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 2006 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 29 /* 30 * This file contains the top half of the zfs directory structure 31 * implementation. The bottom half is in zap_leaf.c. 32 * 33 * The zdir is an extendable hash data structure. There is a table of 34 * pointers to buckets (zap_t->zd_data->zd_leafs). The buckets are 35 * each a constant size and hold a variable number of directory entries. 36 * The buckets (aka "leaf nodes") are implemented in zap_leaf.c. 37 * 38 * The pointer table holds a power of 2 number of pointers. 39 * (1<<zap_t->zd_data->zd_phys->zd_prefix_len). The bucket pointed to 40 * by the pointer at index i in the table holds entries whose hash value 41 * has a zd_prefix_len - bit prefix 42 */ 43 44 #include <sys/spa.h> 45 #include <sys/dmu.h> 46 #include <sys/zfs_context.h> 47 #include <sys/zap.h> 48 #include <sys/refcount.h> 49 #include <sys/zap_impl.h> 50 #include <sys/zap_leaf.h> 51 52 #define MIN_FREE(l) (ZAP_LEAF_NUMCHUNKS(l)*9/10) 53 54 int fzap_default_block_shift = 14; /* 16k blocksize */ 55 56 static void zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx); 57 static int zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx); 58 static int zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, 59 dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp); 60 static void zap_leaf_pageout(dmu_buf_t *db, void *vl); 61 62 63 void 64 fzap_byteswap(void *vbuf, size_t size) 65 { 66 uint64_t block_type; 67 68 block_type = *(uint64_t *)vbuf; 69 70 switch (block_type) { 71 case ZBT_LEAF: 72 case BSWAP_64(ZBT_LEAF): 73 zap_leaf_byteswap(vbuf, size); 74 return; 75 case ZBT_HEADER: 76 case BSWAP_64(ZBT_HEADER): 77 default: 78 /* it's a ptrtbl block */ 79 byteswap_uint64_array(vbuf, size); 80 return; 81 } 82 } 83 84 void 85 fzap_upgrade(zap_t *zap, dmu_tx_t *tx) 86 { 87 dmu_buf_t *db; 88 zap_leaf_t *l; 89 int i; 90 zap_phys_t *zp; 91 92 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 93 zap->zap_ismicro = FALSE; 94 95 (void) dmu_buf_update_user(zap->zap_dbuf, zap, zap, 96 &zap->zap_f.zap_phys, zap_pageout); 97 98 mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0); 99 zap->zap_f.zap_block_shift = highbit(zap->zap_dbuf->db_size) - 1; 100 101 zp = zap->zap_f.zap_phys; 102 /* 103 * explicitly zero it since it might be coming from an 104 * initialized microzap 105 */ 106 bzero(zap->zap_dbuf->db_data, zap->zap_dbuf->db_size); 107 zp->zap_block_type = ZBT_HEADER; 108 zp->zap_magic = ZAP_MAGIC; 109 110 zp->zap_ptrtbl.zt_shift = ZAP_EMBEDDED_PTRTBL_SHIFT(zap); 111 112 zp->zap_freeblk = 2; /* block 1 will be the first leaf */ 113 zp->zap_num_leafs = 1; 114 zp->zap_num_entries = 0; 115 zp->zap_salt = zap->zap_salt; 116 117 /* block 1 will be the first leaf */ 118 for (i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++) 119 ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1; 120 121 /* 122 * set up block 1 - the first leaf 123 */ 124 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 125 1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db)); 126 dmu_buf_will_dirty(db, tx); 127 128 l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP); 129 l->l_dbuf = db; 130 l->l_phys = db->db_data; 131 132 zap_leaf_init(l); 133 134 kmem_free(l, sizeof (zap_leaf_t)); 135 dmu_buf_rele(db, FTAG); 136 } 137 138 static int 139 zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx) 140 { 141 if (RW_WRITE_HELD(&zap->zap_rwlock)) 142 return (1); 143 if (rw_tryupgrade(&zap->zap_rwlock)) { 144 dmu_buf_will_dirty(zap->zap_dbuf, tx); 145 return (1); 146 } 147 return (0); 148 } 149 150 /* 151 * Generic routines for dealing with the pointer & cookie tables. 