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 https://opensource.org/licenses/CDDL-1.0. 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, 2020 by Delphix. All rights reserved. 24 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. 25 */ 26 27 #include <sys/zfs_context.h> 28 #include <sys/dbuf.h> 29 #include <sys/dnode.h> 30 #include <sys/dmu.h> 31 #include <sys/dmu_impl.h> 32 #include <sys/dmu_tx.h> 33 #include <sys/dmu_objset.h> 34 #include <sys/dsl_dir.h> 35 #include <sys/dsl_dataset.h> 36 #include <sys/spa.h> 37 #include <sys/zio.h> 38 #include <sys/dmu_zfetch.h> 39 #include <sys/range_tree.h> 40 #include <sys/trace_zfs.h> 41 #include <sys/zfs_project.h> 42 43 dnode_stats_t dnode_stats = { 44 { "dnode_hold_dbuf_hold", KSTAT_DATA_UINT64 }, 45 { "dnode_hold_dbuf_read", KSTAT_DATA_UINT64 }, 46 { "dnode_hold_alloc_hits", KSTAT_DATA_UINT64 }, 47 { "dnode_hold_alloc_misses", KSTAT_DATA_UINT64 }, 48 { "dnode_hold_alloc_interior", KSTAT_DATA_UINT64 }, 49 { "dnode_hold_alloc_lock_retry", KSTAT_DATA_UINT64 }, 50 { "dnode_hold_alloc_lock_misses", KSTAT_DATA_UINT64 }, 51 { "dnode_hold_alloc_type_none", KSTAT_DATA_UINT64 }, 52 { "dnode_hold_free_hits", KSTAT_DATA_UINT64 }, 53 { "dnode_hold_free_misses", KSTAT_DATA_UINT64 }, 54 { "dnode_hold_free_lock_misses", KSTAT_DATA_UINT64 }, 55 { "dnode_hold_free_lock_retry", KSTAT_DATA_UINT64 }, 56 { "dnode_hold_free_overflow", KSTAT_DATA_UINT64 }, 57 { "dnode_hold_free_refcount", KSTAT_DATA_UINT64 }, 58 { "dnode_free_interior_lock_retry", KSTAT_DATA_UINT64 }, 59 { "dnode_allocate", KSTAT_DATA_UINT64 }, 60 { "dnode_reallocate", KSTAT_DATA_UINT64 }, 61 { "dnode_buf_evict", KSTAT_DATA_UINT64 }, 62 { "dnode_alloc_next_chunk", KSTAT_DATA_UINT64 }, 63 { "dnode_alloc_race", KSTAT_DATA_UINT64 }, 64 { "dnode_alloc_next_block", KSTAT_DATA_UINT64 }, 65 { "dnode_move_invalid", KSTAT_DATA_UINT64 }, 66 { "dnode_move_recheck1", KSTAT_DATA_UINT64 }, 67 { "dnode_move_recheck2", KSTAT_DATA_UINT64 }, 68 { "dnode_move_special", KSTAT_DATA_UINT64 }, 69 { "dnode_move_handle", KSTAT_DATA_UINT64 }, 70 { "dnode_move_rwlock", KSTAT_DATA_UINT64 }, 71 { "dnode_move_active", KSTAT_DATA_UINT64 }, 72 }; 73 74 dnode_sums_t dnode_sums; 75 76 static kstat_t *dnode_ksp; 77 static kmem_cache_t *dnode_cache; 78 79 static dnode_phys_t dnode_phys_zero __maybe_unused; 80 81 int zfs_default_bs = SPA_MINBLOCKSHIFT; 82 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 83 84 #ifdef _KERNEL 85 static kmem_cbrc_t dnode_move(void *, void *, size_t, void *); 86 #endif /* _KERNEL */ 87 88 static int 89 dbuf_compare(const void *x1, const void *x2) 90 { 91 const dmu_buf_impl_t *d1 = x1; 92 const dmu_buf_impl_t *d2 = x2; 93 94 int cmp = TREE_CMP(d1->db_level, d2->db_level); 95 if (likely(cmp)) 96 return (cmp); 97 98 cmp = TREE_CMP(d1->db_blkid, d2->db_blkid); 99 if (likely(cmp)) 100 return (cmp); 101 102 if (d1->db_state == DB_MARKER) { 103 ASSERT3S(d2->db_state, !=, DB_MARKER); 104 return (TREE_PCMP(d1->db_parent, d2)); 105 } else if (d2->db_state == DB_MARKER) { 106 ASSERT3S(d1->db_state, !=, DB_MARKER); 107 return (TREE_PCMP(d1, d2->db_parent)); 108 } 109 110 if (d1->db_state == DB_SEARCH) { 111 ASSERT3S(d2->db_state, !=, DB_SEARCH); 112 return (-1); 113 } else if (d2->db_state == DB_SEARCH) { 114 ASSERT3S(d1->db_state, !=, DB_SEARCH); 115 return (1); 116 } 117 118 return (TREE_PCMP(d1, d2)); 119 } 120 121 static int 122 dnode_cons(void *arg, void *unused, int kmflag) 123 { 124 (void) unused, (void) kmflag; 125 dnode_t *dn = arg; 126 127 rw_init(&dn->dn_struct_rwlock, NULL, RW_NOLOCKDEP, NULL); 128 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 129 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 130 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 131 cv_init(&dn->dn_nodnholds, NULL, CV_DEFAULT, NULL); 132 133 /* 134 * Every dbuf has a reference, and dropping a tracked reference is 135 * O(number of references), so don't track dn_holds. 136 */ 137 zfs_refcount_create_untracked(&dn->dn_holds); 138 zfs_refcount_create(&dn->dn_tx_holds); 139 list_link_init(&dn->dn_link); 140 141 memset(dn->dn_next_type, 0, sizeof (dn->dn_next_type)); 142 memset(dn->dn_next_nblkptr, 0, sizeof (dn->dn_next_nblkptr)); 143 memset(dn->dn_next_nlevels, 0, sizeof (dn->dn_next_nlevels)); 144 memset(dn->dn_next_indblkshift, 0, sizeof (dn->dn_next_indblkshift)); 145 memset(dn->dn_next_bonustype, 0, sizeof (dn->dn_next_bonustype)); 146 memset(dn->dn_rm_spillblk, 0, sizeof (dn->dn_rm_spillblk)); 147 memset(dn->dn_next_bonuslen, 0, sizeof (dn->dn_next_bonuslen)); 148 memset(dn->dn_next_blksz, 0, sizeof (dn->dn_next_blksz)); 149 memset(dn->dn_next_maxblkid, 0, sizeof (dn->dn_next_maxblkid)); 150 151 for (int i = 0; i < TXG_SIZE; i++) { 152 multilist_link_init(&dn->dn_dirty_link[i]); 153 dn->dn_free_ranges[i] = NULL; 154 list_create(&dn->dn_dirty_records[i], 155 sizeof (dbuf_dirty_record_t), 156 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 157 } 158 159 dn->dn_allocated_txg = 0; 160 dn->dn_free_txg = 0; 161 dn->dn_assigned_txg = 0; 162 dn->dn_dirty_txg = 0; 163 dn->dn_dirtyctx = 0; 164 dn->dn_dirtyctx_firstset = NULL; 165 dn->dn_bonus = NULL; 166 dn->dn_have_spill = B_FALSE; 167 dn->dn_zio = NULL; 168 dn->dn_oldused = 0; 169 dn->dn_oldflags = 0; 170 dn->dn_olduid = 0; 171 dn->dn_oldgid = 0; 172 dn->dn_oldprojid = ZFS_DEFAULT_PROJID; 173 dn->dn_newuid = 0; 174 dn->dn_newgid = 0; 175 dn->dn_newprojid = ZFS_DEFAULT_PROJID; 176 dn->dn_id_flags = 0; 177 178 dn->dn_dbufs_count = 0; 179 avl_create(&dn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 180 offsetof(dmu_buf_impl_t, db_link)); 181 182 dn->dn_moved = 0; 183 return (0); 184 } 185 186 static void 187 dnode_dest(void *arg, void *unused) 188 { 189 (void) unused; 190 dnode_t *dn = arg; 191 192 rw_destroy(&dn->dn_struct_rwlock); 193 mutex_destroy(&dn->dn_mtx); 194 mutex_destroy(&dn->dn_dbufs_mtx); 195 cv_destroy(&dn->dn_notxholds); 196 cv_destroy(&dn->dn_nodnholds); 197 zfs_refcount_destroy(&dn->dn_holds); 198 zfs_refcount_destroy(&dn->dn_tx_holds); 199 ASSERT(!list_link_active(&dn->dn_link)); 200 201 for (int i = 0; i < TXG_SIZE; i++) { 202 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i])); 203 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 204 list_destroy(&dn->dn_dirty_records[i]); 205 ASSERT0(dn->dn_next_nblkptr[i]); 206 ASSERT0(dn->dn_next_nlevels[i]); 207 ASSERT0(dn->dn_next_indblkshift[i]); 208 ASSERT0(dn->dn_next_bonustype[i]); 209 ASSERT0(dn->dn_rm_spillblk[i]); 210 ASSERT0(dn->dn_next_bonuslen[i]); 211 ASSERT0(dn->dn_next_blksz[i]); 212 ASSERT0(dn->dn_next_maxblkid[i]); 213 } 214 215 ASSERT0(dn->dn_allocated_txg); 216 ASSERT0(dn->dn_free_txg); 217 ASSERT0(dn->dn_assigned_txg); 218 ASSERT0(dn->dn_dirty_txg); 219 ASSERT0(dn->dn_dirtyctx); 220 ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL); 221 ASSERT3P(dn->dn_bonus, ==, NULL); 222 ASSERT(!dn->dn_have_spill); 223 ASSERT3P(dn->dn_zio, ==, NULL); 224 ASSERT0(dn->dn_oldused); 225 ASSERT0(dn->dn_oldflags); 226 ASSERT0(dn->dn_olduid); 227 ASSERT0(dn->dn_oldgid); 228 ASSERT0(dn->dn_oldprojid); 229 ASSERT0(dn->dn_newuid); 230 ASSERT0(dn->dn_newgid); 231 ASSERT0(dn->dn_newprojid); 232 ASSERT0(dn->dn_id_flags); 233 234 ASSERT0(dn->dn_dbufs_count); 235 avl_destroy(&dn->dn_dbufs); 236 } 237 238 static int 239 dnode_kstats_update(kstat_t *ksp, int rw) 240 { 241 dnode_stats_t *ds = ksp->ks_data; 242 243 if (rw == KSTAT_WRITE) 244 return (EACCES); 245 ds->dnode_hold_dbuf_hold.value.ui64 = 246 wmsum_value(&dnode_sums.dnode_hold_dbuf_hold); 247 ds->dnode_hold_dbuf_read.value.ui64 = 248 wmsum_value(&dnode_sums.dnode_hold_dbuf_read); 249 ds->dnode_hold_alloc_hits.value.ui64 = 250 wmsum_value(&dnode_sums.dnode_hold_alloc_hits); 251 ds->dnode_hold_alloc_misses.value.ui64 = 252 wmsum_value(&dnode_sums.dnode_hold_alloc_misses); 253 ds->dnode_hold_alloc_interior.value.ui64 = 254 wmsum_value(&dnode_sums.dnode_hold_alloc_interior); 255 ds->dnode_hold_alloc_lock_retry.value.ui64 = 256 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_retry); 257 ds->dnode_hold_alloc_lock_misses.value.ui64 = 258 wmsum_value(&dnode_sums.dnode_hold_alloc_lock_misses); 259 ds->dnode_hold_alloc_type_none.value.ui64 = 260 wmsum_value(&dnode_sums.dnode_hold_alloc_type_none); 261 ds->dnode_hold_free_hits.value.ui64 = 262 wmsum_value(&dnode_sums.dnode_hold_free_hits); 263 ds->dnode_hold_free_misses.value.ui64 = 264 wmsum_value(&dnode_sums.dnode_hold_free_misses); 265 ds->dnode_hold_free_lock_misses.value.ui64 = 266 wmsum_value(&dnode_sums.dnode_hold_free_lock_misses); 267 ds->dnode_hold_free_lock_retry.value.ui64 = 268 wmsum_value(&dnode_sums.dnode_hold_free_lock_retry); 269 ds->dnode_hold_free_refcount.value.ui64 = 270 wmsum_value(&dnode_sums.dnode_hold_free_refcount); 271 ds->dnode_hold_free_overflow.value.ui64 = 272 wmsum_value(&dnode_sums.dnode_hold_free_overflow); 273 ds->dnode_free_interior_lock_retry.value.ui64 = 274 wmsum_value(&dnode_sums.dnode_free_interior_lock_retry); 275 ds->dnode_allocate.value.ui64 = 276 wmsum_value(&dnode_sums.dnode_allocate); 277 ds->dnode_reallocate.value.ui64 = 278 wmsum_value(&dnode_sums.dnode_reallocate); 279 ds->dnode_buf_evict.value.ui64 = 280 wmsum_value(&dnode_sums.dnode_buf_evict); 281 ds->dnode_alloc_next_chunk.value.ui64 = 282 wmsum_value(&dnode_sums.dnode_alloc_next_chunk); 283 ds->dnode_alloc_race.value.ui64 = 284 wmsum_value(&dnode_sums.dnode_alloc_race); 285 ds->dnode_alloc_next_block.value.ui64 = 286 wmsum_value(&dnode_sums.dnode_alloc_next_block); 287 ds->dnode_move_invalid.value.ui64 = 288 wmsum_value(&dnode_sums.dnode_move_invalid); 289 ds->dnode_move_recheck1.value.ui64 = 290 wmsum_value(&dnode_sums.dnode_move_recheck1); 291 ds->dnode_move_recheck2.value.ui64 = 292 wmsum_value(&dnode_sums.dnode_move_recheck2); 293 ds->dnode_move_special.value.ui64 = 294 wmsum_value(&dnode_sums.dnode_move_special); 295 ds->dnode_move_handle.value.ui64 = 296 wmsum_value(&dnode_sums.dnode_move_handle); 297 ds->dnode_move_rwlock.value.ui64 = 298 wmsum_value(&dnode_sums.dnode_move_rwlock); 299 ds->dnode_move_active.value.ui64 = 300 wmsum_value(&dnode_sums.dnode_move_active); 301 return (0); 302 } 303 304 void 305 dnode_init(void) 306 { 307 ASSERT(dnode_cache == NULL); 308 dnode_cache = kmem_cache_create("dnode_t", sizeof (dnode_t), 309 0, dnode_cons, dnode_dest, NULL, NULL, NULL, KMC_RECLAIMABLE); 310 kmem_cache_set_move(dnode_cache, dnode_move); 311 312 wmsum_init(&dnode_sums.dnode_hold_dbuf_hold, 0); 313 wmsum_init(&dnode_sums.dnode_hold_dbuf_read, 0); 314 wmsum_init(&dnode_sums.dnode_hold_alloc_hits, 0); 315 wmsum_init(&dnode_sums.dnode_hold_alloc_misses, 0); 316 wmsum_init(&dnode_sums.dnode_hold_alloc_interior, 0); 317 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_retry, 0); 318 wmsum_init(&dnode_sums.dnode_hold_alloc_lock_misses, 0); 319 wmsum_init(&dnode_sums.dnode_hold_alloc_type_none, 0); 320 wmsum_init(&dnode_sums.dnode_hold_free_hits, 0); 321 wmsum_init(&dnode_sums.dnode_hold_free_misses, 0); 322 wmsum_init(&dnode_sums.dnode_hold_free_lock_misses, 0); 323 