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 2010 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/dbuf.h> 28 #include <sys/dnode.h> 29 #include <sys/dmu.h> 30 #include <sys/dmu_impl.h> 31 #include <sys/dmu_tx.h> 32 #include <sys/dmu_objset.h> 33 #include <sys/dsl_dir.h> 34 #include <sys/dsl_dataset.h> 35 #include <sys/spa.h> 36 #include <sys/zio.h> 37 #include <sys/dmu_zfetch.h> 38 39 static int free_range_compar(const void *node1, const void *node2); 40 41 static kmem_cache_t *dnode_cache; 42 43 static dnode_phys_t dnode_phys_zero; 44 45 int zfs_default_bs = SPA_MINBLOCKSHIFT; 46 int zfs_default_ibs = DN_MAX_INDBLKSHIFT; 47 48 /* ARGSUSED */ 49 static int 50 dnode_cons(void *arg, void *unused, int kmflag) 51 { 52 int i; 53 dnode_t *dn = arg; 54 bzero(dn, sizeof (dnode_t)); 55 56 rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); 57 mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); 58 mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); 59 cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); 60 61 refcount_create(&dn->dn_holds); 62 refcount_create(&dn->dn_tx_holds); 63 64 for (i = 0; i < TXG_SIZE; i++) { 65 avl_create(&dn->dn_ranges[i], free_range_compar, 66 sizeof (free_range_t), 67 offsetof(struct free_range, fr_node)); 68 list_create(&dn->dn_dirty_records[i], 69 sizeof (dbuf_dirty_record_t), 70 offsetof(dbuf_dirty_record_t, dr_dirty_node)); 71 } 72 73 list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), 74 offsetof(dmu_buf_impl_t, db_link)); 75 76 return (0); 77 } 78 79 /* ARGSUSED */ 80 static void 81 dnode_dest(void *arg, void *unused) 82 { 83 int i; 84 dnode_t *dn = arg; 85 86 rw_destroy(&dn->dn_struct_rwlock); 87 mutex_destroy(&dn->dn_mtx); 88 mutex_destroy(&dn->dn_dbufs_mtx); 89 cv_destroy(&dn->dn_notxholds); 90 refcount_destroy(&dn->dn_holds); 91 refcount_destroy(&dn->dn_tx_holds); 92 93 for (i = 0; i < TXG_SIZE; i++) { 94 avl_destroy(&dn->dn_ranges[i]); 95 list_destroy(&dn->dn_dirty_records[i]); 96 } 97 98 list_destroy(&dn->dn_dbufs); 99 } 100 101 void 102 dnode_init(void) 103 { 104 dnode_cache = kmem_cache_create("dnode_t", 105 sizeof (dnode_t), 106 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); 107 } 108 109 void 110 dnode_fini(void) 111 { 112 kmem_cache_destroy(dnode_cache); 113 } 114 115 116 #ifdef ZFS_DEBUG 117 void 118 dnode_verify(dnode_t *dn) 119 { 120 int drop_struct_lock = FALSE; 121 122 ASSERT(dn->dn_phys); 123 ASSERT(dn->dn_objset); 124 125 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 126 127 if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) 128 return; 129 130 if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { 131 rw_enter(&dn->dn_struct_rwlock, RW_READER); 132 drop_struct_lock = TRUE; 133 } 134 if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { 135 int i; 136 ASSERT3U(dn->dn_indblkshift, >=, 0); 137 ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); 138 if (dn->dn_datablkshift) { 139 ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); 140 ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); 141 ASSERT3U(1<<dn->dn_datablkshift, ==, dn->dn_datablksz); 142 } 143 ASSERT3U(dn->dn_nlevels, <=, 30); 144 ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); 145 ASSERT3U(dn->dn_nblkptr, >=, 1); 146 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 147 ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 148 ASSERT3U(dn->dn_datablksz, ==, 149 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 150 ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); 151 ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + 152 dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); 153 for (i = 0; i < TXG_SIZE; i++) { 154 ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); 155 } 156 } 157 if (dn->dn_phys->dn_type != DMU_OT_NONE) 158 ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); 159 ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); 160 if (dn->dn_dbuf != NULL) { 161 ASSERT3P(dn->dn_phys, ==, 162 (dnode_phys_t *)dn->dn_dbuf->db.db_data + 163 (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); 164 } 165 if (drop_struct_lock) 166 rw_exit(&dn->dn_struct_rwlock); 167 } 168 #endif 169 170 void 171 dnode_byteswap(dnode_phys_t *dnp) 172 { 173 uint64_t *buf64 = (void*)&dnp->dn_blkptr; 174 int i; 175 176 if (dnp->dn_type == DMU_OT_NONE) { 177 bzero(dnp, sizeof (dnode_phys_t)); 178 return; 179 } 180 181 dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); 182 dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); 183 dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); 184 dnp->dn_used = BSWAP_64(dnp->dn_used); 185 186 /* 187 * dn_nblkptr is only one byte, so it's OK to read it in either 188 * byte order. We can't read dn_bouslen. 189 */ 190 ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); 191 ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); 192 for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) 193 buf64[i] = BSWAP_64(buf64[i]); 194 195 /* 196 * OK to check dn_bonuslen for zero, because it won't matter if 197 * we have the wrong byte order. This is necessary because the 198 * dnode dnode is smaller than a regular dnode. 199 */ 200 if (dnp->dn_bonuslen != 0) { 201 /* 202 * Note that the bonus length calculated here may be 203 * longer than the actual bonus buffer. This is because 204 * we always put the bonus buffer after the last block 205 * pointer (instead of packing it against the end of the 206 * dnode buffer). 