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(dn->dn_object == DMU_META_DNODE_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_impl_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_impl_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 324 325 mutex_enter(&os->os_lock); 326 list_remove(&os->os_dnodes, dn); 327 mutex_exit(&os->os_lock); 328 329 if (dn->dn_dirtyctx_firstset) { 330 kmem_free(dn->dn_dirtyctx_firstset, 1); 331 dn->dn_dirtyctx_firstset = NULL; 332 } 333 dmu_zfetch_rele(&dn->dn_zfetch); 334 if (dn->dn_bonus) { 335 mutex_enter(&dn->dn_bonus->db_mtx); 336 dbuf_evict(dn->dn_bonus); 337 dn->dn_bonus = NULL; 338 } 339 kmem_cache_free(dnode_cache, dn); 340 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 341 } 342 343 void 344 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 345 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 346 { 347 int i; 348 349 if (blocksize == 0) 350 blocksize = 1 << zfs_default_bs; 351 else if (blocksize > SPA_MAXBLOCKSIZE) 352 blocksize = SPA_MAXBLOCKSIZE; 353 else 354 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 355 356 if (ibs == 0) 357 ibs = zfs_default_ibs; 358 359 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 360 361 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 362 dn->dn_object, tx->tx_txg, blocksize, ibs); 363 364 ASSERT(dn->dn_type == DMU_OT_NONE); 365 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 366 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 367 ASSERT(ot != DMU_OT_NONE); 368 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 369 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 370 (bonustype != DMU_OT_NONE && bonuslen != 0)); 371 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 372 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 373 ASSERT(dn->dn_type == DMU_OT_NONE); 374 ASSERT3U(dn->dn_maxblkid, ==, 0); 375 ASSERT3U(dn->dn_allocated_txg, ==, 0); 376 ASSERT3U(dn->dn_assigned_txg, ==, 0); 377 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 378 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 379 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 380 381 for (i = 0; i < TXG_SIZE; i++) { 382 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 383 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 384 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 385 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 386 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 387 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 388 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 389 } 390 391 dn->dn_type = ot; 392 dnode_setdblksz(dn, blocksize); 393 dn->dn_indblkshift = ibs; 394 dn->dn_nlevels = 1; 395 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 396 dn->dn_bonustype = bonustype; 397 dn->dn_bonuslen = bonuslen; 398 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 399 dn->dn_compress = ZIO_COMPRESS_INHERIT; 400 dn->dn_dirtyctx = 0; 401 402 dn->dn_free_txg = 0; 403 if (dn->dn_dirtyctx_firstset) { 404 kmem_free(dn->dn_dirtyctx_firstset, 1); 405 dn->dn_dirtyctx_firstset = NULL; 406 } 407 408 dn->dn_allocated_txg = tx->tx_txg; 409 410 dnode_setdirty(dn, tx); 411 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 412 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 413 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 414 } 415 416 void 417 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 418 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 419 { 420 int nblkptr; 421 422 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 423 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 424 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 425 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 426 ASSERT(tx->tx_txg != 0); 427 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 428 (bonustype != DMU_OT_NONE && bonuslen != 0)); 429 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 430 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 