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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 */ 24 25 #include <sys/zfs_context.h> 26 #include <sys/dbuf.h> 27 #include <sys/dnode.h> 28 #include <sys/dmu.h> 29 #include <sys/dmu_impl.h> 30 #include <sys/dmu_tx.h> 31 #include <sys/dmu_objset.h> 32 #include <sys/dsl_dir.h> 33 #include <sys/dsl_dataset.h> 34 #include <sys/spa.h> 35 #include <sys/zio.h> 36 #include <sys/dmu_zfetch.h> 37 38 static int free_range_compar(const void *node1, const void *node2); 39 40 static kmem_cache_t *dnode_cache; 41 42 static dnode_phys_t dnode_phys_zero; 43 44 int zfs_default_bs = SPA_MINBLOCKSHIFT; 45 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 46 47 /* ARGSUSED */ 48 static int 49 dnode_cons(void *arg, void *unused, int kmflag) 50 { 51 int i; 52 dnode_t *dn = arg; 53 bzero(dn, sizeof (dnode_t)); 54 55 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 56 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 57 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 58 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 59 60 refcount_create(&dn->dn_holds); 61 refcount_create(&dn->dn_tx_holds); 62 63 for (i = 0; i < TXG_SIZE; i++) { 64 avl_create(&dn->dn_ranges[i], free_range_compar, 65 sizeof (free_range_t), 66 offsetof(struct free_range, fr_node)); 67 list_create(&dn->dn_dirty_records[i], 68 sizeof (dbuf_dirty_record_t), 69 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 70 } 71 72 list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), 73 offsetof(dmu_buf_impl_t, db_link)); 74 75 return (0); 76 } 77 78 /* ARGSUSED */ 79 static void 80 dnode_dest(void *arg, void *unused) 81 { 82 int i; 83 dnode_t *dn = arg; 84 85 rw_destroy(&dn->dn_struct_rwlock); 86 mutex_destroy(&dn->dn_mtx); 87 mutex_destroy(&dn->dn_dbufs_mtx); 88 cv_destroy(&dn->dn_notxholds); 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(DMU_OBJECT_IS_SPECIAL(dn->dn_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 /* Swap SPILL block if we have one */ 214 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 215 byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t)); 216 217 } 218 219 void 220 dnode_buf_byteswap(void *vbuf, size_t size) 221 { 222 dnode_phys_t *buf = vbuf; 223 int i; 224 225 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 226 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 227 228 size >>= DNODE_SHIFT; 229 for (i = 0; i < size; i++) { 230 dnode_byteswap(buf); 231 buf++; 232 } 233 } 234 235 static int 236 free_range_compar(const void *node1, const void *node2) 237 { 238 const free_range_t *rp1 = node1; 239 const free_range_t *rp2 = node2; 240 241 if (rp1->fr_blkid < rp2->fr_blkid) 242 return (-1); 243 else if (rp1->fr_blkid > rp2->fr_blkid) 244 return (1); 245 else return (0); 246 } 247 248 void 249 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 250 { 251 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 252 253 dnode_setdirty(dn, tx); 254 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 255 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 256 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 257 dn->dn_bonuslen = newsize; 258 if (newsize == 0) 259 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 260 else 261 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 262 rw_exit(&dn->dn_struct_rwlock); 263 } 264 265 void 266 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 267 { 268 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 269 dnode_setdirty(dn, tx); 270 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 271 dn->dn_bonustype = newtype; 272 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 273 rw_exit(&dn->dn_struct_rwlock); 274 } 275 276 void 277 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 278 { 279 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 280 ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); 281 dnode_setdirty(dn, tx); 282 dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; 283 dn->dn_have_spill = B_FALSE; 284 } 285 286 static void 287 dnode_setdblksz(dnode_t *dn, int size) 288 { 289 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 290 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 291 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 292 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 293 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 294 dn->dn_datablksz = size; 295 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 296 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 297 } 298 299 static dnode_t * 300 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 301 uint64_t object) 302 { 303 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 304 (void) dnode_cons(dn, NULL, 0); /* XXX */ 305 306 dn->dn_objset = os; 307 dn->dn_object = object; 308 dn->dn_dbuf = db; 309 dn->dn_phys = dnp; 310 311 if (dnp->dn_datablkszsec) 312 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 313 dn->dn_indblkshift = dnp->dn_indblkshift; 314 dn->dn_nlevels = dnp->dn_nlevels; 315 dn->dn_type = dnp->dn_type; 316 dn->dn_nblkptr = dnp->dn_nblkptr; 317 dn->dn_checksum = dnp->dn_checksum; 318 dn->dn_compress = dnp->dn_compress; 319 dn->dn_bonustype = dnp->dn_bonustype; 320 dn->dn_bonuslen = dnp->dn_bonuslen; 321 dn->dn_maxblkid = dnp->dn_maxblkid; 322 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 323 dn->dn_id_flags = 0; 324 325 dmu_zfetch_init(&dn->dn_zfetch, dn); 326 327 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 328 mutex_enter(&os->os_lock); 329 list_insert_head(&os->os_dnodes, dn); 330 mutex_exit(&os->os_lock); 331 332 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 333 return (dn); 334 } 335 336 static void 337 dnode_destroy(dnode_t *dn) 338 { 339 objset_t *os = dn->dn_objset; 340 341 #ifdef ZFS_DEBUG 342 int i; 343 344 for (i = 0; i < TXG_SIZE; i++) { 345 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 346 ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); 347 ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); 348 } 349 ASSERT(NULL == list_head(&dn->dn_dbufs)); 350 #endif 351 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 352 353 mutex_enter(&os->os_lock); 354 list_remove(&os->os_dnodes, dn); 355 mutex_exit(&os->os_lock); 356 357 if (dn->dn_dirtyctx_firstset) { 358 kmem_free(dn->dn_dirtyctx_firstset, 1); 359 dn->dn_dirtyctx_firstset = NULL; 360 } 361 dmu_zfetch_rele(&dn->dn_zfetch); 362 if (dn->dn_bonus) { 363 mutex_enter(&dn->dn_bonus->db_mtx); 364 dbuf_evict(dn->dn_bonus); 365 dn->dn_bonus = NULL; 366 } 367 kmem_cache_free(dnode_cache, dn); 368 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 369 } 370 371 void 372 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 373 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 374 { 375 int i; 376 377 if (blocksize == 0) 378 blocksize = 1 << zfs_default_bs; 379 else if (blocksize > SPA_MAXBLOCKSIZE) 380 blocksize = SPA_MAXBLOCKSIZE; 381 else 382 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 383 384 if (ibs == 0) 385 ibs = zfs_default_ibs; 386 387 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 388 389 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 390 dn->dn_object, tx->tx_txg, blocksize, ibs); 391 392 ASSERT(dn->dn_type == DMU_OT_NONE); 393 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 394 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 395 ASSERT(ot != DMU_OT_NONE); 396 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 397 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 398 (bonustype == DMU_OT_SA && bonuslen == 0) || 399 (bonustype != DMU_OT_NONE && bonuslen != 0)); 400 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 401 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 402 ASSERT(dn->dn_type == DMU_OT_NONE); 403 ASSERT3U(dn->dn_maxblkid, ==, 0); 404 ASSERT3U(dn->dn_allocated_txg, ==, 0); 405 ASSERT3U(dn->dn_assigned_txg, ==, 0); 406 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 407 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 408 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 409 410 for (i = 0; i < TXG_SIZE; i++) { 411 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 412 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 413 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 414 ASSERT3U(dn->dn_next_bonustype[i], ==, 0); 415 ASSERT3U(dn->dn_rm_spillblk[i], ==, 0); 416 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 417 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 418 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 419 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 420 } 421 422 dn->dn_type = ot; 423 dnode_setdblksz(dn, blocksize); 424 dn->dn_indblkshift = ibs; 425 dn->dn_nlevels = 1; 426 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 427 dn->dn_nblkptr = 1; 428 else 429 dn->dn_nblkptr = 1 + 430 ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 431 dn->dn_bonustype = bonustype; 432 dn->dn_bonuslen = bonuslen; 433 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 434 dn->dn_compress = ZIO_COMPRESS_INHERIT; 435 dn->dn_dirtyctx = 0; 436 437 dn->dn_free_txg = 0; 438 if (dn->dn_dirtyctx_firstset) { 439 kmem_free(dn->dn_dirtyctx_firstset, 1); 440 dn->dn_dirtyctx_firstset = NULL; 441 } 442 443 dn->dn_allocated_txg = tx->tx_txg; 444 dn->dn_id_flags = 0; 445 446 dnode_setdirty(dn, tx); 447 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 448 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 449 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 450 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 451 } 452 453 void 454 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 455 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 456 { 457 int nblkptr; 458 459 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 460 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 461 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 462 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 463 ASSERT(tx->tx_txg != 0); 464 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 465 (bonustype != DMU_OT_NONE && bonuslen != 0) || 466 (bonustype == DMU_OT_SA && bonuslen == 0)); 467 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 468 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 469 470 /* clean up any unreferenced dbufs */ 471 dnode_evict_dbufs(dn); 472 473 dn->dn_id_flags = 0; 474 475 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 476 dnode_setdirty(dn, tx); 477 if (dn->dn_datablksz != blocksize) { 478 /* change blocksize */ 479 ASSERT(dn->dn_maxblkid == 0 && 480 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 481 dnode_block_freed(dn, 0))); 482 dnode_setdblksz(dn, blocksize); 483 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 484 } 485 if (dn->dn_bonuslen != bonuslen) 486 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 487 488 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 489 nblkptr = 1; 490 else 491 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 492 if (dn->dn_bonustype != bonustype) 493 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 494 if (dn->dn_nblkptr != nblkptr) 495 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 496 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 497 dbuf_rm_spill(dn, tx); 498 dnode_rm_spill(dn, tx); 499 } 500 rw_exit(&dn->dn_struct_rwlock); 501 502 /* change type */ 503 dn->dn_type = ot; 504 505 /* change bonus size and type */ 506 mutex_enter(&dn->dn_mtx); 507 dn->dn_bonustype = bonustype; 508 dn->dn_bonuslen = bonuslen; 509 dn->dn_nblkptr = nblkptr; 510 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 511 dn->dn_compress = ZIO_COMPRESS_INHERIT; 512 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 513 514 /* fix up the bonus db_size */ 515 if (dn->dn_bonus) { 516 dn->dn_bonus->db.db_size = 517 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 518 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 519 } 520 521 dn->dn_allocated_txg = tx->tx_txg; 522 mutex_exit(&dn->dn_mtx); 523 } 524 525 void 526 dnode_special_close(dnode_t *dn) 527 { 528 /* 529 * Wait for final references to the dnode to clear. This can 530 * only happen if the arc is asyncronously evicting state that 531 * has a hold on this dnode while we are trying to evict this 532 * dnode. 533 */ 534 while (refcount_count(&dn->dn_holds) > 0) 535 delay(1); 536 dnode_destroy(dn); 537 } 538 539 dnode_t * 540 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object) 541 { 542 dnode_t *dn = dnode_create(os, dnp, NULL, object); 543 DNODE_VERIFY(dn); 544 return (dn); 545 } 546 547 static void 548 dnode_buf_pageout(dmu_buf_t *db, void *arg) 549 { 550 dnode_t **children_dnodes = arg; 551 int i; 552 int epb = db->db_size >> DNODE_SHIFT; 553 554 for (i = 0; i < epb; i++) { 555 dnode_t *dn = children_dnodes[i]; 556 int n; 557 558 if (dn == NULL) 559 continue; 560 #ifdef ZFS_DEBUG 561 /* 562 * If there are holds on this dnode, then there should 563 * be holds on the dnode's containing dbuf as well; thus 564 * it wouldn't be eligable for eviction and this function 565 * would not have been called. 566 */ 567 ASSERT(refcount_is_zero(&dn->dn_holds)); 568 ASSERT(list_head(&dn->dn_dbufs) == NULL); 569 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 570 571 for (n = 0; n < TXG_SIZE; n++) 572 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 573 #endif 574 children_dnodes[i] = NULL; 575 dnode_destroy(dn); 576 } 577 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 578 } 579 580 /* 581 * errors: 582 * EINVAL - invalid object number. 583 * EIO - i/o error. 584 * succeeds even for free dnodes. 585 */ 586 int 587 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 588 void *tag, dnode_t **dnp) 589 { 590 int epb, idx, err; 591 int drop_struct_lock = FALSE; 592 int type; 593 uint64_t blk; 594 dnode_t *mdn, *dn; 595 dmu_buf_impl_t *db; 596 dnode_t **children_dnodes; 597 598 /* 599 * If you are holding the spa config lock as writer, you shouldn't 600 * be asking the DMU to do *anything* unless it's the root pool 601 * which may require us to read from the root filesystem while 602 * holding some (not all) of the locks as writer. 603 */ 604 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 605 (spa_is_root(os->os_spa) && 606 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER) && 607 !spa_config_held(os->os_spa, SCL_ZIO, RW_WRITER))); 608 609 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 610 dn = (object == DMU_USERUSED_OBJECT) ? 611 os->os_userused_dnode : os->os_groupused_dnode; 612 if (dn == NULL) 613 return (ENOENT); 614 type = dn->dn_type; 615 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 616 return (ENOENT); 617 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 618 return (EEXIST); 619 DNODE_VERIFY(dn); 620 (void) refcount_add(&dn->dn_holds, tag); 621 *dnp = dn; 622 return (0); 623 } 624 625 if (object == 0 || object >= DN_MAX_OBJECT) 626 return (EINVAL); 627 628 mdn = os->os_meta_dnode; 629 630 DNODE_VERIFY(mdn); 631 632 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 633 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 634 drop_struct_lock = TRUE; 635 } 636 637 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 638 639 db = dbuf_hold(mdn, blk, FTAG); 640 if (drop_struct_lock) 641 rw_exit(&mdn->dn_struct_rwlock); 642 if (db == NULL) 643 return (EIO); 644 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 645 if (err) { 646 dbuf_rele(db, FTAG); 647 return (err); 648 } 649 650 