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 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/dbuf.h> 28 #include <sys/dnode.h> 29 #include <sys/dmu.h> 30 #include <sys/dmu_impl.h> 31 #include <sys/dmu_tx.h> 32 #include <sys/dmu_objset.h> 33 #include <sys/dsl_dir.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/spa.h> 36 #include <sys/zio.h> 37 #include <sys/dmu_zfetch.h> 38 39 static int free_range_compar(const void *node1, const void *node2); 40 41 static kmem_cache_t *dnode_cache; 42 43 static dnode_phys_t dnode_phys_zero; 44 45 int zfs_default_bs = SPA_MINBLOCKSHIFT; 46 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 47 48 /* ARGSUSED */ 49 static int 50 dnode_cons(void *arg, void *unused, int kmflag) 51 { 52 int i; 53 dnode_t *dn = arg; 54 bzero(dn, sizeof (dnode_t)); 55 56 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 57 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 58 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 59 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 60 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 cv_destroy(&dn->dn_notxholds); 90 refcount_destroy(&dn->dn_holds); 91 refcount_destroy(&dn->dn_tx_holds); 92 93 for (i = 0; i < TXG_SIZE; i++) { 94 avl_destroy(&dn->dn_ranges[i]); 95 list_destroy(&dn->dn_dirty_records[i]); 96 } 97 98 list_destroy(&dn->dn_dbufs); 99 } 100 101 void 102 dnode_init(void) 103 { 104 dnode_cache = kmem_cache_create("dnode_t", 105 sizeof (dnode_t), 106 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 107 } 108 109 void 110 dnode_fini(void) 111 { 112 kmem_cache_destroy(dnode_cache); 113 } 114 115 116 #ifdef ZFS_DEBUG 117 void 118 dnode_verify(dnode_t *dn) 119 { 120 int drop_struct_lock = FALSE; 121 122 ASSERT(dn->dn_phys); 123 ASSERT(dn->dn_objset); 124 125 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 126 127 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 128 return; 129 130 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 131 rw_enter(&dn->dn_struct_rwlock, RW_READER); 132 drop_struct_lock = TRUE; 133 } 134 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 135 int i; 136 ASSERT3U(dn->dn_indblkshift, >=, 0); 137 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 138 if (dn->dn_datablkshift) { 139 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 140 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 141 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 142 } 143 ASSERT3U(dn->dn_nlevels, <=, 30); 144 ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); 145 ASSERT3U(dn->dn_nblkptr, >=, 1); 146 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 147 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 148 ASSERT3U(dn->dn_datablksz, ==, 149 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 150 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 151 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 152 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 153 for (i = 0; i < TXG_SIZE; i++) { 154 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 155 } 156 } 157 if (dn->dn_phys->dn_type != DMU_OT_NONE) 158 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 159 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 160 if (dn->dn_dbuf != NULL) { 161 ASSERT3P(dn->dn_phys, ==, 162 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 163 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 164 } 165 if (drop_struct_lock) 166 rw_exit(&dn->dn_struct_rwlock); 167 } 168 #endif 169 170 void 171 dnode_byteswap(dnode_phys_t *dnp) 172 { 173 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 174 int i; 175 176 if (dnp->dn_type == DMU_OT_NONE) { 177 bzero(dnp, sizeof (dnode_phys_t)); 178 return; 179 } 180 181 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 182 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 183 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 184 dnp->dn_used = BSWAP_64(dnp->dn_used); 185 186 /* 187 * dn_nblkptr is only one byte, so it's OK to read it in either 188 * byte order. We can't read dn_bouslen. 189 */ 190 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 191 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 192 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 193 buf64[i] = BSWAP_64(buf64[i]); 194 195 /* 196 * OK to check dn_bonuslen for zero, because it won't matter if 197 * we have the wrong byte order. This is necessary because the 198 * dnode dnode is smaller than a regular dnode. 199 */ 200 if (dnp->dn_bonuslen != 0) { 201 /* 202 * Note that the bonus length calculated here may be 203 * longer than the actual bonus buffer. This is because 204 * we always put the bonus buffer after the last block 205 * pointer (instead of packing it against the end of the 206 * dnode buffer). 