wmsum_init(&dnode_sums.dnode_hold_free_lock_retry, 0); 324 wmsum_init(&dnode_sums.dnode_hold_free_refcount, 0); 325 wmsum_init(&dnode_sums.dnode_hold_free_overflow, 0); 326 wmsum_init(&dnode_sums.dnode_free_interior_lock_retry, 0); 327 wmsum_init(&dnode_sums.dnode_allocate, 0); 328 wmsum_init(&dnode_sums.dnode_reallocate, 0); 329 wmsum_init(&dnode_sums.dnode_buf_evict, 0); 330 wmsum_init(&dnode_sums.dnode_alloc_next_chunk, 0); 331 wmsum_init(&dnode_sums.dnode_alloc_race, 0); 332 wmsum_init(&dnode_sums.dnode_alloc_next_block, 0); 333 wmsum_init(&dnode_sums.dnode_move_invalid, 0); 334 wmsum_init(&dnode_sums.dnode_move_recheck1, 0); 335 wmsum_init(&dnode_sums.dnode_move_recheck2, 0); 336 wmsum_init(&dnode_sums.dnode_move_special, 0); 337 wmsum_init(&dnode_sums.dnode_move_handle, 0); 338 wmsum_init(&dnode_sums.dnode_move_rwlock, 0); 339 wmsum_init(&dnode_sums.dnode_move_active, 0); 340 341 dnode_ksp = kstat_create("zfs", 0, "dnodestats", "misc", 342 KSTAT_TYPE_NAMED, sizeof (dnode_stats) / sizeof (kstat_named_t), 343 KSTAT_FLAG_VIRTUAL); 344 if (dnode_ksp != NULL) { 345 dnode_ksp->ks_data = &dnode_stats; 346 dnode_ksp->ks_update = dnode_kstats_update; 347 kstat_install(dnode_ksp); 348 } 349 } 350 351 void 352 dnode_fini(void) 353 { 354 if (dnode_ksp != NULL) { 355 kstat_delete(dnode_ksp); 356 dnode_ksp = NULL; 357 } 358 359 wmsum_fini(&dnode_sums.dnode_hold_dbuf_hold); 360 wmsum_fini(&dnode_sums.dnode_hold_dbuf_read); 361 wmsum_fini(&dnode_sums.dnode_hold_alloc_hits); 362 wmsum_fini(&dnode_sums.dnode_hold_alloc_misses); 363 wmsum_fini(&dnode_sums.dnode_hold_alloc_interior); 364 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_retry); 365 wmsum_fini(&dnode_sums.dnode_hold_alloc_lock_misses); 366 wmsum_fini(&dnode_sums.dnode_hold_alloc_type_none); 367 wmsum_fini(&dnode_sums.dnode_hold_free_hits); 368 wmsum_fini(&dnode_sums.dnode_hold_free_misses); 369 wmsum_fini(&dnode_sums.dnode_hold_free_lock_misses); 370 wmsum_fini(&dnode_sums.dnode_hold_free_lock_retry); 371 wmsum_fini(&dnode_sums.dnode_hold_free_refcount); 372 wmsum_fini(&dnode_sums.dnode_hold_free_overflow); 373 wmsum_fini(&dnode_sums.dnode_free_interior_lock_retry); 374 wmsum_fini(&dnode_sums.dnode_allocate); 375 wmsum_fini(&dnode_sums.dnode_reallocate); 376 wmsum_fini(&dnode_sums.dnode_buf_evict); 377 wmsum_fini(&dnode_sums.dnode_alloc_next_chunk); 378 wmsum_fini(&dnode_sums.dnode_alloc_race); 379 wmsum_fini(&dnode_sums.dnode_alloc_next_block); 380 wmsum_fini(&dnode_sums.dnode_move_invalid); 381 wmsum_fini(&dnode_sums.dnode_move_recheck1); 382 wmsum_fini(&dnode_sums.dnode_move_recheck2); 383 wmsum_fini(&dnode_sums.dnode_move_special); 384 wmsum_fini(&dnode_sums.dnode_move_handle); 385 wmsum_fini(&dnode_sums.dnode_move_rwlock); 386 wmsum_fini(&dnode_sums.dnode_move_active); 387 388 kmem_cache_destroy(dnode_cache); 389 dnode_cache = NULL; 390 } 391 392 393 #ifdef ZFS_DEBUG 394 void 395 dnode_verify(dnode_t *dn) 396 { 397 int drop_struct_lock = FALSE; 398 399 ASSERT(dn->dn_phys); 400 ASSERT(dn->dn_objset); 401 ASSERT(dn->dn_handle->dnh_dnode == dn); 402 403 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 404 405 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 406 return; 407 408 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 409 rw_enter(&dn->dn_struct_rwlock, RW_READER); 410 drop_struct_lock = TRUE; 411 } 412 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 413 int i; 414 int max_bonuslen = DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots); 415 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 416 if (dn->dn_datablkshift) { 417 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 418 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 419 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 420 } 421 ASSERT3U(dn->dn_nlevels, <=, 30); 422 ASSERT(DMU_OT_IS_VALID(dn->dn_type)); 423 ASSERT3U(dn->dn_nblkptr, >=, 1); 424 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 425 ASSERT3U(dn->dn_bonuslen, <=, max_bonuslen); 426 ASSERT3U(dn->dn_datablksz, ==, 427 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 428 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 429 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 430 dn->dn_bonuslen, <=, max_bonuslen); 431 for (i = 0; i < TXG_SIZE; i++) { 432 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 433 } 434 } 435 if (dn->dn_phys->dn_type != DMU_OT_NONE) 436 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 437 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 438 if (dn->dn_dbuf != NULL) { 439 ASSERT3P(dn->dn_phys, ==, 440 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 441 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 442 } 443 if (drop_struct_lock) 444 rw_exit(&dn->dn_struct_rwlock); 445 } 446 #endif 447 448 void 449 dnode_byteswap(dnode_phys_t *dnp) 450 { 451 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 452 int i; 453 454 if (dnp->dn_type == DMU_OT_NONE) { 455 memset(dnp, 0, sizeof (dnode_phys_t)); 456 return; 457 } 458 459 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 460 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 461 dnp->dn_extra_slots = BSWAP_8(dnp->dn_extra_slots); 462 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 463 dnp->dn_used = BSWAP_64(dnp->dn_used); 464 465 /* 466 * dn_nblkptr is only one byte, so it's OK to read it in either 467 * byte order. We can't read dn_bouslen. 468 */ 469 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 470 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 471 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 472 buf64[i] = BSWAP_64(buf64[i]); 473 474 /* 475 * OK to check dn_bonuslen for zero, because it won't matter if 476 * we have the wrong byte order. This is necessary because the 477 * dnode dnode is smaller than a regular dnode. 478 */ 479 if (dnp->dn_bonuslen != 0) { 480 dmu_object_byteswap_t byteswap; 481 ASSERT(DMU_OT_IS_VALID(dnp->dn_bonustype)); 482 byteswap = DMU_OT_BYTESWAP(dnp->dn_bonustype); 483 dmu_ot_byteswap[byteswap].ob_func(DN_BONUS(dnp), 484 DN_MAX_BONUS_LEN(dnp)); 485 } 486 487 /* Swap SPILL block if we have one */ 488 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 489 byteswap_uint64_array(DN_SPILL_BLKPTR(dnp), sizeof (blkptr_t)); 490 } 491 492 void 493 dnode_buf_byteswap(void *vbuf, size_t size) 494 { 495 int i = 0; 496 497 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 498 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 499 500 while (i < size) { 501 dnode_phys_t *dnp = (void *)(((char *)vbuf) + i); 502 dnode_byteswap(dnp); 503 504 i += DNODE_MIN_SIZE; 505 if (dnp->dn_type != DMU_OT_NONE) 506 i += dnp->dn_extra_slots * DNODE_MIN_SIZE; 507 } 508 } 509 510 void 511 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 512 { 513 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 514 515 dnode_setdirty(dn, tx); 516 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 517 ASSERT3U(newsize, <=, DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) - 518 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 519 520 if (newsize < dn->dn_bonuslen) { 521 /* clear any data after the end of the new size */ 522 size_t diff = dn->dn_bonuslen - newsize; 523 char *data_end = ((char *)dn->dn_bonus->db.db_data) + newsize; 524 memset(data_end, 0, diff); 525 } 526 527 dn->dn_bonuslen = newsize; 528 if (newsize == 0) 529 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 530 else 531 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 532 rw_exit(&dn->dn_struct_rwlock); 533 } 534 535 void 536 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 537 { 538 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 539 dnode_setdirty(dn, tx); 540 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 541 dn->dn_bonustype = newtype; 542 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 543 rw_exit(&dn->dn_struct_rwlock); 544 } 545 546 void 547 dnode_set_storage_type(dnode_t *dn, dmu_object_type_t newtype) 548 { 549 /* 550 * This is not in the dnode_phys, but it should be, and perhaps one day 551 * will. For now we require it be set after taking a hold. 552 */ 553 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 554 dn->dn_storage_type = newtype; 555 } 556 557 void 558 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 559 { 560 ASSERT3U(zfs_refcount_count(&dn->dn_holds), >=, 1); 561 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 562 dnode_setdirty(dn, tx); 563 dn->dn_rm_spillblk[tx->tx_txg & TXG_MASK] = DN_KILL_SPILLBLK; 564 dn->dn_have_spill = B_FALSE; 565 } 566 567 static void 568 dnode_setdblksz(dnode_t *dn, int size) 569 { 570 ASSERT0(P2PHASE(size, SPA_MINBLOCKSIZE)); 571 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 572 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 573 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 574 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 575 dn->dn_datablksz = size; 576 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 577 dn->dn_datablkshift = ISP2(size) ? highbit64(size - 1) : 0; 578 } 579 580 static dnode_t * 581 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 582 uint64_t object, dnode_handle_t *dnh) 583 { 584 dnode_t *dn; 585 586 dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 587 dn->dn_moved = 0; 588 589 /* 590 * Defer setting dn_objset until the dnode is ready to be a candidate 591 * for the dnode_move() callback. 592 */ 593 dn->dn_object = object; 594 dn->dn_dbuf = db; 595 dn->dn_handle = dnh; 596 dn->dn_phys = dnp; 597 598 if (dnp->dn_datablkszsec) { 599 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 600 } else { 601 dn->dn_datablksz = 0; 602 dn->dn_datablkszsec = 0; 603 dn->dn_datablkshift = 0; 604 } 605 dn->dn_indblkshift = dnp->dn_indblkshift; 606 dn->dn_nlevels = dnp->dn_nlevels; 607 dn->dn_type = dnp->dn_type; 608 dn->dn_nblkptr = dnp->dn_nblkptr; 609 dn->dn_checksum = dnp->dn_checksum; 610 dn->dn_compress = dnp->dn_compress; 611 dn->dn_bonustype = dnp->dn_bonustype; 612 dn->dn_bonuslen = dnp->dn_bonuslen; 613 dn->dn_num_slots = dnp->dn_extra_slots + 1; 614 dn->dn_maxblkid = dnp->dn_maxblkid; 615 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 616 dn->dn_id_flags = 0; 617 618 dn->dn_storage_type = DMU_OT_NONE; 619 620 dmu_zfetch_init(&dn->dn_zfetch, dn); 621 622 ASSERT(DMU_OT_IS_VALID(dn->dn_phys->dn_type)); 623 ASSERT(zrl_is_locked(&dnh->dnh_zrlock)); 624 ASSERT(!DN_SLOT_IS_PTR(dnh->dnh_dnode)); 625 626 mutex_enter(&os->os_lock); 627 628 /* 629 * Exclude special dnodes from os_dnodes so an empty os_dnodes 630 * signifies that the special dnodes have no references from 631 * their children (the entries in os_dnodes). This allows 632 * dnode_destroy() to easily determine if the last child has 633 * been removed and then complete eviction of the objset. 634 */ 635 if (!DMU_OBJECT_IS_SPECIAL(object)) 636 list_insert_head(&os->os_dnodes, dn); 637 membar_producer(); 638 639 /* 640 * Everything else must be valid before assigning dn_objset 641 * makes the dnode eligible for dnode_move(). 