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_OTN_UINT64_METADATA && bonuslen == 0) || 724 (bonustype != DMU_OT_NONE && bonuslen != 0)); 725 ASSERT(DMU_OT_IS_VALID(bonustype)); 726 ASSERT3U(bonuslen, <=, DN_SLOTS_TO_BONUSLEN(dn_slots)); 727 ASSERT(dn->dn_type == DMU_OT_NONE); 728 ASSERT0(dn->dn_maxblkid); 729 ASSERT0(dn->dn_allocated_txg); 730 ASSERT0(dn->dn_assigned_txg); 731 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 732 ASSERT3U(zfs_refcount_count(&dn->dn_holds), <=, 1); 733 ASSERT(avl_is_empty(&dn->dn_dbufs)); 734 735 for (i = 0; i < TXG_SIZE; i++) { 736 ASSERT0(dn->dn_next_nblkptr[i]); 737 ASSERT0(dn->dn_next_nlevels[i]); 738 ASSERT0(dn->dn_next_indblkshift[i]); 739 ASSERT0(dn->dn_next_bonuslen[i]); 740 ASSERT0(dn->dn_next_bonustype[i]); 741 ASSERT0(dn->dn_rm_spillblk[i]); 742 ASSERT0(dn->dn_next_blksz[i]); 743 ASSERT0(dn->dn_next_maxblkid[i]); 744 ASSERT(!multilist_link_active(&dn->dn_dirty_link[i])); 745 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 746 ASSERT3P(dn->dn_free_ranges[i], ==, NULL); 747 } 748 749 dn->dn_type = ot; 750 dnode_setdblksz(dn, blocksize); 751 dn->dn_indblkshift = ibs; 752 dn->dn_nlevels = 1; 753 dn->dn_num_slots = dn_slots; 754 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 755 dn->dn_nblkptr = 1; 756 else { 757 dn->dn_nblkptr = MIN(DN_MAX_NBLKPTR, 758 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 759 SPA_BLKPTRSHIFT)); 760 } 761 762 dn->dn_bonustype = bonustype; 763 dn->dn_bonuslen = bonuslen; 764 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 765 dn->dn_compress = ZIO_COMPRESS_INHERIT; 766 dn->dn_dirtyctx = 0; 767 768 dn->dn_free_txg = 0; 769 dn->dn_dirtyctx_firstset = NULL; 770 dn->dn_dirty_txg = 0; 771 772 dn->dn_allocated_txg = tx->tx_txg; 773 dn->dn_id_flags = 0; 774 775 dnode_setdirty(dn, tx); 776 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 777 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 778 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 779 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 780 } 781 782 void 783 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 784 dmu_object_type_t bonustype, int bonuslen, int dn_slots, 785 boolean_t keep_spill, dmu_tx_t *tx) 786 { 787 int nblkptr; 788 789 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 790 ASSERT3U(blocksize, <=, 791 spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 792 ASSERT0(blocksize % SPA_MINBLOCKSIZE); 793 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 794 ASSERT(tx->tx_txg != 0); 795 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 796 (bonustype != DMU_OT_NONE && bonuslen != 0) || 797 (bonustype == DMU_OT_SA && bonuslen == 0)); 798 ASSERT(DMU_OT_IS_VALID(bonustype)); 799 ASSERT3U(bonuslen, <=, 800 DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(dn->dn_objset)))); 801 ASSERT3U(bonuslen, <=, DN_BONUS_SIZE(dn_slots << DNODE_SHIFT)); 802 803 dnode_free_interior_slots(dn); 804 DNODE_STAT_BUMP(dnode_reallocate); 805 806 /* clean up any unreferenced dbufs */ 807 dnode_evict_dbufs(dn); 808 809 dn->dn_id_flags = 0; 810 811 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 812 dnode_setdirty(dn, tx); 813 if (dn->dn_datablksz != blocksize) { 814 /* change blocksize */ 815 ASSERT0(dn->dn_maxblkid); 816 ASSERT(BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 817 dnode_block_freed(dn, 0)); 818 819 dnode_setdblksz(dn, blocksize); 820 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = blocksize; 821 } 822 if (dn->dn_bonuslen != bonuslen) 823 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = bonuslen; 824 825 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 826 nblkptr = 1; 827 else 828 nblkptr = MIN(DN_MAX_NBLKPTR, 829 1 + ((DN_SLOTS_TO_BONUSLEN(dn_slots) - bonuslen) >> 830 SPA_BLKPTRSHIFT)); 831 if (dn->dn_bonustype != bonustype) 832 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = bonustype; 833 if (dn->dn_nblkptr != nblkptr) 834 dn->dn_next_nblkptr[tx->tx_txg & TXG_MASK] = nblkptr; 835 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR && !keep_spill) { 836 dbuf_rm_spill(dn, tx); 837 dnode_rm_spill(dn, tx); 838 } 839 840 rw_exit(&dn->dn_struct_rwlock); 841 842 /* change type */ 843 dn->dn_type = ot; 844 845 /* change bonus size and type */ 846 mutex_enter(&dn->dn_mtx); 847 dn->dn_bonustype = bonustype; 848 dn->dn_bonuslen = bonuslen; 849 dn->dn_num_slots = dn_slots; 850 dn->dn_nblkptr = nblkptr; 851 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 852 dn->dn_compress = ZIO_COMPRESS_INHERIT; 853 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 854 855 /* fix up the bonus db_size */ 856 if (dn->dn_bonus) { 857 dn->dn_bonus->db.db_size = 858 DN_SLOTS_TO_BONUSLEN(dn->dn_num_slots) - 859 (dn->dn_nblkptr-1) * sizeof (blkptr_t); 860 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 861 } 862 863 dn->dn_allocated_txg = tx->tx_txg; 864 mutex_exit(&dn->dn_mtx); 865 } 866 867 #ifdef _KERNEL 868 static void 869 dnode_move_impl(dnode_t *odn, dnode_t *ndn) 870 { 871 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 872 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 873 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 874 875 /* Copy fields. */ 876 ndn->dn_objset = odn->dn_objset; 877 ndn->dn_object = odn->dn_object; 878 ndn->dn_dbuf = odn->dn_dbuf; 879 ndn->dn_handle = odn->dn_handle; 880 ndn->dn_phys = odn->dn_phys; 881 ndn->dn_type = odn->dn_type; 882 ndn->dn_bonuslen = odn->dn_bonuslen; 883 ndn->dn_bonustype = odn->dn_bonustype; 884 ndn->dn_nblkptr = odn->dn_nblkptr; 885 ndn->dn_checksum = odn->dn_checksum; 886 ndn->dn_compress = odn->dn_compress; 887 ndn->dn_nlevels = odn->dn_nlevels; 888 ndn->dn_indblkshift = odn->dn_indblkshift; 889 ndn->dn_datablkshift = odn->dn_datablkshift; 890 ndn->dn_datablkszsec = odn->dn_datablkszsec; 891 ndn->dn_datablksz = odn->dn_datablksz; 892 ndn->dn_maxblkid = odn->dn_maxblkid; 893 ndn->dn_num_slots = odn->dn_num_slots; 894 memcpy(ndn->dn_next_type, odn->dn_next_type, 895 sizeof (odn->dn_next_type)); 896 memcpy(ndn->dn_next_nblkptr, odn->dn_next_nblkptr, 897 sizeof (odn->dn_next_nblkptr)); 898 memcpy(ndn->dn_next_nlevels, odn->dn_next_nlevels, 899 sizeof (odn->dn_next_nlevels)); 900 memcpy(ndn->dn_next_indblkshift, odn->dn_next_indblkshift, 901 sizeof (odn->dn_next_indblkshift)); 902 memcpy(ndn->dn_next_bonustype, odn->dn_next_bonustype, 903 sizeof (odn->dn_next_bonustype)); 904 memcpy(ndn->dn_rm_spillblk, odn->dn_rm_spillblk, 905 sizeof (odn->dn_rm_spillblk)); 906 memcpy(ndn->dn_next_bonuslen, odn->dn_next_bonuslen, 907 sizeof (odn->dn_next_bonuslen)); 908 memcpy(ndn->dn_next_blksz, odn->dn_next_blksz, 909 sizeof (odn->dn_next_blksz)); 910 memcpy(ndn->dn_next_maxblkid, odn->dn_next_maxblkid, 911 sizeof (odn->dn_next_maxblkid)); 912 for (int i = 0; i < TXG_SIZE; i++) { 913 list_move_tail(&ndn->dn_dirty_records[i], 914 &odn->dn_dirty_records[i]); 915 } 916 memcpy(ndn->dn_free_ranges, odn->dn_free_ranges, 917 sizeof (odn->dn_free_ranges)); 918 ndn->dn_allocated_txg = odn->dn_allocated_txg; 919 ndn->dn_free_txg = odn->dn_free_txg; 920 ndn->dn_assigned_txg = odn->dn_assigned_txg; 921 ndn->dn_dirty_txg = odn->dn_dirty_txg; 922 ndn->dn_dirtyctx = odn->dn_dirtyctx; 923 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 924 ASSERT(zfs_refcount_count(&odn->dn_tx_holds) == 0); 925 zfs_refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 926 ASSERT(avl_is_empty(&ndn->dn_dbufs)); 927 avl_swap(&ndn->dn_dbufs, &odn->dn_dbufs); 928 ndn->dn_dbufs_count = odn->dn_dbufs_count; 929 ndn->dn_bonus = odn->dn_bonus; 930 ndn->dn_have_spill = odn->dn_have_spill; 931 ndn->dn_zio = odn->dn_zio; 932 ndn->dn_oldused = odn->dn_oldused; 933 ndn->dn_oldflags = odn->dn_oldflags; 934 ndn->dn_olduid = odn->dn_olduid; 935 ndn->dn_oldgid = odn->dn_oldgid; 936 ndn->dn_oldprojid = odn->dn_oldprojid; 937 ndn->dn_newuid = odn->dn_newuid; 938 ndn->dn_newgid = odn->dn_newgid; 939 ndn->dn_newprojid = odn->dn_newprojid; 940 ndn->dn_id_flags = odn->dn_id_flags; 941 dmu_zfetch_init(&ndn->dn_zfetch, ndn); 942 943 /* 944 * Update back pointers. Updating the handle fixes the back pointer of 945 * every descendant dbuf as well as the bonus dbuf. 946 */ 947 ASSERT(ndn->dn_handle->dnh_dnode == odn); 948 ndn->dn_handle->dnh_dnode = ndn; 949 950 /* 951 * Invalidate the original dnode by clearing all of its back pointers. 