431 432 /* clean up any unreferenced dbufs */ 433 dnode_evict_dbufs(dn); 434 435 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 436 dnode_setdirty(dn, tx); 437 if (dn->dn_datablksz != blocksize) { 438 /* change blocksize */ 439 ASSERT(dn->dn_maxblkid == 0 && 440 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 441 dnode_block_freed(dn, 0))); 442 dnode_setdblksz(dn, blocksize); 443 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 444 } 445 if (dn->dn_bonuslen != bonuslen) 446 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 447 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 448 if (dn->dn_nblkptr != nblkptr) 449 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 450 rw_exit(&dn->dn_struct_rwlock); 451 452 /* change type */ 453 dn->dn_type = ot; 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 = nblkptr; 460 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 461 dn->dn_compress = ZIO_COMPRESS_INHERIT; 462 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 463 464 /* fix up the bonus db_size */ 465 if (dn->dn_bonus) { 466 dn->dn_bonus->db.db_size = 467 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 468 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 469 } 470 471 dn->dn_allocated_txg = tx->tx_txg; 472 mutex_exit(&dn->dn_mtx); 473 } 474 475 void 476 dnode_special_close(dnode_t *dn) 477 { 478 /* 479 * Wait for final references to the dnode to clear. This can 480 * only happen if the arc is asyncronously evicting state that 481 * has a hold on this dnode while we are trying to evict this 482 * dnode. 483 */ 484 while (refcount_count(&dn->dn_holds) > 0) 485 delay(1); 486 dnode_destroy(dn); 487 } 488 489 dnode_t * 490 dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 491 { 492 dnode_t *dn = dnode_create(os, dnp, NULL, object); 493 DNODE_VERIFY(dn); 494 return (dn); 495 } 496 497 static void 498 dnode_buf_pageout(dmu_buf_t *db, void *arg) 499 { 500 dnode_t **children_dnodes = arg; 501 int i; 502 int epb = db->db_size >> DNODE_SHIFT; 503 504 for (i = 0; i < epb; i++) { 505 dnode_t *dn = children_dnodes[i]; 506 int n; 507 508 if (dn == NULL) 509 continue; 510 #ifdef ZFS_DEBUG 511 /* 512 * If there are holds on this dnode, then there should 513 * be holds on the dnode's containing dbuf as well; thus 514 * it wouldn't be eligable for eviction and this function 515 * would not have been called. 516 */ 517 ASSERT(refcount_is_zero(&dn->dn_holds)); 518 ASSERT(list_head(&dn->dn_dbufs) == NULL); 519 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 520 521 for (n = 0; n < TXG_SIZE; n++) 522 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 523 #endif 524 children_dnodes[i] = NULL; 525 dnode_destroy(dn); 526 } 527 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 528 } 529 530 /* 531 * errors: 532 * EINVAL - invalid object number. 533 * EIO - i/o error. 534 * succeeds even for free dnodes. 535 */ 536 int 537 dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 538 void *tag, dnode_t **dnp) 539 { 540 int epb, idx, err; 541 int drop_struct_lock = FALSE; 542 int type; 543 uint64_t blk; 544 dnode_t *mdn, *dn; 545 dmu_buf_impl_t *db; 546 dnode_t **children_dnodes; 547 548 /* 549 * If you are holding the spa config lock as writer, you shouldn't 550 * be asking the DMU to do *anything*. 551 */ 552 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0); 553 554 if (object == 0 || object >= DN_MAX_OBJECT) 555 return (EINVAL); 556 557 mdn = os->os_meta_dnode; 558 559 DNODE_VERIFY(mdn); 560 561 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 562 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 563 drop_struct_lock = TRUE; 564 } 565 566 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 567 568 db = dbuf_hold(mdn, blk, FTAG); 569 if (drop_struct_lock) 570 rw_exit(&mdn->dn_struct_rwlock); 571 if (db == NULL) 572 return (EIO); 573 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 574 if (err) { 575 dbuf_rele(db, FTAG); 576 return (err); 577 } 578 579 