2006 * There's always a "virtual hole" at the end of the object, even 2007 * if all BP's which physically exist are non-holes. 2008 */ 2009 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 && 2010 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) { 2011 error = 0; 2012 } 2013 2014 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 2015 initial_offset < *offset : initial_offset > *offset)) 2016 error = SET_ERROR(ESRCH); 2017out: 2018 if (!(flags & DNODE_FIND_HAVELOCK)) 2019 rw_exit(&dn->dn_struct_rwlock); 2020 2021 return (error); 2022} 2023