952 */ 953 odn->dn_dbuf = NULL; 954 odn->dn_handle = NULL; 955 avl_create(&odn->dn_dbufs, dbuf_compare, sizeof (dmu_buf_impl_t), 956 offsetof(dmu_buf_impl_t, db_link)); 957 odn->dn_dbufs_count = 0; 958 odn->dn_bonus = NULL; 959 dmu_zfetch_fini(&odn->dn_zfetch); 960 961 /* 962 * Set the low bit of the objset pointer to ensure that dnode_move() 963 * recognizes the dnode as invalid in any subsequent callback. 964 */ 965 POINTER_INVALIDATE(&odn->dn_objset); 966 967 /* 968 * Satisfy the destructor. 969 */ 970 for (int i = 0; i < TXG_SIZE; i++) { 971 list_create(&odn->dn_dirty_records[i], 972 sizeof (dbuf_dirty_record_t), 973 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 974 odn->dn_free_ranges[i] = NULL; 975 odn->dn_next_nlevels[i] = 0; 976 odn->dn_next_indblkshift[i] = 0; 977 odn->dn_next_bonustype[i] = 0; 978 odn->dn_rm_spillblk[i] = 0; 979 odn->dn_next_bonuslen[i] = 0; 980 odn->dn_next_blksz[i] = 0; 981 } 982 odn->dn_allocated_txg = 0; 983 odn->dn_free_txg = 0; 984 odn->dn_assigned_txg = 0; 985 odn->dn_dirty_txg = 0; 986 odn->dn_dirtyctx = 0; 987 odn->dn_dirtyctx_firstset = NULL; 988 odn->dn_have_spill = B_FALSE; 989 odn->dn_zio = NULL; 990 odn->dn_oldused = 0; 991 odn->dn_oldflags = 0; 992 odn->dn_olduid = 0; 993 odn->dn_oldgid = 0; 994 odn->dn_oldprojid = ZFS_DEFAULT_PROJID; 995 odn->dn_newuid = 0; 996 odn->dn_newgid = 0; 997 odn->dn_newprojid = ZFS_DEFAULT_PROJID; 998 odn->dn_id_flags = 0; 999 1000 /* 1001 * Mark the dnode. 1002 */ 1003 ndn->dn_moved = 1; 1004 odn->dn_moved = (uint8_t)-1; 1005 } 1006 1007 static kmem_cbrc_t 1008 dnode_move(void *buf, void *newbuf, size_t size, void *arg) 1009 { 1010 dnode_t *odn = buf, *ndn = newbuf; 1011 objset_t *os; 1012 int64_t refcount; 1013 uint32_t dbufs; 1014 1015 /* 1016 * The dnode is on the objset's list of known dnodes if the objset 1017 * pointer is valid. We set the low bit of the objset pointer when 1018 * freeing the dnode to invalidate it, and the memory patterns written 1019 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 1020 * A newly created dnode sets the objset pointer last of all to indicate 1021 * that the dnode is known and in a valid state to be moved by this 1022 * function. 1023 */ 1024 os = odn->dn_objset; 1025 if (!POINTER_IS_VALID(os)) { 1026 DNODE_STAT_BUMP(dnode_move_invalid); 1027 return (KMEM_CBRC_DONT_KNOW); 1028 } 1029 1030 /* 1031 * Ensure that the objset does not go away during the move. 1032 */ 1033 rw_enter(&os_lock, RW_WRITER); 1034 if (os != odn->dn_objset) { 1035 rw_exit(&os_lock); 1036 DNODE_STAT_BUMP(dnode_move_recheck1); 1037 return (KMEM_CBRC_DONT_KNOW); 1038 } 1039 1040 /* 1041 * If the dnode is still valid, then so is the objset. We know that no 1042 * valid objset can be freed while we hold os_lock, so we can safely 1043 * ensure that the objset remains in use. 1044 */ 1045 mutex_enter(&os->os_lock); 1046 1047 /* 1048 * Recheck the objset pointer in case the dnode was removed just before 1049 * acquiring the lock. 1050 */ 1051 if (os != odn->dn_objset) { 1052 mutex_exit(&os->os_lock); 1053 rw_exit(&os_lock); 1054 DNODE_STAT_BUMP(dnode_move_recheck2); 1055 return (KMEM_CBRC_DONT_KNOW); 1056 } 1057 1058 /* 1059 * At this point we know that as long as we hold os->os_lock, the dnode 1060 * cannot be freed and fields within the dnode can be safely accessed. 1061 * The objset listing this dnode cannot go away as long as this dnode is 1062 * on its list. 1063 */ 1064 rw_exit(&os_lock); 1065 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 1066 mutex_exit(&os->os_lock); 1067 DNODE_STAT_BUMP(dnode_move_special); 1068 return (KMEM_CBRC_NO); 1069 } 1070 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 1071 1072 /* 1073 * Lock the dnode handle to prevent the dnode from obtaining any new 1074 * holds. This also prevents the descendant dbufs and the bonus dbuf 1075 * from accessing the dnode, so that we can discount their holds. The 1076 * handle is safe to access because we know that while the dnode cannot 1077 * go away, neither can its handle. Once we hold dnh_zrlock, we can 1078 * safely move any dnode referenced only by dbufs. 1079 */ 1080 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 1081 mutex_exit(&os->os_lock); 1082 DNODE_STAT_BUMP(dnode_move_handle); 1083 return (KMEM_CBRC_LATER); 1084 } 1085 1086 /* 1087 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 1088 * We need to guarantee that there is a hold for every dbuf in order to 1089 * determine whether the dnode is actively referenced. Falsely matching 1090 * a dbuf to an active hold would lead to an unsafe move. It's possible 1091 * that a thread already having an active dnode hold is about to add a 1092 * dbuf, and we can't compare hold and dbuf counts while the add is in 1093 * progress. 1094 */ 1095 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 1096 zrl_exit(&odn->dn_handle->dnh_zrlock); 1097 mutex_exit(&os->os_lock); 1098 DNODE_STAT_BUMP(dnode_move_rwlock); 1099 return (KMEM_CBRC_LATER); 1100 } 1101 1102 /* 1103 * A dbuf may be removed (evicted) without an active dnode hold. In that 1104 * case, the dbuf count is decremented under the handle lock before the 1105 * dbuf's hold is released. This order ensures that if we count the hold 1106 * after the dbuf is removed but before its hold is released, we will 1107 * treat the unmatched hold as active and exit safely. If we count the 1108 * hold before the dbuf is removed, the hold is discounted, and the 1109 * removal is blocked until the move completes. 1110 */ 1111 refcount = zfs_refcount_count(&odn->dn_holds); 1112 ASSERT(refcount >= 0); 1113 dbufs = DN_DBUFS_COUNT(odn); 1114 1115 /* We can't have more dbufs than dnode holds. */ 1116 ASSERT3U(dbufs, <=, refcount); 1117 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 1118 uint32_t, dbufs); 1119 1120 if (refcount > dbufs) { 1121 rw_exit(&odn->dn_struct_rwlock); 1122 zrl_exit(&odn->dn_handle->dnh_zrlock); 1123 mutex_exit(&os->os_lock); 1124 DNODE_STAT_BUMP(dnode_move_active); 1125 return (KMEM_CBRC_LATER); 1126 } 1127 1128 rw_exit(&odn->dn_struct_rwlock); 1129 1130 /* 1131 * At this point we know that anyone with a hold on the dnode is not 1132 * actively referencing it. The dnode is known and in a valid state to 1133 * move. We're holding the locks needed to execute the critical section. 