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 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 474 dnode_setdirty(dn, tx); 475 if (dn->dn_datablksz != blocksize) { 476 /* change blocksize */ 477 ASSERT(dn->dn_maxblkid == 0 && 478 (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || 479 dnode_block_freed(dn, 0))); 480 dnode_setdblksz(dn, blocksize); 481 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; 482 } 483 if (dn->dn_bonuslen != bonuslen) 484 dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; 485 486 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 487 nblkptr = 1; 488 else 489 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 490 if (dn->dn_bonustype != bonustype) 491 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 492 if (dn->dn_nblkptr != nblkptr) 493 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 494 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 495 dbuf_rm_spill(dn, tx); 496 dnode_rm_spill(dn, tx); 497 } 498 rw_exit(&dn->dn_struct_rwlock); 499 500 /* change type */ 501 dn->dn_type = ot; 502 503 /* change bonus size and type */ 504 mutex_enter(&dn->dn_mtx); 505 dn->dn_bonustype = bonustype; 506 dn->dn_bonuslen = bonuslen; 507 dn->dn_nblkptr = nblkptr; 508 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 509 dn->dn_compress = ZIO_COMPRESS_INHERIT; 510 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 511 512 /* fix up the bonus db_size */ 513 if (dn->dn_bonus) { 514 dn->dn_bonus->db.db_size = 515 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 516 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 517 } 518 519 dn->dn_allocated_txg = tx->tx_txg; 520 mutex_exit(&dn->dn_mtx); 521 } 522 523 void 524 dnode_special_close(dnode_t *dn) 525 { 526 /* 527 * Wait for final references to the dnode to clear. This can 528 * only happen if the arc is asyncronously evicting state that 529 * has a hold on this dnode while we are trying to evict this 530 * dnode. 531 */ 532 while (refcount_count(&dn->dn_holds) > 0) 533 delay(1); 534 dnode_destroy(dn); 535 } 536 537 dnode_t * 538 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object) 539 { 540 dnode_t *dn = dnode_create(os, dnp, NULL, object); 541 DNODE_VERIFY(dn); 542 return (dn); 543 } 544 545 static void 546 dnode_buf_pageout(dmu_buf_t *db, void *arg) 547 { 548 dnode_t **children_dnodes = arg; 549 int i; 550 int epb = db->db_size >> DNODE_SHIFT; 551 552 for (i = 0; i < epb; i++) { 553 dnode_t *dn = children_dnodes[i]; 554 int n; 555 556 if (dn == NULL) 557 continue; 558 #ifdef ZFS_DEBUG 559 /* 560 * If there are holds on this dnode, then there should 561 * be holds on the dnode's containing dbuf as well; thus 562 * it wouldn't be eligable for eviction and this function 563 * would not have been called. 564 */ 565 ASSERT(refcount_is_zero(&dn->dn_holds)); 566 ASSERT(list_head(&dn->dn_dbufs) == NULL); 567 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 568 569 for (n = 0; n < TXG_SIZE; n++) 570 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 571 #endif 572 children_dnodes[i] = NULL; 573 dnode_destroy(dn); 574 } 575 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 576 } 577 578 /* 579 * errors: 580 * EINVAL - invalid object number. 581 * EIO - i/o error. 582 * succeeds even for free dnodes. 583 */ 584 int 585 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 586 void *tag, dnode_t **dnp) 587 { 588 int epb, idx, err; 589 int drop_struct_lock = FALSE; 590 int type; 591 uint64_t blk; 592 dnode_t *mdn, *dn; 593 dmu_buf_impl_t *db; 594 dnode_t **children_dnodes; 595 596 /* 597 * If you are holding the spa config lock as writer, you shouldn't 598 * be asking the DMU to do *anything* unless it's the root pool 599 * which may require us to read from the root filesystem while 600 * holding some (not all) of the locks as writer. 