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 580 epb = db->db.db_size >> DNODE_SHIFT; 581 582 idx = object & (epb-1); 583 584 children_dnodes = dmu_buf_get_user(&db->db); 585 if (children_dnodes == NULL) { 586 dnode_t **winner; 587 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 588 KM_SLEEP); 589 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 590 dnode_buf_pageout)) { 591 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 592 children_dnodes = winner; 593 } 594 } 595 596 if ((dn = children_dnodes[idx]) == NULL) { 597 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 598 dnode_t *winner; 599 600 dn = dnode_create(os, dnp, db, object); 601 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 602 if (winner != NULL) { 603 dnode_destroy(dn); 604 dn = winner; 605 } 606 } 607 608 mutex_enter(&dn->dn_mtx); 609 type = dn->dn_type; 610 if (dn->dn_free_txg || 611 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 612 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 613 mutex_exit(&dn->dn_mtx); 614 dbuf_rele(db, FTAG); 615 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 616 } 617 mutex_exit(&dn->dn_mtx); 618 619 if (refcount_add(&dn->dn_holds, tag) == 1) 620 dbuf_add_ref(db, dn); 621 622 DNODE_VERIFY(dn); 623 ASSERT3P(dn->dn_dbuf, ==, db); 624 ASSERT3U(dn->dn_object, ==, object); 625 dbuf_rele(db, FTAG); 626 627 *dnp = dn; 628 return (0); 629 } 630 631 /* 632 * Return held dnode if the object is allocated, NULL if not. 633 */ 634 int 635 dnode_hold(objset_impl_t *os, uint64_t object, void *tag, dnode_t **dnp) 636 { 637 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 638 } 639 640 /* 641 * Can only add a reference if there is already at least one 642 * reference on the dnode. Returns FALSE if unable to add a 643 * new reference. 644 */ 645 boolean_t 646 dnode_add_ref(dnode_t *dn, void *tag) 647 { 648 mutex_enter(&dn->dn_mtx); 649 if (refcount_is_zero(&dn->dn_holds)) { 650 mutex_exit(&dn->dn_mtx); 651 return (FALSE); 652 } 653 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 654 mutex_exit(&dn->dn_mtx); 655 return (TRUE); 656 } 657 658 void 659 dnode_rele(dnode_t *dn, void *tag) 660 { 661 uint64_t refs; 662 663 mutex_enter(&dn->dn_mtx); 664 refs = refcount_remove(&dn->dn_holds, tag); 665 mutex_exit(&dn->dn_mtx); 666 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 667 if (refs == 0 && dn->dn_dbuf) 668 dbuf_rele(dn->dn_dbuf, dn); 669 } 670 671 void 672 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 673 { 674 objset_impl_t *os = dn->dn_objset; 675 uint64_t txg = tx->tx_txg; 676 677 if (dn->dn_object == DMU_META_DNODE_OBJECT) 678 return; 679 680 DNODE_VERIFY(dn); 681 682 #ifdef ZFS_DEBUG 683 mutex_enter(&dn->dn_mtx); 684 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 685 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 686 mutex_exit(&dn->dn_mtx); 687 #endif 688 689 mutex_enter(&os->os_lock); 690 691 /* 692 * If we are already marked dirty, we're done. 693 */ 694 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 695 mutex_exit(&os->os_lock); 696 return; 697 } 698 699 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 700 ASSERT(dn->dn_datablksz != 0); 701 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 702 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 703 704 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 705 dn->dn_object, txg); 706 707 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 708 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 709 } else { 710 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 711 } 712 713 mutex_exit(&os->os_lock); 714 715 /* 716 * The dnode maintains a hold on its containing dbuf as 717 * long as there are holds on it. Each instantiated child 718 * dbuf maintaines a hold on the dnode. When the last child 719 * drops its hold, the dnode will drop its hold on the 720 * containing dbuf. We add a "dirty hold" here so that the 721 * dnode will hang around after we finish processing its 722 * children. 