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 i, nblkptr; 421 dmu_buf_impl_t *db = NULL; 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 for (i = 0; i < TXG_SIZE; i++) 434 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 435 436 /* clean up any unreferenced dbufs */ 437 dnode_evict_dbufs(dn); 438 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 439 440 /* 441 * XXX I should really have a generation number to tell if we 442 * need to do this... 443 */ 444 if (blocksize != dn->dn_datablksz || 445 dn->dn_bonustype != bonustype || dn->dn_bonuslen != bonuslen) { 446 /* free all old data */ 447 dnode_free_range(dn, 0, -1ULL, tx); 448 } 449 450 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 451 452 /* change blocksize */ 453 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 454 if (blocksize != dn->dn_datablksz && 455 (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 456 list_head(&dn->dn_dbufs) != NULL)) { 457 db = dbuf_hold(dn, 0, FTAG); 458 dbuf_new_size(db, blocksize, tx); 459 } 460 dnode_setdblksz(dn, blocksize); 461 dnode_setdirty(dn, tx); 462 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 463 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 464 if (dn->dn_nblkptr != nblkptr) 465 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 466 rw_exit(&dn->dn_struct_rwlock); 467 if (db) 468 dbuf_rele(db, FTAG); 469 470 /* change type */ 471 dn->dn_type = ot; 472 473 /* change bonus size and type */ 474 mutex_enter(&dn->dn_mtx); 475 dn->dn_bonustype = bonustype; 476 dn->dn_bonuslen = bonuslen; 477 dn->dn_nblkptr = nblkptr; 478 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 479 dn->dn_compress = ZIO_COMPRESS_INHERIT; 480 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 481 482 /* fix up the bonus db_size */ 483 if (dn->dn_bonus) { 484 dn->dn_bonus->db.db_size = 485 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 486 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 487 } 488 489 dn->dn_allocated_txg = tx->tx_txg; 490 mutex_exit(&dn->dn_mtx); 491 } 492 493 void 494 dnode_special_close(dnode_t *dn) 495 { 496 /* 497 * Wait for final references to the dnode to clear. This can 498 * only happen if the arc is asyncronously evicting state that 499 * has a hold on this dnode while we are trying to evict this 500 * dnode. 501 */ 502 while (refcount_count(&dn->dn_holds) > 0) 503 delay(1); 504 dnode_destroy(dn); 505 } 506 507 dnode_t * 508 dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 509 { 510 dnode_t *dn = dnode_create(os, dnp, NULL, object); 511 DNODE_VERIFY(dn); 512 return (dn); 513 } 514 515 static void 516 dnode_buf_pageout(dmu_buf_t *db, void *arg) 517 { 518 dnode_t **children_dnodes = arg; 519 int i; 520 int epb = db->db_size >> DNODE_SHIFT; 521 522 for (i = 0; i < epb; i++) { 523 dnode_t *dn = children_dnodes[i]; 524 int n; 525 526 if (dn == NULL) 527 continue; 528 #ifdef ZFS_DEBUG 529 /* 530 * If there are holds on this dnode, then there should 531 * be holds on the dnode's containing dbuf as well; thus 532 * it wouldn't be eligable for eviction and this function 533 * would not have been called. 534 */ 535 ASSERT(refcount_is_zero(&dn->dn_holds)); 536 ASSERT(list_head(&dn->dn_dbufs) == NULL); 537 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 538 539 for (n = 0; n < TXG_SIZE; n++) 540 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 541 #endif 542 children_dnodes[i] = NULL; 543 dnode_destroy(dn); 544 } 545 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 546 } 547 548 /* 549 * errors: 550 * EINVAL - invalid object number. 551 * EIO - i/o error. 552 * succeeds even for free dnodes. 553 */ 554 int 555 dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 556 void *tag, dnode_t **dnp) 557 { 558 int epb, idx, err; 559 int drop_struct_lock = FALSE; 560 int type; 561 uint64_t blk; 562 dnode_t *mdn, *dn; 563 dmu_buf_impl_t *db; 564 dnode_t **children_dnodes; 565 566 /* 567 * If you are holding the spa config lock as writer, you shouldn't 568 * be asking the DMU to do *anything*. 