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 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/dmu.h> 32 #include <sys/dmu_impl.h> 33 #include <sys/dmu_tx.h> 34 #include <sys/dmu_objset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_dataset.h> 37 #include <sys/spa.h> 38 #include <sys/zio.h> 39 #include <sys/dmu_zfetch.h> 40 41 static int free_range_compar(const void *node1, const void *node2); 42 43 static kmem_cache_t *dnode_cache; 44 45 static dnode_phys_t dnode_phys_zero; 46 47 int zfs_default_bs = SPA_MINBLOCKSHIFT; 48 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 49 50 /* ARGSUSED */ 51 static int 52 dnode_cons(void *arg, void *unused, int kmflag) 53 { 54 int i; 55 dnode_t *dn = arg; 56 bzero(dn, sizeof (dnode_t)); 57 58 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 59 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 60 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 61 refcount_create(&dn->dn_holds); 62 refcount_create(&dn->dn_tx_holds); 63 64 for (i = 0; i < TXG_SIZE; i++) { 65 avl_create(&dn->dn_ranges[i], free_range_compar, 66 sizeof (free_range_t), 67 offsetof(struct free_range, fr_node)); 68 list_create(&dn->dn_dirty_records[i], 69 sizeof (dbuf_dirty_record_t), 70 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 71 } 72 73 list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), 74 offsetof(dmu_buf_impl_t, db_link)); 75 76 return (0); 77 } 78 79 /* ARGSUSED */ 80 static void 81 dnode_dest(void *arg, void *unused) 82 { 83 int i; 84 dnode_t *dn = arg; 85 86 rw_destroy(&dn->dn_struct_rwlock); 87 mutex_destroy(&dn->dn_mtx); 88 mutex_destroy(&dn->dn_dbufs_mtx); 89 refcount_destroy(&dn->dn_holds); 90 refcount_destroy(&dn->dn_tx_holds); 91 92 for (i = 0; i < TXG_SIZE; i++) { 93 avl_destroy(&dn->dn_ranges[i]); 94 list_destroy(&dn->dn_dirty_records[i]); 95 } 96 97 list_destroy(&dn->dn_dbufs); 98 } 99 100 void 101 dnode_init(void) 102 { 103 dnode_cache = kmem_cache_create("dnode_t", 104 sizeof (dnode_t), 105 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 106 } 107 108 void 109 dnode_fini(void) 110 { 111 kmem_cache_destroy(dnode_cache); 112 } 113 114 115 #ifdef ZFS_DEBUG 116 void 117 dnode_verify(dnode_t *dn) 118 { 119 int drop_struct_lock = FALSE; 120 121 ASSERT(dn->dn_phys); 122 ASSERT(dn->dn_objset); 123 124 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 125 126 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 127 return; 128 129 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 130 rw_enter(&dn->dn_struct_rwlock, RW_READER); 131 drop_struct_lock = TRUE; 132 } 133 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 134 int i; 135 ASSERT3U(dn->dn_indblkshift, >=, 0); 136 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 137 if (dn->dn_datablkshift) { 138 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 139 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 140 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 141 } 142 ASSERT3U(dn->dn_nlevels, <=, 30); 143 ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); 144 ASSERT3U(dn->dn_nblkptr, >=, 1); 145 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 146 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 147 ASSERT3U(dn->dn_datablksz, ==, 148 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 149 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 150 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 151 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 152 for (i = 0; i < TXG_SIZE; i++) { 153 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 154 } 155 } 156 if (dn->dn_phys->dn_type != DMU_OT_NONE) 157 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 158 ASSERT(dn->dn_object == DMU_META_DNODE_OBJECT || dn->dn_dbuf != NULL); 159 if (dn->dn_dbuf != NULL) { 160 ASSERT3P(dn->dn_phys, ==, 161 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 162 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 163 } 164 if (drop_struct_lock) 165 rw_exit(&dn->dn_struct_rwlock); 166 } 167 #endif 168 169 void 170 dnode_byteswap(dnode_phys_t *dnp) 171 { 172 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 173 int i; 174 175 if (dnp->dn_type == DMU_OT_NONE) { 176 bzero(dnp, sizeof (dnode_phys_t)); 177 return; 178 } 179 180 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 181 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 182 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 183 dnp->dn_used = BSWAP_64(dnp->dn_used); 184 185 /* 186 * dn_nblkptr is only one byte, so it's OK to read it in either 187 * byte order. We can't read dn_bouslen. 188 */ 189 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 190 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 191 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 192 buf64[i] = BSWAP_64(buf64[i]); 193 194 /* 195 * OK to check dn_bonuslen for zero, because it won't matter if 196 * we have the wrong byte order. This is necessary because the 197 * dnode dnode is smaller than a regular dnode. 