1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 */ 24 25 #include <sys/zfs_context.h> 26 #include <sys/dbuf.h> 27 #include <sys/dnode.h> 28 #include <sys/dmu.h> 29 #include <sys/dmu_impl.h> 30 #include <sys/dmu_tx.h> 31 #include <sys/dmu_objset.h> 32 #include <sys/dsl_dir.h> 33 #include <sys/dsl_dataset.h> 34 #include <sys/spa.h> 35 #include <sys/zio.h> 36 #include <sys/dmu_zfetch.h> 37 38 static int free_range_compar(const void *node1, const void *node2); 39 40 static kmem_cache_t *dnode_cache; 41 /* 42 * Define DNODE_STATS to turn on statistic gathering. By default, it is only 43 * turned on when DEBUG is also defined. 44 */ 45 #ifdef DEBUG 46 #define DNODE_STATS 47 #endif /* DEBUG */ 48 49 #ifdef DNODE_STATS 50 #define DNODE_STAT_ADD(stat) ((stat)++) 51 #else 52 #define DNODE_STAT_ADD(stat) /* nothing */ 53 #endif /* DNODE_STATS */ 54 55 static dnode_phys_t dnode_phys_zero; 56 57 int zfs_default_bs = SPA_MINBLOCKSHIFT; 58 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 59 60 static kmem_cbrc_t dnode_move(void *, void *, size_t, void *); 61 62 /* ARGSUSED */ 63 static int 64 dnode_cons(void *arg, void *unused, int kmflag) 65 { 66 dnode_t *dn = arg; 67 int i; 68 69 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 70 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 71 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 72 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 73 74 refcount_create(&dn->dn_holds); 75 refcount_create(&dn->dn_tx_holds); 76 list_link_init(&dn->dn_link); 77 78 bzero(&dn->dn_next_nblkptr[0], sizeof (dn->dn_next_nblkptr)); 79 bzero(&dn->dn_next_nlevels[0], sizeof (dn->dn_next_nlevels)); 80 bzero(&dn->dn_next_indblkshift[0], sizeof (dn->dn_next_indblkshift)); 81 bzero(&dn->dn_next_bonustype[0], sizeof (dn->dn_next_bonustype)); 82 bzero(&dn->dn_rm_spillblk[0], sizeof (dn->dn_rm_spillblk)); 83 bzero(&dn->dn_next_bonuslen[0], sizeof (dn->dn_next_bonuslen)); 84 bzero(&dn->dn_next_blksz[0], sizeof (dn->dn_next_blksz)); 85 86 for (i = 0; i < TXG_SIZE; i++) { 87 list_link_init(&dn->dn_dirty_link[i]); 88 avl_create(&dn->dn_ranges[i], free_range_compar, 89 sizeof (free_range_t), 90 offsetof(struct free_range, fr_node)); 91 list_create(&dn->dn_dirty_records[i], 92 sizeof (dbuf_dirty_record_t), 93 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 94 } 95 96 dn->dn_allocated_txg = 0; 97 dn->dn_free_txg = 0; 98 dn->dn_assigned_txg = 0; 99 dn->dn_dirtyctx = 0; 100 dn->dn_dirtyctx_firstset = NULL; 101 dn->dn_bonus = NULL; 102 dn->dn_have_spill = B_FALSE; 103 dn->dn_zio = NULL; 104 dn->dn_oldused = 0; 105 dn->dn_oldflags = 0; 106 dn->dn_olduid = 0; 107 dn->dn_oldgid = 0; 108 dn->dn_newuid = 0; 109 dn->dn_newgid = 0; 110 dn->dn_id_flags = 0; 111 112 dn->dn_dbufs_count = 0; 113 list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), 114 offsetof(dmu_buf_impl_t, db_link)); 115 116 dn->dn_moved = 0; 117 return (0); 118 } 119 120 /* ARGSUSED */ 121 static void 122 dnode_dest(void *arg, void *unused) 123 { 124 int i; 125 dnode_t *dn = arg; 126 127 rw_destroy(&dn->dn_struct_rwlock); 128 mutex_destroy(&dn->dn_mtx); 129 mutex_destroy(&dn->dn_dbufs_mtx); 130 cv_destroy(&dn->dn_notxholds); 131 refcount_destroy(&dn->dn_holds); 132 refcount_destroy(&dn->dn_tx_holds); 133 ASSERT(!list_link_active(&dn->dn_link)); 134 135 for (i = 0; i < TXG_SIZE; i++) { 136 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 137 avl_destroy(&dn->dn_ranges[i]); 138 list_destroy(&dn->dn_dirty_records[i]); 139 ASSERT3U(dn->dn_next_nblkptr[i], ==, 0); 140 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 141 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 142 ASSERT3U(dn->dn_next_bonustype[i], ==, 0); 143 ASSERT3U(dn->dn_rm_spillblk[i], ==, 0); 144 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 145 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 146 } 147 148 ASSERT3U(dn->dn_allocated_txg, ==, 0); 149 ASSERT3U(dn->dn_free_txg, ==, 0); 150 ASSERT3U(dn->dn_assigned_txg, ==, 0); 151 ASSERT3U(dn->dn_dirtyctx, ==, 0); 152 ASSERT3P(dn->dn_dirtyctx_firstset, ==, NULL); 153 ASSERT3P(dn->dn_bonus, ==, NULL); 154 ASSERT(!dn->dn_have_spill); 155 ASSERT3P(dn->dn_zio, ==, NULL); 156 ASSERT3U(dn->dn_oldused, ==, 0); 157 ASSERT3U(dn->dn_oldflags, ==, 0); 158 ASSERT3U(dn->dn_olduid, ==, 0); 159 ASSERT3U(dn->dn_oldgid, ==, 0); 160 ASSERT3U(dn->dn_newuid, ==, 0); 161 ASSERT3U(dn->dn_newgid, ==, 0); 162 ASSERT3U(dn->dn_id_flags, ==, 0); 163 164 ASSERT3U(dn->dn_dbufs_count, ==, 0); 165 list_destroy(&dn->dn_dbufs); 166 } 167 168 void 169 dnode_init(void) 170 { 171 ASSERT(dnode_cache == NULL); 172 dnode_cache = kmem_cache_create("dnode_t", 173 sizeof (dnode_t), 174 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 175 kmem_cache_set_move(dnode_cache, dnode_move); 176 } 177 178 void 179 dnode_fini(void) 180 { 181 kmem_cache_destroy(dnode_cache); 182 dnode_cache = NULL; 183 } 184 185 186 #ifdef ZFS_DEBUG 187 void 188 dnode_verify(dnode_t *dn) 189 { 190 int drop_struct_lock = FALSE; 191 192 ASSERT(dn->dn_phys); 193 ASSERT(dn->dn_objset); 194 ASSERT(dn->dn_handle->dnh_dnode == dn); 195 196 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 197 198 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 199 return; 200 201 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 202 rw_enter(&dn->dn_struct_rwlock, RW_READER); 203 drop_struct_lock = TRUE; 204 } 205 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 206 int i; 207 ASSERT3U(dn->dn_indblkshift, >=, 0); 208 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 209 if (dn->dn_datablkshift) { 210 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 211 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 212 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 213 } 214 ASSERT3U(dn->dn_nlevels, <=, 30); 215 ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); 216 ASSERT3U(dn->dn_nblkptr, >=, 1); 217 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 218 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 219 ASSERT3U(dn->dn_datablksz, ==, 220 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 221 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 222 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 223 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 224 for (i = 0; i < TXG_SIZE; i++) { 225 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 226 } 227 } 228 if (dn->dn_phys->dn_type != DMU_OT_NONE) 229 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 230 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 231 if (dn->dn_dbuf != NULL) { 232 ASSERT3P(dn->dn_phys, ==, 233 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 234 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 235 } 236 if (drop_struct_lock) 237 rw_exit(&dn->dn_struct_rwlock); 238 } 239 #endif 240 241 void 242 dnode_byteswap(dnode_phys_t *dnp) 243 { 244 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 245 int i; 246 247 if (dnp->dn_type == DMU_OT_NONE) { 248 bzero(dnp, sizeof (dnode_phys_t)); 249 return; 250 } 251 252 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 253 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 254 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 255 dnp->dn_used = BSWAP_64(dnp->dn_used); 256 257 /* 258 * dn_nblkptr is only one byte, so it's OK to read it in either 259 * byte order. We can't read dn_bouslen. 260 */ 261 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 262 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 263 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 264 buf64[i] = BSWAP_64(buf64[i]); 265 266 /* 267 * OK to check dn_bonuslen for zero, because it won't matter if 268 * we have the wrong byte order. This is necessary because the 269 * dnode dnode is smaller than a regular dnode. 