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 651 epb = db->db.db_size >> DNODE_SHIFT; 652 653 idx = object & (epb-1); 654 655 children_dnodes = dmu_buf_get_user(&db->db); 656 if (children_dnodes == NULL) { 657 dnode_t **winner; 658 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 659 KM_SLEEP); 660 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 661 dnode_buf_pageout)) { 662 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 663 children_dnodes = winner; 664 } 665 } 666 667 if ((dn = children_dnodes[idx]) == NULL) { 668 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 669 dnode_t *winner; 670 671 dn = dnode_create(os, dnp, db, object); 672 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 673 if (winner != NULL) { 674 dnode_destroy(dn); 675 dn = winner; 676 } 677 } 678 679 mutex_enter(&dn->dn_mtx); 680 type = dn->dn_type; 681 if (dn->dn_free_txg || 682 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 683 ((flag & DNODE_MUST_BE_FREE) && 684 (type != DMU_OT_NONE || !refcount_is_zero(&dn->dn_holds)))) { 685 mutex_exit(&dn->dn_mtx); 686 dbuf_rele(db, FTAG); 687 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 688 } 689 mutex_exit(&dn->dn_mtx); 690 691 if (refcount_add(&dn->dn_holds, tag) == 1) 692 dbuf_add_ref(db, dn); 693 694 DNODE_VERIFY(dn); 695 ASSERT3P(dn->dn_dbuf, ==, db); 696 ASSERT3U(dn->dn_object, ==, object); 697 dbuf_rele(db, FTAG); 698 699 *dnp = dn; 700 return (0); 701 } 702 703 /* 704 * Return held dnode if the object is allocated, NULL if not. 705 */ 706 int 707 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 708 { 709 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 710 } 711 712 /* 713 * Can only add a reference if there is already at least one 714 * reference on the dnode. Returns FALSE if unable to add a 715 * new reference. 716 */ 717 boolean_t 718 dnode_add_ref(dnode_t *dn, void *tag) 719 { 720 mutex_enter(&dn->dn_mtx); 721 if (refcount_is_zero(&dn->dn_holds)) { 722 mutex_exit(&dn->dn_mtx); 723 return (FALSE); 724 } 725 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 726 mutex_exit(&dn->dn_mtx); 727 return (TRUE); 728 } 729 730 void 731 dnode_rele(dnode_t *dn, void *tag) 732 { 733 uint64_t refs; 734 735 mutex_enter(&dn->dn_mtx); 736 refs = refcount_remove(&dn->dn_holds, tag); 737 mutex_exit(&dn->dn_mtx); 738 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 739 if (refs == 0 && dn->dn_dbuf) 740 dbuf_rele(dn->dn_dbuf, dn); 741 } 742 743 void 744 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 745 { 746 objset_t *os = dn->dn_objset; 747 uint64_t txg = tx->tx_txg; 748 749 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 750 dsl_dataset_dirty(os->os_dsl_dataset, tx); 751 return; 752 } 753 754 DNODE_VERIFY(dn); 755 756 #ifdef ZFS_DEBUG 757 mutex_enter(&dn->dn_mtx); 758 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 759 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 760 mutex_exit(&dn->dn_mtx); 761 #endif 762 763 /* 764 * Determine old uid/gid when necessary 765 */ 766 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 767 768 mutex_enter(&os->os_lock); 769 770 /* 771 * If we are already marked dirty, we're done. 772 */ 773 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 774 mutex_exit(&os->os_lock); 775 return; 776 } 777 778 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 779 ASSERT(dn->dn_datablksz != 0); 780 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 781 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 782 ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0); 783 784 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 785 dn->dn_object, txg); 786 787 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 788 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 789 } else { 790 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 791 } 792 793 mutex_exit(&os->os_lock); 794 795 /* 796 * The dnode maintains a hold on its containing dbuf as 797 * long as there are holds on it. Each instantiated child 798 * dbuf maintaines a hold on the dnode. When the last child 799 * drops its hold, the dnode will drop its hold on the 800 * containing dbuf. We add a "dirty hold" here so that the 801 * dnode will hang around after we finish processing its 802 * children. 803 */ 804 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 805 806 (void) dbuf_dirty(dn->dn_dbuf, tx); 807 808 dsl_dataset_dirty(os->os_dsl_dataset, tx); 809 } 810 811 void 812 dnode_free(dnode_t *dn, dmu_tx_t *tx) 813 { 814 int txgoff = tx->tx_txg & TXG_MASK; 815 816 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 817 818 /* we should be the only holder... hopefully */ 819 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 820 821 mutex_enter(&dn->dn_mtx); 822 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 823 mutex_exit(&dn->dn_mtx); 824 return; 825 } 826 dn->dn_free_txg = tx->tx_txg; 827 mutex_exit(&dn->dn_mtx); 828 829 /* 830 * If the dnode is already dirty, it needs to be moved from 831 * the dirty list to the free list. 832 */ 833 mutex_enter(&dn->dn_objset->os_lock); 834 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 835 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 