1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "@(#)dnode.c 1.20 07/08/26 SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/dbuf.h> 30 #include <sys/dnode.h> 31 #include <sys/dmu.h> 32 #include <sys/dmu_impl.h> 33 #include <sys/dmu_tx.h> 34 #include <sys/dmu_objset.h> 35 #include <sys/dsl_dir.h> 36 #include <sys/dsl_dataset.h> 37 #include <sys/spa.h> 38 #include <sys/zio.h> 39 #include <sys/dmu_zfetch.h> 40 41 static int free_range_compar(const void *node1, const void *node2); 42 43 static kmem_cache_t *dnode_cache; 44 45 static dnode_phys_t dnode_phys_zero; 46 47 int zfs_default_bs = SPA_MINBLOCKSHIFT; 48 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 49 50 /* ARGSUSED */ 51 static int 52 dnode_cons(void *arg, void *unused, int kmflag) 53 { 54 int i; 55 dnode_t *dn = arg; 56 bzero(dn, sizeof (dnode_t)); 57 58 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 59 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 60 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 61 refcount_create(&dn->dn_holds); 62 refcount_create(&dn->dn_tx_holds); 63 64 for (i = 0; i < TXG_SIZE; i++) { 65 avl_create(&dn->dn_ranges[i], free_range_compar, 66 sizeof (free_range_t), 67 offsetof(struct free_range, fr_node)); 68 list_create(&dn->dn_dirty_records[i], 69 sizeof (dbuf_dirty_record_t), 70 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 71 } 72 73 list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), 74 offsetof(dmu_buf_impl_t, db_link)); 75 76 return (0); 77 } 78 79 /* ARGSUSED */ 80 static void 81 dnode_dest(void *arg, void *unused) 82 { 83 int i; 84 dnode_t *dn = arg; 85 86 rw_destroy(&dn->dn_struct_rwlock); 87 mutex_destroy(&dn->dn_mtx); 88 mutex_destroy(&dn->dn_dbufs_mtx); 89 refcount_destroy(&dn->dn_holds); 90 refcount_destroy(&dn->dn_tx_holds); 91 92 for (i = 0; i < TXG_SIZE; i++) { 93 avl_destroy(&dn->dn_ranges[i]); 94 list_destroy(&dn->dn_dirty_records[i]); 95 } 96 97 list_destroy(&dn->dn_dbufs); 98 } 99 100 void 101 dnode_init(void) 102 { 103 dnode_cache = kmem_cache_create("dnode_t", 104 sizeof (dnode_t), 105 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 106 } 107 108 void 109 dnode_fini(void) 110 { 111 kmem_cache_destroy(dnode_cache); 112 } 113 114 115 #ifdef ZFS_DEBUG 116 void 117 dnode_verify(dnode_t *dn) 118 { 119 int drop_struct_lock = FALSE; 120 121 ASSERT(dn->dn_phys); 122 ASSERT(dn->dn_objset); 123 124 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 125 126 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 127 return; 128 129 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 130 rw_enter(&dn->dn_struct_rwlock, RW_READER); 131 drop_struct_lock = TRUE; 132 } 133 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 134 int i; 135 ASSERT3U(dn->dn_indblkshift, >=, 0); 136 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 137 if (dn->dn_datablkshift) { 138 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 139 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 140 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 141 } 142 ASSERT3U(dn->dn_nlevels, <=, 30); 143 ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); 144 ASSERT3U(dn->dn_nblkptr, >=, 1); 145 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 146 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 147 ASSERT3U(dn->dn_datablksz, ==, 148 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 149 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 150 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 151 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 152 for (i = 0; i < TXG_SIZE; i++) { 153 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 154 } 155 } 156 if (dn->dn_phys->dn_type != DMU_OT_NONE) 157 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 158 ASSERT(dn->dn_object == DMU_META_DNODE_OBJECT || dn->dn_dbuf != NULL); 159 if (dn->dn_dbuf != NULL) { 160 ASSERT3P(dn->dn_phys, ==, 161 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 162 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 163 } 164 if (drop_struct_lock) 165 rw_exit(&dn->dn_struct_rwlock); 166 } 167 #endif 168 169 void 170 dnode_byteswap(dnode_phys_t *dnp) 171 { 172 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 173 int i; 174 175 if (dnp->dn_type == DMU_OT_NONE) { 176 bzero(dnp, sizeof (dnode_phys_t)); 177 return; 178 } 179 180 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 181 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 182 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 183 dnp->dn_used = BSWAP_64(dnp->dn_used); 184 185 /* 186 * dn_nblkptr is only one byte, so it's OK to read it in either 187 * byte order. We can't read dn_bouslen. 