152 */ 153 154 static void 155 zap_table_grow(zap_t *zap, zap_table_phys_t *tbl, 156 void (*transfer_func)(const uint64_t *src, uint64_t *dst, int n), 157 dmu_tx_t *tx) 158 { 159 uint64_t b, newblk; 160 dmu_buf_t *db_old, *db_new; 161 int err; 162 int bs = FZAP_BLOCK_SHIFT(zap); 163 int hepb = 1<<(bs-4); 164 /* hepb = half the number of entries in a block */ 165 166 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 167 ASSERT(tbl->zt_blk != 0); 168 ASSERT(tbl->zt_numblks > 0); 169 170 if (tbl->zt_nextblk != 0) { 171 newblk = tbl->zt_nextblk; 172 } else { 173 newblk = zap_allocate_blocks(zap, tbl->zt_numblks * 2, tx); 174 tbl->zt_nextblk = newblk; 175 ASSERT3U(tbl->zt_blks_copied, ==, 0); 176 dmu_prefetch(zap->zap_objset, zap->zap_object, 177 tbl->zt_blk << bs, tbl->zt_numblks << bs); 178 } 179 180 /* 181 * Copy the ptrtbl from the old to new location, leaving the odd 182 * entries blank as we go. 183 */ 184 185 b = tbl->zt_blks_copied; 186 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 187 (tbl->zt_blk + b) << bs, FTAG, &db_old); 188 if (err) 189 return; 190 191 /* first half of entries in old[b] go to new[2*b+0] */ 192 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 193 (newblk + 2*b+0) << bs, FTAG, &db_new)); 194 dmu_buf_will_dirty(db_new, tx); 195 transfer_func(db_old->db_data, db_new->db_data, hepb); 196 dmu_buf_rele(db_new, FTAG); 197 198 /* second half of entries in old[b] go to new[2*b+1] */ 199 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 200 (newblk + 2*b+1) << bs, FTAG, &db_new)); 201 dmu_buf_will_dirty(db_new, tx); 202 transfer_func((uint64_t *)db_old->db_data + hepb, 203 db_new->db_data, hepb); 204 dmu_buf_rele(db_new, FTAG); 205 206 dmu_buf_rele(db_old, FTAG); 207 208 tbl->zt_blks_copied++; 209 210 dprintf("copied block %llu of %llu\n", 211 tbl->zt_blks_copied, tbl->zt_numblks); 212 213 if (tbl->zt_blks_copied == tbl->zt_numblks) { 214 (void) dmu_free_range(zap->zap_objset, zap->zap_object, 215 tbl->zt_blk << bs, tbl->zt_numblks << bs, tx); 216 217 tbl->zt_blk = newblk; 218 tbl->zt_numblks *= 2; 219 tbl->zt_shift++; 220 tbl->zt_nextblk = 0; 221 tbl->zt_blks_copied = 0; 222 223 dprintf("finished; numblocks now %llu (%lluk entries)\n", 224 tbl->zt_numblks, 1<<(tbl->zt_shift-10)); 225 } 226 } 227 228 static int 229 zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val, 230 dmu_tx_t *tx) 231 { 232 int err; 233 uint64_t blk, off; 234 int bs = FZAP_BLOCK_SHIFT(zap); 235 dmu_buf_t *db; 236 237 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 238 ASSERT(tbl->zt_blk != 0); 239 240 dprintf("storing %llx at index %llx\n", val, idx); 241 242 blk = idx >> (bs-3); 243 off = idx & ((1<<(bs-3))-1); 244 245 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 246 (tbl->zt_blk + blk) << bs, FTAG, &db); 247 if (err) 248 return (err); 249 dmu_buf_will_dirty(db, tx); 250 251 if (tbl->zt_nextblk != 0) { 252 uint64_t idx2 = idx * 2; 253 uint64_t blk2 = idx2 >> (bs-3); 254 uint64_t off2 = idx2 & ((1<<(bs-3))-1); 255 dmu_buf_t *db2; 256 257 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 258 (tbl->zt_nextblk + blk2) << bs, FTAG, &db2); 259 if (err) { 260 dmu_buf_rele(db, FTAG); 261 return (err); 262 } 263 dmu_buf_will_dirty(db2, tx); 264 ((uint64_t *)db2->db_data)[off2] = val; 265 ((uint64_t *)db2->db_data)[off2+1] = val; 266 dmu_buf_rele(db2, FTAG); 267 } 268 269 ((uint64_t *)db->db_data)[off] = val; 270 dmu_buf_rele(db, FTAG); 271 272 return (0); 273 } 274 275 static int 276 zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp) 277 { 278 uint64_t blk, off; 279 int err; 280 dmu_buf_t *db; 281 int bs = FZAP_BLOCK_SHIFT(zap); 282 283 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 284 285 blk = idx >> (bs-3); 286 off = idx & ((1<<(bs-3))-1); 287 288 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 289 (tbl->zt_blk + blk) << bs, FTAG, &db); 290 if (err) 291 return (err); 292 *valp = ((uint64_t *)db->db_data)[off]; 293 dmu_buf_rele(db, FTAG); 294 295 if (tbl->zt_nextblk != 0) { 296 /* 297 * read the nextblk for the sake of i/o error checking, 298 * so that zap_table_load() will catch errors for 299 * zap_table_store. 