198 */ 199 if (dnp->dn_bonuslen != 0) { 200 /* 201 * Note that the bonus length calculated here may be 202 * longer than the actual bonus buffer. This is because 203 * we always put the bonus buffer after the last block 204 * pointer (instead of packing it against the end of the 205 * dnode buffer). 206 */ 207 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 208 size_t len = DN_MAX_BONUSLEN - off; 209 ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); 210 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 211 } 212 } 213 214 void 215 dnode_buf_byteswap(void *vbuf, size_t size) 216 { 217 dnode_phys_t *buf = vbuf; 218 int i; 219 220 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 221 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 222 223 size >>= DNODE_SHIFT; 224 for (i = 0; i < size; i++) { 225 dnode_byteswap(buf); 226 buf++; 227 } 228 } 229 230 static int 231 free_range_compar(const void *node1, const void *node2) 232 { 233 const free_range_t *rp1 = node1; 234 const free_range_t *rp2 = node2; 235 236 if (rp1->fr_blkid < rp2->fr_blkid) 237 return (-1); 238 else if (rp1->fr_blkid > rp2->fr_blkid) 239 return (1); 240 else return (0); 241 } 242 243 static void 244 dnode_setdblksz(dnode_t *dn, int size) 245 { 246 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 247 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 248 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 249 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 250 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 251 dn->dn_datablksz = size; 252 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 253 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 254 } 255 256 static dnode_t * 257 dnode_create(objset_impl_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 258 uint64_t object) 259 { 260 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 261 (void) dnode_cons(dn, NULL, 0); /* XXX */ 262 263 dn->dn_objset = os; 264 dn->dn_object = object; 265 dn->dn_dbuf = db; 266 dn->dn_phys = dnp; 267 268 if (dnp->dn_datablkszsec) 269 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 270 dn->dn_indblkshift = dnp->dn_indblkshift; 271 dn->dn_nlevels = dnp->dn_nlevels; 272 dn->dn_type = dnp->dn_type; 273 dn->dn_nblkptr = dnp->dn_nblkptr; 274 dn->dn_checksum = dnp->dn_checksum; 275 dn->dn_compress = dnp->dn_compress; 276 dn->dn_bonustype = dnp->dn_bonustype; 277 dn->dn_bonuslen = dnp->dn_bonuslen; 278 dn->dn_maxblkid = dnp->dn_maxblkid; 279 280 dmu_zfetch_init(&dn->dn_zfetch, dn); 281 282 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 283 mutex_enter(&os->os_lock); 284 list_insert_head(&os->os_dnodes, dn); 285 mutex_exit(&os->os_lock); 286 287 return (dn); 288 } 289 290 static void 291 dnode_destroy(dnode_t *dn) 292 { 293 objset_impl_t *os = dn->dn_objset; 294 295 #ifdef ZFS_DEBUG 296 int i; 297 298 for (i = 0; i < TXG_SIZE; i++) { 299 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 300 ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); 301 ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); 302 } 303 ASSERT(NULL == list_head(&dn->dn_dbufs)); 304 #endif 305 306 mutex_enter(&os->os_lock); 307 list_remove(&os->os_dnodes, dn); 308 mutex_exit(&os->os_lock); 309 310 if (dn->dn_dirtyctx_firstset) { 311 kmem_free(dn->dn_dirtyctx_firstset, 1); 312 dn->dn_dirtyctx_firstset = NULL; 313 } 314 dmu_zfetch_rele(&dn->dn_zfetch); 315 if (dn->dn_bonus) { 316 mutex_enter(&dn->dn_bonus->db_mtx); 317 dbuf_evict(dn->dn_bonus); 318 dn->dn_bonus = NULL; 319 } 320 kmem_cache_free(dnode_cache, dn); 321 } 322 323 void 324 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 325 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 326 { 327 int i; 328 329 if (blocksize == 0) 330 blocksize = 1 << zfs_default_bs; 331 else if (blocksize > SPA_MAXBLOCKSIZE) 332 blocksize = SPA_MAXBLOCKSIZE; 333 else 334 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 335 336 if (ibs == 0) 337 ibs = zfs_default_ibs; 338 339 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 340 341 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 342 dn->dn_object, tx->tx_txg, blocksize, ibs); 343 344 ASSERT(dn->dn_type == DMU_OT_NONE); 345 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 346 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 347 ASSERT(ot != DMU_OT_NONE); 348 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 349 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 350 (bonustype != DMU_OT_NONE && bonuslen != 0)); 351 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 352 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 353 ASSERT(dn->dn_type == DMU_OT_NONE); 