207 */ 208 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 209 size_t len = DN_MAX_BONUSLEN - off; 210 ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); 211 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 212 } 213 } 214 215 void 216 dnode_buf_byteswap(void *vbuf, size_t size) 217 { 218 dnode_phys_t *buf = vbuf; 219 int i; 220 221 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 222 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 223 224 size >>= DNODE_SHIFT; 225 for (i = 0; i < size; i++) { 226 dnode_byteswap(buf); 227 buf++; 228 } 229 } 230 231 static int 232 free_range_compar(const void *node1, const void *node2) 233 { 234 const free_range_t *rp1 = node1; 235 const free_range_t *rp2 = node2; 236 237 if (rp1->fr_blkid < rp2->fr_blkid) 238 return (-1); 239 else if (rp1->fr_blkid > rp2->fr_blkid) 240 return (1); 241 else return (0); 242 } 243 244 void 245 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 246 { 247 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 248 249 dnode_setdirty(dn, tx); 250 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 251 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 252 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 253 dn->dn_bonuslen = newsize; 254 if (newsize == 0) 255 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 256 else 257 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 258 rw_exit(&dn->dn_struct_rwlock); 259 } 260 261 static void 262 dnode_setdblksz(dnode_t *dn, int size) 263 { 264 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 265 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 266 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 267 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 268 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 269 dn->dn_datablksz = size; 270 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 271 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 272 } 273 274 static dnode_t * 275 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 276 uint64_t object) 277 { 278 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 279 (void) dnode_cons(dn, NULL, 0); /* XXX */ 280 281 dn->dn_objset = os; 282 dn->dn_object = object; 283 dn->dn_dbuf = db; 284 dn->dn_phys = dnp; 285 286 if (dnp->dn_datablkszsec) 287 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 288 dn->dn_indblkshift = dnp->dn_indblkshift; 289 dn->dn_nlevels = dnp->dn_nlevels; 290 dn->dn_type = dnp->dn_type; 291 dn->dn_nblkptr = dnp->dn_nblkptr; 292 dn->dn_checksum = dnp->dn_checksum; 293 dn->dn_compress = dnp->dn_compress; 294 dn->dn_bonustype = dnp->dn_bonustype; 295 dn->dn_bonuslen = dnp->dn_bonuslen; 296 dn->dn_maxblkid = dnp->dn_maxblkid; 297 298 dmu_zfetch_init(&dn->dn_zfetch, dn); 299 300 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 301 mutex_enter(&os->os_lock); 302 list_insert_head(&os->os_dnodes, dn); 303 mutex_exit(&os->os_lock); 304 305 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 306 return (dn); 307 } 308 309 static void 310 dnode_destroy(dnode_t *dn) 311 { 312 objset_t *os = dn->dn_objset; 313 314 #ifdef ZFS_DEBUG 315 int i; 316 317 for (i = 0; i < TXG_SIZE; i++) { 318 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 319 ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); 320 ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); 321 } 322 ASSERT(NULL == list_head(&dn->dn_dbufs)); 323 #endif 324 ASSERT(dn->dn_oldphys == NULL); 325 326 mutex_enter(&os->os_lock); 327 list_remove(&os->os_dnodes, dn); 328 mutex_exit(&os->os_lock); 329 330 if (dn->dn_dirtyctx_firstset) { 331 kmem_free(dn->dn_dirtyctx_firstset, 1); 332 dn->dn_dirtyctx_firstset = NULL; 333 } 334 dmu_zfetch_rele(&dn->dn_zfetch); 335 if (dn->dn_bonus) { 336 mutex_enter(&dn->dn_bonus->db_mtx); 337 dbuf_evict(dn->dn_bonus); 338 dn->dn_bonus = NULL; 339 } 340 kmem_cache_free(dnode_cache, dn); 341 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 342 } 343 344 void 345 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 346 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 347 { 348 int i; 349 350 if (blocksize == 0) 351 blocksize = 1 << zfs_default_bs; 352 else if (blocksize > SPA_MAXBLOCKSIZE) 353 blocksize = SPA_MAXBLOCKSIZE; 354 else 355 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 356 357 if (ibs == 0) 358 ibs = zfs_default_ibs; 359 360 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 361 362 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 363 dn->dn_object, tx->tx_txg, blocksize, ibs); 364 365 ASSERT(dn->dn_type == DMU_OT_NONE); 366 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 367 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 368 ASSERT(ot != DMU_OT_NONE); 369 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 370 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 371 (bonustype != DMU_OT_NONE && bonuslen != 0)); 372 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 373 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 374 ASSERT(dn->dn_type == DMU_OT_NONE); 375 ASSERT3U(dn->dn_maxblkid, ==, 0); 376 ASSERT3U(dn->dn_allocated_txg, ==, 0); 377 ASSERT3U(dn->dn_assigned_txg, ==, 0); 378 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 379 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 380 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 381 382 for (i = 0; i < TXG_SIZE; i++) { 383 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 384 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 385 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 386 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 387 