1134 */ 1135 dnode_move_impl(odn, ndn); 1136 1137 list_link_replace(&odn->dn_link, &ndn->dn_link); 1138 /* If the dnode was safe to move, the refcount cannot have changed. */ 1139 ASSERT(refcount == zfs_refcount_count(&ndn->dn_holds)); 1140 ASSERT(dbufs == DN_DBUFS_COUNT(ndn)); 1141 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 1142 mutex_exit(&os->os_lock); 1143 1144 return (KMEM_CBRC_YES); 1145 } 1146 #endif /* _KERNEL */ 1147 1148 static void 1149 dnode_slots_hold(dnode_children_t *children, int idx, int slots) 1150 { 1151 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1152 1153 for (int i = idx; i < idx + slots; i++) { 1154 dnode_handle_t *dnh = &children->dnc_children[i]; 1155 zrl_add(&dnh->dnh_zrlock); 1156 } 1157 } 1158 1159 static void 1160 dnode_slots_rele(dnode_children_t *children, int idx, int slots) 1161 { 1162 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1163 1164 for (int i = idx; i < idx + slots; i++) { 1165 dnode_handle_t *dnh = &children->dnc_children[i]; 1166 1167 if (zrl_is_locked(&dnh->dnh_zrlock)) 1168 zrl_exit(&dnh->dnh_zrlock); 1169 else 1170 zrl_remove(&dnh->dnh_zrlock); 1171 } 1172 } 1173 1174 static int 1175 dnode_slots_tryenter(dnode_children_t *children, int idx, int slots) 1176 { 1177 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1178 1179 for (int i = idx; i < idx + slots; i++) { 1180 dnode_handle_t *dnh = &children->dnc_children[i]; 1181 1182 if (!zrl_tryenter(&dnh->dnh_zrlock)) { 1183 for (int j = idx; j < i; j++) { 1184 dnh = &children->dnc_children[j]; 1185 zrl_exit(&dnh->dnh_zrlock); 1186 } 1187 1188 return (0); 1189 } 1190 } 1191 1192 return (1); 1193 } 1194 1195 static void 1196 dnode_set_slots(dnode_children_t *children, int idx, int slots, void *ptr) 1197 { 1198 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1199 1200 for (int i = idx; i < idx + slots; i++) { 1201 dnode_handle_t *dnh = &children->dnc_children[i]; 1202 dnh->dnh_dnode = ptr; 1203 } 1204 } 1205 1206 static boolean_t 1207 dnode_check_slots_free(dnode_children_t *children, int idx, int slots) 1208 { 1209 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1210 1211 /* 1212 * If all dnode slots are either already free or 1213 * evictable return B_TRUE. 1214 */ 1215 for (int i = idx; i < idx + slots; i++) { 1216 dnode_handle_t *dnh = &children->dnc_children[i]; 1217 dnode_t *dn = dnh->dnh_dnode; 1218 1219 if (dn == DN_SLOT_FREE) { 1220 continue; 1221 } else if (DN_SLOT_IS_PTR(dn)) { 1222 mutex_enter(&dn->dn_mtx); 1223 boolean_t can_free = (dn->dn_type == DMU_OT_NONE && 1224 zfs_refcount_is_zero(&dn->dn_holds) && 1225 !DNODE_IS_DIRTY(dn)); 1226 mutex_exit(&dn->dn_mtx); 1227 1228 if (!can_free) 1229 return (B_FALSE); 1230 else 1231 continue; 1232 } else { 1233 return (B_FALSE); 1234 } 1235 } 1236 1237 return (B_TRUE); 1238 } 1239 1240 static uint_t 1241 dnode_reclaim_slots(dnode_children_t *children, int idx, int slots) 1242 { 1243 uint_t reclaimed = 0; 1244 1245 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1246 1247 for (int i = idx; i < idx + slots; i++) { 1248 dnode_handle_t *dnh = &children->dnc_children[i]; 1249 1250 ASSERT(zrl_is_locked(&dnh->dnh_zrlock)); 1251 1252 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1253 ASSERT3S(dnh->dnh_dnode->dn_type, ==, DMU_OT_NONE); 1254 dnode_destroy(dnh->dnh_dnode); 1255 dnh->dnh_dnode = DN_SLOT_FREE; 1256 reclaimed++; 1257 } 1258 } 1259 1260 return (reclaimed); 1261 } 1262 1263 void 1264 dnode_free_interior_slots(dnode_t *dn) 1265 { 1266 dnode_children_t *children = dmu_buf_get_user(&dn->dn_dbuf->db); 1267 int epb = dn->dn_dbuf->db.db_size >> DNODE_SHIFT; 1268 int idx = (dn->dn_object & (epb - 1)) + 1; 1269 int slots = dn->dn_num_slots - 1; 1270 1271 if (slots == 0) 1272 return; 1273 1274 ASSERT3S(idx + slots, <=, DNODES_PER_BLOCK); 1275 1276 while (!dnode_slots_tryenter(children, idx, slots)) { 1277 DNODE_STAT_BUMP(dnode_free_interior_lock_retry); 1278 kpreempt(KPREEMPT_SYNC); 1279 } 1280 1281 dnode_set_slots(children, idx, slots, DN_SLOT_FREE); 1282 dnode_slots_rele(children, idx, slots); 1283 } 1284 1285 void 1286 dnode_special_close(dnode_handle_t *dnh) 1287 { 1288 dnode_t *dn = dnh->dnh_dnode; 1289 1290 /* 1291 * Ensure dnode_rele_and_unlock() has released dn_mtx, after final 1292 * zfs_refcount_remove() 1293 */ 1294 mutex_enter(&dn->dn_mtx); 1295 if (zfs_refcount_count(&dn->dn_holds) > 0) 1296 cv_wait(&dn->dn_nodnholds, &dn->dn_mtx); 1297 mutex_exit(&dn->dn_mtx); 1298 ASSERT3U(zfs_refcount_count(&dn->dn_holds), ==, 0); 1299 1300 ASSERT(dn->dn_dbuf == NULL || 1301 dmu_buf_get_user(&dn->dn_dbuf->db) == NULL); 1302 zrl_add(&dnh->dnh_zrlock); 1303 dnode_destroy(dn); /* implicit zrl_remove() */ 1304 zrl_destroy(&dnh->dnh_zrlock); 1305 dnh->dnh_dnode = NULL; 1306 } 1307 1308 void 1309 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 1310 dnode_handle_t *dnh) 1311 { 1312 dnode_t *dn; 1313 1314 zrl_init(&dnh->dnh_zrlock); 1315 VERIFY3U(1, ==, zrl_tryenter(&dnh->dnh_zrlock)); 1316 1317 dn = dnode_create(os, dnp, NULL, object, dnh); 1318 DNODE_VERIFY(dn); 1319 1320 zrl_exit(&dnh->dnh_zrlock); 1321 } 1322 1323 static void 1324 dnode_buf_evict_async(void *dbu) 1325 { 1326 dnode_children_t *dnc = dbu; 1327 1328 DNODE_STAT_BUMP(dnode_buf_evict); 1329 1330 for (int i = 0; i < dnc->dnc_count; i++) { 1331 dnode_handle_t *dnh = &dnc->dnc_children[i]; 1332 dnode_t *dn; 1333 1334 /* 1335 * The dnode handle lock guards against the dnode moving to 1336 * another valid address, so there is no need here to guard 1337 * against changes to or from NULL. 1338 */ 1339 if (!DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1340 zrl_destroy(&dnh->dnh_zrlock); 1341 dnh->dnh_dnode = DN_SLOT_UNINIT; 1342 continue; 1343 } 1344 1345 zrl_add(&dnh->dnh_zrlock); 1346 dn = dnh->dnh_dnode; 1347 /* 1348 * If there are holds on this dnode, then there should 1349 * be holds on the dnode's containing dbuf as well; thus 1350 * it wouldn't be eligible for eviction and this function 1351 * would not have been called. 1352 */ 1353 ASSERT(zfs_refcount_is_zero(&dn->dn_holds)); 1354 ASSERT(zfs_refcount_is_zero(&dn->dn_tx_holds)); 1355 1356 dnode_destroy(dn); /* implicit zrl_remove() for first slot */ 1357 zrl_destroy(&dnh->dnh_zrlock); 1358 dnh->dnh_dnode = DN_SLOT_UNINIT; 1359 } 1360 kmem_free(dnc, sizeof (dnode_children_t) + 1361 dnc->dnc_count * sizeof (dnode_handle_t)); 1362 } 1363 1364 /* 1365 * When the DNODE_MUST_BE_FREE flag is set, the "slots" parameter is used 1366 * to ensure the hole at the specified object offset is large enough to 1367 * hold the dnode being created. The slots parameter is also used to ensure 1368 * a dnode does not span multiple dnode blocks. In both of these cases, if 1369 * a failure occurs, ENOSPC is returned. Keep in mind, these failure cases 1370 * are only possible when using DNODE_MUST_BE_FREE. 1371 * 1372 * If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0. 1373 * dnode_hold_impl() will check if the requested dnode is already consumed 1374 * as an extra dnode slot by an large dnode, in which case it returns 1375 * ENOENT. 1376 * 1377 * If the DNODE_DRY_RUN flag is set, we don't actually hold the dnode, just 1378 * return whether the hold would succeed or not. tag and dnp should set to 1379 * NULL in this case. 1380 * 1381 * errors: 1382 * EINVAL - Invalid object number or flags. 1383 * ENOSPC - Hole too small to fulfill "slots" request (DNODE_MUST_BE_FREE) 1384 * EEXIST - Refers to an allocated dnode (DNODE_MUST_BE_FREE) 1385 * - Refers to a freeing dnode (DNODE_MUST_BE_FREE) 1386 * - Refers to an interior dnode slot (DNODE_MUST_BE_ALLOCATED) 1387 * ENOENT - The requested dnode is not allocated (DNODE_MUST_BE_ALLOCATED) 1388 * - The requested dnode is being freed (DNODE_MUST_BE_ALLOCATED) 1389 * EIO - I/O error when reading the meta dnode dbuf. 1390 * 1391 * succeeds even for free dnodes. 1392 */ 1393 int 1394 dnode_hold_impl(objset_t *os, uint64_t object, int flag, int slots, 1395 const void *tag, dnode_t **dnp) 1396 { 1397 int epb, idx, err; 1398 int drop_struct_lock = FALSE; 1399 int type; 1400 uint64_t blk; 1401 dnode_t *mdn, *dn; 1402 dmu_buf_impl_t *db; 1403 dnode_children_t *dnc; 1404 dnode_phys_t *dn_block; 1405 dnode_handle_t *dnh; 1406 1407 ASSERT(!(flag & DNODE_MUST_BE_ALLOCATED) || (slots == 0)); 1408 ASSERT(!(flag & DNODE_MUST_BE_FREE) || (slots > 0)); 1409 IMPLY(flag & DNODE_DRY_RUN, (tag == NULL) && (dnp == NULL)); 1410 1411 /* 1412 * If you are holding the spa config lock as writer, you shouldn't 1413 * be asking the DMU to do *anything* unless it's the root pool 1414 * which may require us to read from the root filesystem while 1415 * holding some (not all) of the locks as writer. 