1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/spa.h> 29 #include <sys/dmu.h> 30 #include <sys/zfs_context.h> 31 #include <sys/zap.h> 32 #include <sys/refcount.h> 33 #include <sys/zap_impl.h> 34 #include <sys/zap_leaf.h> 35 #include <sys/avl.h> 36 37 38 static void mzap_upgrade(zap_t *zap, dmu_tx_t *tx); 39 40 41 static void 42 mzap_byteswap(mzap_phys_t *buf, size_t size) 43 { 44 int i, max; 45 buf->mz_block_type = BSWAP_64(buf->mz_block_type); 46 buf->mz_salt = BSWAP_64(buf->mz_salt); 47 max = (size / MZAP_ENT_LEN) - 1; 48 for (i = 0; i < max; i++) { 49 buf->mz_chunk[i].mze_value = 50 BSWAP_64(buf->mz_chunk[i].mze_value); 51 buf->mz_chunk[i].mze_cd = 52 BSWAP_32(buf->mz_chunk[i].mze_cd); 53 } 54 } 55 56 void 57 zap_byteswap(void *buf, size_t size) 58 { 59 uint64_t block_type; 60 61 block_type = *(uint64_t *)buf; 62 63 if (block_type == ZBT_MICRO || block_type == BSWAP_64(ZBT_MICRO)) { 64 /* ASSERT(magic == ZAP_LEAF_MAGIC); */ 65 mzap_byteswap(buf, size); 66 } else { 67 fzap_byteswap(buf, size); 68 } 69 } 70 71 static int 72 mze_compare(const void *arg1, const void *arg2) 73 { 74 const mzap_ent_t *mze1 = arg1; 75 const mzap_ent_t *mze2 = arg2; 76 77 if (mze1->mze_hash > mze2->mze_hash) 78 return (+1); 79 if (mze1->mze_hash < mze2->mze_hash) 80 return (-1); 81 if (mze1->mze_phys.mze_cd > mze2->mze_phys.mze_cd) 82 return (+1); 83 if (mze1->mze_phys.mze_cd < mze2->mze_phys.mze_cd) 84 return (-1); 85 return (0); 86 } 87 88 static void 89 mze_insert(zap_t *zap, int chunkid, uint64_t hash, mzap_ent_phys_t *mzep) 90 { 91 mzap_ent_t *mze; 92 93 ASSERT(zap->zap_ismicro); 94 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 95 ASSERT(mzep->mze_cd < ZAP_MAXCD); 96 ASSERT3U(zap_hash(zap, mzep->mze_name), ==, hash); 97 98 mze = kmem_alloc(sizeof (mzap_ent_t), KM_SLEEP); 99 mze->mze_chunkid = chunkid; 100 mze->mze_hash = hash; 101 mze->mze_phys = *mzep; 102 avl_add(&zap->zap_m.zap_avl, mze); 103 } 104 105 static mzap_ent_t * 106 mze_find(zap_t *zap, const char *name, uint64_t hash) 107 { 108 mzap_ent_t mze_tofind; 109 mzap_ent_t *mze; 110 avl_index_t idx; 111 avl_tree_t *avl = &zap->zap_m.zap_avl; 112 113 ASSERT(zap->zap_ismicro); 114 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 115 ASSERT3U(zap_hash(zap, name), ==, hash); 116 117 if (strlen(name) >= sizeof (mze_tofind.mze_phys.mze_name)) 118 return (NULL); 119 120 mze_tofind.mze_hash = hash; 121 mze_tofind.mze_phys.mze_cd = 0; 122 123 mze = avl_find(avl, &mze_tofind, &idx); 124 if (mze == NULL) 125 mze = avl_nearest(avl, idx, AVL_AFTER); 126 for (; mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) { 127 if (strcmp(name, mze->mze_phys.mze_name) == 0) 128 return (mze); 129 } 130 return (NULL); 131 } 132 133 static uint32_t 134 mze_find_unused_cd(zap_t *zap, uint64_t hash) 135 { 136 mzap_ent_t mze_tofind; 137 mzap_ent_t *mze; 138 avl_index_t idx; 139 avl_tree_t *avl = &zap->zap_m.zap_avl; 140 uint32_t cd; 141 142 ASSERT(zap->zap_ismicro); 143 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 144 145 mze_tofind.mze_hash = hash; 146 mze_tofind.mze_phys.mze_cd = 0; 147 148 cd = 0; 149 for (mze = avl_find(avl, &mze_tofind, &idx); 150 mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) { 151 if (mze->mze_phys.mze_cd != cd) 152 break; 153 cd++; 154 } 155 156 return (cd); 157 } 158 159 static void 160 mze_remove(zap_t *zap, mzap_ent_t *mze) 161 { 162 ASSERT(zap->zap_ismicro); 163 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 164 165 avl_remove(&zap->zap_m.zap_avl, mze); 166 kmem_free(mze, sizeof (mzap_ent_t)); 167 } 168 169 static void 170 mze_destroy(zap_t *zap) 171 { 172 mzap_ent_t *mze; 173 void *avlcookie = NULL; 174 175 while (mze = avl_destroy_nodes(&zap->zap_m.zap_avl, &avlcookie)) 176 kmem_free(mze, sizeof (mzap_ent_t)); 177 avl_destroy(&zap->zap_m.zap_avl); 178 } 179 180 static zap_t * 181 mzap_open(objset_t *os, uint64_t obj, dmu_buf_t *db) 182 { 183 zap_t *winner; 184 zap_t *zap; 185 int i; 186 187 ASSERT3U(MZAP_ENT_LEN, ==, sizeof (mzap_ent_phys_t)); 188 189 zap = kmem_zalloc(sizeof (zap_t), KM_SLEEP); 190 rw_init(&zap->zap_rwlock, 0, 0, 0); 191 rw_enter(&zap->zap_rwlock, RW_WRITER); 192 zap->zap_objset = os; 193 zap->zap_object = obj; 194 zap->zap_dbuf = db; 195 196 if (((uint64_t *)db->db_data)[0] != ZBT_MICRO) { 197 mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0); 198 zap->zap_f.zap_block_shift = highbit(db->db_size) - 1; 199 } else { 200 zap->zap_ismicro = TRUE; 201 } 202 203 /* 204 * Make sure that zap_ismicro is set before we let others see 205 * it, because zap_lockdir() checks zap_ismicro without the lock 206 * held. 207 */ 208 winner = dmu_buf_set_user(db, zap, &zap->zap_m.zap_phys, zap_evict); 209 210 if (winner != NULL) { 211 rw_exit(&zap->zap_rwlock); 212 rw_destroy(&zap->zap_rwlock); 213 if (!zap->zap_ismicro) 214 mutex_destroy(&zap->zap_f.zap_num_entries_mtx); 215 kmem_free(zap, sizeof (zap_t)); 216 return (winner); 217 } 218 219 if (zap->zap_ismicro) { 220 zap->zap_salt = zap->zap_m.zap_phys->mz_salt; 221 zap->zap_m.zap_num_chunks = db->db_size / MZAP_ENT_LEN - 1; 222 avl_create(&zap->zap_m.zap_avl, mze_compare, 223 sizeof (mzap_ent_t), offsetof(mzap_ent_t, mze_node)); 224 225 for (i = 0; i < zap->zap_m.zap_num_chunks; i++) { 226 mzap_ent_phys_t *mze = 227 &zap->zap_m.zap_phys->mz_chunk[i]; 228 if (mze->mze_name[0]) { 229 zap->zap_m.zap_num_entries++; 230 mze_insert(zap, i, 231 zap_hash(zap, mze->mze_name), mze); 232 } 233 } 234 } else { 235 zap->zap_salt = zap->zap_f.zap_phys->zap_salt; 236 237 ASSERT3U(sizeof (struct zap_leaf_header), ==, 238 2*ZAP_LEAF_CHUNKSIZE); 239 240 /* 241 * The embedded pointer table should not overlap the 242 * other members. 243 */ 244 ASSERT3P(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), >, 245 &zap->zap_f.zap_phys->zap_salt); 246 247 /* 248 * The embedded pointer table should end at the end of 249 * the block 250 */ 251 ASSERT3U((uintptr_t)&ZAP_EMBEDDED_PTRTBL_ENT(zap, 252 1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)) - 253 (uintptr_t)zap->zap_f.zap_phys, ==, 254 zap->zap_dbuf->db_size); 255 } 256 rw_exit(&zap->zap_rwlock); 257 return (zap); 258 } 259 260 int 261 zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx, 262 krw_t lti, int fatreader, zap_t **zapp) 263 { 264 zap_t *zap; 265 dmu_buf_t *db; 266 krw_t lt; 267 int err; 268 269 *zapp = NULL; 270 271 err = dmu_buf_hold(os, obj, 0, NULL, &db); 272 if (err) 273 return (err); 274 275 #ifdef ZFS_DEBUG 276 { 277 dmu_object_info_t doi; 278 dmu_object_info_from_db(db, &doi); 279 ASSERT(dmu_ot[doi.doi_type].ot_byteswap == zap_byteswap); 280 } 281 #endif 282 283 zap = dmu_buf_get_user(db); 284 if (zap == NULL) 285 zap = mzap_open(os, obj, db); 286 287 /* 288 * We're checking zap_ismicro without the lock held, in order to 289 * tell what type of lock we want. Once we have some sort of 290 * lock, see if it really is the right type. In practice this 291 * can only be different if it was upgraded from micro to fat, 292 * and micro wanted WRITER but fat only needs READER. 293 */ 294 lt = (!zap->zap_ismicro && fatreader) ? RW_READER : lti; 295 rw_enter(&zap->zap_rwlock, lt); 296 if (lt != ((!zap->zap_ismicro && fatreader) ? RW_READER : lti)) { 297 /* it was upgraded, now we only need reader */ 298 ASSERT(lt == RW_WRITER); 299 ASSERT(RW_READER == 300 (!zap->zap_ismicro && fatreader) ? RW_READER : lti); 301 rw_downgrade(&zap->zap_rwlock); 302 lt = RW_READER; 303 } 304 305 zap->zap_objset = os; 306 307 if (lt == RW_WRITER) 308 dmu_buf_will_dirty(db, tx); 309 310 ASSERT3P(zap->zap_dbuf, ==, db); 311 312 ASSERT(!zap->zap_ismicro || 313 zap->zap_m.zap_num_entries <= zap->zap_m.zap_num_chunks); 314 if (zap->zap_ismicro && tx && 315 zap->zap_m.zap_num_entries == zap->zap_m.zap_num_chunks) { 316 uint64_t newsz = db->db_size + SPA_MINBLOCKSIZE; 317 if (newsz > MZAP_MAX_BLKSZ) { 318 dprintf("upgrading obj %llu: num_entries=%u\n", 319 obj, zap->zap_m.zap_num_entries); 320 mzap_upgrade(zap, tx); 321 *zapp = zap; 322 return (0); 323 } 324 err = dmu_object_set_blocksize(os, obj, newsz, 0, tx); 325 ASSERT3U(err, ==, 0); 326 zap->zap_m.zap_num_chunks = 327 db->db_size / MZAP_ENT_LEN - 1; 328 } 329 330 *zapp = zap; 331 return (0); 332 } 333 334 void 335 zap_unlockdir(zap_t *zap) 336 { 337 rw_exit(&zap->zap_rwlock); 338 dmu_buf_rele(zap->zap_dbuf, NULL); 339 } 340 341 static void 342 mzap_upgrade(zap_t *zap, dmu_tx_t *tx) 343 { 344 mzap_phys_t *mzp; 345 int i, sz, nchunks, err; 346 347 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 348 349 sz = zap->zap_dbuf->db_size; 350 mzp = kmem_alloc(sz, KM_SLEEP); 351 bcopy(zap->zap_dbuf->db_data, mzp, sz); 352 nchunks = zap->zap_m.zap_num_chunks; 353 354 err = dmu_object_set_blocksize(zap->zap_objset, zap->zap_object, 355 1ULL << fzap_default_block_shift, 0, tx); 356 ASSERT(err == 0); 357 358 dprintf("upgrading obj=%llu with %u chunks\n", 359 zap->zap_object, nchunks); 360 mze_destroy(zap); 361 362 fzap_upgrade(zap, tx); 363 364 for (i = 0; i < nchunks; i++) { 365 int err; 366 mzap_ent_phys_t *mze = &mzp->mz_chunk[i]; 367 if (mze->mze_name[0] == 0) 368 continue; 369 dprintf("adding %s=%llu\n", 370 mze->mze_name, mze->mze_value); 371 err = fzap_add_cd(zap, 372 mze->mze_name, 8, 1, &mze->mze_value, 373 mze->mze_cd, tx); 