836 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 837 mutex_exit(&dn->dn_objset->os_lock); 838 } else { 839 mutex_exit(&dn->dn_objset->os_lock); 840 dnode_setdirty(dn, tx); 841 } 842 } 843 844 /* 845 * Try to change the block size for the indicated dnode. This can only 846 * succeed if there are no blocks allocated or dirty beyond first block 847 */ 848 int 849 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 850 { 851 dmu_buf_impl_t *db, *db_next; 852 int err; 853 854 if (size == 0) 855 size = SPA_MINBLOCKSIZE; 856 if (size > SPA_MAXBLOCKSIZE) 857 size = SPA_MAXBLOCKSIZE; 858 else 859 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 860 861 if (ibs == dn->dn_indblkshift) 862 ibs = 0; 863 864 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 865 return (0); 866 867 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 868 869 /* Check for any allocated blocks beyond the first */ 870 if (dn->dn_phys->dn_maxblkid != 0) 871 goto fail; 872 873 mutex_enter(&dn->dn_dbufs_mtx); 874 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 875 db_next = list_next(&dn->dn_dbufs, db); 876 877 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 878 db->db_blkid != DMU_SPILL_BLKID) { 879 mutex_exit(&dn->dn_dbufs_mtx); 880 goto fail; 881 } 882 } 883 mutex_exit(&dn->dn_dbufs_mtx); 884 885 if (ibs && dn->dn_nlevels != 1) 886 goto fail; 887 888 /* resize the old block */ 889 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 890 if (err == 0) 891 dbuf_new_size(db, size, tx); 892 else if (err != ENOENT) 893 goto fail; 894 895 dnode_setdblksz(dn, size); 896 dnode_setdirty(dn, tx); 897 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 898 if (ibs) { 899 dn->dn_indblkshift = ibs; 900 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 901 } 902 /* rele after we have fixed the blocksize in the dnode */ 903 if (db) 904 dbuf_rele(db, FTAG); 905 906 rw_exit(&dn->dn_struct_rwlock); 907 return (0); 908 909 fail: 910 rw_exit(&dn->dn_struct_rwlock); 911 return (ENOTSUP); 912 } 913 914 /* read-holding callers must not rely on the lock being continuously held */ 915 void 916 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 917 { 918 uint64_t txgoff = tx->tx_txg & TXG_MASK; 919 int epbs, new_nlevels; 920 uint64_t sz; 921 922 ASSERT(blkid != DMU_BONUS_BLKID); 923 924 ASSERT(have_read ? 925 RW_READ_HELD(&dn->dn_struct_rwlock) : 926 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 927 928 /* 929 * if we have a read-lock, check to see if we need to do any work 930 * before upgrading to a write-lock. 931 */ 932 if (have_read) { 933 if (blkid <= dn->dn_maxblkid) 934 return; 935 936 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 937 rw_exit(&dn->dn_struct_rwlock); 938 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 939 } 940 } 941 942 if (blkid <= dn->dn_maxblkid) 943 goto out; 944 945 dn->dn_maxblkid = blkid; 946 947 /* 948 * Compute the number of levels necessary to support the new maxblkid. 949 */ 950 new_nlevels = 1; 951 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 952 for (sz = dn->dn_nblkptr; 953 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 954 new_nlevels++; 955 956 if (new_nlevels > dn->dn_nlevels) { 957 int old_nlevels = dn->dn_nlevels; 958 dmu_buf_impl_t *db; 959 list_t *list; 960 dbuf_dirty_record_t *new, *dr, *dr_next; 961 962 dn->dn_nlevels = new_nlevels; 963 964 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 965 dn->dn_next_nlevels[txgoff] = new_nlevels; 966 967 /* dirty the left indirects */ 968 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 969 ASSERT(db != NULL); 970 new = dbuf_dirty(db, tx); 971 dbuf_rele(db, FTAG); 972 973 /* transfer the dirty records to the new indirect */ 974 mutex_enter(&dn->dn_mtx); 975 mutex_enter(&new->dt.di.dr_mtx); 976 list = &dn->dn_dirty_records[txgoff]; 977 for (dr = list_head(list); dr; dr = dr_next) { 978 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 979 if (dr->dr_dbuf->db_level != new_nlevels-1 && 980 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 981 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 982 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 983 list_remove(&dn->dn_dirty_records[txgoff], dr); 984 list_insert_tail(&new->dt.di.dr_children, dr); 985 dr->dr_parent = new; 986 } 987 } 988 mutex_exit(&new->dt.di.dr_mtx); 989 mutex_exit(&dn->dn_mtx); 990 } 991 992 out: 993 if (have_read) 994 rw_downgrade(&dn->dn_struct_rwlock); 995 } 996 997 void 998 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 999 { 1000 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1001 avl_index_t where; 1002 free_range_t *rp; 1003 free_range_t rp_tofind; 1004 uint64_t endblk = blkid + nblks; 1005 1006 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 1007 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 1008 1009 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1010 blkid, nblks, tx->tx_txg); 1011 rp_tofind.fr_blkid = blkid; 1012 rp = avl_find(tree, &rp_tofind, &where); 1013 if (rp == NULL) 1014 rp = avl_nearest(tree, where, AVL_BEFORE); 1015 if (rp == NULL) 1016 rp = avl_nearest(tree, where, AVL_AFTER); 1017 1018 while (rp && (rp->fr_blkid <= blkid + nblks)) { 1019 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 1020 free_range_t *nrp = AVL_NEXT(tree, rp); 1021 1022 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 1023 /* clear this entire range */ 1024 avl_remove(tree, rp); 1025 kmem_free(rp, sizeof (free_range_t)); 1026 } else if (blkid <= rp->fr_blkid && 1027 endblk > rp->fr_blkid && endblk < fr_endblk) { 1028 /* clear the beginning of this range */ 1029 rp->fr_blkid = endblk; 1030 rp->fr_nblks = fr_endblk - endblk; 1031 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 1032 endblk >= fr_endblk) { 1033 /* clear the end of this range */ 1034 rp->fr_nblks = blkid - rp->fr_blkid; 1035 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 1036 /* clear a chunk out of this range */ 1037 free_range_t *new_rp = 1038 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1039 1040 new_rp->fr_blkid = endblk; 1041 new_rp->fr_nblks = fr_endblk - endblk; 1042 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 1043 rp->fr_nblks = blkid - rp->fr_blkid; 1044 } 1045 /* there may be no overlap */ 1046 rp = nrp; 1047 } 1048 } 1049 1050 void 1051 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1052 { 1053 dmu_buf_impl_t *db; 1054 uint64_t blkoff, blkid, nblks; 1055 int blksz, blkshift, head, tail; 1056 int trunc = FALSE; 1057 int epbs; 1058 1059 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1060 blksz = dn->dn_datablksz; 1061 blkshift = dn->dn_datablkshift; 1062 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1063 1064 if (len == -1ULL) { 1065 len = UINT64_MAX - off; 1066 trunc = TRUE; 1067 } 1068 1069 /* 1070 * First, block align the region to free: 1071 */ 1072 if (ISP2(blksz)) { 1073 head = P2NPHASE(off, blksz); 1074 blkoff = P2PHASE(off, blksz); 1075 if ((off >> blkshift) > dn->dn_maxblkid) 1076 goto out; 1077 } else { 1078 ASSERT(dn->dn_maxblkid == 0); 1079 if (off == 0 && len >= blksz) { 1080 /* Freeing the whole block; fast-track this request */ 1081 blkid = 0; 1082 nblks = 1; 1083 goto done; 1084 } else if (off >= blksz) { 1085 /* Freeing past end-of-data */ 1086 goto out; 1087 } else { 1088 /* Freeing part of the block. */ 1089 head = blksz - off; 1090 ASSERT3U(head, >, 0); 1091 } 1092 blkoff = off; 1093 } 1094 /* zero out any partial block data at the start of the range */ 1095 if (head) { 1096 ASSERT3U(blkoff + head, ==, blksz); 1097 if (len < head) 1098 head = len; 1099 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1100 FTAG, &db) == 0) { 1101 caddr_t data; 1102 1103 /* don't dirty if it isn't on disk and isn't dirty */ 1104 if (db->db_last_dirty || 1105 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1106 rw_exit(&dn->dn_struct_rwlock); 1107 dbuf_will_dirty(db, tx); 1108 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1109 data = db->db.db_data; 1110 bzero(data + blkoff, head); 1111 } 1112 dbuf_rele(db, FTAG); 1113 } 1114 off += head; 1115 len -= head; 1116 } 1117 1118 /* If the range was less than one block, we're done */ 1119 if (len == 0) 1120 goto out; 1121 1122 /* If the remaining range is past end of file, we're done */ 1123 if ((off >> blkshift) > dn->dn_maxblkid) 1124 goto out; 1125 1126 ASSERT(ISP2(blksz)); 1127 if (trunc) 1128 tail = 0; 1129 else 1130 tail = P2PHASE(len, blksz); 1131 1132 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1133 /* zero out any partial block data at the end of the range */ 1134 if (tail) { 1135 if (len < tail) 1136 tail = len; 1137 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1138 TRUE, FTAG, &db) == 0) { 1139 /* don't dirty if not on disk and not dirty */ 1140 if (db->db_last_dirty || 1141 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1142 rw_exit(&dn->dn_struct_rwlock); 1143 dbuf_will_dirty(db, tx); 1144 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1145 bzero(db->db.db_data, tail); 1146 } 1147 dbuf_rele(db, FTAG); 1148 } 1149 len -= tail; 1150 } 1151 1152 /* If the range did not include a full block, we are done */ 1153 if (len == 0) 1154 goto out; 1155 1156 ASSERT(IS_P2ALIGNED(off, blksz)); 1157 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1158 blkid = off >> blkshift; 1159 nblks = len >> blkshift; 1160 if (trunc) 1161 nblks += 1; 1162 1163 /* 1164 * Read in and mark all the level-1 indirects dirty, 1165 * so that they will stay in memory until syncing phase. 1166 * Always dirty the first and last indirect to make sure 1167 * we dirty all the partial indirects. 1168 */ 1169 if (dn->dn_nlevels > 1) { 1170 uint64_t i, first, last; 1171 int shift = epbs + dn->dn_datablkshift; 1172 1173 first = blkid >> epbs; 1174 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1175 dbuf_will_dirty(db, tx); 1176 dbuf_rele(db, FTAG); 1177 } 1178 if (trunc) 1179 last = dn->dn_maxblkid >> epbs; 1180 else 1181 last = (blkid + nblks - 1) >> epbs; 1182 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1183 dbuf_will_dirty(db, tx); 1184 dbuf_rele(db, FTAG); 1185 } 1186 for (i = first + 1; i < last; i++) { 1187 uint64_t ibyte = i << shift; 1188 int err; 1189 1190 err = dnode_next_offset(dn, 1191 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1192 i = ibyte >> shift; 1193 if (err == ESRCH || i >= last) 1194 break; 1195 ASSERT(err == 0); 1196 db = dbuf_hold_level(dn, 1, i, FTAG); 1197 if (db) { 1198 dbuf_will_dirty(db, tx); 1199 dbuf_rele(db, FTAG); 1200 } 1201 } 1202 } 1203 done: 1204 /* 1205 * Add this range to the dnode range list. 1206 * We will finish up this free operation in the syncing phase. 