569 */ 570 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0); 571 572 if (object == 0 || object >= DN_MAX_OBJECT) 573 return (EINVAL); 574 575 mdn = os->os_meta_dnode; 576 577 DNODE_VERIFY(mdn); 578 579 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 580 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 581 drop_struct_lock = TRUE; 582 } 583 584 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 585 586 db = dbuf_hold(mdn, blk, FTAG); 587 if (drop_struct_lock) 588 rw_exit(&mdn->dn_struct_rwlock); 589 if (db == NULL) 590 return (EIO); 591 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 592 if (err) { 593 dbuf_rele(db, FTAG); 594 return (err); 595 } 596 597 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 598 epb = db->db.db_size >> DNODE_SHIFT; 599 600 idx = object & (epb-1); 601 602 children_dnodes = dmu_buf_get_user(&db->db); 603 if (children_dnodes == NULL) { 604 dnode_t **winner; 605 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 606 KM_SLEEP); 607 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 608 dnode_buf_pageout)) { 609 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 610 children_dnodes = winner; 611 } 612 } 613 614 if ((dn = children_dnodes[idx]) == NULL) { 615 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 616 dnode_t *winner; 617 618 dn = dnode_create(os, dnp, db, object); 619 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 620 if (winner != NULL) { 621 dnode_destroy(dn); 622 dn = winner; 623 } 624 } 625 626 mutex_enter(&dn->dn_mtx); 627 type = dn->dn_type; 628 if (dn->dn_free_txg || 629 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 630 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 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_impl_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_impl_t *os = dn->dn_objset; 693 uint64_t txg = tx->tx_txg; 694 695 if (dn->dn_object == DMU_META_DNODE_OBJECT) 696 return; 697 698 DNODE_VERIFY(dn); 699 700 #ifdef ZFS_DEBUG 701 mutex_enter(&dn->dn_mtx); 702 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 703 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 704 mutex_exit(&dn->dn_mtx); 705 #endif 706 707 mutex_enter(&os->os_lock); 708 709 /* 710 * If we are already marked dirty, we're done. 711 */ 712 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 713 mutex_exit(&os->os_lock); 714 return; 715 } 716 717 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 718 ASSERT(dn->dn_datablksz != 0); 719 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 720 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 721 722 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 723 dn->dn_object, txg); 724 725 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 726 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 727 } else { 728 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 729 } 730 731 mutex_exit(&os->os_lock); 732 733 /* 734 * The dnode maintains a hold on its containing dbuf as 735 * long as there are holds on it. Each instantiated child 736 * dbuf maintaines a hold on the dnode. When the last child 737 * drops its hold, the dnode will drop its hold on the 738 * containing dbuf. We add a "dirty hold" here so that the 739 * dnode will hang around after we finish processing its 740 * children. 