723 */ 724 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 725 726 (void) dbuf_dirty(dn->dn_dbuf, tx); 727 728 dsl_dataset_dirty(os->os_dsl_dataset, tx); 729 } 730 731 void 732 dnode_free(dnode_t *dn, dmu_tx_t *tx) 733 { 734 int txgoff = tx->tx_txg & TXG_MASK; 735 736 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 737 738 /* we should be the only holder... hopefully */ 739 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 740 741 mutex_enter(&dn->dn_mtx); 742 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 743 mutex_exit(&dn->dn_mtx); 744 return; 745 } 746 dn->dn_free_txg = tx->tx_txg; 747 mutex_exit(&dn->dn_mtx); 748 749 /* 750 * If the dnode is already dirty, it needs to be moved from 751 * the dirty list to the free list. 752 */ 753 mutex_enter(&dn->dn_objset->os_lock); 754 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 755 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 756 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 757 mutex_exit(&dn->dn_objset->os_lock); 758 } else { 759 mutex_exit(&dn->dn_objset->os_lock); 760 dnode_setdirty(dn, tx); 761 } 762 } 763 764 /* 765 * Try to change the block size for the indicated dnode. This can only 766 * succeed if there are no blocks allocated or dirty beyond first block 767 */ 768 int 769 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 770 { 771 dmu_buf_impl_t *db, *db_next; 772 int err; 773 774 if (size == 0) 775 size = SPA_MINBLOCKSIZE; 776 if (size > SPA_MAXBLOCKSIZE) 777 size = SPA_MAXBLOCKSIZE; 778 else 779 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 780 781 if (ibs == dn->dn_indblkshift) 782 ibs = 0; 783 784 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 785 return (0); 786 787 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 788 789 /* Check for any allocated blocks beyond the first */ 790 if (dn->dn_phys->dn_maxblkid != 0) 791 goto fail; 792 793 mutex_enter(&dn->dn_dbufs_mtx); 794 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 795 db_next = list_next(&dn->dn_dbufs, db); 796 797 if (db->db_blkid != 0 && db->db_blkid != DB_BONUS_BLKID) { 798 mutex_exit(&dn->dn_dbufs_mtx); 799 goto fail; 800 } 801 } 802 mutex_exit(&dn->dn_dbufs_mtx); 803 804 if (ibs && dn->dn_nlevels != 1) 805 goto fail; 806 807 /* resize the old block */ 808 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 809 if (err == 0) 810 dbuf_new_size(db, size, tx); 811 else if (err != ENOENT) 812 goto fail; 813 814 dnode_setdblksz(dn, size); 815 dnode_setdirty(dn, tx); 816 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 817 if (ibs) { 818 dn->dn_indblkshift = ibs; 819 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 820 } 821 /* rele after we have fixed the blocksize in the dnode */ 822 if (db) 823 dbuf_rele(db, FTAG); 824 825 rw_exit(&dn->dn_struct_rwlock); 826 return (0); 827 828 fail: 829 rw_exit(&dn->dn_struct_rwlock); 830 return (ENOTSUP); 831 } 832 833 /* read-holding callers must not rely on the lock being continuously held */ 834 void 835 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 836 { 837 uint64_t txgoff = tx->tx_txg & TXG_MASK; 838 int epbs, new_nlevels; 839 uint64_t sz; 840 841 ASSERT(blkid != DB_BONUS_BLKID); 842 843 ASSERT(have_read ? 844 RW_READ_HELD(&dn->dn_struct_rwlock) : 845 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 846 847 /* 848 * if we have a read-lock, check to see if we need to do any work 849 * before upgrading to a write-lock. 850 */ 851 if (have_read) { 852 if (blkid <= dn->dn_maxblkid) 853 return; 854 855 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 856 rw_exit(&dn->dn_struct_rwlock); 857 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 858 } 859 } 860 861 if (blkid <= dn->dn_maxblkid) 862 goto out; 863 864 dn->dn_maxblkid = blkid; 865 866 /* 867 * Compute the number of levels necessary to support the new maxblkid. 