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 388 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 389 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 390 } 391 392 dn->dn_type = ot; 393 dnode_setdblksz(dn, blocksize); 394 dn->dn_indblkshift = ibs; 395 dn->dn_nlevels = 1; 396 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 397 dn->dn_bonustype = bonustype; 398 dn->dn_bonuslen = bonuslen; 399 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 400 dn->dn_compress = ZIO_COMPRESS_INHERIT; 401 dn->dn_dirtyctx = 0; 402 403 dn->dn_free_txg = 0; 404 if (dn->dn_dirtyctx_firstset) { 405 kmem_free(dn->dn_dirtyctx_firstset, 1); 406 dn->dn_dirtyctx_firstset = NULL; 407 } 408 409 dn->dn_allocated_txg = tx->tx_txg; 410 411 dnode_setdirty(dn, tx); 412 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 413 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 414 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 415 } 416 417 void 418 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 419 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 420 { 421 int nblkptr; 422 423 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 424 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 425 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 426 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 427 ASSERT(tx->tx_txg != 0); 428 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 429 (bonustype != DMU_OT_NONE && bonuslen != 0)); 430 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 431 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 432 433 /* clean up any unreferenced dbufs */ 434 dnode_evict_dbufs(dn); 435 436 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 437 dnode_setdirty(dn, tx); 438 if (dn->dn_datablksz != blocksize) { 439 /* change blocksize */ 440 ASSERT(dn->dn_maxblkid == 0 && 441 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 442 dnode_block_freed(dn, 0))); 443 dnode_setdblksz(dn, blocksize); 444 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 445 } 446 if (dn->dn_bonuslen != bonuslen) 447 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 448 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 449 if (dn->dn_nblkptr != nblkptr) 450 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 451 rw_exit(&dn->dn_struct_rwlock); 452 453 /* change type */ 454 dn->dn_type = ot; 455 456 /* change bonus size and type */ 457 mutex_enter(&dn->dn_mtx); 458 dn->dn_bonustype = bonustype; 459 dn->dn_bonuslen = bonuslen; 460 dn->dn_nblkptr = nblkptr; 461 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 462 dn->dn_compress = ZIO_COMPRESS_INHERIT; 463 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 464 465 /* fix up the bonus db_size */ 466 if (dn->dn_bonus) { 467 dn->dn_bonus->db.db_size = 468 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 469 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 470 } 471 472 dn->dn_allocated_txg = tx->tx_txg; 473 mutex_exit(&dn->dn_mtx); 474 } 475 476 void 477 dnode_special_close(dnode_t *dn) 478 { 479 /* 480 * Wait for final references to the dnode to clear. This can 481 * only happen if the arc is asyncronously evicting state that 482 * has a hold on this dnode while we are trying to evict this 483 * dnode. 484 */ 485 while (refcount_count(&dn->dn_holds) > 0) 486 delay(1); 487 dnode_destroy(dn); 488 } 489 490 dnode_t * 491 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object) 492 { 493 dnode_t *dn = dnode_create(os, dnp, NULL, object); 494 DNODE_VERIFY(dn); 495 return (dn); 496 } 497 498 static void 499 dnode_buf_pageout(dmu_buf_t *db, void *arg) 500 { 501 dnode_t **children_dnodes = arg; 502 int i; 503 int epb = db->db_size >> DNODE_SHIFT; 504 505 for (i = 0; i < epb; i++) { 506 dnode_t *dn = children_dnodes[i]; 507 int n; 508 509 if (dn == NULL) 510 continue; 511 #ifdef ZFS_DEBUG 512 /* 513 * If there are holds on this dnode, then there should 514 * be holds on the dnode's containing dbuf as well; thus 515 * it wouldn't be eligable for eviction and this function 516 * would not have been called. 517 */ 518 ASSERT(refcount_is_zero(&dn->dn_holds)); 519 ASSERT(list_head(&dn->dn_dbufs) == NULL); 520 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 521 522 for (n = 0; n < TXG_SIZE; n++) 523 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 524 #endif 525 children_dnodes[i] = NULL; 526 dnode_destroy(dn); 527 } 528 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 529 } 530 531 /* 532 * errors: 533 * EINVAL - invalid object number. 534 * EIO - i/o error. 535 * succeeds even for free dnodes. 536 */ 537 int 538 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 539 void *tag, dnode_t **dnp) 540 { 541 int epb, idx, err; 542 int drop_struct_lock = FALSE; 543 int type; 544 uint64_t blk; 545 dnode_t *mdn, *dn; 546 dmu_buf_impl_t *db; 547 dnode_t **children_dnodes; 548 549 /* 550 * If you are holding the spa config lock as writer, you shouldn't 551 * be asking the DMU to do *anything*. 552 */ 553 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0); 554 555 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 556 dn = (object == DMU_USERUSED_OBJECT) ? 