207 */ 208 int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); 209 size_t len = DN_MAX_BONUSLEN - off; 210 ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); 211 dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); 212 } 213 214 /* Swap SPILL block if we have one */ 215 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) 216 byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t)); 217 218 } 219 220 void 221 dnode_buf_byteswap(void *vbuf, size_t size) 222 { 223 dnode_phys_t *buf = vbuf; 224 int i; 225 226 ASSERT3U(sizeof (dnode_phys_t), ==, (1<<DNODE_SHIFT)); 227 ASSERT((size & (sizeof (dnode_phys_t)-1)) == 0); 228 229 size >>= DNODE_SHIFT; 230 for (i = 0; i < size; i++) { 231 dnode_byteswap(buf); 232 buf++; 233 } 234 } 235 236 static int 237 free_range_compar(const void *node1, const void *node2) 238 { 239 const free_range_t *rp1 = node1; 240 const free_range_t *rp2 = node2; 241 242 if (rp1->fr_blkid < rp2->fr_blkid) 243 return (-1); 244 else if (rp1->fr_blkid > rp2->fr_blkid) 245 return (1); 246 else return (0); 247 } 248 249 void 250 dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) 251 { 252 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 253 254 dnode_setdirty(dn, tx); 255 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 256 ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - 257 (dn->dn_nblkptr-1) * sizeof (blkptr_t)); 258 dn->dn_bonuslen = newsize; 259 if (newsize == 0) 260 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; 261 else 262 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 263 rw_exit(&dn->dn_struct_rwlock); 264 } 265 266 void 267 dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) 268 { 269 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 270 dnode_setdirty(dn, tx); 271 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 272 dn->dn_bonustype = newtype; 273 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 274 rw_exit(&dn->dn_struct_rwlock); 275 } 276 277 void 278 dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) 279 { 280 ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); 281 dnode_setdirty(dn, tx); 282 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 283 dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; 284 dn->dn_have_spill = B_FALSE; 285 rw_exit(&dn->dn_struct_rwlock); 286 } 287 288 static void 289 dnode_setdblksz(dnode_t *dn, int size) 290 { 291 ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); 292 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 293 ASSERT3U(size, >=, SPA_MINBLOCKSIZE); 294 ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 295 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); 296 dn->dn_datablksz = size; 297 dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; 298 dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; 299 } 300 301 static dnode_t * 302 dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, 303 uint64_t object) 304 { 305 dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); 306 (void) dnode_cons(dn, NULL, 0); /* XXX */ 307 308 dn->dn_objset = os; 309 dn->dn_object = object; 310 dn->dn_dbuf = db; 311 dn->dn_phys = dnp; 312 313 if (dnp->dn_datablkszsec) 314 dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); 315 dn->dn_indblkshift = dnp->dn_indblkshift; 316 dn->dn_nlevels = dnp->dn_nlevels; 317 dn->dn_type = dnp->dn_type; 318 dn->dn_nblkptr = dnp->dn_nblkptr; 319 dn->dn_checksum = dnp->dn_checksum; 320 dn->dn_compress = dnp->dn_compress; 321 dn->dn_bonustype = dnp->dn_bonustype; 322 dn->dn_bonuslen = dnp->dn_bonuslen; 323 dn->dn_maxblkid = dnp->dn_maxblkid; 324 dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); 325 326 dmu_zfetch_init(&dn->dn_zfetch, dn); 327 328 ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); 329 mutex_enter(&os->os_lock); 330 list_insert_head(&os->os_dnodes, dn); 331 mutex_exit(&os->os_lock); 332 333 arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); 334 return (dn); 335 } 336 337 static void 338 dnode_destroy(dnode_t *dn) 339 { 340 objset_t *os = dn->dn_objset; 341 342 #ifdef ZFS_DEBUG 343 int i; 344 345 for (i = 0; i < TXG_SIZE; i++) { 346 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 347 ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); 348 ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); 349 } 350 ASSERT(NULL == list_head(&dn->dn_dbufs)); 351 #endif 352 ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); 353 354 mutex_enter(&os->os_lock); 355 list_remove(&os->os_dnodes, dn); 356 mutex_exit(&os->os_lock); 357 358 if (dn->dn_dirtyctx_firstset) { 359 kmem_free(dn->dn_dirtyctx_firstset, 1); 360 dn->dn_dirtyctx_firstset = NULL; 361 } 362 dmu_zfetch_rele(&dn->dn_zfetch); 363 if (dn->dn_bonus) { 364 mutex_enter(&dn->dn_bonus->db_mtx); 365 dbuf_evict(dn->dn_bonus); 366 dn->dn_bonus = NULL; 367 } 368 kmem_cache_free(dnode_cache, dn); 369 arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); 370 } 371 372 void 373 dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, 374 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 375 { 376 int i; 377 378 if (blocksize == 0) 379 blocksize = 1 << zfs_default_bs; 380 else if (blocksize > SPA_MAXBLOCKSIZE) 381 blocksize = SPA_MAXBLOCKSIZE; 382 else 383 blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); 384 385 if (ibs == 0) 386 ibs = zfs_default_ibs; 387 388 ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); 389 390 dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, 391 dn->dn_object, tx->tx_txg, blocksize, ibs); 392 393 ASSERT(dn->dn_type == DMU_OT_NONE); 394 ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); 395 ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); 