1416 */ 1417 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1418 (spa_is_root(os->os_spa) && 1419 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1420 1421 ASSERT((flag & DNODE_MUST_BE_ALLOCATED) || (flag & DNODE_MUST_BE_FREE)); 1422 1423 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT || 1424 object == DMU_PROJECTUSED_OBJECT) { 1425 if (object == DMU_USERUSED_OBJECT) 1426 dn = DMU_USERUSED_DNODE(os); 1427 else if (object == DMU_GROUPUSED_OBJECT) 1428 dn = DMU_GROUPUSED_DNODE(os); 1429 else 1430 dn = DMU_PROJECTUSED_DNODE(os); 1431 if (dn == NULL) 1432 return (SET_ERROR(ENOENT)); 1433 type = dn->dn_type; 1434 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1435 return (SET_ERROR(ENOENT)); 1436 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1437 return (SET_ERROR(EEXIST)); 1438 DNODE_VERIFY(dn); 1439 /* Don't actually hold if dry run, just return 0 */ 1440 if (!(flag & DNODE_DRY_RUN)) { 1441 (void) zfs_refcount_add(&dn->dn_holds, tag); 1442 *dnp = dn; 1443 } 1444 return (0); 1445 } 1446 1447 if (object == 0 || object >= DN_MAX_OBJECT) 1448 return (SET_ERROR(EINVAL)); 1449 1450 mdn = DMU_META_DNODE(os); 1451 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1452 1453 DNODE_VERIFY(mdn); 1454 1455 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1456 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1457 drop_struct_lock = TRUE; 1458 } 1459 1460 blk = dbuf_whichblock(mdn, 0, object * sizeof (dnode_phys_t)); 1461 db = dbuf_hold(mdn, blk, FTAG); 1462 if (drop_struct_lock) 1463 rw_exit(&mdn->dn_struct_rwlock); 1464 if (db == NULL) { 1465 DNODE_STAT_BUMP(dnode_hold_dbuf_hold); 1466 return (SET_ERROR(EIO)); 1467 } 1468 1469 /* 1470 * We do not need to decrypt to read the dnode so it doesn't matter 1471 * if we get the encrypted or decrypted version. 1472 */ 1473 err = dbuf_read(db, NULL, DB_RF_CANFAIL | 1474 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH); 1475 if (err) { 1476 DNODE_STAT_BUMP(dnode_hold_dbuf_read); 1477 dbuf_rele(db, FTAG); 1478 return (err); 1479 } 1480 1481 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1482 epb = db->db.db_size >> DNODE_SHIFT; 1483 1484 idx = object & (epb - 1); 1485 dn_block = (dnode_phys_t *)db->db.db_data; 1486 1487 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1488 dnc = dmu_buf_get_user(&db->db); 1489 dnh = NULL; 1490 if (dnc == NULL) { 1491 dnode_children_t *winner; 1492 int skip = 0; 1493 1494 dnc = kmem_zalloc(sizeof (dnode_children_t) + 1495 epb * sizeof (dnode_handle_t), KM_SLEEP); 1496 dnc->dnc_count = epb; 1497 dnh = &dnc->dnc_children[0]; 1498 1499 /* Initialize dnode slot status from dnode_phys_t */ 1500 for (int i = 0; i < epb; i++) { 1501 zrl_init(&dnh[i].dnh_zrlock); 1502 1503 if (skip) { 1504 skip--; 1505 continue; 1506 } 1507 1508 if (dn_block[i].dn_type != DMU_OT_NONE) { 1509 int interior = dn_block[i].dn_extra_slots; 1510 1511 dnode_set_slots(dnc, i, 1, DN_SLOT_ALLOCATED); 1512 dnode_set_slots(dnc, i + 1, interior, 1513 DN_SLOT_INTERIOR); 1514 skip = interior; 1515 } else { 1516 dnh[i].dnh_dnode = DN_SLOT_FREE; 1517 skip = 0; 1518 } 1519 } 1520 1521 dmu_buf_init_user(&dnc->dnc_dbu, NULL, 1522 dnode_buf_evict_async, NULL); 1523 winner = dmu_buf_set_user(&db->db, &dnc->dnc_dbu); 1524 if (winner != NULL) { 1525 1526 for (int i = 0; i < epb; i++) 1527 zrl_destroy(&dnh[i].dnh_zrlock); 1528 1529 kmem_free(dnc, sizeof (dnode_children_t) + 1530 epb * sizeof (dnode_handle_t)); 1531 dnc = winner; 1532 } 1533 } 1534 1535 ASSERT(dnc->dnc_count == epb); 1536 1537 if (flag & DNODE_MUST_BE_ALLOCATED) { 1538 slots = 1; 1539 1540 dnode_slots_hold(dnc, idx, slots); 1541 dnh = &dnc->dnc_children[idx]; 1542 1543 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1544 dn = dnh->dnh_dnode; 1545 } else if (dnh->dnh_dnode == DN_SLOT_INTERIOR) { 1546 DNODE_STAT_BUMP(dnode_hold_alloc_interior); 1547 dnode_slots_rele(dnc, idx, slots); 1548 dbuf_rele(db, FTAG); 1549 return (SET_ERROR(EEXIST)); 1550 } else if (dnh->dnh_dnode != DN_SLOT_ALLOCATED) { 1551 DNODE_STAT_BUMP(dnode_hold_alloc_misses); 1552 dnode_slots_rele(dnc, idx, slots); 1553 dbuf_rele(db, FTAG); 1554 return (SET_ERROR(ENOENT)); 1555 } else { 1556 dnode_slots_rele(dnc, idx, slots); 1557 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1558 DNODE_STAT_BUMP(dnode_hold_alloc_lock_retry); 1559 kpreempt(KPREEMPT_SYNC); 1560 } 1561 1562 /* 1563 * Someone else won the race and called dnode_create() 1564 * after we checked DN_SLOT_IS_PTR() above but before 1565 * we acquired the lock. 1566 */ 1567 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1568 DNODE_STAT_BUMP(dnode_hold_alloc_lock_misses); 1569 dn = dnh->dnh_dnode; 1570 } else { 1571 dn = dnode_create(os, dn_block + idx, db, 1572 object, dnh); 1573 dmu_buf_add_user_size(&db->db, 1574 sizeof (dnode_t)); 1575 } 1576 } 1577 1578 mutex_enter(&dn->dn_mtx); 1579 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg != 0) { 1580 DNODE_STAT_BUMP(dnode_hold_alloc_type_none); 1581 mutex_exit(&dn->dn_mtx); 1582 dnode_slots_rele(dnc, idx, slots); 1583 dbuf_rele(db, FTAG); 1584 return (SET_ERROR(ENOENT)); 1585 } 1586 1587 /* Don't actually hold if dry run, just return 0 */ 1588 if (flag & DNODE_DRY_RUN) { 1589 mutex_exit(&dn->dn_mtx); 1590 dnode_slots_rele(dnc, idx, slots); 1591 dbuf_rele(db, FTAG); 1592 return (0); 1593 } 1594 1595 DNODE_STAT_BUMP(dnode_hold_alloc_hits); 1596 } else if (flag & DNODE_MUST_BE_FREE) { 1597 1598 if (idx + slots - 1 >= DNODES_PER_BLOCK) { 1599 DNODE_STAT_BUMP(dnode_hold_free_overflow); 1600 dbuf_rele(db, FTAG); 1601 return (SET_ERROR(ENOSPC)); 1602 } 1603 1604 dnode_slots_hold(dnc, idx, slots); 1605 1606 if (!dnode_check_slots_free(dnc, idx, slots)) { 1607 DNODE_STAT_BUMP(dnode_hold_free_misses); 1608 dnode_slots_rele(dnc, idx, slots); 1609 dbuf_rele(db, FTAG); 1610 return (SET_ERROR(ENOSPC)); 1611 } 1612 1613 dnode_slots_rele(dnc, idx, slots); 1614 while (!dnode_slots_tryenter(dnc, idx, slots)) { 1615 DNODE_STAT_BUMP(dnode_hold_free_lock_retry); 1616 kpreempt(KPREEMPT_SYNC); 1617 } 1618 1619 if (!dnode_check_slots_free(dnc, idx, slots)) { 1620 DNODE_STAT_BUMP(dnode_hold_free_lock_misses); 1621 dnode_slots_rele(dnc, idx, slots); 1622 dbuf_rele(db, FTAG); 1623 return (SET_ERROR(ENOSPC)); 1624 } 1625 1626 /* 1627 * Allocated but otherwise free dnodes which would 1628 * be in the interior of a multi-slot dnodes need 1629 * to be freed. Single slot dnodes can be safely 1630 * re-purposed as a performance optimization. 1631 */ 1632 if (slots > 1) { 1633 uint_t reclaimed = 1634 dnode_reclaim_slots(dnc, idx + 1, slots - 1); 1635 if (reclaimed > 0) 1636 dmu_buf_sub_user_size(&db->db, 1637 reclaimed * sizeof (dnode_t)); 1638 } 1639 1640 dnh = &dnc->dnc_children[idx]; 1641 if (DN_SLOT_IS_PTR(dnh->dnh_dnode)) { 1642 dn = dnh->dnh_dnode; 1643 } else { 1644 dn = dnode_create(os, dn_block + idx, db, 1645 object, dnh); 1646 dmu_buf_add_user_size(&db->db, sizeof (dnode_t)); 1647 } 1648 1649 mutex_enter(&dn->dn_mtx); 1650 if (!zfs_refcount_is_zero(&dn->dn_holds) || dn->dn_free_txg) { 1651 DNODE_STAT_BUMP(dnode_hold_free_refcount); 1652 mutex_exit(&dn->dn_mtx); 1653 dnode_slots_rele(dnc, idx, slots); 1654 dbuf_rele(db, FTAG); 1655 return (SET_ERROR(EEXIST)); 1656 } 1657 1658 /* Don't actually hold if dry run, just return 0 */ 1659 if (flag & DNODE_DRY_RUN) { 1660 mutex_exit(&dn->dn_mtx); 1661 dnode_slots_rele(dnc, idx, slots); 1662 dbuf_rele(db, FTAG); 1663 return (0); 1664 } 1665 1666 dnode_set_slots(dnc, idx + 1, slots - 1, DN_SLOT_INTERIOR); 1667 DNODE_STAT_BUMP(dnode_hold_free_hits); 1668 } else { 1669 dbuf_rele(db, FTAG); 1670 return (SET_ERROR(EINVAL)); 1671 } 1672 1673 ASSERT0(dn->dn_free_txg); 1674 1675 if (zfs_refcount_add(&dn->dn_holds, tag) == 1) 1676 dbuf_add_ref(db, dnh); 1677 1678 mutex_exit(&dn->dn_mtx); 1679 1680 /* Now we can rely on the hold to prevent the dnode from moving. */ 1681 dnode_slots_rele(dnc, idx, slots); 1682 1683 DNODE_VERIFY(dn); 1684 ASSERT3P(dnp, !