270 */ 271 if (dnp->dn_bonuslen != 0) { 272 /* 273 * Note that the bonus length calculated here may be 274 * longer than the actual bonus buffer. This is because 275 * we always put the bonus buffer after the last block 276 * pointer (instead of packing it against the end of the 277 * dnode buffer). 278 */ 279 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 280 size_t len = DN_MAX_BONUSLEN - off; 281 ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); 282 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 283 } 284 285 /* Swap SPILL block if we have one */ 286 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 287 byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t)); 288 289 } 290 291 void 292 dnode_buf_byteswap(void *vbuf, size_t size) 293 { 294 dnode_phys_t *buf = vbuf; 295 int i; 296 297 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 298 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 299 300 size >>= DNODE_SHIFT; 301 for (i = 0; i < size; i++) { 302 dnode_byteswap(buf); 303 buf++; 304 } 305 } 306 307 static int 308 free_range_compar(const void *node1, const void *node2) 309 { 310 const free_range_t *rp1 = node1; 311 const free_range_t *rp2 = node2; 312 313 if (rp1->fr_blkid < rp2->fr_blkid) 314 return (-1); 315 else if (rp1->fr_blkid > rp2->fr_blkid) 316 return (1); 317 else return (0); 318 } 319 320 void 321 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 322 { 323 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 324 325 dnode_setdirty(dn, tx); 326 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 327 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 328 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 329 dn->dn_bonuslen = newsize; 330 if (newsize == 0) 331 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 332 else 333 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 334 rw_exit(&dn->dn_struct_rwlock); 335 } 336 337 void 338 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 339 { 340 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 341 dnode_setdirty(dn, tx); 342 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 343 dn->dn_bonustype = newtype; 344 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 345 rw_exit(&dn->dn_struct_rwlock); 346 } 347 348 void 349 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 350 { 351 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 352 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 353 dnode_setdirty(dn, tx); 354 dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; 355 dn->dn_have_spill = B_FALSE; 356 } 357 358 static void 359 dnode_setdblksz(dnode_t *dn, int size) 360 { 361 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 362 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 363 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 364 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 365 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 366 dn->dn_datablksz = size; 367 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 368 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 369 } 370 371 static dnode_t * 372 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 373 uint64_t object, dnode_handle_t *dnh) 374 { 375 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 376 377 ASSERT(!POINTER_IS_VALID(dn->dn_objset)); 378 dn->dn_moved = 0; 379 380 /* 381 * Defer setting dn_objset until the dnode is ready to be a candidate 382 * for the dnode_move() callback. 383 */ 384 dn->dn_object = object; 385 dn->dn_dbuf = db; 386 dn->dn_handle = dnh; 387 dn->dn_phys = dnp; 388 389 if (dnp->dn_datablkszsec) { 390 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 391 } else { 392 dn->dn_datablksz = 0; 393 dn->dn_datablkszsec = 0; 394 dn->dn_datablkshift = 0; 395 } 396 dn->dn_indblkshift = dnp->dn_indblkshift; 397 dn->dn_nlevels = dnp->dn_nlevels; 398 dn->dn_type = dnp->dn_type; 399 dn->dn_nblkptr = dnp->dn_nblkptr; 400 dn->dn_checksum = dnp->dn_checksum; 401 dn->dn_compress = dnp->dn_compress; 402 dn->dn_bonustype = dnp->dn_bonustype; 403 dn->dn_bonuslen = dnp->dn_bonuslen; 404 dn->dn_maxblkid = dnp->dn_maxblkid; 405 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 406 dn->dn_id_flags = 0; 407 408 dmu_zfetch_init(&dn->dn_zfetch, dn); 409 410 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 411 412 mutex_enter(&os->os_lock); 413 list_insert_head(&os->os_dnodes, dn); 414 membar_producer(); 415 /* 416 * Everything else must be valid before assigning dn_objset makes the 417 * dnode eligible for dnode_move(). 418 */ 419 dn->dn_objset = os; 420 mutex_exit(&os->os_lock); 421 422 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 423 return (dn); 424 } 425 426 /* 427 * Caller must be holding the dnode handle, which is released upon return. 428 */ 429 static void 430 dnode_destroy(dnode_t *dn) 431 { 432 objset_t *os = dn->dn_objset; 433 434 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 435 436 mutex_enter(&os->os_lock); 437 POINTER_INVALIDATE(&dn->dn_objset); 438 list_remove(&os->os_dnodes, dn); 439 mutex_exit(&os->os_lock); 440 441 /* the dnode can no longer move, so we can release the handle */ 442 zrl_remove(&dn->dn_handle->dnh_zrlock); 443 444 dn->dn_allocated_txg = 0; 445 dn->dn_free_txg = 0; 446 dn->dn_assigned_txg = 0; 447 448 dn->dn_dirtyctx = 0; 449 if (dn->dn_dirtyctx_firstset != NULL) { 450 kmem_free(dn->dn_dirtyctx_firstset, 1); 451 dn->dn_dirtyctx_firstset = NULL; 452 } 453 if (dn->dn_bonus != NULL) { 454 mutex_enter(&dn->dn_bonus->db_mtx); 455 dbuf_evict(dn->dn_bonus); 456 dn->dn_bonus = NULL; 457 } 458 dn->dn_zio = NULL; 459 460 dn->dn_have_spill = B_FALSE; 461 dn->dn_oldused = 0; 462 dn->dn_oldflags = 0; 463 dn->dn_olduid = 0; 464 dn->dn_oldgid = 0; 465 dn->dn_newuid = 0; 466 dn->dn_newgid = 0; 467 dn->dn_id_flags = 0; 468 469 dmu_zfetch_rele(&dn->dn_zfetch); 470 kmem_cache_free(dnode_cache, dn); 471 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 472 } 473 474 void 475 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 476 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 477 { 478 int i; 479 480 if (blocksize == 0) 481 blocksize = 1 << zfs_default_bs; 482 else if (blocksize > SPA_MAXBLOCKSIZE) 483 blocksize = SPA_MAXBLOCKSIZE; 484 else 485 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 486 487 if (ibs == 0) 488 ibs = zfs_default_ibs; 489 490 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 491 492 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 493 dn->dn_object, tx->tx_txg, blocksize, ibs); 494 495 ASSERT(dn->dn_type == DMU_OT_NONE); 496 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 497 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 498 ASSERT(ot != DMU_OT_NONE); 499 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 500 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 501 (bonustype == DMU_OT_SA && bonuslen == 0) || 502 (bonustype != DMU_OT_NONE && bonuslen != 0)); 503 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 504 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 505 ASSERT(dn->dn_type == DMU_OT_NONE); 506 ASSERT3U(dn->dn_maxblkid, ==, 0); 507 ASSERT3U(dn->dn_allocated_txg, ==, 0); 508 ASSERT3U(dn->dn_assigned_txg, ==, 0); 509 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 510 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 511 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 512 513 for (i = 0; i < TXG_SIZE; i++) { 514 ASSERT3U(dn->dn_next_nblkptr[i], ==, 0); 515 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 516 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 517 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 518 ASSERT3U(dn->dn_next_bonustype[i], ==, 0); 519 ASSERT3U(dn->dn_rm_spillblk[i], ==, 0); 520 