396 ASSERT(ot != DMU_OT_NONE); 397 ASSERT3U(ot, <, DMU_OT_NUMTYPES); 398 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 399 (bonustype == DMU_OT_SA && bonuslen == 0) || 400 (bonustype != DMU_OT_NONE && bonuslen != 0)); 401 ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); 402 ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); 403 ASSERT(dn->dn_type == DMU_OT_NONE); 404 ASSERT3U(dn->dn_maxblkid, ==, 0); 405 ASSERT3U(dn->dn_allocated_txg, ==, 0); 406 ASSERT3U(dn->dn_assigned_txg, ==, 0); 407 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 408 ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); 409 ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); 410 411 for (i = 0; i < TXG_SIZE; i++) { 412 ASSERT3U(dn->dn_next_nlevels[i], ==, 0); 413 ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); 414 ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); 415 ASSERT3U(dn->dn_next_bonustype[i], ==, 0); 416 ASSERT3U(dn->dn_rm_spillblk[i], ==, 0); 417 ASSERT3U(dn->dn_next_blksz[i], ==, 0); 418 ASSERT(!list_link_active(&dn->dn_dirty_link[i])); 419 ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); 420 ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); 421 } 422 423 dn->dn_type = ot; 424 dnode_setdblksz(dn, blocksize); 425 dn->dn_indblkshift = ibs; 426 dn->dn_nlevels = 1; 427 if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ 428 dn->dn_nblkptr = 1; 429 else 430 dn->dn_nblkptr = 1 + 431 ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 432 dn->dn_bonustype = bonustype; 433 dn->dn_bonuslen = bonuslen; 434 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 435 dn->dn_compress = ZIO_COMPRESS_INHERIT; 436 dn->dn_dirtyctx = 0; 437 438 dn->dn_free_txg = 0; 439 if (dn->dn_dirtyctx_firstset) { 440 kmem_free(dn->dn_dirtyctx_firstset, 1); 441 dn->dn_dirtyctx_firstset = NULL; 442 } 443 444 dn->dn_allocated_txg = tx->tx_txg; 445 dn->dn_id_flags = 0; 446 447 dnode_setdirty(dn, tx); 448 dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; 449 dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; 450 dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; 451 dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; 452 } 453 454 void 455 dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, 456 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 457 { 458 int nblkptr; 459 460 ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); 461 ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); 462 ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); 463 ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); 464 ASSERT(tx->tx_txg != 0); 465 ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || 466 (bonustype != DMU_OT_NONE && 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 nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); 486 if (dn->dn_bonustype != bonustype) 487 dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; 488 if (dn->dn_nblkptr != nblkptr) 489 dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; 490 if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 491 dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; 492 dn->dn_have_spill = B_FALSE; 493 } 494 rw_exit(&dn->dn_struct_rwlock); 495 496 /* change type */ 497 dn->dn_type = ot; 498 499 /* change bonus size and type */ 500 mutex_enter(&dn->dn_mtx); 501 dn->dn_bonustype = bonustype; 502 dn->dn_bonuslen = bonuslen; 503 dn->dn_nblkptr = nblkptr; 504 dn->dn_checksum = ZIO_CHECKSUM_INHERIT; 505 dn->dn_compress = ZIO_COMPRESS_INHERIT; 506 ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); 507 508 /* fix up the bonus db_size */ 509 if (dn->dn_bonus) { 510 dn->dn_bonus->db.db_size = 511 DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); 512 ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); 513 } 514 515 dn->dn_allocated_txg = tx->tx_txg; 516 mutex_exit(&dn->dn_mtx); 517 } 518 519 void 520 dnode_special_close(dnode_t *dn) 521 { 522 /* 523 * Wait for final references to the dnode to clear. This can 524 * only happen if the arc is asyncronously evicting state that 525 * has a hold on this dnode while we are trying to evict this 526 * dnode. 527 */ 528 while (refcount_count(&dn->dn_holds) > 0) 529 delay(1); 530 dnode_destroy(dn); 531 } 532 533 dnode_t * 534 dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object) 535 { 536 dnode_t *dn = dnode_create(os, dnp, NULL, object); 537 DNODE_VERIFY(dn); 538 return (dn); 539 } 540 541 static void 542 dnode_buf_pageout(dmu_buf_t *db, void *arg) 543 { 544 dnode_t **children_dnodes = arg; 545 int i; 546 int epb = db->db_size >> DNODE_SHIFT; 547 548 for (i = 0; i < epb; i++) { 549 dnode_t *dn = children_dnodes[i]; 550 int n; 551 552 if (dn == NULL) 553 continue; 554 #ifdef ZFS_DEBUG 555 /* 556 * If there are holds on this dnode, then there should 557 * be holds on the dnode's containing dbuf as well; thus 558 * it wouldn't be eligable for eviction and this function 559 * would not have been called. 560 */ 561 ASSERT(refcount_is_zero(&dn->dn_holds)); 562 ASSERT(list_head(&dn->dn_dbufs) == NULL); 563 ASSERT(refcount_is_zero(&dn->dn_tx_holds)); 564 565 for (n = 0; n < TXG_SIZE; n++) 566 ASSERT(!list_link_active(&dn->dn_dirty_link[n])); 567 #endif 568 children_dnodes[i] = NULL; 569 dnode_destroy(dn); 570 } 571 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 572 } 573 574 /* 575 * errors: 576 * EINVAL - invalid object number. 577 * EIO - i/o error. 578 * succeeds even for free dnodes. 