374 ASSERT3U(err, ==, 0); 375 } 376 kmem_free(mzp, sz); 377 } 378 379 uint64_t 380 zap_hash(zap_t *zap, const char *name) 381 { 382 const uint8_t *cp; 383 uint8_t c; 384 uint64_t crc = zap->zap_salt; 385 386 ASSERT(crc != 0); 387 ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY); 388 for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++) 389 crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ c) & 0xFF]; 390 391 /* 392 * Only use 28 bits, since we need 4 bits in the cookie for the 393 * collision differentiator. We MUST use the high bits, since 394 * those are the onces that we first pay attention to when 395 * chosing the bucket. 396 */ 397 crc &= ~((1ULL << (64 - ZAP_HASHBITS)) - 1); 398 399 return (crc); 400 } 401 402 403 static void 404 mzap_create_impl(objset_t *os, uint64_t obj, dmu_tx_t *tx) 405 { 406 dmu_buf_t *db; 407 mzap_phys_t *zp; 408 409 VERIFY(0 == dmu_buf_hold(os, obj, 0, FTAG, &db)); 410 411 #ifdef ZFS_DEBUG 412 { 413 dmu_object_info_t doi; 414 dmu_object_info_from_db(db, &doi); 415 ASSERT(dmu_ot[doi.doi_type].ot_byteswap == zap_byteswap); 416 } 417 #endif 418 419 dmu_buf_will_dirty(db, tx); 420 zp = db->db_data; 421 zp->mz_block_type = ZBT_MICRO; 422 zp->mz_salt = ((uintptr_t)db ^ (uintptr_t)tx ^ (obj << 1)) | 1ULL; 423 ASSERT(zp->mz_salt != 0); 424 dmu_buf_rele(db, FTAG); 425 } 426 427 int 428 zap_create_claim(objset_t *os, uint64_t obj, dmu_object_type_t ot, 429 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 430 { 431 int err; 432 433 err = dmu_object_claim(os, obj, ot, 0, bonustype, bonuslen, tx); 434 if (err != 0) 435 return (err); 436 mzap_create_impl(os, obj, tx); 437 return (0); 438 } 439 440 uint64_t 441 zap_create(objset_t *os, dmu_object_type_t ot, 442 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) 443 { 444 uint64_t obj = dmu_object_alloc(os, ot, 0, bonustype, bonuslen, tx); 445 446 mzap_create_impl(os, obj, tx); 447 return (obj); 448 } 449 450 int 451 zap_destroy(objset_t *os, uint64_t zapobj, dmu_tx_t *tx) 452 { 453 /* 454 * dmu_object_free will free the object number and free the 455 * data. Freeing the data will cause our pageout function to be 456 * called, which will destroy our data (zap_leaf_t's and zap_t). 457 */ 458 459 return (dmu_object_free(os, zapobj, tx)); 460 } 461 462 _NOTE(ARGSUSED(0)) 463 void 464 zap_evict(dmu_buf_t *db, void *vzap) 465 { 466 zap_t *zap = vzap; 467 468 rw_destroy(&zap->zap_rwlock); 469 470 if (zap->zap_ismicro) 471 mze_destroy(zap); 472 else 473 mutex_destroy(&zap->zap_f.zap_num_entries_mtx); 474 475 kmem_free(zap, sizeof (zap_t)); 476 } 477 478 int 479 zap_count(objset_t *os, uint64_t zapobj, uint64_t *count) 480 { 481 zap_t *zap; 482 int err; 483 484 err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); 485 if (err) 486 return (err); 487 if (!zap->zap_ismicro) { 488 err = fzap_count(zap, count); 489 } else { 490 *count = zap->zap_m.zap_num_entries; 491 } 492 zap_unlockdir(zap); 493 return (err); 494 } 495 496 /* 497 * Routines for maniplulating attributes. 