1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2012, 2020 by Delphix. All rights reserved. 25 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 26 */ 27 28 #include <sys/zfs_context.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/dmu.h> 32 #include <sys/dmu_impl.h> 33 #include <sys/dmu_tx.h> 34 #include <sys/dmu_objset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_dataset.h> 37 #include <sys/spa.h> 38 #include <sys/zio.h> 39 #include <sys/dmu_zfetch.h> 40 #include <sys/range_tree.h> 41 #include <sys/trace_zfs.h> 42 #include <sys/zfs_project.h> 43 44 dnode_stats_t dnode_stats = { 45 { "dnode_hold_dbuf_hold", KSTAT_DATA_UINT64 }, 46 { "dnode_hold_dbuf_read", KSTAT_DATA_UINT64 }, 47 { "dnode_hold_alloc_hits", KSTAT_DATA_UINT64 }, 48 { "dnode_hold_alloc_misses", KSTAT_DATA_UINT64 }, 49 { "dnode_hold_alloc_interior", KSTAT_DATA_UINT64 }, 50 { "dnode_hold_alloc_lock_retry", KSTAT_DATA_UINT64 }, 51 { "dnode_hold_alloc_lock_misses", KSTAT_DATA_UINT64 }, 52 { "dnode_hold_alloc_type_none", KSTAT_DATA_UINT64 }, 53 { "dnode_hold_free_hits", KSTAT_DATA_UINT64 }, 54 { "dnode_hold_free_misses", KSTAT_DATA_UINT64 }, 55 { "dnode_hold_free_lock_misses", KSTAT_DATA_UINT64 }, 56 { "dnode_hold_free_lock_retry", KSTAT_DATA_UINT64 }, 57 { "dnode_hold_free_overflow", KSTAT_DATA_UINT64 }, 58 { "dnode_hold_free_refcount", KSTAT_DATA_UINT64 }, 59 { "dnode_free_interior_lock_retry", KSTAT_DATA_UINT64 }, 60 { "dnode_allocate", KSTAT_DATA_UINT64 }, 61 { "dnode_reallocate", KSTAT_DATA_UINT64 }, 62 { "dnode_buf_evict", KSTAT_DATA_UINT64 }, 63 { "dnode_alloc_next_chunk", KSTAT_DATA_UINT64 }, 64 { "dnode_alloc_race", KSTAT_DATA_UINT64 }, 65 { "dnode_alloc_next_block", KSTAT_DATA_UINT64 }, 66 { "dnode_move_invalid", KSTAT_DATA_UINT64 }, 67 { "dnode_move_recheck1", KSTAT_DATA_UINT64 }, 68 { "dnode_move_recheck2", KSTAT_DATA_UINT64 }, 69 { "dnode_move_special", KSTAT_DATA_UINT64 }, 70 { "dnode_move_handle", KSTAT_DATA_UINT64 }, 71 { "dnode_move_rwlock", KSTAT_DATA_UINT64 }, 72 { "dnode_move_active", KSTAT_DATA_UINT64 }, 73 }; 74 75 dnode_sums_t dnode_sums; 76 77 static kstat_t *dnode_ksp; 78 static kmem_cache_t *dnode_cache; 79 80 static dnode_phys_t dnode_phys_zero __maybe_unused; 81 82 int zfs_default_bs = SPA_MINBLOCKSHIFT; 83 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 84 85 #ifdef _KERNEL 86 static kmem_cbrc_t dnode_move(void *, void *, size_t, void *); 87 #endif /* _KERNEL */ 88 89 static char * 90 rt_name(dnode_t *dn, const char *name) 91 { 92 struct objset *os = dn->dn_objset; 93 94 return (kmem_asprintf("{spa=%s objset=%llu obj=%llu %s}", 95 spa_name(os->os_spa), 96 (u_longlong_t)(os->os_dsl_dataset ? 97 os->os_dsl_dataset->ds_object : DMU_META_OBJSET), 98 (u_longlong_t)dn->dn_object, 99 name)); 100 } 101 102 static int 103 dbuf_compare(const void *x1, const void *x2) 104 { 105 const dmu_buf_impl_t *d1 = x1; 106 const dmu_buf_impl_t *d2 = x2; 107 108 int cmp = TREE_CMP(d1->db_level, d2->db_level); 109 if (likely(cmp)) 110 return (cmp); 111 112 cmp = TREE_CMP(d1->db_blkid, d2->db_blkid); 113 if (likely(cmp)) 114 return (cmp); 115 116 if (d1->db_state == DB_MARKER) { 117 ASSERT3S(d2->db_state, !=, DB_MARKER); 118 return (TREE_PCMP(d1->db_parent, d2)); 119 } else if (d2->db_state == DB_MARKER) { 120 ASSERT3S(d1->db_state, !=, DB_MARKER); 121 return (TREE_PCMP(d1, d2->db_parent)); 122 } 123 124 if (d1->db_state == DB_SEARCH) { 125 ASSERT3S(d2->db_state, !=, DB_SEARCH); 126 return (-1); 127 } else if (d2->db_state == DB_SEARCH) { 128 ASSERT3S(d1->db_state, !=, DB_SEARCH); 129 return (1); 130 } 131 132 return (TREE_PCMP(d1, d2)); 133 } 134 135 static int 136 dnode_cons(void *arg, void *unused, int kmflag) 137 { 138 (void) unused, (void) kmflag; 139 dnode_t *dn = arg; 140 141 rw_init(&dn->dn_struct_rwlock, NULL, RW_NOLOCKDEP, NULL); 142 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 143 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 144 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 145 cv_init(&dn->dn_nodnholds, NULL, CV_DEFAULT, NULL); 146 147 /* 148 * Every dbuf has a reference, and dropping a tracked reference is 149 * O(number of references), so don't track dn_holds. 150 */ 151 zfs_refcount_create_untracked(&dn->dn_holds); 152 zfs_refcount_create(&dn->dn_tx_holds); 153 list_link_init(&dn->dn_link); 154 155 memset(dn->dn_next_type, 0, sizeof (dn->dn_next_type)); 156 memset(dn->dn_next_nblkptr, 0, sizeof (dn->dn_next_nblkptr)); 157 memset(dn->dn_next_nlevels, 0, sizeof (dn->dn_next_nlevels)); 158 memset(dn->dn_next_indblkshift, 0, sizeof (dn->dn_next_indblkshift)); 159 memset(dn->dn_next_bonustype, 0, sizeof (dn->dn_next_bonustype)); 160 memset(dn->dn_rm_spillblk, 0, sizeof (dn->dn_rm_spillblk)); 161 memset(dn->dn_next_bonuslen, 0, sizeof (dn->dn_next_bonuslen)); 162 memset(dn->dn_next_blksz, 0, sizeof (dn->dn_next_blksz)); 163 memset(dn->dn_next_maxblkid, 0, sizeof (dn->dn_next_maxblkid)); 164 165 for (int i = 0; i < TXG_SIZE; i++) { 166 multilist_link_init(&dn->dn_dirty_link[i]); 167 dn->dn_free_ranges[i] = NULL; 168 list_create(&dn->dn_dirty_records[i], 169 sizeof (dbuf_dirty_record_t), 170 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 171 } 172 173 dn->dn_allocated_txg = 0; 174 dn->dn_free_txg = 0; 175 dn->dn_assigned_txg = 0; 176 dn->dn_dirtycnt = 0; 177 dn->dn_bonus = NULL; 178 dn->dn_have_spill = B_FALSE; 179 dn->dn_zio = NULL; 180 dn->dn_oldused = 0; 181 dn->dn_oldflags = 0; 182 dn->dn_olduid = 0; 183 dn->dn_oldgid = 0; 184 dn->dn_oldprojid = ZFS_DEFAULT_PROJID; 185 dn->dn_newuid = 0; 186 dn->dn_newgid = 0; 187 dn->dn_newprojid = ZFS_DEFAULT_PROJID; 188 dn->dn_id_flags = 0; 189 190 dn->dn_dbufs_count = 0; 191 avl_create(&dn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 192 offsetof(dmu_buf_impl_t, db_link)); 193 194 dn->dn_moved = 0; 195 return (0); 196 } 197 198 static void 199 dnode_dest(void *arg, void *unused) 200 { 201 (void) unused; 202 dnode_t *dn = arg; 203 204 rw_destroy(&dn->dn_struct_rwlock); 205 mutex_destroy(&dn->dn_mtx); 206 mutex_destroy(&dn->dn_dbufs_mtx); 207 cv_destroy(&dn->dn_notxholds); 208 cv_destroy(&dn->dn_nodnholds); 209 zfs_refcount_destroy(&dn->dn_holds); 210 zfs_refcount_destroy(&dn->dn_tx_holds); 211 ASSERT(!list_link_active(&dn->dn_link)); 212 213 for (int i = 0; i < TXG_SIZE; i++) { 214 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i])); 215 ASSERT0P(dn->dn_free_ranges[i]); 216 list_destroy(&dn->dn_dirty_records[i]); 217 ASSERT0(dn->dn_next_nblkptr[i]); 218 ASSERT0(dn->dn_next_nlevels[i]); 219 ASSERT0(dn->dn_next_indblkshift[i]); 220 ASSERT0(dn->dn_next_bonustype[i]); 221 ASSERT0(dn->dn_rm_spillblk[i]); 222 ASSERT0(dn->dn_next_bonuslen[i]); 223 ASSERT0(dn->dn_next_blksz[i]); 224 ASSERT0(dn->dn_next_maxblkid[i]); 225 } 226 227 ASSERT0(dn->dn_allocated_txg); 228 ASSERT0(dn->dn_free_txg); 229 ASSERT0(dn->dn_assigned_txg); 230 ASSERT0(dn->dn_dirtycnt); 231 ASSERT0P(dn->dn_bonus); 232 ASSERT(!dn->dn_have_spill); 233 ASSERT0P(dn->dn_zio); 234 ASSERT0(dn->dn_oldused); 235 ASSERT0(dn->dn_oldflags); 236 ASSERT0(dn->dn_olduid); 237 ASSERT0(dn->dn_oldgid); 238 ASSERT0(dn->dn_oldprojid); 239 ASSERT0(dn->dn_newuid); 240 ASSERT0(dn->dn_newgid); 241 ASSERT0(dn->dn_newprojid); 242 ASSERT0(dn->dn_id_flags); 243 244 ASSERT0(dn->dn_dbufs_count); 245 avl_destroy(&dn->dn_dbufs); 246 } 247 248 static int 249 dnode_kstats_update(kstat_t *ksp, int rw) 250 { 251 dnode_stats_t *ds = ksp->ks_data; 252 253 if (rw == KSTAT_WRITE) 254 return (EACCES); 255 ds->dnode_hold_dbuf_hold.value.ui64 = 256 wmsum_value(&dnode_sums.dnode_hold_dbuf_hold); 257 ds->dnode_hold_dbuf_read.value.ui64 = 258 wmsum_value(&dnode_sums.dnode_hold_dbuf_read); 259 ds->dnode_hold_alloc_hits.value.ui64 = 260 wmsum_value(&dnode_sums.dnode_hold_alloc_hits); 261 ds->dnode_hold_alloc_misses.value.ui64 = 262 wmsum_value(&dnode_sums.dnode_hold_alloc_misses); 263 ds->dnode_hold_alloc_interior.value.ui64 = 264 wmsum_value(&dnode_sums.dnode_hold_alloc_interior); 265 ds->dnode_hold_alloc_lock_retry.value.ui64 = 266 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_retry); 267 ds->dnode_hold_alloc_lock_misses.value.ui64 = 268 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_misses); 269 ds->dnode_hold_alloc_type_none.value.ui64 = 270 wmsum_value(&dnode_sums.dnode_hold_alloc_type_none); 271 ds->dnode_hold_free_hits.value.ui64 = 272 wmsum_value(&dnode_sums.dnode_hold_free_hits); 273 ds->dnode_hold_free_misses.value.ui64 = 274 wmsum_value(&dnode_sums.dnode_hold_free_misses); 275 ds->dnode_hold_free_lock_misses.value.ui64 = 276 wmsum_value(&dnode_sums.dnode_hold_free_lock_misses); 277 ds->dnode_hold_free_lock_retry.value.ui64 = 278 wmsum_value(&dnode_sums.dnode_hold_free_lock_retry); 279 ds->dnode_hold_free_refcount.value.ui64 = 280 wmsum_value(&dnode_sums.dnode_hold_free_refcount); 281 ds->dnode_hold_free_overflow.value.ui64 = 282 wmsum_value(&dnode_sums.dnode_hold_free_overflow); 283 ds->dnode_free_interior_lock_retry.value.ui64 = 284 wmsum_value(&dnode_sums.dnode_free_interior_lock_retry); 285 ds->dnode_allocate.value.ui64 = 286 wmsum_value(&dnode_sums.dnode_allocate); 287 ds->dnode_reallocate.value.ui64 = 288 wmsum_value(&dnode_sums.dnode_reallocate); 289 ds->dnode_buf_evict.value.ui64 = 290 wmsum_value(&dnode_sums.dnode_buf_evict); 291 ds->dnode_alloc_next_chunk.value.ui64 = 292 wmsum_value(&dnode_sums.dnode_alloc_next_chunk); 293 ds->dnode_alloc_race.value.ui64 = 294 wmsum_value(&dnode_sums.dnode_alloc_race); 295 ds->dnode_alloc_next_block.value.ui64 = 296 wmsum_value(&dnode_sums.dnode_alloc_next_block); 297 ds->dnode_move_invalid.value.ui64 = 298 wmsum_value(&dnode_sums.dnode_move_invalid); 299 ds->dnode_move_recheck1.value.ui64 = 300 wmsum_value(&dnode_sums.dnode_move_recheck1); 301 ds->dnode_move_recheck2.value.ui64 = 302 wmsum_value(&dnode_sums.dnode_move_recheck2); 303 ds->dnode_move_special.value.ui64 = 304 wmsum_value(&dnode_sums.dnode_move_special); 305 ds->dnode_move_handle.value.ui64 = 306 wmsum_value(&dnode_sums.dnode_move_handle); 307 ds->dnode_move_rwlock.value.ui64 = 308 wmsum_value(&dnode_sums.dnode_move_rwlock); 309 ds->dnode_move_active.value.ui64 = 310 wmsum_value(&dnode_sums.dnode_move_active); 311 return (0); 312 } 313 314 void 315 dnode_init(void) 316 { 317 ASSERT0P(dnode_cache); 318 dnode_cache = kmem_cache_create("dnode_t", sizeof (dnode_t), 319 0, dnode_cons, dnode_dest, NULL, NULL, NULL, KMC_RECLAIMABLE); 320 kmem_cache_set_move(dnode_cache, dnode_move); 321 322 wmsum_init(&dnode_sums.dnode_hold_dbuf_hold, 0); 323 wmsum_init(&dnode_sums.dnode_hold_dbuf_read, 0); 324 wmsum_init(&dnode_sums.dnode_hold_alloc_hits, 0); 325 wmsum_init(&dnode_sums.dnode_hold_alloc_misses, 0); 326 wmsum_init(&dnode_sums.dnode_hold_alloc_interior, 0); 327 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_retry, 0); 328 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_misses, 0); 329 wmsum_init(&dnode_sums.dnode_hold_alloc_type_none, 0); 330 wmsum_init(&dnode_sums.dnode_hold_free_hits, 0); 331 