741 */ 742 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 743 744 (void) dbuf_dirty(dn->dn_dbuf, tx); 745 746 dsl_dataset_dirty(os->os_dsl_dataset, tx); 747 } 748 749 void 750 dnode_free(dnode_t *dn, dmu_tx_t *tx) 751 { 752 int txgoff = tx->tx_txg & TXG_MASK; 753 754 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 755 756 /* we should be the only holder... hopefully */ 757 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 758 759 mutex_enter(&dn->dn_mtx); 760 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 761 mutex_exit(&dn->dn_mtx); 762 return; 763 } 764 dn->dn_free_txg = tx->tx_txg; 765 mutex_exit(&dn->dn_mtx); 766 767 /* 768 * If the dnode is already dirty, it needs to be moved from 769 * the dirty list to the free list. 770 */ 771 mutex_enter(&dn->dn_objset->os_lock); 772 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 773 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 774 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 775 mutex_exit(&dn->dn_objset->os_lock); 776 } else { 777 mutex_exit(&dn->dn_objset->os_lock); 778 dnode_setdirty(dn, tx); 779 } 780 } 781 782 /* 783 * Try to change the block size for the indicated dnode. This can only 784 * succeed if there are no blocks allocated or dirty beyond first block 785 */ 786 int 787 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 788 { 789 dmu_buf_impl_t *db, *db_next; 790 int err; 791 792 if (size == 0) 793 size = SPA_MINBLOCKSIZE; 794 if (size > SPA_MAXBLOCKSIZE) 795 size = SPA_MAXBLOCKSIZE; 796 else 797 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 798 799 if (ibs == dn->dn_indblkshift) 800 ibs = 0; 801 802 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 803 return (0); 804 805 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 806 807 /* Check for any allocated blocks beyond the first */ 808 if (dn->dn_phys->dn_maxblkid != 0) 809 goto fail; 810 811 mutex_enter(&dn->dn_dbufs_mtx); 812 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 813 db_next = list_next(&dn->dn_dbufs, db); 814 815 if (db->db_blkid != 0 && db->db_blkid != DB_BONUS_BLKID) { 816 mutex_exit(&dn->dn_dbufs_mtx); 817 goto fail; 818 } 819 } 820 mutex_exit(&dn->dn_dbufs_mtx); 821 822 if (ibs && dn->dn_nlevels != 1) 823 goto fail; 824 825 /* resize the old block */ 826 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 827 if (err == 0) 828 dbuf_new_size(db, size, tx); 829 else if (err != ENOENT) 830 goto fail; 831 832 dnode_setdblksz(dn, size); 833 dnode_setdirty(dn, tx); 834 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 835 if (ibs) { 836 dn->dn_indblkshift = ibs; 837 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 838 } 839 /* rele after we have fixed the blocksize in the dnode */ 840 if (db) 841 dbuf_rele(db, FTAG); 842 843 rw_exit(&dn->dn_struct_rwlock); 844 return (0); 845 846 fail: 847 rw_exit(&dn->dn_struct_rwlock); 848 return (ENOTSUP); 849 } 850 851 /* read-holding callers must not rely on the lock being continuously held */ 852 void 853 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 854 { 855 uint64_t txgoff = tx->tx_txg & TXG_MASK; 856 int epbs, new_nlevels; 857 uint64_t sz; 858 859 ASSERT(blkid != DB_BONUS_BLKID); 860 861 ASSERT(have_read ? 862 RW_READ_HELD(&dn->dn_struct_rwlock) : 863 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 864 865 /* 866 * if we have a read-lock, check to see if we need to do any work 867 * before upgrading to a write-lock. 868 */ 869 if (have_read) { 870 if (blkid <= dn->dn_maxblkid) 871 return; 872 873 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 874 rw_exit(&dn->dn_struct_rwlock); 875 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 876 } 877 } 878 879 if (blkid <= dn->dn_maxblkid) 880 goto out; 881 882 dn->dn_maxblkid = blkid; 883 884 /* 885 * Compute the number of levels necessary to support the new maxblkid. 886 */ 887 new_nlevels = 1; 888 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 889 for (sz = dn->dn_nblkptr; 890 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 891 new_nlevels++; 892 893 if (new_nlevels > dn->dn_nlevels) { 894 int old_nlevels = dn->dn_nlevels; 895 dmu_buf_impl_t *db; 896 list_t *list; 897 dbuf_dirty_record_t *new, *dr, *dr_next; 898 899 dn->dn_nlevels = new_nlevels; 900 901 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 902 dn->dn_next_nlevels[txgoff] = new_nlevels; 903 904 /* dirty the left indirects */ 905 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 906 new = dbuf_dirty(db, tx); 