579 */ 580 int 581 dnode_hold_impl(objset_t *os, uint64_t object, int flag, 582 void *tag, dnode_t **dnp) 583 { 584 int epb, idx, err; 585 int drop_struct_lock = FALSE; 586 int type; 587 uint64_t blk; 588 dnode_t *mdn, *dn; 589 dmu_buf_impl_t *db; 590 dnode_t **children_dnodes; 591 592 /* 593 * If you are holding the spa config lock as writer, you shouldn't 594 * be asking the DMU to do *anything* unless it's the root pool 595 * which may require us to read from the root filesystem while 596 * holding some (not all) of the locks as writer. 597 */ 598 ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || 599 (spa_is_root(os->os_spa) && 600 spa_config_held(os->os_spa, SCL_STATE, RW_WRITER) && 601 !spa_config_held(os->os_spa, SCL_ZIO, RW_WRITER))); 602 603 if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { 604 dn = (object == DMU_USERUSED_OBJECT) ? 605 os->os_userused_dnode : os->os_groupused_dnode; 606 if (dn == NULL) 607 return (ENOENT); 608 type = dn->dn_type; 609 if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) 610 return (ENOENT); 611 if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) 612 return (EEXIST); 613 DNODE_VERIFY(dn); 614 (void) refcount_add(&dn->dn_holds, tag); 615 *dnp = dn; 616 return (0); 617 } 618 619 if (object == 0 || object >= DN_MAX_OBJECT) 620 return (EINVAL); 621 622 mdn = os->os_meta_dnode; 623 624 DNODE_VERIFY(mdn); 625 626 if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { 627 rw_enter(&mdn->dn_struct_rwlock, RW_READER); 628 drop_struct_lock = TRUE; 629 } 630 631 blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); 632 633 db = dbuf_hold(mdn, blk, FTAG); 634 if (drop_struct_lock) 635 rw_exit(&mdn->dn_struct_rwlock); 636 if (db == NULL) 637 return (EIO); 638 err = dbuf_read(db, NULL, DB_RF_CANFAIL); 639 if (err) { 640 dbuf_rele(db, FTAG); 641 return (err); 642 } 643 644 ASSERT3U(db->db.db_size, >=, 1<<DNODE_SHIFT); 645 epb = db->db.db_size >> DNODE_SHIFT; 646 647 idx = object & (epb-1); 648 649 children_dnodes = dmu_buf_get_user(&db->db); 650 if (children_dnodes == NULL) { 651 dnode_t **winner; 652 children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), 653 KM_SLEEP); 654 if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, 655 dnode_buf_pageout)) { 656 kmem_free(children_dnodes, epb * sizeof (dnode_t *)); 657 children_dnodes = winner; 658 } 659 } 660 661 if ((dn = children_dnodes[idx]) == NULL) { 662 dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; 663 dnode_t *winner; 664 665 dn = dnode_create(os, dnp, db, object); 666 winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); 667 if (winner != NULL) { 668 dnode_destroy(dn); 669 dn = winner; 670 } 671 } 672 673 mutex_enter(&dn->dn_mtx); 674 type = dn->dn_type; 675 if (dn->dn_free_txg || 676 ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || 677 ((flag & DNODE_MUST_BE_FREE) && 678 (type != DMU_OT_NONE || (dn->dn_id_flags & DN_ID_SYNC)))) { 679 mutex_exit(&dn->dn_mtx); 680 dbuf_rele(db, FTAG); 681 return (type == DMU_OT_NONE ? ENOENT : EEXIST); 682 } 683 if (flag & DNODE_MUST_BE_FREE) { 684 ASSERT(refcount_is_zero(&dn->dn_holds)); 685 ASSERT(!(dn->dn_id_flags & DN_ID_SYNC)); 686 } 687 mutex_exit(&dn->dn_mtx); 688 689 if (refcount_add(&dn->dn_holds, tag) == 1) 690 dbuf_add_ref(db, dn); 691 692 DNODE_VERIFY(dn); 693 ASSERT3P(dn->dn_dbuf, ==, db); 694 ASSERT3U(dn->dn_object, ==, object); 695 dbuf_rele(db, FTAG); 696 697 *dnp = dn; 698 return (0); 699 } 700 701 /* 702 * Return held dnode if the object is allocated, NULL if not. 703 */ 704 int 705 dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) 706 { 707 return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); 708 } 709 710 /* 711 * Can only add a reference if there is already at least one 712 * reference on the dnode. Returns FALSE if unable to add a 713 * new reference. 714 */ 715 boolean_t 716 dnode_add_ref(dnode_t *dn, void *tag) 717 { 718 mutex_enter(&dn->dn_mtx); 719 if (refcount_is_zero(&dn->dn_holds)) { 720 mutex_exit(&dn->dn_mtx); 721 return (FALSE); 722 } 723 VERIFY(1 < refcount_add(&dn->dn_holds, tag)); 724 mutex_exit(&dn->dn_mtx); 725 return (TRUE); 726 } 727 728 void 729 dnode_rele(dnode_t *dn, void *tag) 730 { 731 uint64_t refs; 732 733 mutex_enter(&dn->dn_mtx); 734 refs = refcount_remove(&dn->dn_holds, tag); 735 mutex_exit(&dn->dn_mtx); 736 /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ 737 if (refs == 0 && dn->dn_dbuf) 738 dbuf_rele(dn->dn_dbuf, dn); 739 } 740 741 void 742 dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) 743 { 744 objset_t *os = dn->dn_objset; 745 uint64_t txg = tx->tx_txg; 746 747 if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { 748 dsl_dataset_dirty(os->os_dsl_dataset, tx); 749 return; 750 } 751 752 DNODE_VERIFY(dn); 753 754 #ifdef ZFS_DEBUG 755 mutex_enter(&dn->dn_mtx); 756 ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); 757 /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ 758 mutex_exit(&dn->dn_mtx); 759 #endif 760 761 /* 762 * Determine old uid/gid when necessary 763 */ 764 dmu_objset_userquota_get_ids(dn, B_TRUE); 765 766 mutex_enter(&os->os_lock); 767 768 /* 769 * If we are already marked dirty, we're done. 770 */ 771 if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { 772 mutex_exit(&os->os_lock); 773 return; 774 } 775 776 ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); 777 ASSERT(dn->dn_datablksz != 0); 778 ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); 779 ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); 780 ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0); 781 782 dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", 783 dn->dn_object, txg); 784 785 if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { 786 list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); 787 } else { 788 list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); 789 } 790 791 mutex_exit(&os->os_lock); 792 793 /* 794 * The dnode maintains a hold on its containing dbuf as 795 * long as there are holds on it. Each instantiated child 796 * dbuf maintaines a hold on the dnode. When the last child 797 * drops its hold, the dnode will drop its hold on the 798 * containing dbuf. We add a "dirty hold" here so that the 799 * dnode will hang around after we finish processing its 800 * children. 