354 ASSERT3U(dn->dn_maxblkid, ==, 0); 355 ASSERT3U(dn->dn_allocated_txg, ==, 0); 356 ASSERT3U(dn->dn_assigned_txg, ==, 0); 357 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 358 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 359 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 360 361 for (i = 0; i < TXG_SIZE; i++) { 362 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 363 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 364 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 365 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 366 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 367 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 368 } 369 370 dn->dn_type = ot; 371 dnode_setdblksz(dn, blocksize); 372 dn->dn_indblkshift = ibs; 373 dn->dn_nlevels = 1; 374 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 375 dn->dn_bonustype = bonustype; 376 dn->dn_bonuslen = bonuslen; 377 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 378 dn->dn_compress = ZIO_COMPRESS_INHERIT; 379 dn->dn_dirtyctx = 0; 380 381 dn->dn_free_txg = 0; 382 if (dn->dn_dirtyctx_firstset) { 383 kmem_free(dn->dn_dirtyctx_firstset, 1); 384 dn->dn_dirtyctx_firstset = NULL; 385 } 386 387 dn->dn_allocated_txg = tx->tx_txg; 388 389 dnode_setdirty(dn, tx); 390 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 391 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 392 } 393 394 void 395 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 396 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 397 { 398 int i; 399 dmu_buf_impl_t *db = NULL; 400 401 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 402 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 403 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 404 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 405 ASSERT(tx->tx_txg != 0); 406 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 407 (bonustype != DMU_OT_NONE && bonuslen != 0)); 408 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 409 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 410 411 for (i = 0; i < TXG_SIZE; i++) 412 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 413 414 /* clean up any unreferenced dbufs */ 415 (void) dnode_evict_dbufs(dn, 0); 416 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 417 418 /* 419 * XXX I should really have a generation number to tell if we 420 * need to do this... 421 */ 422 if (blocksize != dn->dn_datablksz || 423 dn->dn_bonustype != bonustype || dn->dn_bonuslen != bonuslen) { 424 /* free all old data */ 425 dnode_free_range(dn, 0, -1ULL, tx); 426 } 427 428 /* change blocksize */ 429 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 430 if (blocksize != dn->dn_datablksz && 431 (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 432 list_head(&dn->dn_dbufs) != NULL)) { 433 db = dbuf_hold(dn, 0, FTAG); 434 dbuf_new_size(db, blocksize, tx); 435 } 436 dnode_setdblksz(dn, blocksize); 437 dnode_setdirty(dn, tx); 438 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 439 rw_exit(&dn->dn_struct_rwlock); 440 if (db) { 441 dbuf_rele(db, FTAG); 442 db = NULL; 443 } 444 445 /* change type */ 446 dn->dn_type = ot; 447 448 if (dn->dn_bonuslen != bonuslen) { 449 /* change bonus size */ 450 if (bonuslen == 0) 451 bonuslen = 1; /* XXX */ 452 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 453 if (dn->dn_bonus == NULL) 454 dn->dn_bonus = dbuf_create_bonus(dn); 455 db = dn->dn_bonus; 456 rw_exit(&dn->dn_struct_rwlock); 457 if (refcount_add(&db->db_holds, FTAG) == 1) 458 dnode_add_ref(dn, db); 459 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED)); 460 mutex_enter(&db->db_mtx); 461 ASSERT3U(db->db.db_size, ==, dn->dn_bonuslen); 462 ASSERT(db->db.db_data != NULL); 463 db->db.db_size = bonuslen; 464 mutex_exit(&db->db_mtx); 465 (void) dbuf_dirty(db, tx); 466 } 467 468 /* change bonus size and type */ 469 mutex_enter(&dn->dn_mtx); 470 dn->dn_bonustype = bonustype; 471 dn->dn_bonuslen = bonuslen; 472 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 473 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 474 dn->dn_compress = ZIO_COMPRESS_INHERIT; 475 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 476 477 /* 478 * NB: we have to do the dbuf_rele after we've changed the 479 * dn_bonuslen, for the sake of dbuf_verify(). 480 */ 481 if (db) 482 dbuf_rele(db, FTAG); 483 484 dn->dn_allocated_txg = tx->tx_txg; 485 mutex_exit(&dn->dn_mtx); 486 } 487 488 void 489 dnode_special_close(dnode_t *dn) 490 { 491 /* 492 * Wait for final references to the dnode to clear. This can 493 * only happen if the arc is asyncronously evicting state that 494 * has a hold on this dnode while we are trying to evict this 495 * dnode. 