188 */ 189 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 190 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 191 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 192 buf64[i] = BSWAP_64(buf64[i]); 193 194 /* 195 * OK to check dn_bonuslen for zero, because it won't matter if 196 * we have the wrong byte order. This is necessary because the 197 * dnode dnode is smaller than a regular dnode. 198 */ 199 if (dnp->dn_bonuslen != 0) { 200 /* 201 * Note that the bonus length calculated here may be 202 * longer than the actual bonus buffer. This is because 203 * we always put the bonus buffer after the last block 204 * pointer (instead of packing it against the end of the 205 * dnode buffer). 206 */ 207 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 208 size_t len = DN_MAX_BONUSLEN - off; 209 ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); 210 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 211 } 212 } 213 214 void 215 dnode_buf_byteswap(void *vbuf, size_t size) 216 { 217 dnode_phys_t *buf = vbuf; 218 int i; 219 220 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 221 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 222 223 size >>= DNODE_SHIFT; 224 for (i = 0; i < size; i++) { 225 dnode_byteswap(buf); 226 buf++; 227 } 228 } 229 230 static int 231 free_range_compar(const void *node1, const void *node2) 232 { 233 const free_range_t *rp1 = node1; 234 const free_range_t *rp2 = node2; 235 236 if (rp1->fr_blkid < rp2->fr_blkid) 237 return (-1); 238 else if (rp1->fr_blkid > rp2->fr_blkid) 239 return (1); 240 else return (0); 241 } 242 243 void 244 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 245 { 246 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 247 248 dnode_setdirty(dn, tx); 249 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 250 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 251 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 252 dn->dn_bonuslen = newsize; 253 if (newsize == 0) 254 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 255 else 256 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 257 rw_exit(&dn->dn_struct_rwlock); 258 } 259 260 static void 261 dnode_setdblksz(dnode_t *dn, int size) 262 { 263 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 264 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 265 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 266 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 267 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 268 dn->dn_datablksz = size; 269 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 270 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 271 } 272 273 static dnode_t * 274 dnode_create(objset_impl_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 275 uint64_t object) 276 { 277 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 278 (void) dnode_cons(dn, NULL, 0); /* XXX */ 279 280 dn->dn_objset = os; 281 dn->dn_object = object; 282 dn->dn_dbuf = db; 283 dn->dn_phys = dnp; 284 285 if (dnp->dn_datablkszsec) 286 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 287 dn->dn_indblkshift = dnp->dn_indblkshift; 288 dn->dn_nlevels = dnp->dn_nlevels; 289 dn->dn_type = dnp->dn_type; 290 dn->dn_nblkptr = dnp->dn_nblkptr; 291 dn->dn_checksum = dnp->dn_checksum; 292 dn->dn_compress = dnp->dn_compress; 293 dn->dn_bonustype = dnp->dn_bonustype; 294 dn->dn_bonuslen = dnp->dn_bonuslen; 295 dn->dn_maxblkid = dnp->dn_maxblkid; 296 297 dmu_zfetch_init(&dn->dn_zfetch, dn); 298 299 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 300 mutex_enter(&os->os_lock); 301 list_insert_head(&os->os_dnodes, dn); 302 mutex_exit(&os->os_lock); 303 304 arc_space_consume(sizeof (dnode_t)); 305 return (dn); 306 } 307 308 static void 309 dnode_destroy(dnode_t *dn) 310 { 311 objset_impl_t *os = dn->dn_objset; 312 313 #ifdef ZFS_DEBUG 314 int i; 315 316 for (i = 0; i < TXG_SIZE; i++) { 317 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 318 ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); 319 ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); 320 } 321 ASSERT(NULL == list_head(&dn->dn_dbufs)); 322 #endif 323 324 mutex_enter(&os->os_lock); 325 list_remove(&os->os_dnodes, dn); 326 mutex_exit(&os->os_lock); 