=, NULL); 1685 ASSERT3P(dn->dn_dbuf, ==, db); 1686 ASSERT3U(dn->dn_object, ==, object); 1687 dbuf_rele(db, FTAG); 1688 1689 *dnp = dn; 1690 return (0); 1691 } 1692 1693 /* 1694 * Return held dnode if the object is allocated, NULL if not. 1695 */ 1696 int 1697 dnode_hold(objset_t *os, uint64_t object, const void *tag, dnode_t **dnp) 1698 { 1699 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, 0, tag, 1700 dnp)); 1701 } 1702 1703 /* 1704 * Can only add a reference if there is already at least one 1705 * reference on the dnode. Returns FALSE if unable to add a 1706 * new reference. 1707 */ 1708 boolean_t 1709 dnode_add_ref(dnode_t *dn, const void *tag) 1710 { 1711 mutex_enter(&dn->dn_mtx); 1712 if (zfs_refcount_is_zero(&dn->dn_holds)) { 1713 mutex_exit(&dn->dn_mtx); 1714 return (FALSE); 1715 } 1716 VERIFY(1 < zfs_refcount_add(&dn->dn_holds, tag)); 1717 mutex_exit(&dn->dn_mtx); 1718 return (TRUE); 1719 } 1720 1721 void 1722 dnode_rele(dnode_t *dn, const void *tag) 1723 { 1724 mutex_enter(&dn->dn_mtx); 1725 dnode_rele_and_unlock(dn, tag, B_FALSE); 1726 } 1727 1728 void 1729 dnode_rele_and_unlock(dnode_t *dn, const void *tag, boolean_t evicting) 1730 { 1731 uint64_t refs; 1732 /* Get while the hold prevents the dnode from moving. */ 1733 dmu_buf_impl_t *db = dn->dn_dbuf; 1734 dnode_handle_t *dnh = dn->dn_handle; 1735 1736 refs = zfs_refcount_remove(&dn->dn_holds, tag); 1737 if (refs == 0) 1738 cv_broadcast(&dn->dn_nodnholds); 1739 mutex_exit(&dn->dn_mtx); 1740 /* dnode could get destroyed at this point, so don't use it anymore */ 1741 1742 /* 1743 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1744 * indirectly by dbuf_rele() while relying on the dnode handle to 1745 * prevent the dnode from moving, since releasing the last hold could 1746 * result in the dnode's parent dbuf evicting its dnode handles. For 1747 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1748 * other direct or indirect hold on the dnode must first drop the dnode 1749 * handle. 1750 */ 1751 #ifdef ZFS_DEBUG 1752 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread); 1753 #endif 1754 1755 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1756 if (refs == 0 && db != NULL) { 1757 /* 1758 * Another thread could add a hold to the dnode handle in 1759 * dnode_hold_impl() while holding the parent dbuf. Since the 1760 * hold on the parent dbuf prevents the handle from being 1761 * destroyed, the hold on the handle is OK. We can't yet assert 1762 * that the handle has zero references, but that will be 1763 * asserted anyway when the handle gets destroyed. 1764 */ 1765 mutex_enter(&db->db_mtx); 1766 dbuf_rele_and_unlock(db, dnh, evicting); 1767 } 1768 } 1769 1770 /* 1771 * Test whether we can create a dnode at the specified location. 1772 */ 1773 int 1774 dnode_try_claim(objset_t *os, uint64_t object, int slots) 1775 { 1776 return (dnode_hold_impl(os, object, DNODE_MUST_BE_FREE | DNODE_DRY_RUN, 1777 slots, NULL, NULL)); 1778 } 1779 1780 /* 1781 * Checks if the dnode contains any uncommitted dirty records. 1782 */ 1783 boolean_t 1784 dnode_is_dirty(dnode_t *dn) 1785 { 1786 mutex_enter(&dn->dn_mtx); 1787 1788 for (int i = 0; i < TXG_SIZE; i++) { 1789 if (multilist_link_active(&dn->dn_dirty_link[i])) { 1790 mutex_exit(&dn->dn_mtx); 1791 return (B_TRUE); 1792 } 1793 } 1794 1795 mutex_exit(&dn->dn_mtx); 1796 1797 return (B_FALSE); 1798 } 1799 1800 void 1801 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1802 { 1803 objset_t *os = dn->dn_objset; 1804 uint64_t txg = tx->tx_txg; 1805 1806 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1807 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1808 return; 1809 } 1810 1811 DNODE_VERIFY(dn); 1812 1813 #ifdef ZFS_DEBUG 1814 mutex_enter(&dn->dn_mtx); 1815 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1816 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1817 mutex_exit(&dn->dn_mtx); 1818 #endif 1819 1820 /* 1821 * Determine old uid/gid when necessary 1822 */ 1823 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1824 1825 multilist_t *dirtylist = &os->os_dirty_dnodes[txg & TXG_MASK]; 1826 multilist_sublist_t *mls = multilist_sublist_lock_obj(dirtylist, dn); 1827 1828 /* 1829 * If we are already marked dirty, we're done. 1830 */ 1831 if (multilist_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1832 multilist_sublist_unlock(mls); 1833 return; 1834 } 1835 1836 ASSERT(!zfs_refcount_is_zero(&dn->dn_holds) || 1837 !avl_is_empty(&dn->dn_dbufs)); 1838 ASSERT(dn->dn_datablksz != 0); 1839 ASSERT0(dn->dn_next_bonuslen[txg & TXG_MASK]); 1840 ASSERT0(dn->dn_next_blksz[txg & TXG_MASK]); 1841 ASSERT0(dn->dn_next_bonustype[txg & TXG_MASK]); 1842 1843 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1844 (u_longlong_t)dn->dn_object, (u_longlong_t)txg); 1845 1846 multilist_sublist_insert_head(mls, dn); 1847 1848 multilist_sublist_unlock(mls); 1849 1850 /* 1851 * The dnode maintains a hold on its containing dbuf as 1852 * long as there are holds on it. Each instantiated child 1853 * dbuf maintains a hold on the dnode. When the last child 1854 * drops its hold, the dnode will drop its hold on the 1855 * containing dbuf. We add a "dirty hold" here so that the 1856 * dnode will hang around after we finish processing its 1857 * children. 1858 */ 1859 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1860 1861 (void) dbuf_dirty(dn->dn_dbuf, tx); 1862 1863 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1864 } 1865 1866 void 1867 dnode_free(dnode_t *dn, dmu_tx_t *tx) 1868 { 1869 mutex_enter(&dn->dn_mtx); 1870 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1871 mutex_exit(&dn->dn_mtx); 1872 return; 1873 } 1874 dn->dn_free_txg = tx->tx_txg; 1875 mutex_exit(&dn->dn_mtx); 1876 1877 dnode_setdirty(dn, tx); 1878 } 1879 1880 /* 1881 * Try to change the block size for the indicated dnode. This can only 1882 * succeed if there are no blocks allocated or dirty beyond first block 1883 */ 1884 int 1885 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1886 { 1887 dmu_buf_impl_t *db; 1888 int err; 1889 1890 ASSERT3U(size, <=, spa_maxblocksize(dmu_objset_spa(dn->dn_objset))); 1891 if (size == 0) 1892 size = SPA_MINBLOCKSIZE; 1893 else 1894 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1895 1896 if (ibs == dn->dn_indblkshift) 1897 ibs = 0; 1898 1899 if (size == dn->dn_datablksz && ibs == 0) 1900 return (0); 1901 1902 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1903 1904 /* Check for any allocated blocks beyond the first */ 1905 if (dn->dn_maxblkid != 0) 1906 goto fail; 1907 1908 mutex_enter(&dn->dn_dbufs_mtx); 1909 for (db = avl_first(&dn->dn_dbufs); db != NULL; 1910 db = AVL_NEXT(&dn->dn_dbufs, db)) { 1911 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1912 db->db_blkid != DMU_SPILL_BLKID) { 1913 mutex_exit(&dn->dn_dbufs_mtx); 1914 goto fail; 1915 } 1916 } 1917 mutex_exit(&dn->dn_dbufs_mtx); 1918 1919 if (ibs && dn->dn_nlevels != 1) 1920 goto fail; 1921 1922 dnode_setdirty(dn, tx); 1923 if (size != dn->dn_datablksz) { 1924 /* resize the old block */ 1925 err = dbuf_hold_impl(dn, 0, 0, TRUE, FALSE, FTAG, &db); 1926 if (err == 0) { 1927 dbuf_new_size(db, size, tx); 1928 } else if (err != ENOENT) { 1929 goto fail; 1930 } 1931 1932 dnode_setdblksz(dn, size); 1933 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = size; 1934 if (db) 1935 dbuf_rele(db, FTAG); 1936 } 1937 if (ibs) { 1938 dn->dn_indblkshift = ibs; 1939 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 1940 } 1941 1942 