557 os->os_userused_dnode : os->os_groupused_dnode; 558 if (dn == NULL) 559 return (ENOENT); 560 type = dn->dn_type; 561 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 562 return (ENOENT); 563 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 564 return (EEXIST); 565 DNODE_VERIFY(dn); 566 (void) refcount_add(&dn->dn_holds, tag); 567 *dnp = dn; 568 return (0); 569 } 570 571 if (object == 0 || object >= DN_MAX_OBJECT) 572 return (EINVAL); 573 574 mdn = os->os_meta_dnode; 575 576 DNODE_VERIFY(mdn); 577 578 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 579 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 580 drop_struct_lock = TRUE; 581 } 582 583 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 584 585 db = dbuf_hold(mdn, blk, FTAG); 586 if (drop_struct_lock) 587 rw_exit(&mdn->dn_struct_rwlock); 588 if (db == NULL) 589 return (EIO); 590 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 591 if (err) { 592 dbuf_rele(db, FTAG); 593 return (err); 594 } 595 596 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 597 epb = db->db.db_size >> DNODE_SHIFT; 598 599 idx = object & (epb-1); 600 601 children_dnodes = dmu_buf_get_user(&db->db); 602 if (children_dnodes == NULL) { 603 dnode_t **winner; 604 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 605 KM_SLEEP); 606 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 607 dnode_buf_pageout)) { 608 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 609 children_dnodes = winner; 610 } 611 } 612 613 if ((dn = children_dnodes[idx]) == NULL) { 614 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 615 dnode_t *winner; 616 617 dn = dnode_create(os, dnp, db, object); 618 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 619 if (winner != NULL) { 620 dnode_destroy(dn); 621 dn = winner; 622 } 623 } 624 625 mutex_enter(&dn->dn_mtx); 626 type = dn->dn_type; 627 if (dn->dn_free_txg || 628 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 629 ((flag & DNODE_MUST_BE_FREE) && 630 (type != DMU_OT_NONE || dn->dn_oldphys))) { 631 mutex_exit(&dn->dn_mtx); 632 dbuf_rele(db, FTAG); 633 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 634 } 635 mutex_exit(&dn->dn_mtx); 636 637 if (refcount_add(&dn->dn_holds, tag) == 1) 638 dbuf_add_ref(db, dn); 639 640 DNODE_VERIFY(dn); 641 ASSERT3P(dn->dn_dbuf, ==, db); 642 ASSERT3U(dn->dn_object, ==, object); 643 dbuf_rele(db, FTAG); 644 645 *dnp = dn; 646 return (0); 647 } 648 649 /* 650 * Return held dnode if the object is allocated, NULL if not. 651 */ 652 int 653 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 654 { 655 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 656 } 657 658 /* 659 * Can only add a reference if there is already at least one 660 * reference on the dnode. Returns FALSE if unable to add a 661 * new reference. 662 */ 663 boolean_t 664 dnode_add_ref(dnode_t *dn, void *tag) 665 { 666 mutex_enter(&dn->dn_mtx); 667 if (refcount_is_zero(&dn->dn_holds)) { 668 mutex_exit(&dn->dn_mtx); 669 return (FALSE); 670 } 671 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 672 mutex_exit(&dn->dn_mtx); 673 return (TRUE); 674 } 675 676 void 677 dnode_rele(dnode_t *dn, void *tag) 678 { 679 uint64_t refs; 680 681 mutex_enter(&dn->dn_mtx); 682 refs = refcount_remove(&dn->dn_holds, tag); 683 mutex_exit(&dn->dn_mtx); 684 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 685 if (refs == 0 && dn->dn_dbuf) 686 dbuf_rele(dn->dn_dbuf, dn); 687 } 688 689 void 690 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 691 { 692 objset_t *os = dn->dn_objset; 693 uint64_t txg = tx->tx_txg; 694 695 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 696 dsl_dataset_dirty(os->os_dsl_dataset, tx); 697 return; 698 } 699 700 DNODE_VERIFY(dn); 701 702 #ifdef ZFS_DEBUG 703 mutex_enter(&dn->dn_mtx); 704 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 705 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 706 mutex_exit(&dn->dn_mtx); 707 #endif 708 709 mutex_enter(&os->os_lock); 710 711 /* 712 * If we are already marked dirty, we're done. 713 */ 714 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 715 mutex_exit(&os->os_lock); 716 return; 717 } 718 719 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 720 ASSERT(dn->dn_datablksz != 0); 721 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 722 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 723 724 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 725 dn->dn_object, txg); 726 727 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 728 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 729 } else { 730 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 731 } 732 733 mutex_exit(&os->os_lock); 734 735 /* 736 * The dnode maintains a hold on its containing dbuf as 737 * long as there are holds on it. Each instantiated child 738 * dbuf maintaines a hold on the dnode. When the last child 739 * drops its hold, the dnode will drop its hold on the 740 * containing dbuf. We add a "dirty hold" here so that the 741 * dnode will hang around after we finish processing its 742 * children. 