642 */ 643 dn->dn_objset = os; 644 645 dnh->dnh_dnode = dn; 646 mutex_exit(&os->os_lock); 647 648 arc_space_consume(sizeof (dnode_t), ARC_SPACE_DNODE); 649 650 return (dn); 651 } 652 653 /* 654 * Caller must be holding the dnode handle, which is released upon return. 655 */ 656 static void 657 dnode_destroy(dnode_t *dn) 658 { 659 objset_t *os = dn->dn_objset; 660 boolean_t complete_os_eviction = B_FALSE; 661 662 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 663 664 mutex_enter(&os->os_lock); 665 POINTER_INVALIDATE(&dn->dn_objset); 666 if (!DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 667 list_remove(&os->os_dnodes, dn); 668 complete_os_eviction = 669 list_is_empty(&os->os_dnodes) && 670 list_link_active(&os->os_evicting_node); 671 } 672 mutex_exit(&os->os_lock); 673 674 /* the dnode can no longer move, so we can release the handle */ 675 if (!zrl_is_locked(&dn->dn_handle->dnh_zrlock)) 676 zrl_remove(&dn->dn_handle->dnh_zrlock); 677 678 dn->dn_allocated_txg = 0; 679 dn->dn_free_txg = 0; 680 dn->dn_assigned_txg = 0; 681 dn->dn_dirty_txg = 0; 682 683 dn->dn_dirtyctx = 0; 684 dn->dn_dirtyctx_firstset = NULL; 685 if (dn->dn_bonus != NULL) { 686 mutex_enter(&dn->dn_bonus->db_mtx); 687 dbuf_destroy(dn->dn_bonus); 688 dn->dn_bonus = NULL; 689 } 690 dn->dn_zio = NULL; 691 692 dn->dn_have_spill = B_FALSE; 693 dn->dn_oldused = 0; 694 dn->dn_oldflags = 0; 695 dn->dn_olduid = 0; 696 dn->dn_oldgid = 0; 697 dn->dn_oldprojid = ZFS_DEFAULT_PROJID; 698 dn->dn_newuid = 0; 699 dn->dn_newgid = 0; 700 dn->dn_newprojid = ZFS_DEFAULT_PROJID; 701 dn->dn_id_flags = 0; 702 703 dn->dn_storage_type = DMU_OT_NONE; 704 705 dmu_zfetch_fini(&dn->dn_zfetch); 706 kmem_cache_free(dnode_cache, dn); 707 arc_space_return(sizeof (dnode_t), ARC_SPACE_DNODE); 708 709 if (complete_os_eviction) 710 dmu_objset_evict_done(os); 711 } 712 713 void 714 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 715 dmu_object_type_t bonustype, int bonuslen, int dn_slots, dmu_tx_t *tx) 716 { 717 int i; 718 719 ASSERT3U(dn_slots, >, 0); 720 ASSERT3U(dn_slots << DNODE_SHIFT, <=, 721 spa_maxdnodesize(dmu_objset_spa(dn->dn_objset))); 722 ASSERT3U(blocksize, <=, 723 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 724 if (blocksize == 0) 725 blocksize = 1 << zfs_default_bs; 726 else 727 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 728 729 if (ibs == 0) 730 ibs = zfs_default_ibs; 731 732 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 733 734 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d dn_slots=%d\n", 735 dn->dn_objset, (u_longlong_t)dn->dn_object, 736 (u_longlong_t)tx->tx_txg, blocksize, ibs, dn_slots); 737 DNODE_STAT_BUMP(dnode_allocate); 738 739 ASSERT(dn->dn_type == DMU_OT_NONE); 740 ASSERT0(memcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t))); 741 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 742 ASSERT(ot != DMU_OT_NONE); 743 ASSERT(DMU_OT_IS_VALID(ot)); 744 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 745 (bonustype == DMU_OT_SA && bonuslen == 0) || 746 (bonustype == DMU_OTN_UINT64_METADATA && bonuslen == 0) || 747 (bonustype != DMU_OT_NONE && bonuslen != 0)); 748 ASSERT(DMU_OT_IS_VALID(bonustype)); 749 ASSERT3U(bonuslen, <=, DN_SLOTS_TO_BONUSLEN(dn_slots)); 750 ASSERT(dn->dn_type == DMU_OT_NONE); 751 ASSERT0(dn->dn_maxblkid); 752 ASSERT0(dn->dn_allocated_txg); 753 ASSERT0(dn->dn_assigned_txg); 754 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 755 ASSERT3U(zfs_refcount_count(&dn->dn_holds), <=, 1); 756 ASSERT(avl_is_empty(&dn->dn_dbufs)); 757 758 for (i = 0; i < TXG_SIZE; i++) { 759 ASSERT0(dn->dn_next_nblkptr[i]); 760 ASSERT0(dn->dn_next_nlevels[i]); 761 ASSERT0(dn->dn_next_indblkshift[i]); 762 ASSERT0(dn->dn_next_bonuslen[i]); 763 ASSERT0(dn->dn_next_bonustype[i]); 764 ASSERT0(dn->dn_rm_spillblk[i]); 765 ASSERT0(dn->dn_next_blksz[i]); 766 ASSERT0(dn->dn_next_maxblkid[i]); 767 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i])); 768 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 769 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 770 } 771 772 dn->dn_type = ot; 773 dnode_setdblksz(dn, blocksize); 774 dn->dn_indblkshift = ibs; 775 dn->dn_nlevels = 1; 776 dn->dn_num_slots = dn_slots; 777 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 778 dn->dn_nblkptr = 1; 779 else { 780 dn->dn_nblkptr = MIN(DN_MAX_NBLKPTR, 781 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 782 SPA_BLKPTRSHIFT)); 783 } 784 785 dn->dn_bonustype = bonustype; 786 dn->dn_bonuslen = bonuslen; 787 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 788 dn->dn_compress = ZIO_COMPRESS_INHERIT; 789 dn->dn_dirtyctx = 0; 790 791 dn->dn_free_txg = 0; 792 dn->dn_dirtyctx_firstset = NULL; 793 dn->dn_dirty_txg = 0; 794 795 dn->dn_allocated_txg = tx->tx_txg; 796 dn->dn_id_flags = 0; 797 798 dnode_setdirty(dn, tx); 799 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 800 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 801 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 802 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 803 } 804 805 void 806 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 807 dmu_object_type_t bonustype, int bonuslen, int dn_slots, 808 boolean_t keep_spill, dmu_tx_t *tx) 809 { 810 int nblkptr; 811 812 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 813 ASSERT3U(blocksize, <=, 814 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 815 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 816 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 817 ASSERT(tx->tx_txg != 0); 818 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 819 (bonustype != DMU_OT_NONE && bonuslen != 0) || 820 (bonustype == DMU_OT_SA && bonuslen == 0)); 821 ASSERT(DMU_OT_IS_VALID(bonustype)); 822 ASSERT3U(bonuslen, <=, 823 DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(dn->dn_objset)))); 824 ASSERT3U(bonuslen, <=, DN_BONUS_SIZE(dn_slots << DNODE_SHIFT)); 825 826 dnode_free_interior_slots(dn); 827 DNODE_STAT_BUMP(dnode_reallocate); 828 829 /* clean up any unreferenced dbufs */ 830 dnode_evict_dbufs(dn); 831 832 dn->dn_id_flags = 0; 833 834 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 835 dnode_setdirty(dn, tx); 836 if (dn->dn_datablksz != blocksize) { 837 /* change blocksize */ 838 ASSERT0(dn->dn_maxblkid); 839 ASSERT(BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 840 dnode_block_freed(dn, 0)); 841 842 dnode_setdblksz(dn, blocksize); 843 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = blocksize; 844 } 845 if (dn->dn_bonuslen != bonuslen) 846 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = bonuslen; 847 848 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 849 nblkptr = 1; 850 else 851 nblkptr = MIN(DN_MAX_NBLKPTR, 852 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 853 SPA_BLKPTRSHIFT)); 854 if (dn->dn_bonustype != bonustype) 855 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = bonustype; 856 if (dn->dn_nblkptr != nblkptr) 857 dn->dn_next_nblkptr[tx->tx_txg & TXG_MASK] = nblkptr; 858 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR && !keep_spill) { 859 dbuf_rm_spill(dn, tx); 860 dnode_rm_spill(dn, tx); 861 } 862 863 rw_exit(&dn->dn_struct_rwlock); 864 865 /* change type */ 866 dn->dn_type = ot; 867 868 /* change bonus size and type */ 869 mutex_enter(&dn->dn_mtx); 870 dn->dn_bonustype = bonustype; 871 dn->dn_bonuslen = bonuslen; 872 dn->dn_num_slots = dn_slots; 873 dn->dn_nblkptr = nblkptr; 874 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 875 dn->dn_compress = ZIO_COMPRESS_INHERIT; 876 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 877 878 /* fix up the bonus db_size */ 879 if (dn->dn_bonus) { 880 dn->dn_bonus->db.db_size = 881 DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) - 882 (dn->dn_nblkptr-1) * sizeof (blkptr_t); 883 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 884 } 885 886 dn->dn_allocated_txg = tx->tx_txg; 887 mutex_exit(&dn->dn_mtx); 888 } 889 890 #ifdef _KERNEL 891 static void 892 dnode_move_impl(dnode_t *odn, dnode_t *ndn) 893 { 894 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 895 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 896 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 897 898 /* Copy fields. */ 899 ndn->dn_objset = odn->dn_objset; 900 ndn->dn_object = odn->dn_object; 901 ndn->dn_dbuf = odn->dn_dbuf; 902 ndn->dn_handle = odn->dn_handle; 903 ndn->dn_phys = odn->dn_phys; 904 ndn->dn_type = odn->dn_type; 905 ndn->dn_bonuslen = odn->dn_bonuslen; 906 ndn->dn_bonustype = odn->dn_bonustype; 907 ndn->dn_nblkptr = odn->dn_nblkptr; 908 ndn->dn_checksum = odn->dn_checksum; 909 ndn->dn_compress = odn->dn_compress; 910 ndn->dn_nlevels = odn->dn_nlevels; 911 ndn->dn_indblkshift = odn->dn_indblkshift; 912 ndn->dn_datablkshift = odn->dn_datablkshift; 913 ndn->dn_datablkszsec = odn->dn_datablkszsec; 914 ndn->dn_datablksz = odn->dn_datablksz; 915 ndn->dn_maxblkid = odn->dn_maxblkid; 916 ndn->dn_num_slots = odn->dn_num_slots; 917 memcpy(ndn->dn_next_type, odn->dn_next_type, 918 sizeof (odn->dn_next_type)); 919 memcpy(ndn->dn_next_nblkptr, odn->dn_next_nblkptr, 920 sizeof (odn->dn_next_nblkptr)); 921 memcpy(ndn->dn_next_nlevels, odn->dn_next_nlevels, 922 sizeof (odn->dn_next_nlevels)); 923 memcpy(ndn->dn_next_indblkshift, odn->dn_next_indblkshift, 924 sizeof (odn->dn_next_indblkshift)); 925 memcpy(ndn->dn_next_bonustype, odn->dn_next_bonustype, 926 sizeof (odn->dn_next_bonustype)); 927 memcpy(ndn->dn_rm_spillblk, odn->dn_rm_spillblk, 928 sizeof (odn->dn_rm_spillblk)); 929 memcpy(ndn->dn_next_bonuslen, odn->dn_next_bonuslen, 930 sizeof (odn->dn_next_bonuslen)); 931 memcpy(ndn->dn_next_blksz, odn->dn_next_blksz, 932 sizeof (odn->dn_next_blksz)); 933 memcpy(ndn->dn_next_maxblkid, odn->dn_next_maxblkid, 934 sizeof (odn->dn_next_maxblkid)); 935 for (int i = 0; i < TXG_SIZE; i++) { 936 list_move_tail(&ndn->dn_dirty_records[i], 937 &odn->dn_dirty_records[i]); 938 } 939 memcpy(ndn->dn_free_ranges, odn->dn_free_ranges, 940 sizeof (odn->dn_free_ranges)); 941 ndn->dn_allocated_txg = odn->dn_allocated_txg; 942 ndn->dn_free_txg = odn->dn_free_txg; 943 ndn->dn_assigned_txg = odn->dn_assigned_txg; 944 ndn->dn_dirty_txg = odn->dn_dirty_txg; 945 ndn->dn_dirtyctx = odn->dn_dirtyctx; 946 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 947 ASSERT(zfs_refcount_count(&odn->dn_tx_holds) == 0); 948 zfs_refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 949 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 950 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 951 ndn->dn_dbufs_count = odn->dn_dbufs_count; 952 ndn->dn_bonus = odn->dn_bonus; 953 ndn->dn_have_spill = odn->dn_have_spill; 954 ndn->dn_zio = odn->dn_zio; 955 ndn->dn_oldused = odn->dn_oldused; 956 ndn->dn_oldflags = odn->dn_oldflags; 957 ndn->dn_olduid = odn->dn_olduid; 958 ndn->dn_oldgid = odn->dn_oldgid; 959 ndn->dn_oldprojid = odn->dn_oldprojid; 960 ndn->dn_newuid = odn->dn_newuid; 961 ndn->dn_newgid = odn->dn_newgid; 962 ndn->dn_newprojid = odn->dn_newprojid; 963 ndn->dn_id_flags = odn->dn_id_flags; 964 ndn->dn_storage_type = odn->dn_storage_type; 965 dmu_zfetch_init(&ndn->dn_zfetch, ndn); 966 967 /* 968 * Update back pointers. Updating the handle fixes the back pointer of 969 * every descendant dbuf as well as the bonus dbuf. 970 */ 971 ASSERT(ndn->dn_handle->dnh_dnode == odn); 972 ndn->dn_handle->dnh_dnode = ndn; 973 974 /* 975 * Invalidate the original dnode by clearing all of its back pointers. 