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 2006 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_dbufs[i], 69 sizeof (dmu_buf_impl_t), 70 offsetof(dmu_buf_impl_t, db_dirty_node[i])); 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_dbufs[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_type = BSWAP_8(dnp->dn_type); 181 dnp->dn_indblkshift = BSWAP_8(dnp->dn_indblkshift); 182 dnp->dn_nlevels = BSWAP_8(dnp->dn_nlevels); 183 dnp->dn_nblkptr = BSWAP_8(dnp->dn_nblkptr); 184 dnp->dn_bonustype = BSWAP_8(dnp->dn_bonustype); 185 dnp->dn_checksum = BSWAP_8(dnp->dn_checksum); 186 dnp->dn_compress = BSWAP_8(dnp->dn_compress); 187 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 188 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 189 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 190 dnp->dn_secphys = BSWAP_64(dnp->dn_secphys); 191 192 /* 193 * dn_nblkptr is only one byte, so it's OK to read it in either 194 * byte order. We can't read dn_bouslen. 195 */ 196 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 197 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 198 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 199 buf64[i] = BSWAP_64(buf64[i]); 200 201 /* 202 * OK to check dn_bonuslen for zero, because it won't matter if 203 * we have the wrong byte order. This is necessary because the 204 * dnode dnode is smaller than a regular dnode. 205 */ 206 if (dnp->dn_bonuslen != 0) { 207 /* 208 * Note that the bonus length calculated here may be 209 * longer than the actual bonus buffer. This is because 210 * we always put the bonus buffer after the last block 211 * pointer (instead of packing it against the end of the 212 * dnode buffer). 213 */ 214 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 215 size_t len = DN_MAX_BONUSLEN - off; 216 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 217 } 218 } 219 220 void 221 dnode_buf_byteswap(void *vbuf, size_t size) 222 { 223 dnode_phys_t *buf = vbuf; 224 int i; 225 226 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 227 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 228 229 size >>= DNODE_SHIFT; 230 for (i = 0; i < size; i++) { 231 dnode_byteswap(buf); 232 buf++; 233 } 234 } 235 236 static int 237 free_range_compar(const void *node1, const void *node2) 238 { 239 const free_range_t *rp1 = node1; 240 const free_range_t *rp2 = node2; 241 242 if (rp1->fr_blkid < rp2->fr_blkid) 243 return (-1); 244 else if (rp1->fr_blkid > rp2->fr_blkid) 245 return (1); 246 else return (0); 247 } 248 249 static void 250 dnode_setdblksz(dnode_t *dn, int size) 251 { 252 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 253 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 254 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 255 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 256 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 257 dn->dn_datablksz = size; 258 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 259 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 260 } 261 262 static dnode_t * 263 dnode_create(objset_impl_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 264 uint64_t object) 265 { 266 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 267 (void) dnode_cons(dn, NULL, 0); /* XXX */ 268 269 dn->dn_objset = os; 270 dn->dn_object = object; 271 dn->dn_dbuf = db; 272 dn->dn_phys = dnp; 273 274 if (dnp->dn_datablkszsec) 275 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 276 dn->dn_indblkshift = dnp->dn_indblkshift; 277 dn->dn_nlevels = dnp->dn_nlevels; 278 dn->dn_type = dnp->dn_type; 279 dn->dn_nblkptr = dnp->dn_nblkptr; 280 dn->dn_checksum = dnp->dn_checksum; 281 dn->dn_compress = dnp->dn_compress; 282 dn->dn_bonustype = dnp->dn_bonustype; 283 dn->dn_bonuslen = dnp->dn_bonuslen; 284 dn->dn_maxblkid = dnp->dn_maxblkid; 285 286 dmu_zfetch_init(&dn->dn_zfetch, dn); 287 288 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 289 mutex_enter(&os->os_lock); 290 list_insert_head(&os->os_dnodes, dn); 291 mutex_exit(&os->os_lock); 292 293 return (dn); 294 } 295 296 