801 */ 802 VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); 803 804 (void) dbuf_dirty(dn->dn_dbuf, tx); 805 806 dsl_dataset_dirty(os->os_dsl_dataset, tx); 807 } 808 809 void 810 dnode_free(dnode_t *dn, dmu_tx_t *tx) 811 { 812 int txgoff = tx->tx_txg & TXG_MASK; 813 814 dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); 815 816 /* we should be the only holder... hopefully */ 817 /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ 818 819 mutex_enter(&dn->dn_mtx); 820 if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { 821 mutex_exit(&dn->dn_mtx); 822 return; 823 } 824 dn->dn_free_txg = tx->tx_txg; 825 mutex_exit(&dn->dn_mtx); 826 827 /* 828 * If the dnode is already dirty, it needs to be moved from 829 * the dirty list to the free list. 830 */ 831 mutex_enter(&dn->dn_objset->os_lock); 832 if (list_link_active(&dn->dn_dirty_link[txgoff])) { 833 list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); 834 list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); 835 mutex_exit(&dn->dn_objset->os_lock); 836 } else { 837 mutex_exit(&dn->dn_objset->os_lock); 838 dnode_setdirty(dn, tx); 839 } 840 } 841 842 /* 843 * Try to change the block size for the indicated dnode. This can only 844 * succeed if there are no blocks allocated or dirty beyond first block 845 */ 846 int 847 dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) 848 { 849 dmu_buf_impl_t *db, *db_next; 850 int err; 851 852 if (size == 0) 853 size = SPA_MINBLOCKSIZE; 854 if (size > SPA_MAXBLOCKSIZE) 855 size = SPA_MAXBLOCKSIZE; 856 else 857 size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); 858 859 if (ibs == dn->dn_indblkshift) 860 ibs = 0; 861 862 if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) 863 return (0); 864 865 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 866 867 /* Check for any allocated blocks beyond the first */ 868 if (dn->dn_phys->dn_maxblkid != 0) 869 goto fail; 870 871 mutex_enter(&dn->dn_dbufs_mtx); 872 for (db = list_head(&dn->dn_dbufs); db; db = db_next) { 873 db_next = list_next(&dn->dn_dbufs, db); 874 875 if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && 876 db->db_blkid != DMU_SPILL_BLKID) { 877 mutex_exit(&dn->dn_dbufs_mtx); 878 goto fail; 879 } 880 } 881 mutex_exit(&dn->dn_dbufs_mtx); 882 883 if (ibs && dn->dn_nlevels != 1) 884 goto fail; 885 886 /* resize the old block */ 887 err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); 888 if (err == 0) 889 dbuf_new_size(db, size, tx); 890 else if (err != ENOENT) 891 goto fail; 892 893 dnode_setdblksz(dn, size); 894 dnode_setdirty(dn, tx); 895 dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; 896 if (ibs) { 897 dn->dn_indblkshift = ibs; 898 dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; 899 } 900 /* rele after we have fixed the blocksize in the dnode */ 901 if (db) 902 dbuf_rele(db, FTAG); 903 904 rw_exit(&dn->dn_struct_rwlock); 905 return (0); 906 907 fail: 908 rw_exit(&dn->dn_struct_rwlock); 909 return (ENOTSUP); 910 } 911 912 /* read-holding callers must not rely on the lock being continuously held */ 913 void 914 dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) 915 { 916 uint64_t txgoff = tx->tx_txg & TXG_MASK; 917 int epbs, new_nlevels; 918 uint64_t sz; 919 920 ASSERT(blkid != DMU_BONUS_BLKID); 921 922 ASSERT(have_read ? 923 RW_READ_HELD(&dn->dn_struct_rwlock) : 924 RW_WRITE_HELD(&dn->dn_struct_rwlock)); 925 926 /* 927 * if we have a read-lock, check to see if we need to do any work 928 * before upgrading to a write-lock. 929 */ 930 if (have_read) { 931 if (blkid <= dn->dn_maxblkid) 932 return; 933 934 if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { 935 rw_exit(&dn->dn_struct_rwlock); 936 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 937 } 938 } 939 940 if (blkid <= dn->dn_maxblkid) 941 goto out; 942 943 dn->dn_maxblkid = blkid; 944 945 /* 946 * Compute the number of levels necessary to support the new maxblkid. 947 */ 948 new_nlevels = 1; 949 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 950 for (sz = dn->dn_nblkptr; 951 sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) 952 new_nlevels++; 953 954 if (new_nlevels > dn->dn_nlevels) { 955 int old_nlevels = dn->dn_nlevels; 956 dmu_buf_impl_t *db; 957 list_t *list; 958 dbuf_dirty_record_t *new, *dr, *dr_next; 959 960 dn->dn_nlevels = new_nlevels; 961 962 ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); 963 dn->dn_next_nlevels[txgoff] = new_nlevels; 964 965 /* dirty the left indirects */ 966 db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); 967 new = dbuf_dirty(db, tx); 968 dbuf_rele(db, FTAG); 969 970 /* transfer the dirty records to the new indirect */ 971 mutex_enter(&dn->dn_mtx); 972 mutex_enter(&new->dt.di.dr_mtx); 973 list = &dn->dn_dirty_records[txgoff]; 974 for (dr = list_head(list); dr; dr = dr_next) { 975 dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); 976 if (dr->dr_dbuf->db_level != new_nlevels-1 && 977 dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && 978 dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { 979 ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); 980 list_remove(&dn->dn_dirty_records[txgoff], dr); 981 list_insert_tail(&new->dt.di.dr_children, dr); 982 dr->dr_parent = new; 983 } 984 } 985 mutex_exit(&new->dt.di.dr_mtx); 986 mutex_exit(&dn->dn_mtx); 987 } 988 989 out: 990 if (have_read) 991 rw_downgrade(&dn->dn_struct_rwlock); 992 } 993 994 void 995 dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) 996 { 997 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 998 avl_index_t where; 999 free_range_t *rp; 1000 free_range_t rp_tofind; 1001 uint64_t endblk = blkid + nblks; 1002 1003 ASSERT(MUTEX_HELD(&dn->dn_mtx)); 1004 ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ 1005 1006 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1007 blkid, nblks, tx->tx_txg); 1008 rp_tofind.fr_blkid = blkid; 1009 rp = avl_find(tree, &rp_tofind, &where); 1010 if (rp == NULL) 1011 rp = avl_nearest(tree, where, AVL_BEFORE); 1012 if (rp == NULL) 1013 rp = avl_nearest(tree, where, AVL_AFTER); 1014 1015 while (rp && (rp->fr_blkid <= blkid + nblks)) { 1016 uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; 1017 free_range_t *nrp = AVL_NEXT(tree, rp); 1018 1019 if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { 1020 /* clear this entire range */ 1021 avl_remove(tree, rp); 1022 kmem_free(rp, sizeof (free_range_t)); 1023 } else if (blkid <= rp->fr_blkid && 1024 endblk > rp->fr_blkid && endblk < fr_endblk) { 1025 /* clear the beginning of this range */ 1026 rp->fr_blkid = endblk; 1027 rp->fr_nblks = fr_endblk - endblk; 1028 } else if (blkid > rp->fr_blkid && blkid < fr_endblk && 1029 endblk >= fr_endblk) { 1030 /* clear the end of this range */ 1031 rp->fr_nblks = blkid - rp->fr_blkid; 1032 } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { 1033 /* clear a chunk out of this range */ 1034 free_range_t *new_rp = 1035 kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1036 1037 new_rp->fr_blkid = endblk; 1038 new_rp->fr_nblks = fr_endblk - endblk; 1039 avl_insert_here(tree, new_rp, rp, AVL_AFTER); 1040 rp->fr_nblks = blkid - rp->fr_blkid; 1041 } 1042 /* there may be no overlap */ 1043 rp = nrp; 1044 } 1045 } 1046 1047 void 1048 dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) 1049 { 1050 dmu_buf_impl_t *db; 1051 uint64_t blkoff, blkid, nblks; 1052 int blksz, blkshift, head, tail; 1053 int trunc = FALSE; 1054 int epbs; 1055 1056 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1057 blksz = dn->dn_datablksz; 1058 blkshift = dn->dn_datablkshift; 1059 epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 1060 1061 if (len == -1ULL) { 1062 len = UINT64_MAX - off; 1063 trunc = TRUE; 1064 } 1065 1066 /* 1067 * First, block align the region to free: 1068 */ 1069 if (ISP2(blksz)) { 1070 head = P2NPHASE(off, blksz); 1071 blkoff = P2PHASE(off, blksz); 1072 if ((off >> blkshift) > dn->dn_maxblkid) 1073 goto out; 1074 } else { 1075 ASSERT(dn->dn_maxblkid == 0); 1076 if (off == 0 && len >= blksz) { 1077 /* Freeing the whole block; fast-track this request */ 1078 blkid = 0; 1079 nblks = 1; 1080 goto done; 1081 } else if (off >= blksz) { 1082 /* Freeing past end-of-data */ 1083 goto out; 1084 } else { 1085 /* Freeing part of the block. */ 1086 head = blksz - off; 1087 ASSERT3U(head, >, 0); 1088 } 1089 blkoff = off; 1090 } 1091 /* zero out any partial block data at the start of the range */ 1092 if (head) { 1093 ASSERT3U(blkoff + head, ==, blksz); 1094 if (len < head) 1095 head = len; 1096 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, 1097 FTAG, &db) == 0) { 1098 caddr_t data; 1099 1100 /* don't dirty if it isn't on disk and isn't dirty */ 1101 if (db->db_last_dirty || 1102 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1103 rw_exit(&dn->dn_struct_rwlock); 1104 dbuf_will_dirty(db, tx); 1105 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1106 data = db->db.db_data; 1107 bzero(data + blkoff, head); 1108 } 1109 dbuf_rele(db, FTAG); 1110 } 1111 off += head; 1112 len -= head; 1113 } 1114 1115 /* If the range was less than one block, we're done */ 1116 if (len == 0) 1117 goto out; 1118 1119 /* If the remaining range is past end of file, we're done */ 1120 if ((off >> blkshift) > dn->dn_maxblkid) 1121 goto out; 1122 1123 ASSERT(ISP2(blksz)); 1124 if (trunc) 1125 tail = 0; 1126 else 1127 tail = P2PHASE(len, blksz); 1128 1129 ASSERT3U(P2PHASE(off, blksz), ==, 0); 1130 /* zero out any partial block data at the end of the range */ 1131 if (tail) { 1132 if (len < tail) 1133 tail = len; 1134 if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), 1135 TRUE, FTAG, &db) == 0) { 1136 /* don't dirty if not on disk and not dirty */ 1137 if (db->db_last_dirty || 1138 (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { 1139 rw_exit(&dn->dn_struct_rwlock); 1140 dbuf_will_dirty(db, tx); 1141 rw_enter(&dn->dn_struct_rwlock, RW_WRITER); 1142 bzero(db->db.db_data, tail); 1143 } 1144 dbuf_rele(db, FTAG); 1145 } 1146 len -= tail; 1147 } 1148 1149 /* If the range did not include a full block, we are done */ 1150 if (len == 0) 1151 goto out; 1152 1153 ASSERT(IS_P2ALIGNED(off, blksz)); 1154 ASSERT(trunc || IS_P2ALIGNED(len, blksz)); 1155 blkid = off >> blkshift; 1156 nblks = len >> blkshift; 1157 if (trunc) 1158 nblks += 1; 1159 1160 /* 1161 * Read in and mark all the level-1 indirects dirty, 1162 * so that they will stay in memory until syncing phase. 1163 * Always dirty the first and last indirect to make sure 1164 * we dirty all the partial indirects. 