wmsum_init(&dnode_sums.dnode_hold_free_misses, 0); 332 wmsum_init(&dnode_sums.dnode_hold_free_lock_misses, 0); 333 wmsum_init(&dnode_sums.dnode_hold_free_lock_retry, 0); 334 wmsum_init(&dnode_sums.dnode_hold_free_refcount, 0); 335 wmsum_init(&dnode_sums.dnode_hold_free_overflow, 0); 336 wmsum_init(&dnode_sums.dnode_free_interior_lock_retry, 0); 337 wmsum_init(&dnode_sums.dnode_allocate, 0); 338 wmsum_init(&dnode_sums.dnode_reallocate, 0); 339 wmsum_init(&dnode_sums.dnode_buf_evict, 0); 340 wmsum_init(&dnode_sums.dnode_alloc_next_chunk, 0); 341 wmsum_init(&dnode_sums.dnode_alloc_race, 0); 342 wmsum_init(&dnode_sums.dnode_alloc_next_block, 0); 343 wmsum_init(&dnode_sums.dnode_move_invalid, 0); 344 wmsum_init(&dnode_sums.dnode_move_recheck1, 0); 345 wmsum_init(&dnode_sums.dnode_move_recheck2, 0); 346 wmsum_init(&dnode_sums.dnode_move_special, 0); 347 wmsum_init(&dnode_sums.dnode_move_handle, 0); 348 wmsum_init(&dnode_sums.dnode_move_rwlock, 0); 349 wmsum_init(&dnode_sums.dnode_move_active, 0); 350 351 dnode_ksp = kstat_create("zfs", 0, "dnodestats", "misc", 352 KSTAT_TYPE_NAMED, sizeof (dnode_stats) / sizeof (kstat_named_t), 353 KSTAT_FLAG_VIRTUAL); 354 if (dnode_ksp != NULL) { 355 dnode_ksp->ks_data = &dnode_stats; 356 dnode_ksp->ks_update = dnode_kstats_update; 357 kstat_install(dnode_ksp); 358 } 359 } 360 361 void 362 dnode_fini(void) 363 { 364 if (dnode_ksp != NULL) { 365 kstat_delete(dnode_ksp); 366 dnode_ksp = NULL; 367 } 368 369 wmsum_fini(&dnode_sums.dnode_hold_dbuf_hold); 370 wmsum_fini(&dnode_sums.dnode_hold_dbuf_read); 371 wmsum_fini(&dnode_sums.dnode_hold_alloc_hits); 372 wmsum_fini(&dnode_sums.dnode_hold_alloc_misses); 373 wmsum_fini(&dnode_sums.dnode_hold_alloc_interior); 374 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_retry); 375 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_misses); 376 wmsum_fini(&dnode_sums.dnode_hold_alloc_type_none); 377 wmsum_fini(&dnode_sums.dnode_hold_free_hits); 378 wmsum_fini(&dnode_sums.dnode_hold_free_misses); 379 wmsum_fini(&dnode_sums.dnode_hold_free_lock_misses); 380 wmsum_fini(&dnode_sums.dnode_hold_free_lock_retry); 381 wmsum_fini(&dnode_sums.dnode_hold_free_refcount); 382 wmsum_fini(&dnode_sums.dnode_hold_free_overflow); 383 wmsum_fini(&dnode_sums.dnode_free_interior_lock_retry); 384 wmsum_fini(&dnode_sums.dnode_allocate); 385 wmsum_fini(&dnode_sums.dnode_reallocate); 386 wmsum_fini(&dnode_sums.dnode_buf_evict); 387 wmsum_fini(&dnode_sums.dnode_alloc_next_chunk); 388 wmsum_fini(&dnode_sums.dnode_alloc_race); 389 wmsum_fini(&dnode_sums.dnode_alloc_next_block); 390 wmsum_fini(&dnode_sums.dnode_move_invalid); 391 wmsum_fini(&dnode_sums.dnode_move_recheck1); 392 wmsum_fini(&dnode_sums.dnode_move_recheck2); 393 wmsum_fini(&dnode_sums.dnode_move_special); 394 wmsum_fini(&dnode_sums.dnode_move_handle); 395 wmsum_fini(&dnode_sums.dnode_move_rwlock); 396 wmsum_fini(&dnode_sums.dnode_move_active); 397 398 kmem_cache_destroy(dnode_cache); 399 dnode_cache = NULL; 400 } 401 402 403 #ifdef ZFS_DEBUG 404 void 405 dnode_verify(dnode_t *dn) 406 { 407 int drop_struct_lock = FALSE; 408 409 ASSERT(dn->dn_phys); 410 ASSERT(dn->dn_objset); 411 ASSERT(dn->dn_handle->dnh_dnode == dn); 412 413 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 414 415 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 416 return; 417 418 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 419 rw_enter(&dn->dn_struct_rwlock, RW_READER); 420 drop_struct_lock = TRUE; 421 } 422 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 423 int i; 424 int max_bonuslen = DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots); 425 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 426 if (dn->dn_datablkshift) { 427 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 428 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 429 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 430 } 431 ASSERT3U(dn->dn_nlevels, <=, 30); 432 ASSERT(DMU_OT_IS_VALID(dn->dn_type)); 433 ASSERT3U(dn->dn_nblkptr, >=, 1); 434 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 435 ASSERT3U(dn->dn_bonuslen, <=, max_bonuslen); 436 ASSERT3U(dn->dn_datablksz, ==, 437 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 438 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 439 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 440 dn->dn_bonuslen, <=, max_bonuslen); 441 for (i = 0; i < TXG_SIZE; i++) { 442 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 443 } 444 } 445 if (dn->dn_phys->dn_type != DMU_OT_NONE) 446 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 447 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 448 if (dn->dn_dbuf != NULL) { 449 ASSERT3P(dn->dn_phys, ==, 450 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 451 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 452 } 453 if (drop_struct_lock) 454 rw_exit(&dn->dn_struct_rwlock); 455 } 456 #endif 457 458 void 459 dnode_byteswap(dnode_phys_t *dnp) 460 { 461 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 462 int i; 463 464 if (dnp->dn_type == DMU_OT_NONE) { 465 memset(dnp, 0, sizeof (dnode_phys_t)); 466 return; 467 } 468 469 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 470 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 471 dnp->dn_extra_slots = BSWAP_8(dnp->dn_extra_slots); 472 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 473 dnp->dn_used = BSWAP_64(dnp->dn_used); 474 475 /* 476 * dn_nblkptr is only one byte, so it's OK to read it in either 477 * byte order. We can't read dn_bouslen. 478 */ 479 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 480 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 481 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 482 buf64[i] = BSWAP_64(buf64[i]); 483 484 /* 485 * OK to check dn_bonuslen for zero, because it won't matter if 486 * we have the wrong byte order. This is necessary because the 487 * dnode dnode is smaller than a regular dnode. 488 */ 489 if (dnp->dn_bonuslen != 0) { 490 dmu_object_byteswap_t byteswap; 491 ASSERT(DMU_OT_IS_VALID(dnp->dn_bonustype)); 492 byteswap = DMU_OT_BYTESWAP(dnp->dn_bonustype); 493 dmu_ot_byteswap[byteswap].ob_func(DN_BONUS(dnp), 494 DN_MAX_BONUS_LEN(dnp)); 495 } 496 497 /* Swap SPILL block if we have one */ 498 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 499 byteswap_uint64_array(DN_SPILL_BLKPTR(dnp), sizeof (blkptr_t)); 500 } 501 502 void 503 dnode_buf_byteswap(void *vbuf, size_t size) 504 { 505 int i = 0; 506 507 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 508 ASSERT0((size & (sizeof (dnode_phys_t)-1))); 509 510 while (i < size) { 511 dnode_phys_t *dnp = (void *)(((char *)vbuf) + i); 512 dnode_byteswap(dnp); 513 514 i += DNODE_MIN_SIZE; 515 if (dnp->dn_type != DMU_OT_NONE) 516 i += dnp->dn_extra_slots * DNODE_MIN_SIZE; 517 } 518 } 519 520 void 521 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 522 { 523 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 524 525 dnode_setdirty(dn, tx); 526 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 527 ASSERT3U(newsize, <=, DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) - 528 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 529 530 if (newsize < dn->dn_bonuslen) { 531 /* clear any data after the end of the new size */ 532 size_t diff = dn->dn_bonuslen - newsize; 533 char *data_end = ((char *)dn->dn_bonus->db.db_data) + newsize; 534 memset(data_end, 0, diff); 535 } 536 537 dn->dn_bonuslen = newsize; 538 if (newsize == 0) 539 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 540 else 541 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 542 rw_exit(&dn->dn_struct_rwlock); 543 } 544 545 void 546 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 547 { 548 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 549 dnode_setdirty(dn, tx); 550 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 551 dn->dn_bonustype = newtype; 552 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 553 rw_exit(&dn->dn_struct_rwlock); 554 } 555 556 void 557 dnode_set_storage_type(dnode_t *dn, dmu_object_type_t newtype) 558 { 559 /* 560 * This is not in the dnode_phys, but it should be, and perhaps one day 561 * will. For now we require it be set after taking a hold. 562 */ 563 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 564 dn->dn_storage_type = newtype; 565 } 566 567 void 568 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 569 { 570 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 571 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 572 dnode_setdirty(dn, tx); 573 dn->dn_rm_spillblk[tx->tx_txg & TXG_MASK] = DN_KILL_SPILLBLK; 574 dn->dn_have_spill = B_FALSE; 575 } 576 577 static void 578 dnode_setdblksz(dnode_t *dn, int size) 579 { 580 ASSERT0(P2PHASE(size, SPA_MINBLOCKSIZE)); 581 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 582 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 583 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 584 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 585 dn->dn_datablksz = size; 586 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 587 dn->dn_datablkshift = ISP2(size) ? highbit64(size - 1) : 0; 588 } 589 590 static dnode_t * 591 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 592 uint64_t object, dnode_handle_t *dnh) 593 { 594 dnode_t *dn; 595 596 dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 597 dn->dn_moved = 0; 598 599 /* 600 * Defer setting dn_objset until the dnode is ready to be a candidate 601 * for the dnode_move() callback. 602 */ 603 dn->dn_object = object; 604 dn->dn_dbuf = db; 605 dn->dn_handle = dnh; 606 dn->dn_phys = dnp; 607 608 if (dnp->dn_datablkszsec) { 609 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 610 } else { 611 dn->dn_datablksz = 0; 612 dn->dn_datablkszsec = 0; 613 dn->dn_datablkshift = 0; 614 } 615 dn->dn_indblkshift = dnp->dn_indblkshift; 616 dn->dn_nlevels = dnp->dn_nlevels; 617 dn->dn_type = dnp->dn_type; 618 dn->dn_nblkptr = dnp->dn_nblkptr; 619 dn->dn_checksum = dnp->dn_checksum; 620 dn->dn_compress = dnp->dn_compress; 621 dn->dn_bonustype = dnp->dn_bonustype; 622 dn->dn_bonuslen = dnp->dn_bonuslen; 623 dn->dn_num_slots = dnp->dn_extra_slots + 1; 624 dn->dn_maxblkid = dnp->dn_maxblkid; 625 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 626 dn->dn_id_flags = 0; 627 628 dn->dn_storage_type = DMU_OT_NONE; 629 630 dmu_zfetch_init(&dn->dn_zfetch, dn); 631 632 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 633 ASSERT(zrl_is_locked(&dnh->dnh_zrlock)); 634 ASSERT(!DN_SLOT_IS_PTR(dnh->dnh_dnode)); 635 636 mutex_enter(&os->os_lock); 637 638 /* 639 * Exclude special dnodes from os_dnodes so an empty os_dnodes 640 * signifies that the special dnodes have no references from 641 * their children (the entries in os_dnodes). This allows 642 * dnode_destroy() to easily determine if the last child has 643 * been removed and then complete eviction of the objset. 