static void 297 dnode_destroy(dnode_t *dn) 298 { 299 objset_impl_t *os = dn->dn_objset; 300 301 mutex_enter(&os->os_lock); 302 list_remove(&os->os_dnodes, dn); 303 mutex_exit(&os->os_lock); 304 305 if (dn->dn_dirtyctx_firstset) { 306 kmem_free(dn->dn_dirtyctx_firstset, 1); 307 dn->dn_dirtyctx_firstset = NULL; 308 } 309 dmu_zfetch_rele(&dn->dn_zfetch); 310 if (dn->dn_bonus) { 311 mutex_enter(&dn->dn_bonus->db_mtx); 312 dbuf_evict(dn->dn_bonus); 313 dn->dn_bonus = NULL; 314 } 315 kmem_cache_free(dnode_cache, dn); 316 } 317 318 void 319 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 320 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 321 { 322 int i; 323 324 if (blocksize == 0) 325 blocksize = 1 << zfs_default_bs; 326 else if (blocksize > SPA_MAXBLOCKSIZE) 327 blocksize = SPA_MAXBLOCKSIZE; 328 else 329 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 330 331 if (ibs == 0) 332 ibs = zfs_default_ibs; 333 334 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 335 336 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 337 dn->dn_object, tx->tx_txg, blocksize, ibs); 338 339 ASSERT(dn->dn_type == DMU_OT_NONE); 340 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 341 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 342 ASSERT(ot != DMU_OT_NONE); 343 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 344 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 345 (bonustype != DMU_OT_NONE && bonuslen != 0)); 346 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 347 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 348 ASSERT(dn->dn_type == DMU_OT_NONE); 349 ASSERT3U(dn->dn_maxblkid, ==, 0); 350 ASSERT3U(dn->dn_allocated_txg, ==, 0); 351 ASSERT3U(dn->dn_assigned_txg, ==, 0); 352 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 353 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 354 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 355 356 for (i = 0; i < TXG_SIZE; i++) { 357 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 358 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 359 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 360 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 361 ASSERT3P(list_head(&dn->dn_dirty_dbufs[i]), ==, NULL); 362 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 363 } 364 365 dn->dn_type = ot; 366 dnode_setdblksz(dn, blocksize); 367 dn->dn_indblkshift = ibs; 368 dn->dn_nlevels = 1; 369 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 370 dn->dn_bonustype = bonustype; 371 dn->dn_bonuslen = bonuslen; 372 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 373 dn->dn_compress = ZIO_COMPRESS_INHERIT; 374 dn->dn_dirtyctx = 0; 375 376 dn->dn_free_txg = 0; 377 if (dn->dn_dirtyctx_firstset) { 378 kmem_free(dn->dn_dirtyctx_firstset, 1); 379 dn->dn_dirtyctx_firstset = NULL; 380 } 381 382 dn->dn_allocated_txg = tx->tx_txg; 383 384 dnode_setdirty(dn, tx); 385 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 386 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 387 } 388 389 void 390 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 391 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 392 { 393 int i; 394 395 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 396 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 397 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 398 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 399 ASSERT(tx->tx_txg != 0); 400 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 401 (bonustype != DMU_OT_NONE && bonuslen != 0)); 402 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 403 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 404 405 for (i = 0; i < TXG_SIZE; i++) 406 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 407 408 /* clean up any unreferenced dbufs */ 409 (void) dnode_evict_dbufs(dn, 0); 410 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 411 412 /* 413 * XXX I should really have a generation number to tell if we 414 * need to do this... 415 */ 416 if (blocksize != dn->dn_datablksz || 417 dn->dn_bonustype != bonustype || dn->dn_bonuslen != bonuslen) { 418 /* free all old data */ 419 dnode_free_range(dn, 0, -1ULL, tx); 420 } 421 422 /* change blocksize */ 423 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 424 dnode_setdblksz(dn, blocksize); 425 dnode_setdirty(dn, tx); 426 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 427 rw_exit(&dn->dn_struct_rwlock); 428 429 /* change type */ 430 dn->dn_type = ot; 431 432 if (dn->dn_bonuslen != bonuslen) { 433 dmu_buf_impl_t *db = NULL; 434 435 /* change bonus size */ 436 if (bonuslen == 0) 437 bonuslen = 1; /* XXX */ 438 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 439 if (dn->dn_bonus == NULL) 440 dn->dn_bonus = dbuf_create_bonus(dn); 441 db = dn->dn_bonus; 442 rw_exit(&dn->dn_struct_rwlock); 443 if (refcount_add(&db->db_holds, FTAG) == 1) 444 dnode_add_ref(dn, db); 445 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED)); 446 mutex_enter(&db->db_mtx); 447 ASSERT3U(db->db.db_size, ==, dn->dn_bonuslen); 448 ASSERT(db->db.db_data != NULL); 449 db->db.db_size = bonuslen; 450 mutex_exit(&db->db_mtx); 451 dbuf_dirty(db, tx); 452 dbuf_rele(db, FTAG); 453 } 454 455 /* change bonus size and type */ 456 mutex_enter(&dn->dn_mtx); 457 dn->dn_bonustype = bonustype; 458 dn->dn_bonuslen = bonuslen; 459 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 460 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 461 dn->dn_compress = ZIO_COMPRESS_INHERIT; 462 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 463 464 dn->dn_allocated_txg = tx->tx_txg; 465 mutex_exit(&dn->dn_mtx); 466 } 467 468 void 469 dnode_special_close(dnode_t *dn) 470 { 471 /* 472 * Wait for final references to the dnode to clear. This can 473 * only happen if the arc is asyncronously evicting state that 474 * has a hold on this dnode while we are trying to evict this 475 * dnode. 476 */ 477 while (refcount_count(&dn->dn_holds) > 0) 478 delay(1); 479 dnode_destroy(dn); 480 } 481 482 dnode_t * 483 dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 484 { 485 dnode_t *dn = dnode_create(os, dnp, NULL, object); 486 DNODE_VERIFY(dn); 487 return (dn); 488 } 489 490 static void 491 dnode_buf_pageout(dmu_buf_t *db, void *arg) 492 { 493 dnode_t **children_dnodes = arg; 494 int i; 495 int epb = db->db_size >> DNODE_SHIFT; 496 497 for (i = 0; i < epb; i++) { 498 dnode_t *dn = children_dnodes[i]; 499 int n; 500 501 if (dn == NULL) 502 continue; 503 #ifdef ZFS_DEBUG 504 /* 505 * If there are holds on this dnode, then there should 506 * be holds on the dnode's containing dbuf as well; thus 507 * it wouldn't be eligable for eviction and this function 508 * would not have been called. 509 */ 510 ASSERT(refcount_is_zero(&dn->dn_holds)); 511 ASSERT(list_head(&dn->dn_dbufs) == NULL); 512 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 513 514 for (n = 0; n < TXG_SIZE; n++) 515 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 516 #endif 517 children_dnodes[i] = NULL; 518 dnode_destroy(dn); 519 } 520 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 521 } 522 523 /* 524 * errors: 525 * EINVAL - invalid object number. 526 * EIO - i/o error. 527 * succeeds even for free dnodes. 528 */ 529 int 530 dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 531 void *tag, dnode_t **dnp) 532 { 533 int epb, idx, err; 534 int drop_struct_lock = FALSE; 535 int type; 536 uint64_t blk; 537 dnode_t *mdn, *dn; 538 dmu_buf_impl_t *db; 539 dnode_t **children_dnodes; 540 541 if (object == 0 || object >= DN_MAX_OBJECT) 542 return (EINVAL); 543 544 mdn = os->os_meta_dnode; 545 546 DNODE_VERIFY(mdn); 547 548 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 549 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 550 drop_struct_lock = TRUE; 551 } 552 553 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 554 555 db = dbuf_hold(mdn, blk, FTAG); 556 if (drop_struct_lock) 557 rw_exit(&mdn->dn_struct_rwlock); 558 if (db == NULL) 559 return (EIO); 560 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 561 if (err) { 562 dbuf_rele(db, FTAG); 563 return (err); 564 } 565 566 