1165 */ 1166 if (dn->dn_nlevels > 1) { 1167 uint64_t i, first, last; 1168 int shift = epbs + dn->dn_datablkshift; 1169 1170 first = blkid >> epbs; 1171 if (db = dbuf_hold_level(dn, 1, first, FTAG)) { 1172 dbuf_will_dirty(db, tx); 1173 dbuf_rele(db, FTAG); 1174 } 1175 if (trunc) 1176 last = dn->dn_maxblkid >> epbs; 1177 else 1178 last = (blkid + nblks - 1) >> epbs; 1179 if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { 1180 dbuf_will_dirty(db, tx); 1181 dbuf_rele(db, FTAG); 1182 } 1183 for (i = first + 1; i < last; i++) { 1184 uint64_t ibyte = i << shift; 1185 int err; 1186 1187 err = dnode_next_offset(dn, 1188 DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); 1189 i = ibyte >> shift; 1190 if (err == ESRCH || i >= last) 1191 break; 1192 ASSERT(err == 0); 1193 db = dbuf_hold_level(dn, 1, i, FTAG); 1194 if (db) { 1195 dbuf_will_dirty(db, tx); 1196 dbuf_rele(db, FTAG); 1197 } 1198 } 1199 } 1200 done: 1201 /* 1202 * Add this range to the dnode range list. 1203 * We will finish up this free operation in the syncing phase. 1204 */ 1205 mutex_enter(&dn->dn_mtx); 1206 dnode_clear_range(dn, blkid, nblks, tx); 1207 { 1208 free_range_t *rp, *found; 1209 avl_index_t where; 1210 avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; 1211 1212 /* Add new range to dn_ranges */ 1213 rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); 1214 rp->fr_blkid = blkid; 1215 rp->fr_nblks = nblks; 1216 found = avl_find(tree, rp, &where); 1217 ASSERT(found == NULL); 1218 avl_insert(tree, rp, where); 1219 dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", 1220 blkid, nblks, tx->tx_txg); 1221 } 1222 mutex_exit(&dn->dn_mtx); 1223 1224 dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); 1225 dnode_setdirty(dn, tx); 1226 out: 1227 if (trunc && dn->dn_maxblkid >= (off >> blkshift)) 1228 dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); 1229 1230 rw_exit(&dn->dn_struct_rwlock); 1231 } 1232 1233 static boolean_t 1234 dnode_spill_freed(dnode_t *dn) 1235 { 1236 int i; 1237 1238 mutex_enter(&dn->dn_mtx); 1239 for (i = 0; i < TXG_SIZE; i++) { 1240 if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) 1241 break; 1242 } 1243 mutex_exit(&dn->dn_mtx); 1244 return (i < TXG_SIZE); 1245 } 1246 1247 /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ 1248 uint64_t 1249 dnode_block_freed(dnode_t *dn, uint64_t blkid) 1250 { 1251 free_range_t range_tofind; 1252 void *dp = spa_get_dsl(dn->dn_objset->os_spa); 1253 int i; 1254 1255 if (blkid == DMU_BONUS_BLKID) 1256 return (FALSE); 1257 1258 /* 1259 * If we're in the process of opening the pool, dp will not be 1260 * set yet, but there shouldn't be anything dirty. 1261 */ 1262 if (dp == NULL) 1263 return (FALSE); 1264 1265 if (dn->dn_free_txg) 1266 return (TRUE); 1267 1268 if (blkid == DMU_SPILL_BLKID) 1269 return (dnode_spill_freed(dn)); 1270 1271 range_tofind.fr_blkid = blkid; 1272 mutex_enter(&dn->dn_mtx); 1273 for (i = 0; i < TXG_SIZE; i++) { 1274 free_range_t *range_found; 1275 avl_index_t idx; 1276 1277 range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); 1278 if (range_found) { 1279 ASSERT(range_found->fr_nblks > 0); 1280 break; 1281 } 1282 range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); 1283 if (range_found && 1284 range_found->fr_blkid + range_found->fr_nblks > blkid) 1285 break; 1286 } 1287 mutex_exit(&dn->dn_mtx); 1288 return (i < TXG_SIZE); 1289 } 1290 1291 /* call from syncing context when we actually write/free space for this dnode */ 1292 void 1293 dnode_diduse_space(dnode_t *dn, int64_t delta) 1294 { 1295 uint64_t space; 1296 dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", 1297 dn, dn->dn_phys, 1298 (u_longlong_t)dn->dn_phys->dn_used, 1299 (longlong_t)delta); 1300 1301 mutex_enter(&dn->dn_mtx); 1302 space = DN_USED_BYTES(dn->dn_phys); 1303 if (delta > 0) { 1304 ASSERT3U(space + delta, >=, space); /* no overflow */ 1305 } else { 1306 ASSERT3U(space, >=, -delta); /* no underflow */ 1307 } 1308 space += delta; 1309 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { 1310 ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); 1311 ASSERT3U(P2PHASE(space, 1<<DEV_BSHIFT), ==, 0); 1312 dn->dn_phys->dn_used = space >> DEV_BSHIFT; 1313 } else { 1314 dn->dn_phys->dn_used = space; 1315 dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; 1316 } 1317 mutex_exit(&dn->dn_mtx); 1318 } 1319 1320 /* 1321 * Call when we think we're going to write/free space in open context. 1322 * Be conservative (ie. OK to write less than this or free more than 1323 * this, but don't write more or free less). 1324 */ 1325 void 1326 dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) 1327 { 1328 objset_t *os = dn->dn_objset; 1329 dsl_dataset_t *ds = os->os_dsl_dataset; 1330 1331 if (space > 0) 1332 space = spa_get_asize(os->os_spa, space); 1333 1334 if (ds) 1335 dsl_dir_willuse_space(ds->ds_dir, space, tx); 1336 1337 dmu_tx_willuse_space(tx, space); 1338 } 1339 1340 /* 1341 * This function scans a block at the indicated "level" looking for 1342 * a hole or data (depending on 'flags'). If level > 0, then we are 1343 * scanning an indirect block looking at its pointers. If level == 0, 1344 * then we are looking at a block of dnodes. If we don't find what we 1345 * are looking for in the block, we return ESRCH. Otherwise, return 1346 * with *offset pointing to the beginning (if searching forwards) or 1347 * end (if searching backwards) of the range covered by the block 1348 * pointer we matched on (or dnode). 