644 */ 645 if (!DMU_OBJECT_IS_SPECIAL(object)) 646 list_insert_head(&os->os_dnodes, dn); 647 membar_producer(); 648 649 /* 650 * Everything else must be valid before assigning dn_objset 651 * makes the dnode eligible for dnode_move(). 652 */ 653 dn->dn_objset = os; 654 655 dnh->dnh_dnode = dn; 656 mutex_exit(&os->os_lock); 657 658 arc_space_consume(sizeof (dnode_t), ARC_SPACE_DNODE); 659 660 return (dn); 661 } 662 663 /* 664 * Caller must be holding the dnode handle, which is released upon return. 665 */ 666 static void 667 dnode_destroy(dnode_t *dn) 668 { 669 objset_t *os = dn->dn_objset; 670 boolean_t complete_os_eviction = B_FALSE; 671 672 ASSERT0((dn->dn_id_flags & DN_ID_NEW_EXIST)); 673 674 mutex_enter(&os->os_lock); 675 POINTER_INVALIDATE(&dn->dn_objset); 676 if (!DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 677 list_remove(&os->os_dnodes, dn); 678 complete_os_eviction = 679 list_is_empty(&os->os_dnodes) && 680 list_link_active(&os->os_evicting_node); 681 } 682 mutex_exit(&os->os_lock); 683 684 /* the dnode can no longer move, so we can release the handle */ 685 if (!zrl_is_locked(&dn->dn_handle->dnh_zrlock)) 686 zrl_remove(&dn->dn_handle->dnh_zrlock); 687 688 dn->dn_allocated_txg = 0; 689 dn->dn_free_txg = 0; 690 dn->dn_assigned_txg = 0; 691 dn->dn_dirtycnt = 0; 692 693 if (dn->dn_bonus != NULL) { 694 mutex_enter(&dn->dn_bonus->db_mtx); 695 dbuf_destroy(dn->dn_bonus); 696 dn->dn_bonus = NULL; 697 } 698 dn->dn_zio = NULL; 699 700 dn->dn_have_spill = B_FALSE; 701 dn->dn_oldused = 0; 702 dn->dn_oldflags = 0; 703 dn->dn_olduid = 0; 704 dn->dn_oldgid = 0; 705 dn->dn_oldprojid = ZFS_DEFAULT_PROJID; 706 dn->dn_newuid = 0; 707 dn->dn_newgid = 0; 708 dn->dn_newprojid = ZFS_DEFAULT_PROJID; 709 dn->dn_id_flags = 0; 710 711 dn->dn_storage_type = DMU_OT_NONE; 712 713 dmu_zfetch_fini(&dn->dn_zfetch); 714 kmem_cache_free(dnode_cache, dn); 715 arc_space_return(sizeof (dnode_t), ARC_SPACE_DNODE); 716 717 if (complete_os_eviction) 718 dmu_objset_evict_done(os); 719 } 720 721 void 722 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 723 dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx) 724 { 725 int i; 726 727 ASSERT3U(dn_slots, >, 0); 728 ASSERT3U(dn_slots << DNODE_SHIFT, <=, 729 spa_maxdnodesize(dmu_objset_spa(dn->dn_objset))); 730 ASSERT3U(blocksize, <=, 731 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 732 if (blocksize == 0) 733 blocksize = 1 << zfs_default_bs; 734 else 735 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 736 737 if (ibs == 0) 738 ibs = zfs_default_ibs; 739 740 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 741 742 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d dn_slots=%d\n", 743 dn->dn_objset, (u_longlong_t)dn->dn_object, 744 (u_longlong_t)tx->tx_txg, blocksize, ibs, dn_slots); 745 DNODE_STAT_BUMP(dnode_allocate); 746 747 ASSERT(dn->dn_type == DMU_OT_NONE); 748 ASSERT0(memcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t))); 749 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 750 ASSERT(ot != DMU_OT_NONE); 751 ASSERT(DMU_OT_IS_VALID(ot)); 752 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 753 (bonustype == DMU_OT_SA && bonuslen == 0) || 754 (bonustype == DMU_OTN_UINT64_METADATA && bonuslen == 0) || 755 (bonustype != DMU_OT_NONE && bonuslen != 0)); 756 ASSERT(DMU_OT_IS_VALID(bonustype)); 757 ASSERT3U(bonuslen, <=, DN_SLOTS_TO_BONUSLEN(dn_slots)); 758 ASSERT(dn->dn_type == DMU_OT_NONE); 759 ASSERT0(dn->dn_maxblkid); 760 ASSERT0(dn->dn_allocated_txg); 761 ASSERT0(dn->dn_assigned_txg); 762 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 763 ASSERT3U(zfs_refcount_count(&dn->dn_holds), <=, 1); 764 ASSERT(avl_is_empty(&dn->dn_dbufs)); 765 766 for (i = 0; i < TXG_SIZE; i++) { 767 ASSERT0(dn->dn_next_nblkptr[i]); 768 ASSERT0(dn->dn_next_nlevels[i]); 769 ASSERT0(dn->dn_next_indblkshift[i]); 770 ASSERT0(dn->dn_next_bonuslen[i]); 771 ASSERT0(dn->dn_next_bonustype[i]); 772 ASSERT0(dn->dn_rm_spillblk[i]); 773 ASSERT0(dn->dn_next_blksz[i]); 774 ASSERT0(dn->dn_next_maxblkid[i]); 775 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i])); 776 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 777 ASSERT0P(dn->dn_free_ranges[i]); 778 } 779 780 dn->dn_type = ot; 781 dnode_setdblksz(dn, blocksize); 782 dn->dn_indblkshift = ibs; 783 dn->dn_nlevels = 1; 784 dn->dn_num_slots = dn_slots; 785 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 786 dn->dn_nblkptr = 1; 787 else { 788 dn->dn_nblkptr = MIN(DN_MAX_NBLKPTR, 789 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 790 SPA_BLKPTRSHIFT)); 791 } 792 793 dn->dn_bonustype = bonustype; 794 dn->dn_bonuslen = bonuslen; 795 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 796 dn->dn_compress = ZIO_COMPRESS_INHERIT; 797 798 dn->dn_free_txg = 0; 799 dn->dn_dirtycnt = 0; 800 801 dn->dn_allocated_txg = tx->tx_txg; 802 dn->dn_id_flags = 0; 803 804 dnode_setdirty(dn, tx); 805 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 806 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 807 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 808 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 809 } 810 811 void 812 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 813 dmu_object_type_t bonustype, int bonuslen, int dn_slots, 814 boolean_t keep_spill, dmu_tx_t *tx) 815 { 816 int nblkptr; 817 818 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 819 ASSERT3U(blocksize, <=, 820 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 821 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 822 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 823 ASSERT(tx->tx_txg != 0); 824 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 825 (bonustype != DMU_OT_NONE && bonuslen != 0) || 826 (bonustype == DMU_OT_SA && bonuslen == 0)); 827 ASSERT(DMU_OT_IS_VALID(bonustype)); 828 ASSERT3U(bonuslen, <=, 829 DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(dn->dn_objset)))); 830 ASSERT3U(bonuslen, <=, DN_BONUS_SIZE(dn_slots << DNODE_SHIFT)); 831 832 dnode_free_interior_slots(dn); 833 DNODE_STAT_BUMP(dnode_reallocate); 834 835 /* clean up any unreferenced dbufs */ 836 dnode_evict_dbufs(dn); 837 838 dn->dn_id_flags = 0; 839 840 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 841 dnode_setdirty(dn, tx); 842 if (dn->dn_datablksz != blocksize) { 843 /* change blocksize */ 844 ASSERT0(dn->dn_maxblkid); 845 ASSERT(BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 846 dnode_block_freed(dn, 0)); 847 848 dnode_setdblksz(dn, blocksize); 849 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = blocksize; 850 } 851 if (dn->dn_bonuslen != bonuslen) 852 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = bonuslen; 853 854 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 855 nblkptr = 1; 856 else 857 nblkptr = MIN(DN_MAX_NBLKPTR, 858 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 859 SPA_BLKPTRSHIFT)); 860 if (dn->dn_bonustype != bonustype) 861 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = bonustype; 862 if (dn->dn_nblkptr != nblkptr) 863 dn->dn_next_nblkptr[tx->tx_txg & TXG_MASK] = nblkptr; 864 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR && !keep_spill) { 865 dbuf_rm_spill(dn, tx); 866 dnode_rm_spill(dn, tx); 867 } 868 869 rw_exit(&dn->dn_struct_rwlock); 870 871 /* change type */ 872 dn->dn_type = ot; 873 874 /* change bonus size and type */ 875 mutex_enter(&dn->dn_mtx); 876 dn->dn_bonustype = bonustype; 877 dn->dn_bonuslen = bonuslen; 878 dn->dn_num_slots = dn_slots; 879 dn->dn_nblkptr = nblkptr; 880 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 881 dn->dn_compress = ZIO_COMPRESS_INHERIT; 882 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 883 884 /* fix up the bonus db_size */ 885 if (dn->dn_bonus) { 886 dn->dn_bonus->db.db_size = 887 DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) - 888 (dn->dn_nblkptr-1) * sizeof (blkptr_t); 889 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 890 } 891 892 dn->dn_allocated_txg = tx->tx_txg; 893 mutex_exit(&dn->dn_mtx); 894 } 895 896 #ifdef _KERNEL 897 static void 898 dnode_move_impl(dnode_t *odn, dnode_t *ndn) 899 { 900 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 901 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 902 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 903 904 /* Copy fields. */ 905 ndn->dn_objset = odn->dn_objset; 906 ndn->dn_object = odn->dn_object; 907 ndn->dn_dbuf = odn->dn_dbuf; 908 ndn->dn_handle = odn->dn_handle; 909 ndn->dn_phys = odn->dn_phys; 910 ndn->dn_type = odn->dn_type; 911 ndn->dn_bonuslen = odn->dn_bonuslen; 912 ndn->dn_bonustype = odn->dn_bonustype; 913 ndn->dn_nblkptr = odn->dn_nblkptr; 914 ndn->dn_checksum = odn->dn_checksum; 915 ndn->dn_compress = odn->dn_compress; 916 ndn->dn_nlevels = odn->dn_nlevels; 917 ndn->dn_indblkshift = odn->dn_indblkshift; 918 ndn->dn_datablkshift = odn->dn_datablkshift; 919 ndn->dn_datablkszsec = odn->dn_datablkszsec; 920 ndn->dn_datablksz = odn->dn_datablksz; 921 ndn->dn_maxblkid = odn->dn_maxblkid; 922 ndn->dn_num_slots = odn->dn_num_slots; 923 memcpy(ndn->dn_next_type, odn->dn_next_type, 924 sizeof (odn->dn_next_type)); 925 memcpy(ndn->dn_next_nblkptr, odn->dn_next_nblkptr, 926 sizeof (odn->dn_next_nblkptr)); 927 memcpy(ndn->dn_next_nlevels, odn->dn_next_nlevels, 928 sizeof (odn->dn_next_nlevels)); 929 memcpy(ndn->dn_next_indblkshift, odn->dn_next_indblkshift, 930 sizeof (odn->dn_next_indblkshift)); 931 memcpy(ndn->dn_next_bonustype, odn->dn_next_bonustype, 932 sizeof (odn->dn_next_bonustype)); 933 memcpy(ndn->dn_rm_spillblk, odn->dn_rm_spillblk, 934 sizeof (odn->dn_rm_spillblk)); 935 memcpy(ndn->dn_next_bonuslen, odn->dn_next_bonuslen, 936 sizeof (odn->dn_next_bonuslen)); 937 memcpy(ndn->dn_next_blksz, odn->dn_next_blksz, 938 sizeof (odn->dn_next_blksz)); 939 memcpy(ndn->dn_next_maxblkid, odn->dn_next_maxblkid, 940 sizeof (odn->dn_next_maxblkid)); 941 for (int i = 0; i < TXG_SIZE; i++) { 942 list_move_tail(&ndn->dn_dirty_records[i], 943 &odn->dn_dirty_records[i]); 944 } 945 memcpy(ndn->dn_free_ranges, odn->dn_free_ranges, 946 sizeof (odn->dn_free_ranges)); 947 ndn->dn_allocated_txg = odn->dn_allocated_txg; 948 ndn->dn_free_txg = odn->dn_free_txg; 949 ndn->dn_assigned_txg = odn->dn_assigned_txg; 950 ndn->dn_dirtycnt = odn->dn_dirtycnt; 951 ASSERT0(zfs_refcount_count(&odn->dn_tx_holds)); 952 zfs_refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 953 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 954 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 955 ndn->dn_dbufs_count = odn->dn_dbufs_count; 956 ndn->dn_bonus = odn->dn_bonus; 957 ndn->dn_have_spill = odn->dn_have_spill; 958 ndn->dn_zio = odn->dn_zio; 959 ndn->dn_oldused = odn->dn_oldused; 960 ndn->dn_oldflags = odn->dn_oldflags; 961 ndn->dn_olduid = odn->dn_olduid; 962 ndn->dn_oldgid = odn->dn_oldgid; 963 ndn->dn_oldprojid = odn->dn_oldprojid; 964 ndn->dn_newuid = odn->dn_newuid; 965 ndn->dn_newgid = odn->dn_newgid; 966 ndn->dn_newprojid = odn->dn_newprojid; 967 ndn->dn_id_flags = odn->dn_id_flags; 968 ndn->dn_storage_type = odn->dn_storage_type; 969 dmu_zfetch_init(&ndn->dn_zfetch, ndn); 970 971 /* 972 * Update back pointers. Updating the handle fixes the back pointer of 973 * every descendant dbuf as well as the bonus dbuf. 974 */ 975 ASSERT(ndn->dn_handle->dnh_dnode == odn); 976 ndn->dn_handle->dnh_dnode = ndn; 977 978 /* 979 * Invalidate the original dnode by clearing all of its back pointers. 