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 521 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 522 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 523 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 524 } 525 526 dn->dn_type = ot; 527 dnode_setdblksz(dn, blocksize); 528 dn->dn_indblkshift = ibs; 529 dn->dn_nlevels = 1; 530 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 531 dn->dn_nblkptr = 1; 532 else 533 dn->dn_nblkptr = 1 + 534 ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 535 dn->dn_bonustype = bonustype; 536 dn->dn_bonuslen = bonuslen; 537 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 538 dn->dn_compress = ZIO_COMPRESS_INHERIT; 539 dn->dn_dirtyctx = 0; 540 541 dn->dn_free_txg = 0; 542 if (dn->dn_dirtyctx_firstset) { 543 kmem_free(dn->dn_dirtyctx_firstset, 1); 544 dn->dn_dirtyctx_firstset = NULL; 545 } 546 547 dn->dn_allocated_txg = tx->tx_txg; 548 dn->dn_id_flags = 0; 549 550 dnode_setdirty(dn, tx); 551 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 552 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 553 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 554 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 555 } 556 557 void 558 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 559 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 560 { 561 int nblkptr; 562 563 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 564 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 565 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 566 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 567 ASSERT(tx->tx_txg != 0); 568 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 569 (bonustype != DMU_OT_NONE && bonuslen != 0) || 570 (bonustype == DMU_OT_SA && bonuslen == 0)); 571 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 572 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 573 574 /* clean up any unreferenced dbufs */ 575 dnode_evict_dbufs(dn); 576 577 dn->dn_id_flags = 0; 578 579 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 580 dnode_setdirty(dn, tx); 581 if (dn->dn_datablksz != blocksize) { 582 /* change blocksize */ 583 ASSERT(dn->dn_maxblkid == 0 && 584 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 585 dnode_block_freed(dn, 0))); 586 dnode_setdblksz(dn, blocksize); 587 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 588 } 589 if (dn->dn_bonuslen != bonuslen) 590 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 591 592 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 593 nblkptr = 1; 594 else 595 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 596 if (dn->dn_bonustype != bonustype) 597 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 598 if (dn->dn_nblkptr != nblkptr) 599 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 600 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 601 dbuf_rm_spill(dn, tx); 602 dnode_rm_spill(dn, tx); 603 } 604 rw_exit(&dn->dn_struct_rwlock); 605 606 /* change type */ 607 dn->dn_type = ot; 608 609 /* change bonus size and type */ 610 mutex_enter(&dn->dn_mtx); 611 dn->dn_bonustype = bonustype; 612 dn->dn_bonuslen = bonuslen; 613 dn->dn_nblkptr = nblkptr; 614 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 615 dn->dn_compress = ZIO_COMPRESS_INHERIT; 616 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 617 618 /* fix up the bonus db_size */ 619 if (dn->dn_bonus) { 620 dn->dn_bonus->db.db_size = 621 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 622 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 623 } 624 625 dn->dn_allocated_txg = tx->tx_txg; 626 mutex_exit(&dn->dn_mtx); 627 } 628 629 #ifdef DNODE_STATS 630 static struct { 631 uint64_t dms_dnode_invalid; 632 uint64_t dms_dnode_recheck1; 633 uint64_t dms_dnode_recheck2; 634 uint64_t dms_dnode_special; 635 uint64_t dms_dnode_handle; 636 uint64_t dms_dnode_rwlock; 637 uint64_t dms_dnode_active; 638 } dnode_move_stats; 639 #endif /* DNODE_STATS */ 640 641 static void 642 dnode_move_impl(dnode_t *odn, dnode_t *ndn) 643 { 644 int i; 645 646 ASSERT(!RW_LOCK_HELD(&odn->dn_struct_rwlock)); 647 ASSERT(MUTEX_NOT_HELD(&odn->dn_mtx)); 648 ASSERT(MUTEX_NOT_HELD(&odn->dn_dbufs_mtx)); 649 ASSERT(!RW_LOCK_HELD(&odn->dn_zfetch.zf_rwlock)); 650 651 /* Copy fields. */ 652 ndn->dn_objset = odn->dn_objset; 653 ndn->dn_object = odn->dn_object; 654 ndn->dn_dbuf = odn->dn_dbuf; 655 ndn->dn_handle = odn->dn_handle; 656 ndn->dn_phys = odn->dn_phys; 657 ndn->dn_type = odn->dn_type; 658 ndn->dn_bonuslen = odn->dn_bonuslen; 659 ndn->dn_bonustype = odn->dn_bonustype; 660 ndn->dn_nblkptr = odn->dn_nblkptr; 661 ndn->dn_checksum = odn->dn_checksum; 662 ndn->dn_compress = odn->dn_compress; 663 ndn->dn_nlevels = odn->dn_nlevels; 664 ndn->dn_indblkshift = odn->dn_indblkshift; 665 ndn->dn_datablkshift = odn->dn_datablkshift; 666 ndn->dn_datablkszsec = odn->dn_datablkszsec; 667 ndn->dn_datablksz = odn->dn_datablksz; 668 ndn->dn_maxblkid = odn->dn_maxblkid; 669 bcopy(&odn->dn_next_nblkptr[0], &ndn->dn_next_nblkptr[0], 670 sizeof (odn->dn_next_nblkptr)); 671 bcopy(&odn->dn_next_nlevels[0], &ndn->dn_next_nlevels[0], 672 sizeof (odn->dn_next_nlevels)); 673 bcopy(&odn->dn_next_indblkshift[0], &ndn->dn_next_indblkshift[0], 674 sizeof (odn->dn_next_indblkshift)); 675 bcopy(&odn->dn_next_bonustype[0], &ndn->dn_next_bonustype[0], 676 sizeof (odn->dn_next_bonustype)); 677 bcopy(&odn->dn_rm_spillblk[0], &ndn->dn_rm_spillblk[0], 678 sizeof (odn->dn_rm_spillblk)); 679 bcopy(&odn->dn_next_bonuslen[0], &ndn->dn_next_bonuslen[0], 680 sizeof (odn->dn_next_bonuslen)); 681 bcopy(&odn->dn_next_blksz[0], &ndn->dn_next_blksz[0], 682 sizeof (odn->dn_next_blksz)); 683 for (i = 0; i < TXG_SIZE; i++) { 684 list_move_tail(&ndn->dn_dirty_records[i], 685 &odn->dn_dirty_records[i]); 686 } 687 bcopy(&odn->dn_ranges[0], &ndn->dn_ranges[0], sizeof (odn->dn_ranges)); 688 ndn->dn_allocated_txg = odn->dn_allocated_txg; 689 ndn->dn_free_txg = odn->dn_free_txg; 690 ndn->dn_assigned_txg = odn->dn_assigned_txg; 691 ndn->dn_dirtyctx = odn->dn_dirtyctx; 692 ndn->dn_dirtyctx_firstset = odn->dn_dirtyctx_firstset; 693 ASSERT(refcount_count(&odn->dn_tx_holds) == 0); 694 refcount_transfer(&ndn->dn_holds, &odn->dn_holds); 695 ASSERT(list_is_empty(&ndn->dn_dbufs)); 696 list_move_tail(&ndn->dn_dbufs, &odn->dn_dbufs); 697 ndn->dn_dbufs_count = odn->dn_dbufs_count; 698 ndn->dn_bonus = odn->dn_bonus; 699 ndn->dn_have_spill = odn->dn_have_spill; 700 ndn->dn_zio = odn->dn_zio; 701 ndn->dn_oldused = odn->dn_oldused; 702 ndn->dn_oldflags = odn->dn_oldflags; 703 ndn->dn_olduid = odn->dn_olduid; 704 ndn->dn_oldgid = odn->dn_oldgid; 705 ndn->dn_newuid = odn->dn_newuid; 706 ndn->dn_newgid = odn->dn_newgid; 707 ndn->dn_id_flags = odn->dn_id_flags; 708 dmu_zfetch_init(&ndn->dn_zfetch, NULL); 709 list_move_tail(&ndn->dn_zfetch.zf_stream, &odn->dn_zfetch.zf_stream); 710 ndn->dn_zfetch.zf_dnode = odn->dn_zfetch.zf_dnode; 711 ndn->dn_zfetch.zf_stream_cnt = odn->dn_zfetch.zf_stream_cnt; 712 ndn->dn_zfetch.zf_alloc_fail = odn->dn_zfetch.zf_alloc_fail; 713 714 /* 715 * Update back pointers. Updating the handle fixes the back pointer of 716 * every descendant dbuf as well as the bonus dbuf. 717 */ 718 ASSERT(ndn->dn_handle->dnh_dnode == odn); 719 ndn->dn_handle->dnh_dnode = ndn; 720 if (ndn->dn_zfetch.zf_dnode == odn) { 721 ndn->dn_zfetch.zf_dnode = ndn; 722 } 723 724 /* 725 * Invalidate the original dnode by clearing all of its back pointers. 726 */ 727 odn->dn_dbuf = NULL; 728 odn->dn_handle = NULL; 729 list_create(&odn->dn_dbufs, sizeof (dmu_buf_impl_t), 730 offsetof(dmu_buf_impl_t, db_link)); 731 odn->dn_dbufs_count = 0; 732 odn->dn_bonus = NULL; 733 odn->dn_zfetch.zf_dnode = NULL; 734 735 /* 736 * Set the low bit of the objset pointer to ensure that dnode_move() 737 * recognizes the dnode as invalid in any subsequent callback. 