498 */ 499 500 int 501 zap_lookup(objset_t *os, uint64_t zapobj, const char *name, 502 uint64_t integer_size, uint64_t num_integers, void *buf) 503 { 504 zap_t *zap; 505 int err; 506 mzap_ent_t *mze; 507 508 err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); 509 if (err) 510 return (err); 511 if (!zap->zap_ismicro) { 512 err = fzap_lookup(zap, name, 513 integer_size, num_integers, buf); 514 } else { 515 mze = mze_find(zap, name, zap_hash(zap, name)); 516 if (mze == NULL) { 517 err = ENOENT; 518 } else { 519 if (num_integers < 1) 520 err = EOVERFLOW; 521 else if (integer_size != 8) 522 err = EINVAL; 523 else 524 *(uint64_t *)buf = mze->mze_phys.mze_value; 525 } 526 } 527 zap_unlockdir(zap); 528 return (err); 529 } 530 531 int 532 zap_length(objset_t *os, uint64_t zapobj, const char *name, 533 uint64_t *integer_size, uint64_t *num_integers) 534 { 535 zap_t *zap; 536 int err; 537 mzap_ent_t *mze; 538 539 err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); 540 if (err) 541 return (err); 542 if (!zap->zap_ismicro) { 543 err = fzap_length(zap, name, integer_size, num_integers); 544 } else { 545 mze = mze_find(zap, name, zap_hash(zap, name)); 546 if (mze == NULL) { 547 err = ENOENT; 548 } else { 549 if (integer_size) 550 *integer_size = 8; 551 if (num_integers) 552 *num_integers = 1; 553 } 554 } 555 zap_unlockdir(zap); 556 return (err); 557 } 558 559 static void 560 mzap_addent(zap_t *zap, const char *name, uint64_t hash, uint64_t value) 561 { 562 int i; 563 int start = zap->zap_m.zap_alloc_next; 564 uint32_t cd; 565 566 dprintf("obj=%llu %s=%llu\n", zap->zap_object, name, value); 567 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 568 569 #ifdef ZFS_DEBUG 570 for (i = 0; i < zap->zap_m.zap_num_chunks; i++) { 571 mzap_ent_phys_t *mze = &zap->zap_m.zap_phys->mz_chunk[i]; 572 ASSERT(strcmp(name, mze->mze_name) != 0); 573 } 574 #endif 575 576 cd = mze_find_unused_cd(zap, hash); 577 /* given the limited size of the microzap, this can't happen */ 578 ASSERT(cd != ZAP_MAXCD); 579 580 again: 581 for (i = start; i < zap->zap_m.zap_num_chunks; i++) { 582 mzap_ent_phys_t *mze = &zap->zap_m.zap_phys->mz_chunk[i]; 583 if (mze->mze_name[0] == 0) { 584 mze->mze_value = value; 585 mze->mze_cd = cd; 586 (void) strcpy(mze->mze_name, name); 587 zap->zap_m.zap_num_entries++; 588 zap->zap_m.zap_alloc_next = i+1; 589 if (zap->zap_m.zap_alloc_next == 590 zap->zap_m.zap_num_chunks) 591 zap->zap_m.zap_alloc_next = 0; 592 mze_insert(zap, i, hash, mze); 593 return; 594 } 595 } 596 if (start != 0) { 597 start = 0; 598 goto again; 599 } 600 ASSERT(!"out of entries!"); 601 } 602 603 int 604 zap_add(objset_t *os, uint64_t zapobj, const char *name, 605 int integer_size, uint64_t num_integers, 606 const void *val, dmu_tx_t *tx) 607 { 608 zap_t *zap; 609 int err; 610 mzap_ent_t *mze; 611 const uint64_t *intval = val; 612 uint64_t hash; 613 614 err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); 615 if (err) 616 return (err); 617 if (!zap->zap_ismicro) { 618 err = fzap_add(zap, name, integer_size, num_integers, val, tx); 619 } else if (integer_size != 8 || num_integers != 1 || 620 