601 */ 602 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 603 (spa_is_root(os->os_spa) && 604 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER) && 605 !spa_config_held(os->os_spa, SCL_ZIO, RW_WRITER))); 606 607 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 608 dn = (object == DMU_USERUSED_OBJECT) ? 609 os->os_userused_dnode : os->os_groupused_dnode; 610 if (dn == NULL) 611 return (ENOENT); 612 type = dn->dn_type; 613 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 614 return (ENOENT); 615 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 616 return (EEXIST); 617 DNODE_VERIFY(dn); 618 (void) refcount_add(&dn->dn_holds, tag); 619 *dnp = dn; 620 return (0); 621 } 622 623 if (object == 0 || object >= DN_MAX_OBJECT) 624 return (EINVAL); 625 626 mdn = os->os_meta_dnode; 627 628 DNODE_VERIFY(mdn); 629 630 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 631 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 632 drop_struct_lock = TRUE; 633 } 634 635 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 636 637 db = dbuf_hold(mdn, blk, FTAG); 638 if (drop_struct_lock) 639 rw_exit(&mdn->dn_struct_rwlock); 640 if (db == NULL) 641 return (EIO); 642 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 643 if (err) { 644 dbuf_rele(db, FTAG); 645 return (err); 646 } 647 648 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 649 epb = db->db.db_size >> DNODE_SHIFT; 650 651 idx = object & (epb-1); 652 653 children_dnodes = dmu_buf_get_user(&db->db); 654 if (children_dnodes == NULL) { 655 dnode_t **winner; 656 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 657 KM_SLEEP); 658 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 659 dnode_buf_pageout)) { 660 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 661 children_dnodes = winner; 662 } 663 } 664 665 if ((dn = children_dnodes[idx]) == NULL) { 666 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 667 dnode_t *winner; 668 669 dn = dnode_create(os, dnp, db, object); 670 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 671 if (winner != NULL) { 672 dnode_destroy(dn); 673 dn = winner; 674 } 675 } 676 677 mutex_enter(&dn->dn_mtx); 678 type = dn->dn_type; 679 if (dn->dn_free_txg || 680 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 681 ((flag & DNODE_MUST_BE_FREE) && 682 (type != DMU_OT_NONE || (dn->dn_id_flags & DN_ID_SYNC)))) { 683 mutex_exit(&dn->dn_mtx); 684 dbuf_rele(db, FTAG); 685 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 686 } 687 if (flag & DNODE_MUST_BE_FREE) { 688 ASSERT(refcount_is_zero(&dn->dn_holds)); 689 ASSERT(!(dn->dn_id_flags & DN_ID_SYNC)); 690 } 691 mutex_exit(&dn->dn_mtx); 692 693 if (refcount_add(&dn->dn_holds, tag) == 1) 694 dbuf_add_ref(db, dn); 695 696 DNODE_VERIFY(dn); 697 ASSERT3P(dn->dn_dbuf, ==, db); 698 ASSERT3U(dn->dn_object, ==, object); 699 dbuf_rele(db, FTAG); 700 701 *dnp = dn; 702 return (0); 703 } 704 705 /* 706 * Return held dnode if the object is allocated, NULL if not. 707 */ 708 int 709 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 710 { 711 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 712 } 713 714 /* 715 * Can only add a reference if there is already at least one 716 * reference on the dnode. Returns FALSE if unable to add a 717 * new reference. 718 */ 719 boolean_t 720 dnode_add_ref(dnode_t *dn, void *tag) 721 { 722 mutex_enter(&dn->dn_mtx); 723 if (refcount_is_zero(&dn->dn_holds)) { 724 mutex_exit(&dn->dn_mtx); 725 return (FALSE); 726 } 727 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 728 mutex_exit(&dn->dn_mtx); 729 return (TRUE); 730 } 731 732 void 733 dnode_rele(dnode_t *dn, void *tag) 734 { 735 uint64_t refs; 736 737 mutex_enter(&dn->dn_mtx); 738 refs = refcount_remove(&dn->dn_holds, tag); 739 mutex_exit(&dn->dn_mtx); 740 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 741 if (refs == 0 && dn->dn_dbuf) 742 dbuf_rele(dn->dn_dbuf, dn); 743 } 744 745 void 746 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 