907 dbuf_rele(db, FTAG); 908 909 /* transfer the dirty records to the new indirect */ 910 mutex_enter(&dn->dn_mtx); 911 mutex_enter(&new->dt.di.dr_mtx); 912 list = &dn->dn_dirty_records[txgoff]; 913 for (dr = list_head(list); dr; dr = dr_next) { 914 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 915 if (dr->dr_dbuf->db_level != new_nlevels-1 && 916 dr->dr_dbuf->db_blkid != DB_BONUS_BLKID) { 917 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 918 list_remove(&dn->dn_dirty_records[txgoff], dr); 919 list_insert_tail(&new->dt.di.dr_children, dr); 920 dr->dr_parent = new; 921 } 922 } 923 mutex_exit(&new->dt.di.dr_mtx); 924 mutex_exit(&dn->dn_mtx); 925 } 926 927 out: 928 if (have_read) 929 rw_downgrade(&dn->dn_struct_rwlock); 930 } 931 932 void 933 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 934 { 935 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 936 avl_index_t where; 937 free_range_t *rp; 938 free_range_t rp_tofind; 939 uint64_t endblk = blkid + nblks; 940 941 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 942 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 943 944 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 945 blkid, nblks, tx->tx_txg); 946 rp_tofind.fr_blkid = blkid; 947 rp = avl_find(tree, &rp_tofind, &where); 948 if (rp == NULL) 949 rp = avl_nearest(tree, where, AVL_BEFORE); 950 if (rp == NULL) 951 rp = avl_nearest(tree, where, AVL_AFTER); 952 953 while (rp && (rp->fr_blkid <= blkid + nblks)) { 954 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 955 free_range_t *nrp = AVL_NEXT(tree, rp); 956 957 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 958 /* clear this entire range */ 959 avl_remove(tree, rp); 960 kmem_free(rp, sizeof (free_range_t)); 961 } else if (blkid <= rp->fr_blkid && 962 endblk > rp->fr_blkid && endblk < fr_endblk) { 963 /* clear the beginning of this range */ 964 rp->fr_blkid = endblk; 965 rp->fr_nblks = fr_endblk - endblk; 966 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 967 endblk >= fr_endblk) { 968 /* clear the end of this range */ 969 rp->fr_nblks = blkid - rp->fr_blkid; 970 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 971 /* clear a chunk out of this range */ 972 free_range_t *new_rp = 973 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 974 975 new_rp->fr_blkid = endblk; 976 new_rp->fr_nblks = fr_endblk - endblk; 977 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 978 rp->fr_nblks = blkid - rp->fr_blkid; 979 } 980 /* there may be no overlap */ 981 rp = nrp; 982 } 983 } 984 985 void 986 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 987 { 988 dmu_buf_impl_t *db; 989 uint64_t blkoff, blkid, nblks; 990 int blksz, blkshift, head, tail; 991 int trunc = FALSE; 992 int epbs; 993 994 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 995 blksz = dn->dn_datablksz; 996 blkshift = dn->dn_datablkshift; 997 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 998 999 if (len == -1ULL) { 1000 len = UINT64_MAX - off; 1001 trunc = TRUE; 1002 } 1003 1004 /* 1005 * First, block align the region to free: 1006 */ 1007 if (ISP2(blksz)) { 1008 head = P2NPHASE(off, blksz); 1009 blkoff = P2PHASE(off, blksz); 1010 if ((off >> blkshift) > dn->dn_maxblkid) 1011 goto out; 1012 } else { 1013 ASSERT(dn->dn_maxblkid == 0); 1014 if (off == 0 && len >= blksz) { 1015 /* Freeing the whole block; fast-track this request */ 1016 blkid = 0; 1017 nblks = 1; 1018 goto done; 1019 } else if (off >= blksz) { 1020 /* Freeing past end-of-data */ 1021 goto out; 1022 } else { 1023 /* Freeing part of the block. */ 1024 head = blksz - off; 1025 ASSERT3U(head, >, 0); 1026 } 1027 blkoff = off; 1028 } 1029 /* zero out any partial block data at the start of the range */ 1030 if (head) { 1031 ASSERT3U(blkoff + head, ==, blksz); 1032 if (len < head) 1033 head = len; 1034 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1035 FTAG, &db) == 0) { 1036 caddr_t data; 1037 1038 /* don't dirty if