980 */ 981 odn->dn_dbuf = NULL; 982 odn->dn_handle = NULL; 983 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 984 offsetof(dmu_buf_impl_t, db_link)); 985 odn->dn_dbufs_count = 0; 986 odn->dn_bonus = NULL; 987 dmu_zfetch_fini(&odn->dn_zfetch); 988 989 /* 990 * Set the low bit of the objset pointer to ensure that dnode_move() 991 * recognizes the dnode as invalid in any subsequent callback. 992 */ 993 POINTER_INVALIDATE(&odn->dn_objset); 994 995 /* 996 * Satisfy the destructor. 997 */ 998 for (int i = 0; i < TXG_SIZE; i++) { 999 list_create(&odn->dn_dirty_records[i], 1000 sizeof (dbuf_dirty_record_t), 1001 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 1002 odn->dn_free_ranges[i] = NULL; 1003 odn->dn_next_nlevels[i] = 0; 1004 odn->dn_next_indblkshift[i] = 0; 1005 odn->dn_next_bonustype[i] = 0; 1006 odn->dn_rm_spillblk[i] = 0; 1007 odn->dn_next_bonuslen[i] = 0; 1008 odn->dn_next_blksz[i] = 0; 1009 } 1010 odn->dn_allocated_txg = 0; 1011 odn->dn_free_txg = 0; 1012 odn->dn_assigned_txg = 0; 1013 odn->dn_dirtycnt = 0; 1014 odn->dn_have_spill = B_FALSE; 1015 odn->dn_zio = NULL; 1016 odn->dn_oldused = 0; 1017 odn->dn_oldflags = 0; 1018 odn->dn_olduid = 0; 1019 odn->dn_oldgid = 0; 1020 odn->dn_oldprojid = ZFS_DEFAULT_PROJID; 1021 odn->dn_newuid = 0; 1022 odn->dn_newgid = 0; 1023 odn->dn_newprojid = ZFS_DEFAULT_PROJID; 1024 odn->dn_id_flags = 0; 1025 odn->dn_storage_type = DMU_OT_NONE; 1026 1027 /* 1028 * Mark the dnode. 1029 */ 1030 ndn->dn_moved = 1; 1031 odn->dn_moved = (uint8_t)-1; 1032 } 1033 1034 static kmem_cbrc_t 1035 dnode_move(void *buf, void *newbuf, size_t size, void *arg) 1036 { 1037 dnode_t *odn = buf, *ndn = newbuf; 1038 objset_t *os; 1039 int64_t refcount; 1040 uint32_t dbufs; 1041 1042 #ifndef USE_DNODE_HANDLE 1043 /* 1044 * We can't move dnodes if dbufs reference them directly without 1045 * using handles and respecitve locking. Unless USE_DNODE_HANDLE 1046 * is defined the code below is only to make sure it still builds, 1047 * but it should never be used, since it is unsafe. 1048 */ 1049 #ifdef ZFS_DEBUG 1050 PANIC("dnode_move() called without USE_DNODE_HANDLE"); 1051 #endif 1052 return (KMEM_CBRC_NO); 1053 #endif 1054 1055 /* 1056 * The dnode is on the objset's list of known dnodes if the objset 1057 * pointer is valid. We set the low bit of the objset pointer when 1058 * freeing the dnode to invalidate it, and the memory patterns written 1059 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 1060 * A newly created dnode sets the objset pointer last of all to indicate 1061 * that the dnode is known and in a valid state to be moved by this 1062 * function. 1063 */ 1064 os = odn->dn_objset; 1065 if (!POINTER_IS_VALID(os)) { 1066 DNODE_STAT_BUMP(dnode_move_invalid); 1067 return (KMEM_CBRC_DONT_KNOW); 1068 } 1069 1070 /* 1071 * Ensure that the objset does not go away during the move. 1072 */ 1073 rw_enter(&os_lock, RW_WRITER); 1074 if (os != odn->dn_objset) { 1075 rw_exit(&os_lock); 1076 DNODE_STAT_BUMP(dnode_move_recheck1); 1077 return (KMEM_CBRC_DONT_KNOW); 1078 } 1079 1080 /* 1081 * If the dnode is still valid, then so is the objset. We know that no 1082 * valid objset can be freed while we hold os_lock, so we can safely 1083 * ensure that the objset remains in use. 1084 */ 1085 mutex_enter(&os->os_lock); 1086 1087 /* 1088 * Recheck the objset pointer in case the dnode was removed just before 1089 * acquiring the lock. 1090 */ 1091 if (os != odn->dn_objset) { 1092 mutex_exit(&os->os_lock); 1093 rw_exit(&os_lock); 1094 DNODE_STAT_BUMP(dnode_move_recheck2); 1095 return (KMEM_CBRC_DONT_KNOW); 1096 } 1097 1098 /* 1099 * At this point we know that as long as we hold os->os_lock, the dnode 1100 * cannot be freed and fields within the dnode can be safely accessed. 1101 * The objset listing this dnode cannot go away as long as this dnode is 1102 * on its list. 1103 */ 1104 rw_exit(&os_lock); 1105 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 1106 mutex_exit(&os->os_lock); 1107 DNODE_STAT_BUMP(dnode_move_special); 1108 return (KMEM_CBRC_NO); 1109 } 1110 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 1111 1112 /* 1113 * Lock the dnode handle to prevent the dnode from obtaining any new 1114 * holds. This also prevents the descendant dbufs and the bonus dbuf 1115 * from accessing the dnode, so that we can discount their holds. The 1116 * handle is safe to access because we know that while the dnode cannot 1117 * go away, neither can its handle. Once we hold dnh_zrlock, we can 1118 * safely move any dnode referenced only by dbufs. 1119 */ 1120 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 1121 mutex_exit(&os->os_lock); 1122 DNODE_STAT_BUMP(dnode_move_handle); 1123 return (KMEM_CBRC_LATER); 1124 } 1125 1126 /* 1127 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 1128 * We need to guarantee that there is a hold for every dbuf in order to 1129 * determine whether the dnode is actively referenced. Falsely matching 1130 * a dbuf to an active hold would lead to an unsafe move. It's possible 1131 * that a thread already having an active dnode hold is about to add a 1132 * dbuf, and we can't compare hold and dbuf counts while the add is in 1133 * progress. 1134 */ 1135 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 1136 zrl_exit(&odn->dn_handle->dnh_zrlock); 1137 mutex_exit(&os->os_lock); 1138 DNODE_STAT_BUMP(dnode_move_rwlock); 1139 return (KMEM_CBRC_LATER); 1140 } 1141 1142 /* 1143 * A dbuf may be removed (evicted) without an active dnode hold. In that 1144 * case, the dbuf count is decremented under the handle lock before the 1145 * dbuf's hold is released. This order ensures that if we count the hold 1146 * after the dbuf is removed but before its hold is released, we will 1147 * treat the unmatched hold as active and exit safely. If we count the 1148 * hold before the dbuf is removed, the hold is discounted, and the 1149 * removal is blocked until the move completes. 1150 */ 1151 refcount = zfs_refcount_count(&odn->dn_holds); 1152 ASSERT(refcount >= 0); 1153 dbufs = DN_DBUFS_COUNT(odn); 1154 1155 /* We can't have more dbufs than dnode holds. */ 1156 ASSERT3U(dbufs, <=, refcount); 1157 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 1158 uint32_t, dbufs); 1159 1160 if (refcount > dbufs) { 1161 rw_exit(&odn->dn_struct_rwlock); 1162 zrl_exit(&odn->dn_handle->dnh_zrlock); 1163 mutex_exit(&os->os_lock); 1164 DNODE_STAT_BUMP(dnode_move_active); 1165 return (KMEM_CBRC_LATER); 1166 } 1167 1168 rw_exit(&odn->dn_struct_rwlock); 1169 1170 /* 1171 * At this point we know that anyone with a hold on the dnode is not 1172 * actively referencing it. The dnode is known and in a valid state to 1173 * move. We're holding the locks needed to execute the critical section. 1174 */ 1175 dnode_move_impl(odn, ndn); 1176 1177 list_link_replace(&odn->dn_link, &ndn->dn_link); 1178 /* If the dnode was safe to move, the refcount cannot have changed. */ 1179 ASSERT(refcount == zfs_refcount_count(&ndn->dn_holds)); 1180 ASSERT(dbufs == DN_DBUFS_COUNT(ndn)); 1181 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 1182 mutex_exit(&os->os_lock); 1183 1184 return (KMEM_CBRC_YES); 1185 } 1186 #endif /* _KERNEL */ 1187 1188 static void 1189 dnode_slots_hold(dnode_children_t *children, int idx, int slots) 1190 { 1191 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1192 1193 for (int i = idx; i < idx + slots; i++) { 1194 dnode_handle_t *dnh = &children->dnc_children[i]; 1195 zrl_add(&dnh->dnh_zrlock); 1196 } 1197 } 1198 1199 static void 1200 dnode_slots_rele(dnode_children_t *children, int idx, int slots) 1201 { 1202 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1203 1204 for (int i = idx; i < idx + slots; i++) { 1205 dnode_handle_t *dnh = &children->dnc_children[i]; 1206 1207 if (zrl_is_locked(&dnh->dnh_zrlock)) 1208 zrl_exit(&dnh->dnh_zrlock); 1209 else 1210 zrl_remove(&dnh->dnh_zrlock); 1211 } 1212 } 1213 1214 static int 1215 dnode_slots_tryenter(dnode_children_t *children, int idx, int slots) 1216 { 1217 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1218 1219 for (int i = idx; i < idx + slots; i++) { 1220 dnode_handle_t *dnh = &children->dnc_children[i]; 1221 1222 if (!zrl_tryenter(&dnh->dnh_zrlock)) { 1223 for (int j = idx; j < i; j++) { 1224 dnh = &children->dnc_children[j]; 1225 zrl_exit(&dnh->dnh_zrlock); 1226 } 1227 1228 return (0); 1229 } 1230 } 1231 1232 return (1); 1233 } 1234 1235 static void 1236 dnode_set_slots(dnode_children_t *children, int idx, int slots, void *ptr) 1237 { 1238 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1239 1240 for (int i = idx; i < idx + slots; i++) { 1241 dnode_handle_t *dnh = &children->dnc_children[i]; 1242 dnh->dnh_dnode = ptr; 1243 } 1244 } 1245 1246 static boolean_t 1247 dnode_check_slots_free(dnode_children_t *children, int idx, int slots) 1248 { 1249 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1250 1251 /* 1252 * If all dnode slots are either already free or 1253 * evictable return B_TRUE. 1254 */ 1255 for (int i = idx; i < idx + slots; i++) { 1256 dnode_handle_t *dnh = &children->dnc_children[i]; 1257 dnode_t *dn = dnh->dnh_dnode; 1258 1259 if (dn == DN_SLOT_FREE) { 1260 continue; 1261 } else if (DN_SLOT_IS_PTR(dn)) { 1262 mutex_enter(&dn->dn_mtx); 1263 boolean_t can_free = (dn->dn_type == DMU_OT_NONE && 1264 dn->dn_dirtycnt == 0 && 1265 zfs_refcount_is_zero(&dn->dn_holds)); 1266 mutex_exit(&dn->dn_mtx); 1267 1268 if (!can_free) 1269 return (B_FALSE); 1270 else 1271 continue; 1272 } else { 1273 return (B_FALSE); 1274 } 1275 } 1276 1277 return (B_TRUE); 1278 } 1279 1280 static uint_t 1281 dnode_reclaim_slots(dnode_children_t *children, int idx, int slots) 1282 { 1283 uint_t reclaimed = 0; 1284 1285 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1286 1287 for (int i = idx; i < idx + slots; i++) { 1288 dnode_handle_t *dnh = &children->dnc_children[i]; 1289 1290 ASSERT(zrl_is_locked(&dnh->dnh_zrlock)); 1291 1292 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1293 ASSERT3S(dnh->dnh_dnode->dn_type, ==, DMU_OT_NONE); 1294 dnode_destroy(dnh->dnh_dnode); 1295 dnh->dnh_dnode = DN_SLOT_FREE; 1296 reclaimed++; 1297 } 1298 } 1299 1300 return (reclaimed); 1301 } 1302 1303 void 1304 dnode_free_interior_slots(dnode_t *dn) 1305 { 1306 dnode_children_t *children = dmu_buf_get_user(&dn->dn_dbuf->db); 1307 int epb = dn->dn_dbuf->db.db_size >> DNODE_SHIFT; 1308 int idx = (dn->dn_object & (epb - 1)) + 1; 1309 int slots = dn->dn_num_slots - 1; 1310 1311 if (slots == 0) 1312 return; 1313 1314 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1315 1316 while (!dnode_slots_tryenter(children, idx, slots)) { 