976 */ 977 odn->dn_dbuf = NULL; 978 odn->dn_handle = NULL; 979 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 980 offsetof(dmu_buf_impl_t, db_link)); 981 odn->dn_dbufs_count = 0; 982 odn->dn_bonus = NULL; 983 dmu_zfetch_fini(&odn->dn_zfetch); 984 985 /* 986 * Set the low bit of the objset pointer to ensure that dnode_move() 987 * recognizes the dnode as invalid in any subsequent callback. 988 */ 989 POINTER_INVALIDATE(&odn->dn_objset); 990 991 /* 992 * Satisfy the destructor. 993 */ 994 for (int i = 0; i < TXG_SIZE; i++) { 995 list_create(&odn->dn_dirty_records[i], 996 sizeof (dbuf_dirty_record_t), 997 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 998 odn->dn_free_ranges[i] = NULL; 999 odn->dn_next_nlevels[i] = 0; 1000 odn->dn_next_indblkshift[i] = 0; 1001 odn->dn_next_bonustype[i] = 0; 1002 odn->dn_rm_spillblk[i] = 0; 1003 odn->dn_next_bonuslen[i] = 0; 1004 odn->dn_next_blksz[i] = 0; 1005 } 1006 odn->dn_allocated_txg = 0; 1007 odn->dn_free_txg = 0; 1008 odn->dn_assigned_txg = 0; 1009 odn->dn_dirty_txg = 0; 1010 odn->dn_dirtyctx = 0; 1011 odn->dn_dirtyctx_firstset = NULL; 1012 odn->dn_have_spill = B_FALSE; 1013 odn->dn_zio = NULL; 1014 odn->dn_oldused = 0; 1015 odn->dn_oldflags = 0; 1016 odn->dn_olduid = 0; 1017 odn->dn_oldgid = 0; 1018 odn->dn_oldprojid = ZFS_DEFAULT_PROJID; 1019 odn->dn_newuid = 0; 1020 odn->dn_newgid = 0; 1021 odn->dn_newprojid = ZFS_DEFAULT_PROJID; 1022 odn->dn_id_flags = 0; 1023 odn->dn_storage_type = DMU_OT_NONE; 1024 1025 /* 1026 * Mark the dnode. 1027 */ 1028 ndn->dn_moved = 1; 1029 odn->dn_moved = (uint8_t)-1; 1030 } 1031 1032 static kmem_cbrc_t 1033 dnode_move(void *buf, void *newbuf, size_t size, void *arg) 1034 { 1035 dnode_t *odn = buf, *ndn = newbuf; 1036 objset_t *os; 1037 int64_t refcount; 1038 uint32_t dbufs; 1039 1040 #ifndef USE_DNODE_HANDLE 1041 /* 1042 * We can't move dnodes if dbufs reference them directly without 1043 * using handles and respecitve locking. Unless USE_DNODE_HANDLE 1044 * is defined the code below is only to make sure it still builds, 1045 * but it should never be used, since it is unsafe. 1046 */ 1047 #ifdef ZFS_DEBUG 1048 PANIC("dnode_move() called without USE_DNODE_HANDLE"); 1049 #endif 1050 return (KMEM_CBRC_NO); 1051 #endif 1052 1053 /* 1054 * The dnode is on the objset's list of known dnodes if the objset 1055 * pointer is valid. We set the low bit of the objset pointer when 1056 * freeing the dnode to invalidate it, and the memory patterns written 1057 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 1058 * A newly created dnode sets the objset pointer last of all to indicate 1059 * that the dnode is known and in a valid state to be moved by this 1060 * function. 1061 */ 1062 os = odn->dn_objset; 1063 if (!POINTER_IS_VALID(os)) { 1064 DNODE_STAT_BUMP(dnode_move_invalid); 1065 return (KMEM_CBRC_DONT_KNOW); 1066 } 1067 1068 /* 1069 * Ensure that the objset does not go away during the move. 1070 */ 1071 rw_enter(&os_lock, RW_WRITER); 1072 if (os != odn->dn_objset) { 1073 rw_exit(&os_lock); 1074 DNODE_STAT_BUMP(dnode_move_recheck1); 1075 return (KMEM_CBRC_DONT_KNOW); 1076 } 1077 1078 /* 1079 * If the dnode is still valid, then so is the objset. We know that no 1080 * valid objset can be freed while we hold os_lock, so we can safely 1081 * ensure that the objset remains in use. 1082 */ 1083 mutex_enter(&os->os_lock); 1084 1085 /* 1086 * Recheck the objset pointer in case the dnode was removed just before 1087 * acquiring the lock. 1088 */ 1089 if (os != odn->dn_objset) { 1090 mutex_exit(&os->os_lock); 1091 rw_exit(&os_lock); 1092 DNODE_STAT_BUMP(dnode_move_recheck2); 1093 return (KMEM_CBRC_DONT_KNOW); 1094 } 1095 1096 /* 1097 * At this point we know that as long as we hold os->os_lock, the dnode 1098 * cannot be freed and fields within the dnode can be safely accessed. 1099 * The objset listing this dnode cannot go away as long as this dnode is 1100 * on its list. 1101 */ 1102 rw_exit(&os_lock); 1103 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 1104 mutex_exit(&os->os_lock); 1105 DNODE_STAT_BUMP(dnode_move_special); 1106 return (KMEM_CBRC_NO); 1107 } 1108 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 1109 1110 /* 1111 * Lock the dnode handle to prevent the dnode from obtaining any new 1112 * holds. This also prevents the descendant dbufs and the bonus dbuf 1113 * from accessing the dnode, so that we can discount their holds. The 1114 * handle is safe to access because we know that while the dnode cannot 1115 * go away, neither can its handle. Once we hold dnh_zrlock, we can 1116 * safely move any dnode referenced only by dbufs. 1117 */ 1118 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 1119 mutex_exit(&os->os_lock); 1120 DNODE_STAT_BUMP(dnode_move_handle); 1121 return (KMEM_CBRC_LATER); 1122 } 1123 1124 /* 1125 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 1126 * We need to guarantee that there is a hold for every dbuf in order to 1127 * determine whether the dnode is actively referenced. Falsely matching 1128 * a dbuf to an active hold would lead to an unsafe move. It's possible 1129 * that a thread already having an active dnode hold is about to add a 1130 * dbuf, and we can't compare hold and dbuf counts while the add is in 1131 * progress. 1132 */ 1133 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 1134 zrl_exit(&odn->dn_handle->dnh_zrlock); 1135 mutex_exit(&os->os_lock); 1136 DNODE_STAT_BUMP(dnode_move_rwlock); 1137 return (KMEM_CBRC_LATER); 1138 } 1139 1140 /* 1141 * A dbuf may be removed (evicted) without an active dnode hold. In that 1142 * case, the dbuf count is decremented under the handle lock before the 1143 * dbuf's hold is released. This order ensures that if we count the hold 1144 * after the dbuf is removed but before its hold is released, we will 1145 * treat the unmatched hold as active and exit safely. If we count the 1146 * hold before the dbuf is removed, the hold is discounted, and the 1147 * removal is blocked until the move completes. 1148 */ 1149 refcount = zfs_refcount_count(&odn->dn_holds); 1150 ASSERT(refcount >= 0); 1151 dbufs = DN_DBUFS_COUNT(odn); 1152 1153 /* We can't have more dbufs than dnode holds. */ 1154 ASSERT3U(dbufs, <=, refcount); 1155 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 1156 uint32_t, dbufs); 1157 1158 if (refcount > dbufs) { 1159 rw_exit(&odn->dn_struct_rwlock); 1160 zrl_exit(&odn->dn_handle->dnh_zrlock); 1161 mutex_exit(&os->os_lock); 1162 DNODE_STAT_BUMP(dnode_move_active); 1163 return (KMEM_CBRC_LATER); 1164 } 1165 1166 rw_exit(&odn->dn_struct_rwlock); 1167 1168 /* 1169 * At this point we know that anyone with a hold on the dnode is not 1170 * actively referencing it. The dnode is known and in a valid state to 1171 * move. We're holding the locks needed to execute the critical section. 1172 */ 1173 dnode_move_impl(odn, ndn); 1174 1175 list_link_replace(&odn->dn_link, &ndn->dn_link); 1176 /* If the dnode was safe to move, the refcount cannot have changed. */ 1177 ASSERT(refcount == zfs_refcount_count(&ndn->dn_holds)); 1178 ASSERT(dbufs == DN_DBUFS_COUNT(ndn)); 1179 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 1180 mutex_exit(&os->os_lock); 1181 1182 return (KMEM_CBRC_YES); 1183 } 1184 #endif /* _KERNEL */ 1185 1186 static void 1187 dnode_slots_hold(dnode_children_t *children, int idx, int slots) 1188 { 1189 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1190 1191 for (int i = idx; i < idx + slots; i++) { 1192 dnode_handle_t *dnh = &children->dnc_children[i]; 1193 zrl_add(&dnh->dnh_zrlock); 1194 } 1195 } 1196 1197 static void 1198 dnode_slots_rele(dnode_children_t *children, int idx, int slots) 1199 { 1200 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1201 1202 for (int i = idx; i < idx + slots; i++) { 1203 dnode_handle_t *dnh = &children->dnc_children[i]; 1204 1205 if (zrl_is_locked(&dnh->dnh_zrlock)) 1206 zrl_exit(&dnh->dnh_zrlock); 1207 else 1208 zrl_remove(&dnh->dnh_zrlock); 1209 } 1210 } 1211 1212 static int 1213 dnode_slots_tryenter(dnode_children_t *children, int idx, int slots) 1214 { 1215 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1216 1217 for (int i = idx; i < idx + slots; i++) { 1218 dnode_handle_t *dnh = &children->dnc_children[i]; 1219 1220 if (!zrl_tryenter(&dnh->dnh_zrlock)) { 1221 for (int j = idx; j < i; j++) { 1222 dnh = &children->dnc_children[j]; 1223 zrl_exit(&dnh->dnh_zrlock); 1224 } 1225 1226 return (0); 1227 } 1228 } 1229 1230 return (1); 1231 } 1232 1233 static void 1234 dnode_set_slots(dnode_children_t *children, int idx, int slots, void *ptr) 1235 { 1236 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1237 1238 for (int i = idx; i < idx + slots; i++) { 1239 dnode_handle_t *dnh = &children->dnc_children[i]; 1240 dnh->dnh_dnode = ptr; 1241 } 1242 } 1243 1244 static boolean_t 1245 dnode_check_slots_free(dnode_children_t *children, int idx, int slots) 1246 { 1247 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1248 1249 /* 1250 * If all dnode slots are either already free or 1251 * evictable return B_TRUE. 1252 */ 1253 for (int i = idx; i < idx + slots; i++) { 1254 dnode_handle_t *dnh = &children->dnc_children[i]; 1255 dnode_t *dn = dnh->dnh_dnode; 1256 1257 if (dn == DN_SLOT_FREE) { 1258 continue; 1259 } else if (DN_SLOT_IS_PTR(dn)) { 1260 mutex_enter(&dn->dn_mtx); 1261 boolean_t can_free = (dn->dn_type == DMU_OT_NONE && 1262 zfs_refcount_is_zero(&dn->dn_holds) && 1263 !DNODE_IS_DIRTY(dn)); 1264 mutex_exit(&dn->dn_mtx); 1265 1266 if (!can_free) 1267 return (B_FALSE); 1268 else 1269 continue; 1270 } else { 1271 return (B_FALSE); 1272 } 1273 } 1274 1275 return (B_TRUE); 1276 } 1277 1278 static uint_t 1279 dnode_reclaim_slots(dnode_children_t *children, int idx, int slots) 1280 { 1281 uint_t reclaimed = 0; 1282 1283 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1284 1285 for (int i = idx; i < idx + slots; i++) { 1286 dnode_handle_t *dnh = &children->dnc_children[i]; 1287 1288 ASSERT(zrl_is_locked(&dnh->dnh_zrlock)); 1289 1290 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1291 ASSERT3S(dnh->dnh_dnode->dn_type, ==, DMU_OT_NONE); 1292 dnode_destroy(dnh->dnh_dnode); 1293 dnh->dnh_dnode = DN_SLOT_FREE; 1294 reclaimed++; 1295 } 1296 } 1297 1298 return (reclaimed); 1299 } 1300 1301 void 1302 dnode_free_interior_slots(dnode_t *dn) 1303 { 1304 dnode_children_t *children = dmu_buf_get_user(&dn->dn_dbuf->db); 1305 int epb = dn->dn_dbuf->db.db_size >> DNODE_SHIFT; 1306 int idx = (dn->dn_object & (epb - 1)) + 1; 1307 int slots = dn->dn_num_slots - 1; 1308 1309 if (slots == 0) 1310 return; 1311 1312 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1313 1314 while (!dnode_slots_tryenter(children, idx, slots)) { 1315 DNODE_STAT_BUMP(dnode_free_interior_lock_retry); 1316 kpreempt(KPREEMPT_SYNC); 1317 } 1318 1319 dnode_set_slots(children, idx, slots, DN_SLOT_FREE); 1320 dnode_slots_rele(children, idx, slots); 1321 } 1322 1323 void 1324 dnode_special_close(dnode_handle_t *dnh) 1325 { 1326 dnode_t *dn = dnh->dnh_dnode; 1327 1328 /* 1329 * Ensure dnode_rele_and_unlock() has released dn_mtx, after final 1330 * zfs_refcount_remove() 1331 */ 1332 mutex_enter(&dn->dn_mtx); 1333 if (zfs_refcount_count(&dn->dn_holds) > 0) 1334 cv_wait(&dn->dn_nodnholds, &dn->dn_mtx); 1335 mutex_exit(&dn->dn_mtx); 1336 ASSERT3U(zfs_refcount_count(&dn->dn_holds), ==, 0); 1337 1338 ASSERT(dn->dn_dbuf == NULL || 1339 dmu_buf_get_user(&dn->dn_dbuf->db) == NULL); 1340 zrl_add(&dnh->dnh_zrlock); 1341 dnode_destroy(dn); /* implicit zrl_remove() */ 1342 zrl_destroy(&dnh->dnh_zrlock); 1343 dnh->dnh_dnode = NULL; 1344 } 1345 1346 void 1347 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 1348 dnode_handle_t *dnh) 1349 { 1350 dnode_t *dn; 1351 1352 zrl_init(&dnh->dnh_zrlock); 1353 VERIFY3U(1, ==, zrl_tryenter(&dnh->dnh_zrlock)); 1354 1355 dn = dnode_create(os, dnp, NULL, object, dnh); 1356 DNODE_VERIFY(dn); 1357 1358 zrl_exit(&dnh->dnh_zrlock); 1359 } 1360 1361 static void 1362 dnode_buf_evict_async(void *dbu) 1363 { 1364 dnode_children_t *dnc = dbu; 1365 1366 DNODE_STAT_BUMP(dnode_buf_evict); 1367 1368 for (int i = 0; i < dnc->dnc_count; i++) { 1369 dnode_handle_t *dnh = &dnc->dnc_children[i]; 1370 dnode_t *dn; 1371 1372 /* 1373 * The dnode handle lock guards against the dnode moving to 1374 * another valid address, so there is no need here to guard 1375 * against changes to or from NULL. 1376 */ 1377 if (!DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1378 zrl_destroy(&dnh->dnh_zrlock); 1379 dnh->dnh_dnode = DN_SLOT_UNINIT; 1380 continue; 1381 } 1382 1383 zrl_add(&dnh->dnh_zrlock); 1384 dn = dnh->dnh_dnode; 1385 /* 1386 * If there are holds on this dnode, then there should 1387 * be holds on the dnode's containing dbuf as well; thus 1388 * it wouldn't be eligible for eviction and this function 1389 * would not have been called. 1390 */ 1391 ASSERT(zfs_refcount_is_zero(&dn->dn_holds)); 1392 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 1393 1394 dnode_destroy(dn); /* implicit zrl_remove() for first slot */ 1395 zrl_destroy(&dnh->dnh_zrlock); 1396 dnh->dnh_dnode = DN_SLOT_UNINIT; 1397 } 1398 kmem_free(dnc, sizeof (dnode_children_t) + 1399 dnc->dnc_count * sizeof (dnode_handle_t)); 1400 } 1401 1402 /* 1403 * When the DNODE_MUST_BE_FREE flag is set, the "slots" parameter is used 1404 * to ensure the hole at the specified object offset is large enough to 1405 * hold the dnode being created. The slots parameter is also used to ensure 1406 * a dnode does not span multiple dnode blocks. In both of these cases, if 1407 * a failure occurs, ENOSPC is returned. Keep in mind, these failure cases 1408 * are only possible when using DNODE_MUST_BE_FREE. 1409 * 1410 * If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0. 1411 * dnode_hold_impl() will check if the requested dnode is already consumed 1412 * as an extra dnode slot by an large dnode, in which case it returns 1413 * ENOENT. 1414 * 1415 * If the DNODE_DRY_RUN flag is set, we don't actually hold the dnode, just 1416 * return whether the hold would succeed or not. tag and dnp should set to 1417 * NULL in this case. 1418 * 1419 * errors: 1420 * EINVAL - Invalid object number or flags. 1421 * ENOSPC - Hole too small to fulfill "slots" request (DNODE_MUST_BE_FREE) 1422 * EEXIST - Refers to an allocated dnode (DNODE_MUST_BE_FREE) 1423 * - Refers to a freeing dnode (DNODE_MUST_BE_FREE) 1424 * - Refers to an interior dnode slot (DNODE_MUST_BE_ALLOCATED) 1425 * ENOENT - The requested dnode is not allocated (DNODE_MUST_BE_ALLOCATED) 1426 * - The requested dnode is being freed (DNODE_MUST_BE_ALLOCATED) 1427 * EIO - I/O error when reading the meta dnode dbuf. 1428 * 1429 * succeeds even for free dnodes. 1430 */ 1431 int 1432 dnode_hold_impl(objset_t *os, uint64_t object, int flag, int slots, 1433 const void *tag, dnode_t **dnp) 1434 { 1435 int epb, idx, err; 1436 int drop_struct_lock = FALSE; 1437 int type; 1438 uint64_t blk; 1439 dnode_t *mdn, *dn; 1440 dmu_buf_impl_t *db; 1441 dnode_children_t *dnc; 1442 dnode_phys_t *dn_block; 1443 dnode_handle_t *dnh; 1444 1445 ASSERT(!(flag & DNODE_MUST_BE_ALLOCATED) || (slots == 0)); 1446 ASSERT(!(flag & DNODE_MUST_BE_FREE) || (slots > 0)); 1447 IMPLY(flag & DNODE_DRY_RUN, (tag == NULL) && (dnp == NULL)); 1448 1449 /* 1450 * If you are holding the spa config lock as writer, you shouldn't 1451 * be asking the DMU to do *anything* unless it's the root pool 1452 * which may require us to read from the root filesystem while 1453 * holding some (not all) of the locks as writer. 1454 */ 1455 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1456 (spa_is_root(os->os_spa) && 1457 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1458 1459 ASSERT((flag & DNODE_MUST_BE_ALLOCATED) || (flag & DNODE_MUST_BE_FREE)); 1460 1461 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT || 1462 object == DMU_PROJECTUSED_OBJECT) { 1463 if (object == DMU_USERUSED_OBJECT) 1464 dn = DMU_USERUSED_DNODE(os); 1465 else if (object == DMU_GROUPUSED_OBJECT) 1466 dn = DMU_GROUPUSED_DNODE(os); 1467 else 1468 dn = DMU_PROJECTUSED_DNODE(os); 1469 if (dn == NULL) 1470 return (SET_ERROR(ENOENT)); 1471 type = dn->dn_type; 1472 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1473 return (SET_ERROR(ENOENT)); 1474 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1475 return (SET_ERROR(EEXIST)); 1476 DNODE_VERIFY(dn); 1477 /* Don't actually hold if dry run, just return 0 */ 1478 if (!(flag & DNODE_DRY_RUN)) { 1479 (void) zfs_refcount_add(&dn->dn_holds, tag); 1480 *dnp = dn; 1481 } 1482 return (0); 1483 } 1484 1485 if (object == 0 || object >= DN_MAX_OBJECT) 1486 return (SET_ERROR(EINVAL)); 1487 1488 mdn = DMU_META_DNODE(os); 1489 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1490 1491 DNODE_VERIFY(mdn); 1492 1493 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1494 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1495 drop_struct_lock = TRUE; 1496 } 1497 1498 blk = dbuf_whichblock(mdn, 0, object * sizeof (dnode_phys_t)); 1499 db = dbuf_hold(mdn, blk, FTAG); 1500 if (drop_struct_lock) 1501 rw_exit(&mdn->dn_struct_rwlock); 1502 if (db == NULL) { 1503 DNODE_STAT_BUMP(dnode_hold_dbuf_hold); 1504 return (SET_ERROR(EIO)); 1505 } 1506 1507 /* 1508 * We do not need to decrypt to read the dnode so it doesn't matter 1509 * if we get the encrypted or decrypted version. 1510 */ 1511 err = dbuf_read(db, NULL, DB_RF_CANFAIL | 1512 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH); 1513 if (err) { 1514 DNODE_STAT_BUMP(dnode_hold_dbuf_read); 1515 dbuf_rele(db, FTAG); 1516 return (err); 1517 } 1518 1519 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1520 epb = db->db.db_size >> DNODE_SHIFT; 1521 1522 idx = object & (epb - 1); 1523 dn_block = (dnode_phys_t *)db->db.db_data; 1524 1525 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1526 dnc = dmu_buf_get_user(&db->db); 1527 dnh = NULL; 1528 if (dnc == NULL) { 1529 dnode_children_t *winner; 1530 int skip = 0; 1531 1532 dnc = kmem_zalloc(sizeof (dnode_children_t) + 1533 epb * sizeof (dnode_handle_t), KM_SLEEP); 1534 dnc->dnc_count = epb; 1535 dnh = &dnc->dnc_children[0]; 1536 1537 /* Initialize dnode slot status from dnode_phys_t */ 1538 for (int i = 0; i < epb; i++) { 1539 zrl_init(&dnh[i].dnh_zrlock); 1540 1541 if (skip) { 1542 skip--; 1543 continue; 1544 } 1545 1546 if (dn_block[i].dn_type != DMU_OT_NONE) { 1547 int interior = dn_block[i].dn_extra_slots; 1548 1549 dnode_set_slots(dnc, i, 1, DN_SLOT_ALLOCATED); 1550 dnode_set_slots(dnc, i + 1, interior, 1551 DN_SLOT_INTERIOR); 1552 skip = interior; 1553 } else { 1554 dnh[i].dnh_dnode = DN_SLOT_FREE; 1555 skip = 0; 1556 } 1557 } 1558 1559 dmu_buf_init_user(&dnc->dnc_dbu, NULL, 1560 dnode_buf_evict_async, NULL); 1561 winner = dmu_buf_set_user(&db->db, &dnc->dnc_dbu); 1562 if (winner != NULL) { 1563 1564 for (int i = 0; i < epb; i++) 1565 zrl_destroy(&dnh[i].dnh_zrlock); 1566 1567 kmem_free(dnc, sizeof (dnode_children_t) + 1568 epb * sizeof (dnode_handle_t)); 1569 dnc = winner; 1570 } 1571 } 1572 1573 ASSERT(dnc->dnc_count == epb); 1574 1575 if (flag & DNODE_MUST_BE_ALLOCATED) { 1576 slots = 1; 1577 1578 dnode_slots_hold(dnc, idx, slots); 1579 dnh = &dnc->dnc_children[idx]; 1580 1581 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1582 dn = dnh->dnh_dnode; 1583 } else if (dnh->dnh_dnode == DN_SLOT_INTERIOR) { 1584 DNODE_STAT_BUMP(dnode_hold_alloc_interior); 1585 dnode_slots_rele(dnc, idx, slots); 1586 dbuf_rele(db, FTAG); 1587 return (SET_ERROR(EEXIST)); 1588 } else if (dnh->dnh_dnode != DN_SLOT_ALLOCATED) { 1589 DNODE_STAT_BUMP(dnode_hold_alloc_misses); 1590 dnode_slots_rele(dnc, idx, slots); 1591 dbuf_rele(db, FTAG); 1592 return (SET_ERROR(ENOENT)); 1593 } else { 1594 dnode_slots_rele(dnc, idx, slots); 1595 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1596 DNODE_STAT_BUMP(dnode_hold_alloc_lock_retry); 1597 kpreempt(KPREEMPT_SYNC); 1598 } 1599 1600 /* 1601 * Someone else won the race and called dnode_create() 1602 * after we checked DN_SLOT_IS_PTR() above but before 1603 * we acquired the lock. 1604 */ 1605 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1606 DNODE_STAT_BUMP(dnode_hold_alloc_lock_misses); 1607 dn = dnh->dnh_dnode; 1608 } else { 1609 dn = dnode_create(os, dn_block + idx, db, 1610 object, dnh); 1611 dmu_buf_add_user_size(&db->db, 1612 sizeof (dnode_t)); 1613 } 1614 } 1615 1616 mutex_enter(&dn->dn_mtx); 1617 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg != 0) { 1618 DNODE_STAT_BUMP(dnode_hold_alloc_type_none); 1619 mutex_exit(&dn->dn_mtx); 1620 dnode_slots_rele(dnc, idx, slots); 1621 dbuf_rele(db, FTAG); 1622 return (SET_ERROR(ENOENT)); 1623 } 1624 1625 /* Don't actually hold if dry run, just return 0 */ 1626 if (flag & DNODE_DRY_RUN) { 1627 mutex_exit(&dn->dn_mtx); 1628 dnode_slots_rele(dnc, idx, slots); 1629 dbuf_rele(db, FTAG); 1630 return (0); 1631 } 1632 1633 DNODE_STAT_BUMP(dnode_hold_alloc_hits); 1634 } else if (flag & DNODE_MUST_BE_FREE) { 1635 1636 if (idx + slots - 1 >= DNODES_PER_BLOCK) { 1637 DNODE_STAT_BUMP(dnode_hold_free_overflow); 1638 dbuf_rele(db, FTAG); 1639 return (SET_ERROR(ENOSPC)); 1640 } 1641 1642 dnode_slots_hold(dnc, idx, slots); 1643 1644 if (!dnode_check_slots_free(dnc, idx, slots)) { 1645 DNODE_STAT_BUMP(dnode_hold_free_misses); 1646 dnode_slots_rele(dnc, idx, slots); 1647 dbuf_rele(db, FTAG); 1648 return (SET_ERROR(ENOSPC)); 1649 } 1650 1651 dnode_slots_rele(dnc, idx, slots); 1652 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1653 DNODE_STAT_BUMP(dnode_hold_free_lock_retry); 1654 kpreempt(KPREEMPT_SYNC); 1655 } 1656 1657 if (!dnode_check_slots_free(dnc, idx, slots)) { 1658 DNODE_STAT_BUMP(dnode_hold_free_lock_misses); 1659 dnode_slots_rele(dnc, idx, slots); 1660 dbuf_rele(db, FTAG); 1661 return (SET_ERROR(ENOSPC)); 1662 } 1663 1664 /* 1665 * Allocated but otherwise free dnodes which would 1666 * be in the interior of a multi-slot dnodes need 1667 * to be freed. Single slot dnodes can be safely 1668 * re-purposed as a performance optimization. 