868 */ 869 new_nlevels = 1; 870 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 871 for (sz = dn->dn_nblkptr; 872 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 873 new_nlevels++; 874 875 if (new_nlevels > dn->dn_nlevels) { 876 int old_nlevels = dn->dn_nlevels; 877 dmu_buf_impl_t *db; 878 list_t *list; 879 dbuf_dirty_record_t *new, *dr, *dr_next; 880 881 dn->dn_nlevels = new_nlevels; 882 883 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 884 dn->dn_next_nlevels[txgoff] = new_nlevels; 885 886 /* dirty the left indirects */ 887 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 888 new = dbuf_dirty(db, tx); 889 dbuf_rele(db, FTAG); 890 891 /* transfer the dirty records to the new indirect */ 892 mutex_enter(&dn->dn_mtx); 893 mutex_enter(&new->dt.di.dr_mtx); 894 list = &dn->dn_dirty_records[txgoff]; 895 for (dr = list_head(list); dr; dr = dr_next) { 896 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 897 if (dr->dr_dbuf->db_level != new_nlevels-1 && 898 dr->dr_dbuf->db_blkid != DB_BONUS_BLKID) { 899 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 900 list_remove(&dn->dn_dirty_records[txgoff], dr); 901 list_insert_tail(&new->dt.di.dr_children, dr); 902 dr->dr_parent = new; 903 } 904 } 905 mutex_exit(&new->dt.di.dr_mtx); 906 mutex_exit(&dn->dn_mtx); 907 } 908 909 out: 910 if (have_read) 911 rw_downgrade(&dn->dn_struct_rwlock); 912 } 913 914 void 915 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 916 { 917 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 918 avl_index_t where; 919 free_range_t *rp; 920 free_range_t rp_tofind; 921 uint64_t endblk = blkid + nblks; 922 923 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 924 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 925 926 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 927 blkid, nblks, tx->tx_txg); 928 rp_tofind.fr_blkid = blkid; 929 rp = avl_find(tree, &rp_tofind, &where); 930 if (rp == NULL) 931 rp = avl_nearest(tree, where, AVL_BEFORE); 932 if (rp == NULL) 933 rp = avl_nearest(tree, where, AVL_AFTER); 934 935 while (rp && (rp->fr_blkid <= blkid + nblks)) { 936 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 937 free_range_t *nrp = AVL_NEXT(tree, rp); 938 939 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 940 /* clear this entire range */ 941 avl_remove(tree, rp); 942 kmem_free(rp, sizeof (free_range_t)); 943 } else if (blkid <= rp->fr_blkid && 944 endblk > rp->fr_blkid && endblk < fr_endblk) { 945 /* clear the beginning of this range */ 946 rp->fr_blkid = endblk; 947 rp->fr_nblks = fr_endblk - endblk; 948 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 949 endblk >= fr_endblk) { 950 /* clear the end of this range */ 951 rp->fr_nblks = blkid - rp->fr_blkid; 952 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 953 /* clear a chunk out of this range */ 954 free_range_t *new_rp = 955 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 956 957 new_rp->fr_blkid = endblk; 958 new_rp->fr_nblks = fr_endblk - endblk; 959 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 960 rp->fr_nblks = blkid - rp->fr_blkid; 961 } 962 /* there may be no overlap */ 963 rp = nrp; 964 } 965 } 966 967 void 968 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 969 { 970 dmu_buf_impl_t *db; 971 uint64_t blkoff, blkid, nblks; 972 int blksz, blkshift, head, tail; 973 int trunc = FALSE; 974 int epbs; 975 976 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 977 blksz = dn->dn_datablksz; 978 blkshift = dn->dn_datablkshift; 979 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 980 981 if (len == -1ULL) { 982 len = UINT64_MAX - off; 983 trunc = TRUE; 984 } 985 986 /* 987 * First, block align the region to free: 988 */ 989 if (ISP2(blksz)) { 990 head = P2NPHASE(off, blksz); 991 blkoff = P2PHASE(off, blksz); 992 if ((off >> blkshift) > dn->dn_maxblkid) 993 goto out; 994 } else { 995 ASSERT(dn->dn_maxblkid == 0); 996 if (off == 0 && len >= blksz) { 997 /* Freeing the whole block; fast-track this request */ 998 blkid = 0; 999 nblks = 1; 1000 goto done; 1001 } else if (off >= blksz) { 1002 /* Freeing past end-of-data */ 1003 goto out; 1004 } else { 1005 /* Freeing part of the block. */ 1006 head = blksz - off; 1007 ASSERT3U(head, >, 0); 1008 } 1009 blkoff = off; 1010 } 1011 /* zero out any partial block data at the start of the range */ 1012 if (head) { 1013 ASSERT3U(blkoff + head, ==, blksz); 1014 if (len < head) 1015 head = len; 1016 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1017 FTAG, &db) == 0) { 1018 caddr_t data; 1019 1020 /* don't dirty if it isn't on disk and isn't dirty */ 1021 if (db->db_last_dirty || 1022 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1023 rw_exit(&dn->dn_struct_rwlock); 1024 dbuf_will_dirty(db, tx); 1025 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1026 data = db->db.db_data; 1027 bzero(data + blkoff, head); 1028 } 1029 dbuf_rele(db, FTAG); 1030 } 1031 off += head; 1032 len -= head; 1033 } 1034 1035 /* If the range was less than one block, we're done */ 1036 if (len == 0) 1037 goto out; 1038 1039 /* If the remaining range is past end of file, we're done */ 1040 if ((off >> blkshift) > dn->dn_maxblkid) 1041 goto out; 1042 1043 ASSERT(ISP2(blksz)); 1044 if (trunc) 1045 tail = 0; 1046 else 1047 tail = P2PHASE(len, blksz); 1048 1049 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1050 /* zero out any partial block data at the end of the range */ 1051 if (tail) { 1052 if (len < tail) 1053 tail = len; 1054 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1055 TRUE, FTAG, &db) == 0) { 1056 /* don't dirty if not on disk and not dirty */ 1057 if (db->db_last_dirty || 1058 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1059 rw_exit(&dn->dn_struct_rwlock); 1060 dbuf_will_dirty(db, tx); 1061 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1062 bzero(db->db.db_data, tail); 1063 } 1064 dbuf_rele(db, FTAG); 1065 } 1066 len -= tail; 1067 } 1068 1069 /* If the range did not include a full block, we are done */ 1070 if (len == 0) 1071 goto out; 1072 1073 ASSERT(IS_P2ALIGNED(off, blksz)); 1074 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1075 blkid = off >> blkshift; 1076 nblks = len >> blkshift; 1077 if (trunc) 1078 nblks += 1; 1079 1080 /* 1081 * Read in and mark all the level-1 indirects dirty, 1082 * so that they will stay in memory until syncing phase. 1083 * Always dirty the first and last indirect to make sure 1084 * we dirty all the partial indirects. 1085 */ 1086 if (dn->dn_nlevels > 1) { 1087 uint64_t i, first, last; 1088 int shift = epbs + dn->dn_datablkshift; 1089 1090 first = blkid >> epbs; 1091 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1092 dbuf_will_dirty(db, tx); 1093 dbuf_rele(db, FTAG); 1094 } 1095 if (trunc) 1096 last = dn->dn_maxblkid >> epbs; 1097 else 1098 last = (blkid + nblks - 1) >> epbs; 1099 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1100 dbuf_will_dirty(db, tx); 1101 dbuf_rele(db, FTAG); 1102 } 1103 for (i = first + 1; i < last; i++) { 1104 uint64_t ibyte = i << shift; 1105 int err; 1106 1107 err = dnode_next_offset(dn, 1108 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1109 i = ibyte >> shift; 1110 if (err == ESRCH || i >= last) 1111 break; 1112 ASSERT(err == 0); 1113 db = dbuf_hold_level(dn, 1, i, FTAG); 1114 if (db) { 1115 dbuf_will_dirty(db, tx); 1116 dbuf_rele(db, FTAG); 1117 } 1118 } 1119 } 1120 done: 1121 /* 1122 * Add this range to the dnode range list. 1123 * We will finish up this free operation in the syncing phase. 1124 */ 1125 mutex_enter(&dn->dn_mtx); 1126 dnode_clear_range(dn, blkid, nblks, tx); 1127 { 1128 free_range_t *rp, *found; 1129 avl_index_t where; 1130 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1131 1132 /* Add new range to dn_ranges */ 1133 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1134 rp->fr_blkid = blkid; 1135 rp->fr_nblks = nblks; 1136 found = avl_find(tree, rp, &where); 1137 ASSERT(found == NULL); 1138 avl_insert(tree, rp, where); 1139 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1140 blkid, nblks, tx->tx_txg); 1141 } 1142 mutex_exit(&dn->dn_mtx); 1143 1144 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1145 dnode_setdirty(dn, tx); 1146 out: 1147 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1148 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1149 1150 rw_exit(&dn->dn_struct_rwlock); 1151 } 1152 1153 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1154 uint64_t 1155 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1156 { 1157 free_range_t range_tofind; 1158 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1159 int i; 1160 1161 if (blkid == DB_BONUS_BLKID) 1162 return (FALSE); 1163 1164 /* 1165 * If we're in the process of opening the pool, dp will not be 1166 * set yet, but there shouldn't be anything dirty. 