327 328 if (dn->dn_dirtyctx_firstset) { 329 kmem_free(dn->dn_dirtyctx_firstset, 1); 330 dn->dn_dirtyctx_firstset = NULL; 331 } 332 dmu_zfetch_rele(&dn->dn_zfetch); 333 if (dn->dn_bonus) { 334 mutex_enter(&dn->dn_bonus->db_mtx); 335 dbuf_evict(dn->dn_bonus); 336 dn->dn_bonus = NULL; 337 } 338 kmem_cache_free(dnode_cache, dn); 339 arc_space_return(sizeof (dnode_t)); 340 } 341 342 void 343 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 344 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 345 { 346 int i; 347 348 if (blocksize == 0) 349 blocksize = 1 << zfs_default_bs; 350 else if (blocksize > SPA_MAXBLOCKSIZE) 351 blocksize = SPA_MAXBLOCKSIZE; 352 else 353 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 354 355 if (ibs == 0) 356 ibs = zfs_default_ibs; 357 358 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 359 360 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 361 dn->dn_object, tx->tx_txg, blocksize, ibs); 362 363 ASSERT(dn->dn_type == DMU_OT_NONE); 364 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 365 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 366 ASSERT(ot != DMU_OT_NONE); 367 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 368 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 369 (bonustype != DMU_OT_NONE && bonuslen != 0)); 370 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 371 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 372 ASSERT(dn->dn_type == DMU_OT_NONE); 373 ASSERT3U(dn->dn_maxblkid, ==, 0); 374 ASSERT3U(dn->dn_allocated_txg, ==, 0); 375 ASSERT3U(dn->dn_assigned_txg, ==, 0); 376 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 377 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 378 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 379 380 for (i = 0; i < TXG_SIZE; i++) { 381 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 382 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 383 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 384 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 385 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 386 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 387 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 388 } 389 390 dn->dn_type = ot; 391 dnode_setdblksz(dn, blocksize); 392 dn->dn_indblkshift = ibs; 393 dn->dn_nlevels = 1; 394 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 395 dn->dn_bonustype = bonustype; 396 dn->dn_bonuslen = bonuslen; 397 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 398 dn->dn_compress = ZIO_COMPRESS_INHERIT; 399 dn->dn_dirtyctx = 0; 400 401 dn->dn_free_txg = 0; 402 if (dn->dn_dirtyctx_firstset) { 403 kmem_free(dn->dn_dirtyctx_firstset, 1); 404 dn->dn_dirtyctx_firstset = NULL; 405 } 406 407 dn->dn_allocated_txg = tx->tx_txg; 408 409 dnode_setdirty(dn, tx); 410 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 411 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 412 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 413 } 414 415 void 416 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 417 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 418 { 419 int i, old_nblkptr; 420 dmu_buf_impl_t *db = NULL; 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 for (i = 0; i < TXG_SIZE; i++) 433 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 434 435 /* clean up any unreferenced dbufs */ 436 dnode_evict_dbufs(dn); 437 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 438 439 /* 440 * XXX I should really have a generation number to tell if we 441 * need to do this... 442 */ 443 if (blocksize != dn->dn_datablksz || 444 dn->dn_bonustype != bonustype || dn->dn_bonuslen != bonuslen) { 445 /* free all old data */ 446 dnode_free_range(dn, 0, -1ULL, tx); 447 } 448 449 /* change blocksize */ 450 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 451 if (blocksize != dn->dn_datablksz && 452 (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 453 list_head(&dn->dn_dbufs) != NULL)) { 454 db = dbuf_hold(dn, 0, FTAG); 455 dbuf_new_size(db, blocksize, tx); 456 } 457 dnode_setdblksz(dn, blocksize); 458 dnode_setdirty(dn, tx); 459 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 460 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 461 rw_exit(&dn->dn_struct_rwlock); 462 if (db) 463 dbuf_rele(db, FTAG); 464 465 /* change type */ 466 dn->dn_type = ot; 467 468 /* change bonus size and type */ 469 mutex_enter(&dn->dn_mtx); 470 old_nblkptr = dn->dn_nblkptr; 471 