strlen(name) >= MZAP_NAME_LEN) { 621 dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n", 622 zapobj, integer_size, num_integers, name); 623 mzap_upgrade(zap, tx); 624 err = fzap_add(zap, name, integer_size, num_integers, val, tx); 625 } else { 626 hash = zap_hash(zap, name); 627 mze = mze_find(zap, name, hash); 628 if (mze != NULL) { 629 err = EEXIST; 630 } else { 631 mzap_addent(zap, name, hash, *intval); 632 } 633 } 634 zap_unlockdir(zap); 635 return (err); 636 } 637 638 int 639 zap_update(objset_t *os, uint64_t zapobj, const char *name, 640 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx) 641 { 642 zap_t *zap; 643 mzap_ent_t *mze; 644 const uint64_t *intval = val; 645 uint64_t hash; 646 int err; 647 648 err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); 649 if (err) 650 return (err); 651 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 652 if (!zap->zap_ismicro) { 653 err = fzap_update(zap, name, 654 integer_size, num_integers, val, tx); 655 } else if (integer_size != 8 || num_integers != 1 || 656 strlen(name) >= MZAP_NAME_LEN) { 657 dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n", 658 zapobj, integer_size, num_integers, name); 659 mzap_upgrade(zap, tx); 660 err = fzap_update(zap, name, 661 integer_size, num_integers, val, tx); 662 } else { 663 hash = zap_hash(zap, name); 664 mze = mze_find(zap, name, hash); 665 if (mze != NULL) { 666 mze->mze_phys.mze_value = *intval; 667 zap->zap_m.zap_phys->mz_chunk 668 [mze->mze_chunkid].mze_value = *intval; 669 } else { 670 mzap_addent(zap, name, hash, *intval); 671 } 672 } 673 zap_unlockdir(zap); 674 return (err); 675 } 676 677 int 678 zap_remove(objset_t *os, uint64_t zapobj, const char *name, dmu_tx_t *tx) 679 { 680 zap_t *zap; 681 int err; 682 mzap_ent_t *mze; 683 684 err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); 685 if (err) 686 return (err); 687 if (!zap->zap_ismicro) { 688 err = fzap_remove(zap, name, tx); 689 } else { 690 mze = mze_find(zap, name, zap_hash(zap, name)); 691 if (mze == NULL) { 692 dprintf("fail: %s\n", name); 693 err = ENOENT; 694 } else { 695 dprintf("success: %s\n", name); 696 zap->zap_m.zap_num_entries--; 697 bzero(&zap->zap_m.zap_phys->mz_chunk[mze->mze_chunkid], 698 sizeof (mzap_ent_phys_t)); 699 mze_remove(zap, mze); 700 } 701 } 702 zap_unlockdir(zap); 703 return (err); 704 } 705 706 707 /* 708 * Routines for iterating over the attributes. 709 */ 710 711 /* 712 * We want to keep the high 32 bits of the cursor zero if we can, so 713 * that 32-bit programs can access this. So use a small hash value so 714 * we can fit 4 bits of cd into the 32-bit cursor. 