dnode.c revision 208372
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 2008 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 39static int free_range_compar(const void *node1, const void *node2); 40 41static kmem_cache_t *dnode_cache; 42 43static dnode_phys_t dnode_phys_zero; 44 45int zfs_default_bs = SPA_MINBLOCKSHIFT; 46int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 47 48/* ARGSUSED */ 49static int 50dnode_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 */ 80static void 81dnode_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 101void 102dnode_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 109void 110dnode_fini(void) 111{ 112 kmem_cache_destroy(dnode_cache); 113} 114 115 116#ifdef ZFS_DEBUG 117void 118dnode_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 170void 171dnode_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 215void 216dnode_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 231static int 232free_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 244void 245dnode_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 261static void 262dnode_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 274static dnode_t * 275dnode_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); 279 280 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 308static void 309dnode_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 342void 343dnode_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 415void 416dnode_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 nblkptr; 420 421 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 422 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 423 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 424 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 425 ASSERT(tx->tx_txg != 0); 426 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 427 (bonustype != DMU_OT_NONE && bonuslen != 0)); 428 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 429 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 430 431 /* clean up any unreferenced dbufs */ 432 dnode_evict_dbufs(dn); 433 434 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 435 dnode_setdirty(dn, tx); 436 if (dn->dn_datablksz != blocksize) { 437 /* change blocksize */ 438 ASSERT(dn->dn_maxblkid == 0 && 439 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 440 dnode_block_freed(dn, 0))); 441 dnode_setdblksz(dn, blocksize); 442 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 443 } 444 if (dn->dn_bonuslen != bonuslen) 445 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 446 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 447 if (dn->dn_nblkptr != nblkptr) 448 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 449 rw_exit(&dn->dn_struct_rwlock); 450 451 /* change type */ 452 dn->dn_type = ot; 453 454 /* change bonus size and type */ 455 mutex_enter(&dn->dn_mtx); 456 dn->dn_bonustype = bonustype; 457 dn->dn_bonuslen = bonuslen; 458 dn->dn_nblkptr = nblkptr; 459 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 460 dn->dn_compress = ZIO_COMPRESS_INHERIT; 461 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 462 463 /* fix up the bonus db_size */ 464 if (dn->dn_bonus) { 465 dn->dn_bonus->db.db_size = 466 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 467 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 468 } 469 470 dn->dn_allocated_txg = tx->tx_txg; 471 mutex_exit(&dn->dn_mtx); 472} 473 474void 475dnode_special_close(dnode_t *dn) 476{ 477 /* 478 * Wait for final references to the dnode to clear. This can 479 * only happen if the arc is asyncronously evicting state that 480 * has a hold on this dnode while we are trying to evict this 481 * dnode. 482 */ 483 while (refcount_count(&dn->dn_holds) > 0) 484 delay(1); 485 dnode_destroy(dn); 486} 487 488dnode_t * 489dnode_special_open(objset_impl_t *os, dnode_phys_t *dnp, uint64_t object) 490{ 491 dnode_t *dn = dnode_create(os, dnp, NULL, object); 492 DNODE_VERIFY(dn); 493 return (dn); 494} 495 496static void 497dnode_buf_pageout(dmu_buf_t *db, void *arg) 498{ 499 dnode_t **children_dnodes = arg; 500 int i; 501 int epb = db->db_size >> DNODE_SHIFT; 502 503 for (i = 0; i < epb; i++) { 504 dnode_t *dn = children_dnodes[i]; 505 int n; 506 507 if (dn == NULL) 508 continue; 509#ifdef ZFS_DEBUG 510 /* 511 * If there are holds on this dnode, then there should 512 * be holds on the dnode's containing dbuf as well; thus 513 * it wouldn't be eligable for eviction and this function 514 * would not have been called. 