dnode.c revision 269845
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, 2014 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 } else if (d1->db_level > d2->db_level) { 73 return (1); 74 } 75 76 if (d1->db_blkid < d2->db_blkid) { 77 return (-1); 78 } else if (d1->db_blkid > d2->db_blkid) { 79 return (1); 80 } 81 82 /* 83 * If a dbuf is being evicted while dn_dbufs_mutex is not held, we set 84 * the db_state to DB_EVICTING but do not remove it from dn_dbufs. If 85 * another thread creates a dbuf of the same blkid before the dbuf is 86 * removed from dn_dbufs, we can reach a state where there are two 87 * dbufs of the same blkid and level in db_dbufs. To maintain the avl 88 * invariant that there cannot be duplicate items, we distinguish 89 * between these two dbufs based on the time they were created. 90 */ 91 if (d1->db_creation < d2->db_creation) { 92 return (-1); 93 } else if (d1->db_creation > d2->db_creation) { 94 return (1); 95 } else { 96 ASSERT3P(d1, ==, d2); 97 return (0); 98 } 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 if (blocksize == 0) 515 blocksize = 1 << zfs_default_bs; 516 else if (blocksize > SPA_MAXBLOCKSIZE) 517 blocksize = SPA_MAXBLOCKSIZE; 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, <=, SPA_MAXBLOCKSIZE); 599 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 600 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 601 ASSERT(tx->tx_txg != 0); 602 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 603 (bonustype != DMU_OT_NONE && bonuslen != 0) || 604 (bonustype == DMU_OT_SA && bonuslen == 0)); 605 ASSERT(DMU_OT_IS_VALID(bonustype)); 606 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 607 608 /* clean up any unreferenced dbufs */ 609 dnode_evict_dbufs(dn); 610 611 dn->dn_id_flags = 0; 612 613 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 614 dnode_setdirty(dn, tx); 615 if (dn->dn_datablksz != blocksize) { 616 /* change blocksize */ 617 ASSERT(dn->dn_maxblkid == 0 && 618 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 619 dnode_block_freed(dn, 0))); 620 dnode_setdblksz(dn, blocksize); 621 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 622 } 623 if (dn->dn_bonuslen != bonuslen) 624 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 625 626 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 627 nblkptr = 1; 628 else 629 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 630 if (dn->dn_bonustype != bonustype) 631 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 632 if (dn->dn_nblkptr != nblkptr) 633 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 634 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 635 dbuf_rm_spill(dn, tx); 636 dnode_rm_spill(dn, tx); 637 } 638 rw_exit(&dn->dn_struct_rwlock); 639 640 /* change type */ 641 dn->dn_type = ot; 642 643 /* change bonus size and type */ 644 mutex_enter(&dn->dn_mtx); 645 dn->dn_bonustype = bonustype; 646 dn->dn_bonuslen = bonuslen; 647 dn->dn_nblkptr = nblkptr; 648 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 649 dn->dn_compress = ZIO_COMPRESS_INHERIT; 650 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 651 652 /* fix up the bonus db_size */ 653 if (dn->dn_bonus) { 654 dn->dn_bonus->db.db_size = 655 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 656 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 657 } 658 659 dn->dn_allocated_txg = tx->tx_txg; 660 mutex_exit(&dn->dn_mtx); 661} 662 663#ifdef DNODE_STATS 664static struct { 665 uint64_t dms_dnode_invalid; 666 uint64_t dms_dnode_recheck1; 667 uint64_t dms_dnode_recheck2; 668 uint64_t dms_dnode_special; 669 uint64_t dms_dnode_handle; 670 uint64_t dms_dnode_rwlock; 671 uint64_t dms_dnode_active; 672} dnode_move_stats; 673#endif /* DNODE_STATS */ 674 675static void 676dnode_move_impl(dnode_t *odn, dnode_t *ndn) 677{ 678 int i; 679 680 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 681 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 682 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 683 ASSERT(!RW_LOCK_HELD(&odn->dn_zfetch.zf_rwlock)); 684 685 /* Copy fields. */ 686 ndn->dn_objset = odn->dn_objset; 687 ndn->dn_object = odn->dn_object; 688 ndn->dn_dbuf = odn->dn_dbuf; 689 ndn->dn_handle = odn->dn_handle; 690 ndn->dn_phys = odn->dn_phys; 691 ndn->dn_type = odn->dn_type; 692 ndn->dn_bonuslen = odn->dn_bonuslen; 693 ndn->dn_bonustype = odn->dn_bonustype; 694 ndn->dn_nblkptr = odn->dn_nblkptr; 695 ndn->dn_checksum = odn->dn_checksum; 696 ndn->dn_compress = odn->dn_compress; 697 ndn->dn_nlevels = odn->dn_nlevels; 698 ndn->dn_indblkshift = odn->dn_indblkshift; 699 ndn->dn_datablkshift = odn->dn_datablkshift; 700 ndn->dn_datablkszsec = odn->dn_datablkszsec; 701 ndn->dn_datablksz = odn->dn_datablksz; 702 ndn->dn_maxblkid = odn->dn_maxblkid; 703 bcopy(&odn->dn_next_nblkptr[0], &ndn->dn_next_nblkptr[0], 704 sizeof (odn->dn_next_nblkptr)); 705 bcopy(&odn->dn_next_nlevels[0], &ndn->dn_next_nlevels[0], 706 sizeof (odn->dn_next_nlevels)); 707 bcopy(&odn->dn_next_indblkshift[0], &ndn->dn_next_indblkshift[0], 708 sizeof (odn->dn_next_indblkshift)); 709 bcopy(&odn->dn_next_bonustype[0], &ndn->dn_next_bonustype[0], 710 sizeof (odn->dn_next_bonustype)); 711 bcopy(&odn->dn_rm_spillblk[0], &ndn->dn_rm_spillblk[0], 712 sizeof (odn->dn_rm_spillblk)); 713 bcopy(&odn->dn_next_bonuslen[0], &ndn->dn_next_bonuslen[0], 714 sizeof (odn->dn_next_bonuslen)); 715 bcopy(&odn->dn_next_blksz[0], &ndn->dn_next_blksz[0], 716 sizeof (odn->dn_next_blksz)); 