496 */ 497 while (refcount_count(&dn->dn_holds) > 0) 498 delay(1); 499 dnode_destroy(dn); 500 } 501 502 dnode_t * 503 dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 504 { 505 dnode_t *dn = dnode_create(os, dnp, NULL, object); 506 DNODE_VERIFY(dn); 507 return (dn); 508 } 509 510 static void 511 dnode_buf_pageout(dmu_buf_t *db, void *arg) 512 { 513 dnode_t **children_dnodes = arg; 514 int i; 515 int epb = db->db_size >> DNODE_SHIFT; 516 517 for (i = 0; i < epb; i++) { 518 dnode_t *dn = children_dnodes[i]; 519 int n; 520 521 if (dn == NULL) 522 continue; 523 #ifdef ZFS_DEBUG 524 /* 525 * If there are holds on this dnode, then there should 526 * be holds on the dnode's containing dbuf as well; thus 527 * it wouldn't be eligable for eviction and this function 528 * would not have been called. 529 */ 530 ASSERT(refcount_is_zero(&dn->dn_holds)); 531 ASSERT(list_head(&dn->dn_dbufs) == NULL); 532 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 533 534 for (n = 0; n < TXG_SIZE; n++) 535 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 536 #endif 537 children_dnodes[i] = NULL; 538 dnode_destroy(dn); 539 } 540 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 541 } 542 543 /* 544 * errors: 545 * EINVAL - invalid object number. 546 * EIO - i/o error. 547 * succeeds even for free dnodes. 548 */ 549 int 550 dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 551 void *tag, dnode_t **dnp) 552 { 553 int epb, idx, err; 554 int drop_struct_lock = FALSE; 555 int type; 556 uint64_t blk; 557 dnode_t *mdn, *dn; 558 dmu_buf_impl_t *db; 559 dnode_t **children_dnodes; 560 561 if (object == 0 || object >= DN_MAX_OBJECT) 562 return (EINVAL); 563 564 mdn = os->os_meta_dnode; 565 566 DNODE_VERIFY(mdn); 567 568 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 569 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 570 drop_struct_lock = TRUE; 571 } 572 573 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 574 575 db = dbuf_hold(mdn, blk, FTAG); 576 if (drop_struct_lock) 577 rw_exit(&mdn->dn_struct_rwlock); 578 if (db == NULL) 579 return (EIO); 580 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 581 if (err) { 582 dbuf_rele(db, FTAG); 583 return (err); 584 } 585 586 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 587 epb = db->db.db_size >> DNODE_SHIFT; 588 589 idx = object & (epb-1); 590 591 children_dnodes = dmu_buf_get_user(&db->db); 592 if (children_dnodes == NULL) { 593 dnode_t **winner; 594 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 595 KM_SLEEP); 596 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 597 dnode_buf_pageout)) { 598 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 599 children_dnodes = winner; 600 } 601 } 602 603 if ((dn = children_dnodes[idx]) == NULL) { 604 dnode_t *winner; 605 dn = dnode_create(os, (dnode_phys_t *)db->db.db_data+idx, 606 db, object); 607 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 608 if (winner != NULL) { 609 dnode_destroy(dn); 610 dn = winner; 611 } 612 } 613 614 mutex_enter(&dn->dn_mtx); 615 type = dn->dn_type; 616 if (dn->dn_free_txg || 617 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 618 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 619 mutex_exit(&dn->dn_mtx); 620 dbuf_rele(db, FTAG); 621 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 622 } 623 mutex_exit(&dn->dn_mtx); 624 625 if (refcount_add(&dn->dn_holds, tag) == 1) 626 dbuf_add_ref(db, dn); 627 628 DNODE_VERIFY(dn); 629 ASSERT3P(dn->dn_dbuf, ==, db); 630 ASSERT3U(dn->dn_object, ==, object); 631 dbuf_rele(db, FTAG); 632 633 *dnp = dn; 634 return (0); 635 } 636 637 /* 638 * Return held dnode if the object is allocated, NULL if not. 639 */ 640 int 641 dnode_hold(objset_impl_t *os, uint64_t object, void *tag, dnode_t **dnp) 642 { 643 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 644 } 645 646 void 647 dnode_add_ref(dnode_t *dn, void *tag) 648 { 649 ASSERT(refcount_count(&dn->dn_holds) > 0); 650 (void) refcount_add(&dn->dn_holds, tag); 651 } 652 653 void 654 dnode_rele(dnode_t *dn, void *tag) 655 { 656 uint64_t refs; 657 658 refs = refcount_remove(&dn->dn_holds, tag); 659 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 660 if (refs == 0 && dn->dn_dbuf) 661 dbuf_rele(dn->dn_dbuf, dn); 662 } 663 664 void 665 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 666 { 667 objset_impl_t *os = dn->dn_objset; 668 uint64_t txg = tx->tx_txg; 669 670 if (dn->dn_object == DMU_META_DNODE_OBJECT) 671 return; 672 673 DNODE_VERIFY(dn); 674 675 #ifdef ZFS_DEBUG 676 mutex_enter(&dn->dn_mtx); 677 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 678 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 679 mutex_exit(&dn->dn_mtx); 680 #endif 681 682 mutex_enter(&os->os_lock); 683 684 /* 685 * If we are already marked dirty, we're done. 686 */ 687 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 688 mutex_exit(&os->os_lock); 689 return; 690 } 691 692 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 