1317 DNODE_STAT_BUMP(dnode_free_interior_lock_retry); 1318 kpreempt(KPREEMPT_SYNC); 1319 } 1320 1321 dnode_set_slots(children, idx, slots, DN_SLOT_FREE); 1322 dnode_slots_rele(children, idx, slots); 1323 } 1324 1325 void 1326 dnode_special_close(dnode_handle_t *dnh) 1327 { 1328 dnode_t *dn = dnh->dnh_dnode; 1329 1330 /* 1331 * Ensure dnode_rele_and_unlock() has released dn_mtx, after final 1332 * zfs_refcount_remove() 1333 */ 1334 mutex_enter(&dn->dn_mtx); 1335 if (zfs_refcount_count(&dn->dn_holds) > 0) 1336 cv_wait(&dn->dn_nodnholds, &dn->dn_mtx); 1337 mutex_exit(&dn->dn_mtx); 1338 ASSERT3U(zfs_refcount_count(&dn->dn_holds), ==, 0); 1339 1340 ASSERT(dn->dn_dbuf == NULL || 1341 dmu_buf_get_user(&dn->dn_dbuf->db) == NULL); 1342 zrl_add(&dnh->dnh_zrlock); 1343 dnode_destroy(dn); /* implicit zrl_remove() */ 1344 zrl_destroy(&dnh->dnh_zrlock); 1345 dnh->dnh_dnode = NULL; 1346 } 1347 1348 void 1349 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 1350 dnode_handle_t *dnh) 1351 { 1352 dnode_t *dn; 1353 1354 zrl_init(&dnh->dnh_zrlock); 1355 VERIFY3U(1, ==, zrl_tryenter(&dnh->dnh_zrlock)); 1356 1357 dn = dnode_create(os, dnp, NULL, object, dnh); 1358 DNODE_VERIFY(dn); 1359 1360 zrl_exit(&dnh->dnh_zrlock); 1361 } 1362 1363 static void 1364 dnode_buf_evict_async(void *dbu) 1365 { 1366 dnode_children_t *dnc = dbu; 1367 1368 DNODE_STAT_BUMP(dnode_buf_evict); 1369 1370 for (int i = 0; i < dnc->dnc_count; i++) { 1371 dnode_handle_t *dnh = &dnc->dnc_children[i]; 1372 dnode_t *dn; 1373 1374 /* 1375 * The dnode handle lock guards against the dnode moving to 1376 * another valid address, so there is no need here to guard 1377 * against changes to or from NULL. 1378 */ 1379 if (!DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1380 zrl_destroy(&dnh->dnh_zrlock); 1381 dnh->dnh_dnode = DN_SLOT_UNINIT; 1382 continue; 1383 } 1384 1385 zrl_add(&dnh->dnh_zrlock); 1386 dn = dnh->dnh_dnode; 1387 /* 1388 * If there are holds on this dnode, then there should 1389 * be holds on the dnode's containing dbuf as well; thus 1390 * it wouldn't be eligible for eviction and this function 1391 * would not have been called. 1392 */ 1393 ASSERT(zfs_refcount_is_zero(&dn->dn_holds)); 1394 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 1395 1396 dnode_destroy(dn); /* implicit zrl_remove() for first slot */ 1397 zrl_destroy(&dnh->dnh_zrlock); 1398 dnh->dnh_dnode = DN_SLOT_UNINIT; 1399 } 1400 kmem_free(dnc, sizeof (dnode_children_t) + 1401 dnc->dnc_count * sizeof (dnode_handle_t)); 1402 } 1403 1404 /* 1405 * When the DNODE_MUST_BE_FREE flag is set, the "slots" parameter is used 1406 * to ensure the hole at the specified object offset is large enough to 1407 * hold the dnode being created. The slots parameter is also used to ensure 1408 * a dnode does not span multiple dnode blocks. In both of these cases, if 1409 * a failure occurs, ENOSPC is returned. Keep in mind, these failure cases 1410 * are only possible when using DNODE_MUST_BE_FREE. 1411 * 1412 * If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0. 1413 * dnode_hold_impl() will check if the requested dnode is already consumed 1414 * as an extra dnode slot by an large dnode, in which case it returns 1415 * ENOENT. 1416 * 1417 * If the DNODE_DRY_RUN flag is set, we don't actually hold the dnode, just 1418 * return whether the hold would succeed or not. tag and dnp should set to 1419 * NULL in this case. 1420 * 1421 * errors: 1422 * EINVAL - Invalid object number or flags. 1423 * ENOSPC - Hole too small to fulfill "slots" request (DNODE_MUST_BE_FREE) 1424 * EEXIST - Refers to an allocated dnode (DNODE_MUST_BE_FREE) 1425 * - Refers to a freeing dnode (DNODE_MUST_BE_FREE) 1426 * - Refers to an interior dnode slot (DNODE_MUST_BE_ALLOCATED) 1427 * ENOENT - The requested dnode is not allocated (DNODE_MUST_BE_ALLOCATED) 1428 * - The requested dnode is being freed (DNODE_MUST_BE_ALLOCATED) 1429 * EIO - I/O error when reading the meta dnode dbuf. 1430 * 1431 * succeeds even for free dnodes. 1432 */ 1433 int 1434 dnode_hold_impl(objset_t *os, uint64_t object, int flag, int slots, 1435 const void *tag, dnode_t **dnp) 1436 { 1437 int epb, idx, err; 1438 int drop_struct_lock = FALSE; 1439 int type; 1440 uint64_t blk; 1441 dnode_t *mdn, *dn; 1442 dmu_buf_impl_t *db; 1443 dnode_children_t *dnc; 1444 dnode_phys_t *dn_block; 1445 dnode_handle_t *dnh; 1446 1447 ASSERT(!(flag & DNODE_MUST_BE_ALLOCATED) || (slots == 0)); 1448 ASSERT(!(flag & DNODE_MUST_BE_FREE) || (slots > 0)); 1449 IMPLY(flag & DNODE_DRY_RUN, (tag == NULL) && (dnp == NULL)); 1450 1451 /* 1452 * If you are holding the spa config lock as writer, you shouldn't 1453 * be asking the DMU to do *anything* unless it's the root pool 1454 * which may require us to read from the root filesystem while 1455 * holding some (not all) of the locks as writer. 1456 */ 1457 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1458 (spa_is_root(os->os_spa) && 1459 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1460 1461 ASSERT((flag & DNODE_MUST_BE_ALLOCATED) || (flag & DNODE_MUST_BE_FREE)); 1462 1463 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT || 1464 object == DMU_PROJECTUSED_OBJECT) { 1465 if (object == DMU_USERUSED_OBJECT) 1466 dn = DMU_USERUSED_DNODE(os); 1467 else if (object == DMU_GROUPUSED_OBJECT) 1468 dn = DMU_GROUPUSED_DNODE(os); 1469 else 1470 dn = DMU_PROJECTUSED_DNODE(os); 1471 if (dn == NULL) 1472 return (SET_ERROR(ENOENT)); 1473 type = dn->dn_type; 1474 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1475 return (SET_ERROR(ENOENT)); 1476 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1477 return (SET_ERROR(EEXIST)); 1478 DNODE_VERIFY(dn); 1479 /* Don't actually hold if dry run, just return 0 */ 1480 if (!(flag & DNODE_DRY_RUN)) { 1481 (void) zfs_refcount_add(&dn->dn_holds, tag); 1482 *dnp = dn; 1483 } 1484 return (0); 1485 } 1486 1487 if (object == 0 || object >= DN_MAX_OBJECT) 1488 return (SET_ERROR(EINVAL)); 1489 1490 mdn = DMU_META_DNODE(os); 1491 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1492 1493 DNODE_VERIFY(mdn); 1494 1495 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1496 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1497 drop_struct_lock = TRUE; 1498 } 1499 1500 blk = dbuf_whichblock(mdn, 0, object * sizeof (dnode_phys_t)); 1501 db = dbuf_hold(mdn, blk, FTAG); 1502 if (drop_struct_lock) 1503 rw_exit(&mdn->dn_struct_rwlock); 1504 if (db == NULL) { 1505 DNODE_STAT_BUMP(dnode_hold_dbuf_hold); 1506 return (SET_ERROR(EIO)); 1507 } 1508 1509 /* 1510 * We do not need to decrypt to read the dnode so it doesn't matter 1511 * if we get the encrypted or decrypted version. 1512 */ 1513 err = dbuf_read(db, NULL, DB_RF_CANFAIL | 1514 DMU_READ_NO_PREFETCH | DMU_READ_NO_DECRYPT); 1515 if (err) { 1516 DNODE_STAT_BUMP(dnode_hold_dbuf_read); 1517 dbuf_rele(db, FTAG); 1518 return (err); 1519 } 1520 1521 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1522 epb = db->db.db_size >> DNODE_SHIFT; 1523 1524 idx = object & (epb - 1); 1525 dn_block = (dnode_phys_t *)db->db.db_data; 1526 1527 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1528 dnc = dmu_buf_get_user(&db->db); 1529 dnh = NULL; 1530 if (dnc == NULL) { 1531 dnode_children_t *winner; 1532 int skip = 0; 1533 1534 dnc = kmem_zalloc(sizeof (dnode_children_t) + 1535 epb * sizeof (dnode_handle_t), KM_SLEEP); 1536 dnc->dnc_count = epb; 1537 dnh = &dnc->dnc_children[0]; 1538 1539 /* Initialize dnode slot status from dnode_phys_t */ 1540 for (int i = 0; i < epb; i++) { 1541 zrl_init(&dnh[i].dnh_zrlock); 1542 1543 if (skip) { 1544 skip--; 1545 continue; 1546 } 1547 1548 if (dn_block[i].dn_type != DMU_OT_NONE) { 1549 int interior = dn_block[i].dn_extra_slots; 1550 1551 dnode_set_slots(dnc, i, 1, DN_SLOT_ALLOCATED); 1552 dnode_set_slots(dnc, i + 1, interior, 1553 DN_SLOT_INTERIOR); 1554 skip = interior; 1555 } else { 1556 dnh[i].dnh_dnode = DN_SLOT_FREE; 1557 skip = 0; 1558 } 1559 } 1560 1561 dmu_buf_init_user(&dnc->dnc_dbu, NULL, 1562 dnode_buf_evict_async, NULL); 1563 winner = dmu_buf_set_user(&db->db, &dnc->dnc_dbu); 1564 if (winner != NULL) { 1565 1566 for (int i = 0; i < epb; i++) 1567 zrl_destroy(&dnh[i].dnh_zrlock); 1568 1569 kmem_free(dnc, sizeof (dnode_children_t) + 1570 epb * sizeof (dnode_handle_t)); 1571 dnc = winner; 1572 } 1573 } 1574 1575 ASSERT(dnc->dnc_count == epb); 1576 1577 if (flag & DNODE_MUST_BE_ALLOCATED) { 1578 slots = 1; 1579 1580 dnode_slots_hold(dnc, idx, slots); 1581 dnh = &dnc->dnc_children[idx]; 1582 1583 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1584 dn = dnh->dnh_dnode; 1585 } else if (dnh->dnh_dnode == DN_SLOT_INTERIOR) { 1586 DNODE_STAT_BUMP(dnode_hold_alloc_interior); 1587 dnode_slots_rele(dnc, idx, slots); 1588 dbuf_rele(db, FTAG); 1589 return (SET_ERROR(EEXIST)); 1590 } else if (dnh->dnh_dnode != DN_SLOT_ALLOCATED) { 1591 DNODE_STAT_BUMP(dnode_hold_alloc_misses); 1592 dnode_slots_rele(dnc, idx, slots); 1593 dbuf_rele(db, FTAG); 1594 return (SET_ERROR(ENOENT)); 1595 } else { 1596 dnode_slots_rele(dnc, idx, slots); 1597 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1598 DNODE_STAT_BUMP(dnode_hold_alloc_lock_retry); 1599 kpreempt(KPREEMPT_SYNC); 1600 } 1601 1602 /* 1603 * Someone else won the race and called dnode_create() 1604 * after we checked DN_SLOT_IS_PTR() above but before 1605 * we acquired the lock. 1606 */ 1607 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1608 DNODE_STAT_BUMP(dnode_hold_alloc_lock_misses); 1609 dn = dnh->dnh_dnode; 1610 } else { 1611 dn = dnode_create(os, dn_block + idx, db, 1612 object, dnh); 1613 dmu_buf_add_user_size(&db->db, 1614 sizeof (dnode_t)); 1615 } 1616 } 1617 1618 mutex_enter(&dn->dn_mtx); 1619 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg != 0) { 1620 DNODE_STAT_BUMP(dnode_hold_alloc_type_none); 1621 mutex_exit(&dn->dn_mtx); 1622 dnode_slots_rele(dnc, idx, slots); 1623 dbuf_rele(db, FTAG); 1624 return (SET_ERROR(ENOENT)); 1625 } 1626 1627 /* Don't actually hold if dry run, just return 0 */ 1628 if (flag & DNODE_DRY_RUN) { 1629 mutex_exit(&dn->dn_mtx); 1630 dnode_slots_rele(dnc, idx, slots); 1631 dbuf_rele(db, FTAG); 1632 return (0); 1633 } 1634 1635 DNODE_STAT_BUMP(dnode_hold_alloc_hits); 1636 } else if (flag & DNODE_MUST_BE_FREE) { 1637 1638 if (idx + slots - 1 >= DNODES_PER_BLOCK) { 1639 DNODE_STAT_BUMP(dnode_hold_free_overflow); 1640 dbuf_rele(db, FTAG); 1641 return (SET_ERROR(ENOSPC)); 1642 } 1643 1644 dnode_slots_hold(dnc, idx, slots); 1645 1646 if (!dnode_check_slots_free(dnc, idx, slots)) { 1647 DNODE_STAT_BUMP(dnode_hold_free_misses); 1648 dnode_slots_rele(dnc, idx, slots); 1649 dbuf_rele(db, FTAG); 1650 return (SET_ERROR(ENOSPC)); 1651 } 1652 1653 dnode_slots_rele(dnc, idx, slots); 1654 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1655 DNODE_STAT_BUMP(dnode_hold_free_lock_retry); 1656 kpreempt(KPREEMPT_SYNC); 1657 } 1658 1659 if (!dnode_check_slots_free(dnc, idx, slots)) { 1660 DNODE_STAT_BUMP(dnode_hold_free_lock_misses); 1661 dnode_slots_rele(dnc, idx, slots); 1662 dbuf_rele(db, FTAG); 1663 return (SET_ERROR(ENOSPC)); 1664 } 1665 1666 /* 1667 * Allocated but otherwise free dnodes which would 1668 * be in the interior of a multi-slot dnodes need 1669 * to be freed. Single slot dnodes can be safely 1670 * re-purposed as a performance optimization. 