717 for (i = 0; i < TXG_SIZE; i++) { 718 list_move_tail(&ndn->dn_dirty_records[i], 719 &odn->dn_dirty_records[i]); 720 } 721 bcopy(&odn->dn_free_ranges[0], &ndn->dn_free_ranges[0], 722 sizeof (odn->dn_free_ranges)); 723 ndn->dn_allocated_txg = odn->dn_allocated_txg; 724 ndn->dn_free_txg = odn->dn_free_txg; 725 ndn->dn_assigned_txg = odn->dn_assigned_txg; 726 ndn->dn_dirtyctx = odn->dn_dirtyctx; 727 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 728 ASSERT(refcount_count(&odn->dn_tx_holds) == 0); 729 refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 730 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 731 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 732 ndn->dn_dbufs_count = odn->dn_dbufs_count; 733 ndn->dn_unlisted_l0_blkid = odn->dn_unlisted_l0_blkid; 734 ndn->dn_bonus = odn->dn_bonus; 735 ndn->dn_have_spill = odn->dn_have_spill; 736 ndn->dn_zio = odn->dn_zio; 737 ndn->dn_oldused = odn->dn_oldused; 738 ndn->dn_oldflags = odn->dn_oldflags; 739 ndn->dn_olduid = odn->dn_olduid; 740 ndn->dn_oldgid = odn->dn_oldgid; 741 ndn->dn_newuid = odn->dn_newuid; 742 ndn->dn_newgid = odn->dn_newgid; 743 ndn->dn_id_flags = odn->dn_id_flags; 744 dmu_zfetch_init(&ndn->dn_zfetch, NULL); 745 list_move_tail(&ndn->dn_zfetch.zf_stream, &odn->dn_zfetch.zf_stream); 746 ndn->dn_zfetch.zf_dnode = odn->dn_zfetch.zf_dnode; 747 ndn->dn_zfetch.zf_stream_cnt = odn->dn_zfetch.zf_stream_cnt; 748 ndn->dn_zfetch.zf_alloc_fail = odn->dn_zfetch.zf_alloc_fail; 749 750 /* 751 * Update back pointers. Updating the handle fixes the back pointer of 752 * every descendant dbuf as well as the bonus dbuf. 753 */ 754 ASSERT(ndn->dn_handle->dnh_dnode == odn); 755 ndn->dn_handle->dnh_dnode = ndn; 756 if (ndn->dn_zfetch.zf_dnode == odn) { 757 ndn->dn_zfetch.zf_dnode = ndn; 758 } 759 760 /* 761 * Invalidate the original dnode by clearing all of its back pointers. 762 */ 763 odn->dn_dbuf = NULL; 764 odn->dn_handle = NULL; 765 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 766 offsetof(dmu_buf_impl_t, db_link)); 767 odn->dn_dbufs_count = 0; 768 odn->dn_unlisted_l0_blkid = 0; 769 odn->dn_bonus = NULL; 770 odn->dn_zfetch.zf_dnode = NULL; 771 772 /* 773 * Set the low bit of the objset pointer to ensure that dnode_move() 774 * recognizes the dnode as invalid in any subsequent callback. 775 */ 776 POINTER_INVALIDATE(&odn->dn_objset); 777 778 /* 779 * Satisfy the destructor. 780 */ 781 for (i = 0; i < TXG_SIZE; i++) { 782 list_create(&odn->dn_dirty_records[i], 783 sizeof (dbuf_dirty_record_t), 784 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 785 odn->dn_free_ranges[i] = NULL; 786 odn->dn_next_nlevels[i] = 0; 787 odn->dn_next_indblkshift[i] = 0; 788 odn->dn_next_bonustype[i] = 0; 789 odn->dn_rm_spillblk[i] = 0; 790 odn->dn_next_bonuslen[i] = 0; 791 odn->dn_next_blksz[i] = 0; 792 } 793 odn->dn_allocated_txg = 0; 794 odn->dn_free_txg = 0; 795 odn->dn_assigned_txg = 0; 796 odn->dn_dirtyctx = 0; 797 odn->dn_dirtyctx_firstset = NULL; 798 odn->dn_have_spill = B_FALSE; 799 odn->dn_zio = NULL; 800 odn->dn_oldused = 0; 801 odn->dn_oldflags = 0; 802 odn->dn_olduid = 0; 803 odn->dn_oldgid = 0; 804 odn->dn_newuid = 0; 805 odn->dn_newgid = 0; 806 odn->dn_id_flags = 0; 807 808 /* 809 * Mark the dnode. 810 */ 811 ndn->dn_moved = 1; 812 odn->dn_moved = (uint8_t)-1; 813} 814 815#ifdef sun 816#ifdef _KERNEL 817/*ARGSUSED*/ 818static kmem_cbrc_t 819dnode_move(void *buf, void *newbuf, size_t size, void *arg) 820{ 821 dnode_t *odn = buf, *ndn = newbuf; 822 objset_t *os; 823 int64_t refcount; 824 uint32_t dbufs; 825 826 /* 827 * The dnode is on the objset's list of known dnodes if the objset 828 * pointer is valid. We set the low bit of the objset pointer when 829 * freeing the dnode to invalidate it, and the memory patterns written 830 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 831 * A newly created dnode sets the objset pointer last of all to indicate 832 * that the dnode is known and in a valid state to be moved by this 833 * function. 834 */ 835 os = odn->dn_objset; 836 if (!POINTER_IS_VALID(os)) { 837 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_invalid); 838 return (KMEM_CBRC_DONT_KNOW); 839 } 840 841 /* 842 * Ensure that the objset does not go away during the move. 843 */ 844 rw_enter(&os_lock, RW_WRITER); 845 if (os != odn->dn_objset) { 846 rw_exit(&os_lock); 847 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck1); 848 return (KMEM_CBRC_DONT_KNOW); 849 } 850 851 /* 852 * If the dnode is still valid, then so is the objset. We know that no 853 * valid objset can be freed while we hold os_lock, so we can safely 854 * ensure that the objset remains in use. 855 */ 856 mutex_enter(&os->os_lock); 857 858 /* 859 * Recheck the objset pointer in case the dnode was removed just before 860 * acquiring the lock. 861 */ 862 if (os != odn->dn_objset) { 863 mutex_exit(&os->os_lock); 864 rw_exit(&os_lock); 865 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck2); 866 return (KMEM_CBRC_DONT_KNOW); 867 } 868 869 /* 870 * At this point we know that as long as we hold os->os_lock, the dnode 871 * cannot be freed and fields within the dnode can be safely accessed. 