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 567 epb = db->db.db_size >> DNODE_SHIFT; 568 569 idx = object & (epb-1); 570 571 children_dnodes = dmu_buf_get_user(&db->db); 572 if (children_dnodes == NULL) { 573 dnode_t **winner; 574 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 575 KM_SLEEP); 576 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 577 dnode_buf_pageout)) { 578 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 579 children_dnodes = winner; 580 } 581 } 582 583 if ((dn = children_dnodes[idx]) == NULL) { 584 dnode_t *winner; 585 dn = dnode_create(os, (dnode_phys_t *)db->db.db_data+idx, 586 db, object); 587 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 588 if (winner != NULL) { 589 dnode_destroy(dn); 590 dn = winner; 591 } 592 } 593 594 mutex_enter(&dn->dn_mtx); 595 type = dn->dn_type; 596 if (dn->dn_free_txg || 597 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 598 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 599 mutex_exit(&dn->dn_mtx); 600 dbuf_rele(db, FTAG); 601 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 602 } 603 mutex_exit(&dn->dn_mtx); 604 605 if (refcount_add(&dn->dn_holds, tag) == 1) 606 dbuf_add_ref(db, dn); 607 608 DNODE_VERIFY(dn); 609 ASSERT3P(dn->dn_dbuf, ==, db); 610 ASSERT3U(dn->dn_object, ==, object); 611 dbuf_rele(db, FTAG); 612 613 *dnp = dn; 614 return (0); 615 } 616 617 /* 618 * Return held dnode if the object is allocated, NULL if not. 619 */ 620 int 621 dnode_hold(objset_impl_t *os, uint64_t object, void *tag, dnode_t **dnp) 622 { 623 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 624 } 625 626 void 627 dnode_add_ref(dnode_t *dn, void *tag) 628 { 629 ASSERT(refcount_count(&dn->dn_holds) > 0); 630 (void) refcount_add(&dn->dn_holds, tag); 631 } 632 633 void 634 dnode_rele(dnode_t *dn, void *tag) 635 { 636 uint64_t refs; 637 638 refs = refcount_remove(&dn->dn_holds, tag); 639 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 640 if (refs == 0 && dn->dn_dbuf) 641 dbuf_rele(dn->dn_dbuf, dn); 642 } 643 644 void 645 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 646 { 647 objset_impl_t *os = dn->dn_objset; 648 uint64_t txg = tx->tx_txg; 649 650 if (dn->dn_object == DMU_META_DNODE_OBJECT) 651 return; 652 653 DNODE_VERIFY(dn); 654 655 #ifdef ZFS_DEBUG 656 mutex_enter(&dn->dn_mtx); 657 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 658 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 659 mutex_exit(&dn->dn_mtx); 660 #endif 661 662 mutex_enter(&os->os_lock); 663 664 /* 665 * If we are already marked dirty, we're done. 666 */ 667 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 668 mutex_exit(&os->os_lock); 669 return; 670 } 671 672 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 673 ASSERT(dn->dn_datablksz != 0); 674 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 675 676 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 677 dn->dn_object, txg); 678 679 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 680 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 681 } else { 682 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 683 } 684 685 mutex_exit(&os->os_lock); 686 687 /* 688 * The dnode maintains a hold on its containing dbuf as 689 * long as there are holds on it. Each instantiated child 690 * dbuf maintaines a hold on the dnode. When the last child 691 * drops its hold, the dnode will drop its hold on the 692 * containing dbuf. We add a "dirty hold" here so that the 693 * dnode will hang around after we finish processing its 694 * children. 