515 */ 516 ASSERT(refcount_is_zero(&dn->dn_holds)); 517 ASSERT(list_head(&dn->dn_dbufs) == NULL); 518 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 519 520 for (n = 0; n < TXG_SIZE; n++) 521 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 522#endif 523 children_dnodes[i] = NULL; 524 dnode_destroy(dn); 525 } 526 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 527} 528 529/* 530 * errors: 531 * EINVAL - invalid object number. 532 * EIO - i/o error. 533 * succeeds even for free dnodes. 534 */ 535int 536dnode_hold_impl(objset_impl_t *os, uint64_t object, int flag, 537 void *tag, dnode_t **dnp) 538{ 539 int epb, idx, err; 540 int drop_struct_lock = FALSE; 541 int type; 542 uint64_t blk; 543 dnode_t *mdn, *dn; 544 dmu_buf_impl_t *db; 545 dnode_t **children_dnodes; 546 547 /* 548 * If you are holding the spa config lock as writer, you shouldn't 549 * be asking the DMU to do *anything*. 550 */ 551 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0); 552 553 if (object == 0 || object >= DN_MAX_OBJECT) 554 return (EINVAL); 555 556 mdn = os->os_meta_dnode; 557 558 DNODE_VERIFY(mdn); 559 560 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 561 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 562 drop_struct_lock = TRUE; 563 } 564 565 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 566 567 db = dbuf_hold(mdn, blk, FTAG); 568 if (drop_struct_lock) 569 rw_exit(&mdn->dn_struct_rwlock); 570 if (db == NULL) 571 return (EIO); 572 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 573 if (err) { 574 dbuf_rele(db, FTAG); 575 return (err); 576 } 577 578 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 579 epb = db->db.db_size >> DNODE_SHIFT; 580 581 idx = object & (epb-1); 582 583 children_dnodes = dmu_buf_get_user(&db->db); 584 if (children_dnodes == NULL) { 585 dnode_t **winner; 586 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 587 KM_SLEEP); 588 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 589 dnode_buf_pageout)) { 590 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 591 children_dnodes = winner; 592 } 593 } 594 595 if ((dn = children_dnodes[idx]) == NULL) { 596 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 597 dnode_t *winner; 598 599 dn = dnode_create(os, dnp, db, object); 600 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 601 if (winner != NULL) { 602 dnode_destroy(dn); 603 dn = winner; 604 } 605 } 606 607 mutex_enter(&dn->dn_mtx); 608 type = dn->dn_type; 609 if (dn->dn_free_txg || 610 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 611 ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE)) { 612 mutex_exit(&dn->dn_mtx); 613 dbuf_rele(db, FTAG); 614 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 615 } 616 mutex_exit(&dn->dn_mtx); 617 618 if (refcount_add(&dn->dn_holds, tag) == 1) 619 dbuf_add_ref(db, dn); 620 621 DNODE_VERIFY(dn); 622 ASSERT3P(dn->dn_dbuf, ==, db); 623 ASSERT3U(dn->dn_object, ==, object); 624 dbuf_rele(db, FTAG); 625 626 *dnp = dn; 627 return (0); 628} 629 630/* 631 * Return held dnode if the object is allocated, NULL if not. 632 */ 633int 634dnode_hold(objset_impl_t *os, uint64_t object, void *tag, dnode_t **dnp) 635{ 636 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 637} 638 639/* 640 * Can only add a reference if there is already at least one 641 * reference on the dnode. Returns FALSE if unable to add a 642 * new reference. 643 */ 644boolean_t 645dnode_add_ref(dnode_t *dn, void *tag) 646{ 647 mutex_enter(&dn->dn_mtx); 648 if (refcount_is_zero(&dn->dn_holds)) { 649 mutex_exit(&dn->dn_mtx); 650 return (FALSE); 651 } 652 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 653 mutex_exit(&dn->dn_mtx); 654 return (TRUE); 655} 656 657void 658dnode_rele(dnode_t *dn, void *tag) 659{ 660 uint64_t refs; 661 662 mutex_enter(&dn->dn_mtx); 663 refs = refcount_remove(&dn->dn_holds, tag); 664 mutex_exit(&dn->dn_mtx); 665 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 666 if (refs == 0 && dn->dn_dbuf) 667 dbuf_rele(dn->dn_dbuf, dn); 668} 669 670void 671dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 