743 */ 744 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 745 746 (void) dbuf_dirty(dn->dn_dbuf, tx); 747 748 dsl_dataset_dirty(os->os_dsl_dataset, tx); 749 } 750 751 void 752 dnode_free(dnode_t *dn, dmu_tx_t *tx) 753 { 754 int txgoff = tx->tx_txg & TXG_MASK; 755 756 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 757 758 /* we should be the only holder... hopefully */ 759 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 760 761 mutex_enter(&dn->dn_mtx); 762 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 763 mutex_exit(&dn->dn_mtx); 764 return; 765 } 766 dn->dn_free_txg = tx->tx_txg; 767 mutex_exit(&dn->dn_mtx); 768 769 /* 770 * If the dnode is already dirty, it needs to be moved from 771 * the dirty list to the free list. 772 */ 773 mutex_enter(&dn->dn_objset->os_lock); 774 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 775 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 776 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 777 mutex_exit(&dn->dn_objset->os_lock); 778 } else { 779 mutex_exit(&dn->dn_objset->os_lock); 780 dnode_setdirty(dn, tx); 781 } 782 } 783 784 /* 785 * Try to change the block size for the indicated dnode. This can only 786 * succeed if there are no blocks allocated or dirty beyond first block 787 */ 788 int 789 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 790 { 791 dmu_buf_impl_t *db, *db_next; 792 int err; 793 794 if (size == 0) 795 size = SPA_MINBLOCKSIZE; 796 if (size > SPA_MAXBLOCKSIZE) 797 size = SPA_MAXBLOCKSIZE; 798 else 799 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 800 801 if (ibs == dn->dn_indblkshift) 802 ibs = 0; 803 804 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 805 return (0); 806 807 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 808 809 /* Check for any allocated blocks beyond the first */ 810 if (dn->dn_phys->dn_maxblkid != 0) 811 goto fail; 812 813 mutex_enter(&dn->dn_dbufs_mtx); 814 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 815 db_next = list_next(&dn->dn_dbufs, db); 816 817 if (db->db_blkid != 0 && db->db_blkid != DB_BONUS_BLKID) { 818 mutex_exit(&dn->dn_dbufs_mtx); 819 goto fail; 820 } 821 } 822 mutex_exit(&dn->dn_dbufs_mtx); 823 824 if (ibs && dn->dn_nlevels != 1) 825 goto fail; 826 827 /* resize the old block */ 828 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 829 if (err == 0) 830 dbuf_new_size(db, size, tx); 831 else if (err != ENOENT) 832 goto fail; 833 834 dnode_setdblksz(dn, size); 835 dnode_setdirty(dn, tx); 836 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 837 if (ibs) { 838 dn->dn_indblkshift = ibs; 839 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 840 } 841 /* rele after we have fixed the blocksize in the dnode */ 842 if (db) 843 dbuf_rele(db, FTAG); 844 845 rw_exit(&dn->dn_struct_rwlock); 846 return (0); 847 848 fail: 849 rw_exit(&dn->dn_struct_rwlock); 850 return (ENOTSUP); 851 } 852 853 /* read-holding callers must not rely on the lock being continuously held */ 854 void 855 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 856 { 857 uint64_t txgoff = tx->tx_txg & TXG_MASK; 858 int epbs, new_nlevels; 859 uint64_t sz; 860 861 ASSERT(blkid != DB_BONUS_BLKID); 862 863 ASSERT(have_read ? 864 RW_READ_HELD(&dn->dn_struct_rwlock) : 865 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 866 867 /* 868 * if we have a read-lock, check to see if we need to do any work 869 * before upgrading to a write-lock. 870 */ 871 if (have_read) { 872 if (blkid <= dn->dn_maxblkid) 873 return; 874 875 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 876 rw_exit(&dn->dn_struct_rwlock); 877 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 878 } 879 } 880 881 if (blkid <= dn->dn_maxblkid) 882 goto out; 883 884 dn->dn_maxblkid = blkid; 885 886 /* 887 * Compute the number of levels necessary to support the new maxblkid. 888 */ 889 new_nlevels = 1; 890 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 891 for (sz = dn->dn_nblkptr; 892 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 893 new_nlevels++; 894 895 if (new_nlevels > dn->dn_nlevels) { 896 int old_nlevels = dn->dn_nlevels; 897 dmu_buf_impl_t *db; 898 list_t *list; 899 dbuf_dirty_record_t *new, *dr, *dr_next; 900 901 dn->dn_nlevels = new_nlevels; 902 903 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 904 dn->dn_next_nlevels[txgoff] = new_nlevels; 905 906 /* dirty the left indirects */ 907 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 908 new = dbuf_dirty(db, tx); 909 dbuf_rele(db, FTAG); 910 911 /* transfer the dirty records to the new indirect */ 912 mutex_enter(&dn->dn_mtx); 913 mutex_enter(&new->dt.di.dr_mtx); 914 list = &dn->dn_dirty_records[txgoff]; 915 for (dr = list_head(list); dr; dr = dr_next) { 916 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 917 if (dr->dr_dbuf->db_level != new_nlevels-1 && 918 dr->dr_dbuf->db_blkid != DB_BONUS_BLKID) { 919 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 920 list_remove(&dn->dn_dirty_records[txgoff], dr); 921 list_insert_tail(&new->dt.di.dr_children, dr); 922 dr->dr_parent = new; 923 } 924 } 925 mutex_exit(&new->dt.di.dr_mtx); 926 mutex_exit(&dn->dn_mtx); 927 } 928 929 out: 930 if (have_read) 931 rw_downgrade(&dn->dn_struct_rwlock); 932 } 933 934 void 935 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 936 { 937 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 938 avl_index_t where; 939 