300 */ 301 blk = (idx*2) >> (bs-3); 302 303 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 304 (tbl->zt_nextblk + blk) << bs, FTAG, &db); 305 dmu_buf_rele(db, FTAG); 306 } 307 return (err); 308 } 309 310 /* 311 * Routines for growing the ptrtbl. 312 */ 313 314 static void 315 zap_ptrtbl_transfer(const uint64_t *src, uint64_t *dst, int n) 316 { 317 int i; 318 for (i = 0; i < n; i++) { 319 uint64_t lb = src[i]; 320 dst[2*i+0] = lb; 321 dst[2*i+1] = lb; 322 } 323 } 324 325 static void 326 zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx) 327 { 328 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift == 32) 329 return; 330 331 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 332 /* 333 * We are outgrowing the "embedded" ptrtbl (the one 334 * stored in the header block). Give it its own entire 335 * block, which will double the size of the ptrtbl. 336 */ 337 uint64_t newblk; 338 dmu_buf_t *db_new; 339 int err; 340 341 ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==, 342 ZAP_EMBEDDED_PTRTBL_SHIFT(zap)); 343 ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_blk, ==, 0); 344 345 newblk = zap_allocate_blocks(zap, 1, tx); 346 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 347 newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new); 348 if (err) 349 return; 350 dmu_buf_will_dirty(db_new, tx); 351 zap_ptrtbl_transfer(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), 352 db_new->db_data, 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap)); 353 dmu_buf_rele(db_new, FTAG); 354 355 zap->zap_f.zap_phys->zap_ptrtbl.zt_blk = newblk; 356 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks = 1; 357 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift++; 358 359 ASSERT3U(1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==, 360 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks << 361 (FZAP_BLOCK_SHIFT(zap)-3)); 362 } else { 363 zap_table_grow(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 364 zap_ptrtbl_transfer, tx); 365 } 366 } 367 368 static void 369 zap_increment_num_entries(zap_t *zap, int delta, dmu_tx_t *tx) 370 { 371 dmu_buf_will_dirty(zap->zap_dbuf, tx); 372 mutex_enter(&zap->zap_f.zap_num_entries_mtx); 373 374 ASSERT(delta > 0 || zap->zap_f.zap_phys->zap_num_entries >= -delta); 375 376 zap->zap_f.zap_phys->zap_num_entries += delta; 377 378 mutex_exit(&zap->zap_f.zap_num_entries_mtx); 379 } 380 381 uint64_t 382 zap_allocate_blocks(zap_t *zap, int nblocks, dmu_tx_t *tx) 383 { 384 uint64_t newblk; 385 ASSERT(tx != NULL); 386 if (!RW_WRITE_HELD(&zap->zap_rwlock)) { 387 dmu_buf_will_dirty(zap->zap_dbuf, tx); 388 } 389 newblk = atomic_add_64_nv(&zap->zap_f.zap_phys->zap_freeblk, nblocks) - 390 nblocks; 391 return (newblk); 392 } 393 394 395 /* 396 * This function doesn't increment zap_num_leafs because it's used to 397 * allocate a leaf chain, which doesn't count against zap_num_leafs. 