672{ 673 objset_impl_t *os = dn->dn_objset; 674 uint64_t txg = tx->tx_txg; 675 676 if (dn->dn_object == DMU_META_DNODE_OBJECT) 677 return; 678 679 DNODE_VERIFY(dn); 680 681#ifdef ZFS_DEBUG 682 mutex_enter(&dn->dn_mtx); 683 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 684 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 685 mutex_exit(&dn->dn_mtx); 686#endif 687 688 mutex_enter(&os->os_lock); 689 690 /* 691 * If we are already marked dirty, we're done. 692 */ 693 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 694 mutex_exit(&os->os_lock); 695 return; 696 } 697 698 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 699 ASSERT(dn->dn_datablksz != 0); 700 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 701 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 702 703 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 704 dn->dn_object, txg); 705 706 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 707 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 708 } else { 709 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 710 } 711 712 mutex_exit(&os->os_lock); 713 714 /* 715 * The dnode maintains a hold on its containing dbuf as 716 * long as there are holds on it. Each instantiated child 717 * dbuf maintaines a hold on the dnode. When the last child 718 * drops its hold, the dnode will drop its hold on the 719 * containing dbuf. We add a "dirty hold" here so that the 720 * dnode will hang around after we finish processing its 721 * children. 722 */ 723 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 724 725 (void) dbuf_dirty(dn->dn_dbuf, tx); 726 727 dsl_dataset_dirty(os->os_dsl_dataset, tx); 728} 729 730void 731dnode_free(dnode_t *dn, dmu_tx_t *tx) 732{ 733 int txgoff = tx->tx_txg & TXG_MASK; 734 735 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 736 737 /* we should be the only holder... hopefully */ 738 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 739 740 mutex_enter(&dn->dn_mtx); 741 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 742 mutex_exit(&dn->dn_mtx); 743 return; 744 } 745 dn->dn_free_txg = tx->tx_txg; 746 mutex_exit(&dn->dn_mtx); 747 748 /* 749 * If the dnode is already dirty, it needs to be moved from 750 * the dirty list to the free list. 751 */ 752 mutex_enter(&dn->dn_objset->os_lock); 753 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 754 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 755 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 756 mutex_exit(&dn->dn_objset->os_lock); 757 } else { 758 mutex_exit(&dn->dn_objset->os_lock); 759 dnode_setdirty(dn, tx); 760 } 761} 762 763/* 764 * Try to change the block size for the indicated dnode. This can only 765 * succeed if there are no blocks allocated or dirty beyond first block 766 */ 767int 768dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 769{ 770 dmu_buf_impl_t *db, *db_next; 771 int err; 772 773 if (size == 0) 774 size = SPA_MINBLOCKSIZE; 775 if (size > SPA_MAXBLOCKSIZE) 776 size = SPA_MAXBLOCKSIZE; 777 else 778 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 779 780 if (ibs == dn->dn_indblkshift) 781 ibs = 0; 782 783 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 784 return (0); 785 786 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 787 788 /* Check for any allocated blocks beyond the first */ 789 if (dn->dn_phys->dn_maxblkid != 0) 790 goto fail; 791 792 mutex_enter(&dn->dn_dbufs_mtx); 793 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 794 db_next = list_next(&dn->dn_dbufs, db); 795 796 if (db->db_blkid != 0 && db->db_blkid != DB_BONUS_BLKID) { 797 mutex_exit(&dn->dn_dbufs_mtx); 798 goto fail; 799 } 800 } 801 mutex_exit(&dn->dn_dbufs_mtx); 802 803 if (ibs && dn->dn_nlevels != 1) 804 goto fail; 805 806 /* resize the old block */ 807 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 808 if (err == 0) 809 dbuf_new_size(db, size, tx); 810 else if (err != ENOENT) 811 goto fail; 812 813 dnode_setdblksz(dn, size); 814 dnode_setdirty(dn, tx); 815 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 816 if (ibs) { 817 dn->dn_indblkshift = ibs; 818 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 819 } 820 /* rele after we have fixed the blocksize in the dnode */ 821 if (db) 822 dbuf_rele(db, FTAG); 823 824 rw_exit(&dn->dn_struct_rwlock); 825 return (0); 826 827fail: 828 rw_exit(&dn->dn_struct_rwlock); 829 return (ENOTSUP); 830} 831 832/* read-holding callers must not rely on the lock being continuously held */ 833void 834dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 835{ 836 uint64_t txgoff = tx->tx_txg & TXG_MASK; 837 int epbs, new_nlevels; 838 uint64_t sz; 839 840 ASSERT(blkid != DB_BONUS_BLKID); 841 842 ASSERT(have_read ? 