free_range_t *rp; 940 free_range_t rp_tofind; 941 uint64_t endblk = blkid + nblks; 942 943 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 944 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 945 946 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 947 blkid, nblks, tx->tx_txg); 948 rp_tofind.fr_blkid = blkid; 949 rp = avl_find(tree, &rp_tofind, &where); 950 if (rp == NULL) 951 rp = avl_nearest(tree, where, AVL_BEFORE); 952 if (rp == NULL) 953 rp = avl_nearest(tree, where, AVL_AFTER); 954 955 while (rp && (rp->fr_blkid <= blkid + nblks)) { 956 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 957 free_range_t *nrp = AVL_NEXT(tree, rp); 958 959 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 960 /* clear this entire range */ 961 avl_remove(tree, rp); 962 kmem_free(rp, sizeof (free_range_t)); 963 } else if (blkid <= rp->fr_blkid && 964 endblk > rp->fr_blkid && endblk < fr_endblk) { 965 /* clear the beginning of this range */ 966 rp->fr_blkid = endblk; 967 rp->fr_nblks = fr_endblk - endblk; 968 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 969 endblk >= fr_endblk) { 970 /* clear the end of this range */ 971 rp->fr_nblks = blkid - rp->fr_blkid; 972 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 973 /* clear a chunk out of this range */ 974 free_range_t *new_rp = 975 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 976 977 new_rp->fr_blkid = endblk; 978 new_rp->fr_nblks = fr_endblk - endblk; 979 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 980 rp->fr_nblks = blkid - rp->fr_blkid; 981 } 982 /* there may be no overlap */ 983 rp = nrp; 984 } 985 } 986 987 void 988 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 989 { 990 dmu_buf_impl_t *db; 991 uint64_t blkoff, blkid, nblks; 992 int blksz, blkshift, head, tail; 993 int trunc = FALSE; 994 int epbs; 995 996 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 997 blksz = dn->dn_datablksz; 998 blkshift = dn->dn_datablkshift; 999 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1000 1001 if (len == -1ULL) { 1002 len = UINT64_MAX - off; 1003 trunc = TRUE; 1004 } 1005 1006 /* 1007 * First, block align the region to free: 1008 */ 1009 if (ISP2(blksz)) { 1010 head = P2NPHASE(off, blksz); 1011 blkoff = P2PHASE(off, blksz); 1012 if ((off >> blkshift) > dn->dn_maxblkid) 1013 goto out; 1014 } else { 1015 ASSERT(dn->dn_maxblkid == 0); 1016 if (off == 0 && len >= blksz) { 1017 /* Freeing the whole block; fast-track this request */ 1018 blkid = 0; 1019 nblks = 1; 1020 goto done; 1021 } else if (off >= blksz) { 1022 /* Freeing past end-of-data */ 1023 goto out; 1024 } else { 1025 /* Freeing part of the block. */ 1026 head = blksz - off; 1027 ASSERT3U(head, >, 0); 1028 } 1029 blkoff = off; 1030 } 1031 /* zero out any partial block data at the start of the range */ 1032 if (head) { 1033 ASSERT3U(blkoff + head, ==, blksz); 1034 if (len < head) 1035 head = len; 1036 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1037 FTAG, &db) == 0) { 1038 caddr_t data; 1039 1040 /* don't dirty if it isn't on disk and isn't dirty */ 1041 if (db->db_last_dirty || 1042 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1043 rw_exit(&dn->dn_struct_rwlock); 1044 dbuf_will_dirty(db, tx); 1045 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1046 data = db->db.db_data; 1047 bzero(data + blkoff, head); 1048 } 1049 dbuf_rele(db, FTAG); 1050 } 1051 off += head; 1052 len -= head; 1053 } 1054 1055 /* If the range was less than one block, we're done */ 1056 if (len == 0) 1057 goto out; 1058 1059 /* If the remaining range is past end of file, we're done */ 1060 if ((off >> blkshift) > dn->dn_maxblkid) 1061 goto out; 1062 1063 ASSERT(ISP2(blksz)); 1064 if (trunc) 1065 tail = 0; 1066 else 1067 tail = P2PHASE(len, blksz); 1068 1069 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1070 /* zero out any partial block data at the end of the range */ 1071 if (tail) { 1072 if (len < tail) 1073 tail = len; 1074 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1075 TRUE, FTAG, &db) == 0) { 1076 /* don't dirty if not on disk and not dirty */ 1077 if (db->db_last_dirty || 1078 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1079 rw_exit(&dn->dn_struct_rwlock); 1080 dbuf_will_dirty(db, tx); 1081 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1082 bzero(db->db.db_data, tail); 1083 } 1084 dbuf_rele(db, FTAG); 1085 } 1086 len -= tail; 1087 } 1088 1089 /* If the range did not include a full block, we are done */ 1090 if (len == 0) 1091 goto out; 1092 1093 ASSERT(IS_P2ALIGNED(off, blksz)); 1094 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1095 blkid = off >> blkshift; 1096 nblks = len >> blkshift; 1097 if (trunc) 1098 nblks += 1; 1099 1100 /* 1101 * Read in and mark all the level-1 indirects dirty, 1102 * so that they will stay in memory until syncing phase. 1103 * Always dirty the first and last indirect to make sure 1104 * we dirty all the partial indirects. 