872 * The objset listing this dnode cannot go away as long as this dnode is 873 * on its list. 874 */ 875 rw_exit(&os_lock); 876 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 877 mutex_exit(&os->os_lock); 878 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_special); 879 return (KMEM_CBRC_NO); 880 } 881 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 882 883 /* 884 * Lock the dnode handle to prevent the dnode from obtaining any new 885 * holds. This also prevents the descendant dbufs and the bonus dbuf 886 * from accessing the dnode, so that we can discount their holds. The 887 * handle is safe to access because we know that while the dnode cannot 888 * go away, neither can its handle. Once we hold dnh_zrlock, we can 889 * safely move any dnode referenced only by dbufs. 890 */ 891 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 892 mutex_exit(&os->os_lock); 893 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_handle); 894 return (KMEM_CBRC_LATER); 895 } 896 897 /* 898 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 899 * We need to guarantee that there is a hold for every dbuf in order to 900 * determine whether the dnode is actively referenced. Falsely matching 901 * a dbuf to an active hold would lead to an unsafe move. It's possible 902 * that a thread already having an active dnode hold is about to add a 903 * dbuf, and we can't compare hold and dbuf counts while the add is in 904 * progress. 905 */ 906 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 907 zrl_exit(&odn->dn_handle->dnh_zrlock); 908 mutex_exit(&os->os_lock); 909 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_rwlock); 910 return (KMEM_CBRC_LATER); 911 } 912 913 /* 914 * A dbuf may be removed (evicted) without an active dnode hold. In that 915 * case, the dbuf count is decremented under the handle lock before the 916 * dbuf's hold is released. This order ensures that if we count the hold 917 * after the dbuf is removed but before its hold is released, we will 918 * treat the unmatched hold as active and exit safely. If we count the 919 * hold before the dbuf is removed, the hold is discounted, and the 920 * removal is blocked until the move completes. 921 */ 922 refcount = refcount_count(&odn->dn_holds); 923 ASSERT(refcount >= 0); 924 dbufs = odn->dn_dbufs_count; 925 926 /* We can't have more dbufs than dnode holds. */ 927 ASSERT3U(dbufs, <=, refcount); 928 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 929 uint32_t, dbufs); 930 931 if (refcount > dbufs) { 932 rw_exit(&odn->dn_struct_rwlock); 933 zrl_exit(&odn->dn_handle->dnh_zrlock); 934 mutex_exit(&os->os_lock); 935 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_active); 936 return (KMEM_CBRC_LATER); 937 } 938 939 rw_exit(&odn->dn_struct_rwlock); 940 941 /* 942 * At this point we know that anyone with a hold on the dnode is not 943 * actively referencing it. The dnode is known and in a valid state to 944 * move. We're holding the locks needed to execute the critical section. 945 */ 946 dnode_move_impl(odn, ndn); 947 948 list_link_replace(&odn->dn_link, &ndn->dn_link); 949 /* If the dnode was safe to move, the refcount cannot have changed. */ 950 ASSERT(refcount == refcount_count(&ndn->dn_holds)); 951 ASSERT(dbufs == ndn->dn_dbufs_count); 952 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 953 mutex_exit(&os->os_lock); 954 955 return (KMEM_CBRC_YES); 956} 957#endif /* _KERNEL */ 958#endif /* sun */ 959 960void 961dnode_special_close(dnode_handle_t *dnh) 962{ 963 dnode_t *dn = dnh->dnh_dnode; 964 965 /* 966 * Wait for final references to the dnode to clear. This can 967 * only happen if the arc is asyncronously evicting state that 968 * has a hold on this dnode while we are trying to evict this 969 * dnode. 970 */ 971 while (refcount_count(&dn->dn_holds) > 0) 972 delay(1); 973 zrl_add(&dnh->dnh_zrlock); 974 dnode_destroy(dn); /* implicit zrl_remove() */ 975 zrl_destroy(&dnh->dnh_zrlock); 976 dnh->dnh_dnode = NULL; 977} 978 979dnode_t * 980dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 981 dnode_handle_t *dnh) 982{ 983 dnode_t *dn = dnode_create(os, dnp, NULL, object, dnh); 984 dnh->dnh_dnode = dn; 985 zrl_init(&dnh->dnh_zrlock); 986 DNODE_VERIFY(dn); 987 return (dn); 988} 989 990static void 991dnode_buf_pageout(dmu_buf_t *db, void *arg) 992{ 993 dnode_children_t *children_dnodes = arg; 994 int i; 995 int epb = db->db_size >> DNODE_SHIFT; 996 997 ASSERT(epb == children_dnodes->dnc_count); 998 999 for (i = 0; i < epb; i++) { 1000 dnode_handle_t *dnh = &children_dnodes->dnc_children[i]; 1001 dnode_t *dn; 1002 1003 /* 1004 * The dnode handle lock guards against the dnode moving to 1005 * another valid address, so there is no need here to guard 1006 * against changes to or from NULL. 1007 */ 1008 if (dnh->dnh_dnode == NULL) { 1009 zrl_destroy(&dnh->dnh_zrlock); 1010 continue; 1011 } 1012 1013 zrl_add(&dnh->dnh_zrlock); 1014 dn = dnh->dnh_dnode; 1015 /* 1016 * If there are holds on this dnode, then there should 1017 * be holds on the dnode's containing dbuf as well; thus 1018 * it wouldn't be eligible for eviction and this function 1019 * would not have been called. 1020 */ 1021 ASSERT(refcount_is_zero(&dn->dn_holds)); 1022 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 1023 1024 dnode_destroy(dn); /* implicit zrl_remove() */ 1025 zrl_destroy(&dnh->dnh_zrlock); 1026 dnh->dnh_dnode = NULL; 1027 } 1028 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1029 (epb - 1) * sizeof (dnode_handle_t)); 1030} 1031 1032/* 1033 * errors: 1034 * EINVAL - invalid object number. 1035 * EIO - i/o error. 1036 * succeeds even for free dnodes. 