dn->dn_bonustype = bonustype; 472 dn->dn_bonuslen = bonuslen; 473 dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 474 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 475 dn->dn_compress = ZIO_COMPRESS_INHERIT; 476 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 477 478 /* XXX - for now, we can't make nblkptr smaller */ 479 ASSERT3U(dn->dn_nblkptr, >=, old_nblkptr); 480 481 /* fix up the bonus db_size if dn_nblkptr has changed */ 482 if (dn->dn_bonus && dn->dn_bonuslen != old_nblkptr) { 483 dn->dn_bonus->db.db_size = 484 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 485 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 486 } 487 488 dn->dn_allocated_txg = tx->tx_txg; 489 mutex_exit(&dn->dn_mtx); 490 } 491 492 void 493 dnode_special_close(dnode_t *dn) 494 { 495 /* 496 * Wait for final references to the dnode to clear. This can 497 * only happen if the arc is asyncronously evicting state that 498 * has a hold on this dnode while we are trying to evict this 499 * dnode. 500 */ 501 while (refcount_count(&dn->dn_holds) > 0) 502 delay(1); 503 dnode_destroy(dn); 504 } 505 506 dnode_t * 507 dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 508 { 509 dnode_t *dn = dnode_create(os, dnp, NULL, object); 510 DNODE_VERIFY(dn); 511 return (dn); 512 } 513 514 static void 515 dnode_buf_pageout(dmu_buf_t *db, void *arg) 516 { 517 dnode_t **children_dnodes = arg; 518 int i; 519 int epb = db->db_size >> DNODE_SHIFT; 520 521 for (i = 0; i < epb; i++) { 522 dnode_t *dn = children_dnodes[i]; 523 int n; 524 525 if (dn == NULL) 526 continue; 527 #ifdef ZFS_DEBUG 528 /* 529 * If there are holds on this dnode, then there should 530 * be holds on the dnode's containing dbuf as well; thus 531 * it wouldn't be eligable for eviction and this function 532 * would not have been called. 533 */ 534 ASSERT(refcount_is_zero(&dn->dn_holds)); 535 ASSERT(list_head(&dn->dn_dbufs) == NULL); 536 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 537 538 for (n = 0; n < TXG_SIZE; n++) 539 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 540 #endif 541 children_dnodes[i] = NULL; 542 dnode_destroy(dn); 543 } 544 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 545 } 546 547 /* 548 * errors: 549 * EINVAL - invalid object number. 550 * EIO - i/o error. 551 * succeeds even for free dnodes. 552 */ 553 int 554 dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 555 void *tag, dnode_t **dnp) 556 { 557 int epb, idx, err; 558 int drop_struct_lock = FALSE; 559 int type; 560 uint64_t blk; 561 dnode_t *mdn, *dn; 562 dmu_buf_impl_t *db; 563 dnode_t **children_dnodes; 564 565 if (object == 0 || object >= DN_MAX_OBJECT) 566 return (EINVAL); 567 568 mdn = os->os_meta_dnode; 569 570 DNODE_VERIFY(mdn); 571 572 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 573 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 574 drop_struct_lock = TRUE; 575 } 576 577 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 578 579 db = dbuf_hold(mdn, blk, FTAG); 580 if (drop_struct_lock) 581 rw_exit(&mdn->dn_struct_rwlock); 582 if (db == NULL) 583 return (EIO); 584 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 585 if (err) { 586 dbuf_rele(db, FTAG); 587 return (err); 588 } 589 590 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 591 epb = db->db.db_size >> DNODE_SHIFT; 592 593 idx = object & (epb-1); 594 595 children_dnodes = dmu_buf_get_user(&db->db); 596 if (children_dnodes == NULL) { 597 dnode_t **winner; 598 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 599 KM_SLEEP); 600 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 601 dnode_buf_pageout)) { 602 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 603 children_dnodes = winner; 604 } 605 } 606 607 if ((dn = children_dnodes[idx]) == NULL) { 608 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 609 dnode_t *winner; 610 611 dn = dnode_create(os, dnp, db, object); 612 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 613 if (winner != NULL) { 614 dnode_destroy(dn); 615 dn = winner; 616 } 617 } 618 619 mutex_enter(&dn->dn_mtx); 620 type = dn->dn_type; 621 if (dn->dn_free_txg || 622 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 623 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 624 mutex_exit(&dn->dn_mtx); 625 dbuf_rele(db, FTAG); 626 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 627 } 628 mutex_exit(&dn->dn_mtx); 629 630 if (refcount_add(&dn->dn_holds, tag) == 1) 631 dbuf_add_ref(db, dn); 632 633 DNODE_VERIFY(dn); 634 ASSERT3P(dn->dn_dbuf, ==, db); 635 ASSERT3U(dn->dn_object, ==, object); 636 dbuf_rele(db, FTAG); 637 638 *dnp = dn; 639 return (0); 640 } 641 642 /* 643 * Return held dnode if the object is allocated, NULL if not. 644 */ 645 int 646 dnode_hold(objset_impl_t *os, uint64_t object, void *tag, dnode_t **dnp) 647 { 648 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 649 } 650 651 /* 652 * Can only add a reference if there is already at least one 653 * reference on the dnode. Returns FALSE if unable to add a 654 * new reference. 