747 { 748 objset_t *os = dn->dn_objset; 749 uint64_t txg = tx->tx_txg; 750 751 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 752 dsl_dataset_dirty(os->os_dsl_dataset, tx); 753 return; 754 } 755 756 DNODE_VERIFY(dn); 757 758 #ifdef ZFS_DEBUG 759 mutex_enter(&dn->dn_mtx); 760 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 761 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 762 mutex_exit(&dn->dn_mtx); 763 #endif 764 765 /* 766 * Determine old uid/gid when necessary 767 */ 768 dmu_objset_userquota_get_ids(dn, B_TRUE, tx); 769 770 mutex_enter(&os->os_lock); 771 772 /* 773 * If we are already marked dirty, we're done. 774 */ 775 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 776 mutex_exit(&os->os_lock); 777 return; 778 } 779 780 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 781 ASSERT(dn->dn_datablksz != 0); 782 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 783 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 784 ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0); 785 786 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 787 dn->dn_object, txg); 788 789 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 790 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 791 } else { 792 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 793 } 794 795 mutex_exit(&os->os_lock); 796 797 /* 798 * The dnode maintains a hold on its containing dbuf as 799 * long as there are holds on it. Each instantiated child 800 * dbuf maintaines a hold on the dnode. When the last child 801 * drops its hold, the dnode will drop its hold on the 802 * containing dbuf. We add a "dirty hold" here so that the 803 * dnode will hang around after we finish processing its 804 * children. 805 */ 806 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 807 808 (void) dbuf_dirty(dn->dn_dbuf, tx); 809 810 dsl_dataset_dirty(os->os_dsl_dataset, tx); 811 } 812 813 void 814 dnode_free(dnode_t *dn, dmu_tx_t *tx) 815 { 816 int txgoff = tx->tx_txg & TXG_MASK; 817 818 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 819 820 /* we should be the only holder... hopefully */ 821 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 822 823 mutex_enter(&dn->dn_mtx); 824 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 825 mutex_exit(&dn->dn_mtx); 826 return; 827 } 828 dn->dn_free_txg = tx->tx_txg; 829 mutex_exit(&dn->dn_mtx); 830 831 /* 832 * If the dnode is already dirty, it needs to be moved from 833 * the dirty list to the free list. 834 */ 835 mutex_enter(&dn->dn_objset->os_lock); 836 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 837 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 838 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 839 mutex_exit(&dn->dn_objset->os_lock); 840 } else { 841 mutex_exit(&dn->dn_objset->os_lock); 842 dnode_setdirty(dn, tx); 843 } 844 } 845 846 /* 847 * Try to change the block size for the indicated dnode. This can only 848 * succeed if there are no blocks allocated or dirty beyond first block 849 */ 850 int 851 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 852 { 853 dmu_buf_impl_t *db, *db_next; 854 int err; 855 856 if (size == 0) 857 size = SPA_MINBLOCKSIZE; 858 if (size > SPA_MAXBLOCKSIZE) 859 size = SPA_MAXBLOCKSIZE; 860 else 861 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 862 863 if (ibs == dn->dn_indblkshift) 864 ibs = 0; 865 866 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 867 return (0); 868 869 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 870 871 /* Check for any allocated blocks beyond the first */ 872 if (dn->dn_phys->dn_maxblkid != 0) 873 goto fail; 874 875 mutex_enter(&dn->dn_dbufs_mtx); 876 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 877 db_next = list_next(&dn->dn_dbufs, db); 878 879 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 880 db->db_blkid != DMU_SPILL_BLKID) { 