398 * The directory must be held exclusively for this tx. 399 */ 400 zap_leaf_t * 401 zap_create_leaf(zap_t *zap, dmu_tx_t *tx) 402 { 403 void *winner; 404 zap_leaf_t *l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP); 405 406 ASSERT(tx != NULL); 407 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 408 /* hence we already dirtied zap->zap_dbuf */ 409 410 rw_init(&l->l_rwlock, 0, 0, 0); 411 rw_enter(&l->l_rwlock, RW_WRITER); 412 l->l_blkid = zap_allocate_blocks(zap, 1, tx); 413 l->l_next = NULL; 414 l->l_dbuf = NULL; 415 l->l_phys = NULL; 416 417 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 418 l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf)); 419 winner = dmu_buf_set_user(l->l_dbuf, l, &l->l_phys, zap_leaf_pageout); 420 ASSERT(winner == NULL); 421 dmu_buf_will_dirty(l->l_dbuf, tx); 422 423 zap_leaf_init(l); 424 425 return (l); 426 } 427 428 /* ARGSUSED */ 429 void 430 zap_destroy_leaf(zap_t *zap, zap_leaf_t *l, dmu_tx_t *tx) 431 { 432 /* uint64_t offset = l->l_blkid << ZAP_BLOCK_SHIFT; */ 433 rw_exit(&l->l_rwlock); 434 dmu_buf_rele(l->l_dbuf, NULL); 435 /* XXX there are still holds on this block, so we can't free it? */ 436 /* dmu_free_range(zap->zap_objset, zap->zap_object, */ 437 /* offset, 1<<ZAP_BLOCK_SHIFT, tx); */ 438 } 439 440 int 441 fzap_count(zap_t *zap, uint64_t *count) 442 { 443 ASSERT(!zap->zap_ismicro); 444 mutex_enter(&zap->zap_f.zap_num_entries_mtx); /* unnecessary */ 445 *count = zap->zap_f.zap_phys->zap_num_entries; 446 mutex_exit(&zap->zap_f.zap_num_entries_mtx); 447 return (0); 448 } 449 450 /* 451 * Routines for obtaining zap_leaf_t's 452 */ 453 454 void 455 zap_put_leaf(zap_leaf_t *l) 456 { 457 zap_leaf_t *nl = l->l_next; 458 while (nl) { 459 zap_leaf_t *nnl = nl->l_next; 460 rw_exit(&nl->l_rwlock); 461 dmu_buf_rele(nl->l_dbuf, NULL); 462 nl = nnl; 463 } 464 rw_exit(&l->l_rwlock); 465 dmu_buf_rele(l->l_dbuf, NULL); 466 } 467 468 _NOTE(ARGSUSED(0)) 469 static void 470 zap_leaf_pageout(dmu_buf_t *db, void *vl) 471 { 472 zap_leaf_t *l = vl; 473 474 rw_destroy(&l->l_rwlock); 475 kmem_free(l, sizeof (zap_leaf_t)); 476 } 477 478 static zap_leaf_t * 479 zap_open_leaf(uint64_t blkid, dmu_buf_t *db) 480 { 481 zap_leaf_t *l, *winner; 482 483 ASSERT(blkid != 0); 484 485 l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP); 486 rw_init(&l->l_rwlock, 0, 0, 0); 487 rw_enter(&l->l_rwlock, RW_WRITER); 488 l->l_blkid = blkid; 489 l->l_bs = highbit(db->db_size)-1; 490 l->l_next = NULL; 491 l->l_dbuf = db; 492 l->l_phys = NULL; 493 494 winner = dmu_buf_set_user(db, l, &l->l_phys, zap_leaf_pageout); 495 496 rw_exit(&l->l_rwlock); 497 if (winner != NULL) { 498 /* someone else set it first */ 499 zap_leaf_pageout(NULL, l); 500 l = winner; 501 } 502 503 /* 504 * There should be more hash entries than there can be 505 * chunks to put in the hash table 506 */ 507 ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3); 508 509 /* The chunks should begin at the end of the hash table */ 510 ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==, 511 &l->l_phys->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]); 512 513 /* The chunks should end at the end of the block */ 514 ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) - 515 (uintptr_t)l->l_phys, ==, l->l_dbuf->db_size); 516 517 return (l); 518 } 519 520 static int 521 zap_get_leaf_byblk_impl(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt, 522 zap_leaf_t **lp) 523 { 524 dmu_buf_t *db; 525 zap_leaf_t *l; 526 int bs = FZAP_BLOCK_SHIFT(zap); 527 int err; 528 529 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 530 531 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 532 blkid << bs, NULL, &db); 533 if (err) 534 return (err); 535 536 ASSERT3U(db->db_object, ==, zap->zap_object); 537 ASSERT3U(db->db_offset, ==, blkid << bs); 538 ASSERT3U(db->db_size, ==, 1 << bs); 539 ASSERT(blkid != 0); 540 541 l = dmu_buf_get_user(db); 542 543 if (l == NULL) 544 l = zap_open_leaf(blkid, db); 545 546 rw_enter(&l->l_rwlock, lt); 547 /* 548 * Must lock before dirtying, otherwise l->l_phys could change, 549 * causing ASSERT below to fail. 550 */ 551 if (lt == RW_WRITER) 552 dmu_buf_will_dirty(db, tx); 553 ASSERT3U(l->l_blkid, ==, blkid); 554 ASSERT3P(l->l_dbuf, ==, db); 555 