it isn't on disk and isn't dirty */ 1039 if (db->db_last_dirty || 1040 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1041 rw_exit(&dn->dn_struct_rwlock); 1042 dbuf_will_dirty(db, tx); 1043 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1044 data = db->db.db_data; 1045 bzero(data + blkoff, head); 1046 } 1047 dbuf_rele(db, FTAG); 1048 } 1049 off += head; 1050 len -= head; 1051 } 1052 1053 /* If the range was less than one block, we're done */ 1054 if (len == 0) 1055 goto out; 1056 1057 /* If the remaining range is past end of file, we're done */ 1058 if ((off >> blkshift) > dn->dn_maxblkid) 1059 goto out; 1060 1061 ASSERT(ISP2(blksz)); 1062 if (trunc) 1063 tail = 0; 1064 else 1065 tail = P2PHASE(len, blksz); 1066 1067 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1068 /* zero out any partial block data at the end of the range */ 1069 if (tail) { 1070 if (len < tail) 1071 tail = len; 1072 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1073 TRUE, FTAG, &db) == 0) { 1074 /* don't dirty if not on disk and not dirty */ 1075 if (db->db_last_dirty || 1076 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1077 rw_exit(&dn->dn_struct_rwlock); 1078 dbuf_will_dirty(db, tx); 1079 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1080 bzero(db->db.db_data, tail); 1081 } 1082 dbuf_rele(db, FTAG); 1083 } 1084 len -= tail; 1085 } 1086 1087 /* If the range did not include a full block, we are done */ 1088 if (len == 0) 1089 goto out; 1090 1091 ASSERT(IS_P2ALIGNED(off, blksz)); 1092 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1093 blkid = off >> blkshift; 1094 nblks = len >> blkshift; 1095 if (trunc) 1096 nblks += 1; 1097 1098 /* 1099 * Read in and mark all the level-1 indirects dirty, 1100 * so that they will stay in memory until syncing phase. 1101 * Always dirty the first and last indirect to make sure 1102 * we dirty all the partial indirects. 1103 */ 1104 if (dn->dn_nlevels > 1) { 1105 uint64_t i, first, last; 1106 int shift = epbs + dn->dn_datablkshift; 1107 1108 first = blkid >> epbs; 1109 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1110 dbuf_will_dirty(db, tx); 1111 dbuf_rele(db, FTAG); 1112 } 1113 if (trunc) 1114 last = dn->dn_maxblkid >> epbs; 1115 else 1116 last = (blkid + nblks - 1) >> epbs; 1117 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1118 dbuf_will_dirty(db, tx); 1119 dbuf_rele(db, FTAG); 1120 } 1121 for (i = first + 1; i < last; i++) { 1122 uint64_t ibyte = i << shift; 1123 int err; 1124 1125 err = dnode_next_offset(dn, 1126 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1127 i = ibyte >> shift; 1128 if (err == ESRCH || i >= last) 1129 break; 1130 ASSERT(err == 0); 1131 db = dbuf_hold_level(dn, 1, i, FTAG); 1132 if (db) { 1133 dbuf_will_dirty(db, tx); 1134 dbuf_rele(db, FTAG); 1135 } 1136 } 1137 } 1138 done: 1139 /* 1140 * Add this range to the dnode range list. 1141 * We will finish up this free operation in the syncing phase. 1142 */ 1143 mutex_enter(&dn->dn_mtx); 1144 dnode_clear_range(dn, blkid, nblks, tx); 1145 { 1146 free_range_t *rp, *found; 1147 avl_index_t where; 1148 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1149 1150 /* Add new range to dn_ranges */ 1151 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1152 rp->fr_blkid = blkid; 1153 rp->fr_nblks = nblks; 1154 found = avl_find(tree, rp, &where); 1155 ASSERT(found == NULL); 1156 avl_insert(tree, rp, where); 1157 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1158 blkid, nblks, tx->tx_txg); 1159 } 1160 mutex_exit(&dn->dn_mtx); 1161 1162 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1163 dnode_setdirty(dn, tx); 1164 out: 1165 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1166 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1167 1168 rw_exit(&dn->dn_struct_rwlock); 1169 } 1170 1171 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1172 uint64_t 1173 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1174 { 1175 free_range_t range_tofind; 1176 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1177 int i; 1178 1179 if (blkid == DB_BONUS_BLKID) 1180 return (FALSE); 1181 1182 /* 1183 * If we're in the process of opening the pool, dp will not be 1184 * set yet, but there shouldn't be anything dirty. 