881 mutex_exit(&dn->dn_dbufs_mtx); 882 goto fail; 883 } 884 } 885 mutex_exit(&dn->dn_dbufs_mtx); 886 887 if (ibs && dn->dn_nlevels != 1) 888 goto fail; 889 890 /* resize the old block */ 891 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 892 if (err == 0) 893 dbuf_new_size(db, size, tx); 894 else if (err != ENOENT) 895 goto fail; 896 897 dnode_setdblksz(dn, size); 898 dnode_setdirty(dn, tx); 899 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 900 if (ibs) { 901 dn->dn_indblkshift = ibs; 902 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 903 } 904 /* rele after we have fixed the blocksize in the dnode */ 905 if (db) 906 dbuf_rele(db, FTAG); 907 908 rw_exit(&dn->dn_struct_rwlock); 909 return (0); 910 911 fail: 912 rw_exit(&dn->dn_struct_rwlock); 913 return (ENOTSUP); 914 } 915 916 /* read-holding callers must not rely on the lock being continuously held */ 917 void 918 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 919 { 920 uint64_t txgoff = tx->tx_txg & TXG_MASK; 921 int epbs, new_nlevels; 922 uint64_t sz; 923 924 ASSERT(blkid != DMU_BONUS_BLKID); 925 926 ASSERT(have_read ? 927 RW_READ_HELD(&dn->dn_struct_rwlock) : 928 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 929 930 /* 931 * if we have a read-lock, check to see if we need to do any work 932 * before upgrading to a write-lock. 933 */ 934 if (have_read) { 935 if (blkid <= dn->dn_maxblkid) 936 return; 937 938 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 939 rw_exit(&dn->dn_struct_rwlock); 940 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 941 } 942 } 943 944 if (blkid <= dn->dn_maxblkid) 945 goto out; 946 947 dn->dn_maxblkid = blkid; 948 949 /* 950 * Compute the number of levels necessary to support the new maxblkid. 951 */ 952 new_nlevels = 1; 953 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 954 for (sz = dn->dn_nblkptr; 955 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 956 new_nlevels++; 957 958 if (new_nlevels > dn->dn_nlevels) { 959 int old_nlevels = dn->dn_nlevels; 960 dmu_buf_impl_t *db; 961 list_t *list; 962 dbuf_dirty_record_t *new, *dr, *dr_next; 963 964 dn->dn_nlevels = new_nlevels; 965 966 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 967 dn->dn_next_nlevels[txgoff] = new_nlevels; 968 969 /* dirty the left indirects */ 970 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 971 ASSERT(db != NULL); 972 new = dbuf_dirty(db, tx); 973 dbuf_rele(db, FTAG); 974 975 /* transfer the dirty records to the new indirect */ 976 mutex_enter(&dn->dn_mtx); 977 mutex_enter(&new->dt.di.dr_mtx); 978 list = &dn->dn_dirty_records[txgoff]; 979 for (dr = list_head(list); dr; dr = dr_next) { 980 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 981 if (dr->dr_dbuf->db_level != new_nlevels-1 && 982 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 983 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 984 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 985 list_remove(&dn->dn_dirty_records[txgoff], dr); 986 list_insert_tail(&new->dt.di.dr_children, dr); 987 dr->dr_parent = new; 988 } 989 } 990 mutex_exit(&new->dt.di.dr_mtx); 991 mutex_exit(&dn->dn_mtx); 992 } 993 994 out: 995 if (have_read) 996 rw_downgrade(&dn->dn_struct_rwlock); 997 } 998 999 void 1000 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 1001 { 1002 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1003 avl_index_t where; 1004 free_range_t *rp; 1005 free_range_t rp_tofind; 1006 uint64_t endblk = blkid + nblks; 1007 1008 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 1009 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 1010 1011 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1012 blkid, nblks, tx->tx_txg); 1013 rp_tofind.fr_blkid = blkid; 1014 rp = avl_find(tree, &rp_tofind, &where); 1015 if (rp == NULL) 1016 rp = avl_nearest(tree, where, AVL_BEFORE); 1017 if (rp == NULL) 1018 rp = avl_nearest(tree, where, AVL_AFTER); 1019 1020 while (rp && (rp->fr_blkid <= blkid + nblks)) { 1021 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 1022 free_range_t *nrp = AVL_NEXT(tree, rp); 1023 1024 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 1025 /* clear this entire range */ 1026 avl_remove(tree, rp); 1027 kmem_free(rp, sizeof (free_range_t)); 1028 } else if (blkid <= rp->fr_blkid && 1029 endblk > rp->fr_blkid && endblk < fr_endblk) { 1030 /* clear the beginning of this range */ 1031 rp->fr_blkid = endblk; 1032 rp->fr_nblks = fr_endblk - endblk; 1033 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 1034 endblk >= fr_endblk) { 1035 /* clear the end of this range */ 1036 rp->fr_nblks = blkid - rp->fr_blkid; 1037 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 1038 /* clear a chunk out of this range */ 1039 free_range_t *new_rp = 1040 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1041 1042 new_rp->fr_blkid = endblk; 1043 new_rp->fr_nblks = fr_endblk - endblk; 1044 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 1045 rp->fr_nblks = blkid - rp->fr_blkid; 1046 } 1047 /* there may be no overlap */ 1048 rp = nrp; 1049 } 1050 } 1051 1052 void 1053 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1054 { 1055 dmu_buf_impl_t *db; 1056 uint64_t blkoff, blkid, nblks; 1057 int blksz, blkshift, head, tail; 1058 int trunc = FALSE; 1059 int epbs; 1060 1061 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1062 blksz = dn->dn_datablksz; 1063 blkshift = dn->dn_datablkshift; 1064 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1065 1066 if (len == -1ULL) { 1067 len = UINT64_MAX - off; 1068 trunc = TRUE; 1069 } 1070 1071 /* 1072 * First, block align the region to free: 1073 */ 1074 if (ISP2(blksz)) { 1075 head = P2NPHASE(off, blksz); 1076 blkoff = P2PHASE(off, blksz); 1077 if ((off >> blkshift) > dn->dn_maxblkid) 1078 goto out; 1079 } else { 1080 ASSERT(dn->dn_maxblkid == 0); 1081 if (off == 0 && len >= blksz) { 1082 /* Freeing the whole block; fast-track this request */ 1083 blkid = 0; 1084 nblks = 1; 1085 goto done; 1086 } else if (off >= blksz) { 1087 /* Freeing past end-of-data */ 1088 goto out; 1089 } else { 1090 /* Freeing part of the block. */ 1091 head = blksz - off; 1092 ASSERT3U(head, >, 0); 1093 } 1094 blkoff = off; 1095 } 1096 /* zero out any partial block data at the start of the range */ 1097 if (head) { 1098 ASSERT3U(blkoff + head, ==, blksz); 1099 if (len < head) 1100 head = len; 1101 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1102 FTAG, &db) == 0) { 1103 caddr_t data; 1104 1105 /* don't dirty if it isn't on disk and isn't dirty */ 1106 if (db->db_last_dirty || 1107 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1108 rw_exit(&dn->dn_struct_rwlock); 1109 dbuf_will_dirty(db, tx); 1110 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1111 data = db->db.db_data; 1112 bzero(data + blkoff, head); 1113 } 1114 dbuf_rele(db, FTAG); 1115 } 1116 off += head; 1117 len -= head; 1118 } 1119 1120 /* If the range was less than one block, we're done */ 1121 if (len == 0) 1122 goto out; 1123 1124 /* If the remaining range is past end of file, we're done */ 1125 if ((off >> blkshift) > dn->dn_maxblkid) 1126 goto out; 1127 1128 ASSERT(ISP2(blksz)); 1129 if (trunc) 1130 tail = 0; 1131 else 1132 tail = P2PHASE(len, blksz); 1133 1134 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1135 /* zero out any partial block data at the end of the range */ 1136 if (tail) { 1137 if (len < tail) 1138 tail = len; 1139 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1140 TRUE, FTAG, &db) == 0) { 1141 /* don't dirty if not on disk and not dirty */ 1142 if (db->db_last_dirty || 1143 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1144 rw_exit(&dn->dn_struct_rwlock); 1145 dbuf_will_dirty(db, tx); 1146 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1147 bzero(db->db.db_data, tail); 1148 } 1149 dbuf_rele(db, FTAG); 1150 } 1151 len -= tail; 1152 } 1153 1154 /* If the range did not include a full block, we are done */ 1155 if (len == 0) 1156 goto out; 1157 1158 ASSERT(IS_P2ALIGNED(off, blksz)); 1159 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1160 blkid = off >> blkshift; 1161 nblks = len >> blkshift; 1162 if (trunc) 1163 nblks += 1; 1164 1165 /* 1166 * Read in and mark all the level-1 indirects dirty, 1167 * so that they will stay in memory until syncing phase. 