843 RW_READ_HELD(&dn->dn_struct_rwlock) : 844 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 845 846 /* 847 * if we have a read-lock, check to see if we need to do any work 848 * before upgrading to a write-lock. 849 */ 850 if (have_read) { 851 if (blkid <= dn->dn_maxblkid) 852 return; 853 854 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 855 rw_exit(&dn->dn_struct_rwlock); 856 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 857 } 858 } 859 860 if (blkid <= dn->dn_maxblkid) 861 goto out; 862 863 dn->dn_maxblkid = blkid; 864 865 /* 866 * Compute the number of levels necessary to support the new maxblkid. 867 */ 868 new_nlevels = 1; 869 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 870 for (sz = dn->dn_nblkptr; 871 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 872 new_nlevels++; 873 874 if (new_nlevels > dn->dn_nlevels) { 875 int old_nlevels = dn->dn_nlevels; 876 dmu_buf_impl_t *db; 877 list_t *list; 878 dbuf_dirty_record_t *new, *dr, *dr_next; 879 880 dn->dn_nlevels = new_nlevels; 881 882 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 883 dn->dn_next_nlevels[txgoff] = new_nlevels; 884 885 /* dirty the left indirects */ 886 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 887 new = dbuf_dirty(db, tx); 888 dbuf_rele(db, FTAG); 889 890 /* transfer the dirty records to the new indirect */ 891 mutex_enter(&dn->dn_mtx); 892 mutex_enter(&new->dt.di.dr_mtx); 893 list = &dn->dn_dirty_records[txgoff]; 894 for (dr = list_head(list); dr; dr = dr_next) { 895 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 896 if (dr->dr_dbuf->db_level != new_nlevels-1 && 897 dr->dr_dbuf->db_blkid != DB_BONUS_BLKID) { 898 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 899 list_remove(&dn->dn_dirty_records[txgoff], dr); 900 list_insert_tail(&new->dt.di.dr_children, dr); 901 dr->dr_parent = new; 902 } 903 } 904 mutex_exit(&new->dt.di.dr_mtx); 905 mutex_exit(&dn->dn_mtx); 906 } 907 908out: 909 if (have_read) 910 rw_downgrade(&dn->dn_struct_rwlock); 911} 912 913void 914dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 915{ 916 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 917 avl_index_t where; 918 free_range_t *rp; 919 free_range_t rp_tofind; 920 uint64_t endblk = blkid + nblks; 921 922 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 923 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 924 925 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 926 blkid, nblks, tx->tx_txg); 927 rp_tofind.fr_blkid = blkid; 928 rp = avl_find(tree, &rp_tofind, &where); 929 if (rp == NULL) 930 rp = avl_nearest(tree, where, AVL_BEFORE); 931 if (rp == NULL) 932 rp = avl_nearest(tree, where, AVL_AFTER); 933 934 while (rp && (rp->fr_blkid <= blkid + nblks)) { 935 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 936 free_range_t *nrp = AVL_NEXT(tree, rp); 937 938 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 939 /* clear this entire range */ 940 avl_remove(tree, rp); 941 kmem_free(rp, sizeof (free_range_t)); 942 } else if (blkid <= rp->fr_blkid && 943 endblk > rp->fr_blkid && endblk < fr_endblk) { 944 /* clear the beginning of this range */ 945 rp->fr_blkid = endblk; 946 rp->fr_nblks = fr_endblk - endblk; 947 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 948 endblk >= fr_endblk) { 949 /* clear the end of this range */ 950 rp->fr_nblks = blkid - rp->fr_blkid; 951 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 952 /* clear a chunk out of this range */ 953 free_range_t *new_rp = 954 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 955 956 new_rp->fr_blkid = endblk; 957 new_rp->fr_nblks = fr_endblk - endblk; 958 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 959 rp->fr_nblks = blkid - rp->fr_blkid; 960 } 961 /* there may be no overlap */ 962 rp = nrp; 963 } 964} 965 966void 967dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 968{ 969 dmu_buf_impl_t *db; 970 uint64_t blkoff, blkid, nblks; 971 int blksz, blkshift, head, tail; 972 int trunc = FALSE; 973 int epbs; 974 975 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 976 blksz = dn->dn_datablksz; 977 blkshift = dn->dn_datablkshift; 978 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 979 980 if (len == -1ULL) { 981 len = UINT64_MAX - off; 982 trunc = TRUE; 983 } 984 985 /* 986 * First, block align the region to free: 987 */ 988 if (ISP2(blksz)) { 989 head = P2NPHASE(off, blksz); 990 blkoff = P2PHASE(off, blksz); 991 if ((off >> blkshift) > dn->dn_maxblkid) 992 goto out; 993 } else { 994 ASSERT(dn->dn_maxblkid == 0); 995 if (off == 0 && len >= blksz) { 996 /* Freeing the whole block; fast-track this request */ 997 blkid = 0; 998 nblks = 1; 999 goto done; 1000 } else if (off >= blksz) { 1001 /* Freeing past end-of-data */ 1002 goto out; 1003 } else { 1004 /* Freeing part of the block. */ 1005 head = blksz - off; 1006 ASSERT3U(head, >, 0); 1007 } 1008 blkoff = off; 1009 } 1010 /* zero out any partial block data at the start of the range */ 1011 if (head) { 1012 ASSERT3U(blkoff + head, ==, blksz); 1013 if (len < head) 1014 head = len; 1015 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1016 FTAG, &db) == 0) { 1017 caddr_t data; 1018 1019 /* don't dirty if it isn't on disk and isn't dirty */ 1020 if (db->db_last_dirty || 1021 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1022 rw_exit(&dn->dn_struct_rwlock); 1023 dbuf_will_dirty(db, tx); 1024 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1025 data = db->db.db_data; 1026 bzero(data + blkoff, head); 1027 } 1028 dbuf_rele(db, FTAG); 1029 } 1030 off += head; 1031 len -= head; 1032 } 1033 1034 /* If the range was less than one block, we're done */ 1035 if (len == 0) 1036 goto out; 1037 1038 /* If the remaining range is past end of file, we're done */ 1039 if ((off >> blkshift) > dn->dn_maxblkid) 1040 goto out; 1041 1042 ASSERT(ISP2(blksz)); 1043 if (trunc) 1044 tail = 0; 1045 else 1046 tail = P2PHASE(len, blksz); 1047 1048 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1049 /* zero out any partial block data at the end of the range */ 1050 if (tail) { 1051 if (len < tail) 1052 tail = len; 1053 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1054 TRUE, FTAG, &db) == 0) { 1055 /* don't dirty if not on disk and not dirty */ 1056 if (db->db_last_dirty || 1057 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1058 rw_exit(&dn->dn_struct_rwlock); 1059 dbuf_will_dirty(db, tx); 1060 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1061 bzero(db->db.db_data, tail); 1062 } 1063 dbuf_rele(db, FTAG); 1064 } 1065 len -= tail; 1066 } 1067 1068 /* If the range did not include a full block, we are done */ 1069 if (len == 0) 1070 goto out; 1071 1072 ASSERT(IS_P2ALIGNED(off, blksz)); 1073 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1074 blkid = off >> blkshift; 1075 nblks = len >> blkshift; 1076 if (trunc) 1077 nblks += 1; 1078 1079 /* 1080 * Read in and mark all the level-1 indirects dirty, 1081 * so that they will stay in memory until syncing phase. 1082 * Always dirty the first and last indirect to make sure 1083 * we dirty all the partial indirects. 1084 */ 1085 if (dn->dn_nlevels > 1) { 1086 uint64_t i, first, last; 1087 int shift = epbs + dn->dn_datablkshift; 1088 1089 first = blkid >> epbs; 1090 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1091 dbuf_will_dirty(db, tx); 1092 dbuf_rele(db, FTAG); 1093 } 1094 if (trunc) 1095 last = dn->dn_maxblkid >> epbs; 1096 else 1097 last = (blkid + nblks - 1) >> epbs; 1098 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1099 dbuf_will_dirty(db, tx); 1100 dbuf_rele(db, FTAG); 1101 } 1102 for (i = first + 1; i < last; i++) { 1103 uint64_t ibyte = i << shift; 1104 int err; 1105 1106 err = dnode_next_offset(dn, 1107 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1108 i = ibyte >> shift; 1109 if (err == ESRCH || i >= last) 1110 break; 1111 ASSERT(err == 0); 1112 db = dbuf_hold_level(dn, 1, i, FTAG); 1113 if (db) { 1114 dbuf_will_dirty(db, tx); 1115 dbuf_rele(db, FTAG); 1116 } 1117 } 1118 } 1119done: 1120 /* 1121 * Add this range to the dnode range list. 1122 * We will finish up this free operation in the syncing phase. 