1037 */ 1038int 1039dnode_hold_impl(objset_t *os, uint64_t object, int flag, 1040 void *tag, dnode_t **dnp) 1041{ 1042 int epb, idx, err; 1043 int drop_struct_lock = FALSE; 1044 int type; 1045 uint64_t blk; 1046 dnode_t *mdn, *dn; 1047 dmu_buf_impl_t *db; 1048 dnode_children_t *children_dnodes; 1049 dnode_handle_t *dnh; 1050 1051 /* 1052 * If you are holding the spa config lock as writer, you shouldn't 1053 * be asking the DMU to do *anything* unless it's the root pool 1054 * which may require us to read from the root filesystem while 1055 * holding some (not all) of the locks as writer. 1056 */ 1057 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1058 (spa_is_root(os->os_spa) && 1059 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1060 1061 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 1062 dn = (object == DMU_USERUSED_OBJECT) ? 1063 DMU_USERUSED_DNODE(os) : DMU_GROUPUSED_DNODE(os); 1064 if (dn == NULL) 1065 return (SET_ERROR(ENOENT)); 1066 type = dn->dn_type; 1067 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1068 return (SET_ERROR(ENOENT)); 1069 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1070 return (SET_ERROR(EEXIST)); 1071 DNODE_VERIFY(dn); 1072 (void) refcount_add(&dn->dn_holds, tag); 1073 *dnp = dn; 1074 return (0); 1075 } 1076 1077 if (object == 0 || object >= DN_MAX_OBJECT) 1078 return (SET_ERROR(EINVAL)); 1079 1080 mdn = DMU_META_DNODE(os); 1081 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1082 1083 DNODE_VERIFY(mdn); 1084 1085 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1086 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1087 drop_struct_lock = TRUE; 1088 } 1089 1090 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 1091 1092 db = dbuf_hold(mdn, blk, FTAG); 1093 if (drop_struct_lock) 1094 rw_exit(&mdn->dn_struct_rwlock); 1095 if (db == NULL) 1096 return (SET_ERROR(EIO)); 1097 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 1098 if (err) { 1099 dbuf_rele(db, FTAG); 1100 return (err); 1101 } 1102 1103 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1104 epb = db->db.db_size >> DNODE_SHIFT; 1105 1106 idx = object & (epb-1); 1107 1108 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1109 children_dnodes = dmu_buf_get_user(&db->db); 1110 if (children_dnodes == NULL) { 1111 int i; 1112 dnode_children_t *winner; 1113 children_dnodes = kmem_zalloc(sizeof (dnode_children_t) + 1114 (epb - 1) * sizeof (dnode_handle_t), KM_SLEEP); 1115 children_dnodes->dnc_count = epb; 1116 dnh = &children_dnodes->dnc_children[0]; 1117 for (i = 0; i < epb; i++) { 1118 zrl_init(&dnh[i].dnh_zrlock); 1119 dnh[i].dnh_dnode = NULL; 1120 } 1121 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 1122 dnode_buf_pageout)) { 1123 1124 for (i = 0; i < epb; i++) { 1125 zrl_destroy(&dnh[i].dnh_zrlock); 1126 } 1127 1128 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1129 (epb - 1) * sizeof (dnode_handle_t)); 1130 children_dnodes = winner; 1131 } 1132 } 1133 ASSERT(children_dnodes->dnc_count == epb); 1134 1135 dnh = &children_dnodes->dnc_children[idx]; 1136 zrl_add(&dnh->dnh_zrlock); 1137 if ((dn = dnh->dnh_dnode) == NULL) { 1138 dnode_phys_t *phys = (dnode_phys_t *)db->db.db_data+idx; 1139 dnode_t *winner; 1140 1141 dn = dnode_create(os, phys, db, object, dnh); 1142 winner = atomic_cas_ptr(&dnh->dnh_dnode, NULL, dn); 1143 if (winner != NULL) { 1144 zrl_add(&dnh->dnh_zrlock); 1145 dnode_destroy(dn); /* implicit zrl_remove() */ 1146 dn = winner; 1147 } 1148 } 1149 1150 mutex_enter(&dn->dn_mtx); 1151 type = dn->dn_type; 1152 if (dn->dn_free_txg || 1153 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 1154 ((flag & DNODE_MUST_BE_FREE) && 1155 (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) { 1156 mutex_exit(&dn->dn_mtx); 1157 zrl_remove(&dnh->dnh_zrlock); 1158 dbuf_rele(db, FTAG); 1159 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 1160 } 1161 mutex_exit(&dn->dn_mtx); 1162 1163 if (refcount_add(&dn->dn_holds, tag) == 1) 1164 dbuf_add_ref(db, dnh); 1165 /* Now we can rely on the hold to prevent the dnode from moving. */ 1166 zrl_remove(&dnh->dnh_zrlock); 1167 1168 DNODE_VERIFY(dn); 1169 ASSERT3P(dn->dn_dbuf, ==, db); 1170 ASSERT3U(dn->dn_object, ==, object); 1171 dbuf_rele(db, FTAG); 1172 1173 *dnp = dn; 1174 return (0); 1175} 1176 1177/* 1178 * Return held dnode if the object is allocated, NULL if not. 1179 */ 1180int 1181dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 1182{ 1183 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 1184} 1185 1186/* 1187 * Can only add a reference if there is already at least one 1188 * reference on the dnode. Returns FALSE if unable to add a 1189 * new reference. 1190 */ 1191boolean_t 1192dnode_add_ref(dnode_t *dn, void *tag) 1193{ 1194 mutex_enter(&dn->dn_mtx); 1195 if (refcount_is_zero(&dn->dn_holds)) { 1196 mutex_exit(&dn->dn_mtx); 1197 return (FALSE); 1198 } 1199 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 1200 mutex_exit(&dn->dn_mtx); 1201 return (TRUE); 1202} 1203 1204void 1205dnode_rele(dnode_t *dn, void *tag) 1206{ 1207 uint64_t refs; 1208 /* Get while the hold prevents the dnode from moving. */ 1209 dmu_buf_impl_t *db = dn->dn_dbuf; 1210 dnode_handle_t *dnh = dn->dn_handle; 1211 1212 mutex_enter(&dn->dn_mtx); 1213 refs = refcount_remove(&dn->dn_holds, tag); 1214 mutex_exit(&dn->dn_mtx); 1215 1216 /* 1217 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1218 * indirectly by dbuf_rele() while relying on the dnode handle to 1219 * prevent the dnode from moving, since releasing the last hold could 1220 * result in the dnode's parent dbuf evicting its dnode handles. For 1221 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1222 * other direct or indirect hold on the dnode must first drop the dnode 1223 * handle. 