rw_exit(&dn->dn_struct_rwlock); 1943 return (0); 1944 1945 fail: 1946 rw_exit(&dn->dn_struct_rwlock); 1947 return (SET_ERROR(ENOTSUP)); 1948 } 1949 1950 static void 1951 dnode_set_nlevels_impl(dnode_t *dn, int new_nlevels, dmu_tx_t *tx) 1952 { 1953 uint64_t txgoff = tx->tx_txg & TXG_MASK; 1954 int old_nlevels = dn->dn_nlevels; 1955 dmu_buf_impl_t *db; 1956 list_t *list; 1957 dbuf_dirty_record_t *new, *dr, *dr_next; 1958 1959 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 1960 1961 ASSERT3U(new_nlevels, >, dn->dn_nlevels); 1962 dn->dn_nlevels = new_nlevels; 1963 1964 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 1965 dn->dn_next_nlevels[txgoff] = new_nlevels; 1966 1967 /* dirty the left indirects */ 1968 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 1969 ASSERT(db != NULL); 1970 new = dbuf_dirty(db, tx); 1971 dbuf_rele(db, FTAG); 1972 1973 /* transfer the dirty records to the new indirect */ 1974 mutex_enter(&dn->dn_mtx); 1975 mutex_enter(&new->dt.di.dr_mtx); 1976 list = &dn->dn_dirty_records[txgoff]; 1977 for (dr = list_head(list); dr; dr = dr_next) { 1978 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 1979 1980 IMPLY(dr->dr_dbuf == NULL, old_nlevels == 1); 1981 if (dr->dr_dbuf == NULL || 1982 (dr->dr_dbuf->db_level == old_nlevels - 1 && 1983 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 1984 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID)) { 1985 list_remove(&dn->dn_dirty_records[txgoff], dr); 1986 list_insert_tail(&new->dt.di.dr_children, dr); 1987 dr->dr_parent = new; 1988 } 1989 } 1990 mutex_exit(&new->dt.di.dr_mtx); 1991 mutex_exit(&dn->dn_mtx); 1992 } 1993 1994 int 1995 dnode_set_nlevels(dnode_t *dn, int nlevels, dmu_tx_t *tx) 1996 { 1997 int ret = 0; 1998 1999 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2000 2001 if (dn->dn_nlevels == nlevels) { 2002 ret = 0; 2003 goto out; 2004 } else if (nlevels < dn->dn_nlevels) { 2005 ret = SET_ERROR(EINVAL); 2006 goto out; 2007 } 2008 2009 dnode_set_nlevels_impl(dn, nlevels, tx); 2010 2011 out: 2012 rw_exit(&dn->dn_struct_rwlock); 2013 return (ret); 2014 } 2015 2016 /* read-holding callers must not rely on the lock being continuously held */ 2017 void 2018 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read, 2019 boolean_t force) 2020 { 2021 int epbs, new_nlevels; 2022 uint64_t sz; 2023 2024 ASSERT(blkid != DMU_BONUS_BLKID); 2025 2026 ASSERT(have_read ? 2027 RW_READ_HELD(&dn->dn_struct_rwlock) : 2028 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 2029 2030 /* 2031 * if we have a read-lock, check to see if we need to do any work 2032 * before upgrading to a write-lock. 2033 */ 2034 if (have_read) { 2035 if (blkid <= dn->dn_maxblkid) 2036 return; 2037 2038 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 2039 rw_exit(&dn->dn_struct_rwlock); 2040 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2041 } 2042 } 2043 2044 /* 2045 * Raw sends (indicated by the force flag) require that we take the 2046 * given blkid even if the value is lower than the current value. 2047 */ 2048 if (!force && blkid <= dn->dn_maxblkid) 2049 goto out; 2050 2051 /* 2052 * We use the (otherwise unused) top bit of dn_next_maxblkid[txgoff] 2053 * to indicate that this field is set. This allows us to set the 2054 * maxblkid to 0 on an existing object in dnode_sync(). 2055 */ 2056 dn->dn_maxblkid = blkid; 2057 dn->dn_next_maxblkid[tx->tx_txg & TXG_MASK] = 2058 blkid | DMU_NEXT_MAXBLKID_SET; 2059 2060 /* 2061 * Compute the number of levels necessary to support the new maxblkid. 2062 * Raw sends will ensure nlevels is set correctly for us. 2063 */ 2064 new_nlevels = 1; 2065 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2066 for (sz = dn->dn_nblkptr; 2067 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 2068 new_nlevels++; 2069 2070 ASSERT3U(new_nlevels, <=, DN_MAX_LEVELS); 2071 2072 if (!force) { 2073 if (new_nlevels > dn->dn_nlevels) 2074 dnode_set_nlevels_impl(dn, new_nlevels, tx); 2075 } else { 2076 ASSERT3U(dn->dn_nlevels, >=, new_nlevels); 2077 } 2078 2079 out: 2080 if (have_read) 2081 rw_downgrade(&dn->dn_struct_rwlock); 2082 } 2083 2084 static void 2085 dnode_dirty_l1(dnode_t *dn, uint64_t l1blkid, dmu_tx_t *tx) 2086 { 2087 dmu_buf_impl_t *db = dbuf_hold_level(dn, 1, l1blkid, FTAG); 2088 if (db != NULL) { 2089 dmu_buf_will_dirty(&db->db, tx); 2090 dbuf_rele(db, FTAG); 2091 } 2092 } 2093 2094 /* 2095 * Dirty all the in-core level-1 dbufs in the range specified by start_blkid 2096 * and end_blkid. 2097 */ 2098 static void 2099 dnode_dirty_l1range(dnode_t *dn, uint64_t start_blkid, uint64_t end_blkid, 2100 dmu_tx_t *tx) 2101 { 2102 dmu_buf_impl_t *db_search; 2103 dmu_buf_impl_t *db; 2104 avl_index_t where; 2105 2106 db_search = kmem_zalloc(sizeof (dmu_buf_impl_t), KM_SLEEP); 2107 2108 mutex_enter(&dn->dn_dbufs_mtx); 2109 2110 db_search->db_level = 1; 2111 db_search->db_blkid = start_blkid + 1; 2112 db_search->db_state = DB_SEARCH; 2113 for (;;) { 2114 2115 db = avl_find(&dn->dn_dbufs, db_search, &where); 2116 if (db == NULL) 2117 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2118 2119 if (db == NULL || db->db_level != 1 || 2120 db->db_blkid >= end_blkid) { 2121 break; 2122 } 2123 2124 /* 2125 * Setup the next blkid we want to search for. 2126 */ 2127 db_search->db_blkid = db->db_blkid + 1; 2128 ASSERT3U(db->db_blkid, >=, start_blkid); 2129 2130 /* 2131 * If the dbuf transitions to DB_EVICTING while we're trying 2132 * to dirty it, then we will be unable to discover it in 2133 * the dbuf hash table. This will result in a call to 2134 * dbuf_create() which needs to acquire the dn_dbufs_mtx 2135 * lock. To avoid a deadlock, we drop the lock before 2136 * dirtying the level-1 dbuf. 2137 */ 2138 mutex_exit(&dn->dn_dbufs_mtx); 2139 dnode_dirty_l1(dn, db->db_blkid, tx); 2140 mutex_enter(&dn->dn_dbufs_mtx); 2141 } 2142 2143 #ifdef ZFS_DEBUG 2144 /* 2145 * Walk all the in-core level-1 dbufs and verify they have been dirtied. 2146 */ 2147 db_search->db_level = 1; 2148 db_search->db_blkid = start_blkid + 1; 2149 db_search->db_state = DB_SEARCH; 2150 db = avl_find(&dn->dn_dbufs, db_search, &where); 2151 if (db == NULL) 2152 db = avl_nearest(&dn->dn_dbufs, where, AVL_AFTER); 2153 for (; db != NULL; db = AVL_NEXT(&dn->dn_dbufs, db)) { 2154 if (db->db_level != 1 || db->db_blkid >= end_blkid) 2155 break; 2156 if (db->db_state != DB_EVICTING) 2157 ASSERT(db->db_dirtycnt > 0); 2158 } 2159 #endif 2160 kmem_free(db_search, sizeof (dmu_buf_impl_t)); 2161 mutex_exit(&dn->dn_dbufs_mtx); 2162 } 2163 2164 void 2165 dnode_set_dirtyctx(dnode_t *dn, dmu_tx_t *tx, const void *tag) 2166 { 2167 /* 2168 * Don't set dirtyctx to SYNC if we're just modifying this as we 2169 * initialize the objset. 