693 ASSERT(dn->dn_datablksz != 0); 694 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 695 696 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 697 dn->dn_object, txg); 698 699 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 700 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 701 } else { 702 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 703 } 704 705 mutex_exit(&os->os_lock); 706 707 /* 708 * The dnode maintains a hold on its containing dbuf as 709 * long as there are holds on it. Each instantiated child 710 * dbuf maintaines a hold on the dnode. When the last child 711 * drops its hold, the dnode will drop its hold on the 712 * containing dbuf. We add a "dirty hold" here so that the 713 * dnode will hang around after we finish processing its 714 * children. 715 */ 716 dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg); 717 718 (void) dbuf_dirty(dn->dn_dbuf, tx); 719 720 dsl_dataset_dirty(os->os_dsl_dataset, tx); 721 } 722 723 void 724 dnode_free(dnode_t *dn, dmu_tx_t *tx) 725 { 726 int txgoff = tx->tx_txg & TXG_MASK; 727 728 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 729 730 /* we should be the only holder... hopefully */ 731 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 732 733 mutex_enter(&dn->dn_mtx); 734 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 735 mutex_exit(&dn->dn_mtx); 736 return; 737 } 738 dn->dn_free_txg = tx->tx_txg; 739 mutex_exit(&dn->dn_mtx); 740 741 /* 742 * If the dnode is already dirty, it needs to be moved from 743 * the dirty list to the free list. 744 */ 745 mutex_enter(&dn->dn_objset->os_lock); 746 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 747 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 748 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 749 mutex_exit(&dn->dn_objset->os_lock); 750 } else { 751 mutex_exit(&dn->dn_objset->os_lock); 752 dnode_setdirty(dn, tx); 753 } 754 } 755 756 /* 757 * Try to change the block size for the indicated dnode. This can only 758 * succeed if there are no blocks allocated or dirty beyond first block 759 */ 760 int 761 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 762 { 763 dmu_buf_impl_t *db, *db_next; 764 int have_db0 = FALSE; 765 766 if (size == 0) 767 size = SPA_MINBLOCKSIZE; 768 if (size > SPA_MAXBLOCKSIZE) 769 size = SPA_MAXBLOCKSIZE; 770 else 771 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 772 773 if (ibs == dn->dn_indblkshift) 774 ibs = 0; 775 776 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 777 return (0); 778 779 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 780 781 /* Check for any allocated blocks beyond the first */ 782 if (dn->dn_phys->dn_maxblkid != 0) 783 goto fail; 784 785 mutex_enter(&dn->dn_dbufs_mtx); 786 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 787 db_next = list_next(&dn->dn_dbufs, db); 788 789 if (db->db_blkid == 0) { 790 have_db0 = TRUE; 791 } else if (db->db_blkid != DB_BONUS_BLKID) { 792 mutex_exit(&dn->dn_dbufs_mtx); 793 goto fail; 794 } 795 } 796 mutex_exit(&dn->dn_dbufs_mtx); 797 798 if (ibs && dn->dn_nlevels != 1) 799 goto fail; 800 801 db = NULL; 802 if (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || have_db0) { 803 /* obtain the old block */ 804 db = dbuf_hold(dn, 0, FTAG); 805 dbuf_new_size(db, size, tx); 806 } 807 808 dnode_setdblksz(dn, size); 809 dnode_setdirty(dn, tx); 810 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 811 if (ibs) { 812 dn->dn_indblkshift = ibs; 813 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 814 } 815 816 if (db) 817 dbuf_rele(db, FTAG); 818 819 rw_exit(&dn->dn_struct_rwlock); 820 return (0); 821 822 fail: 823 rw_exit(&dn->dn_struct_rwlock); 824 return (ENOTSUP); 825 } 826 827 void 828 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx) 829 { 830 uint64_t txgoff = tx->tx_txg & TXG_MASK; 831 int drop_struct_lock = FALSE; 832 int epbs, new_nlevels; 833 uint64_t sz; 834 835 ASSERT(blkid != DB_BONUS_BLKID); 836 837 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 838 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 839 drop_struct_lock = TRUE; 840 } 841 842 if (blkid <= dn->dn_maxblkid) 843 goto out; 844 845 dn->dn_maxblkid = blkid; 846 847 /* 848 * Compute the number of levels necessary to support the new maxblkid. 