1224 */ 1225 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread); 1226 1227 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1228 if (refs == 0 && db != NULL) { 1229 /* 1230 * Another thread could add a hold to the dnode handle in 1231 * dnode_hold_impl() while holding the parent dbuf. Since the 1232 * hold on the parent dbuf prevents the handle from being 1233 * destroyed, the hold on the handle is OK. We can't yet assert 1234 * that the handle has zero references, but that will be 1235 * asserted anyway when the handle gets destroyed. 1236 */ 1237 dbuf_rele(db, dnh); 1238 } 1239} 1240 1241void 1242dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1243{ 1244 objset_t *os = dn->dn_objset; 1245 uint64_t txg = tx->tx_txg; 1246 1247 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1248 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1249 return; 1250 } 1251 1252 DNODE_VERIFY(dn); 1253 1254#ifdef ZFS_DEBUG 1255 mutex_enter(&dn->dn_mtx); 1256 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1257 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1258 mutex_exit(&dn->dn_mtx); 1259#endif 1260 1261 /* 1262 * Determine old uid/gid when necessary 1263 */ 1264 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1265 1266 mutex_enter(&os->os_lock); 1267 1268 /* 1269 * If we are already marked dirty, we're done. 1270 */ 1271 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1272 mutex_exit(&os->os_lock); 1273 return; 1274 } 1275 1276 ASSERT(!refcount_is_zero(&dn->dn_holds) || 1277 !avl_is_empty(&dn->dn_dbufs)); 1278 ASSERT(dn->dn_datablksz != 0); 1279 ASSERT0(dn->dn_next_bonuslen[txg&TXG_MASK]); 1280 ASSERT0(dn->dn_next_blksz[txg&TXG_MASK]); 1281 ASSERT0(dn->dn_next_bonustype[txg&TXG_MASK]); 1282 1283 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1284 dn->dn_object, txg); 1285 1286 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 1287 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 1288 } else { 1289 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 1290 } 1291 1292 mutex_exit(&os->os_lock); 1293 1294 /* 1295 * The dnode maintains a hold on its containing dbuf as 1296 * long as there are holds on it. Each instantiated child 1297 * dbuf maintains a hold on the dnode. When the last child 1298 * drops its hold, the dnode will drop its hold on the 1299 * containing dbuf. We add a "dirty hold" here so that the 1300 * dnode will hang around after we finish processing its 1301 * children. 1302 */ 1303 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1304 1305 (void) dbuf_dirty(dn->dn_dbuf, tx); 1306 1307 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1308} 1309 1310void 1311dnode_free(dnode_t *dn, dmu_tx_t *tx) 1312{ 1313 int txgoff = tx->tx_txg & TXG_MASK; 1314 1315 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 1316 1317 /* we should be the only holder... hopefully */ 1318 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 1319 1320 mutex_enter(&dn->dn_mtx); 1321 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1322 mutex_exit(&dn->dn_mtx); 1323 return; 1324 } 1325 dn->dn_free_txg = tx->tx_txg; 1326 mutex_exit(&dn->dn_mtx); 1327 1328 /* 1329 * If the dnode is already dirty, it needs to be moved from 1330 * the dirty list to the free list. 1331 */ 1332 mutex_enter(&dn->dn_objset->os_lock); 1333 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 1334 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 1335 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 1336 mutex_exit(&dn->dn_objset->os_lock); 1337 } else { 1338 mutex_exit(&dn->dn_objset->os_lock); 1339 dnode_setdirty(dn, tx); 1340 } 1341} 1342 1343/* 1344 * Try to change the block size for the indicated dnode. This can only 1345 * succeed if there are no blocks allocated or dirty beyond first block 1346 */ 1347int 1348dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1349{ 1350 dmu_buf_impl_t *db; 1351 int err; 1352 1353 if (size == 0) 1354 size = SPA_MINBLOCKSIZE; 1355 if (size > SPA_MAXBLOCKSIZE) 1356 size = SPA_MAXBLOCKSIZE; 1357 else 1358 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1359 1360 if (ibs == dn->dn_indblkshift) 1361 ibs = 0; 1362 1363 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 1364 return (0); 1365 1366 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1367 1368 /* Check for any allocated blocks beyond the first */ 1369 if (dn->dn_maxblkid != 0) 1370 goto fail; 1371 1372 mutex_enter(&dn->dn_dbufs_mtx); 1373 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1374 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1375 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1376 db->db_blkid != DMU_SPILL_BLKID) { 1377 mutex_exit(&dn->dn_dbufs_mtx); 1378 goto fail; 1379 } 1380 } 1381 mutex_exit(&dn->dn_dbufs_mtx); 1382 1383 if (ibs && dn->dn_nlevels != 1) 1384 goto fail; 1385 1386 /* resize the old block */ 1387 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 1388 if (err == 0) 1389 dbuf_new_size(db, size, tx); 1390 else if (err != ENOENT) 1391 goto fail; 1392 1393 dnode_setdblksz(dn, size); 1394 dnode_setdirty(dn, tx); 1395 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 1396 if (ibs) { 1397 dn->dn_indblkshift = ibs; 1398 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 1399 } 1400 /* rele after we have fixed the blocksize in the dnode */ 1401 if (db) 1402 dbuf_rele(db, FTAG); 1403 1404 rw_exit(&dn->dn_struct_rwlock); 1405 return (0); 1406 1407fail: 1408 rw_exit(&dn->dn_struct_rwlock); 1409 return (SET_ERROR(ENOTSUP)); 1410} 1411 1412/* read-holding callers must not rely on the lock being continuously held */ 1413void 1414dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 1415{ 1416 uint64_t txgoff = tx->tx_txg & TXG_MASK; 1417 int epbs, new_nlevels; 1418 uint64_t sz; 1419 1420 ASSERT(blkid != DMU_BONUS_BLKID); 1421 1422 ASSERT(have_read ? 