695 */ 696 dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg); 697 698 dbuf_dirty(dn->dn_dbuf, tx); 699 700 dsl_dataset_dirty(os->os_dsl_dataset, tx); 701 } 702 703 void 704 dnode_free(dnode_t *dn, dmu_tx_t *tx) 705 { 706 int txgoff = tx->tx_txg & TXG_MASK; 707 708 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 709 710 /* we should be the only holder... hopefully */ 711 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 712 713 mutex_enter(&dn->dn_mtx); 714 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 715 mutex_exit(&dn->dn_mtx); 716 return; 717 } 718 dn->dn_free_txg = tx->tx_txg; 719 mutex_exit(&dn->dn_mtx); 720 721 /* 722 * If the dnode is already dirty, it needs to be moved from 723 * the dirty list to the free list. 724 */ 725 mutex_enter(&dn->dn_objset->os_lock); 726 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 727 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 728 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 729 mutex_exit(&dn->dn_objset->os_lock); 730 } else { 731 mutex_exit(&dn->dn_objset->os_lock); 732 dnode_setdirty(dn, tx); 733 } 734 } 735 736 /* 737 * Try to change the block size for the indicated dnode. This can only 738 * succeed if there are no blocks allocated or dirty beyond first block 739 */ 740 int 741 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 742 { 743 dmu_buf_impl_t *db, *db_next; 744 int have_db0 = FALSE; 745 int err = ENOTSUP; 746 747 if (size == 0) 748 size = SPA_MINBLOCKSIZE; 749 if (size > SPA_MAXBLOCKSIZE) 750 size = SPA_MAXBLOCKSIZE; 751 else 752 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 753 754 if (ibs == 0) 755 ibs = dn->dn_indblkshift; 756 757 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && 758 ibs == dn->dn_indblkshift) 759 return (0); 760 761 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 762 763 /* Check for any allocated blocks beyond the first */ 764 if (dn->dn_phys->dn_maxblkid != 0) 765 goto end; 766 767 mutex_enter(&dn->dn_dbufs_mtx); 768 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 769 db_next = list_next(&dn->dn_dbufs, db); 770 771 if (db->db_blkid == 0) { 772 have_db0 = TRUE; 773 } else if (db->db_blkid != DB_BONUS_BLKID) { 774 mutex_exit(&dn->dn_dbufs_mtx); 775 goto end; 776 } 777 } 778 mutex_exit(&dn->dn_dbufs_mtx); 779 780 db = NULL; 781 if (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || have_db0) { 782 /* obtain the old block */ 783 db = dbuf_hold(dn, 0, FTAG); 784 dbuf_new_size(db, size, tx); 785 } 786 787 dnode_setdblksz(dn, size); 788 dn->dn_indblkshift = ibs; 789 dnode_setdirty(dn, tx); 790 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 791 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 792 793 if (db) 794 dbuf_rele(db, FTAG); 795 796 err = 0; 797 end: 798 rw_exit(&dn->dn_struct_rwlock); 799 return (err); 800 } 801 802 uint64_t 803 dnode_max_nonzero_offset(dnode_t *dn) 804 { 805 if (dn->dn_phys->dn_maxblkid == 0 && 806 BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0])) 807 return (0); 808 else 809 return ((dn->dn_phys->dn_maxblkid+1) * dn->dn_datablksz); 810 } 811 812 void 813 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx) 814 { 815 uint64_t txgoff = tx->tx_txg & TXG_MASK; 816 int drop_struct_lock = FALSE; 817 int epbs, new_nlevels; 818 uint64_t sz; 819 820 ASSERT(blkid != DB_BONUS_BLKID); 821 822 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 823 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 824 drop_struct_lock = TRUE; 825 } 826 827 if (blkid <= dn->dn_maxblkid) 828 goto out; 829 830 dn->dn_maxblkid = blkid; 831 832 /* 833 * Compute the number of levels necessary to support the new maxblkid. 834 */ 835 new_nlevels = 1; 836 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 837 for (sz = dn->dn_nblkptr; 838 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 839 new_nlevels++; 840 841 if (new_nlevels > dn->dn_nlevels) { 842 int old_nlevels = dn->dn_nlevels; 843 dmu_buf_impl_t *db; 844 845 dn->dn_nlevels = new_nlevels; 846 847 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 848 dn->dn_next_nlevels[txgoff] = new_nlevels; 849 850 /* Dirty the left indirects. */ 851 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 852 dbuf_dirty(db, tx); 853 dbuf_rele(db, FTAG); 854 855 } 856 857 out: 858 if (drop_struct_lock) 859 rw_exit(&dn->dn_struct_rwlock); 860 } 861 862 void 863 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 864 { 865 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 866 avl_index_t where; 867 free_range_t *rp; 868 free_range_t rp_tofind; 869 uint64_t endblk = blkid + nblks; 870 