655 */ 656 boolean_t 657 dnode_add_ref(dnode_t *dn, void *tag) 658 { 659 mutex_enter(&dn->dn_mtx); 660 if (refcount_is_zero(&dn->dn_holds)) { 661 mutex_exit(&dn->dn_mtx); 662 return (FALSE); 663 } 664 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 665 mutex_exit(&dn->dn_mtx); 666 return (TRUE); 667 } 668 669 void 670 dnode_rele(dnode_t *dn, void *tag) 671 { 672 uint64_t refs; 673 674 mutex_enter(&dn->dn_mtx); 675 refs = refcount_remove(&dn->dn_holds, tag); 676 mutex_exit(&dn->dn_mtx); 677 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 678 if (refs == 0 && dn->dn_dbuf) 679 dbuf_rele(dn->dn_dbuf, dn); 680 } 681 682 void 683 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 684 { 685 objset_impl_t *os = dn->dn_objset; 686 uint64_t txg = tx->tx_txg; 687 688 if (dn->dn_object == DMU_META_DNODE_OBJECT) 689 return; 690 691 DNODE_VERIFY(dn); 692 693 #ifdef ZFS_DEBUG 694 mutex_enter(&dn->dn_mtx); 695 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 696 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 697 mutex_exit(&dn->dn_mtx); 698 #endif 699 700 mutex_enter(&os->os_lock); 701 702 /* 703 * If we are already marked dirty, we're done. 704 */ 705 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 706 mutex_exit(&os->os_lock); 707 return; 708 } 709 710 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 711 ASSERT(dn->dn_datablksz != 0); 712 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 713 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 714 715 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 716 dn->dn_object, txg); 717 718 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 719 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 720 } else { 721 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 722 } 723 724 mutex_exit(&os->os_lock); 725 726 /* 727 * The dnode maintains a hold on its containing dbuf as 728 * long as there are holds on it. Each instantiated child 729 * dbuf maintaines a hold on the dnode. When the last child 730 * drops its hold, the dnode will drop its hold on the 731 * containing dbuf. We add a "dirty hold" here so that the 732 * dnode will hang around after we finish processing its 733 * children. 734 */ 735 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 736 737 (void) dbuf_dirty(dn->dn_dbuf, tx); 738 739 dsl_dataset_dirty(os->os_dsl_dataset, tx); 740 } 741 742 void 743 dnode_free(dnode_t *dn, dmu_tx_t *tx) 744 { 745 int txgoff = tx->tx_txg & TXG_MASK; 746 747 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 748 749 /* we should be the only holder... hopefully */ 750 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 751 752 mutex_enter(&dn->dn_mtx); 753 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 754 mutex_exit(&dn->dn_mtx); 755 return; 756 } 757 dn->dn_free_txg = tx->tx_txg; 758 mutex_exit(&dn->dn_mtx); 759 760 /* 761 * If the dnode is already dirty, it needs to be moved from 762 * the dirty list to the free list. 763 */ 764 mutex_enter(&dn->dn_objset->os_lock); 765 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 766 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 767 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 768 mutex_exit(&dn->dn_objset->os_lock); 769 } else { 770 mutex_exit(&dn->dn_objset->os_lock); 771 dnode_setdirty(dn, tx); 772 } 773 } 774 775 /* 776 * Try to change the block size for the indicated dnode. This can only 777 * succeed if there are no blocks allocated or dirty beyond first block 778 */ 779 int 780 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 781 { 782 dmu_buf_impl_t *db, *db_next; 783 int have_db0 = FALSE; 784 785 if (size == 0) 786 size = SPA_MINBLOCKSIZE; 787 if (size > SPA_MAXBLOCKSIZE) 788 size = SPA_MAXBLOCKSIZE; 789 else 790 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 791 792 if (ibs == dn->dn_indblkshift) 793 ibs = 0; 794 795 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 