1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2013 by Delphix. All rights reserved. 24 */ 25 26 /* 27 * This file contains the top half of the zfs directory structure 28 * implementation. The bottom half is in zap_leaf.c. 29 * 30 * The zdir is an extendable hash data structure. There is a table of 31 * pointers to buckets (zap_t->zd_data->zd_leafs). The buckets are 32 * each a constant size and hold a variable number of directory entries. 33 * The buckets (aka "leaf nodes") are implemented in zap_leaf.c. 34 * 35 * The pointer table holds a power of 2 number of pointers. 36 * (1<<zap_t->zd_data->zd_phys->zd_prefix_len). The bucket pointed to 37 * by the pointer at index i in the table holds entries whose hash value 38 * has a zd_prefix_len - bit prefix 39 */ 40 41 #include <sys/spa.h> 42 #include <sys/dmu.h> 43 #include <sys/zfs_context.h> 44 #include <sys/zfs_znode.h> 45 #include <sys/fs/zfs.h> 46 #include <sys/zap.h> 47 #include <sys/refcount.h> 48 #include <sys/zap_impl.h> 49 #include <sys/zap_leaf.h> 50 51 int fzap_default_block_shift = 14; /* 16k blocksize */ 52 53 static void zap_leaf_pageout(dmu_buf_t *db, void *vl); 54 static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks); 55 56 57 void 58 fzap_byteswap(void *vbuf, size_t size) 59 { 60 uint64_t block_type; 61 62 block_type = *(uint64_t *)vbuf; 63 64 if (block_type == ZBT_LEAF || block_type == BSWAP_64(ZBT_LEAF)) 65 zap_leaf_byteswap(vbuf, size); 66 else { 67 /* it's a ptrtbl block */ 68 byteswap_uint64_array(vbuf, size); 69 } 70 } 71 72 void 73 fzap_upgrade(zap_t *zap, dmu_tx_t *tx, zap_flags_t flags) 74 { 75 dmu_buf_t *db; 76 zap_leaf_t *l; 77 int i; 78 zap_phys_t *zp; 79 80 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 81 zap->zap_ismicro = FALSE; 82 83 (void) dmu_buf_update_user(zap->zap_dbuf, zap, zap, 84 &zap->zap_f.zap_phys, zap_evict); 85 86 mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0); 87 zap->zap_f.zap_block_shift = highbit(zap->zap_dbuf->db_size) - 1; 88 89 zp = zap->zap_f.zap_phys; 90 /* 91 * explicitly zero it since it might be coming from an 92 * initialized microzap 93 */ 94 bzero(zap->zap_dbuf->db_data, zap->zap_dbuf->db_size); 95 zp->zap_block_type = ZBT_HEADER; 96 zp->zap_magic = ZAP_MAGIC; 97 98 zp->zap_ptrtbl.zt_shift = ZAP_EMBEDDED_PTRTBL_SHIFT(zap); 99 100 zp->zap_freeblk = 2; /* block 1 will be the first leaf */ 101 zp->zap_num_leafs = 1; 102 zp->zap_num_entries = 0; 103 zp->zap_salt = zap->zap_salt; 104 zp->zap_normflags = zap->zap_normflags; 105 zp->zap_flags = flags; 106 107 /* block 1 will be the first leaf */ 108 for (i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++) 109 ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1; 110 111 /* 112 * set up block 1 - the first leaf 113 */ 114 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 115 1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db, DMU_READ_NO_PREFETCH)); 116 dmu_buf_will_dirty(db, tx); 117 118 l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP); 119 l->l_dbuf = db; 120 l->l_phys = db->db_data; 121 122 zap_leaf_init(l, zp->zap_normflags != 0); 123 124 kmem_free(l, sizeof (zap_leaf_t)); 125 dmu_buf_rele(db, FTAG); 126 } 127 128 static int 129 zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx) 130 { 131 if (RW_WRITE_HELD(&zap->zap_rwlock)) 132 return (1); 133 if (rw_tryupgrade(&zap->zap_rwlock)) { 134 dmu_buf_will_dirty(zap->zap_dbuf, tx); 135 return (1); 136 } 137 return (0); 138 } 139 140 /* 141 * Generic routines for dealing with the pointer & cookie tables. 