1423 RW_READ_HELD(&dn->dn_struct_rwlock) : 1424 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 1425 1426 /* 1427 * if we have a read-lock, check to see if we need to do any work 1428 * before upgrading to a write-lock. 1429 */ 1430 if (have_read) { 1431 if (blkid <= dn->dn_maxblkid) 1432 return; 1433 1434 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 1435 rw_exit(&dn->dn_struct_rwlock); 1436 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1437 } 1438 } 1439 1440 if (blkid <= dn->dn_maxblkid) 1441 goto out; 1442 1443 dn->dn_maxblkid = blkid; 1444 1445 /* 1446 * Compute the number of levels necessary to support the new maxblkid. 1447 */ 1448 new_nlevels = 1; 1449 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1450 for (sz = dn->dn_nblkptr; 1451 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 1452 new_nlevels++; 1453 1454 if (new_nlevels > dn->dn_nlevels) { 1455 int old_nlevels = dn->dn_nlevels; 1456 dmu_buf_impl_t *db; 1457 list_t *list; 1458 dbuf_dirty_record_t *new, *dr, *dr_next; 1459 1460 dn->dn_nlevels = new_nlevels; 1461 1462 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 1463 dn->dn_next_nlevels[txgoff] = new_nlevels; 1464 1465 /* dirty the left indirects */ 1466 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 1467 ASSERT(db != NULL); 1468 new = dbuf_dirty(db, tx); 1469 dbuf_rele(db, FTAG); 1470 1471 /* transfer the dirty records to the new indirect */ 1472 mutex_enter(&dn->dn_mtx); 1473 mutex_enter(&new->dt.di.dr_mtx); 1474 list = &dn->dn_dirty_records[txgoff]; 1475 for (dr = list_head(list); dr; dr = dr_next) { 1476 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 1477 if (dr->dr_dbuf->db_level != new_nlevels-1 && 1478 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 1479 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 1480 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 1481 list_remove(&dn->dn_dirty_records[txgoff], dr); 1482 list_insert_tail(&new->dt.di.dr_children, dr); 1483 dr->dr_parent = new; 1484 } 1485 } 1486 mutex_exit(&new->dt.di.dr_mtx); 1487 mutex_exit(&dn->dn_mtx); 1488 } 1489 1490out: 1491 if (have_read) 1492 rw_downgrade(&dn->dn_struct_rwlock); 1493} 1494 1495void 1496dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1497{ 1498 dmu_buf_impl_t *db; 1499 uint64_t blkoff, blkid, nblks; 1500 int blksz, blkshift, head, tail; 1501 int trunc = FALSE; 1502 int epbs; 1503 1504 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1505 blksz = dn->dn_datablksz; 1506 blkshift = dn->dn_datablkshift; 1507 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1508 1509 if (len == DMU_OBJECT_END) { 1510 len = UINT64_MAX - off; 1511 trunc = TRUE; 1512 } 1513 1514 /* 1515 * First, block align the region to free: 1516 */ 1517 if (ISP2(blksz)) { 1518 head = P2NPHASE(off, blksz); 1519 blkoff = P2PHASE(off, blksz); 1520 if ((off >> blkshift) > dn->dn_maxblkid) 1521 goto out; 1522 } else { 1523 ASSERT(dn->dn_maxblkid == 0); 1524 if (off == 0 && len >= blksz) { 1525 /* 1526 * Freeing the whole block; fast-track this request. 1527 * Note that we won't dirty any indirect blocks, 1528 * which is fine because we will be freeing the entire 1529 * file and thus all indirect blocks will be freed 1530 * by free_children(). 1531 */ 1532 blkid = 0; 1533 nblks = 1; 1534 goto done; 1535 } else if (off >= blksz) { 1536 /* Freeing past end-of-data */ 1537 goto out; 1538 } else { 1539 /* Freeing part of the block. */ 1540 head = blksz - off; 1541 ASSERT3U(head, >, 0); 1542 } 1543 blkoff = off; 1544 } 1545 /* zero out any partial block data at the start of the range */ 1546 if (head) { 1547 ASSERT3U(blkoff + head, ==, blksz); 1548 if (len < head) 1549 head = len; 1550 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1551 FTAG, &db) == 0) { 1552 caddr_t data; 1553 1554 /* don't dirty if it isn't on disk and isn't dirty */ 1555 if (db->db_last_dirty || 1556 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1557 rw_exit(&dn->dn_struct_rwlock); 1558 dmu_buf_will_dirty(&db->db, tx); 1559 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1560 data = db->db.db_data; 1561 bzero(data + blkoff, head); 1562 } 1563 dbuf_rele(db, FTAG); 1564 } 1565 off += head; 1566 len -= head; 1567 } 1568 1569 /* If the range was less than one block, we're done */ 1570 if (len == 0) 1571 goto out; 1572 1573 /* If the remaining range is past end of file, we're done */ 1574 if ((off >> blkshift) > dn->dn_maxblkid) 1575 goto out; 1576 1577 ASSERT(ISP2(blksz)); 1578 if (trunc) 1579 tail = 0; 1580 else 1581 tail = P2PHASE(len, blksz); 1582 1583 ASSERT0(P2PHASE(off, blksz)); 1584 /* zero out any partial block data at the end of the range */ 1585 if (tail) { 1586 if (len < tail) 1587 tail = len; 1588 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1589 TRUE, FTAG, &db) == 0) { 1590 /* don't dirty if not on disk and not 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 bzero(db->db.db_data, tail); 1597 } 1598 dbuf_rele(db, FTAG); 1599 } 1600 len -= tail; 1601 } 1602 1603 /* If the range did not include a full block, we are done */ 1604 if (len == 0) 1605 goto out; 1606 1607 ASSERT(IS_P2ALIGNED(off, blksz)); 1608 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1609 blkid = off >> blkshift; 1610 nblks = len >> blkshift; 1611 if (trunc) 1612 nblks += 1; 1613 1614 /* 1615 * Dirty the first and last indirect blocks, as they (and/or their 1616 * parents) will need to be written out if they were only 1617 * partially freed. Interior indirect blocks will be themselves freed, 1618 * by free_children(), so they need not be dirtied. Note that these 1619 * interior blocks have already been prefetched by dmu_tx_hold_free(). 