796 return (0); 797 798 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 799 800 /* Check for any allocated blocks beyond the first */ 801 if (dn->dn_phys->dn_maxblkid != 0) 802 goto fail; 803 804 mutex_enter(&dn->dn_dbufs_mtx); 805 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 806 db_next = list_next(&dn->dn_dbufs, db); 807 808 if (db->db_blkid == 0) { 809 have_db0 = TRUE; 810 } else if (db->db_blkid != DB_BONUS_BLKID) { 811 mutex_exit(&dn->dn_dbufs_mtx); 812 goto fail; 813 } 814 } 815 mutex_exit(&dn->dn_dbufs_mtx); 816 817 if (ibs && dn->dn_nlevels != 1) 818 goto fail; 819 820 db = NULL; 821 if (!BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || have_db0) { 822 /* obtain the old block */ 823 db = dbuf_hold(dn, 0, FTAG); 824 dbuf_new_size(db, size, tx); 825 } 826 827 dnode_setdblksz(dn, size); 828 dnode_setdirty(dn, tx); 829 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 830 if (ibs) { 831 dn->dn_indblkshift = ibs; 832 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 833 } 834 835 if (db) 836 dbuf_rele(db, FTAG); 837 838 rw_exit(&dn->dn_struct_rwlock); 839 return (0); 840 841 fail: 842 rw_exit(&dn->dn_struct_rwlock); 843 return (ENOTSUP); 844 } 845 846 void 847 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx) 848 { 849 uint64_t txgoff = tx->tx_txg & TXG_MASK; 850 int drop_struct_lock = FALSE; 851 int epbs, new_nlevels; 852 uint64_t sz; 853 854 ASSERT(blkid != DB_BONUS_BLKID); 855 856 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 857 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 858 drop_struct_lock = TRUE; 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 (drop_struct_lock) 911 rw_exit(&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, head; 973 int trunc = FALSE; 974 975 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 976 blksz = dn->dn_datablksz; 977 978 /* If the range is past the end of the file, this is a no-op */ 979 if (off >= blksz * (dn->dn_maxblkid+1)) 980 goto out; 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 } else { 993 ASSERT(dn->dn_maxblkid == 0); 994 if (off == 0 && len >= blksz) { 995 /* Freeing the whole block; don't do any head. */ 996 head = 0; 997 } else { 998 /* Freeing part of the block. */ 999 head = blksz - off; 1000 ASSERT3U(head, >, 0); 1001 } 1002 blkoff = off; 1003 } 1004 /* zero out any partial block data at the start of the range */ 1005 if (head) { 1006 ASSERT3U(blkoff + head, ==, blksz); 1007 if (len < head) 1008 head = len; 1009 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1010 FTAG, &db) == 0) { 1011 caddr_t data; 1012 1013 /* don't dirty if it isn't on disk and isn't dirty */ 1014 if (db->db_last_dirty || 1015 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1016 rw_exit(&dn->dn_struct_rwlock); 1017 dbuf_will_dirty(db, tx); 1018 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1019 data = db->db.db_data; 1020 bzero(data + blkoff, head); 1021 } 1022 dbuf_rele(db, FTAG); 1023 } 1024 off += head; 1025 len -= head; 1026 } 1027 1028 /* If the range was less than one block, we're done */ 1029 if (len == 0 || off >= blksz * (dn->dn_maxblkid+1)) 1030 goto out; 1031 1032 if (!ISP2(blksz)) { 1033 /* 1034 * They are freeing the whole block of a 1035 * non-power-of-two blocksize file. Skip all the messy 1036 * math. 1037 */ 1038 ASSERT3U(off, ==, 0); 1039 ASSERT3U(len, >=, blksz); 1040 blkid = 0; 1041 nblks = 1; 1042 } else { 1043 int tail; 1044 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1045 int blkshift = dn->dn_datablkshift; 1046 1047 /* If the remaining range is past end of file, we're done */ 1048 if (off > dn->dn_maxblkid << blkshift) 1049 goto out; 1050 1051 if (off + len == UINT64_MAX) 1052 tail = 0; 1053 else 1054 tail = P2PHASE(len, blksz); 1055 1056 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1057 /* zero out any partial block data at the end of the range */ 1058 if (tail) { 1059 if (len < tail) 1060 tail = len; 1061 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1062 TRUE, FTAG, &db) == 0) { 1063 /* don't dirty if not on disk and not dirty */ 1064 if (db->db_last_dirty || 1065 (db->db_blkptr && 1066 !BP_IS_HOLE(db->db_blkptr))) { 1067 rw_exit(&dn->dn_struct_rwlock); 1068 dbuf_will_dirty(db, tx); 1069 rw_enter(&dn->dn_struct_rwlock, 1070 RW_WRITER); 1071 bzero(db->db.db_data, tail); 1072 } 1073 dbuf_rele(db, FTAG); 1074 } 1075 len -= tail; 1076 } 1077 /* If the range did not include a full block, we are done */ 1078 if (len == 0) 1079 goto out; 1080 1081 /* dirty the left indirects */ 1082 if (dn->dn_nlevels > 1 && off != 0) { 1083 db = dbuf_hold_level(dn, 1, 1084 (off - head) >> (blkshift + epbs), FTAG); 1085 dbuf_will_dirty(db, tx); 1086 dbuf_rele(db, FTAG); 1087 } 1088 1089 /* dirty the right indirects */ 1090 if (dn->dn_nlevels > 1 && !trunc) { 1091 db = dbuf_hold_level(dn, 1, 1092 (off + len + tail - 1) >> (blkshift + epbs), FTAG); 1093 dbuf_will_dirty(db, tx); 1094 dbuf_rele(db, FTAG); 1095 } 1096 1097 /* 1098 * Finally, add this range to the dnode range list, we 1099 * will finish up this free operation in the syncing phase. 