738 */ 739 POINTER_INVALIDATE(&odn->dn_objset); 740 741 /* 742 * Satisfy the destructor. 743 */ 744 for (i = 0; i < TXG_SIZE; i++) { 745 list_create(&odn->dn_dirty_records[i], 746 sizeof (dbuf_dirty_record_t), 747 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 748 odn->dn_ranges[i].avl_root = NULL; 749 odn->dn_ranges[i].avl_numnodes = 0; 750 odn->dn_next_nlevels[i] = 0; 751 odn->dn_next_indblkshift[i] = 0; 752 odn->dn_next_bonustype[i] = 0; 753 odn->dn_rm_spillblk[i] = 0; 754 odn->dn_next_bonuslen[i] = 0; 755 odn->dn_next_blksz[i] = 0; 756 } 757 odn->dn_allocated_txg = 0; 758 odn->dn_free_txg = 0; 759 odn->dn_assigned_txg = 0; 760 odn->dn_dirtyctx = 0; 761 odn->dn_dirtyctx_firstset = NULL; 762 odn->dn_have_spill = B_FALSE; 763 odn->dn_zio = NULL; 764 odn->dn_oldused = 0; 765 odn->dn_oldflags = 0; 766 odn->dn_olduid = 0; 767 odn->dn_oldgid = 0; 768 odn->dn_newuid = 0; 769 odn->dn_newgid = 0; 770 odn->dn_id_flags = 0; 771 772 /* 773 * Mark the dnode. 774 */ 775 ndn->dn_moved = 1; 776 odn->dn_moved = (uint8_t)-1; 777 } 778 779 #ifdef _KERNEL 780 /*ARGSUSED*/ 781 static kmem_cbrc_t 782 dnode_move(void *buf, void *newbuf, size_t size, void *arg) 783 { 784 dnode_t *odn = buf, *ndn = newbuf; 785 objset_t *os; 786 int64_t refcount; 787 uint32_t dbufs; 788 789 /* 790 * The dnode is on the objset's list of known dnodes if the objset 791 * pointer is valid. We set the low bit of the objset pointer when 792 * freeing the dnode to invalidate it, and the memory patterns written 793 * by kmem (baddcafe and deadbeef) set at least one of the two low bits. 794 * A newly created dnode sets the objset pointer last of all to indicate 795 * that the dnode is known and in a valid state to be moved by this 796 * function. 797 */ 798 os = odn->dn_objset; 799 if (!POINTER_IS_VALID(os)) { 800 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_invalid); 801 return (KMEM_CBRC_DONT_KNOW); 802 } 803 804 /* 805 * Ensure that the objset does not go away during the move. 806 */ 807 rw_enter(&os_lock, RW_WRITER); 808 if (os != odn->dn_objset) { 809 rw_exit(&os_lock); 810 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck1); 811 return (KMEM_CBRC_DONT_KNOW); 812 } 813 814 /* 815 * If the dnode is still valid, then so is the objset. We know that no 816 * valid objset can be freed while we hold os_lock, so we can safely 817 * ensure that the objset remains in use. 818 */ 819 mutex_enter(&os->os_lock); 820 821 /* 822 * Recheck the objset pointer in case the dnode was removed just before 823 * acquiring the lock. 824 */ 825 if (os != odn->dn_objset) { 826 mutex_exit(&os->os_lock); 827 rw_exit(&os_lock); 828 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_recheck2); 829 return (KMEM_CBRC_DONT_KNOW); 830 } 831 832 /* 833 * At this point we know that as long as we hold os->os_lock, the dnode 834 * cannot be freed and fields within the dnode can be safely accessed. 835 * The objset listing this dnode cannot go away as long as this dnode is 836 * on its list. 837 */ 838 rw_exit(&os_lock); 839 if (DMU_OBJECT_IS_SPECIAL(odn->dn_object)) { 840 mutex_exit(&os->os_lock); 841 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_special); 842 return (KMEM_CBRC_NO); 843 } 844 ASSERT(odn->dn_dbuf != NULL); /* only "special" dnodes have no parent */ 845 846 /* 847 * Lock the dnode handle to prevent the dnode from obtaining any new 848 * holds. This also prevents the descendant dbufs and the bonus dbuf 849 * from accessing the dnode, so that we can discount their holds. The 850 * handle is safe to access because we know that while the dnode cannot 851 * go away, neither can its handle. Once we hold dnh_zrlock, we can 852 * safely move any dnode referenced only by dbufs. 853 */ 854 if (!zrl_tryenter(&odn->dn_handle->dnh_zrlock)) { 855 mutex_exit(&os->os_lock); 856 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_handle); 857 return (KMEM_CBRC_LATER); 858 } 859 860 /* 861 * Ensure a consistent view of the dnode's holds and the dnode's dbufs. 862 * We need to guarantee that there is a hold for every dbuf in order to 863 * determine whether the dnode is actively referenced. Falsely matching 864 * a dbuf to an active hold would lead to an unsafe move. It's possible 865 * that a thread already having an active dnode hold is about to add a 866 * dbuf, and we can't compare hold and dbuf counts while the add is in 867 * progress. 868 */ 869 if (!rw_tryenter(&odn->dn_struct_rwlock, RW_WRITER)) { 870 zrl_exit(&odn->dn_handle->dnh_zrlock); 871 mutex_exit(&os->os_lock); 872 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_rwlock); 873 return (KMEM_CBRC_LATER); 874 } 875 876 /* 877 * A dbuf may be removed (evicted) without an active dnode hold. In that 878 * case, the dbuf count is decremented under the handle lock before the 879 * dbuf's hold is released. This order ensures that if we count the hold 880 * after the dbuf is removed but before its hold is released, we will 881 * treat the unmatched hold as active and exit safely. If we count the 882 * hold before the dbuf is removed, the hold is discounted, and the 883 * removal is blocked until the move completes. 884 */ 885 refcount = refcount_count(&odn->dn_holds); 886 ASSERT(refcount >= 0); 887 dbufs = odn->dn_dbufs_count; 888 889 /* We can't have more dbufs than dnode holds. */ 890 ASSERT3U(dbufs, <=, refcount); 891 DTRACE_PROBE3(dnode__move, dnode_t *, odn, int64_t, refcount, 892 uint32_t, dbufs); 893 894 if (refcount > dbufs) { 895 rw_exit(&odn->dn_struct_rwlock); 896 zrl_exit(&odn->dn_handle->dnh_zrlock); 897 mutex_exit(&os->os_lock); 898 DNODE_STAT_ADD(dnode_move_stats.dms_dnode_active); 899 return (KMEM_CBRC_LATER); 900 } 901 902 rw_exit(&odn->dn_struct_rwlock); 903 904 /* 905 * At this point we know that anyone with a hold on the dnode is not 906 * actively referencing it. The dnode is known and in a valid state to 907 * move. We're holding the locks needed to execute the critical section. 908 */ 909 dnode_move_impl(odn, ndn); 910 911 list_link_replace(&odn->dn_link, &ndn->dn_link); 912 /* If the dnode was safe to move, the refcount cannot have changed. */ 913 ASSERT(refcount == refcount_count(&ndn->dn_holds)); 914 ASSERT(dbufs == ndn->dn_dbufs_count); 915 zrl_exit(&ndn->dn_handle->dnh_zrlock); /* handle has moved */ 916 mutex_exit(&os->os_lock); 917 918 return (KMEM_CBRC_YES); 919 } 920 #endif /* _KERNEL */ 921 922 void 923 dnode_special_close(dnode_handle_t *dnh) 924 { 925 dnode_t *dn = dnh->dnh_dnode; 926 927 /* 928 * Wait for final references to the dnode to clear. This can 929 * only happen if the arc is asyncronously evicting state that 930 * has a hold on this dnode while we are trying to evict this 931 * dnode. 932 */ 933 while (refcount_count(&dn->dn_holds) > 0) 934 delay(1); 935 zrl_add(&dnh->dnh_zrlock); 936 dnode_destroy(dn); /* implicit zrl_remove() */ 937 zrl_destroy(&dnh->dnh_zrlock); 938 dnh->dnh_dnode = NULL; 939 } 940 941 dnode_t * 942 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object, 943 dnode_handle_t *dnh) 944 { 945 dnode_t *dn = dnode_create(os, dnp, NULL, object, dnh); 946 dnh->dnh_dnode = dn; 947 zrl_init(&dnh->dnh_zrlock); 948 DNODE_VERIFY(dn); 949 return (dn); 950 } 951 952 static void 953 dnode_buf_pageout(dmu_buf_t *db, void *arg) 954 { 955 dnode_children_t *children_dnodes = arg; 956 int i; 957 int epb = db->db_size >> DNODE_SHIFT; 958 959 ASSERT(epb == children_dnodes->dnc_count); 960 961 for (i = 0; i < epb; i++) { 962 dnode_handle_t *dnh = &children_dnodes->dnc_children[i]; 963 dnode_t *dn; 964 965 /* 966 * The dnode handle lock guards against the dnode moving to 967 * another valid address, so there is no need here to guard 968 * against changes to or from NULL. 969 */ 970 if (dnh->dnh_dnode == NULL) { 971 zrl_destroy(&dnh->dnh_zrlock); 972 continue; 973 } 974 975 zrl_add(&dnh->dnh_zrlock); 976 dn = dnh->dnh_dnode; 977 /* 978 * If there are holds on this dnode, then there should 979 * be holds on the dnode's containing dbuf as well; thus 980 * it wouldn't be eligible for eviction and this function 981 * would not have been called. 