1168 * Always dirty the first and last indirect to make sure 1169 * we dirty all the partial indirects. 1170 */ 1171 if (dn->dn_nlevels > 1) { 1172 uint64_t i, first, last; 1173 int shift = epbs + dn->dn_datablkshift; 1174 1175 first = blkid >> epbs; 1176 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1177 dbuf_will_dirty(db, tx); 1178 dbuf_rele(db, FTAG); 1179 } 1180 if (trunc) 1181 last = dn->dn_maxblkid >> epbs; 1182 else 1183 last = (blkid + nblks - 1) >> epbs; 1184 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1185 dbuf_will_dirty(db, tx); 1186 dbuf_rele(db, FTAG); 1187 } 1188 for (i = first + 1; i < last; i++) { 1189 uint64_t ibyte = i << shift; 1190 int err; 1191 1192 err = dnode_next_offset(dn, 1193 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1194 i = ibyte >> shift; 1195 if (err == ESRCH || i >= last) 1196 break; 1197 ASSERT(err == 0); 1198 db = dbuf_hold_level(dn, 1, i, FTAG); 1199 if (db) { 1200 dbuf_will_dirty(db, tx); 1201 dbuf_rele(db, FTAG); 1202 } 1203 } 1204 } 1205 done: 1206 /* 1207 * Add this range to the dnode range list. 1208 * We will finish up this free operation in the syncing phase. 1209 */ 1210 mutex_enter(&dn->dn_mtx); 1211 dnode_clear_range(dn, blkid, nblks, tx); 1212 { 1213 free_range_t *rp, *found; 1214 avl_index_t where; 1215 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1216 1217 /* Add new range to dn_ranges */ 1218 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1219 rp->fr_blkid = blkid; 1220 rp->fr_nblks = nblks; 1221 found = avl_find(tree, rp, &where); 1222 ASSERT(found == NULL); 1223 avl_insert(tree, rp, where); 1224 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1225 blkid, nblks, tx->tx_txg); 1226 } 1227 mutex_exit(&dn->dn_mtx); 1228 1229 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1230 dnode_setdirty(dn, tx); 1231 out: 1232 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1233 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1234 1235 rw_exit(&dn->dn_struct_rwlock); 1236 } 1237 1238 static boolean_t 1239 dnode_spill_freed(dnode_t *dn) 1240 { 1241 int i; 1242 1243 mutex_enter(&dn->dn_mtx); 1244 for (i = 0; i < TXG_SIZE; i++) { 1245 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1246 break; 1247 } 1248 mutex_exit(&dn->dn_mtx); 1249 return (i < TXG_SIZE); 1250 } 1251 1252 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1253 uint64_t 1254 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1255 { 1256 free_range_t range_tofind; 1257 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1258 int i; 1259 1260 if (blkid == DMU_BONUS_BLKID) 1261 return (FALSE); 1262 1263 /* 1264 * If we're in the process of opening the pool, dp will not be 1265 * set yet, but there shouldn't be anything dirty. 1266 */ 1267 if (dp == NULL) 1268 return (FALSE); 1269 1270 if (dn->dn_free_txg) 1271 return (TRUE); 1272 1273 if (blkid == DMU_SPILL_BLKID) 1274 return (dnode_spill_freed(dn)); 1275 1276 range_tofind.fr_blkid = blkid; 1277 mutex_enter(&dn->dn_mtx); 1278 for (i = 0; i < TXG_SIZE; i++) { 1279 free_range_t *range_found; 1280 avl_index_t idx; 1281 1282 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1283 if (range_found) { 1284 ASSERT(range_found->fr_nblks > 0); 1285 break; 1286 } 1287 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1288 if (range_found && 1289 range_found->fr_blkid + range_found->fr_nblks > blkid) 1290 break; 