1671 */ 1672 if (slots > 1) { 1673 uint_t reclaimed = 1674 dnode_reclaim_slots(dnc, idx + 1, slots - 1); 1675 if (reclaimed > 0) 1676 dmu_buf_sub_user_size(&db->db, 1677 reclaimed * sizeof (dnode_t)); 1678 } 1679 1680 dnh = &dnc->dnc_children[idx]; 1681 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1682 dn = dnh->dnh_dnode; 1683 } else { 1684 dn = dnode_create(os, dn_block + idx, db, 1685 object, dnh); 1686 dmu_buf_add_user_size(&db->db, sizeof (dnode_t)); 1687 } 1688 1689 mutex_enter(&dn->dn_mtx); 1690 if (!zfs_refcount_is_zero(&dn->dn_holds) || dn->dn_free_txg) { 1691 DNODE_STAT_BUMP(dnode_hold_free_refcount); 1692 mutex_exit(&dn->dn_mtx); 1693 dnode_slots_rele(dnc, idx, slots); 1694 dbuf_rele(db, FTAG); 1695 return (SET_ERROR(EEXIST)); 1696 } 1697 1698 /* Don't actually hold if dry run, just return 0 */ 1699 if (flag & DNODE_DRY_RUN) { 1700 mutex_exit(&dn->dn_mtx); 1701 dnode_slots_rele(dnc, idx, slots); 1702 dbuf_rele(db, FTAG); 1703 return (0); 1704 } 1705 1706 dnode_set_slots(dnc, idx + 1, slots - 1, DN_SLOT_INTERIOR); 1707 DNODE_STAT_BUMP(dnode_hold_free_hits); 1708 } else { 1709 dbuf_rele(db, FTAG); 1710 return (SET_ERROR(EINVAL)); 1711 } 1712 1713 ASSERT0(dn->dn_free_txg); 1714 1715 if (zfs_refcount_add(&dn->dn_holds, tag) == 1) 1716 dbuf_add_ref(db, dnh); 1717 1718 mutex_exit(&dn->dn_mtx); 1719 1720 /* Now we can rely on the hold to prevent the dnode from moving. */ 1721 dnode_slots_rele(dnc, idx, slots); 1722 1723 DNODE_VERIFY(dn); 1724 ASSERT3P(dnp, !=, NULL); 1725 ASSERT3P(dn->dn_dbuf, ==, db); 1726 ASSERT3U(dn->dn_object, ==, object); 1727 dbuf_rele(db, FTAG); 1728 1729 *dnp = dn; 1730 return (0); 1731 } 1732 1733 /* 1734 * Return held dnode if the object is allocated, NULL if not. 1735 */ 1736 int 1737 dnode_hold(objset_t *os, uint64_t object, const void *tag, dnode_t **dnp) 1738 { 1739 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 0, tag, 1740 dnp)); 1741 } 1742 1743 /* 1744 * Can only add a reference if there is already at least one 1745 * reference on the dnode. Returns FALSE if unable to add a 1746 * new reference. 1747 */ 1748 static boolean_t 1749 dnode_add_ref_locked(dnode_t *dn, const void *tag) 1750 { 1751 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 1752 if (zfs_refcount_is_zero(&dn->dn_holds)) 1753 return (FALSE); 1754 VERIFY(1 < zfs_refcount_add(&dn->dn_holds, tag)); 1755 return (TRUE); 1756 } 1757 1758 boolean_t 1759 dnode_add_ref(dnode_t *dn, const void *tag) 1760 { 1761 mutex_enter(&dn->dn_mtx); 1762 boolean_t r = dnode_add_ref_locked(dn, tag); 1763 mutex_exit(&dn->dn_mtx); 1764 return (r); 1765 } 1766 1767 void 1768 dnode_rele(dnode_t *dn, const void *tag) 1769 { 1770 mutex_enter(&dn->dn_mtx); 1771 dnode_rele_and_unlock(dn, tag, B_FALSE); 1772 } 1773 1774 void 1775 dnode_rele_and_unlock(dnode_t *dn, const void *tag, boolean_t evicting) 1776 { 1777 uint64_t refs; 1778 /* Get while the hold prevents the dnode from moving. */ 1779 dmu_buf_impl_t *db = dn->dn_dbuf; 1780 dnode_handle_t *dnh = dn->dn_handle; 1781 1782 refs = zfs_refcount_remove(&dn->dn_holds, tag); 1783 if (refs == 0) 1784 cv_broadcast(&dn->dn_nodnholds); 1785 mutex_exit(&dn->dn_mtx); 1786 /* dnode could get destroyed at this point, so don't use it anymore */ 1787 1788 /* 1789 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1790 * indirectly by dbuf_rele() while relying on the dnode handle to 1791 * prevent the dnode from moving, since releasing the last hold could 1792 * result in the dnode's parent dbuf evicting its dnode handles. For 1793 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1794 * other direct or indirect hold on the dnode must first drop the dnode 1795 * handle. 1796 */ 1797 #ifdef ZFS_DEBUG 1798 ASSERT(refs > 0 || zrl_owner(&dnh->dnh_zrlock) != curthread); 1799 #endif 1800 1801 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1802 if (refs == 0 && db != NULL) { 1803 /* 1804 * Another thread could add a hold to the dnode handle in 1805 * dnode_hold_impl() while holding the parent dbuf. Since the 1806 * hold on the parent dbuf prevents the handle from being 1807 * destroyed, the hold on the handle is OK. We can't yet assert 1808 * that the handle has zero references, but that will be 1809 * asserted anyway when the handle gets destroyed. 1810 */ 1811 mutex_enter(&db->db_mtx); 1812 dbuf_rele_and_unlock(db, dnh, evicting); 1813 } 1814 } 1815 1816 /* 1817 * Test whether we can create a dnode at the specified location. 1818 */ 1819 int 1820 dnode_try_claim(objset_t *os, uint64_t object, int slots) 1821 { 1822 return (dnode_hold_impl(os, object, DNODE_MUST_BE_FREE | DNODE_DRY_RUN, 1823 slots, NULL, NULL)); 1824 } 1825 1826 /* 1827 * Test if the dnode is dirty, or carrying uncommitted records. 1828 * 1829 * dn_dirtycnt is the number of txgs this dnode is dirty on. It's incremented 1830 * in dnode_setdirty() the first time the dnode is dirtied on a txg, and 1831 * decremented in either dnode_rele_task() or userquota_updates_task() when the 1832 * txg is synced out. 1833 */ 1834 boolean_t 1835 dnode_is_dirty(dnode_t *dn) 1836 { 1837 mutex_enter(&dn->dn_mtx); 1838 boolean_t dirty = (dn->dn_dirtycnt != 0); 1839 mutex_exit(&dn->dn_mtx); 1840 return (dirty); 1841 } 1842 1843 void 1844 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1845 { 1846 objset_t *os = dn->dn_objset; 1847 uint64_t txg = tx->tx_txg; 1848 1849 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1850 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1851 return; 1852 } 1853 1854 DNODE_VERIFY(dn); 1855 1856 #ifdef ZFS_DEBUG 1857 mutex_enter(&dn->dn_mtx); 1858 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1859 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1860 mutex_exit(&dn->dn_mtx); 1861 #endif 1862 1863 /* 1864 * Determine old uid/gid when necessary 1865 */ 1866 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1867 1868 multilist_t *dirtylist = &os->os_dirty_dnodes[txg & TXG_MASK]; 1869 multilist_sublist_t *mls = multilist_sublist_lock_obj(dirtylist, dn); 1870 1871 /* 1872 * If we are already marked dirty, we're done. 1873 */ 1874 if (multilist_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1875 multilist_sublist_unlock(mls); 1876 return; 1877 } 1878 1879 ASSERT(!zfs_refcount_is_zero(&dn->dn_holds) || 1880 !avl_is_empty(&dn->dn_dbufs)); 1881 ASSERT(dn->dn_datablksz != 0); 1882 ASSERT0(dn->dn_next_bonuslen[txg & TXG_MASK]); 1883 ASSERT0(dn->dn_next_blksz[txg & TXG_MASK]); 1884 ASSERT0(dn->dn_next_bonustype[txg & TXG_MASK]); 1885 1886 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1887 (u_longlong_t)dn->dn_object, (u_longlong_t)txg); 1888 1889 multilist_sublist_insert_head(mls, dn); 1890 1891 multilist_sublist_unlock(mls); 1892 1893 /* 1894 * The dnode maintains a hold on its containing dbuf as 1895 * long as there are holds on it. Each instantiated child 1896 * dbuf maintains a hold on the dnode. When the last child 1897 * drops its hold, the dnode will drop its hold on the 1898 * containing dbuf. We add a "dirty hold" here so that the 1899 * dnode will hang around after we finish processing its 1900 * children. 1901 */ 1902 mutex_enter(&dn->dn_mtx); 1903 VERIFY(dnode_add_ref_locked(dn, (void *)(uintptr_t)tx->tx_txg)); 1904 dn->dn_dirtycnt++; 1905 ASSERT3U(dn->dn_dirtycnt, <=, 3); 1906 mutex_exit(&dn->dn_mtx); 1907 1908 (void) dbuf_dirty(dn->dn_dbuf, tx); 1909 1910 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1911 } 1912 1913 void 1914 dnode_free(dnode_t *dn, dmu_tx_t *tx) 1915 { 1916 mutex_enter(&dn->dn_mtx); 1917 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1918 mutex_exit(&dn->dn_mtx); 1919 return; 1920 } 1921 dn->dn_free_txg = tx->tx_txg; 1922 mutex_exit(&dn->dn_mtx); 1923 1924 dnode_setdirty(dn, tx); 1925 } 1926 1927 /* 1928 * Try to change the block size for the indicated dnode. This can only 1929 * succeed if there are no blocks allocated or dirty beyond first block 1930 */ 1931 int 1932 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1933 { 1934 dmu_buf_impl_t *db; 1935 int err; 1936 1937 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 1938 if (size == 0) 1939 size = SPA_MINBLOCKSIZE; 1940 else 1941 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1942 1943 if (ibs == dn->dn_indblkshift) 1944 ibs = 0; 1945 1946 if (size == dn->dn_datablksz && ibs == 0) 1947 return (0); 1948 1949 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1950 1951 /* Check for any allocated blocks beyond the first */ 1952 if (dn->dn_maxblkid != 0) 1953 goto fail; 1954 1955 mutex_enter(&dn->dn_dbufs_mtx); 1956 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1957 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1958 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1959 db->db_blkid != DMU_SPILL_BLKID) { 1960 mutex_exit(&dn->dn_dbufs_mtx); 1961 goto fail; 1962 } 1963 } 1964 mutex_exit(&dn->dn_dbufs_mtx); 1965 1966 if (ibs && dn->dn_nlevels != 1) 1967 goto fail; 1968 1969 dnode_setdirty(dn, tx); 1970 if (size != dn->dn_datablksz) { 1971 /* resize the old block */ 1972 err = dbuf_hold_impl(dn, 0, 0, TRUE, FALSE, FTAG, &db); 1973 if (err == 0) { 1974 dbuf_new_size(db, size, tx); 1975 } else if (err != ENOENT) { 1976 goto fail; 1977 } 1978 1979 dnode_setdblksz(dn, size); 1980 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = size; 1981 if (db) 1982 dbuf_rele(db, FTAG); 1983 } 1984 if (ibs) { 1985 dn->dn_indblkshift = ibs; 1986 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 1987 } 1988 1989 rw_exit(&dn->dn_struct_rwlock); 1990 return (0); 1991 1992 fail: 1993 rw_exit(&dn->dn_struct_rwlock); 1994 return (SET_ERROR(ENOTSUP)); 1995 } 1996 1997 static void 1998 dnode_set_nlevels_impl(dnode_t *dn, int new_nlevels, dmu_tx_t *tx) 1999 { 2000 uint64_t txgoff = tx->tx_txg & TXG_MASK; 2001 int old_nlevels = dn->dn_nlevels; 2002 dmu_buf_impl_t *db; 2003 list_t *list; 2004 dbuf_dirty_record_t *new, *dr, *dr_next; 2005 2006 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 2007 2008 ASSERT3U(new_nlevels, >, dn->dn_nlevels); 2009 dn->dn_nlevels = new_nlevels; 2010 2011 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 2012 dn->dn_next_nlevels[txgoff] = new_nlevels; 2013 2014 /* dirty the left indirects */ 2015 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 2016 ASSERT(db != NULL); 2017 new = dbuf_dirty(db, tx); 2018 dbuf_rele(db, FTAG); 2019 2020 /* transfer the dirty records to the new indirect */ 2021 mutex_enter(&dn->dn_mtx); 2022 mutex_enter(&new->dt.di.dr_mtx); 2023 list = &dn->dn_dirty_records[txgoff]; 2024 for (dr = list_head(list); dr; dr = dr_next) { 2025 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 2026 2027 IMPLY(dr->dr_dbuf == NULL, old_nlevels == 1); 2028 if (dr->dr_dbuf == NULL || 2029 (dr->dr_dbuf->db_level == old_nlevels - 1 && 2030 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 2031 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID)) { 2032 list_remove(&dn->dn_dirty_records[txgoff], dr); 2033 list_insert_tail(&new->dt.di.dr_children, dr); 2034 dr->dr_parent = new; 2035 } 2036 } 2037 mutex_exit(&new->dt.di.dr_mtx); 2038 mutex_exit(&dn->dn_mtx); 2039 } 2040 2041 int 2042 dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx) 2043 { 2044 int ret = 0; 2045 2046 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2047 2048 if (dn->dn_nlevels == nlevels) { 2049 ret = 0; 2050 goto out; 2051 } else if (nlevels < dn->dn_nlevels) { 2052 ret = SET_ERROR(EINVAL); 2053 goto out; 2054 } 2055 2056 dnode_set_nlevels_impl(dn, nlevels, tx); 2057 2058 out: 2059 rw_exit(&dn->dn_struct_rwlock); 2060 return (ret); 2061 } 2062 2063 /* read-holding callers must not rely on the lock being continuously held */ 2064 void 2065 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read, 2066 boolean_t force) 2067 { 2068 int epbs, new_nlevels; 2069 uint64_t sz; 2070 2071 ASSERT(blkid != DMU_BONUS_BLKID); 2072 2073 ASSERT(have_read ? 