982 */ 983 ASSERT(refcount_is_zero(&dn->dn_holds)); 984 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 985 986 dnode_destroy(dn); /* implicit zrl_remove() */ 987 zrl_destroy(&dnh->dnh_zrlock); 988 dnh->dnh_dnode = NULL; 989 } 990 kmem_free(children_dnodes, sizeof (dnode_children_t) + 991 (epb - 1) * sizeof (dnode_handle_t)); 992 } 993 994 /* 995 * errors: 996 * EINVAL - invalid object number. 997 * EIO - i/o error. 998 * succeeds even for free dnodes. 999 */ 1000 int 1001 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 1002 void *tag, dnode_t **dnp) 1003 { 1004 int epb, idx, err; 1005 int drop_struct_lock = FALSE; 1006 int type; 1007 uint64_t blk; 1008 dnode_t *mdn, *dn; 1009 dmu_buf_impl_t *db; 1010 dnode_children_t *children_dnodes; 1011 dnode_handle_t *dnh; 1012 1013 /* 1014 * If you are holding the spa config lock as writer, you shouldn't 1015 * be asking the DMU to do *anything* unless it's the root pool 1016 * which may require us to read from the root filesystem while 1017 * holding some (not all) of the locks as writer. 1018 */ 1019 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 1020 (spa_is_root(os->os_spa) && 1021 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER))); 1022 1023 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 1024 dn = (object == DMU_USERUSED_OBJECT) ? 1025 DMU_USERUSED_DNODE(os) : DMU_GROUPUSED_DNODE(os); 1026 if (dn == NULL) 1027 return (ENOENT); 1028 type = dn->dn_type; 1029 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 1030 return (ENOENT); 1031 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 1032 return (EEXIST); 1033 DNODE_VERIFY(dn); 1034 (void) refcount_add(&dn->dn_holds, tag); 1035 *dnp = dn; 1036 return (0); 1037 } 1038 1039 if (object == 0 || object >= DN_MAX_OBJECT) 1040 return (EINVAL); 1041 1042 mdn = DMU_META_DNODE(os); 1043 ASSERT(mdn->dn_object == DMU_META_DNODE_OBJECT); 1044 1045 DNODE_VERIFY(mdn); 1046 1047 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 1048 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 1049 drop_struct_lock = TRUE; 1050 } 1051 1052 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 1053 1054 db = dbuf_hold(mdn, blk, FTAG); 1055 if (drop_struct_lock) 1056 rw_exit(&mdn->dn_struct_rwlock); 1057 if (db == NULL) 1058 return (EIO); 1059 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 1060 if (err) { 1061 dbuf_rele(db, FTAG); 1062 return (err); 1063 } 1064 1065 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 1066 epb = db->db.db_size >> DNODE_SHIFT; 1067 1068 idx = object & (epb-1); 1069 1070 ASSERT(DB_DNODE(db)->dn_type == DMU_OT_DNODE); 1071 children_dnodes = dmu_buf_get_user(&db->db); 1072 if (children_dnodes == NULL) { 1073 int i; 1074 dnode_children_t *winner; 1075 children_dnodes = kmem_alloc(sizeof (dnode_children_t) + 1076 (epb - 1) * sizeof (dnode_handle_t), KM_SLEEP); 1077 children_dnodes->dnc_count = epb; 1078 dnh = &children_dnodes->dnc_children[0]; 1079 for (i = 0; i < epb; i++) { 1080 zrl_init(&dnh[i].dnh_zrlock); 1081 dnh[i].dnh_dnode = NULL; 1082 } 1083 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 1084 dnode_buf_pageout)) { 1085 kmem_free(children_dnodes, sizeof (dnode_children_t) + 1086 (epb - 1) * sizeof (dnode_handle_t)); 1087 children_dnodes = winner; 1088 } 1089 } 1090 ASSERT(children_dnodes->dnc_count == epb); 1091 1092 dnh = &children_dnodes->dnc_children[idx]; 1093 zrl_add(&dnh->dnh_zrlock); 1094 if ((dn = dnh->dnh_dnode) == NULL) { 1095 dnode_phys_t *phys = (dnode_phys_t *)db->db.db_data+idx; 1096 dnode_t *winner; 1097 1098 dn = dnode_create(os, phys, db, object, dnh); 1099 winner = atomic_cas_ptr(&dnh->dnh_dnode, NULL, dn); 1100 if (winner != NULL) { 1101 zrl_add(&dnh->dnh_zrlock); 1102 dnode_destroy(dn); /* implicit zrl_remove() */ 1103 dn = winner; 1104 } 1105 } 1106 1107 mutex_enter(&dn->dn_mtx); 1108 type = dn->dn_type; 1109 if (dn->dn_free_txg || 1110 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 1111 ((flag & DNODE_MUST_BE_FREE) && 1112 (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) { 1113 mutex_exit(&dn->dn_mtx); 1114 zrl_remove(&dnh->dnh_zrlock); 1115 dbuf_rele(db, FTAG); 1116 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 1117 } 1118 mutex_exit(&dn->dn_mtx); 1119 1120 if (refcount_add(&dn->dn_holds, tag) == 1) 1121 dbuf_add_ref(db, dnh); 1122 /* Now we can rely on the hold to prevent the dnode from moving. */ 1123 zrl_remove(&dnh->dnh_zrlock); 1124 1125 DNODE_VERIFY(dn); 1126 ASSERT3P(dn->dn_dbuf, ==, db); 1127 ASSERT3U(dn->dn_object, ==, object); 1128 dbuf_rele(db, FTAG); 1129 1130 *dnp = dn; 1131 return (0); 1132 } 1133 1134 /* 1135 * Return held dnode if the object is allocated, NULL if not. 1136 */ 1137 int 1138 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 1139 { 1140 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 1141 } 1142 1143 /* 1144 * Can only add a reference if there is already at least one 1145 * reference on the dnode. Returns FALSE if unable to add a 1146 * new reference. 1147 */ 1148 boolean_t 1149 dnode_add_ref(dnode_t *dn, void *tag) 1150 { 1151 mutex_enter(&dn->dn_mtx); 1152 if (refcount_is_zero(&dn->dn_holds)) { 1153 mutex_exit(&dn->dn_mtx); 1154 return (FALSE); 1155 } 1156 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 1157 mutex_exit(&dn->dn_mtx); 1158 return (TRUE); 1159 } 1160 1161 void 1162 dnode_rele(dnode_t *dn, void *tag) 1163 { 1164 uint64_t refs; 1165 /* Get while the hold prevents the dnode from moving. */ 1166 dmu_buf_impl_t *db = dn->dn_dbuf; 1167 dnode_handle_t *dnh = dn->dn_handle; 1168 1169 mutex_enter(&dn->dn_mtx); 1170 refs = refcount_remove(&dn->dn_holds, tag); 1171 mutex_exit(&dn->dn_mtx); 1172 1173 /* 1174 * It's unsafe to release the last hold on a dnode by dnode_rele() or 1175 * indirectly by dbuf_rele() while relying on the dnode handle to 1176 * prevent the dnode from moving, since releasing the last hold could 1177 * result in the dnode's parent dbuf evicting its dnode handles. For 1178 * that reason anyone calling dnode_rele() or dbuf_rele() without some 1179 * other direct or indirect hold on the dnode must first drop the dnode 1180 * handle. 1181 */ 1182 ASSERT(refs > 0 || dnh->dnh_zrlock.zr_owner != curthread); 1183 1184 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 1185 if (refs == 0 && db != NULL) { 1186 /* 1187 * Another thread could add a hold to the dnode handle in 1188 * dnode_hold_impl() while holding the parent dbuf. Since the 1189 * hold on the parent dbuf prevents the handle from being 1190 * destroyed, the hold on the handle is OK. We can't yet assert 1191 * that the handle has zero references, but that will be 1192 * asserted anyway when the handle gets destroyed. 