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