ASSERT3P(l->l_phys, ==, l->l_dbuf->db_data); 556 ASSERT3U(l->lh_block_type, ==, ZBT_LEAF); 557 ASSERT3U(l->lh_magic, ==, ZAP_LEAF_MAGIC); 558 559 *lp = l; 560 return (0); 561 } 562 563 static int 564 zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt, 565 zap_leaf_t **lp) 566 { 567 int err; 568 zap_leaf_t *nl; 569 570 err = zap_get_leaf_byblk_impl(zap, blkid, tx, lt, lp); 571 if (err) 572 return (err); 573 574 nl = *lp; 575 while (nl->lh_next != 0) { 576 zap_leaf_t *nnl; 577 err = zap_get_leaf_byblk_impl(zap, nl->lh_next, tx, lt, &nnl); 578 if (err) { 579 zap_put_leaf(*lp); 580 return (err); 581 } 582 nl->l_next = nnl; 583 nl = nnl; 584 } 585 586 return (err); 587 } 588 589 static int 590 zap_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t *valp) 591 { 592 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 593 594 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 595 ASSERT3U(idx, <, 596 (1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift)); 597 *valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx); 598 return (0); 599 } else { 600 return (zap_table_load(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 601 idx, valp)); 602 } 603 } 604 605 static int 606 zap_set_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t blk, dmu_tx_t *tx) 607 { 608 ASSERT(tx != NULL); 609 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 610 611 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0) { 612 ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk; 613 return (0); 614 } else { 615 return (zap_table_store(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 616 idx, blk, tx)); 617 } 618 } 619 620 static int 621 zap_deref_leaf(zap_t *zap, uint64_t h, dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp) 622 { 623 uint64_t idx, blk; 624 int err; 625 626 ASSERT(zap->zap_dbuf == NULL || 627 zap->zap_f.zap_phys == zap->zap_dbuf->db_data); 628 ASSERT3U(zap->zap_f.zap_phys->zap_magic, ==, ZAP_MAGIC); 629 idx = ZAP_HASH_IDX(h, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 630 err = zap_idx_to_blk(zap, idx, &blk); 631 if (err != 0) 632 return (err); 633 err = zap_get_leaf_byblk(zap, blk, tx, lt, lp); 634 635 ASSERT(err || 636 ZAP_HASH_IDX(h, (*lp)->lh_prefix_len) == (*lp)->lh_prefix); 637 return (err); 638 } 639 640 641 static int 642 zap_expand_leaf(zap_t *zap, zap_leaf_t *l, uint64_t hash, dmu_tx_t *tx, 643 zap_leaf_t **lp) 644 { 645 zap_leaf_t *nl; 646 int prefix_diff, i, err; 647 uint64_t sibling; 648 649 ASSERT3U(l->lh_prefix_len, <=, 650 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 651 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 652 653 ASSERT3U(ZAP_HASH_IDX(hash, l->lh_prefix_len), ==, l->lh_prefix); 654 655 if (zap_tryupgradedir(zap, tx) == 0) { 656 /* failed to upgrade */ 657 int old_prefix_len = l->lh_prefix_len; 658 objset_t *os = zap->zap_objset; 659 uint64_t object = zap->zap_object; 660 661 zap_put_leaf(l); 662 zap_unlockdir(zap); 663 err = zap_lockdir(os, object, tx, RW_WRITER, FALSE, &zap); 664 ASSERT3U(err, ==, 0); 665 ASSERT(!zap->zap_ismicro); 666 (void) zap_deref_leaf(zap, hash, tx, RW_WRITER, &l); 667 668 if (l->lh_prefix_len != old_prefix_len) { 669 /* it split while our locks were down */ 670 *lp = l; 671 return (0); 672 } 673 } 674 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 675 676 if (l->lh_prefix_len == zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) { 677 /* There's only one pointer to us. Chain on another leaf blk. */ 678 (void) zap_leaf_chainmore(l, zap_create_leaf(zap, tx)); 679 dprintf("chaining leaf %x/%d\n", l->lh_prefix, 680 l->lh_prefix_len); 681 *lp = l; 682 return (0); 683 } 684 685 ASSERT3U(ZAP_HASH_IDX(hash, l->lh_prefix_len), ==, l->lh_prefix); 686 687 /* There's more