1291 } 1292 mutex_exit(&dn->dn_mtx); 1293 return (i < TXG_SIZE); 1294 } 1295 1296 /* call from syncing context when we actually write/free space for this dnode */ 1297 void 1298 dnode_diduse_space(dnode_t *dn, int64_t delta) 1299 { 1300 uint64_t space; 1301 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1302 dn, dn->dn_phys, 1303 (u_longlong_t)dn->dn_phys->dn_used, 1304 (longlong_t)delta); 1305 1306 mutex_enter(&dn->dn_mtx); 1307 space = DN_USED_BYTES(dn->dn_phys); 1308 if (delta > 0) { 1309 ASSERT3U(space + delta, >=, space); /* no overflow */ 1310 } else { 1311 ASSERT3U(space, >=, -delta); /* no underflow */ 1312 } 1313 space += delta; 1314 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1315 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1316 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1317 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1318 } else { 1319 dn->dn_phys->dn_used = space; 1320 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1321 } 1322 mutex_exit(&dn->dn_mtx); 1323 } 1324 1325 /* 1326 * Call when we think we're going to write/free space in open context. 1327 * Be conservative (ie. OK to write less than this or free more than 1328 * this, but don't write more or free less). 1329 */ 1330 void 1331 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1332 { 1333 objset_t *os = dn->dn_objset; 1334 dsl_dataset_t *ds = os->os_dsl_dataset; 1335 1336 if (space > 0) 1337 space = spa_get_asize(os->os_spa, space); 1338 1339 if (ds) 1340 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1341 1342 dmu_tx_willuse_space(tx, space); 1343 } 1344 1345 /* 1346 * This function scans a block at the indicated "level" looking for 1347 * a hole or data (depending on 'flags'). If level > 0, then we are 1348 * scanning an indirect block looking at its pointers. If level == 0, 1349 * then we are looking at a block of dnodes. If we don't find what we 1350 * are looking for in the block, we return ESRCH. Otherwise, return 1351 * with *offset pointing to the beginning (if searching forwards) or 1352 * end (if searching backwards) of the range covered by the block 1353 * pointer we matched on (or dnode). 1354 * 1355 * The basic search algorithm used below by dnode_next_offset() is to 1356 * use this function to search up the block tree (widen the search) until 1357 * we find something (i.e., we don't return ESRCH) and then search back 1358 * down the tree (narrow the search) until we reach our original search 1359 * level. 1360 */ 1361 static int 1362 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1363 int lvl, uint64_t blkfill, uint64_t txg) 1364 { 1365 dmu_buf_impl_t *db = NULL; 1366 void *data = NULL; 1367 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1368 uint64_t epb = 1ULL << epbs; 1369 uint64_t minfill, maxfill; 1370 boolean_t hole; 1371 int i, inc, error, span; 1372 1373 dprintf("probing object %llu offset %llx level %d of %u\n", 1374 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1375 1376 hole = ((flags & DNODE_FIND_HOLE) != 0); 1377 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1378 ASSERT(txg == 0 || !hole); 1379 1380 if (lvl == dn->dn_phys->dn_nlevels) { 1381 error = 0; 1382 epb = dn->dn_phys->dn_nblkptr; 1383 data = dn->dn_phys->dn_blkptr; 1384 } else { 1385 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1386 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1387 if (error) { 1388 if (error != ENOENT) 1389 return (error); 1390 if (hole) 1391 return (0); 1392 /* 1393 * This can only happen when we are searching up 1394 * the block tree for data. We don't really need to 1395 * adjust the offset, as we will just end up looking 1396 * at the pointer to this block in its parent, and its 1397 * going to be unallocated, so we will skip over it. 1398 */ 1399 return (ESRCH); 1400 } 1401 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1402 if (error) { 1403 dbuf_rele(db, FTAG); 1404 return (error); 1405 } 1406 data = db->db.db_data; 1407 } 1408 1409 if (db && txg && 1410 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1411 /* 1412 * This can only happen when we are searching up the tree 1413 * and these conditions mean that we need to keep climbing. 