1207 */ 1208 mutex_enter(&dn->dn_mtx); 1209 dnode_clear_range(dn, blkid, nblks, tx); 1210 { 1211 free_range_t *rp, *found; 1212 avl_index_t where; 1213 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1214 1215 /* Add new range to dn_ranges */ 1216 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1217 rp->fr_blkid = blkid; 1218 rp->fr_nblks = nblks; 1219 found = avl_find(tree, rp, &where); 1220 ASSERT(found == NULL); 1221 avl_insert(tree, rp, where); 1222 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1223 blkid, nblks, tx->tx_txg); 1224 } 1225 mutex_exit(&dn->dn_mtx); 1226 1227 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1228 dnode_setdirty(dn, tx); 1229 out: 1230 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1231 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1232 1233 rw_exit(&dn->dn_struct_rwlock); 1234 } 1235 1236 static boolean_t 1237 dnode_spill_freed(dnode_t *dn) 1238 { 1239 int i; 1240 1241 mutex_enter(&dn->dn_mtx); 1242 for (i = 0; i < TXG_SIZE; i++) { 1243 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1244 break; 1245 } 1246 mutex_exit(&dn->dn_mtx); 1247 return (i < TXG_SIZE); 1248 } 1249 1250 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1251 uint64_t 1252 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1253 { 1254 free_range_t range_tofind; 1255 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1256 int i; 1257 1258 if (blkid == DMU_BONUS_BLKID) 1259 return (FALSE); 1260 1261 /* 1262 * If we're in the process of opening the pool, dp will not be 1263 * set yet, but there shouldn't be anything dirty. 1264 */ 1265 if (dp == NULL) 1266 return (FALSE); 1267 1268 if (dn->dn_free_txg) 1269 return (TRUE); 1270 1271 if (blkid == DMU_SPILL_BLKID) 1272 return (dnode_spill_freed(dn)); 1273 1274 range_tofind.fr_blkid = blkid; 1275 mutex_enter(&dn->dn_mtx); 1276 for (i = 0; i < TXG_SIZE; i++) { 1277 free_range_t *range_found; 1278 avl_index_t idx; 1279 1280 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1281 if (range_found) { 1282 ASSERT(range_found->fr_nblks > 0); 1283 break; 1284 } 1285 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1286 if (range_found && 1287 range_found->fr_blkid + range_found->fr_nblks > blkid) 1288 break; 1289 } 1290 mutex_exit(&dn->dn_mtx); 1291 return (i < TXG_SIZE); 1292 } 1293 1294 /* call from syncing context when we actually write/free space for this dnode */ 1295 void 1296 dnode_diduse_space(dnode_t *dn, int64_t delta) 1297 { 1298 uint64_t space; 1299 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1300 dn, dn->dn_phys, 1301 (u_longlong_t)dn->dn_phys->dn_used, 1302 (longlong_t)delta); 1303 1304 mutex_enter(&dn->dn_mtx); 1305 space = DN_USED_BYTES(dn->dn_phys); 1306 if (delta > 0) { 1307 ASSERT3U(space + delta, >=, space); /* no overflow */ 1308 } else { 1309 ASSERT3U(space, >=, -delta); /* no underflow */ 1310 } 1311 space += delta; 1312 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1313 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1314 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1315 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1316 } else { 1317 dn->dn_phys->dn_used = space; 1318 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1319 } 1320 mutex_exit(&dn->dn_mtx); 1321 } 1322 1323 /* 1324 * Call when we think we're going to write/free space in open context. 1325 * Be conservative (ie. OK to write less than this or free more than 1326 * this, but don't write more or free less). 1327 */ 1328 void 1329 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1330 { 1331 objset_t *os = dn->dn_objset; 1332 dsl_dataset_t *ds = os->os_dsl_dataset; 1333 1334 if (space > 0) 1335 space = spa_get_asize(os->os_spa, space); 1336 1337 if (ds) 1338 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1339 1340 dmu_tx_willuse_space(tx, space); 1341 } 1342 1343 /* 1344 * This function scans a block at the indicated "level" looking for 1345 * a hole or data (depending on 'flags'). If level > 0, then we are 1346 * scanning an indirect block looking at its pointers. If level == 0, 1347 * then we are looking at a block of dnodes. If we don't find what we 1348 * are looking for in the block, we return ESRCH. Otherwise, return 1349 * with *offset pointing to the beginning (if searching forwards) or 1350 * end (if searching backwards) of the range covered by the block 1351 * pointer we matched on (or dnode). 1352 * 1353 * The basic search algorithm used below by dnode_next_offset() is to 1354 * use this function to search up the block tree (widen the search) until 1355 * we find something (i.e., we don't return ESRCH) and then search back 1356 * down the tree (narrow the search) until we reach our original search 1357 * level. 