than one pointer to us. Split this leaf. */ 688 689 /* set sibling pointers */ 690 prefix_diff = 691 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift - (l->lh_prefix_len + 1); 692 sibling = (ZAP_HASH_IDX(hash, l->lh_prefix_len + 1) | 1) << prefix_diff; 693 694 /* check for i/o errors before doing zap_leaf_split */ 695 for (i = 0; i < (1ULL<<prefix_diff); i++) { 696 uint64_t blk; 697 err = zap_idx_to_blk(zap, sibling+i, &blk); 698 if (err) 699 return (err); 700 ASSERT3U(blk, ==, l->l_blkid); 701 } 702 703 nl = zap_leaf_split(zap, l, tx); 704 705 for (i = 0; i < (1ULL<<prefix_diff); i++) { 706 err = zap_set_idx_to_blk(zap, sibling+i, nl->l_blkid, tx); 707 ASSERT3U(err, ==, 0); /* we checked for i/o errors above */ 708 /* dprintf("set %d to %u %x\n", sibling+i, nl->l_blkid, nl); */ 709 } 710 711 zap->zap_f.zap_phys->zap_num_leafs++; 712 713 if (hash & (1ULL << (64 - l->lh_prefix_len))) { 714 /* we want the sibling */ 715 zap_put_leaf(l); 716 l = nl; 717 } else { 718 zap_put_leaf(nl); 719 } 720 721 *lp = l; 722 return (0); 723 } 724 725 static void 726 zap_put_leaf_maybe_grow_ptrtbl(zap_t *zap, zap_leaf_t *l, dmu_tx_t *tx) 727 { 728 int shift, err; 729 730 again: 731 shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift; 732 733 if (l->lh_prefix_len == shift && 734 (l->l_next != NULL || l->lh_nfree < MIN_FREE(l))) { 735 /* this leaf will soon make us grow the pointer table */ 736 737 if (zap_tryupgradedir(zap, tx) == 0) { 738 objset_t *os = zap->zap_objset; 739 uint64_t zapobj = zap->zap_object; 740 uint64_t blkid = l->l_blkid; 741 742 zap_put_leaf(l); 743 zap_unlockdir(zap); 744 err = zap_lockdir(os, zapobj, tx, 745 RW_WRITER, FALSE, &zap); 746 ASSERT3U(err, ==, 0); 747 (void) zap_get_leaf_byblk(zap, blkid, tx, 748 RW_READER, &l); 749 goto again; 750 } 751 752 zap_put_leaf(l); 753 zap_grow_ptrtbl(zap, tx); 754 } else { 755 zap_put_leaf(l); 756 } 757 } 758 759 760 static int 761 fzap_checksize(uint64_t integer_size, uint64_t num_integers) 762 { 763 /* Only integer sizes supported by C */ 764 switch (integer_size) { 765 case 1: 766 case 2: 767 case 4: 768 case 8: 769 break; 770 default: 771 return (EINVAL); 772 } 773 774 /* Make sure we won't overflow */ 775 if (integer_size * num_integers < num_integers) 776 return (EINVAL); 777 if (integer_size * num_integers > (1<<fzap_default_block_shift)) 778 return (EINVAL); 779 780 return (0); 781 } 782 783 /* 784 * Routines for maniplulating attributes. 785 */ 786 int 787 fzap_lookup(zap_t *zap, const char *name, 788 uint64_t integer_size, uint64_t num_integers, void *buf) 789 { 790 zap_leaf_t *l; 791 int err; 792 uint64_t hash; 793 zap_entry_handle_t zeh; 794 795 err = fzap_checksize(integer_size, num_integers); 796 if (err != 0) 797 return (err); 798 799 hash = zap_hash(zap, name); 800 err = zap_deref_leaf(zap, hash, NULL, RW_READER, &l); 801 if (err != 0) 802 return (err); 803 err = zap_leaf_lookup(l, name, hash, &zeh); 804 if (err != 0) 805 goto out; 806 err = zap_entry_read(&zeh, integer_size, num_integers, buf); 807 out: 808 zap_put_leaf(l); 809 return (err); 810 } 811 812 int 813 fzap_add_cd(zap_t *zap, const char *name, 814 uint64_t integer_size, uint64_t num_integers, 815 const void *val, uint32_t cd, dmu_tx_t *tx) 816 { 817 zap_leaf_t *l; 818 uint64_t hash; 819 int err; 820 zap_entry_handle_t zeh; 821 822 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 823 ASSERT(!zap->zap_ismicro); 824 ASSERT(fzap_checksize(integer_size, num_integers) == 0); 825 826 hash = zap_hash(zap, name); 827 err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l); 828 if (err != 0) 829 return (err); 830 retry: 831 err = zap_leaf_lookup(l, name, hash, &zeh); 832 if (err == 0) { 833 err = EEXIST; 834 goto out; 835 } 836 if (err != ENOENT) 