871 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 872 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 873 874 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 875 blkid, nblks, tx->tx_txg); 876 rp_tofind.fr_blkid = blkid; 877 rp = avl_find(tree, &rp_tofind, &where); 878 if (rp == NULL) 879 rp = avl_nearest(tree, where, AVL_BEFORE); 880 if (rp == NULL) 881 rp = avl_nearest(tree, where, AVL_AFTER); 882 883 while (rp && (rp->fr_blkid <= blkid + nblks)) { 884 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 885 free_range_t *nrp = AVL_NEXT(tree, rp); 886 887 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 888 /* clear this entire range */ 889 avl_remove(tree, rp); 890 kmem_free(rp, sizeof (free_range_t)); 891 } else if (blkid <= rp->fr_blkid && 892 endblk > rp->fr_blkid && endblk < fr_endblk) { 893 /* clear the beginning of this range */ 894 rp->fr_blkid = endblk; 895 rp->fr_nblks = fr_endblk - endblk; 896 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 897 endblk >= fr_endblk) { 898 /* clear the end of this range */ 899 rp->fr_nblks = blkid - rp->fr_blkid; 900 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 901 /* clear a chunk out of this range */ 902 free_range_t *new_rp = 903 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 904 905 new_rp->fr_blkid = endblk; 906 new_rp->fr_nblks = fr_endblk - endblk; 907 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 908 rp->fr_nblks = blkid - rp->fr_blkid; 909 } 910 /* there may be no overlap */ 911 rp = nrp; 912 } 913 } 914 915 void 916 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 917 { 918 dmu_buf_impl_t *db; 919 uint64_t start, objsize, blkid, nblks; 920 int blkshift, blksz, tail, head, epbs; 921 int trunc = FALSE; 922 923 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 924 blksz = dn->dn_datablksz; 925 blkshift = dn->dn_datablkshift; 926 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 927 928 /* If the range is past the end of the file, this is a no-op */ 929 objsize = blksz * (dn->dn_maxblkid+1); 930 if (off >= objsize) 931 goto out; 932 if (len == -1ULL) { 933 len = UINT64_MAX - off; 934 trunc = TRUE; 935 } 936 937 /* 938 * First, block align the region to free: 939 */ 940 if (dn->dn_maxblkid == 0) { 941 if (off == 0) { 942 head = 0; 943 } else { 944 head = blksz - off; 945 ASSERT3U(head, >, 0); 946 } 947 start = off; 948 } else { 949 ASSERT(ISP2(blksz)); 950 head = P2NPHASE(off, blksz); 951 start = P2PHASE(off, blksz); 952 } 953 /* zero out any partial block data at the start of the range */ 954 if (head) { 955 ASSERT3U(start + head, ==, blksz); 956 if (len < head) 957 head = len; 958 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 959 FTAG, &db) == 0) { 960 caddr_t data; 961 962 /* don't dirty if it isn't on disk and isn't dirty */ 963 if (db->db_dirtied || 964 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 965 rw_exit(&dn->dn_struct_rwlock); 966 dbuf_will_dirty(db, tx); 967 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 968 data = db->db.db_data; 969 bzero(data + start, head); 970 } 971 dbuf_rele(db, FTAG); 972 } 973 off += head; 974 len -= head; 975 } 976 /* If the range was less than one block, we are done */ 977 if (len == 0) 978 goto out; 979 980 /* If the remaining range is past the end of the file, we are done */ 981 if (off > dn->dn_maxblkid << blkshift) 982 goto out; 983 984 if (off + len == UINT64_MAX) 985 tail = 0; 986 else 987 tail = P2PHASE(len, blksz); 988 989 ASSERT3U(P2PHASE(off, blksz), ==, 0); 990 /* zero out any partial block data at the end of the range */ 991 if (tail) { 992 if (len < tail) 993 tail = len; 994 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 995 TRUE, FTAG, &db) == 0) { 996 /* don't dirty if it isn't on disk and isn't dirty */ 997 if (db->db_dirtied || 998 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 999 rw_exit(&dn->dn_struct_rwlock); 1000 dbuf_will_dirty(db, tx); 1001 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1002 bzero(db->db.db_data, tail); 1003 } 1004 dbuf_rele(db, FTAG); 1005 } 1006 len -= tail; 1007 } 1008 /* If the range did not include a full block, we are done */ 1009 if (len == 0) 1010 goto out; 1011 1012 /* dirty the left indirects */ 1013 if (dn->dn_nlevels > 1 && off != 0) { 1014 db = dbuf_hold_level(dn, 1, 1015 (off - head) >> (blkshift + epbs), FTAG); 1016 dbuf_will_dirty(db, tx); 1017 dbuf_rele(db, FTAG); 1018 } 1019 1020 /* dirty the right indirects */ 1021 if (dn->dn_nlevels > 1 && !trunc) { 1022 db = dbuf_hold_level(dn, 1, 1023 (off + len + tail - 1) >> (blkshift + epbs), FTAG); 1024 dbuf_will_dirty(db, tx); 1025 dbuf_rele(db, FTAG); 1026 } 1027 1028 /* 1029 * Finally, add this range to the dnode range list, we 1030 * will finish up this free operation in the syncing phase. 1031 */ 1032 ASSERT(IS_P2ALIGNED(off, 1<<blkshift)); 1033 ASSERT(off + len == UINT64_MAX || IS_P2ALIGNED(len, 1<<blkshift)); 1034 blkid = off >> blkshift; 1035 nblks = len >> blkshift; 1036 1037 if (trunc) 1038 dn->dn_maxblkid = (blkid ? blkid - 1 : 0); 1039 1040 mutex_enter(&dn->dn_mtx); 1041 dnode_clear_range(dn, blkid, nblks, tx); 1042 { 1043 free_range_t *rp, *found; 1044 avl_index_t where; 1045 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1046 1047 /* Add new range to dn_ranges */ 1048 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1049 rp->fr_blkid = blkid; 1050 rp->fr_nblks = nblks; 1051 found = avl_find(tree, rp, &where); 1052 ASSERT(found == NULL); 1053 avl_insert(tree, rp, where); 1054 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1055 blkid, nblks, tx->tx_txg); 1056 } 1057 mutex_exit(&dn->dn_mtx); 1058 1059 dbuf_free_range(dn, blkid, nblks, tx); 1060 dnode_setdirty(dn, tx); 1061 out: 1062 rw_exit(&dn->dn_struct_rwlock); 1063 } 1064 1065 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1066 uint64_t 1067 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1068 { 1069 free_range_t range_tofind; 1070 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1071 int i; 1072 1073 if (blkid == DB_BONUS_BLKID) 1074 return (FALSE); 1075 1076 /* 1077 * If we're in the process of opening the pool, dp will not be 1078 * set yet, but there shouldn't be anything dirty. 1079 */ 1080 if (dp == NULL) 1081 return (FALSE); 1082 1083 if (dn->dn_free_txg) 1084 return (TRUE); 1085 1086 /* 1087 * If dn_datablkshift is not set, then there's only a single 1088 * block, in which case there will never be a free range so it 1089 * won't matter. 1090 */ 1091 range_tofind.fr_blkid = blkid; 1092 mutex_enter(&dn->dn_mtx); 1093 for (i = 0; i < TXG_SIZE; i++) { 1094 free_range_t *range_found; 1095 avl_index_t idx; 1096 1097 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1098 if (range_found) { 1099 ASSERT(range_found->fr_nblks > 0); 1100 break; 1101 } 1102 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1103 if (range_found && 1104 range_found->fr_blkid + range_found->fr_nblks > blkid) 1105 break; 1106 } 1107 mutex_exit(&dn->dn_mtx); 1108 return (i < TXG_SIZE); 1109 } 1110 1111 /* call from syncing context when we actually write/free space for this dnode */ 1112 void 1113 dnode_diduse_space(dnode_t *dn, int64_t space) 1114 { 1115 uint64_t sectors; 1116 1117 dprintf_dnode(dn, "dn=%p dnp=%p secphys=%llu space=%lld\n", 1118 dn, dn->dn_phys, 1119 (u_longlong_t)dn->dn_phys->dn_secphys, 1120 (longlong_t)space); 1121 1122 ASSERT(P2PHASE(space, 1<<DEV_BSHIFT) == 0); 1123 1124 mutex_enter(&dn->dn_mtx); 1125 if (space > 0) { 1126 sectors = space >> DEV_BSHIFT; 1127 ASSERT3U(dn->dn_phys->dn_secphys + sectors, >=, 1128 dn->dn_phys->dn_secphys); 1129 dn->dn_phys->dn_secphys += sectors; 1130 } else { 1131 sectors = -space >> DEV_BSHIFT; 1132 ASSERT3U(dn->dn_phys->dn_secphys, >=, sectors); 1133 dn->dn_phys->dn_secphys -= sectors; 1134 } 1135 mutex_exit(&dn->dn_mtx); 1136 } 1137 1138 /* 1139 * Call when we think we're going to write/free space in open context. 1140 * Be conservative (ie. OK to write less than this or free more than 1141 * this, but don't write more or free less). 