1349 * 1350 * The basic search algorithm used below by dnode_next_offset() is to 1351 * use this function to search up the block tree (widen the search) until 1352 * we find something (i.e., we don't return ESRCH) and then search back 1353 * down the tree (narrow the search) until we reach our original search 1354 * level. 1355 */ 1356 static int 1357 dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, 1358 int lvl, uint64_t blkfill, uint64_t txg) 1359 { 1360 dmu_buf_impl_t *db = NULL; 1361 void *data = NULL; 1362 uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; 1363 uint64_t epb = 1ULL << epbs; 1364 uint64_t minfill, maxfill; 1365 boolean_t hole; 1366 int i, inc, error, span; 1367 1368 dprintf("probing object %llu offset %llx level %d of %u\n", 1369 dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); 1370 1371 hole = ((flags & DNODE_FIND_HOLE) != 0); 1372 inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; 1373 ASSERT(txg == 0 || !hole); 1374 1375 if (lvl == dn->dn_phys->dn_nlevels) { 1376 error = 0; 1377 epb = dn->dn_phys->dn_nblkptr; 1378 data = dn->dn_phys->dn_blkptr; 1379 } else { 1380 uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); 1381 error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); 1382 if (error) { 1383 if (error != ENOENT) 1384 return (error); 1385 if (hole) 1386 return (0); 1387 /* 1388 * This can only happen when we are searching up 1389 * the block tree for data. We don't really need to 1390 * adjust the offset, as we will just end up looking 1391 * at the pointer to this block in its parent, and its 1392 * going to be unallocated, so we will skip over it. 1393 */ 1394 return (ESRCH); 1395 } 1396 error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); 1397 if (error) { 1398 dbuf_rele(db, FTAG); 1399 return (error); 1400 } 1401 data = db->db.db_data; 1402 } 1403 1404 if (db && txg && 1405 (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { 1406 /* 1407 * This can only happen when we are searching up the tree 1408 * and these conditions mean that we need to keep climbing. 1409 */ 1410 error = ESRCH; 1411 } else if (lvl == 0) { 1412 dnode_phys_t *dnp = data; 1413 span = DNODE_SHIFT; 1414 ASSERT(dn->dn_type == DMU_OT_DNODE); 1415 1416 for (i = (*offset >> span) & (blkfill - 1); 1417 i >= 0 && i < blkfill; i += inc) { 1418 if ((dnp[i].dn_type == DMU_OT_NONE) == hole) 1419 break; 1420 *offset += (1ULL << span) * inc; 1421 } 1422 if (i < 0 || i == blkfill) 1423 error = ESRCH; 1424 } else { 1425 blkptr_t *bp = data; 1426 uint64_t start = *offset; 1427 span = (lvl - 1) * epbs + dn->dn_datablkshift; 1428 minfill = 0; 1429 maxfill = blkfill << ((lvl - 1) * epbs); 1430 1431 if (hole) 1432 maxfill--; 1433 else 1434 minfill++; 1435 1436 *offset = *offset >> span; 1437 for (i = BF64_GET(*offset, 0, epbs); 1438 i >= 0 && i < epb; i += inc) { 1439 if (bp[i].blk_fill >= minfill && 1440 bp[i].blk_fill <= maxfill && 1441 (hole || bp[i].blk_birth > txg)) 1442 break; 1443 if (inc > 0 || *offset > 0) 1444 *offset += inc; 1445 } 1446 *offset = *offset << span; 1447 if (inc < 0) { 1448 /* traversing backwards; position offset at the end */ 1449 ASSERT3U(*offset, <=, start); 1450 *offset = MIN(*offset + (1ULL << span) - 1, start); 1451 } else if (*offset < start) { 1452 *offset = start; 1453 } 1454 if (i < 0 || i >= epb) 1455 error = ESRCH; 1456 } 1457 1458 if (db) 1459 dbuf_rele(db, FTAG); 1460 1461 return (error); 1462 } 1463 1464 /* 1465 * Find the next hole, data, or sparse region at or after *offset. 1466 * The value 'blkfill' tells us how many items we expect to find 1467 * in an L0 data block; this value is 1 for normal objects, 1468 * DNODES_PER_BLOCK for the meta dnode, and some fraction of 1469 * DNODES_PER_BLOCK when searching for sparse regions thereof. 1470 * 1471 * Examples: 1472 * 1473 * dnode_next_offset(dn, flags, offset, 1, 1, 0); 1474 * Finds the next/previous hole/data in a file. 1475 * Used in dmu_offset_next(). 1476 * 1477 * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); 1478 * Finds the next free/allocated dnode an objset's meta-dnode. 1479 * Only finds objects that have new contents since txg (ie. 1480 * bonus buffer changes and content removal are ignored). 1481 * Used in dmu_object_next(). 1482 * 1483 * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); 1484 * Finds the next L2 meta-dnode bp that's at most 1/4 full. 1485 * Used in dmu_object_alloc(). 1486 */ 1487 int 1488 dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, 1489 int minlvl, uint64_t blkfill, uint64_t txg) 1490 { 1491 uint64_t initial_offset = *offset; 1492 int lvl, maxlvl; 1493 int error = 0; 1494 1495 if (!(flags & DNODE_FIND_HAVELOCK)) 1496 rw_enter(&dn->dn_struct_rwlock, RW_READER); 1497 1498 if (dn->dn_phys->dn_nlevels == 0) { 1499 error = ESRCH; 1500 goto out; 1501 } 1502 1503 if (dn->dn_datablkshift == 0) { 1504 if (*offset < dn->dn_datablksz) { 1505 if (flags & DNODE_FIND_HOLE) 1506 *offset = dn->dn_datablksz; 1507 } else { 1508 error = ESRCH; 1509 } 1510 goto out; 1511 } 1512 1513 maxlvl = dn->dn_phys->dn_nlevels; 1514 1515 for (lvl = minlvl; lvl <= maxlvl; lvl++) { 1516 error = dnode_next_offset_level(dn, 1517 flags, offset, lvl, blkfill, txg); 1518 if (error != ESRCH) 1519 break; 1520 } 1521 1522 while (error == 0 && --lvl >= minlvl) { 1523 error = dnode_next_offset_level(dn, 1524 flags, offset, lvl, blkfill, txg); 1525 } 1526 1527 if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? 1528 initial_offset < *offset : initial_offset > *offset)) 1529 error = ESRCH; 1530 out: 1531 if (!(flags & DNODE_FIND_HAVELOCK)) 1532 rw_exit(&dn->dn_struct_rwlock); 1533 1534 return (error); 1535 } 1536