2074 RW_READ_HELD(&dn->dn_struct_rwlock) : 2075 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 2076 2077 /* 2078 * if we have a read-lock, check to see if we need to do any work 2079 * before upgrading to a write-lock. 2080 */ 2081 if (have_read) { 2082 if (blkid <= dn->dn_maxblkid) 2083 return; 2084 2085 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 2086 rw_exit(&dn->dn_struct_rwlock); 2087 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2088 } 2089 } 2090 2091 /* 2092 * Raw sends (indicated by the force flag) require that we take the 2093 * given blkid even if the value is lower than the current value. 2094 */ 2095 if (!force && blkid <= dn->dn_maxblkid) 2096 goto out; 2097 2098 /* 2099 * We use the (otherwise unused) top bit of dn_next_maxblkid[txgoff] 2100 * to indicate that this field is set. This allows us to set the 2101 * maxblkid to 0 on an existing object in dnode_sync(). 2102 */ 2103 dn->dn_maxblkid = blkid; 2104 dn->dn_next_maxblkid[tx->tx_txg & TXG_MASK] = 2105 blkid | DMU_NEXT_MAXBLKID_SET; 2106 2107 /* 2108 * Compute the number of levels necessary to support the new maxblkid. 2109 * Raw sends will ensure nlevels is set correctly for us. 2110 */ 2111 new_nlevels = 1; 2112 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2113 for (sz = dn->dn_nblkptr; 2114 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 2115 new_nlevels++; 2116 2117 ASSERT3U(new_nlevels, <=, DN_MAX_LEVELS); 2118 2119 if (!force) { 2120 if (new_nlevels > dn->dn_nlevels) 2121 dnode_set_nlevels_impl(dn, new_nlevels, tx); 2122 } else { 2123 ASSERT3U(dn->dn_nlevels, >=, new_nlevels); 2124 } 2125 2126 out: 2127 if (have_read) 2128 rw_downgrade(&dn->dn_struct_rwlock); 2129 } 2130 2131 static void 2132 dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx) 2133 { 2134 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG); 2135 if (db != NULL) { 2136 dmu_buf_will_dirty(&db->db, tx); 2137 dbuf_rele(db, FTAG); 2138 } 2139 } 2140 2141 /* 2142 * Dirty all the in-core level-1 dbufs in the range specified by start_blkid 2143 * and end_blkid. 2144 */ 2145 static void 2146 dnode_dirty_l1range(dnode_t *dn, uint64_t start_blkid, uint64_t end_blkid, 2147 dmu_tx_t *tx) 2148 { 2149 dmu_buf_impl_t *db_search; 2150 dmu_buf_impl_t *db; 2151 avl_index_t where; 2152 2153 db_search = kmem_zalloc(sizeof (dmu_buf_impl_t), KM_SLEEP); 2154 2155 mutex_enter(&dn->dn_dbufs_mtx); 2156 2157 db_search->db_level = 1; 2158 db_search->db_blkid = start_blkid + 1; 2159 db_search->db_state = DB_SEARCH; 2160 for (;;) { 2161 2162 db = avl_find(&dn->dn_dbufs, db_search, &where); 2163 if (db == NULL) 2164 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2165 2166 if (db == NULL || db->db_level != 1 || 2167 db->db_blkid >= end_blkid) { 2168 break; 2169 } 2170 2171 /* 2172 * Setup the next blkid we want to search for. 2173 */ 2174 db_search->db_blkid = db->db_blkid + 1; 2175 ASSERT3U(db->db_blkid, >=, start_blkid); 2176 2177 /* 2178 * If the dbuf transitions to DB_EVICTING while we're trying 2179 * to dirty it, then we will be unable to discover it in 2180 * the dbuf hash table. This will result in a call to 2181 * dbuf_create() which needs to acquire the dn_dbufs_mtx 2182 * lock. To avoid a deadlock, we drop the lock before 2183 * dirtying the level-1 dbuf. 2184 */ 2185 mutex_exit(&dn->dn_dbufs_mtx); 2186 dnode_dirty_l1(dn, db->db_blkid, tx); 2187 mutex_enter(&dn->dn_dbufs_mtx); 2188 } 2189 2190 #ifdef ZFS_DEBUG 2191 /* 2192 * Walk all the in-core level-1 dbufs and verify they have been dirtied. 2193 */ 2194 db_search->db_level = 1; 2195 db_search->db_blkid = start_blkid + 1; 2196 db_search->db_state = DB_SEARCH; 2197 db = avl_find(&dn->dn_dbufs, db_search, &where); 2198 if (db == NULL) 2199 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2200 for (; db != NULL; db = AVL_NEXT(&dn->dn_dbufs, db)) { 2201 if (db->db_level != 1 || db->db_blkid >= end_blkid) 2202 break; 2203 if (db->db_state != DB_EVICTING) 2204 ASSERT(db->db_dirtycnt > 0); 2205 } 2206 #endif 2207 kmem_free(db_search, sizeof (dmu_buf_impl_t)); 2208 mutex_exit(&dn->dn_dbufs_mtx); 2209 } 2210 2211 static void 2212 dnode_partial_zero(dnode_t *dn, uint64_t off, uint64_t blkoff, uint64_t len, 2213 dmu_tx_t *tx) 2214 { 2215 dmu_buf_impl_t *db; 2216 int res; 2217 2218 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2219 res = dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off), TRUE, FALSE, 2220 FTAG, &db); 2221 rw_exit(&dn->dn_struct_rwlock); 2222 if (res == 0) { 2223 db_lock_type_t dblt; 2224 boolean_t dirty; 2225 2226 dblt = dmu_buf_lock_parent(db, RW_READER, FTAG); 2227 /* don't dirty if not on disk and not dirty */ 2228 dirty = !list_is_empty(&db->db_dirty_records) || 2229 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr)); 2230 dmu_buf_unlock_parent(db, dblt, FTAG); 2231 if (dirty) { 2232 caddr_t data; 2233 2234 dmu_buf_will_dirty(&db->db, tx); 2235 data = db->db.db_data; 2236 memset(data + blkoff, 0, len); 2237 } 2238 dbuf_rele(db, FTAG); 2239 } 2240 } 2241 2242 void 2243 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 2244 { 2245 uint64_t blkoff, blkid, nblks; 2246 int blksz, blkshift, head, tail; 2247 int trunc = FALSE; 2248 int epbs; 2249 2250 blksz = dn->dn_datablksz; 2251 blkshift = dn->dn_datablkshift; 2252 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2253 2254 if (len == DMU_OBJECT_END) { 2255 len = UINT64_MAX - off; 2256 trunc = TRUE; 2257 } 2258 2259 /* 2260 * First, block align the region to free: 2261 */ 2262 if (ISP2(blksz)) { 2263 head = P2NPHASE(off, blksz); 2264 blkoff = P2PHASE(off, blksz); 2265 if ((off >> blkshift) > dn->dn_maxblkid) 2266 return; 2267 } else { 2268 ASSERT0(dn->dn_maxblkid); 2269 if (off == 0 && len >= blksz) { 2270 /* 2271 * Freeing the whole block; fast-track this request. 2272 */ 2273 blkid = 0; 2274 nblks = 1; 2275 if (dn->dn_nlevels > 1) { 2276 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2277 dnode_dirty_l1(dn, 0, tx); 2278 rw_exit(&dn->dn_struct_rwlock); 2279 } 2280 goto done; 2281 } else if (off >= blksz) { 2282 /* Freeing past end-of-data */ 2283 return; 2284 } else { 2285 /* Freeing part of the block. */ 2286 head = blksz - off; 2287 ASSERT3U(head, >, 0); 2288 } 2289 blkoff = off; 2290 } 2291 /* zero out any partial block data at the start of the range */ 2292 if (head) { 2293 ASSERT3U(blkoff + head, ==, blksz); 2294 if (len < head) 2295 head = len; 2296 dnode_partial_zero(dn, off, blkoff, head, tx); 2297 off += head; 2298 len -= head; 2299 } 2300 2301 /* If the range was less than one block, we're done */ 2302 if (len == 0) 2303 return; 2304 2305 /* If the remaining range is past end of file, we're done */ 2306 if ((off >> blkshift) > dn->dn_maxblkid) 2307 return; 2308 2309 ASSERT(ISP2(blksz)); 2310 if (trunc) 2311 tail = 0; 2312 else 2313 tail = P2PHASE(len, blksz); 2314 2315 ASSERT0(P2PHASE(off, blksz)); 2316 /* zero out any partial block data at the end of the range */ 2317 if (tail) { 2318 if (len < tail) 2319 tail = len; 2320 dnode_partial_zero(dn, off + len, 0, tail, tx); 2321 len -= tail; 2322 } 2323 2324 /* If the range did not include a full block, we are done */ 2325 if (len == 0) 2326 return; 2327 2328 ASSERT(IS_P2ALIGNED(off, blksz)); 2329 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 2330 blkid = off >> blkshift; 2331 nblks = len >> blkshift; 2332 if (trunc) 2333 nblks += 1; 2334 2335 /* 2336 * Dirty all the indirect blocks in this range. Note that only 2337 * the first and last indirect blocks can actually be written 2338 * (if they were partially freed) -- they must be dirtied, even if 2339 * they do not exist on disk yet. The interior blocks will 2340 * be freed by free_children(), so they will not actually be written. 2341 * Even though these interior blocks will not be written, we 2342 * dirty them for two reasons: 2343 * 2344 * - It ensures that the indirect blocks remain in memory until 2345 * syncing context. (They have already been prefetched by 2346 * dmu_tx_hold_free(), so we don't have to worry about reading 2347 * them serially here.) 2348 * 2349 * - The dirty space accounting will put pressure on the txg sync 2350 * mechanism to begin syncing, and to delay transactions if there 2351 * is a large amount of freeing. Even though these indirect 2352 * blocks will not be written, we could need to write the same 2353 * amount of space if we copy the freed BPs into deadlists. 2354 */ 2355 if (dn->dn_nlevels > 1) { 2356 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2357 uint64_t first, last; 2358 2359 first = blkid >> epbs; 2360 dnode_dirty_l1(dn, first, tx); 2361 if (trunc) 2362 last = dn->dn_maxblkid >> epbs; 2363 else 2364 last = (blkid + nblks - 1) >> epbs; 2365 if (last != first) 2366 dnode_dirty_l1(dn, last, tx); 2367 2368 dnode_dirty_l1range(dn, first, last, tx); 2369 2370 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 2371 SPA_BLKPTRSHIFT; 2372 for (uint64_t i = first + 1; i < last; i++) { 2373 /* 2374 * Set i to the blockid of the next non-hole 2375 * level-1 indirect block at or after i. Note 2376 * that dnode_next_offset() operates in terms of 2377 * level-0-equivalent bytes. 2378 */ 2379 uint64_t ibyte = i << shift; 2380 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, 2381 &ibyte, 2, 1, 0); 2382 i = ibyte >> shift; 2383 if (i >= last) 2384 break; 2385 2386 /* 2387 * Normally we should not see an error, either 2388 * from dnode_next_offset() or dbuf_hold_level() 2389 * (except for ESRCH from dnode_next_offset). 2390 * If there is an i/o error, then when we read 2391 * this block in syncing context, it will use 2392 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according 2393 * to the "failmode" property. dnode_next_offset() 2394 * doesn't have a flag to indicate MUSTSUCCEED. 