1620 */ 1621 if (dn->dn_nlevels > 1) { 1622 uint64_t first, last; 1623 1624 first = blkid >> epbs; 1625 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1626 dmu_buf_will_dirty(&db->db, tx); 1627 dbuf_rele(db, FTAG); 1628 } 1629 if (trunc) 1630 last = dn->dn_maxblkid >> epbs; 1631 else 1632 last = (blkid + nblks - 1) >> epbs; 1633 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1634 dmu_buf_will_dirty(&db->db, tx); 1635 dbuf_rele(db, FTAG); 1636 } 1637 } 1638 1639done: 1640 /* 1641 * Add this range to the dnode range list. 1642 * We will finish up this free operation in the syncing phase. 1643 */ 1644 mutex_enter(&dn->dn_mtx); 1645 int txgoff = tx->tx_txg & TXG_MASK; 1646 if (dn->dn_free_ranges[txgoff] == NULL) { 1647 dn->dn_free_ranges[txgoff] = 1648 range_tree_create(NULL, NULL, &dn->dn_mtx); 1649 } 1650 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 1651 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 1652 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1653 blkid, nblks, tx->tx_txg); 1654 mutex_exit(&dn->dn_mtx); 1655 1656 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1657 dnode_setdirty(dn, tx); 1658out: 1659 1660 rw_exit(&dn->dn_struct_rwlock); 1661} 1662 1663static boolean_t 1664dnode_spill_freed(dnode_t *dn) 1665{ 1666 int i; 1667 1668 mutex_enter(&dn->dn_mtx); 1669 for (i = 0; i < TXG_SIZE; i++) { 1670 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1671 break; 1672 } 1673 mutex_exit(&dn->dn_mtx); 1674 return (i < TXG_SIZE); 1675} 1676 1677/* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1678uint64_t 1679dnode_block_freed(dnode_t *dn, uint64_t blkid) 1680{ 1681 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1682 int i; 1683 1684 if (blkid == DMU_BONUS_BLKID) 1685 return (FALSE); 1686 1687 /* 1688 * If we're in the process of opening the pool, dp will not be 1689 * set yet, but there shouldn't be anything dirty. 1690 */ 1691 if (dp == NULL) 1692 return (FALSE); 1693 1694 if (dn->dn_free_txg) 1695 return (TRUE); 1696 1697 if (blkid == DMU_SPILL_BLKID) 1698 return (dnode_spill_freed(dn)); 1699 1700 mutex_enter(&dn->dn_mtx); 1701 for (i = 0; i < TXG_SIZE; i++) { 1702 if (dn->dn_free_ranges[i] != NULL && 1703 range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 1704 break; 1705 } 1706 mutex_exit(&dn->dn_mtx); 1707 return (i < TXG_SIZE); 1708} 1709 1710/* call from syncing context when we actually write/free space for this dnode */ 1711void 1712dnode_diduse_space(dnode_t *dn, int64_t delta) 1713{ 1714 uint64_t space; 1715 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1716 dn, dn->dn_phys, 1717 (u_longlong_t)dn->dn_phys->dn_used, 1718 (longlong_t)delta); 1719 1720 mutex_enter(&dn->dn_mtx); 1721 space = DN_USED_BYTES(dn->dn_phys); 1722 if (delta > 0) { 1723 ASSERT3U(space + delta, >=, space); /* no overflow */ 1724 } else { 1725 ASSERT3U(space, >=, -delta); /* no underflow */ 1726 } 1727 space += delta; 1728 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1729 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1730 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 1731 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1732 } else { 1733 dn->dn_phys->dn_used = space; 1734 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1735 } 1736 mutex_exit(&dn->dn_mtx); 1737} 1738 1739/* 1740 * Call when we think we're going to write/free space in open context to track 1741 * the amount of memory in use by the currently open txg. 1742 */ 1743void 1744dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1745{ 1746 objset_t *os = dn->dn_objset; 1747 dsl_dataset_t *ds = os->os_dsl_dataset; 1748 int64_t aspace = spa_get_asize(os->os_spa, space); 1749 1750 if (ds != NULL) { 1751 dsl_dir_willuse_space(ds->ds_dir, aspace, tx); 1752 dsl_pool_dirty_space(dmu_tx_pool(tx), space, tx); 1753 } 1754 1755 dmu_tx_willuse_space(tx, aspace); 1756} 1757 1758/* 1759 * Scans a block at the indicated "level" looking for a hole or data, 1760 * depending on 'flags'. 1761 * 1762 * If level > 0, then we are scanning an indirect block looking at its 1763 * pointers. If level == 0, then we are looking at a block of dnodes. 1764 * 1765 * If we don't find what we are looking for in the block, we return ESRCH. 1766 * Otherwise, return with *offset pointing to the beginning (if searching 1767 * forwards) or end (if searching backwards) of the range covered by the 1768 * block pointer we matched on (or dnode). 1769 * 1770 * The basic search algorithm used below by dnode_next_offset() is to 1771 * use this function to search up the block tree (widen the search) until 1772 * we find something (i.e., we don't return ESRCH) and then search back 1773 * down the tree (narrow the search) until we reach our original search 1774 * level. 