1193 */ 1194 dbuf_rele(db, dnh); 1195 } 1196 } 1197 1198 void 1199 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 1200 { 1201 objset_t *os = dn->dn_objset; 1202 uint64_t txg = tx->tx_txg; 1203 1204 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 1205 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1206 return; 1207 } 1208 1209 DNODE_VERIFY(dn); 1210 1211 #ifdef ZFS_DEBUG 1212 mutex_enter(&dn->dn_mtx); 1213 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 1214 ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); 1215 mutex_exit(&dn->dn_mtx); 1216 #endif 1217 1218 /* 1219 * Determine old uid/gid when necessary 1220 */ 1221 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 1222 1223 mutex_enter(&os->os_lock); 1224 1225 /* 1226 * If we are already marked dirty, we're done. 1227 */ 1228 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 1229 mutex_exit(&os->os_lock); 1230 return; 1231 } 1232 1233 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 1234 ASSERT(dn->dn_datablksz != 0); 1235 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 1236 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 1237 ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0); 1238 1239 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 1240 dn->dn_object, txg); 1241 1242 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 1243 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 1244 } else { 1245 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 1246 } 1247 1248 mutex_exit(&os->os_lock); 1249 1250 /* 1251 * The dnode maintains a hold on its containing dbuf as 1252 * long as there are holds on it. Each instantiated child 1253 * dbuf maintains a hold on the dnode. When the last child 1254 * drops its hold, the dnode will drop its hold on the 1255 * containing dbuf. We add a "dirty hold" here so that the 1256 * dnode will hang around after we finish processing its 1257 * children. 1258 */ 1259 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 1260 1261 (void) dbuf_dirty(dn->dn_dbuf, tx); 1262 1263 dsl_dataset_dirty(os->os_dsl_dataset, tx); 1264 } 1265 1266 void 1267 dnode_free(dnode_t *dn, dmu_tx_t *tx) 1268 { 1269 int txgoff = tx->tx_txg & TXG_MASK; 1270 1271 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 1272 1273 /* we should be the only holder... hopefully */ 1274 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 1275 1276 mutex_enter(&dn->dn_mtx); 1277 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 1278 mutex_exit(&dn->dn_mtx); 1279 return; 1280 } 1281 dn->dn_free_txg = tx->tx_txg; 1282 mutex_exit(&dn->dn_mtx); 1283 1284 /* 1285 * If the dnode is already dirty, it needs to be moved from 1286 * the dirty list to the free list. 1287 */ 1288 mutex_enter(&dn->dn_objset->os_lock); 1289 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 1290 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 1291 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 1292 mutex_exit(&dn->dn_objset->os_lock); 1293 } else { 1294 mutex_exit(&dn->dn_objset->os_lock); 1295 dnode_setdirty(dn, tx); 1296 } 1297 } 1298 1299 /* 1300 * Try to change the block size for the indicated dnode. This can only 1301 * succeed if there are no blocks allocated or dirty beyond first block 1302 */ 1303 int 1304 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 1305 { 1306 dmu_buf_impl_t *db, *db_next; 1307 int err; 1308 1309 if (size == 0) 1310 size = SPA_MINBLOCKSIZE; 1311 if (size > SPA_MAXBLOCKSIZE) 1312 size = SPA_MAXBLOCKSIZE; 1313 else 1314 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 1315 1316 if (ibs == dn->dn_indblkshift) 1317 ibs = 0; 1318 1319 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 1320 return (0); 1321 1322 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1323 1324 /* Check for any allocated blocks beyond the first */ 1325 if (dn->dn_phys->dn_maxblkid != 0) 1326 goto fail; 1327 1328 mutex_enter(&dn->dn_dbufs_mtx); 1329 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 1330 db_next = list_next(&dn->dn_dbufs, db); 1331 1332 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 1333 db->db_blkid != DMU_SPILL_BLKID) { 1334 mutex_exit(&dn->dn_dbufs_mtx); 1335 goto fail; 1336 } 1337 } 1338 mutex_exit(&dn->dn_dbufs_mtx); 1339 1340 if (ibs && dn->dn_nlevels != 1) 1341 goto fail; 1342 1343 /* resize the old block */ 1344 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 1345 if (err == 0) 1346 dbuf_new_size(db, size, tx); 1347 else if (err != ENOENT) 1348 goto fail; 1349 1350 dnode_setdblksz(dn, size); 1351 dnode_setdirty(dn, tx); 1352 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 1353 if (ibs) { 1354 dn->dn_indblkshift = ibs; 1355 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 1356 } 1357 /* rele after we have fixed the blocksize in the dnode */ 1358 if (db) 1359 dbuf_rele(db, FTAG); 1360 1361 rw_exit(&dn->dn_struct_rwlock); 1362 return (0); 1363 1364 fail: 1365 rw_exit(&dn->dn_struct_rwlock); 1366 return (ENOTSUP); 1367 } 1368 1369 /* read-holding callers must not rely on the lock being continuously held */ 1370 void 1371 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 1372 { 1373 uint64_t txgoff = tx->tx_txg & TXG_MASK; 1374 int epbs, new_nlevels; 1375 uint64_t sz; 1376 1377 ASSERT(blkid != DMU_BONUS_BLKID); 1378 1379 ASSERT(have_read ? 1380 RW_READ_HELD(&dn->dn_struct_rwlock) : 1381 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 1382 1383 /* 1384 * if we have a read-lock, check to see if we need to do any work 1385 * before upgrading to a write-lock. 1386 */ 1387 if (have_read) { 1388 if (blkid <= dn->dn_maxblkid) 1389 return; 1390 1391 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 1392 rw_exit(&dn->dn_struct_rwlock); 1393 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1394 } 1395 } 1396 1397 if (blkid <= dn->dn_maxblkid) 1398 goto out; 1399 1400 dn->dn_maxblkid = blkid; 1401 1402 /* 1403 * Compute the number of levels necessary to support the new maxblkid. 1404 */ 1405 new_nlevels = 1; 1406 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1407 for (sz = dn->dn_nblkptr; 1408 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 1409 new_nlevels++; 1410 1411 if (new_nlevels > dn->dn_nlevels) { 1412 int old_nlevels = dn->dn_nlevels; 1413 dmu_buf_impl_t *db; 1414 list_t *list; 1415 dbuf_dirty_record_t *new, *dr, *dr_next; 1416 1417 dn->dn_nlevels = new_nlevels; 1418 1419 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 1420 dn->dn_next_nlevels[txgoff] = new_nlevels; 1421 1422 /* dirty the left indirects */ 1423 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 1424 ASSERT(db != NULL); 1425 new = dbuf_dirty(db, tx); 1426 dbuf_rele(db, FTAG); 1427 1428 /* transfer the dirty records to the new indirect */ 1429 mutex_enter(&dn->dn_mtx); 1430 mutex_enter(&new->dt.di.dr_mtx); 1431 list = &dn->dn_dirty_records[txgoff]; 1432 for (dr = list_head(list); dr; dr = dr_next) { 1433 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 1434 if (dr->dr_dbuf->db_level != new_nlevels-1 && 1435 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 1436 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 1437 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 1438 list_remove(&dn->dn_dirty_records[txgoff], dr); 1439 list_insert_tail(&new->dt.di.dr_children, dr); 1440 dr->dr_parent = new; 1441 } 1442 } 1443 mutex_exit(&new->dt.di.dr_mtx); 1444 mutex_exit(&dn->dn_mtx); 1445 } 1446 1447 out: 1448 if (have_read) 1449 rw_downgrade(&dn->dn_struct_rwlock); 1450 } 1451 1452 void 1453 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 1454 { 1455 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1456 avl_index_t where; 1457 free_range_t *rp; 1458 free_range_t rp_tofind; 1459 uint64_t endblk = blkid + nblks; 1460 1461 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 1462 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 1463 1464 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1465 blkid, nblks, tx->tx_txg); 1466 rp_tofind.fr_blkid = blkid; 1467 rp = avl_find(tree, &rp_tofind, &where); 1468 if (rp == NULL) 1469 rp = avl_nearest(tree, where, AVL_BEFORE); 1470 if (rp == NULL) 1471 rp = avl_nearest(tree, where, AVL_AFTER); 1472 1473 while (rp && (rp->fr_blkid <= blkid + nblks)) { 1474 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 1475 free_range_t *nrp = AVL_NEXT(tree, rp); 1476 1477 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 1478 /* clear this entire range */ 1479 avl_remove(tree, rp); 1480 kmem_free(rp, sizeof (free_range_t)); 1481 } else if (blkid <= rp->fr_blkid && 1482 endblk > rp->fr_blkid && endblk < fr_endblk) { 1483 /* clear the beginning of this range */ 1484 rp->fr_blkid = endblk; 1485 rp->fr_nblks = fr_endblk - endblk; 1486 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 1487 endblk >= fr_endblk) { 1488 /* clear the end of this range */ 1489 rp->fr_nblks = blkid - rp->fr_blkid; 1490 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 1491 /* clear a chunk out of this range */ 1492 free_range_t *new_rp = 1493 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1494 1495 new_rp->fr_blkid = endblk; 1496 new_rp->fr_nblks = fr_endblk - endblk; 1497 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 1498 rp->fr_nblks = blkid - rp->fr_blkid; 1499 } 1500 /* there may be no overlap */ 1501 rp = nrp; 1502 } 1503 } 1504 1505 void 1506 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1507 { 1508 dmu_buf_impl_t *db; 1509 uint64_t blkoff, blkid, nblks; 1510 int blksz, blkshift, head, tail; 1511 int trunc = FALSE; 1512 int epbs; 1513 1514 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1515 blksz = dn->dn_datablksz; 1516 blkshift = dn->dn_datablkshift; 1517 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1518 1519 if (len == -1ULL) { 1520 len = UINT64_MAX - off; 1521 trunc = TRUE; 1522 } 1523 1524 /* 1525 * First, block align the region to free: 1526 */ 1527 if (ISP2(blksz)) { 1528 head = P2NPHASE(off, blksz); 1529 blkoff = P2PHASE(off, blksz); 1530 if ((off >> blkshift) > dn->dn_maxblkid) 1531 goto out; 1532 } else { 1533 ASSERT(dn->dn_maxblkid == 0); 1534 if (off == 0 && len >= blksz) { 1535 /* Freeing the whole block; fast-track this request */ 1536 blkid = 0; 1537 nblks = 1; 1538 goto done; 1539 } else if (off >= blksz) { 1540 /* Freeing past end-of-data */ 1541 goto out; 1542 } else { 1543 /* Freeing part of the block. */ 1544 head = blksz - off; 1545 ASSERT3U(head, >, 0); 1546 } 1547 blkoff = off; 1548 } 1549 /* zero out any partial block data at the start of the range */ 1550 if (head) { 1551 ASSERT3U(blkoff + head, ==, blksz); 1552 if (len < head) 1553 head = len; 1554 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1555 FTAG, &db) == 0) { 1556 caddr_t data; 1557 1558 /* don't dirty if it isn't on disk and isn't dirty */ 1559 if (db->db_last_dirty || 1560 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1561 rw_exit(&dn->dn_struct_rwlock); 1562 dbuf_will_dirty(db, tx); 1563 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1564 data = db->db.db_data; 1565 bzero(data + blkoff, head); 1566 } 1567 dbuf_rele(db, FTAG); 1568 } 1569 off += head; 1570 len -= head; 1571 } 1572 1573 /* If the range was less than one block, we're done */ 1574 if (len == 0) 1575 goto out; 1576 1577 /* If the remaining range is past end of file, we're done */ 1578 if ((off >> blkshift) > dn->dn_maxblkid) 1579 goto out; 1580 1581 ASSERT(ISP2(blksz)); 1582 if (trunc) 1583 tail = 0; 1584 else 1585 tail = P2PHASE(len, blksz); 1586 1587 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1588 /* zero out any partial block data at the end of the range */ 1589 if (tail) { 1590 if (len < tail) 1591 tail = len; 1592 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1593 TRUE, FTAG, &db) == 0) { 1594 /* don't dirty if not on disk and not dirty */ 1595 if (db->db_last_dirty || 1596 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1597 rw_exit(&dn->dn_struct_rwlock); 1598 dbuf_will_dirty(db, tx); 1599 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1600 bzero(db->db.db_data, tail); 1601 } 1602 dbuf_rele(db, FTAG); 1603 } 1604 len -= tail; 1605 } 1606 1607 /* If the range did not include a full block, we are done */ 1608 if (len == 0) 1609 goto out; 1610 1611 ASSERT(IS_P2ALIGNED(off, blksz)); 1612 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1613 blkid = off >> blkshift; 1614 nblks = len >> blkshift; 1615 if (trunc) 1616 nblks += 1; 1617 1618 /* 1619 * Read in and mark all the level-1 indirects dirty, 1620 * so that they will stay in memory until syncing phase. 1621 * Always dirty the first and last indirect to make sure 1622 * we dirty all the partial indirects. 1623 */ 1624 if (dn->dn_nlevels > 1) { 1625 uint64_t i, first, last; 1626 int shift = epbs + dn->dn_datablkshift; 1627 1628 first = blkid >> epbs; 1629 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1630 dbuf_will_dirty(db, tx); 1631 dbuf_rele(db, FTAG); 1632 } 1633 if (trunc) 1634 last = dn->dn_maxblkid >> epbs; 1635 else 1636 last = (blkid + nblks - 1) >> epbs; 1637 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1638 dbuf_will_dirty(db, tx); 1639 dbuf_rele(db, FTAG); 1640 } 1641 for (i = first + 1; i < last; i++) { 1642 uint64_t ibyte = i << shift; 1643 int err; 1644 1645 err = dnode_next_offset(dn, 1646 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1647 i = ibyte >> shift; 1648 if (err == ESRCH || i >= last) 1649 break; 1650 ASSERT(err == 0); 1651 db = dbuf_hold_level(dn, 1, i, FTAG); 1652 if (db) { 1653 dbuf_will_dirty(db, tx); 1654 dbuf_rele(db, FTAG); 1655 } 1656 } 1657 } 1658 done: 1659 /* 1660 * Add this range to the dnode range list. 1661 * We will finish up this free operation in the syncing phase. 1662 */ 1663 mutex_enter(&dn->dn_mtx); 1664 dnode_clear_range(dn, blkid, nblks, tx); 1665 { 1666 free_range_t *rp, *found; 1667 avl_index_t where; 1668 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1669 1670 /* Add new range to dn_ranges */ 1671 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1672 rp->fr_blkid = blkid; 1673 rp->fr_nblks = nblks; 1674 found = avl_find(tree, rp, &where); 1675 ASSERT(found == NULL); 1676 avl_insert(tree, rp, where); 1677 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1678 blkid, nblks, tx->tx_txg); 1679 } 1680 mutex_exit(&dn->dn_mtx); 1681 1682 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1683 dnode_setdirty(dn, tx); 1684 out: 1685 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1686 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1687 1688 rw_exit(&dn->dn_struct_rwlock); 1689 } 1690 1691 static boolean_t 1692 dnode_spill_freed(dnode_t *dn) 1693 { 1694 int i; 1695 1696 mutex_enter(&dn->dn_mtx); 1697 for (i = 0; i < TXG_SIZE; i++) { 1698 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1699 break; 1700 } 1701 mutex_exit(&dn->dn_mtx); 1702 return (i < TXG_SIZE); 1703 } 1704 1705 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1706 uint64_t 1707 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1708 { 1709 free_range_t range_tofind; 1710 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1711 int i; 1712 1713 if (blkid == DMU_BONUS_BLKID) 1714 return (FALSE); 1715 1716 /* 1717 * If we're in the process of opening the pool, dp will not be 1718 * set yet, but there shouldn't be anything dirty. 1719 */ 1720 if (dp == NULL) 1721 return (FALSE); 1722 1723 if (dn->dn_free_txg) 1724 return (TRUE); 1725 1726 if (blkid == DMU_SPILL_BLKID) 1727 return (dnode_spill_freed(dn)); 1728 1729 range_tofind.fr_blkid = blkid; 1730 mutex_enter(&dn->dn_mtx); 1731 for (i = 0; i < TXG_SIZE; i++) { 1732 free_range_t *range_found; 1733 avl_index_t idx; 1734 1735 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1736 if (range_found) { 1737 ASSERT(range_found->fr_nblks > 0); 1738 break; 1739 } 1740 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1741 if (range_found && 1742 range_found->fr_blkid + range_found->fr_nblks > blkid) 1743 break; 1744 } 1745 mutex_exit(&dn->dn_mtx); 1746 return (i < TXG_SIZE); 1747 } 1748 1749 /* call from syncing context when we actually write/free space for this dnode */ 1750 void 1751 dnode_diduse_space(dnode_t *dn, int64_t delta) 1752 { 1753 uint64_t space; 1754 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1755 dn, dn->dn_phys, 1756 (u_longlong_t)dn->dn_phys->dn_used, 1757 (longlong_t)delta); 1758 1759 mutex_enter(&dn->dn_mtx); 1760 space = DN_USED_BYTES(dn->dn_phys); 1761 if (delta > 0) { 1762 ASSERT3U(space + delta, >=, space); /* no overflow */ 1763 } else { 1764 ASSERT3U(space, >=, -delta); /* no underflow */ 1765 } 1766 space += delta; 1767 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1768 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1769 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1770 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1771 } else { 1772 dn->dn_phys->dn_used = space; 1773 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1774 } 1775 mutex_exit(&dn->dn_mtx); 1776 } 1777 1778 /* 1779 * Call when we think we're going to write/free space in open context. 