837 goto out; 838 839 /* XXX If this leaf is chained, split it if we can. */ 840 err = zap_entry_create(l, name, hash, cd, 841 integer_size, num_integers, val, &zeh); 842 843 if (err == 0) { 844 zap_increment_num_entries(zap, 1, tx); 845 } else if (err == EAGAIN) { 846 err = zap_expand_leaf(zap, l, hash, tx, &l); 847 if (err != 0) 848 goto out; 849 goto retry; 850 } 851 852 out: 853 zap_put_leaf_maybe_grow_ptrtbl(zap, l, tx); 854 return (err); 855 } 856 857 int 858 fzap_add(zap_t *zap, const char *name, 859 uint64_t integer_size, uint64_t num_integers, 860 const void *val, dmu_tx_t *tx) 861 { 862 int err; 863 864 err = fzap_checksize(integer_size, num_integers); 865 if (err != 0) 866 return (err); 867 868 err = fzap_add_cd(zap, name, integer_size, num_integers, 869 val, ZAP_MAXCD, tx); 870 871 return (err); 872 } 873 874 int 875 fzap_update(zap_t *zap, const char *name, 876 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx) 877 { 878 zap_leaf_t *l; 879 uint64_t hash; 880 int err, create; 881 zap_entry_handle_t zeh; 882 883 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 884 err = fzap_checksize(integer_size, num_integers); 885 if (err != 0) 886 return (err); 887 888 hash = zap_hash(zap, name); 889 err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l); 890 if (err != 0) 891 return (err); 892 retry: 893 err = zap_leaf_lookup(l, name, hash, &zeh); 894 create = (err == ENOENT); 895 ASSERT(err == 0 || err == ENOENT); 896 897 /* XXX If this leaf is chained, split it if we can. */ 898 899 if (create) { 900 err = zap_entry_create(l, name, hash, ZAP_MAXCD, 901 integer_size, num_integers, val, &zeh); 902 if (err == 0) 903 zap_increment_num_entries(zap, 1, tx); 904 } else { 905 err = zap_entry_update(&zeh, integer_size, num_integers, val); 906 } 907 908 if (err == EAGAIN) { 909 err = zap_expand_leaf(zap, l, hash, tx, &l); 910 if (err != 0) 911 goto out; 912 goto retry; 913 } 914 915 out: 916 zap_put_leaf_maybe_grow_ptrtbl(zap, l, tx); 917 return (err); 918 } 919 920 int 921 fzap_length(zap_t *zap, const char *name, 922 uint64_t *integer_size, uint64_t *num_integers) 923 { 924 zap_leaf_t *l; 925 int err; 926 uint64_t hash; 927 zap_entry_handle_t zeh; 928 929 hash = zap_hash(zap, name); 930 err = zap_deref_leaf(zap, hash, NULL, RW_READER, &l); 931 if (err != 0) 932 return (err); 933 err = zap_leaf_lookup(l, name, hash, &zeh); 934 if (err != 0) 935 goto out; 936 937 if (integer_size) 938 *integer_size = zeh.zeh_integer_size; 939 if (num_integers) 940 *num_integers = zeh.zeh_num_integers; 941 out: 942 zap_put_leaf(l); 943 return (err); 944 } 945 946 int 947 fzap_remove(zap_t *zap, const char *name, dmu_tx_t *tx) 948 { 949 zap_leaf_t *l; 950 uint64_t hash; 951 int err; 952 zap_entry_handle_t zeh; 953 954 hash = zap_hash(zap, name); 955 err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l); 956 if (err != 0) 957 return (err); 958 err = zap_leaf_lookup(l, name, hash, &zeh); 959 if (err == 0) { 960 zap_entry_remove(&zeh); 961 zap_increment_num_entries(zap, -1, tx); 962 } 963 zap_put_leaf(l); 964 dprintf("fzap_remove: ds=%p obj=%llu name=%s err=%d\n", 965 zap->zap_objset, zap->zap_object, name, err); 966 return (err); 967 } 968 969 int 970 zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, char *name) 971 { 972 zap_cursor_t zc; 973 zap_attribute_t *za; 974 int err; 975 976 za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP); 977 for (zap_cursor_init(&zc, os, zapobj); 978 (err = zap_cursor_retrieve(&zc, za)) == 0; 979 zap_cursor_advance(&zc)) { 980 if (za->za_first_integer == value) { 981 (void) strcpy(name, za->za_name); 982 break; 983 } 984 } 985 zap_cursor_fini(&zc); 986 kmem_free(za, sizeof (zap_attribute_t)); 987 return (err); 988 } 989 990 991 /* 992 * Routines for iterating over the attributes. 