849 */ 850 new_nlevels = 1; 851 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 852 for (sz = dn->dn_nblkptr; 853 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 854 new_nlevels++; 855 856 if (new_nlevels > dn->dn_nlevels) { 857 int old_nlevels = dn->dn_nlevels; 858 dmu_buf_impl_t *db; 859 list_t *list; 860 dbuf_dirty_record_t *new, *dr, *dr_next; 861 862 dn->dn_nlevels = new_nlevels; 863 864 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 865 dn->dn_next_nlevels[txgoff] = new_nlevels; 866 867 /* dirty the left indirects */ 868 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 869 new = dbuf_dirty(db, tx); 870 dbuf_rele(db, FTAG); 871 872 /* transfer the dirty records to the new indirect */ 873 mutex_enter(&dn->dn_mtx); 874 mutex_enter(&new->dt.di.dr_mtx); 875 list = &dn->dn_dirty_records[txgoff]; 876 for (dr = list_head(list); dr; dr = dr_next) { 877 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 878 if (dr->dr_dbuf->db_level != new_nlevels-1 && 879 dr->dr_dbuf->db_blkid != DB_BONUS_BLKID) { 880 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 881 list_remove(&dn->dn_dirty_records[txgoff], dr); 882 list_insert_tail(&new->dt.di.dr_children, dr); 883 dr->dr_parent = new; 884 } 885 } 886 mutex_exit(&new->dt.di.dr_mtx); 887 mutex_exit(&dn->dn_mtx); 888 } 889 890 out: 891 if (drop_struct_lock) 892 rw_exit(&dn->dn_struct_rwlock); 893 } 894 895 void 896 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 897 { 898 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 899 avl_index_t where; 900 free_range_t *rp; 901 free_range_t rp_tofind; 902 uint64_t endblk = blkid + nblks; 903 904 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 905 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 906 907 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 908 blkid, nblks, tx->tx_txg); 909 rp_tofind.fr_blkid = blkid; 910 rp = avl_find(tree, &rp_tofind, &where); 911 if (rp == NULL) 912 rp = avl_nearest(tree, where, AVL_BEFORE); 913 if (rp == NULL) 914 rp = avl_nearest(tree, where, AVL_AFTER); 915 916 while (rp && (rp->fr_blkid <= blkid + nblks)) { 917 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 918 free_range_t *nrp = AVL_NEXT(tree, rp); 919 920 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 921 /* clear this entire range */ 922 avl_remove(tree, rp); 923 kmem_free(rp, sizeof (free_range_t)); 924 } else if (blkid <= rp->fr_blkid && 925 endblk > rp->fr_blkid && endblk < fr_endblk) { 926 /* clear the beginning of this range */ 927 rp->fr_blkid = endblk; 928 rp->fr_nblks = fr_endblk - endblk; 929 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 930 endblk >= fr_endblk) { 931 /* clear the end of this range */ 932 rp->fr_nblks = blkid - rp->fr_blkid; 933 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 934 /* clear a chunk out of this range */ 935 free_range_t *new_rp = 936 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 937 938 new_rp->fr_blkid = endblk; 939 new_rp->fr_nblks = fr_endblk - endblk; 940 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 941 rp->fr_nblks = blkid - rp->fr_blkid; 942 } 943 /* there may be no overlap */ 944 rp = nrp; 945 } 946 } 947 948 void 949 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 950 { 951 dmu_buf_impl_t *db; 952 uint64_t blkoff, blkid, nblks; 953 int blksz, head; 954 int trunc = FALSE; 955 956 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 957 blksz = dn->dn_datablksz; 958 959 /* If the range is past the end of the file, this is a no-op */ 960 if (off >= blksz * (dn->dn_maxblkid+1)) 961 goto out; 962 if (len == -1ULL) { 963 len = UINT64_MAX - off; 964 trunc = TRUE; 965 } 966 967 /* 968 * First, block align the region to free: 969 */ 970 if (ISP2(blksz)) { 971 head = P2NPHASE(off, blksz); 972 blkoff = P2PHASE(off, blksz); 973 } else { 974 ASSERT(dn->dn_maxblkid == 0); 975 if (off == 0 && len >= blksz) { 976 /* Freeing the whole block; don't do any head. */ 977 head = 0; 978 } else { 979 /* Freeing part of the block. */ 980 head = blksz - off; 981 ASSERT3U(head, >, 0); 982 } 983 blkoff = off; 984 } 985 /* zero out any partial block data at the start of the range */ 986 if (head) { 987 ASSERT3U(blkoff + head, ==, blksz); 988 if (len < head) 989 head = len; 990 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 991 FTAG, &db) == 0) { 992 caddr_t data; 993 994 /* don't dirty if it isn't on disk and isn't dirty */ 995 if (db->db_last_dirty || 996 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 997 rw_exit(&dn->dn_struct_rwlock); 998 dbuf_will_dirty(db, tx); 999 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1000 data = db->db.db_data; 1001 bzero(data + blkoff, head); 1002 } 1003 dbuf_rele(db, FTAG); 1004 } 1005 off += head; 1006 len -= head; 1007 } 1008 1009 /* If the range was less than one block, we're done */ 1010 if (len == 0 || off >= blksz * (dn->dn_maxblkid+1)) 1011 goto out; 1012 1013 if (!ISP2(blksz)) { 1014 /* 1015 * They are freeing the whole block of a 1016 * non-power-of-two blocksize file. Skip all the messy 1017 * math. 1018 */ 1019 ASSERT3U(off, ==, 0); 1020 ASSERT3U(len, >=, blksz); 1021 blkid = 0; 1022 nblks = 1; 1023 } else { 1024 int tail; 1025 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1026 int blkshift = dn->dn_datablkshift; 1027 1028 /* If the remaining range is past end of file, we're done */ 1029 if (off > dn->dn_maxblkid << blkshift) 1030 goto out; 1031 1032 if (off + len == UINT64_MAX) 1033 tail = 0; 1034 else 1035 tail = P2PHASE(len, blksz); 1036 1037 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1038 /* zero out any partial block data at the end of the range */ 1039 if (tail) { 1040 if (len < tail) 1041 tail = len; 1042 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1043 TRUE, FTAG, &db) == 0) { 1044 /* don't dirty if not on disk and not dirty */ 1045 if (db->db_last_dirty || 1046 (db->db_blkptr && 1047 !BP_IS_HOLE(db->db_blkptr))) { 1048 rw_exit(&dn->dn_struct_rwlock); 1049 dbuf_will_dirty(db, tx); 1050 rw_enter(&dn->dn_struct_rwlock, 1051 RW_WRITER); 1052 bzero(db->db.db_data, tail); 1053 } 1054 dbuf_rele(db, FTAG); 1055 } 1056 len -= tail; 1057 } 1058 /* If the range did not include a full block, we are done */ 1059 if (len == 0) 1060 goto out; 1061 1062 /* dirty the left indirects */ 1063 if (dn->dn_nlevels > 1 && off != 0) { 1064 db = dbuf_hold_level(dn, 1, 1065 (off - head) >> (blkshift + epbs), FTAG); 1066 dbuf_will_dirty(db, tx); 1067 dbuf_rele(db, FTAG); 1068 } 1069 1070 /* dirty the right indirects */ 1071 if (dn->dn_nlevels > 1 && !trunc) { 1072 db = dbuf_hold_level(dn, 1, 1073 (off + len + tail - 1) >> (blkshift + epbs), FTAG); 1074 dbuf_will_dirty(db, tx); 1075 dbuf_rele(db, FTAG); 1076 } 1077 1078 /* 1079 * Finally, add this range to the dnode range list, we 1080 * will finish up this free operation in the syncing phase. 1081 */ 1082 ASSERT(IS_P2ALIGNED(off, 1<<blkshift)); 1083 ASSERT(off + len == UINT64_MAX || 1084 IS_P2ALIGNED(len, 1<<blkshift)); 1085 blkid = off >> blkshift; 1086 nblks = len >> blkshift; 1087 1088 if (trunc) 1089 dn->dn_maxblkid = (blkid ? blkid - 1 : 0); 1090 } 1091 1092 mutex_enter(&dn->dn_mtx); 1093 dnode_clear_range(dn, blkid, nblks, tx); 1094 { 1095 free_range_t *rp, *found; 1096 avl_index_t where; 1097 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1098 1099 /* Add new range to dn_ranges */ 1100 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1101 rp->fr_blkid = blkid; 1102 rp->fr_nblks = nblks; 1103 found = avl_find(tree, rp, &where); 1104 ASSERT(found == NULL); 1105 avl_insert(tree, rp, where); 1106 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1107 blkid, nblks, tx->tx_txg); 1108 } 1109 mutex_exit(&dn->dn_mtx); 1110 1111 dbuf_free_range(dn, blkid, nblks, tx); 1112 dnode_setdirty(dn, tx); 1113 out: 1114 rw_exit(&dn->dn_struct_rwlock); 1115 } 1116 1117 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1118 uint64_t 1119 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1120 { 1121 free_range_t range_tofind; 1122 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1123 int i; 1124 1125 if (blkid == DB_BONUS_BLKID) 1126 return (FALSE); 1127 1128 /* 1129 * If we're in the process of opening the pool, dp will not be 1130 * set yet, but there shouldn't be anything dirty. 1131 */ 1132 if (dp == NULL) 1133 return (FALSE); 1134 1135 if (dn->dn_free_txg) 1136 return (TRUE); 1137 1138 /* 1139 * If dn_datablkshift is not set, then there's only a single 1140 * block, in which case there will never be a free range so it 1141 * won't matter. 1142 */ 1143 range_tofind.fr_blkid = blkid; 1144 mutex_enter(&dn->dn_mtx); 1145 for (i = 0; i < TXG_SIZE; i++) { 1146 free_range_t *range_found; 1147 avl_index_t idx; 1148 1149 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1150 if (range_found) { 1151 ASSERT(range_found->fr_nblks > 0); 1152 break; 1153 } 1154 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1155 if (range_found && 1156 range_found->fr_blkid + range_found->fr_nblks > blkid) 1157 break; 1158 } 1159 mutex_exit(&dn->dn_mtx); 1160 return (i < TXG_SIZE); 1161 } 1162 1163 /* call from syncing context when we actually write/free space for this dnode */ 1164 void 1165 dnode_diduse_space(dnode_t *dn, int64_t delta) 1166 { 1167 uint64_t space; 1168 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1169 dn, dn->dn_phys, 1170 (u_longlong_t)dn->dn_phys->dn_used, 1171 (longlong_t)delta); 1172 1173 mutex_enter(&dn->dn_mtx); 1174 space = DN_USED_BYTES(dn->dn_phys); 1175 if (delta > 0) { 1176 ASSERT3U(space + delta, >=, space); /* no overflow */ 1177 } else { 1178 ASSERT3U(space, >=, -delta); /* no underflow */ 1179 } 1180 space += delta; 1181 if (spa_version(dn->dn_objset->os_spa) < ZFS_VERSION_DNODE_BYTES) { 1182 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1183 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1184 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1185 } else { 1186 dn->dn_phys->dn_used = space; 1187 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1188 } 1189 mutex_exit(&dn->dn_mtx); 1190 } 1191 1192 /* 1193 * Call when we think we're going to write/free space in open context. 1194 * Be conservative (ie. OK to write less than this or free more than 1195 * this, but don't write more or free less). 