1123 */ 1124 mutex_enter(&dn->dn_mtx); 1125 dnode_clear_range(dn, blkid, nblks, tx); 1126 { 1127 free_range_t *rp, *found; 1128 avl_index_t where; 1129 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1130 1131 /* Add new range to dn_ranges */ 1132 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1133 rp->fr_blkid = blkid; 1134 rp->fr_nblks = nblks; 1135 found = avl_find(tree, rp, &where); 1136 ASSERT(found == NULL); 1137 avl_insert(tree, rp, where); 1138 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1139 blkid, nblks, tx->tx_txg); 1140 } 1141 mutex_exit(&dn->dn_mtx); 1142 1143 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1144 dnode_setdirty(dn, tx); 1145out: 1146 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1147 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1148 1149 rw_exit(&dn->dn_struct_rwlock); 1150} 1151 1152/* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1153uint64_t 1154dnode_block_freed(dnode_t *dn, uint64_t blkid) 1155{ 1156 free_range_t range_tofind; 1157 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1158 int i; 1159 1160 if (blkid == DB_BONUS_BLKID) 1161 return (FALSE); 1162 1163 /* 1164 * If we're in the process of opening the pool, dp will not be 1165 * set yet, but there shouldn't be anything dirty. 1166 */ 1167 if (dp == NULL) 1168 return (FALSE); 1169 1170 if (dn->dn_free_txg) 1171 return (TRUE); 1172 1173 range_tofind.fr_blkid = blkid; 1174 mutex_enter(&dn->dn_mtx); 1175 for (i = 0; i < TXG_SIZE; i++) { 1176 free_range_t *range_found; 1177 avl_index_t idx; 1178 1179 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1180 if (range_found) { 1181 ASSERT(range_found->fr_nblks > 0); 1182 break; 1183 } 1184 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1185 if (range_found && 1186 range_found->fr_blkid + range_found->fr_nblks > blkid) 1187 break; 1188 } 1189 mutex_exit(&dn->dn_mtx); 1190 return (i < TXG_SIZE); 1191} 1192 1193/* call from syncing context when we actually write/free space for this dnode */ 1194void 1195dnode_diduse_space(dnode_t *dn, int64_t delta) 1196{ 1197 uint64_t space; 1198 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1199 dn, dn->dn_phys, 1200 (u_longlong_t)dn->dn_phys->dn_used, 1201 (longlong_t)delta); 1202 1203 mutex_enter(&dn->dn_mtx); 1204 space = DN_USED_BYTES(dn->dn_phys); 1205 if (delta > 0) { 1206 ASSERT3U(space + delta, >=, space); /* no overflow */ 1207 } else { 1208 ASSERT3U(space, >=, -delta); /* no underflow */ 1209 } 1210 space += delta; 1211 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1212 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1213 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1214 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1215 } else { 1216 dn->dn_phys->dn_used = space; 1217 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1218 } 1219 mutex_exit(&dn->dn_mtx); 1220} 1221 1222/* 1223 * Call when we think we're going to write/free space in open context. 1224 * Be conservative (ie. OK to write less than this or free more than 1225 * this, but don't write more or free less). 1226 */ 1227void 1228dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1229{ 1230 objset_impl_t *os = dn->dn_objset; 1231 dsl_dataset_t *ds = os->os_dsl_dataset; 1232 1233 if (space > 0) 1234 space = spa_get_asize(os->os_spa, space); 1235 1236 if (ds) 1237 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1238 1239 dmu_tx_willuse_space(tx, space); 1240} 1241 1242static int 1243dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1244 int lvl, uint64_t blkfill, uint64_t txg) 1245{ 1246 dmu_buf_impl_t *db = NULL; 1247 void *data = NULL; 1248 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1249 uint64_t epb = 1ULL << epbs; 1250 uint64_t minfill, maxfill; 1251 boolean_t hole; 1252 int i, inc, error, span; 1253 1254 dprintf("probing object %llu offset %llx level %d of %u\n", 1255 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1256 1257 hole = flags & DNODE_FIND_HOLE; 1258 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1259 ASSERT(txg == 0 || !hole); 1260 1261 if (lvl == dn->dn_phys->dn_nlevels) { 1262 error = 0; 1263 epb = dn->dn_phys->dn_nblkptr; 1264 data = dn->dn_phys->dn_blkptr; 1265 } else { 1266 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1267 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1268 if (error) { 1269 if (error != ENOENT) 1270 return (error); 1271 if (hole) 1272 return (0); 1273 /* 1274 * This can only happen when we are searching up 1275 * the block tree for data. We don't really need to 1276 * adjust the offset, as we will just end up looking 1277 * at the pointer to this block in its parent, and its 1278 * going to be unallocated, so we will skip over it. 1279 */ 1280 return (ESRCH); 1281 } 1282 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1283 if (error) { 1284 dbuf_rele(db, FTAG); 1285 return (error); 1286 } 1287 data = db->db.db_data; 1288 } 1289 1290 if (db && txg && 1291 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1292 /* 1293 * This can only happen when we are searching up the tree 1294 * and these conditions mean that we need to keep climbing. 1295 */ 1296 error = ESRCH; 1297 } else if (lvl == 0) { 1298 dnode_phys_t *dnp = data; 1299 span = DNODE_SHIFT; 1300 ASSERT(dn->dn_type == DMU_OT_DNODE); 1301 1302 for (i = (*offset >> span) & (blkfill - 1); 1303 i >= 0 && i < blkfill; i += inc) { 1304 boolean_t newcontents = B_TRUE; 1305 if (txg) { 1306 int j; 1307 newcontents = B_FALSE; 1308 for (j = 0; j < dnp[i].dn_nblkptr; j++) { 1309 if (dnp[i].dn_blkptr[j].blk_birth > txg) 1310 newcontents = B_TRUE; 1311 } 1312 } 1313 if (!dnp[i].dn_type == hole && newcontents) 1314 break; 1315 *offset += (1ULL << span) * inc; 1316 } 1317 if (i < 0 || i == blkfill) 1318 error = ESRCH; 1319 } else { 1320 blkptr_t *bp = data; 1321 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1322 minfill = 0; 1323 maxfill = blkfill << ((lvl - 1) * epbs); 1324 1325 if (hole) 1326 maxfill--; 1327 else 1328 minfill++; 1329 1330 for (i = (*offset >> span) & ((1ULL << epbs) - 1); 1331 i >= 0 && i < epb; i += inc) { 1332 if (bp[i].blk_fill >= minfill && 1333 bp[i].blk_fill <= maxfill && 1334 (hole || bp[i].blk_birth > txg)) 1335 break; 1336 if (inc < 0 && *offset < (1ULL << span)) 1337 *offset = 0; 1338 else 1339 *offset += (1ULL << span) * inc; 1340 } 1341 if (i < 0 || i == epb) 1342 error = ESRCH; 1343 } 1344 1345 if (db) 1346 dbuf_rele(db, FTAG); 1347 1348 return (error); 1349} 1350 1351/* 1352 * Find the next hole, data, or sparse region at or after *offset. 1353 * The value 'blkfill' tells us how many items we expect to find 1354 * in an L0 data block; this value is 1 for normal objects, 1355 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1356 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1357 * 1358 * Examples: 1359 * 1360 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1361 * Finds the next/previous hole/data in a file. 1362 * Used in dmu_offset_next(). 1363 * 1364 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1365 * Finds the next free/allocated dnode an objset's meta-dnode. 1366 * Only finds objects that have new contents since txg (ie. 1367 * bonus buffer changes and content removal are ignored). 1368 * Used in dmu_object_next(). 1369 * 1370 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1371 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1372 * Used in dmu_object_alloc(). 1373 */ 1374int 1375dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1376 int minlvl, uint64_t blkfill, uint64_t txg) 1377{ 1378 uint64_t initial_offset = *offset; 1379 int lvl, maxlvl; 1380 int error = 0; 1381 1382 if (!(flags & DNODE_FIND_HAVELOCK)) 1383 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1384 1385 if (dn->dn_phys->dn_nlevels == 0) { 1386 error = ESRCH; 1387 goto out; 1388 } 1389 1390 if (dn->dn_datablkshift == 0) { 1391 if (*offset < dn->dn_datablksz) { 1392 if (flags & DNODE_FIND_HOLE) 1393 *offset = dn->dn_datablksz; 1394 } else { 1395 error = ESRCH; 1396 } 1397 goto out; 1398 } 1399 1400 maxlvl = dn->dn_phys->dn_nlevels; 1401 1402 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1403 error = dnode_next_offset_level(dn, 1404 flags, offset, lvl, blkfill, txg); 1405 if (error != ESRCH) 1406 break; 1407 } 1408 1409 while (error == 0 && --lvl >= minlvl) { 1410 error = dnode_next_offset_level(dn, 1411 flags, offset, lvl, blkfill, txg); 1412 } 1413 1414 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1415 initial_offset < *offset : initial_offset > *offset)) 1416 error = ESRCH; 1417out: 1418 if (!(flags & DNODE_FIND_HAVELOCK)) 1419 rw_exit(&dn->dn_struct_rwlock); 1420 1421 return (error); 1422} 1423