1358 */ 1359 static int 1360 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1361 int lvl, uint64_t blkfill, uint64_t txg) 1362 { 1363 dmu_buf_impl_t *db = NULL; 1364 void *data = NULL; 1365 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1366 uint64_t epb = 1ULL << epbs; 1367 uint64_t minfill, maxfill; 1368 boolean_t hole; 1369 int i, inc, error, span; 1370 1371 dprintf("probing object %llu offset %llx level %d of %u\n", 1372 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1373 1374 hole = ((flags & DNODE_FIND_HOLE) != 0); 1375 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1376 ASSERT(txg == 0 || !hole); 1377 1378 if (lvl == dn->dn_phys->dn_nlevels) { 1379 error = 0; 1380 epb = dn->dn_phys->dn_nblkptr; 1381 data = dn->dn_phys->dn_blkptr; 1382 } else { 1383 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1384 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1385 if (error) { 1386 if (error != ENOENT) 1387 return (error); 1388 if (hole) 1389 return (0); 1390 /* 1391 * This can only happen when we are searching up 1392 * the block tree for data. We don't really need to 1393 * adjust the offset, as we will just end up looking 1394 * at the pointer to this block in its parent, and its 1395 * going to be unallocated, so we will skip over it. 1396 */ 1397 return (ESRCH); 1398 } 1399 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1400 if (error) { 1401 dbuf_rele(db, FTAG); 1402 return (error); 1403 } 1404 data = db->db.db_data; 1405 } 1406 1407 if (db && txg && 1408 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1409 /* 1410 * This can only happen when we are searching up the tree 1411 * and these conditions mean that we need to keep climbing. 1412 */ 1413 error = ESRCH; 1414 } else if (lvl == 0) { 1415 dnode_phys_t *dnp = data; 1416 span = DNODE_SHIFT; 1417 ASSERT(dn->dn_type == DMU_OT_DNODE); 1418 1419 for (i = (*offset >> span) & (blkfill - 1); 1420 i >= 0 && i < blkfill; i += inc) { 1421 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1422 break; 1423 *offset += (1ULL << span) * inc; 1424 } 1425 if (i < 0 || i == blkfill) 1426 error = ESRCH; 1427 } else { 1428 blkptr_t *bp = data; 1429 uint64_t start = *offset; 1430 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1431 minfill = 0; 1432 maxfill = blkfill << ((lvl - 1) * epbs); 1433 1434 if (hole) 1435 maxfill--; 1436 else 1437 minfill++; 1438 1439 *offset = *offset >> span; 1440 for (i = BF64_GET(*offset, 0, epbs); 1441 i >= 0 && i < epb; i += inc) { 1442 if (bp[i].blk_fill >= minfill && 1443 bp[i].blk_fill <= maxfill && 1444 (hole || bp[i].blk_birth > txg)) 1445 break; 1446 if (inc > 0 || *offset > 0) 1447 *offset += inc; 1448 } 1449 *offset = *offset << span; 1450 if (inc < 0) { 1451 /* traversing backwards; position offset at the end */ 1452 ASSERT3U(*offset, <=, start); 1453 *offset = MIN(*offset + (1ULL << span) - 1, start); 1454 } else if (*offset < start) { 1455 *offset = start; 1456 } 1457 if (i < 0 || i >= epb) 1458 error = ESRCH; 1459 } 1460 1461 if (db) 1462 dbuf_rele(db, FTAG); 1463 1464 return (error); 1465 } 1466 1467 /* 1468 * Find the next hole, data, or sparse region at or after *offset. 1469 * The value 'blkfill' tells us how many items we expect to find 1470 * in an L0 data block; this value is 1 for normal objects, 1471 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1472 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1473 * 1474 * Examples: 1475 * 1476 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1477 * Finds the next/previous hole/data in a file. 1478 * Used in dmu_offset_next(). 1479 * 1480 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1481 * Finds the next free/allocated dnode an objset's meta-dnode. 1482 * Only finds objects that have new contents since txg (ie. 1483 * bonus buffer changes and content removal are ignored). 1484 * Used in dmu_object_next(). 1485 * 1486 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1487 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1488 * Used in dmu_object_alloc(). 1489 */ 1490 int 1491 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1492 int minlvl, uint64_t blkfill, uint64_t txg) 1493 { 1494 uint64_t initial_offset = *offset; 1495 int lvl, maxlvl; 1496 int error = 0; 1497 1498 if (!(flags & DNODE_FIND_HAVELOCK)) 1499 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1500 1501 if (dn->dn_phys->dn_nlevels == 0) { 1502 error = ESRCH; 1503 goto out; 1504 } 1505 1506 if (dn->dn_datablkshift == 0) { 1507 if (*offset < dn->dn_datablksz) { 1508 if (flags & DNODE_FIND_HOLE) 1509 *offset = dn->dn_datablksz; 1510 } else { 1511 error = ESRCH; 1512 } 1513 goto out; 1514 } 1515 1516 maxlvl = dn->dn_phys->dn_nlevels; 1517 1518 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1519 error = dnode_next_offset_level(dn, 1520 flags, offset, lvl, blkfill, txg); 1521 if (error != ESRCH) 1522 break; 1523 } 1524 1525 while (error == 0 && --lvl >= minlvl) { 1526 error = dnode_next_offset_level(dn, 1527 flags, offset, lvl, blkfill, txg); 1528 } 1529 1530 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1531 initial_offset < *offset : initial_offset > *offset)) 1532 error = ESRCH; 1533 out: 1534 if (!(flags & DNODE_FIND_HAVELOCK)) 1535 rw_exit(&dn->dn_struct_rwlock); 1536 1537 return (error); 1538 } 1539