1185 */ 1186 if (dp == NULL) 1187 return (FALSE); 1188 1189 if (dn->dn_free_txg) 1190 return (TRUE); 1191 1192 /* 1193 * If dn_datablkshift is not set, then there's only a single 1194 * block, in which case there will never be a free range so it 1195 * won't matter. 1196 */ 1197 range_tofind.fr_blkid = blkid; 1198 mutex_enter(&dn->dn_mtx); 1199 for (i = 0; i < TXG_SIZE; i++) { 1200 free_range_t *range_found; 1201 avl_index_t idx; 1202 1203 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1204 if (range_found) { 1205 ASSERT(range_found->fr_nblks > 0); 1206 break; 1207 } 1208 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1209 if (range_found && 1210 range_found->fr_blkid + range_found->fr_nblks > blkid) 1211 break; 1212 } 1213 mutex_exit(&dn->dn_mtx); 1214 return (i < TXG_SIZE); 1215 } 1216 1217 /* call from syncing context when we actually write/free space for this dnode */ 1218 void 1219 dnode_diduse_space(dnode_t *dn, int64_t delta) 1220 { 1221 uint64_t space; 1222 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1223 dn, dn->dn_phys, 1224 (u_longlong_t)dn->dn_phys->dn_used, 1225 (longlong_t)delta); 1226 1227 mutex_enter(&dn->dn_mtx); 1228 space = DN_USED_BYTES(dn->dn_phys); 1229 if (delta > 0) { 1230 ASSERT3U(space + delta, >=, space); /* no overflow */ 1231 } else { 1232 ASSERT3U(space, >=, -delta); /* no underflow */ 1233 } 1234 space += delta; 1235 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1236 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1237 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1238 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1239 } else { 1240 dn->dn_phys->dn_used = space; 1241 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1242 } 1243 mutex_exit(&dn->dn_mtx); 1244 } 1245 1246 /* 1247 * Call when we think we're going to write/free space in open context. 1248 * Be conservative (ie. OK to write less than this or free more than 1249 * this, but don't write more or free less). 1250 */ 1251 void 1252 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1253 { 1254 objset_impl_t *os = dn->dn_objset; 1255 dsl_dataset_t *ds = os->os_dsl_dataset; 1256 1257 if (space > 0) 1258 space = spa_get_asize(os->os_spa, space); 1259 1260 if (ds) 1261 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1262 1263 dmu_tx_willuse_space(tx, space); 1264 } 1265 1266 static int 1267 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1268 int lvl, uint64_t blkfill, uint64_t txg) 1269 { 1270 dmu_buf_impl_t *db = NULL; 1271 void *data = NULL; 1272 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1273 uint64_t epb = 1ULL << epbs; 1274 uint64_t minfill, maxfill; 1275 boolean_t hole; 1276 int i, inc, error, span; 1277 1278 dprintf("probing object %llu offset %llx level %d of %u\n", 1279 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1280 1281 hole = flags & DNODE_FIND_HOLE; 1282 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1283 ASSERT(txg == 0 || !hole); 1284 1285 if (lvl == dn->dn_phys->dn_nlevels) { 1286 error = 0; 1287 epb = dn->dn_phys->dn_nblkptr; 1288 data = dn->dn_phys->dn_blkptr; 1289 } else { 1290 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1291 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1292 if (error) { 1293 if (error != ENOENT) 1294 return (error); 1295 if (hole) 1296 return (0); 1297 /* 1298 * This can only happen when we are searching up 1299 * the block tree for data. We don't really need to 1300 * adjust the offset, as we will just end up looking 1301 * at the pointer to this block in its parent, and its 1302 * going to be unallocated, so we will skip over it. 1303 */ 1304 return (ESRCH); 1305 } 1306 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1307 if (error) { 1308 dbuf_rele(db, FTAG); 1309 return (error); 1310 } 1311 data = db->db.db_data; 1312 } 1313 1314 if (db && txg && 1315 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1316 /* 1317 * This can only happen when we are searching up the tree 1318 * and these conditions mean that we need to keep climbing. 