1669 */ 1670 if (slots > 1) { 1671 uint_t reclaimed = 1672 dnode_reclaim_slots(dnc, idx + 1, slots - 1); 1673 if (reclaimed > 0) 1674 dmu_buf_sub_user_size(&db->db, 1675 reclaimed * sizeof (dnode_t)); 1676 } 1677 1678 dnh = &dnc->dnc_children[idx]; 1679 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1680 dn = dnh->dnh_dnode; 1681 } else { 1682 dn = dnode_create(os, dn_block + idx, db, 1683 object, dnh); 1684 dmu_buf_add_user_size(&db->db, sizeof (dnode_t)); 1685 } 1686 1687 mutex_enter(&dn->dn_mtx); 1688 if (!zfs_refcount_is_zero(&dn->dn_holds) || dn->dn_free_txg) { 1689 DNODE_STAT_BUMP(dnode_hold_free_refcount); 1690 mutex_exit(&dn->dn_mtx); 1691 dnode_slots_rele(dnc, idx, slots); 1692 dbuf_rele(db, FTAG); 1693 return (SET_ERROR(EEXIST)); 1694 } 1695 1696 /* Don't actually hold if dry run, just return 0 */ 1697 if (flag & DNODE_DRY_RUN) { 1698 mutex_exit(&dn->dn_mtx); 1699 dnode_slots_rele(dnc, idx, slots); 1700 dbuf_rele(db, FTAG); 1701 return (0); 1702 } 1703 1704 dnode_set_slots(dnc, idx + 1, slots - 1, DN_SLOT_INTERIOR); 1705 DNODE_STAT_BUMP(dnode_hold_free_hits); 1706 } else { 1707 dbuf_rele(db, FTAG); 1708 return (SET_ERROR(EINVAL)); 1709 } 1710 1711 ASSERT0(dn->dn_free_txg); 1712 1713 if (zfs_refcount_add(&dn->dn_holds, tag) == 1) 1714 dbuf_add_ref(db, dnh); 1715 1716 mutex_exit(&dn->dn_mtx); 1717 1718 /* Now we can rely on the hold to prevent the dnode from moving. */ 1719 dnode_slots_rele(dnc, idx, slots); 1720 1721 DNODE_VERIFY(dn); 1722 ASSERT3P(dnp, !=, NULL); 1723 ASSERT3P(dn->dn_dbuf, ==, db); 1724 ASSERT3U(dn->dn_object, ==, object); 1725 dbuf_rele(db, FTAG); 1726 1727 *dnp = dn; 1728 return (0); 1729 } 1730 1731 /* 1732 * Return held dnode if the object is allocated, NULL if not. 1733 */ 1734 int 1735 dnode_hold(objset_t *os, uint64_t object, const void *tag, dnode_t **dnp) 1736 { 1737 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 0, tag, 1738 dnp)); 1739 } 1740 1741 /* 1742 * Can only add a reference if there is already at least one 1743 * reference on the dnode. Returns FALSE if unable to add a 1744 * new reference. 1745 */ 1746 boolean_t 1747 dnode_add_ref(dnode_t *dn, const void *tag) 1748 { 1749 mutex_enter(&dn->dn_mtx); 1750 if (zfs_refcount_is_zero(&dn->dn_holds)) { 1751 mutex_exit(&dn->dn_mtx); 1752 return (FALSE); 1753 } 1754 VERIFY(1 < zfs_refcount_add(&dn->dn_holds, tag)); 1755 mutex_exit(&dn->dn_mtx); 1756 return (TRUE); 1757 } 1758 1759 void 1760 dnode_rele(dnode_t *dn, const void *tag) 1761 { 1762 mutex_enter(&dn->dn_mtx); 1763 dnode_rele_and_unlock(dn, tag, B_FALSE); 1764 } 1765 1766 void 1767 dnode_rele_and_unlock(dnode_t *dn, const void *tag, boolean_t evicting) 1768 { 1769 uint64_t refs; 1770 /* Get while the hold prevents the dnode from moving. */ 1771 dmu_buf_impl_t *db = dn->dn_dbuf; 1772 dnode_handle_t *dnh = dn->dn_handle; 1773 1774 refs = zfs_refcount_remove(&dn->dn_holds, tag); 1775 if (refs == 0) 1776 cv_broadcast(&dn->dn_nodnholds); 1777 mutex_exit(&dn->dn_mtx); 1778 /* dnode could get destroyed at this point, so don't use it anymore */ 1779 1780 /* 1781 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1782 * indirectly by dbuf_rele() while relying on the dnode handle to 1783 * prevent the dnode from moving, since releasing the last hold could 1784 * result in the dnode's parent dbuf evicting its dnode handles. For 1785 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1786 * other direct or indirect hold on the dnode must first drop the dnode 1787 * handle. 1788 */ 1789 #ifdef ZFS_DEBUG 1790 ASSERT(refs > 0 || zrl_owner(&dnh->dnh_zrlock) != curthread); 1791 #endif 1792 1793 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1794 if (refs == 0 && db != NULL) { 1795 /* 1796 * Another thread could add a hold to the dnode handle in 1797 * dnode_hold_impl() while holding the parent dbuf. Since the 1798 * hold on the parent dbuf prevents the handle from being 1799 * destroyed, the hold on the handle is OK. We can't yet assert 1800 * that the handle has zero references, but that will be 1801 * asserted anyway when the handle gets destroyed. 1802 */ 1803 mutex_enter(&db->db_mtx); 1804 dbuf_rele_and_unlock(db, dnh, evicting); 1805 } 1806 } 1807 1808 /* 1809 * Test whether we can create a dnode at the specified location. 1810 */ 1811 int 1812 dnode_try_claim(objset_t *os, uint64_t object, int slots) 1813 { 1814 return (dnode_hold_impl(os, object, DNODE_MUST_BE_FREE | DNODE_DRY_RUN, 1815 slots, NULL, NULL)); 1816 } 1817 1818 /* 1819 * Checks if the dnode itself is dirty, or is carrying any uncommitted records. 1820 * It is important to check both conditions, as some operations (eg appending 1821 * to a file) can dirty both as a single logical unit, but they are not synced 1822 * out atomically, so checking one and not the other can result in an object 1823 * appearing to be clean mid-way through a commit. 1824 * 1825 * Do not change this lightly! If you get it wrong, dmu_offset_next() can 1826 * detect a hole where there is really data, leading to silent corruption. 1827 */ 1828 boolean_t 1829 dnode_is_dirty(dnode_t *dn) 1830 { 1831 mutex_enter(&dn->dn_mtx); 1832 1833 for (int i = 0; i < TXG_SIZE; i++) { 1834 if (multilist_link_active(&dn->dn_dirty_link[i]) || 1835 !list_is_empty(&dn->dn_dirty_records[i])) { 1836 mutex_exit(&dn->dn_mtx); 1837 return (B_TRUE); 1838 } 1839 } 1840 1841 mutex_exit(&dn->dn_mtx); 1842 1843 return (B_FALSE); 1844 } 1845 1846 void 1847 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1848 { 1849 objset_t *os = dn->dn_objset; 1850 uint64_t txg = tx->tx_txg; 1851 1852 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1853 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1854 return; 1855 } 1856 1857 DNODE_VERIFY(dn); 1858 1859 #ifdef ZFS_DEBUG 1860 mutex_enter(&dn->dn_mtx); 1861 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1862 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1863 mutex_exit(&dn->dn_mtx); 1864 #endif 1865 1866 /* 1867 * Determine old uid/gid when necessary 1868 */ 1869 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1870 1871 multilist_t *dirtylist = &os->os_dirty_dnodes[txg & TXG_MASK]; 1872 multilist_sublist_t *mls = multilist_sublist_lock_obj(dirtylist, dn); 1873 1874 /* 1875 * If we are already marked dirty, we're done. 1876 */ 1877 if (multilist_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1878 multilist_sublist_unlock(mls); 1879 return; 1880 } 1881 1882 ASSERT(!zfs_refcount_is_zero(&dn->dn_holds) || 1883 !avl_is_empty(&dn->dn_dbufs)); 1884 ASSERT(dn->dn_datablksz != 0); 1885 ASSERT0(dn->dn_next_bonuslen[txg & TXG_MASK]); 1886 ASSERT0(dn->dn_next_blksz[txg & TXG_MASK]); 1887 ASSERT0(dn->dn_next_bonustype[txg & TXG_MASK]); 1888 1889 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1890 (u_longlong_t)dn->dn_object, (u_longlong_t)txg); 1891 1892 multilist_sublist_insert_head(mls, dn); 1893 1894 multilist_sublist_unlock(mls); 1895 1896 /* 1897 * The dnode maintains a hold on its containing dbuf as 1898 * long as there are holds on it. Each instantiated child 1899 * dbuf maintains a hold on the dnode. When the last child 1900 * drops its hold, the dnode will drop its hold on the 1901 * containing dbuf. We add a "dirty hold" here so that the 1902 * dnode will hang around after we finish processing its 1903 * children. 1904 */ 1905 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1906 1907 (void) dbuf_dirty(dn->dn_dbuf, tx); 1908 1909 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1910 } 1911 1912 void 1913 dnode_free(dnode_t *dn, dmu_tx_t *tx) 1914 { 1915 mutex_enter(&dn->dn_mtx); 1916 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1917 mutex_exit(&dn->dn_mtx); 1918 return; 1919 } 1920 dn->dn_free_txg = tx->tx_txg; 1921 mutex_exit(&dn->dn_mtx); 1922 1923 dnode_setdirty(dn, tx); 1924 } 1925 1926 /* 1927 * Try to change the block size for the indicated dnode. This can only 1928 * succeed if there are no blocks allocated or dirty beyond first block 1929 */ 1930 int 1931 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1932 { 1933 dmu_buf_impl_t *db; 1934 int err; 1935 1936 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 1937 if (size == 0) 1938 size = SPA_MINBLOCKSIZE; 1939 else 1940 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1941 1942 if (ibs == dn->dn_indblkshift) 1943 ibs = 0; 1944 1945 if (size == dn->dn_datablksz && ibs == 0) 1946 return (0); 1947 1948 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1949 1950 /* Check for any allocated blocks beyond the first */ 1951 if (dn->dn_maxblkid != 0) 1952 goto fail; 1953 1954 mutex_enter(&dn->dn_dbufs_mtx); 1955 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1956 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1957 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1958 db->db_blkid != DMU_SPILL_BLKID) { 1959 mutex_exit(&dn->dn_dbufs_mtx); 1960 goto fail; 1961 } 1962 } 1963 mutex_exit(&dn->dn_dbufs_mtx); 1964 1965 if (ibs && dn->dn_nlevels != 1) 1966 goto fail; 1967 1968 dnode_setdirty(dn, tx); 1969 if (size != dn->dn_datablksz) { 1970 /* resize the old block */ 1971 err = dbuf_hold_impl(dn, 0, 0, TRUE, FALSE, FTAG, &db); 1972 if (err == 0) { 1973 dbuf_new_size(db, size, tx); 1974 } else if (err != ENOENT) { 1975 goto fail; 1976 } 1977 1978 dnode_setdblksz(dn, size); 1979 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = size; 1980 if (db) 1981 dbuf_rele(db, FTAG); 1982 } 1983 if (ibs) { 1984 dn->dn_indblkshift = ibs; 1985 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 1986 } 1987 1988 rw_exit(&dn->dn_struct_rwlock); 1989 return (0); 1990 1991 fail: 1992 rw_exit(&dn->dn_struct_rwlock); 1993 return (SET_ERROR(ENOTSUP)); 1994 } 1995 1996 static void 1997 dnode_set_nlevels_impl(dnode_t *dn, int new_nlevels, dmu_tx_t *tx) 1998 { 1999 uint64_t txgoff = tx->tx_txg & TXG_MASK; 2000 int old_nlevels = dn->dn_nlevels; 2001 dmu_buf_impl_t *db; 2002 list_t *list; 2003 dbuf_dirty_record_t *new, *dr, *dr_next; 2004 2005 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 2006 2007 ASSERT3U(new_nlevels, >, dn->dn_nlevels); 2008 dn->dn_nlevels = new_nlevels; 2009 2010 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 2011 dn->dn_next_nlevels[txgoff] = new_nlevels; 2012 2013 /* dirty the left indirects */ 2014 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 2015 ASSERT(db != NULL); 2016 new = dbuf_dirty(db, tx); 2017 dbuf_rele(db, FTAG); 2018 2019 /* transfer the dirty records to the new indirect */ 2020 mutex_enter(&dn->dn_mtx); 2021 mutex_enter(&new->dt.di.dr_mtx); 2022 list = &dn->dn_dirty_records[txgoff]; 2023 for (dr = list_head(list); dr; dr = dr_next) { 2024 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 2025 2026 IMPLY(dr->dr_dbuf == NULL, old_nlevels == 1); 2027 if (dr->dr_dbuf == NULL || 2028 (dr->dr_dbuf->db_level == old_nlevels - 1 && 2029 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 2030 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID)) { 2031 list_remove(&dn->dn_dirty_records[txgoff], dr); 2032 list_insert_tail(&new->dt.di.dr_children, dr); 2033 dr->dr_parent = new; 2034 } 2035 } 2036 mutex_exit(&new->dt.di.dr_mtx); 2037 mutex_exit(&dn->dn_mtx); 2038 } 2039 2040 int 2041 dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx) 2042 { 2043 int ret = 0; 2044 2045 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2046 2047 if (dn->dn_nlevels == nlevels) { 2048 ret = 0; 2049 goto out; 2050 } else if (nlevels < dn->dn_nlevels) { 2051 ret = SET_ERROR(EINVAL); 2052 goto out; 2053 } 2054 2055 dnode_set_nlevels_impl(dn, nlevels, tx); 2056 2057 out: 2058 rw_exit(&dn->dn_struct_rwlock); 2059 return (ret); 2060 } 2061 2062 /* read-holding callers must not rely on the lock being continuously held */ 2063 void 2064 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read, 2065 boolean_t force) 2066 { 2067 int epbs, new_nlevels; 2068 uint64_t sz; 2069 2070 ASSERT(blkid != DMU_BONUS_BLKID); 2071 2072 ASSERT(have_read ? 