1142 */ 1143 void 1144 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1145 { 1146 objset_impl_t *os = dn->dn_objset; 1147 dsl_dataset_t *ds = os->os_dsl_dataset; 1148 1149 if (space > 0) 1150 space = spa_get_asize(os->os_spa, space); 1151 1152 if (ds) 1153 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1154 1155 dmu_tx_willuse_space(tx, space); 1156 } 1157 1158 static int 1159 dnode_next_offset_level(dnode_t *dn, boolean_t hole, uint64_t *offset, 1160 int lvl, uint64_t blkfill) 1161 { 1162 dmu_buf_impl_t *db = NULL; 1163 void *data = NULL; 1164 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1165 uint64_t epb = 1ULL << epbs; 1166 uint64_t minfill, maxfill; 1167 int i, error, span; 1168 1169 dprintf("probing object %llu offset %llx level %d of %u\n", 1170 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1171 1172 if (lvl == dn->dn_phys->dn_nlevels) { 1173 error = 0; 1174 epb = dn->dn_phys->dn_nblkptr; 1175 data = dn->dn_phys->dn_blkptr; 1176 } else { 1177 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1178 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1179 if (error) { 1180 if (error == ENOENT) 1181 return (hole ? 0 : ESRCH); 1182 return (error); 1183 } 1184 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1185 if (error) { 1186 dbuf_rele(db, FTAG); 1187 return (error); 1188 } 1189 data = db->db.db_data; 1190 } 1191 1192 if (lvl == 0) { 1193 dnode_phys_t *dnp = data; 1194 span = DNODE_SHIFT; 1195 ASSERT(dn->dn_type == DMU_OT_DNODE); 1196 1197 for (i = (*offset >> span) & (blkfill - 1); i < blkfill; i++) { 1198 if (!dnp[i].dn_type == hole) 1199 break; 1200 *offset += 1ULL << span; 1201 } 1202 if (i == blkfill) 1203 error = ESRCH; 1204 } else { 1205 blkptr_t *bp = data; 1206 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1207 minfill = 0; 1208 maxfill = blkfill << ((lvl - 1) * epbs); 1209 1210 if (hole) 1211 maxfill--; 1212 else 1213 minfill++; 1214 1215 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1216 i < epb; i++) { 1217 if (bp[i].blk_fill >= minfill && 1218 bp[i].blk_fill <= maxfill) 1219 break; 1220 *offset += 1ULL << span; 1221 } 1222 if (i >= epb) 1223 error = ESRCH; 1224 } 1225 1226 if (db) 1227 dbuf_rele(db, FTAG); 1228 1229 return (error); 1230 } 1231 1232 /* 1233 * Find the next hole, data, or sparse region at or after *offset. 1234 * The value 'blkfill' tells us how many items we expect to find 1235 * in an L0 data block; this value is 1 for normal objects, 1236 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1237 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1238 * Examples: 1239 * 1240 * dnode_next_offset(dn, hole, offset, 1, 1); 1241 * Finds the next hole/data in a file. 1242 * Used in dmu_offset_next(). 1243 * 1244 * dnode_next_offset(mdn, hole, offset, 0, DNODES_PER_BLOCK); 1245 * Finds the next free/allocated dnode an objset's meta-dnode. 1246 * Used in dmu_object_next(). 1247 * 1248 * dnode_next_offset(mdn, TRUE, offset, 2, DNODES_PER_BLOCK >> 2); 1249 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1250 * Used in dmu_object_alloc(). 1251 */ 1252 int 1253 dnode_next_offset(dnode_t *dn, boolean_t hole, uint64_t *offset, 1254 int minlvl, uint64_t blkfill) 1255 { 1256 int lvl, maxlvl; 1257 int error = 0; 1258 uint64_t initial_offset = *offset; 1259 1260 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1261 1262 if (dn->dn_phys->dn_nlevels == 0) { 1263 rw_exit(&dn->dn_struct_rwlock); 1264 return (ESRCH); 1265 } 1266 1267 if (dn->dn_datablkshift == 0) { 1268 if (*offset < dn->dn_datablksz) { 1269 if (hole) 1270 *offset = dn->dn_datablksz; 1271 } else { 1272 error = ESRCH; 1273 } 1274 rw_exit(&dn->dn_struct_rwlock); 1275 return (error); 1276 } 1277 1278 maxlvl = dn->dn_phys->dn_nlevels; 1279 1280 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1281 error = dnode_next_offset_level(dn, hole, offset, lvl, blkfill); 1282 if (error != ESRCH) 1283 break; 1284 } 1285 1286 while (--lvl >= minlvl && error == 0) 1287 error = dnode_next_offset_level(dn, hole, offset, lvl, blkfill); 1288 1289 rw_exit(&dn->dn_struct_rwlock); 1290 1291 if (error == 0 && initial_offset > *offset) 1292 error = ESRCH; 1293 1294 return (error); 1295 } 1296