2170 */ 2171 if (dn->dn_dirtyctx == DN_UNDIRTIED) { 2172 dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset; 2173 2174 if (ds != NULL) { 2175 rrw_enter(&ds->ds_bp_rwlock, RW_READER, tag); 2176 } 2177 if (!BP_IS_HOLE(dn->dn_objset->os_rootbp)) { 2178 if (dmu_tx_is_syncing(tx)) 2179 dn->dn_dirtyctx = DN_DIRTY_SYNC; 2180 else 2181 dn->dn_dirtyctx = DN_DIRTY_OPEN; 2182 dn->dn_dirtyctx_firstset = tag; 2183 } 2184 if (ds != NULL) { 2185 rrw_exit(&ds->ds_bp_rwlock, tag); 2186 } 2187 } 2188 } 2189 2190 static void 2191 dnode_partial_zero(dnode_t *dn, uint64_t off, uint64_t blkoff, uint64_t len, 2192 dmu_tx_t *tx) 2193 { 2194 dmu_buf_impl_t *db; 2195 int res; 2196 2197 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2198 res = dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, 0, off), TRUE, FALSE, 2199 FTAG, &db); 2200 rw_exit(&dn->dn_struct_rwlock); 2201 if (res == 0) { 2202 db_lock_type_t dblt; 2203 boolean_t dirty; 2204 2205 dblt = dmu_buf_lock_parent(db, RW_READER, FTAG); 2206 /* don't dirty if not on disk and not dirty */ 2207 dirty = !list_is_empty(&db->db_dirty_records) || 2208 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr)); 2209 dmu_buf_unlock_parent(db, dblt, FTAG); 2210 if (dirty) { 2211 caddr_t data; 2212 2213 dmu_buf_will_dirty(&db->db, tx); 2214 data = db->db.db_data; 2215 memset(data + blkoff, 0, len); 2216 } 2217 dbuf_rele(db, FTAG); 2218 } 2219 } 2220 2221 void 2222 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 2223 { 2224 uint64_t blkoff, blkid, nblks; 2225 int blksz, blkshift, head, tail; 2226 int trunc = FALSE; 2227 int epbs; 2228 2229 blksz = dn->dn_datablksz; 2230 blkshift = dn->dn_datablkshift; 2231 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 2232 2233 if (len == DMU_OBJECT_END) { 2234 len = UINT64_MAX - off; 2235 trunc = TRUE; 2236 } 2237 2238 /* 2239 * First, block align the region to free: 2240 */ 2241 if (ISP2(blksz)) { 2242 head = P2NPHASE(off, blksz); 2243 blkoff = P2PHASE(off, blksz); 2244 if ((off >> blkshift) > dn->dn_maxblkid) 2245 return; 2246 } else { 2247 ASSERT(dn->dn_maxblkid == 0); 2248 if (off == 0 && len >= blksz) { 2249 /* 2250 * Freeing the whole block; fast-track this request. 2251 */ 2252 blkid = 0; 2253 nblks = 1; 2254 if (dn->dn_nlevels > 1) { 2255 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2256 dnode_dirty_l1(dn, 0, tx); 2257 rw_exit(&dn->dn_struct_rwlock); 2258 } 2259 goto done; 2260 } else if (off >= blksz) { 2261 /* Freeing past end-of-data */ 2262 return; 2263 } else { 2264 /* Freeing part of the block. */ 2265 head = blksz - off; 2266 ASSERT3U(head, >, 0); 2267 } 2268 blkoff = off; 2269 } 2270 /* zero out any partial block data at the start of the range */ 2271 if (head) { 2272 ASSERT3U(blkoff + head, ==, blksz); 2273 if (len < head) 2274 head = len; 2275 dnode_partial_zero(dn, off, blkoff, head, tx); 2276 off += head; 2277 len -= head; 2278 } 2279 2280 /* If the range was less than one block, we're done */ 2281 if (len == 0) 2282 return; 2283 2284 /* If the remaining range is past end of file, we're done */ 2285 if ((off >> blkshift) > dn->dn_maxblkid) 2286 return; 2287 2288 ASSERT(ISP2(blksz)); 2289 if (trunc) 2290 tail = 0; 2291 else 2292 tail = P2PHASE(len, blksz); 2293 2294 ASSERT0(P2PHASE(off, blksz)); 2295 /* zero out any partial block data at the end of the range */ 2296 if (tail) { 2297 if (len < tail) 2298 tail = len; 2299 dnode_partial_zero(dn, off + len, 0, tail, tx); 2300 len -= tail; 2301 } 2302 2303 /* If the range did not include a full block, we are done */ 2304 if (len == 0) 2305 return; 2306 2307 ASSERT(IS_P2ALIGNED(off, blksz)); 2308 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 2309 blkid = off >> blkshift; 2310 nblks = len >> blkshift; 2311 if (trunc) 2312 nblks += 1; 2313 2314 /* 2315 * Dirty all the indirect blocks in this range. Note that only 2316 * the first and last indirect blocks can actually be written 2317 * (if they were partially freed) -- they must be dirtied, even if 2318 * they do not exist on disk yet. The interior blocks will 2319 * be freed by free_children(), so they will not actually be written. 2320 * Even though these interior blocks will not be written, we 2321 * dirty them for two reasons: 2322 * 2323 * - It ensures that the indirect blocks remain in memory until 2324 * syncing context. (They have already been prefetched by 2325 * dmu_tx_hold_free(), so we don't have to worry about reading 2326 * them serially here.) 2327 * 2328 * - The dirty space accounting will put pressure on the txg sync 2329 * mechanism to begin syncing, and to delay transactions if there 2330 * is a large amount of freeing. Even though these indirect 2331 * blocks will not be written, we could need to write the same 2332 * amount of space if we copy the freed BPs into deadlists. 2333 */ 2334 if (dn->dn_nlevels > 1) { 2335 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 2336 uint64_t first, last; 2337 2338 first = blkid >> epbs; 2339 dnode_dirty_l1(dn, first, tx); 2340 if (trunc) 2341 last = dn->dn_maxblkid >> epbs; 2342 else 2343 last = (blkid + nblks - 1) >> epbs; 2344 if (last != first) 2345 dnode_dirty_l1(dn, last, tx); 2346 2347 dnode_dirty_l1range(dn, first, last, tx); 2348 2349 int shift = dn->dn_datablkshift + dn->dn_indblkshift - 2350 SPA_BLKPTRSHIFT; 2351 for (uint64_t i = first + 1; i < last; i++) { 2352 /* 2353 * Set i to the blockid of the next non-hole 2354 * level-1 indirect block at or after i. Note 2355 * that dnode_next_offset() operates in terms of 2356 * level-0-equivalent bytes. 2357 */ 2358 uint64_t ibyte = i << shift; 2359 int err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, 2360 &ibyte, 2, 1, 0); 2361 i = ibyte >> shift; 2362 if (i >= last) 2363 break; 2364 2365 /* 2366 * Normally we should not see an error, either 2367 * from dnode_next_offset() or dbuf_hold_level() 2368 * (except for ESRCH from dnode_next_offset). 2369 * If there is an i/o error, then when we read 2370 * this block in syncing context, it will use 2371 * ZIO_FLAG_MUSTSUCCEED, and thus hang/panic according 2372 * to the "failmode" property. dnode_next_offset() 2373 * doesn't have a flag to indicate MUSTSUCCEED. 2374 */ 2375 if (err != 0) 2376 break; 2377 2378 dnode_dirty_l1(dn, i, tx); 2379 } 2380 rw_exit(&dn->dn_struct_rwlock); 2381 } 2382 2383 done: 2384 /* 2385 * Add this range to the dnode range list. 2386 * We will finish up this free operation in the syncing phase. 2387 */ 2388 mutex_enter(&dn->dn_mtx); 2389 { 2390 int txgoff = tx->tx_txg & TXG_MASK; 2391 if (dn->dn_free_ranges[txgoff] == NULL) { 2392 dn->dn_free_ranges[txgoff] = range_tree_create(NULL, 2393 RANGE_SEG64, NULL, 0, 0); 2394 } 2395 range_tree_clear(dn->dn_free_ranges[txgoff], blkid, nblks); 2396 range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks); 2397 } 2398 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 2399 (u_longlong_t)blkid, (u_longlong_t)nblks, 2400 (u_longlong_t)tx->tx_txg); 2401 mutex_exit(&dn->dn_mtx); 2402 2403 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 2404 dnode_setdirty(dn, tx); 2405 } 2406 2407 static boolean_t 2408 dnode_spill_freed(dnode_t *dn) 2409 { 2410 int i; 2411 2412 mutex_enter(&dn->dn_mtx); 2413 for (i = 0; i < TXG_SIZE; i++) { 2414 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 2415 break; 2416 } 2417 mutex_exit(&dn->dn_mtx); 2418 return (i < TXG_SIZE); 2419 } 2420 2421 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 2422 uint64_t 2423 dnode_block_freed(dnode_t *dn, uint64_t blkid) 2424 { 2425 int i; 2426 2427 if (blkid == DMU_BONUS_BLKID) 2428 return (FALSE); 2429 2430 if (dn->dn_free_txg) 2431 return (TRUE); 2432 2433 if (blkid == DMU_SPILL_BLKID) 2434 return (dnode_spill_freed(dn)); 2435 2436 mutex_enter(&dn->dn_mtx); 2437 for (i = 0; i < TXG_SIZE; i++) { 2438 if (dn->dn_free_ranges[i] != NULL && 2439 range_tree_contains(dn->dn_free_ranges[i], blkid, 1)) 2440 break; 2441 } 2442 mutex_exit(&dn->dn_mtx); 2443 return (i < TXG_SIZE); 2444 } 2445 2446 /* call from syncing context when we actually write/free space for this dnode */ 2447 void 2448 dnode_diduse_space(dnode_t *dn, int64_t delta) 2449 { 2450 uint64_t space; 2451 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 2452 dn, dn->dn_phys, 2453 (u_longlong_t)dn->dn_phys->dn_used, 2454 (longlong_t)delta); 2455 2456 mutex_enter(&dn->dn_mtx); 2457 space = DN_USED_BYTES(dn->dn_phys); 2458 if (delta > 0) { 2459 ASSERT3U(space + delta, >=, space); /* no overflow */ 2460 } else { 2461 ASSERT3U(space, >=, -delta); /* no underflow */ 2462 } 2463 space += delta; 2464 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 2465 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 2466 ASSERT0(P2PHASE(space, 1<<DEV_BSHIFT)); 2467 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 2468 } else { 2469 dn->dn_phys->dn_used = space; 2470 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 2471 } 2472 mutex_exit(&dn->dn_mtx); 2473 } 2474 2475 /* 2476 * Scans a block at the indicated "level" looking for a hole or data, 2477 * depending on 'flags'. 