1780 * Be conservative (ie. OK to write less than this or free more than 1781 * this, but don't write more or free less). 1782 */ 1783 void 1784 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1785 { 1786 objset_t *os = dn->dn_objset; 1787 dsl_dataset_t *ds = os->os_dsl_dataset; 1788 1789 if (space > 0) 1790 space = spa_get_asize(os->os_spa, space); 1791 1792 if (ds) 1793 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1794 1795 dmu_tx_willuse_space(tx, space); 1796 } 1797 1798 /* 1799 * This function scans a block at the indicated "level" looking for 1800 * a hole or data (depending on 'flags'). If level > 0, then we are 1801 * scanning an indirect block looking at its pointers. If level == 0, 1802 * then we are looking at a block of dnodes. If we don't find what we 1803 * are looking for in the block, we return ESRCH. Otherwise, return 1804 * with *offset pointing to the beginning (if searching forwards) or 1805 * end (if searching backwards) of the range covered by the block 1806 * pointer we matched on (or dnode). 1807 * 1808 * The basic search algorithm used below by dnode_next_offset() is to 1809 * use this function to search up the block tree (widen the search) until 1810 * we find something (i.e., we don't return ESRCH) and then search back 1811 * down the tree (narrow the search) until we reach our original search 1812 * level. 1813 */ 1814 static int 1815 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1816 int lvl, uint64_t blkfill, uint64_t txg) 1817 { 1818 dmu_buf_impl_t *db = NULL; 1819 void *data = NULL; 1820 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1821 uint64_t epb = 1ULL << epbs; 1822 uint64_t minfill, maxfill; 1823 boolean_t hole; 1824 int i, inc, error, span; 1825 1826 dprintf("probing object %llu offset %llx level %d of %u\n", 1827 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1828 1829 hole = ((flags & DNODE_FIND_HOLE) != 0); 1830 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1831 ASSERT(txg == 0 || !hole); 1832 1833 if (lvl == dn->dn_phys->dn_nlevels) { 1834 error = 0; 1835 epb = dn->dn_phys->dn_nblkptr; 1836 data = dn->dn_phys->dn_blkptr; 1837 } else { 1838 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1839 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1840 if (error) { 1841 if (error != ENOENT) 1842 return (error); 1843 if (hole) 1844 return (0); 1845 /* 1846 * This can only happen when we are searching up 1847 * the block tree for data. We don't really need to 1848 * adjust the offset, as we will just end up looking 1849 * at the pointer to this block in its parent, and its 1850 * going to be unallocated, so we will skip over it. 1851 */ 1852 return (ESRCH); 1853 } 1854 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1855 if (error) { 1856 dbuf_rele(db, FTAG); 1857 return (error); 1858 } 1859 data = db->db.db_data; 1860 } 1861 1862 if (db && txg && 1863 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1864 /* 1865 * This can only happen when we are searching up the tree 1866 * and these conditions mean that we need to keep climbing. 1867 */ 1868 error = ESRCH; 1869 } else if (lvl == 0) { 1870 dnode_phys_t *dnp = data; 1871 span = DNODE_SHIFT; 1872 ASSERT(dn->dn_type == DMU_OT_DNODE); 1873 1874 for (i = (*offset >> span) & (blkfill - 1); 1875 i >= 0 && i < blkfill; i += inc) { 1876 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1877 break; 1878 *offset += (1ULL << span) * inc; 1879 } 1880 if (i < 0 || i == blkfill) 1881 error = ESRCH; 1882 } else { 1883 blkptr_t *bp = data; 1884 uint64_t start = *offset; 1885 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1886 minfill = 0; 1887 maxfill = blkfill << ((lvl - 1) * epbs); 1888 1889 if (hole) 1890 maxfill--; 1891 else 1892 minfill++; 1893 1894 *offset = *offset >> span; 1895 for (i = BF64_GET(*offset, 0, epbs); 1896 i >= 0 && i < epb; i += inc) { 1897 if (bp[i].blk_fill >= minfill && 1898 bp[i].blk_fill <= maxfill && 1899 (hole || bp[i].blk_birth > txg)) 1900 break; 1901 if (inc > 0 || *offset > 0) 1902 *offset += inc; 1903 } 1904 *offset = *offset << span; 1905 if (inc < 0) { 1906 /* traversing backwards; position offset at the end */ 1907 ASSERT3U(*offset, <=, start); 1908 *offset = MIN(*offset + (1ULL << span) - 1, start); 1909 } else if (*offset < start) { 1910 *offset = start; 1911 } 1912 if (i < 0 || i >= epb) 1913 error = ESRCH; 1914 } 1915 1916 if (db) 1917 dbuf_rele(db, FTAG); 1918 1919 return (error); 1920 } 1921 1922 /* 1923 * Find the next hole, data, or sparse region at or after *offset. 1924 * The value 'blkfill' tells us how many items we expect to find 1925 * in an L0 data block; this value is 1 for normal objects, 1926 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1927 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1928 * 1929 * Examples: 1930 * 1931 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1932 * Finds the next/previous hole/data in a file. 1933 * Used in dmu_offset_next(). 1934 * 1935 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1936 * Finds the next free/allocated dnode an objset's meta-dnode. 1937 * Only finds objects that have new contents since txg (ie. 1938 * bonus buffer changes and content removal are ignored). 1939 * Used in dmu_object_next(). 1940 * 1941 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1942 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1943 * Used in dmu_object_alloc(). 1944 */ 1945 int 1946 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1947 int minlvl, uint64_t blkfill, uint64_t txg) 1948 { 1949 uint64_t initial_offset = *offset; 1950 int lvl, maxlvl; 1951 int error = 0; 1952 1953 if (!(flags & DNODE_FIND_HAVELOCK)) 1954 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1955 1956 if (dn->dn_phys->dn_nlevels == 0) { 1957 error = ESRCH; 1958 goto out; 1959 } 1960 1961 if (dn->dn_datablkshift == 0) { 1962 if (*offset < dn->dn_datablksz) { 1963 if (flags & DNODE_FIND_HOLE) 1964 *offset = dn->dn_datablksz; 1965 } else { 1966 error = ESRCH; 1967 } 1968 goto out; 1969 } 1970 1971 maxlvl = dn->dn_phys->dn_nlevels; 1972 1973 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1974 error = dnode_next_offset_level(dn, 1975 flags, offset, lvl, blkfill, txg); 1976 if (error != ESRCH) 1977 break; 1978 } 1979 1980 while (error == 0 && --lvl >= minlvl) { 1981 error = dnode_next_offset_level(dn, 1982 flags, offset, lvl, blkfill, txg); 1983 } 1984 1985 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1986 initial_offset < *offset : initial_offset > *offset)) 1987 error = ESRCH; 1988 out: 1989 if (!(flags & DNODE_FIND_HAVELOCK)) 1990 rw_exit(&dn->dn_struct_rwlock); 1991 1992 return (error); 1993 } 1994
Indexes created Thu May 17 00:40:56 UTC 2012
Terms of Use
|
Privacy
|
Trademarks
|
Copyright Policy
|
Site Guidelines
|
Site Map
|
Help
Your use of this web site or any of its content or software indicates your agreement to be bound by these Terms of Use.
© 2012, Oracle Corporation and/or its affiliates.