2395 */ 2396 if (err != 0) 2397 break; 2398 2399 dnode_dirty_l1(dn, i, tx); 2400 } 2401 rw_exit(&dn->dn_struct_rwlock); 2402 } 2403 2404 done: 2405 /* 2406 * Add this range to the dnode range list. 2407 * We will finish up this free operation in the syncing phase. 2408 */ 2409 mutex_enter(&dn->dn_mtx); 2410 { 2411 int txgoff = tx->tx_txg & TXG_MASK; 2412 if (dn->dn_free_ranges[txgoff] == NULL) { 2413 dn->dn_free_ranges[txgoff] = 2414 zfs_range_tree_create_flags( 2415 NULL, ZFS_RANGE_SEG64, NULL, 0, 0, 2416 ZFS_RT_F_DYN_NAME, rt_name(dn, "dn_free_ranges")); 2417 } 2418 zfs_range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 2419 zfs_range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 2420 } 2421 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 2422 (u_longlong_t)blkid, (u_longlong_t)nblks, 2423 (u_longlong_t)tx->tx_txg); 2424 mutex_exit(&dn->dn_mtx); 2425 2426 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 2427 dnode_setdirty(dn, tx); 2428 } 2429 2430 static boolean_t 2431 dnode_spill_freed(dnode_t *dn) 2432 { 2433 int i; 2434 2435 mutex_enter(&dn->dn_mtx); 2436 for (i = 0; i < TXG_SIZE; i++) { 2437 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 2438 break; 2439 } 2440 mutex_exit(&dn->dn_mtx); 2441 return (i < TXG_SIZE); 2442 } 2443 2444 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 2445 uint64_t 2446 dnode_block_freed(dnode_t *dn, uint64_t blkid) 2447 { 2448 int i; 2449 2450 if (blkid == DMU_BONUS_BLKID) 2451 return (FALSE); 2452 2453 if (dn->dn_free_txg) 2454 return (TRUE); 2455 2456 if (blkid == DMU_SPILL_BLKID) 2457 return (dnode_spill_freed(dn)); 2458 2459 mutex_enter(&dn->dn_mtx); 2460 for (i = 0; i < TXG_SIZE; i++) { 2461 if (dn->dn_free_ranges[i] != NULL && 2462 zfs_range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 2463 break; 2464 } 2465 mutex_exit(&dn->dn_mtx); 2466 return (i < TXG_SIZE); 2467 } 2468 2469 /* call from syncing context when we actually write/free space for this dnode */ 2470 void 2471 dnode_diduse_space(dnode_t *dn, int64_t delta) 2472 { 2473 uint64_t space; 2474 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 2475 dn, dn->dn_phys, 2476 (u_longlong_t)dn->dn_phys->dn_used, 2477 (longlong_t)delta); 2478 2479 mutex_enter(&dn->dn_mtx); 2480 space = DN_USED_BYTES(dn->dn_phys); 2481 if (delta > 0) { 2482 ASSERT3U(space + delta, >=, space); /* no overflow */ 2483 } else { 2484 ASSERT3U(space, >=, -delta); /* no underflow */ 2485 } 2486 space += delta; 2487 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 2488 ASSERT0((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES)); 2489 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 2490 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 2491 } else { 2492 dn->dn_phys->dn_used = space; 2493 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 2494 } 2495 mutex_exit(&dn->dn_mtx); 2496 } 2497 2498 /* 2499 * Scans a block at the indicated "level" looking for a hole or data, 2500 * depending on 'flags'. 2501 * 2502 * If level > 0, then we are scanning an indirect block looking at its 2503 * pointers. If level == 0, then we are looking at a block of dnodes. 2504 * 2505 * If we don't find what we are looking for in the block, we return ESRCH. 2506 * Otherwise, return with *offset pointing to the beginning (if searching 2507 * forwards) or end (if searching backwards) of the range covered by the 2508 * block pointer we matched on (or dnode). 2509 * 2510 * The basic search algorithm used below by dnode_next_offset() is to 2511 * use this function to search up the block tree (widen the search) until 2512 * we find something (i.e., we don't return ESRCH) and then search back 2513 * down the tree (narrow the search) until we reach our original search 2514 * level. 2515 */ 2516 static int 2517 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 2518 int lvl, uint64_t blkfill, uint64_t txg) 2519 { 2520 dmu_buf_impl_t *db = NULL; 2521 void *data = NULL; 2522 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 2523 uint64_t epb = 1ULL << epbs; 2524 uint64_t minfill, maxfill; 2525 boolean_t hole; 2526 int i, inc, error, span; 2527 2528 ASSERT(RW_LOCK_HELD(&dn->dn_struct_rwlock)); 2529 2530 hole = ((flags & DNODE_FIND_HOLE) != 0); 2531 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 2532 ASSERT(txg == 0 || !hole); 2533 2534 if (lvl == dn->dn_phys->dn_nlevels) { 2535 error = 0; 2536 epb = dn->dn_phys->dn_nblkptr; 2537 data = dn->dn_phys->dn_blkptr; 2538 if (dn->dn_dbuf != NULL) 2539 rw_enter(&dn->dn_dbuf->db_rwlock, RW_READER); 2540 else if (dmu_objset_ds(dn->dn_objset) != NULL) 2541 rrw_enter(&dmu_objset_ds(dn->dn_objset)->ds_bp_rwlock, 2542 RW_READER, FTAG); 2543 } else { 2544 uint64_t blkid = dbuf_whichblock(dn, lvl, *offset); 2545 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FALSE, FTAG, &db); 2546 if (error) { 2547 if (error != ENOENT) 2548 return (error); 2549 if (hole) 2550 return (0); 2551 /* 2552 * This can only happen when we are searching up 2553 * the block tree for data. We don't really need to 2554 * adjust the offset, as we will just end up looking 2555 * at the pointer to this block in its parent, and its 2556 * going to be unallocated, so we will skip over it. 2557 */ 2558 return (SET_ERROR(ESRCH)); 2559 } 2560 error = dbuf_read(db, NULL, 2561 DB_RF_CANFAIL | DB_RF_HAVESTRUCT | 2562 DMU_READ_NO_PREFETCH | DMU_READ_NO_DECRYPT); 2563 if (error) { 2564 dbuf_rele(db, FTAG); 2565 return (error); 2566 } 2567 data = db->db.db_data; 2568 rw_enter(&db->db_rwlock, RW_READER); 2569 } 2570 2571 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 2572 BP_GET_LOGICAL_BIRTH(db->db_blkptr) <= txg || 2573 BP_IS_HOLE(db->db_blkptr))) { 2574 /* 2575 * This can only happen when we are searching up the tree 2576 * and these conditions mean that we need to keep climbing. 2577 */ 2578 error = SET_ERROR(ESRCH); 2579 } else if (lvl == 0) { 2580 dnode_phys_t *dnp = data; 2581 2582 ASSERT(dn->dn_type == DMU_OT_DNODE); 2583 ASSERT(!(flags & DNODE_FIND_BACKWARDS)); 2584 2585 for (i = (*offset >> DNODE_SHIFT) & (blkfill - 1); 2586 i < blkfill; i += dnp[i].dn_extra_slots + 1) { 2587 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 2588 break; 2589 } 2590 2591 if (i == blkfill) 2592 error = SET_ERROR(ESRCH); 2593 2594 *offset = (*offset & ~(DNODE_BLOCK_SIZE - 1)) + 2595 (i << DNODE_SHIFT); 2596 } else { 2597 blkptr_t *bp = data; 2598 uint64_t start = *offset; 2599 span = (lvl - 1) * epbs + dn->dn_datablkshift; 2600 minfill = 0; 2601 maxfill = blkfill << ((lvl - 1) * epbs); 2602 2603 if (hole) 2604 maxfill--; 2605 else 2606 minfill++; 2607 2608 if (span >= 8 * sizeof (*offset)) { 2609 /* This only happens on the highest indirection level */ 2610 ASSERT3U((lvl - 1), ==, dn->dn_phys->dn_nlevels - 1); 2611 *offset = 0; 2612 } else { 2613 *offset = *offset >> span; 2614 } 2615 2616 for (i = BF64_GET(*offset, 0, epbs); 2617 i >= 0 && i < epb; i += inc) { 2618 if (BP_GET_FILL(&bp[i]) >= minfill && 2619 BP_GET_FILL(&bp[i]) <= maxfill && 2620 (hole || BP_GET_LOGICAL_BIRTH(&bp[i]) > txg)) 2621 break; 2622 if (inc > 0 || *offset > 0) 2623 *offset += inc; 2624 } 2625 2626 if (span >= 8 * sizeof (*offset)) { 2627 *offset = start; 2628 } else { 2629 *offset = *offset << span; 2630 } 2631 2632 if (inc < 0) { 2633 /* traversing backwards; position offset at the end */ 2634 if (span < 8 * sizeof (*offset)) 2635 *offset = MIN(*offset + (1ULL << span) - 1, 2636 start); 2637 } else if (*offset < start) { 2638 *offset = start; 2639 } 2640 if (i < 0 || i >= epb) 2641 error = SET_ERROR(ESRCH); 2642 } 2643 2644 if (db != NULL) { 2645 rw_exit(&db->db_rwlock); 2646 dbuf_rele(db, FTAG); 2647 } else { 2648 if (dn->dn_dbuf != NULL) 2649 rw_exit(&dn->dn_dbuf->db_rwlock); 2650 else if (dmu_objset_ds(dn->dn_objset) != NULL) 2651 rrw_exit(&dmu_objset_ds(dn->dn_objset)->ds_bp_rwlock, 2652 FTAG); 2653 } 2654 2655 return (error); 2656 } 2657 2658 /* 2659 * Find the next hole, data, or sparse region at or after *offset. 2660 * The value 'blkfill' tells us how many items we expect to find 2661 * in an L0 data block; this value is 1 for normal objects, 2662 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 2663 * DNODES_PER_BLOCK when searching for sparse regions thereof. 2664 * 2665 * Examples: 2666 * 2667 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 2668 * Finds the next/previous hole/data in a file. 2669 * Used in dmu_offset_next(). 2670 * 2671 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 2672 * Finds the next free/allocated dnode an objset's meta-dnode. 2673 * Only finds objects that have new contents since txg (ie. 2674 * bonus buffer changes and content removal are ignored). 2675 * Used in dmu_object_next(). 2676 * 2677 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 2678 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 2679 * Used in dmu_object_alloc(). 2680 */ 2681 int 2682 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 2683 int minlvl, uint64_t blkfill, uint64_t txg) 2684 { 2685 uint64_t initial_offset = *offset; 2686 int lvl, maxlvl; 2687 int error = 0; 2688 2689 if (!(flags & DNODE_FIND_HAVELOCK)) 2690 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2691 2692 if (dn->dn_phys->dn_nlevels == 0) { 2693 error = SET_ERROR(ESRCH); 2694 goto out; 2695 } 2696 2697 if (dn->dn_datablkshift == 0) { 2698 if (*offset < dn->dn_datablksz) { 2699 if (flags & DNODE_FIND_HOLE) 2700 *offset = dn->dn_datablksz; 2701 } else { 2702 error = SET_ERROR(ESRCH); 2703 } 2704 goto out; 2705 } 2706 2707 maxlvl = dn->dn_phys->dn_nlevels; 2708 2709 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 2710 error = dnode_next_offset_level(dn, 2711 flags, offset, lvl, blkfill, txg); 2712 if (error != ESRCH) 2713 break; 2714 } 2715 2716 while (error == 0 && --lvl >= minlvl) { 2717 error = dnode_next_offset_level(dn, 2718 flags, offset, lvl, blkfill, txg); 2719 } 2720 2721 /* 2722 * There's always a "virtual hole" at the end of the object, even 2723 * if all BP's which physically exist are non-holes. 2724 */ 2725 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 && 2726 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) { 2727 error = 0; 2728 } 2729 2730 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 2731 initial_offset < *offset : initial_offset > *offset)) 2732 error = SET_ERROR(ESRCH); 2733 out: 2734 if (!(flags & DNODE_FIND_HAVELOCK)) 2735 rw_exit(&dn->dn_struct_rwlock); 2736 2737 return (error); 2738 } 2739 2740 #if defined(_KERNEL) 2741 EXPORT_SYMBOL(dnode_hold); 2742 EXPORT_SYMBOL(dnode_rele); 2743 EXPORT_SYMBOL(dnode_set_nlevels); 2744 EXPORT_SYMBOL(dnode_set_blksz); 2745 EXPORT_SYMBOL(dnode_free_range); 2746 EXPORT_SYMBOL(dnode_evict_dbufs); 2747 EXPORT_SYMBOL(dnode_evict_bonus); 2748 #endif 2749 2750 ZFS_MODULE_PARAM(zfs, zfs_, default_bs, INT, ZMOD_RW, 2751 "Default dnode block shift"); 2752 ZFS_MODULE_PARAM(zfs, zfs_, default_ibs, INT, ZMOD_RW, 2753 "Default dnode indirect block shift"); 2754