1100 */ 1101 ASSERT(IS_P2ALIGNED(off, 1<<blkshift)); 1102 ASSERT(off + len == UINT64_MAX || 1103 IS_P2ALIGNED(len, 1<<blkshift)); 1104 blkid = off >> blkshift; 1105 nblks = len >> blkshift; 1106 1107 if (trunc) 1108 dn->dn_maxblkid = (blkid ? blkid - 1 : 0); 1109 } 1110 1111 mutex_enter(&dn->dn_mtx); 1112 dnode_clear_range(dn, blkid, nblks, tx); 1113 { 1114 free_range_t *rp, *found; 1115 avl_index_t where; 1116 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1117 1118 /* Add new range to dn_ranges */ 1119 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1120 rp->fr_blkid = blkid; 1121 rp->fr_nblks = nblks; 1122 found = avl_find(tree, rp, &where); 1123 ASSERT(found == NULL); 1124 avl_insert(tree, rp, where); 1125 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1126 blkid, nblks, tx->tx_txg); 1127 } 1128 mutex_exit(&dn->dn_mtx); 1129 1130 dbuf_free_range(dn, blkid, nblks, tx); 1131 dnode_setdirty(dn, tx); 1132 out: 1133 rw_exit(&dn->dn_struct_rwlock); 1134 } 1135 1136 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1137 uint64_t 1138 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1139 { 1140 free_range_t range_tofind; 1141 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1142 int i; 1143 1144 if (blkid == DB_BONUS_BLKID) 1145 return (FALSE); 1146 1147 /* 1148 * If we're in the process of opening the pool, dp will not be 1149 * set yet, but there shouldn't be anything dirty. 1150 */ 1151 if (dp == NULL) 1152 return (FALSE); 1153 1154 if (dn->dn_free_txg) 1155 return (TRUE); 1156 1157 /* 1158 * If dn_datablkshift is not set, then there's only a single 1159 * block, in which case there will never be a free range so it 1160 * won't matter. 1161 */ 1162 range_tofind.fr_blkid = blkid; 1163 mutex_enter(&dn->dn_mtx); 1164 for (i = 0; i < TXG_SIZE; i++) { 1165 free_range_t *range_found; 1166 avl_index_t idx; 1167 1168 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1169 if (range_found) { 1170 ASSERT(range_found->fr_nblks > 0); 1171 break; 1172 } 1173 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1174 if (range_found && 1175 range_found->fr_blkid + range_found->fr_nblks > blkid) 1176 break; 1177 } 1178 mutex_exit(&dn->dn_mtx); 1179 return (i < TXG_SIZE); 1180 } 1181 1182 /* call from syncing context when we actually write/free space for this dnode */ 1183 void 1184 dnode_diduse_space(dnode_t *dn, int64_t delta) 1185 { 1186 uint64_t space; 1187 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1188 dn, dn->dn_phys, 1189 (u_longlong_t)dn->dn_phys->dn_used, 1190 (longlong_t)delta); 1191 1192 mutex_enter(&dn->dn_mtx); 1193 space = DN_USED_BYTES(dn->dn_phys); 1194 if (delta > 0) { 1195 ASSERT3U(space + delta, >=, space); /* no overflow */ 1196 } else { 1197 ASSERT3U(space, >=, -delta); /* no underflow */ 1198 } 1199 space += delta; 1200 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1201 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1202 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1203 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1204 } else { 1205 dn->dn_phys->dn_used = space; 1206 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1207 } 1208 mutex_exit(&dn->dn_mtx); 1209 } 1210 1211 /* 1212 * Call when we think we're going to write/free space in open context. 1213 * Be conservative (ie. OK to write less than this or free more than 1214 * this, but don't write more or free less). 