1105 */ 1106 if (dn->dn_nlevels > 1) { 1107 uint64_t i, first, last; 1108 int shift = epbs + dn->dn_datablkshift; 1109 1110 first = blkid >> epbs; 1111 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1112 dbuf_will_dirty(db, tx); 1113 dbuf_rele(db, FTAG); 1114 } 1115 if (trunc) 1116 last = dn->dn_maxblkid >> epbs; 1117 else 1118 last = (blkid + nblks - 1) >> epbs; 1119 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1120 dbuf_will_dirty(db, tx); 1121 dbuf_rele(db, FTAG); 1122 } 1123 for (i = first + 1; i < last; i++) { 1124 uint64_t ibyte = i << shift; 1125 int err; 1126 1127 err = dnode_next_offset(dn, 1128 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1129 i = ibyte >> shift; 1130 if (err == ESRCH || i >= last) 1131 break; 1132 ASSERT(err == 0); 1133 db = dbuf_hold_level(dn, 1, i, FTAG); 1134 if (db) { 1135 dbuf_will_dirty(db, tx); 1136 dbuf_rele(db, FTAG); 1137 } 1138 } 1139 } 1140 done: 1141 /* 1142 * Add this range to the dnode range list. 1143 * We will finish up this free operation in the syncing phase. 1144 */ 1145 mutex_enter(&dn->dn_mtx); 1146 dnode_clear_range(dn, blkid, nblks, tx); 1147 { 1148 free_range_t *rp, *found; 1149 avl_index_t where; 1150 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1151 1152 /* Add new range to dn_ranges */ 1153 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1154 rp->fr_blkid = blkid; 1155 rp->fr_nblks = nblks; 1156 found = avl_find(tree, rp, &where); 1157 ASSERT(found == NULL); 1158 avl_insert(tree, rp, where); 1159 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1160 blkid, nblks, tx->tx_txg); 1161 } 1162 mutex_exit(&dn->dn_mtx); 1163 1164 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1165 dnode_setdirty(dn, tx); 1166 out: 1167 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1168 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1169 1170 rw_exit(&dn->dn_struct_rwlock); 1171 } 1172 1173 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1174 uint64_t 1175 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1176 { 1177 free_range_t range_tofind; 1178 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1179 int i; 1180 1181 if (blkid == DB_BONUS_BLKID) 1182 return (FALSE); 1183 1184 /* 1185 * If we're in the process of opening the pool, dp will not be 1186 * set yet, but there shouldn't be anything dirty. 1187 */ 1188 if (dp == NULL) 1189 return (FALSE); 1190 1191 if (dn->dn_free_txg) 1192 return (TRUE); 1193 1194 range_tofind.fr_blkid = blkid; 1195 mutex_enter(&dn->dn_mtx); 1196 for (i = 0; i < TXG_SIZE; i++) { 1197 free_range_t *range_found; 1198 avl_index_t idx; 1199 1200 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1201 if (range_found) { 1202 ASSERT(range_found->fr_nblks > 0); 1203 break; 1204 } 1205 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1206 if (range_found && 1207 range_found->fr_blkid + range_found->fr_nblks > blkid) 1208 break; 1209 } 1210 mutex_exit(&dn->dn_mtx); 1211 return (i < TXG_SIZE); 1212 } 1213 1214 /* call from syncing context when we actually write/free space for this dnode */ 1215 void 1216 dnode_diduse_space(dnode_t *dn, int64_t delta) 1217 { 1218 uint64_t space; 1219 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1220 dn, dn->dn_phys, 1221 (u_longlong_t)dn->dn_phys->dn_used, 1222 (longlong_t)delta); 1223 1224 mutex_enter(&dn->dn_mtx); 1225 space = DN_USED_BYTES(dn->dn_phys); 1226 if (delta > 0) { 1227 ASSERT3U(space + delta, >=, space); /* no overflow */ 1228 } else { 1229 ASSERT3U(space, >=, -delta); /* no underflow */ 1230 } 1231 space += delta; 1232 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1233 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1234 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1235 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1236 } else { 1237 dn->dn_phys->dn_used = space; 1238 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1239 } 1240 mutex_exit(&dn->dn_mtx); 1241 } 1242 1243 /* 1244 * Call when we think we're going to write/free space in open context. 1245 * Be conservative (ie. OK to write less than this or free more than 1246 * this, but don't write more or free less). 1247 */ 1248 void 1249 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1250 { 1251 objset_t *os = dn->dn_objset; 1252 dsl_dataset_t *ds = os->os_dsl_dataset; 1253 1254 if (space > 0) 1255 space = spa_get_asize(os->os_spa, space); 1256 1257 if (ds) 1258 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1259 1260 dmu_tx_willuse_space(tx, space); 1261 } 1262 1263 /* 1264 * This function scans a block at the indicated "level" looking for 1265 * a hole or data (depending on 'flags'). If level > 0, then we are 1266 * scanning an indirect block looking at its pointers. If level == 0, 1267 * then we are looking at a block of dnodes. If we don't find what we 1268 * are looking for in the block, we return ESRCH. Otherwise, return 1269 * with *offset pointing to the beginning (if searching forwards) or 1270 * end (if searching backwards) of the range covered by the block 1271 * pointer we matched on (or dnode). 1272 * 1273 * The basic search algorithm used below by dnode_next_offset() is to 1274 * use this function to search up the block tree (widen the search) until 1275 * we find something (i.e., we don't return ESRCH) and then search back 1276 * down the tree (narrow the search) until we reach our original search 1277 * level. 