1775 */ 1776static int 1777dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1778 int lvl, uint64_t blkfill, uint64_t txg) 1779{ 1780 dmu_buf_impl_t *db = NULL; 1781 void *data = NULL; 1782 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1783 uint64_t epb = 1ULL << epbs; 1784 uint64_t minfill, maxfill; 1785 boolean_t hole; 1786 int i, inc, error, span; 1787 1788 dprintf("probing object %llu offset %llx level %d of %u\n", 1789 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1790 1791 hole = ((flags & DNODE_FIND_HOLE) != 0); 1792 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1793 ASSERT(txg == 0 || !hole); 1794 1795 if (lvl == dn->dn_phys->dn_nlevels) { 1796 error = 0; 1797 epb = dn->dn_phys->dn_nblkptr; 1798 data = dn->dn_phys->dn_blkptr; 1799 } else { 1800 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1801 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1802 if (error) { 1803 if (error != ENOENT) 1804 return (error); 1805 if (hole) 1806 return (0); 1807 /* 1808 * This can only happen when we are searching up 1809 * the block tree for data. We don't really need to 1810 * adjust the offset, as we will just end up looking 1811 * at the pointer to this block in its parent, and its 1812 * going to be unallocated, so we will skip over it. 1813 */ 1814 return (SET_ERROR(ESRCH)); 1815 } 1816 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1817 if (error) { 1818 dbuf_rele(db, FTAG); 1819 return (error); 1820 } 1821 data = db->db.db_data; 1822 } 1823 1824 1825 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 1826 db->db_blkptr->blk_birth <= txg || 1827 BP_IS_HOLE(db->db_blkptr))) { 1828 /* 1829 * This can only happen when we are searching up the tree 1830 * and these conditions mean that we need to keep climbing. 1831 */ 1832 error = SET_ERROR(ESRCH); 1833 } else if (lvl == 0) { 1834 dnode_phys_t *dnp = data; 1835 span = DNODE_SHIFT; 1836 ASSERT(dn->dn_type == DMU_OT_DNODE); 1837 1838 for (i = (*offset >> span) & (blkfill - 1); 1839 i >= 0 && i < blkfill; i += inc) { 1840 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1841 break; 1842 *offset += (1ULL << span) * inc; 1843 } 1844 if (i < 0 || i == blkfill) 1845 error = SET_ERROR(ESRCH); 1846 } else { 1847 blkptr_t *bp = data; 1848 uint64_t start = *offset; 1849 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1850 minfill = 0; 1851 maxfill = blkfill << ((lvl - 1) * epbs); 1852 1853 if (hole) 1854 maxfill--; 1855 else 1856 minfill++; 1857 1858 *offset = *offset >> span; 1859 for (i = BF64_GET(*offset, 0, epbs); 1860 i >= 0 && i < epb; i += inc) { 1861 if (BP_GET_FILL(&bp[i]) >= minfill && 1862 BP_GET_FILL(&bp[i]) <= maxfill && 1863 (hole || bp[i].blk_birth > txg)) 1864 break; 1865 if (inc > 0 || *offset > 0) 1866 *offset += inc; 1867 } 1868 *offset = *offset << span; 1869 if (inc < 0) { 1870 /* traversing backwards; position offset at the end */ 1871 ASSERT3U(*offset, <=, start); 1872 *offset = MIN(*offset + (1ULL << span) - 1, start); 1873 } else if (*offset < start) { 1874 *offset = start; 1875 } 1876 if (i < 0 || i >= epb) 1877 error = SET_ERROR(ESRCH); 1878 } 1879 1880 if (db) 1881 dbuf_rele(db, FTAG); 1882 1883 return (error); 1884} 1885 1886/* 1887 * Find the next hole, data, or sparse region at or after *offset. 1888 * The value 'blkfill' tells us how many items we expect to find 1889 * in an L0 data block; this value is 1 for normal objects, 1890 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1891 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1892 * 1893 * Examples: 1894 * 1895 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1896 * Finds the next/previous hole/data in a file. 1897 * Used in dmu_offset_next(). 1898 * 1899 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1900 * Finds the next free/allocated dnode an objset's meta-dnode. 1901 * Only finds objects that have new contents since txg (ie. 1902 * bonus buffer changes and content removal are ignored). 1903 * Used in dmu_object_next(). 1904 * 1905 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1906 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1907 * Used in dmu_object_alloc(). 1908 */ 1909int 1910dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1911 int minlvl, uint64_t blkfill, uint64_t txg) 1912{ 1913 uint64_t initial_offset = *offset; 1914 int lvl, maxlvl; 1915 int error = 0; 1916 1917 if (!(flags & DNODE_FIND_HAVELOCK)) 1918 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1919 1920 if (dn->dn_phys->dn_nlevels == 0) { 1921 error = SET_ERROR(ESRCH); 1922 goto out; 1923 } 1924 1925 if (dn->dn_datablkshift == 0) { 1926 if (*offset < dn->dn_datablksz) { 1927 if (flags & DNODE_FIND_HOLE) 1928 *offset = dn->dn_datablksz; 1929 } else { 1930 error = SET_ERROR(ESRCH); 1931 } 1932 goto out; 1933 } 1934 1935 maxlvl = dn->dn_phys->dn_nlevels; 1936 1937 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1938 error = dnode_next_offset_level(dn, 1939 flags, offset, lvl, blkfill, txg); 1940 if (error != ESRCH) 1941 break; 1942 } 1943 1944 while (error == 0 && --lvl >= minlvl) { 1945 error = dnode_next_offset_level(dn, 1946 flags, offset, lvl, blkfill, txg); 1947 } 1948 1949 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1950 initial_offset < *offset : initial_offset > *offset)) 1951 error = SET_ERROR(ESRCH); 1952out: 1953 if (!(flags & DNODE_FIND_HAVELOCK)) 1954 rw_exit(&dn->dn_struct_rwlock); 1955 1956 return (error); 1957} 1958