2073 RW_READ_HELD(&dn->dn_struct_rwlock) : 2074 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 2075 2076 /* 2077 * if we have a read-lock, check to see if we need to do any work 2078 * before upgrading to a write-lock. 2079 */ 2080 if (have_read) { 2081 if (blkid <= dn->dn_maxblkid) 2082 return; 2083 2084 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 2085 rw_exit(&dn->dn_struct_rwlock); 2086 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2087 } 2088 } 2089 2090 /* 2091 * Raw sends (indicated by the force flag) require that we take the 2092 * given blkid even if the value is lower than the current value. 2093 */ 2094 if (!force && blkid <= dn->dn_maxblkid) 2095 goto out; 2096 2097 /* 2098 * We use the (otherwise unused) top bit of dn_next_maxblkid[txgoff] 2099 * to indicate that this field is set. This allows us to set the 2100 * maxblkid to 0 on an existing object in dnode_sync(). 2101 */ 2102 dn->dn_maxblkid = blkid; 2103 dn->dn_next_maxblkid[tx->tx_txg & TXG_MASK] = 2104 blkid | DMU_NEXT_MAXBLKID_SET; 2105 2106 /* 2107 * Compute the number of levels necessary to support the new maxblkid. 2108 * Raw sends will ensure nlevels is set correctly for us. 2109 */ 2110 new_nlevels = 1; 2111 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2112 for (sz = dn->dn_nblkptr; 2113 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 2114 new_nlevels++; 2115 2116 ASSERT3U(new_nlevels, <=, DN_MAX_LEVELS); 2117 2118 if (!force) { 2119 if (new_nlevels > dn->dn_nlevels) 2120 dnode_set_nlevels_impl(dn, new_nlevels, tx); 2121 } else { 2122 ASSERT3U(dn->dn_nlevels, >=, new_nlevels); 2123 } 2124 2125 out: 2126 if (have_read) 2127 rw_downgrade(&dn->dn_struct_rwlock); 2128 } 2129 2130 static void 2131 dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx) 2132 { 2133 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG); 2134 if (db != NULL) { 2135 dmu_buf_will_dirty(&db->db, tx); 2136 dbuf_rele(db, FTAG); 2137 } 2138 } 2139 2140 /* 2141 * Dirty all the in-core level-1 dbufs in the range specified by start_blkid 2142 * and end_blkid. 2143 */ 2144 static void 2145 dnode_dirty_l1range(dnode_t *dn, uint64_t start_blkid, uint64_t end_blkid, 2146 dmu_tx_t *tx) 2147 { 2148 dmu_buf_impl_t *db_search; 2149 dmu_buf_impl_t *db; 2150 avl_index_t where; 2151 2152 db_search = kmem_zalloc(sizeof (dmu_buf_impl_t), KM_SLEEP); 2153 2154 mutex_enter(&dn->dn_dbufs_mtx); 2155 2156 db_search->db_level = 1; 2157 db_search->db_blkid = start_blkid + 1; 2158 db_search->db_state = DB_SEARCH; 2159 for (;;) { 2160 2161 db = avl_find(&dn->dn_dbufs, db_search, &where); 2162 if (db == NULL) 2163 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2164 2165 if (db == NULL || db->db_level != 1 || 2166 db->db_blkid >= end_blkid) { 2167 break; 2168 } 2169 2170 /* 2171 * Setup the next blkid we want to search for. 2172 */ 2173 db_search->db_blkid = db->db_blkid + 1; 2174 ASSERT3U(db->db_blkid, >=, start_blkid); 2175 2176 /* 2177 * If the dbuf transitions to DB_EVICTING while we're trying 2178 * to dirty it, then we will be unable to discover it in 2179 * the dbuf hash table. This will result in a call to 2180 * dbuf_create() which needs to acquire the dn_dbufs_mtx 2181 * lock. To avoid a deadlock, we drop the lock before 2182 * dirtying the level-1 dbuf. 2183 */ 2184 mutex_exit(&dn->dn_dbufs_mtx); 2185 dnode_dirty_l1(dn, db->db_blkid, tx); 2186 mutex_enter(&dn->dn_dbufs_mtx); 2187 } 2188 2189 #ifdef ZFS_DEBUG 2190 /* 2191 * Walk all the in-core level-1 dbufs and verify they have been dirtied. 2192 */ 2193 db_search->db_level = 1; 2194 db_search->db_blkid = start_blkid + 1; 2195 db_search->db_state = DB_SEARCH; 2196 db = avl_find(&dn->dn_dbufs, db_search, &where); 2197 if (db == NULL) 2198 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2199 for (; db != NULL; db = AVL_NEXT(&dn->dn_dbufs, db)) { 2200 if (db->db_level != 1 || db->db_blkid >= end_blkid) 2201 break; 2202 if (db->db_state != DB_EVICTING) 2203 ASSERT(db->db_dirtycnt > 0); 2204 } 2205 #endif 2206 kmem_free(db_search, sizeof (dmu_buf_impl_t)); 2207 mutex_exit(&dn->dn_dbufs_mtx); 2208 } 2209 2210 void 2211 dnode_set_dirtyctx(dnode_t *dn, dmu_tx_t *tx, const void *tag) 2212 { 2213 /* 2214 * Don't set dirtyctx to SYNC if we're just modifying this as we 2215 * initialize the objset. 2216 */ 2217 if (dn->dn_dirtyctx == DN_UNDIRTIED) { 2218 dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset; 2219 2220 if (ds != NULL) { 2221 rrw_enter(&ds->ds_bp_rwlock, RW_READER, tag); 2222 } 2223 if (!BP_IS_HOLE(dn->dn_objset->os_rootbp)) { 2224 if (dmu_tx_is_syncing(tx)) 2225 dn->dn_dirtyctx = DN_DIRTY_SYNC; 2226 else 2227 dn->dn_dirtyctx = DN_DIRTY_OPEN; 2228 dn->dn_dirtyctx_firstset = tag; 2229 } 2230 if (ds != NULL) { 2231 rrw_exit(&ds->ds_bp_rwlock, tag); 2232 } 2233 } 2234 } 2235 2236 static void 2237 dnode_partial_zero(dnode_t *dn, uint64_t off, uint64_t blkoff, uint64_t len, 2238 dmu_tx_t *tx) 2239 { 2240 dmu_buf_impl_t *db; 2241 int res; 2242 2243 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2244 res = dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off), TRUE, FALSE, 2245 FTAG, &db); 2246 rw_exit(&dn->dn_struct_rwlock); 2247 if (res == 0) { 2248 db_lock_type_t dblt; 2249 boolean_t dirty; 2250 2251 dblt = dmu_buf_lock_parent(db, RW_READER, FTAG); 2252 /* don't dirty if not on disk and not dirty */ 2253 dirty = !list_is_empty(&db->db_dirty_records) || 2254 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr)); 2255 dmu_buf_unlock_parent(db, dblt, FTAG); 2256 if (dirty) { 2257 caddr_t data; 2258 2259 dmu_buf_will_dirty(&db->db, tx); 2260 data = db->db.db_data; 2261 memset(data + blkoff, 0, len); 2262 } 2263 dbuf_rele(db, FTAG); 2264 } 2265 } 2266 2267 void 2268 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 2269 { 2270 uint64_t blkoff, blkid, nblks; 2271 int blksz, blkshift, head, tail; 2272 int trunc = FALSE; 2273 int epbs; 2274 2275 blksz = dn->dn_datablksz; 2276 blkshift = dn->dn_datablkshift; 2277 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2278 2279 if (len == DMU_OBJECT_END) { 2280 len = UINT64_MAX - off; 2281 trunc = TRUE; 2282 } 2283 2284 /* 2285 * First, block align the region to free: 2286 */ 2287 if (ISP2(blksz)) { 2288 head = P2NPHASE(off, blksz); 2289 blkoff = P2PHASE(off, blksz); 2290 if ((off >> blkshift) > dn->dn_maxblkid) 2291 return; 2292 } else { 2293 ASSERT(dn->dn_maxblkid == 0); 2294 if (off == 0 && len >= blksz) { 2295 /* 2296 * Freeing the whole block; fast-track this request. 2297 */ 2298 blkid = 0; 2299 nblks = 1; 2300 if (dn->dn_nlevels > 1) { 2301 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2302 dnode_dirty_l1(dn, 0, tx); 2303 rw_exit(&dn->dn_struct_rwlock); 2304 } 2305 goto done; 2306 } else if (off >= blksz) { 2307 /* Freeing past end-of-data */ 2308 return; 2309 } else { 2310 /* Freeing part of the block. */ 2311 head = blksz - off; 2312 ASSERT3U(head, >, 0); 2313 } 2314 blkoff = off; 2315 } 2316 /* zero out any partial block data at the start of the range */ 2317 if (head) { 2318 ASSERT3U(blkoff + head, ==, blksz); 2319 if (len < head) 2320 head = len; 2321 dnode_partial_zero(dn, off, blkoff, head, tx); 2322 off += head; 2323 len -= head; 2324 } 2325 2326 /* If the range was less than one block, we're done */ 2327 if (len == 0) 2328 return; 2329 2330 /* If the remaining range is past end of file, we're done */ 2331 if ((off >> blkshift) > dn->dn_maxblkid) 2332 return; 2333 2334 ASSERT(ISP2(blksz)); 2335 if (trunc) 2336 tail = 0; 2337 else 2338 tail = P2PHASE(len, blksz); 2339 2340 ASSERT0(P2PHASE(off, blksz)); 2341 /* zero out any partial block data at the end of the range */ 2342 if (tail) { 2343 if (len < tail) 2344 tail = len; 2345 dnode_partial_zero(dn, off + len, 0, tail, tx); 2346 len -= tail; 2347 } 2348 2349 /* If the range did not include a full block, we are done */ 2350 if (len == 0) 2351 return; 2352 2353 ASSERT(IS_P2ALIGNED(off, blksz)); 2354 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 2355 blkid = off >> blkshift; 2356 nblks = len >> blkshift; 2357 if (trunc) 2358 nblks += 1; 2359 2360 /* 2361 * Dirty all the indirect blocks in this range. Note that only 2362 * the first and last indirect blocks can actually be written 2363 * (if they were partially freed) -- they must be dirtied, even if 2364 * they do not exist on disk yet. The interior blocks will 2365 * be freed by free_children(), so they will not actually be written. 2366 * Even though these interior blocks will not be written, we 2367 * dirty them for two reasons: 2368 * 2369 * - It ensures that the indirect blocks remain in memory until 2370 * syncing context. (They have already been prefetched by 2371 * dmu_tx_hold_free(), so we don't have to worry about reading 2372 * them serially here.) 2373 * 2374 * - The dirty space accounting will put pressure on the txg sync 2375 * mechanism to begin syncing, and to delay transactions if there 2376 * is a large amount of freeing. Even though these indirect 2377 * blocks will not be written, we could need to write the same 2378 * amount of space if we copy the freed BPs into deadlists. 2379 */ 2380 if (dn->dn_nlevels > 1) { 2381 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2382 uint64_t first, last; 2383 2384 first = blkid >> epbs; 2385 dnode_dirty_l1(dn, first, tx); 2386 if (trunc) 2387 last = dn->dn_maxblkid >> epbs; 2388 else 2389 last = (blkid + nblks - 1) >> epbs; 2390 if (last != first) 2391 dnode_dirty_l1(dn, last, tx); 2392 2393 dnode_dirty_l1range(dn, first, last, tx); 2394 2395 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 2396 SPA_BLKPTRSHIFT; 2397 for (uint64_t i = first + 1; i < last; i++) { 2398 /* 2399 * Set i to the blockid of the next non-hole 2400 * level-1 indirect block at or after i. Note 2401 * that dnode_next_offset() operates in terms of 2402 * level-0-equivalent bytes. 