1319 */ 1320 error = ESRCH; 1321 } else if (lvl == 0) { 1322 dnode_phys_t *dnp = data; 1323 span = DNODE_SHIFT; 1324 ASSERT(dn->dn_type == DMU_OT_DNODE); 1325 1326 for (i = (*offset >> span) & (blkfill - 1); 1327 i >= 0 && i < blkfill; i += inc) { 1328 boolean_t newcontents = B_TRUE; 1329 if (txg) { 1330 int j; 1331 newcontents = B_FALSE; 1332 for (j = 0; j < dnp[i].dn_nblkptr; j++) { 1333 if (dnp[i].dn_blkptr[j].blk_birth > txg) 1334 newcontents = B_TRUE; 1335 } 1336 } 1337 if (!dnp[i].dn_type == hole && newcontents) 1338 break; 1339 *offset += (1ULL << span) * inc; 1340 } 1341 if (i < 0 || i == blkfill) 1342 error = ESRCH; 1343 } else { 1344 blkptr_t *bp = data; 1345 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1346 minfill = 0; 1347 maxfill = blkfill << ((lvl - 1) * epbs); 1348 1349 if (hole) 1350 maxfill--; 1351 else 1352 minfill++; 1353 1354 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1355 i >= 0 && i < epb; i += inc) { 1356 if (bp[i].blk_fill >= minfill && 1357 bp[i].blk_fill <= maxfill && 1358 (hole || bp[i].blk_birth > txg)) 1359 break; 1360 if (inc < 0 && *offset < (1ULL << span)) 1361 *offset = 0; 1362 else 1363 *offset += (1ULL << span) * inc; 1364 } 1365 if (i < 0 || i == epb) 1366 error = ESRCH; 1367 } 1368 1369 if (db) 1370 dbuf_rele(db, FTAG); 1371 1372 return (error); 1373 } 1374 1375 /* 1376 * Find the next hole, data, or sparse region at or after *offset. 1377 * The value 'blkfill' tells us how many items we expect to find 1378 * in an L0 data block; this value is 1 for normal objects, 1379 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1380 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1381 * 1382 * Examples: 1383 * 1384 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1385 * Finds the next/previous hole/data in a file. 1386 * Used in dmu_offset_next(). 1387 * 1388 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1389 * Finds the next free/allocated dnode an objset's meta-dnode. 1390 * Only finds objects that have new contents since txg (ie. 1391 * bonus buffer changes and content removal are ignored). 1392 * Used in dmu_object_next(). 1393 * 1394 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1395 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1396 * Used in dmu_object_alloc(). 1397 */ 1398 int 1399 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1400 int minlvl, uint64_t blkfill, uint64_t txg) 1401 { 1402 uint64_t initial_offset = *offset; 1403 int lvl, maxlvl; 1404 int error = 0; 1405 1406 if (!(flags & DNODE_FIND_HAVELOCK)) 1407 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1408 1409 if (dn->dn_phys->dn_nlevels == 0) { 1410 error = ESRCH; 1411 goto out; 1412 } 1413 1414 if (dn->dn_datablkshift == 0) { 1415 if (*offset < dn->dn_datablksz) { 1416 if (flags & DNODE_FIND_HOLE) 1417 *offset = dn->dn_datablksz; 1418 } else { 1419 error = ESRCH; 1420 } 1421 goto out; 1422 } 1423 1424 maxlvl = dn->dn_phys->dn_nlevels; 1425 1426 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1427 error = dnode_next_offset_level(dn, 1428 flags, offset, lvl, blkfill, txg); 1429 if (error != ESRCH) 1430 break; 1431 } 1432 1433 while (error == 0 && --lvl >= minlvl) { 1434 error = dnode_next_offset_level(dn, 1435 flags, offset, lvl, blkfill, txg); 1436 } 1437 1438 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1439 initial_offset < *offset : initial_offset > *offset)) 1440 error = ESRCH; 1441 out: 1442 if (!(flags & DNODE_FIND_HAVELOCK)) 1443 rw_exit(&dn->dn_struct_rwlock); 1444 1445 return (error); 1446 } 1447