1196 */ 1197 void 1198 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1199 { 1200 objset_impl_t *os = dn->dn_objset; 1201 dsl_dataset_t *ds = os->os_dsl_dataset; 1202 1203 if (space > 0) 1204 space = spa_get_asize(os->os_spa, space); 1205 1206 if (ds) 1207 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1208 1209 dmu_tx_willuse_space(tx, space); 1210 } 1211 1212 static int 1213 dnode_next_offset_level(dnode_t *dn, boolean_t hole, uint64_t *offset, 1214 int lvl, uint64_t blkfill, uint64_t txg) 1215 { 1216 dmu_buf_impl_t *db = NULL; 1217 void *data = NULL; 1218 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1219 uint64_t epb = 1ULL << epbs; 1220 uint64_t minfill, maxfill; 1221 int i, error, span; 1222 1223 dprintf("probing object %llu offset %llx level %d of %u\n", 1224 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1225 1226 if (lvl == dn->dn_phys->dn_nlevels) { 1227 error = 0; 1228 epb = dn->dn_phys->dn_nblkptr; 1229 data = dn->dn_phys->dn_blkptr; 1230 } else { 1231 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1232 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1233 if (error) { 1234 if (error == ENOENT) 1235 return (hole ? 0 : ESRCH); 1236 return (error); 1237 } 1238 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1239 if (error) { 1240 dbuf_rele(db, FTAG); 1241 return (error); 1242 } 1243 data = db->db.db_data; 1244 } 1245 1246 if (db && txg && 1247 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1248 error = ESRCH; 1249 } else if (lvl == 0) { 1250 dnode_phys_t *dnp = data; 1251 span = DNODE_SHIFT; 1252 ASSERT(dn->dn_type == DMU_OT_DNODE); 1253 1254 for (i = (*offset >> span) & (blkfill - 1); i < blkfill; i++) { 1255 boolean_t newcontents = B_TRUE; 1256 if (txg) { 1257 int j; 1258 newcontents = B_FALSE; 1259 for (j = 0; j < dnp[i].dn_nblkptr; j++) { 1260 if (dnp[i].dn_blkptr[j].blk_birth > txg) 1261 newcontents = B_TRUE; 1262 } 1263 } 1264 if (!dnp[i].dn_type == hole && newcontents) 1265 break; 1266 *offset += 1ULL << span; 1267 } 1268 if (i == blkfill) 1269 error = ESRCH; 1270 } else { 1271 blkptr_t *bp = data; 1272 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1273 minfill = 0; 1274 maxfill = blkfill << ((lvl - 1) * epbs); 1275 1276 if (hole) 1277 maxfill--; 1278 else 1279 minfill++; 1280 1281 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1282 i < epb; i++) { 1283 if (bp[i].blk_fill >= minfill && 1284 bp[i].blk_fill <= maxfill && 1285 bp[i].blk_birth > txg) 1286 break; 1287 *offset += 1ULL << span; 1288 } 1289 if (i >= epb) 1290 error = ESRCH; 1291 } 1292 1293 if (db) 1294 dbuf_rele(db, FTAG); 1295 1296 return (error); 1297 } 1298 1299 /* 1300 * Find the next hole, data, or sparse region at or after *offset. 1301 * The value 'blkfill' tells us how many items we expect to find 1302 * in an L0 data block; this value is 1 for normal objects, 1303 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1304 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1305 * 1306 * Examples: 1307 * 1308 * dnode_next_offset(dn, hole, offset, 1, 1, 0); 1309 * Finds the next hole/data in a file. 1310 * Used in dmu_offset_next(). 1311 * 1312 * dnode_next_offset(mdn, hole, offset, 0, DNODES_PER_BLOCK, txg); 1313 * Finds the next free/allocated dnode an objset's meta-dnode. 1314 * Only finds objects that have new contents since txg (ie. 1315 * bonus buffer changes and content removal are ignored). 1316 * Used in dmu_object_next(). 1317 * 1318 * dnode_next_offset(mdn, TRUE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1319 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1320 * Used in dmu_object_alloc(). 1321 */ 1322 int 1323 dnode_next_offset(dnode_t *dn, boolean_t hole, uint64_t *offset, 1324 int minlvl, uint64_t blkfill, uint64_t txg) 1325 { 1326 int lvl, maxlvl; 1327 int error = 0; 1328 uint64_t initial_offset = *offset; 1329 1330 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1331 1332 if (dn->dn_phys->dn_nlevels == 0) { 1333 rw_exit(&dn->dn_struct_rwlock); 1334 return (ESRCH); 1335 } 1336 1337 if (dn->dn_datablkshift == 0) { 1338 if (*offset < dn->dn_datablksz) { 1339 if (hole) 1340 *offset = dn->dn_datablksz; 1341 } else { 1342 error = ESRCH; 1343 } 1344 rw_exit(&dn->dn_struct_rwlock); 1345 return (error); 1346 } 1347 1348 maxlvl = dn->dn_phys->dn_nlevels; 1349 1350 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1351 error = dnode_next_offset_level(dn, 1352 hole, offset, lvl, blkfill, txg); 1353 if (error != ESRCH) 1354 break; 1355 } 1356 1357 while (--lvl >= minlvl && error == 0) { 1358 error = dnode_next_offset_level(dn, 1359 hole, offset, lvl, blkfill, txg); 1360 } 1361 1362 rw_exit(&dn->dn_struct_rwlock); 1363 1364 if (error == 0 && initial_offset > *offset) 1365 error = ESRCH; 1366 1367 return (error); 1368 } 1369