715 * 716 * [ 4 zero bits | 32-bit collision differentiator | 28-bit hash value ] 717 */ 718 void 719 zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *os, uint64_t zapobj, 720 uint64_t serialized) 721 { 722 zc->zc_objset = os; 723 zc->zc_zap = NULL; 724 zc->zc_leaf = NULL; 725 zc->zc_zapobj = zapobj; 726 if (serialized == -1ULL) { 727 zc->zc_hash = -1ULL; 728 zc->zc_cd = 0; 729 } else { 730 zc->zc_hash = serialized << (64-ZAP_HASHBITS); 731 zc->zc_cd = serialized >> ZAP_HASHBITS; 732 if (zc->zc_cd >= ZAP_MAXCD) /* corrupt serialized */ 733 zc->zc_cd = 0; 734 } 735 } 736 737 void 738 zap_cursor_init(zap_cursor_t *zc, objset_t *os, uint64_t zapobj) 739 { 740 zap_cursor_init_serialized(zc, os, zapobj, 0); 741 } 742 743 void 744 zap_cursor_fini(zap_cursor_t *zc) 745 { 746 if (zc->zc_zap) { 747 rw_enter(&zc->zc_zap->zap_rwlock, RW_READER); 748 zap_unlockdir(zc->zc_zap); 749 zc->zc_zap = NULL; 750 } 751 if (zc->zc_leaf) { 752 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); 753 zap_put_leaf(zc->zc_leaf); 754 zc->zc_leaf = NULL; 755 } 756 zc->zc_objset = NULL; 757 } 758 759 uint64_t 760 zap_cursor_serialize(zap_cursor_t *zc) 761 { 762 if (zc->zc_hash == -1ULL) 763 return (-1ULL); 764 ASSERT((zc->zc_hash & (ZAP_MAXCD-1)) == 0); 765 ASSERT(zc->zc_cd < ZAP_MAXCD); 766 return ((zc->zc_hash >> (64-ZAP_HASHBITS)) | 767 ((uint64_t)zc->zc_cd << ZAP_HASHBITS)); 768 } 769 770 int 771 zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za) 772 { 773 int err; 774 avl_index_t idx; 775 mzap_ent_t mze_tofind; 776 mzap_ent_t *mze; 777 778 if (zc->zc_hash == -1ULL) 779 return (ENOENT); 780 781 if (zc->zc_zap == NULL) { 782 err = zap_lockdir(zc->zc_objset, zc->zc_zapobj, NULL, 783 RW_READER, TRUE, &zc->zc_zap); 784 if (err) 785 return (err); 786 } else { 787 rw_enter(&zc->zc_zap->zap_rwlock, RW_READER); 788 } 789 if (!zc->zc_zap->zap_ismicro) { 790 err = fzap_cursor_retrieve(zc->zc_zap, zc, za); 791 } else { 792 err = ENOENT; 793 794 mze_tofind.mze_hash = zc->zc_hash; 795 mze_tofind.mze_phys.mze_cd = zc->zc_cd; 796 797 mze = avl_find(&zc->zc_zap->zap_m.zap_avl, &mze_tofind, &idx); 798 ASSERT(mze == NULL || 0 == bcmp(&mze->mze_phys, 799 &zc->zc_zap->zap_m.zap_phys->mz_chunk[mze->mze_chunkid], 800 sizeof (mze->mze_phys))); 801 if (mze == NULL) { 802 mze = avl_nearest(&zc->zc_zap->zap_m.zap_avl, 803 idx, AVL_AFTER); 804 } 805 if (mze) { 806 za->za_integer_length = 8; 807 za->za_num_integers = 1; 808 za->za_first_integer = mze->mze_phys.mze_value; 809 (void) strcpy(za->za_name, mze->mze_phys.mze_name); 810 zc->zc_hash = mze->mze_hash; 811 zc->zc_cd = mze->mze_phys.mze_cd; 812 err = 0; 813 } else { 814 zc->zc_hash = -1ULL; 815 } 816 } 817 rw_exit(&zc->zc_zap->zap_rwlock); 818 return (err); 819 } 820 821 void 822 zap_cursor_advance(zap_cursor_t *zc) 823 { 824 if (zc->zc_hash == -1ULL) 825 return; 826 zc->zc_cd++; 827 if (zc->zc_cd >= ZAP_MAXCD) { 828 zc->zc_cd = 0; 829 zc->zc_hash += 1ULL<<(64-ZAP_HASHBITS); 830 if (zc->zc_hash == 0) /* EOF */ 831 zc->zc_hash = -1ULL; 832 } 833 } 834 835 int 836 zap_get_stats(objset_t *os, uint64_t zapobj, zap_stats_t *zs) 837 { 838 int err; 839 zap_t *zap; 840 841 err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); 842 if (err) 843 return (err); 844 845 bzero(zs, sizeof (zap_stats_t)); 846 847 if (zap->zap_ismicro) { 848 zs->zs_blocksize = zap->zap_dbuf->db_size; 849 zs->zs_num_entries = zap->zap_m.zap_num_entries; 850 zs->zs_num_blocks = 1; 851 } else { 852 fzap_get_stats(zap, zs); 853 } 854 zap_unlockdir(zap); 855 return (0); 856 } 857