1215 */ 1216 void 1217 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1218 { 1219 objset_impl_t *os = dn->dn_objset; 1220 dsl_dataset_t *ds = os->os_dsl_dataset; 1221 1222 if (space > 0) 1223 space = spa_get_asize(os->os_spa, space); 1224 1225 if (ds) 1226 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1227 1228 dmu_tx_willuse_space(tx, space); 1229 } 1230 1231 static int 1232 dnode_next_offset_level(dnode_t *dn, boolean_t hole, uint64_t *offset, 1233 int lvl, uint64_t blkfill, uint64_t txg) 1234 { 1235 dmu_buf_impl_t *db = NULL; 1236 void *data = NULL; 1237 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1238 uint64_t epb = 1ULL << epbs; 1239 uint64_t minfill, maxfill; 1240 int i, error, span; 1241 1242 dprintf("probing object %llu offset %llx level %d of %u\n", 1243 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1244 1245 if (lvl == dn->dn_phys->dn_nlevels) { 1246 error = 0; 1247 epb = dn->dn_phys->dn_nblkptr; 1248 data = dn->dn_phys->dn_blkptr; 1249 } else { 1250 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1251 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1252 if (error) { 1253 if (error == ENOENT) 1254 return (hole ? 0 : ESRCH); 1255 return (error); 1256 } 1257 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1258 if (error) { 1259 dbuf_rele(db, FTAG); 1260 return (error); 1261 } 1262 data = db->db.db_data; 1263 } 1264 1265 if (db && txg && 1266 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1267 error = ESRCH; 1268 } else if (lvl == 0) { 1269 dnode_phys_t *dnp = data; 1270 span = DNODE_SHIFT; 1271 ASSERT(dn->dn_type == DMU_OT_DNODE); 1272 1273 for (i = (*offset >> span) & (blkfill - 1); i < blkfill; i++) { 1274 boolean_t newcontents = B_TRUE; 1275 if (txg) { 1276 int j; 1277 newcontents = B_FALSE; 1278 for (j = 0; j < dnp[i].dn_nblkptr; j++) { 1279 if (dnp[i].dn_blkptr[j].blk_birth > txg) 1280 newcontents = B_TRUE; 1281 } 1282 } 1283 if (!dnp[i].dn_type == hole && newcontents) 1284 break; 1285 *offset += 1ULL << span; 1286 } 1287 if (i == blkfill) 1288 error = ESRCH; 1289 } else { 1290 blkptr_t *bp = data; 1291 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1292 minfill = 0; 1293 maxfill = blkfill << ((lvl - 1) * epbs); 1294 1295 if (hole) 1296 maxfill--; 1297 else 1298 minfill++; 1299 1300 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1301 i < epb; i++) { 1302 if (bp[i].blk_fill >= minfill && 1303 bp[i].blk_fill <= maxfill && 1304 bp[i].blk_birth > txg) 1305 break; 1306 *offset += 1ULL << span; 1307 } 1308 if (i >= epb) 1309 error = ESRCH; 1310 } 1311 1312 if (db) 1313 dbuf_rele(db, FTAG); 1314 1315 return (error); 1316 } 1317 1318 /* 1319 * Find the next hole, data, or sparse region at or after *offset. 1320 * The value 'blkfill' tells us how many items we expect to find 1321 * in an L0 data block; this value is 1 for normal objects, 1322 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1323 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1324 * 1325 * Examples: 1326 * 1327 * dnode_next_offset(dn, hole, offset, 1, 1, 0); 1328 * Finds the next hole/data in a file. 1329 * Used in dmu_offset_next(). 1330 * 1331 * dnode_next_offset(mdn, hole, offset, 0, DNODES_PER_BLOCK, txg); 1332 * Finds the next free/allocated dnode an objset's meta-dnode. 1333 * Only finds objects that have new contents since txg (ie. 1334 * bonus buffer changes and content removal are ignored). 1335 * Used in dmu_object_next(). 1336 * 1337 * dnode_next_offset(mdn, TRUE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1338 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1339 * Used in dmu_object_alloc(). 1340 */ 1341 int 1342 dnode_next_offset(dnode_t *dn, boolean_t hole, uint64_t *offset, 1343 int minlvl, uint64_t blkfill, uint64_t txg) 1344 { 1345 int lvl, maxlvl; 1346 int error = 0; 1347 uint64_t initial_offset = *offset; 1348 1349 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1350 1351 if (dn->dn_phys->dn_nlevels == 0) { 1352 rw_exit(&dn->dn_struct_rwlock); 1353 return (ESRCH); 1354 } 1355 1356 if (dn->dn_datablkshift == 0) { 1357 if (*offset < dn->dn_datablksz) { 1358 if (hole) 1359 *offset = dn->dn_datablksz; 1360 } else { 1361 error = ESRCH; 1362 } 1363 rw_exit(&dn->dn_struct_rwlock); 1364 return (error); 1365 } 1366 1367 maxlvl = dn->dn_phys->dn_nlevels; 1368 1369 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1370 error = dnode_next_offset_level(dn, 1371 hole, offset, lvl, blkfill, txg); 1372 if (error != ESRCH) 1373 break; 1374 } 1375 1376 while (--lvl >= minlvl && error == 0) { 1377 error = dnode_next_offset_level(dn, 1378 hole, offset, lvl, blkfill, txg); 1379 } 1380 1381 rw_exit(&dn->dn_struct_rwlock); 1382 1383 if (error == 0 && initial_offset > *offset) 1384 error = ESRCH; 1385 1386 return (error); 1387 } 1388
Indexes created Mon Nov 23 18:03:40 UTC 2009
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