1167 */ 1168 if (dp == NULL) 1169 return (FALSE); 1170 1171 if (dn->dn_free_txg) 1172 return (TRUE); 1173 1174 range_tofind.fr_blkid = blkid; 1175 mutex_enter(&dn->dn_mtx); 1176 for (i = 0; i < TXG_SIZE; i++) { 1177 free_range_t *range_found; 1178 avl_index_t idx; 1179 1180 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1181 if (range_found) { 1182 ASSERT(range_found->fr_nblks > 0); 1183 break; 1184 } 1185 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1186 if (range_found && 1187 range_found->fr_blkid + range_found->fr_nblks > blkid) 1188 break; 1189 } 1190 mutex_exit(&dn->dn_mtx); 1191 return (i < TXG_SIZE); 1192 } 1193 1194 /* call from syncing context when we actually write/free space for this dnode */ 1195 void 1196 dnode_diduse_space(dnode_t *dn, int64_t delta) 1197 { 1198 uint64_t space; 1199 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1200 dn, dn->dn_phys, 1201 (u_longlong_t)dn->dn_phys->dn_used, 1202 (longlong_t)delta); 1203 1204 mutex_enter(&dn->dn_mtx); 1205 space = DN_USED_BYTES(dn->dn_phys); 1206 if (delta > 0) { 1207 ASSERT3U(space + delta, >=, space); /* no overflow */ 1208 } else { 1209 ASSERT3U(space, >=, -delta); /* no underflow */ 1210 } 1211 space += delta; 1212 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1213 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1214 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1215 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1216 } else { 1217 dn->dn_phys->dn_used = space; 1218 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1219 } 1220 mutex_exit(&dn->dn_mtx); 1221 } 1222 1223 /* 1224 * Call when we think we're going to write/free space in open context. 1225 * Be conservative (ie. OK to write less than this or free more than 1226 * this, but don't write more or free less). 1227 */ 1228 void 1229 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1230 { 1231 objset_impl_t *os = dn->dn_objset; 1232 dsl_dataset_t *ds = os->os_dsl_dataset; 1233 1234 if (space > 0) 1235 space = spa_get_asize(os->os_spa, space); 1236 1237 if (ds) 1238 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1239 1240 dmu_tx_willuse_space(tx, space); 1241 } 1242 1243 static int 1244 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1245 int lvl, uint64_t blkfill, uint64_t txg) 1246 { 1247 dmu_buf_impl_t *db = NULL; 1248 void *data = NULL; 1249 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1250 uint64_t epb = 1ULL << epbs; 1251 uint64_t minfill, maxfill; 1252 boolean_t hole; 1253 int i, inc, error, span; 1254 1255 dprintf("probing object %llu offset %llx level %d of %u\n", 1256 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1257 1258 hole = flags & DNODE_FIND_HOLE; 1259 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1260 ASSERT(txg == 0 || !hole); 1261 1262 if (lvl == dn->dn_phys->dn_nlevels) { 1263 error = 0; 1264 epb = dn->dn_phys->dn_nblkptr; 1265 data = dn->dn_phys->dn_blkptr; 1266 } else { 1267 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1268 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1269 if (error) { 1270 if (error != ENOENT) 1271 return (error); 1272 if (hole) 1273 return (0); 1274 /* 1275 * This can only happen when we are searching up 1276 * the block tree for data. We don't really need to 1277 * adjust the offset, as we will just end up looking 1278 * at the pointer to this block in its parent, and its 1279 * going to be unallocated, so we will skip over it. 1280 */ 1281 return (ESRCH); 1282 } 1283 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1284 if (error) { 1285 dbuf_rele(db, FTAG); 1286 return (error); 1287 } 1288 data = db->db.db_data; 1289 } 1290 1291 if (db && txg && 1292 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1293 /* 1294 * This can only happen when we are searching up the tree 1295 * and these conditions mean that we need to keep climbing. 