2478 * 2479 * If level > 0, then we are scanning an indirect block looking at its 2480 * pointers. If level == 0, then we are looking at a block of dnodes. 2481 * 2482 * If we don't find what we are looking for in the block, we return ESRCH. 2483 * Otherwise, return with *offset pointing to the beginning (if searching 2484 * forwards) or end (if searching backwards) of the range covered by the 2485 * block pointer we matched on (or dnode). 2486 * 2487 * The basic search algorithm used below by dnode_next_offset() is to 2488 * use this function to search up the block tree (widen the search) until 2489 * we find something (i.e., we don't return ESRCH) and then search back 2490 * down the tree (narrow the search) until we reach our original search 2491 * level. 2492 */ 2493 static int 2494 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 2495 int lvl, uint64_t blkfill, uint64_t txg) 2496 { 2497 dmu_buf_impl_t *db = NULL; 2498 void *data = NULL; 2499 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 2500 uint64_t epb = 1ULL << epbs; 2501 uint64_t minfill, maxfill; 2502 boolean_t hole; 2503 int i, inc, error, span; 2504 2505 ASSERT(RW_LOCK_HELD(&dn->dn_struct_rwlock)); 2506 2507 hole = ((flags & DNODE_FIND_HOLE) != 0); 2508 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 2509 ASSERT(txg == 0 || !hole); 2510 2511 if (lvl == dn->dn_phys->dn_nlevels) { 2512 error = 0; 2513 epb = dn->dn_phys->dn_nblkptr; 2514 data = dn->dn_phys->dn_blkptr; 2515 } else { 2516 uint64_t blkid = dbuf_whichblock(dn, lvl, *offset); 2517 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FALSE, FTAG, &db); 2518 if (error) { 2519 if (error != ENOENT) 2520 return (error); 2521 if (hole) 2522 return (0); 2523 /* 2524 * This can only happen when we are searching up 2525 * the block tree for data. We don't really need to 2526 * adjust the offset, as we will just end up looking 2527 * at the pointer to this block in its parent, and its 2528 * going to be unallocated, so we will skip over it. 2529 */ 2530 return (SET_ERROR(ESRCH)); 2531 } 2532 error = dbuf_read(db, NULL, 2533 DB_RF_CANFAIL | DB_RF_HAVESTRUCT | 2534 DB_RF_NO_DECRYPT | DB_RF_NOPREFETCH); 2535 if (error) { 2536 dbuf_rele(db, FTAG); 2537 return (error); 2538 } 2539 data = db->db.db_data; 2540 rw_enter(&db->db_rwlock, RW_READER); 2541 } 2542 2543 if (db != NULL && txg != 0 && (db->db_blkptr == NULL || 2544 db->db_blkptr->blk_birth <= txg || 2545 BP_IS_HOLE(db->db_blkptr))) { 2546 /* 2547 * This can only happen when we are searching up the tree 2548 * and these conditions mean that we need to keep climbing. 2549 */ 2550 error = SET_ERROR(ESRCH); 2551 } else if (lvl == 0) { 2552 dnode_phys_t *dnp = data; 2553 2554 ASSERT(dn->dn_type == DMU_OT_DNODE); 2555 ASSERT(!(flags & DNODE_FIND_BACKWARDS)); 2556 2557 for (i = (*offset >> DNODE_SHIFT) & (blkfill - 1); 2558 i < blkfill; i += dnp[i].dn_extra_slots + 1) { 2559 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 2560 break; 2561 } 2562 2563 if (i == blkfill) 2564 error = SET_ERROR(ESRCH); 2565 2566 *offset = (*offset & ~(DNODE_BLOCK_SIZE - 1)) + 2567 (i << DNODE_SHIFT); 2568 } else { 2569 blkptr_t *bp = data; 2570 uint64_t start = *offset; 2571 span = (lvl - 1) * epbs + dn->dn_datablkshift; 2572 minfill = 0; 2573 maxfill = blkfill << ((lvl - 1) * epbs); 2574 2575 if (hole) 2576 maxfill--; 2577 else 2578 minfill++; 2579 2580 if (span >= 8 * sizeof (*offset)) { 2581 /* This only happens on the highest indirection level */ 2582 ASSERT3U((lvl - 1), ==, dn->dn_phys->dn_nlevels - 1); 2583 *offset = 0; 2584 } else { 2585 *offset = *offset >> span; 2586 } 2587 2588 for (i = BF64_GET(*offset, 0, epbs); 2589 i >= 0 && i < epb; i += inc) { 2590 if (BP_GET_FILL(&bp[i]) >= minfill && 2591 BP_GET_FILL(&bp[i]) <= maxfill && 2592 (hole || bp[i].blk_birth > txg)) 2593 break; 2594 if (inc > 0 || *offset > 0) 2595 *offset += inc; 2596 } 2597 2598 if (span >= 8 * sizeof (*offset)) { 2599 *offset = start; 2600 } else { 2601 *offset = *offset << span; 2602 } 2603 2604 if (inc < 0) { 2605 /* traversing backwards; position offset at the end */ 2606 if (span < 8 * sizeof (*offset)) 2607 *offset = MIN(*offset + (1ULL << span) - 1, 2608 start); 2609 } else if (*offset < start) { 2610 *offset = start; 2611 } 2612 if (i < 0 || i >= epb) 2613 error = SET_ERROR(ESRCH); 2614 } 2615 2616 if (db != NULL) { 2617 rw_exit(&db->db_rwlock); 2618 dbuf_rele(db, FTAG); 2619 } 2620 2621 return (error); 2622 } 2623 2624 /* 2625 * Find the next hole, data, or sparse region at or after *offset. 2626 * The value 'blkfill' tells us how many items we expect to find 2627 * in an L0 data block; this value is 1 for normal objects, 2628 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 2629 * DNODES_PER_BLOCK when searching for sparse regions thereof. 2630 * 2631 * Examples: 2632 * 2633 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 2634 * Finds the next/previous hole/data in a file. 2635 * Used in dmu_offset_next(). 2636 * 2637 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 2638 * Finds the next free/allocated dnode an objset's meta-dnode. 2639 * Only finds objects that have new contents since txg (ie. 2640 * bonus buffer changes and content removal are ignored). 2641 * Used in dmu_object_next(). 2642 * 2643 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 2644 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 2645 * Used in dmu_object_alloc(). 2646 */ 2647 int 2648 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 2649 int minlvl, uint64_t blkfill, uint64_t txg) 2650 { 2651 uint64_t initial_offset = *offset; 2652 int lvl, maxlvl; 2653 int error = 0; 2654 2655 if (!(flags & DNODE_FIND_HAVELOCK)) 2656 rw_enter(&dn->dn_struct_rwlock, RW_READER); 2657 2658 if (dn->dn_phys->dn_nlevels == 0) { 2659 error = SET_ERROR(ESRCH); 2660 goto out; 2661 } 2662 2663 if (dn->dn_datablkshift == 0) { 2664 if (*offset < dn->dn_datablksz) { 2665 if (flags & DNODE_FIND_HOLE) 2666 *offset = dn->dn_datablksz; 2667 } else { 2668 error = SET_ERROR(ESRCH); 2669 } 2670 goto out; 2671 } 2672 2673 maxlvl = dn->dn_phys->dn_nlevels; 2674 2675 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 2676 error = dnode_next_offset_level(dn, 2677 flags, offset, lvl, blkfill, txg); 2678 if (error != ESRCH) 2679 break; 2680 } 2681 2682 while (error == 0 && --lvl >= minlvl) { 2683 error = dnode_next_offset_level(dn, 2684 flags, offset, lvl, blkfill, txg); 2685 } 2686 2687 /* 2688 * There's always a "virtual hole" at the end of the object, even 2689 * if all BP's which physically exist are non-holes. 2690 */ 2691 if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 && 2692 minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) { 2693 error = 0; 2694 } 2695 2696 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 2697 initial_offset < *offset : initial_offset > *offset)) 2698 error = SET_ERROR(ESRCH); 2699 out: 2700 if (!(flags & DNODE_FIND_HAVELOCK)) 2701 rw_exit(&dn->dn_struct_rwlock); 2702 2703 return (error); 2704 } 2705 2706 #if defined(_KERNEL) 2707 EXPORT_SYMBOL(dnode_hold); 2708 EXPORT_SYMBOL(dnode_rele); 2709 EXPORT_SYMBOL(dnode_set_nlevels); 2710 EXPORT_SYMBOL(dnode_set_blksz); 2711 EXPORT_SYMBOL(dnode_free_range); 2712 EXPORT_SYMBOL(dnode_evict_dbufs); 2713 EXPORT_SYMBOL(dnode_evict_bonus); 2714 #endif 2715 2716 ZFS_MODULE_PARAM(zfs, zfs_, default_bs, INT, ZMOD_RW, 2717 "Default dnode block shift"); 2718 ZFS_MODULE_PARAM(zfs, zfs_, default_ibs, INT, ZMOD_RW, 2719 "Default dnode indirect block shift"); 2720