1414 */ 1415 error = ESRCH; 1416 } else if (lvl == 0) { 1417 dnode_phys_t *dnp = data; 1418 span = DNODE_SHIFT; 1419 ASSERT(dn->dn_type == DMU_OT_DNODE); 1420 1421 for (i = (*offset >> span) & (blkfill - 1); 1422 i >= 0 && i < blkfill; i += inc) { 1423 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1424 break; 1425 *offset += (1ULL << span) * inc; 1426 } 1427 if (i < 0 || i == blkfill) 1428 error = ESRCH; 1429 } else { 1430 blkptr_t *bp = data; 1431 uint64_t start = *offset; 1432 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1433 minfill = 0; 1434 maxfill = blkfill << ((lvl - 1) * epbs); 1435 1436 if (hole) 1437 maxfill--; 1438 else 1439 minfill++; 1440 1441 *offset = *offset >> span; 1442 for (i = BF64_GET(*offset, 0, epbs); 1443 i >= 0 && i < epb; i += inc) { 1444 if (bp[i].blk_fill >= minfill && 1445 bp[i].blk_fill <= maxfill && 1446 (hole || bp[i].blk_birth > txg)) 1447 break; 1448 if (inc > 0 || *offset > 0) 1449 *offset += inc; 1450 } 1451 *offset = *offset << span; 1452 if (inc < 0) { 1453 /* traversing backwards; position offset at the end */ 1454 ASSERT3U(*offset, <=, start); 1455 *offset = MIN(*offset + (1ULL << span) - 1, start); 1456 } else if (*offset < start) { 1457 *offset = start; 1458 } 1459 if (i < 0 || i >= epb) 1460 error = ESRCH; 1461 } 1462 1463 if (db) 1464 dbuf_rele(db, FTAG); 1465 1466 return (error); 1467 } 1468 1469 /* 1470 * Find the next hole, data, or sparse region at or after *offset. 1471 * The value 'blkfill' tells us how many items we expect to find 1472 * in an L0 data block; this value is 1 for normal objects, 1473 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1474 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1475 * 1476 * Examples: 1477 * 1478 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1479 * Finds the next/previous hole/data in a file. 1480 * Used in dmu_offset_next(). 1481 * 1482 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1483 * Finds the next free/allocated dnode an objset's meta-dnode. 1484 * Only finds objects that have new contents since txg (ie. 1485 * bonus buffer changes and content removal are ignored). 1486 * Used in dmu_object_next(). 1487 * 1488 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1489 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1490 * Used in dmu_object_alloc(). 1491 */ 1492 int 1493 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1494 int minlvl, uint64_t blkfill, uint64_t txg) 1495 { 1496 uint64_t initial_offset = *offset; 1497 int lvl, maxlvl; 1498 int error = 0; 1499 1500 if (!(flags & DNODE_FIND_HAVELOCK)) 1501 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1502 1503 if (dn->dn_phys->dn_nlevels == 0) { 1504 error = ESRCH; 1505 goto out; 1506 } 1507 1508 if (dn->dn_datablkshift == 0) { 1509 if (*offset < dn->dn_datablksz) { 1510 if (flags & DNODE_FIND_HOLE) 1511 *offset = dn->dn_datablksz; 1512 } else { 1513 error = ESRCH; 1514 } 1515 goto out; 1516 } 1517 1518 maxlvl = dn->dn_phys->dn_nlevels; 1519 1520 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1521 error = dnode_next_offset_level(dn, 1522 flags, offset, lvl, blkfill, txg); 1523 if (error != ESRCH) 1524 break; 1525 } 1526 1527 while (error == 0 && --lvl >= minlvl) { 1528 error = dnode_next_offset_level(dn, 1529 flags, offset, lvl, blkfill, txg); 1530 } 1531 1532 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1533 initial_offset < *offset : initial_offset > *offset)) 1534 error = ESRCH; 1535 out: 1536 if (!(flags & DNODE_FIND_HAVELOCK)) 1537 rw_exit(&dn->dn_struct_rwlock); 1538 1539 return (error); 1540 } 1541