993 */ 994 995 int 996 fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za) 997 { 998 int err = ENOENT; 999 zap_entry_handle_t zeh; 1000 zap_leaf_t *l; 1001 1002 /* retrieve the next entry at or after zc_hash/zc_cd */ 1003 /* if no entry, return ENOENT */ 1004 1005 if (zc->zc_leaf && 1006 (ZAP_HASH_IDX(zc->zc_hash, zc->zc_leaf->lh_prefix_len) != 1007 zc->zc_leaf->lh_prefix)) { 1008 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); 1009 zap_put_leaf(zc->zc_leaf); 1010 zc->zc_leaf = NULL; 1011 } 1012 1013 again: 1014 if (zc->zc_leaf == NULL) { 1015 err = zap_deref_leaf(zap, zc->zc_hash, NULL, RW_READER, 1016 &zc->zc_leaf); 1017 if (err != 0) 1018 return (err); 1019 } else { 1020 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); 1021 } 1022 l = zc->zc_leaf; 1023 1024 err = zap_leaf_lookup_closest(l, zc->zc_hash, zc->zc_cd, &zeh); 1025 1026 if (err == ENOENT) { 1027 uint64_t nocare = (1ULL << (64 - l->lh_prefix_len)) - 1; 1028 zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1; 1029 zc->zc_cd = 0; 1030 if (l->lh_prefix_len == 0 || zc->zc_hash == 0) { 1031 zc->zc_hash = -1ULL; 1032 } else { 1033 zap_put_leaf(zc->zc_leaf); 1034 zc->zc_leaf = NULL; 1035 goto again; 1036 } 1037 } 1038 1039 if (err == 0) { 1040 zc->zc_hash = zeh.zeh_hash; 1041 zc->zc_cd = zeh.zeh_cd; 1042 za->za_integer_length = zeh.zeh_integer_size; 1043 za->za_num_integers = zeh.zeh_num_integers; 1044 if (zeh.zeh_num_integers == 0) { 1045 za->za_first_integer = 0; 1046 } else { 1047 err = zap_entry_read(&zeh, 8, 1, &za->za_first_integer); 1048 ASSERT(err == 0 || err == EOVERFLOW); 1049 } 1050 err = zap_entry_read_name(&zeh, 1051 sizeof (za->za_name), za->za_name); 1052 ASSERT(err == 0); 1053 } 1054 rw_exit(&zc->zc_leaf->l_rwlock); 1055 return (err); 1056 } 1057 1058 1059 static void 1060 zap_stats_ptrtbl(zap_t *zap, uint64_t *tbl, int len, zap_stats_t *zs) 1061 { 1062 int i, err; 1063 uint64_t lastblk = 0; 1064 1065 /* 1066 * NB: if a leaf has more pointers than an entire ptrtbl block 1067 * can hold, then it'll be accounted for more than once, since 1068 * we won't have lastblk. 1069 */ 1070 for (i = 0; i < len; i++) { 1071 zap_leaf_t *l; 1072 1073 if (tbl[i] == lastblk) 1074 continue; 1075 lastblk = tbl[i]; 1076 1077 err = zap_get_leaf_byblk(zap, tbl[i], NULL, RW_READER, &l); 1078 if (err == 0) { 1079 zap_stats_leaf(zap, l, zs); 1080 zap_put_leaf(l); 1081 } 1082 } 1083 } 1084 1085 void 1086 fzap_get_stats(zap_t *zap, zap_stats_t *zs) 1087 { 1088 int bs = FZAP_BLOCK_SHIFT(zap); 1089 zs->zs_ptrtbl_len = 1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift; 1090 zs->zs_blocksize = 1ULL << bs; 1091 zs->zs_num_leafs = zap->zap_f.zap_phys->zap_num_leafs; 1092 zs->zs_num_entries = zap->zap_f.zap_phys->zap_num_entries; 1093 zs->zs_num_blocks = zap->zap_f.zap_phys->zap_freeblk; 1094 1095 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 1096 /* the ptrtbl is entirely in the header block. */ 1097 zap_stats_ptrtbl(zap, &ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), 1098 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap), zs); 1099 } else { 1100 int b; 1101 1102 dmu_prefetch(zap->zap_objset, zap->zap_object, 1103 zap->zap_f.zap_phys->zap_ptrtbl.zt_blk << bs, 1104 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks << bs); 1105 1106 for (b = 0; b < zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks; 1107 b++) { 1108 dmu_buf_t *db; 1109 int err; 1110 1111 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 1112 (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk + b) << bs, 1113 FTAG, &db); 1114 if (err == 0) { 1115 zap_stats_ptrtbl(zap, db->db_data, 1116 1<<(bs-3), zs); 1117 dmu_buf_rele(db, FTAG); 1118 } 1119 } 1120 } 1121 } 1122