1278 */ 1279 static int 1280 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1281 int lvl, uint64_t blkfill, uint64_t txg) 1282 { 1283 dmu_buf_impl_t *db = NULL; 1284 void *data = NULL; 1285 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1286 uint64_t epb = 1ULL << epbs; 1287 uint64_t minfill, maxfill; 1288 boolean_t hole; 1289 int i, inc, error, span; 1290 1291 dprintf("probing object %llu offset %llx level %d of %u\n", 1292 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1293 1294 hole = ((flags & DNODE_FIND_HOLE) != 0); 1295 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1296 ASSERT(txg == 0 || !hole); 1297 1298 if (lvl == dn->dn_phys->dn_nlevels) { 1299 error = 0; 1300 epb = dn->dn_phys->dn_nblkptr; 1301 data = dn->dn_phys->dn_blkptr; 1302 } else { 1303 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1304 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1305 if (error) { 1306 if (error != ENOENT) 1307 return (error); 1308 if (hole) 1309 return (0); 1310 /* 1311 * This can only happen when we are searching up 1312 * the block tree for data. We don't really need to 1313 * adjust the offset, as we will just end up looking 1314 * at the pointer to this block in its parent, and its 1315 * going to be unallocated, so we will skip over it. 1316 */ 1317 return (ESRCH); 1318 } 1319 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1320 if (error) { 1321 dbuf_rele(db, FTAG); 1322 return (error); 1323 } 1324 data = db->db.db_data; 1325 } 1326 1327 if (db && txg && 1328 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1329 /* 1330 * This can only happen when we are searching up the tree 1331 * and these conditions mean that we need to keep climbing. 1332 */ 1333 error = ESRCH; 1334 } else if (lvl == 0) { 1335 dnode_phys_t *dnp = data; 1336 span = DNODE_SHIFT; 1337 ASSERT(dn->dn_type == DMU_OT_DNODE); 1338 1339 for (i = (*offset >> span) & (blkfill - 1); 1340 i >= 0 && i < blkfill; i += inc) { 1341 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1342 break; 1343 *offset += (1ULL << span) * inc; 1344 } 1345 if (i < 0 || i == blkfill) 1346 error = ESRCH; 1347 } else { 1348 blkptr_t *bp = data; 1349 uint64_t start = *offset; 1350 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1351 minfill = 0; 1352 maxfill = blkfill << ((lvl - 1) * epbs); 1353 1354 if (hole) 1355 maxfill--; 1356 else 1357 minfill++; 1358 1359 *offset = *offset >> span; 1360 for (i = BF64_GET(*offset, 0, epbs); 1361 i >= 0 && i < epb; i += inc) { 1362 if (bp[i].blk_fill >= minfill && 1363 bp[i].blk_fill <= maxfill && 1364 (hole || bp[i].blk_birth > txg)) 1365 break; 1366 if (inc > 0 || *offset > 0) 1367 *offset += inc; 1368 } 1369 *offset = *offset << span; 1370 if (inc < 0) { 1371 /* traversing backwards; position offset at the end */ 1372 ASSERT3U(*offset, <=, start); 1373 *offset = MIN(*offset + (1ULL << span) - 1, start); 1374 } else if (*offset < start) { 1375 *offset = start; 1376 } 1377 if (i < 0 || i >= epb) 1378 error = ESRCH; 1379 } 1380 1381 if (db) 1382 dbuf_rele(db, FTAG); 1383 1384 return (error); 1385 } 1386 1387 /* 1388 * Find the next hole, data, or sparse region at or after *offset. 1389 * The value 'blkfill' tells us how many items we expect to find 1390 * in an L0 data block; this value is 1 for normal objects, 1391 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1392 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1393 * 1394 * Examples: 1395 * 1396 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1397 * Finds the next/previous hole/data in a file. 1398 * Used in dmu_offset_next(). 1399 * 1400 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1401 * Finds the next free/allocated dnode an objset's meta-dnode. 1402 * Only finds objects that have new contents since txg (ie. 1403 * bonus buffer changes and content removal are ignored). 1404 * Used in dmu_object_next(). 1405 * 1406 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1407 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1408 * Used in dmu_object_alloc(). 1409 */ 1410 int 1411 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1412 int minlvl, uint64_t blkfill, uint64_t txg) 1413 { 1414 uint64_t initial_offset = *offset; 1415 int lvl, maxlvl; 1416 int error = 0; 1417 1418 if (!(flags & DNODE_FIND_HAVELOCK)) 1419 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1420 1421 if (dn->dn_phys->dn_nlevels == 0) { 1422 error = ESRCH; 1423 goto out; 1424 } 1425 1426 if (dn->dn_datablkshift == 0) { 1427 if (*offset < dn->dn_datablksz) { 1428 if (flags & DNODE_FIND_HOLE) 1429 *offset = dn->dn_datablksz; 1430 } else { 1431 error = ESRCH; 1432 } 1433 goto out; 1434 } 1435 1436 maxlvl = dn->dn_phys->dn_nlevels; 1437 1438 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1439 error = dnode_next_offset_level(dn, 1440 flags, offset, lvl, blkfill, txg); 1441 if (error != ESRCH) 1442 break; 1443 } 1444 1445 while (error == 0 && --lvl >= minlvl) { 1446 error = dnode_next_offset_level(dn, 1447 flags, offset, lvl, blkfill, txg); 1448 } 1449 1450 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1451 initial_offset < *offset : initial_offset > *offset)) 1452 error = ESRCH; 1453 out: 1454 if (!(flags & DNODE_FIND_HAVELOCK)) 1455 rw_exit(&dn->dn_struct_rwlock); 1456 1457 return (error); 1458 } 1459