1296 */ 1297 error = ESRCH; 1298 } else if (lvl == 0) { 1299 dnode_phys_t *dnp = data; 1300 span = DNODE_SHIFT; 1301 ASSERT(dn->dn_type == DMU_OT_DNODE); 1302 1303 for (i = (*offset >> span) & (blkfill - 1); 1304 i >= 0 && i < blkfill; i += inc) { 1305 boolean_t newcontents = B_TRUE; 1306 if (txg) { 1307 int j; 1308 newcontents = B_FALSE; 1309 for (j = 0; j < dnp[i].dn_nblkptr; j++) { 1310 if (dnp[i].dn_blkptr[j].blk_birth > txg) 1311 newcontents = B_TRUE; 1312 } 1313 } 1314 if (!dnp[i].dn_type == hole && newcontents) 1315 break; 1316 *offset += (1ULL << span) * inc; 1317 } 1318 if (i < 0 || i == blkfill) 1319 error = ESRCH; 1320 } else { 1321 blkptr_t *bp = data; 1322 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1323 minfill = 0; 1324 maxfill = blkfill << ((lvl - 1) * epbs); 1325 1326 if (hole) 1327 maxfill--; 1328 else 1329 minfill++; 1330 1331 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1332 i >= 0 && i < epb; i += inc) { 1333 if (bp[i].blk_fill >= minfill && 1334 bp[i].blk_fill <= maxfill && 1335 (hole || bp[i].blk_birth > txg)) 1336 break; 1337 if (inc < 0 && *offset < (1ULL << span)) 1338 *offset = 0; 1339 else 1340 *offset += (1ULL << span) * inc; 1341 } 1342 if (i < 0 || i == epb) 1343 error = ESRCH; 1344 } 1345 1346 if (db) 1347 dbuf_rele(db, FTAG); 1348 1349 return (error); 1350 } 1351 1352 /* 1353 * Find the next hole, data, or sparse region at or after *offset. 1354 * The value 'blkfill' tells us how many items we expect to find 1355 * in an L0 data block; this value is 1 for normal objects, 1356 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1357 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1358 * 1359 * Examples: 1360 * 1361 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1362 * Finds the next/previous hole/data in a file. 1363 * Used in dmu_offset_next(). 1364 * 1365 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1366 * Finds the next free/allocated dnode an objset's meta-dnode. 1367 * Only finds objects that have new contents since txg (ie. 1368 * bonus buffer changes and content removal are ignored). 1369 * Used in dmu_object_next(). 1370 * 1371 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1372 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1373 * Used in dmu_object_alloc(). 1374 */ 1375 int 1376 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1377 int minlvl, uint64_t blkfill, uint64_t txg) 1378 { 1379 uint64_t initial_offset = *offset; 1380 int lvl, maxlvl; 1381 int error = 0; 1382 1383 if (!(flags & DNODE_FIND_HAVELOCK)) 1384 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1385 1386 if (dn->dn_phys->dn_nlevels == 0) { 1387 error = ESRCH; 1388 goto out; 1389 } 1390 1391 if (dn->dn_datablkshift == 0) { 1392 if (*offset < dn->dn_datablksz) { 1393 if (flags & DNODE_FIND_HOLE) 1394 *offset = dn->dn_datablksz; 1395 } else { 1396 error = ESRCH; 1397 } 1398 goto out; 1399 } 1400 1401 maxlvl = dn->dn_phys->dn_nlevels; 1402 1403 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1404 error = dnode_next_offset_level(dn, 1405 flags, offset, lvl, blkfill, txg); 1406 if (error != ESRCH) 1407 break; 1408 } 1409 1410 while (error == 0 && --lvl >= minlvl) { 1411 error = dnode_next_offset_level(dn, 1412 flags, offset, lvl, blkfill, txg); 1413 } 1414 1415 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1416 initial_offset < *offset : initial_offset > *offset)) 1417 error = ESRCH; 1418 out: 1419 if (!(flags & DNODE_FIND_HAVELOCK)) 1420 rw_exit(&dn->dn_struct_rwlock); 1421 1422 return (error); 1423 } 1424