2403 */ 2404 uint64_t ibyte = i << shift; 2405 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, 2406 &ibyte, 2, 1, 0); 2407 i = ibyte >> shift; 2408 if (i >= last) 2409 break; 2410 2411 /* 2412 * Normally we should not see an error, either 2413 * from dnode_next_offset() or dbuf_hold_level() 2414 * (except for ESRCH from dnode_next_offset). 2415 * If there is an i/o error, then when we read 2416 * this block in syncing context, it will use 2417 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according 2418 * to the "failmode" property. dnode_next_offset() 2419 * doesn't have a flag to indicate MUSTSUCCEED. 2420 */ 2421 if (err != 0) 2422 break; 2423 2424 dnode_dirty_l1(dn, i, tx); 2425 } 2426 rw_exit(&dn->dn_struct_rwlock); 2427 } 2428 2429 done: 2430 /* 2431 * Add this range to the dnode range list. 2432 * We will finish up this free operation in the syncing phase. 2433 */ 2434 mutex_enter(&dn->dn_mtx); 2435 { 2436 int txgoff = tx->tx_txg & TXG_MASK; 2437 if (dn->dn_free_ranges[txgoff] == NULL) { 2438 dn->dn_free_ranges[txgoff] = range_tree_create(NULL, 2439 RANGE_SEG64, NULL, 0, 0); 2440 } 2441 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 2442 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 2443 } 2444 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 2445 (u_longlong_t)blkid, (u_longlong_t)nblks, 2446 (u_longlong_t)tx->tx_txg); 2447 mutex_exit(&dn->dn_mtx); 2448 2449 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 2450 dnode_setdirty(dn, tx); 2451 } 2452 2453 static boolean_t 2454 dnode_spill_freed(dnode_t *dn) 2455 { 2456 int i; 2457 2458 mutex_enter(&dn->dn_mtx); 2459 for (i = 0; i < TXG_SIZE; i++) { 2460 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 2461 break; 2462 } 2463 mutex_exit(&dn->dn_mtx); 2464 return (i < TXG_SIZE); 2465 } 2466 2467 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 2468 uint64_t 2469 dnode_block_freed(dnode_t *dn, uint64_t blkid) 2470 { 2471 int i; 2472 2473 if (blkid == DMU_BONUS_BLKID) 2474 return (FALSE); 2475 2476 if (dn->dn_free_txg) 2477 return (TRUE); 2478 2479 if (blkid == DMU_SPILL_BLKID) 2480 return (dnode_spill_freed(dn)); 2481 2482 mutex_enter(&dn->dn_mtx); 2483 for (i = 0; i < TXG_SIZE; i++) { 2484 if (dn->dn_free_ranges[i] != NULL && 2485 range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 2486 break; 2487 } 2488 mutex_exit(&dn->dn_mtx); 2489 return (i < TXG_SIZE); 2490 } 2491 2492 /* call from syncing context when we actually write/free space for this dnode */ 2493 void 2494 dnode_diduse_space(dnode_t *dn, int64_t delta) 2495 { 2496 uint64_t space; 2497 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 2498 dn, dn->dn_phys, 2499 (u_longlong_t)dn->dn_phys->dn_used, 2500 (longlong_t)delta); 2501 2502 mutex_enter(&dn->dn_mtx); 2503 space = DN_USED_BYTES(dn->dn_phys); 2504 if (delta > 0) { 2505 ASSERT3U(space + delta, >=, space); /* no overflow */ 2506 } else { 2507 ASSERT3U(space, >=, -delta); /* no underflow */ 2508 } 2509 space += delta; 2510 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 2511 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 2512 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 2513 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 2514 } else { 2515 dn->dn_phys->dn_used = space; 2516 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 2517 } 2518 mutex_exit(&dn->dn_mtx); 2519 } 2520 2521 /* 2522 * Scans a block at the indicated "level" looking for a hole or data, 2523 * depending on 'flags'. 2524 * 2525 * If level > 0, then we are scanning an indirect block looking at its 2526 * pointers. If level == 0, then we are looking at a block of dnodes. 2527 * 2528 * If we don't find what we are looking for in the block, we return ESRCH. 2529 * Otherwise, return with *offset pointing to the beginning (if searching 2530 * forwards) or end (if searching backwards) of the range covered by the 2531 * block pointer we matched on (or dnode). 2532 * 2533 * The basic search algorithm used below by dnode_next_offset() is to 2534 * use this function to search up the block tree (widen the search) until 2535 * we find something (i.e., we don't return ESRCH) and then search back 2536 * down the tree (narrow the search) until we reach our original search 2537 * level. 2538 */ 2539 static int 2540 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 2541 int lvl, uint64_t blkfill, uint64_t txg) 2542 { 2543 dmu_buf_impl_t *db = NULL; 2544 void *data = NULL; 2545 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 2546 uint64_t epb = 1ULL << epbs; 2547 uint64_t minfill, maxfill; 2548 boolean_t hole; 2549 int i, inc, error, span; 2550 2551 ASSERT(RW_LOCK_HELD(&dn->dn_struct_rwlock)); 2552 2553 hole = ((flags & DNODE_FIND_HOLE) != 0); 2554 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 2555 ASSERT(txg == 0 || !hole); 2556 2557 if (lvl == dn->dn_phys->dn_nlevels) { 2558 error = 0; 2559 epb = dn->dn_phys->dn_nblkptr; 2560 data = dn->dn_phys->dn_blkptr; 2561 } else { 2562 uint64_t blkid = dbuf_whichblock(dn, lvl, *offset); 2563 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FALSE, FTAG, &db); 2564 if (error) { 2565 if (error != ENOENT) 2566 return (error); 2567 if (hole) 2568 return (0); 2569 /* 2570 * This can only happen when we are searching up 2571 * the block tree for data. We don't really need to 2572 * adjust the offset, as we will just end up looking 2573 * at the pointer to this block in its parent, and its 2574 * going to be unallocated, so we will skip over it. 2575 */ 2576 return (SET_ERROR(ESRCH)); 2577 } 2578 error = dbuf_read(db, NULL, 2579 DB_RF_CANFAIL | DB_RF_HAVESTRUCT | 2580 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH); 2581 if (error) { 2582 dbuf_rele(db, FTAG); 2583 return (error); 2584 } 2585 data = db->db.db_data; 2586 rw_enter(&db->db_rwlock, RW_READER); 2587 } 2588 2589 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 2590 BP_GET_LOGICAL_BIRTH(db->db_blkptr) <= txg || 2591 BP_IS_HOLE(db->db_blkptr))) { 2592 /* 2593 * This can only happen when we are searching up the tree 2594 * and these conditions mean that we need to keep climbing. 2595 */ 2596 error = SET_ERROR(ESRCH); 2597 } else if (lvl == 0) { 2598 dnode_phys_t *dnp = data; 2599 2600 ASSERT(dn->dn_type == DMU_OT_DNODE); 2601 ASSERT(!(flags & DNODE_FIND_BACKWARDS)); 2602 2603 for (i = (*offset >> DNODE_SHIFT) & (blkfill - 1); 2604 i < blkfill; i += dnp[i].dn_extra_slots + 1) { 2605 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 2606 break; 2607 } 2608 2609 if (i == blkfill) 2610 error = SET_ERROR(ESRCH); 2611 2612 *offset = (*offset & ~(DNODE_BLOCK_SIZE - 1)) + 2613 (i << DNODE_SHIFT); 2614 } else { 2615 blkptr_t *bp = data; 2616 uint64_t start = *offset; 2617 span = (lvl - 1) * epbs + dn->dn_datablkshift; 2618 minfill = 0; 2619 maxfill = blkfill << ((lvl - 1) * epbs); 2620 2621 if (hole) 2622 maxfill--; 2623 else 2624 minfill++; 2625 2626 if (span >= 8 * sizeof (*offset)) { 2627 /* This only happens on the highest indirection level */ 2628 ASSERT3U((lvl - 1), ==, dn->dn_phys->dn_nlevels - 1); 2629 *offset = 0; 2630 } else { 2631 *offset = *offset >> span; 2632 } 2633 2634 for (i = BF64_GET(*offset, 0, epbs); 2635 i >= 0 && i < epb; i += inc) { 2636 if (BP_GET_FILL(&bp[i]) >= minfill && 2637 BP_GET_FILL(&bp[i]) <= maxfill && 2638 (hole || BP_GET_LOGICAL_BIRTH(&bp[i]) > txg)) 2639 break; 2640 if (inc > 0 || *offset > 0) 2641 *offset += inc; 2642 } 2643 2644 if (span >= 8 * sizeof (*offset)) { 2645 *offset = start; 2646 } else { 2647 *offset = *offset << span; 2648 } 2649 2650 if (inc < 0) { 2651 /* traversing backwards; position offset at the end */ 2652 if (span < 8 * sizeof (*offset)) 2653 *offset = MIN(*offset + (1ULL << span) - 1, 2654 start); 2655 } else if (*offset < start) { 2656 *offset = start; 2657 } 2658 if (i < 0 || i >= epb) 2659 error = SET_ERROR(ESRCH); 2660 } 2661 2662 if (db != NULL) { 2663 rw_exit(&db->db_rwlock); 2664 dbuf_rele(db, FTAG); 2665 } 2666 2667 return (error); 2668 } 2669 2670 /* 2671 * Find the next hole, data, or sparse region at or after *offset. 2672 * The value 'blkfill' tells us how many items we expect to find 2673 * in an L0 data block; this value is 1 for normal objects, 2674 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 2675 * DNODES_PER_BLOCK when searching for sparse regions thereof. 2676 * 2677 * Examples: 2678 * 2679 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 2680 * Finds the next/previous hole/data in a file. 2681 * Used in dmu_offset_next(). 2682 * 2683 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 2684 * Finds the next free/allocated dnode an objset's meta-dnode. 2685 * Only finds objects that have new contents since txg (ie. 2686 * bonus buffer changes and content removal are ignored). 2687 * Used in dmu_object_next(). 2688 * 2689 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 2690 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 2691 * Used in dmu_object_alloc(). 2692 */ 2693 int 2694 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 2695 int minlvl, uint64_t blkfill, uint64_t txg) 2696 { 2697 uint64_t initial_offset = *offset; 2698 int lvl, maxlvl; 2699 int error = 0; 2700 2701 if (!(flags & DNODE_FIND_HAVELOCK)) 2702 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2703 2704 if (dn->dn_phys->dn_nlevels == 0) { 2705 error = SET_ERROR(ESRCH); 2706 goto out; 2707 } 2708 2709 if (dn->dn_datablkshift == 0) { 2710 if (*offset < dn->dn_datablksz) { 2711 if (flags & DNODE_FIND_HOLE) 2712 *offset = dn->dn_datablksz; 2713 } else { 2714 error = SET_ERROR(ESRCH); 2715 } 2716 goto out; 2717 } 2718 2719 maxlvl = dn->dn_phys->dn_nlevels; 2720 2721 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 2722 error = dnode_next_offset_level(dn, 2723 flags, offset, lvl, blkfill, txg); 2724 if (error != ESRCH) 2725 break; 2726 } 2727 2728 while (error == 0 && --lvl >= minlvl) { 2729 error = dnode_next_offset_level(dn, 2730 flags, offset, lvl, blkfill, txg); 2731 } 2732 2733 /* 2734 * There's always a "virtual hole" at the end of the object, even 2735 * if all BP's which physically exist are non-holes. 2736 */ 2737 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 && 2738 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) { 2739 error = 0; 2740 } 2741 2742 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 2743 initial_offset < *offset : initial_offset > *offset)) 2744 error = SET_ERROR(ESRCH); 2745 out: 2746 if (!(flags & DNODE_FIND_HAVELOCK)) 2747 rw_exit(&dn->dn_struct_rwlock); 2748 2749 return (error); 2750 } 2751 2752 #if defined(_KERNEL) 2753 EXPORT_SYMBOL(dnode_hold); 2754 EXPORT_SYMBOL(dnode_rele); 2755 EXPORT_SYMBOL(dnode_set_nlevels); 2756 EXPORT_SYMBOL(dnode_set_blksz); 2757 EXPORT_SYMBOL(dnode_free_range); 2758 EXPORT_SYMBOL(dnode_evict_dbufs); 2759 EXPORT_SYMBOL(dnode_evict_bonus); 2760 #endif 2761 2762 ZFS_MODULE_PARAM(zfs, zfs_, default_bs, INT, ZMOD_RW, 2763 "Default dnode block shift"); 2764 ZFS_MODULE_PARAM(zfs, zfs_, default_ibs, INT, ZMOD_RW, 2765 "Default dnode indirect block shift"); 2766