142 */ 143 144 static int 145 zap_table_grow(zap_t *zap, zap_table_phys_t *tbl, 146 void (*transfer_func)(const uint64_t *src, uint64_t *dst, int n), 147 dmu_tx_t *tx) 148 { 149 uint64_t b, newblk; 150 dmu_buf_t *db_old, *db_new; 151 int err; 152 int bs = FZAP_BLOCK_SHIFT(zap); 153 int hepb = 1<<(bs-4); 154 /* hepb = half the number of entries in a block */ 155 156 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 157 ASSERT(tbl->zt_blk != 0); 158 ASSERT(tbl->zt_numblks > 0); 159 160 if (tbl->zt_nextblk != 0) { 161 newblk = tbl->zt_nextblk; 162 } else { 163 newblk = zap_allocate_blocks(zap, tbl->zt_numblks * 2); 164 tbl->zt_nextblk = newblk; 165 ASSERT0(tbl->zt_blks_copied); 166 dmu_prefetch(zap->zap_objset, zap->zap_object, 167 tbl->zt_blk << bs, tbl->zt_numblks << bs); 168 } 169 170 /* 171 * Copy the ptrtbl from the old to new location. 172 */ 173 174 b = tbl->zt_blks_copied; 175 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 176 (tbl->zt_blk + b) << bs, FTAG, &db_old, DMU_READ_NO_PREFETCH); 177 if (err) 178 return (err); 179 180 /* first half of entries in old[b] go to new[2*b+0] */ 181 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 182 (newblk + 2*b+0) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH)); 183 dmu_buf_will_dirty(db_new, tx); 184 transfer_func(db_old->db_data, db_new->db_data, hepb); 185 dmu_buf_rele(db_new, FTAG); 186 187 /* second half of entries in old[b] go to new[2*b+1] */ 188 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 189 (newblk + 2*b+1) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH)); 190 dmu_buf_will_dirty(db_new, tx); 191 transfer_func((uint64_t *)db_old->db_data + hepb, 192 db_new->db_data, hepb); 193 dmu_buf_rele(db_new, FTAG); 194 195 dmu_buf_rele(db_old, FTAG); 196 197 tbl->zt_blks_copied++; 198 199 dprintf("copied block %llu of %llu\n", 200 tbl->zt_blks_copied, tbl->zt_numblks); 201 202 if (tbl->zt_blks_copied == tbl->zt_numblks) { 203 (void) dmu_free_range(zap->zap_objset, zap->zap_object, 204 tbl->zt_blk << bs, tbl->zt_numblks << bs, tx); 205 206 tbl->zt_blk = newblk; 207 tbl->zt_numblks *= 2; 208 tbl->zt_shift++; 209 tbl->zt_nextblk = 0; 210 tbl->zt_blks_copied = 0; 211 212 dprintf("finished; numblocks now %llu (%lluk entries)\n", 213 tbl->zt_numblks, 1<<(tbl->zt_shift-10)); 214 } 215 216 return (0); 217 } 218 219 static int 220 zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val, 221 dmu_tx_t *tx) 222 { 223 int err; 224 uint64_t blk, off; 225 int bs = FZAP_BLOCK_SHIFT(zap); 226 dmu_buf_t *db; 227 228 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 229 ASSERT(tbl->zt_blk != 0); 230 231 dprintf("storing %llx at index %llx\n", val, idx); 232 233 blk = idx >> (bs-3); 234 off = idx & ((1<<(bs-3))-1); 235 236 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 237 (tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH); 238 if (err) 239 return (err); 240 dmu_buf_will_dirty(db, tx); 241 242 if (tbl->zt_nextblk != 0) { 243 uint64_t idx2 = idx * 2; 244 uint64_t blk2 = idx2 >> (bs-3); 245 uint64_t off2 = idx2 & ((1<<(bs-3))-1); 246 dmu_buf_t *db2; 247 248 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 249 (tbl->zt_nextblk + blk2) << bs, FTAG, &db2, 250 DMU_READ_NO_PREFETCH); 251 if (err) { 252 dmu_buf_rele(db, FTAG); 253 return (err); 254 } 255 dmu_buf_will_dirty(db2, tx); 256 ((uint64_t *)db2->db_data)[off2] = val; 257 ((uint64_t *)db2->db_data)[off2+1] = val; 258 dmu_buf_rele(db2, FTAG); 259 } 260 261 ((uint64_t *)db->db_data)[off] = val; 262 dmu_buf_rele(db, FTAG); 263 264 return (0); 265 } 266 267 static int 268 zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp) 269 { 270 uint64_t blk, off; 271 int err; 272 dmu_buf_t *db; 273 int bs = FZAP_BLOCK_SHIFT(zap); 274 275 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 276 277 blk = idx >> (bs-3); 278 off = idx & ((1<<(bs-3))-1); 279 280 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 281 (tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH); 282 if (err) 283 return (err); 284 *valp = ((uint64_t *)db->db_data)[off]; 285 dmu_buf_rele(db, FTAG); 286 287 if (tbl->zt_nextblk != 0) { 288 /* 289 * read the nextblk for the sake of i/o error checking, 290 * so that zap_table_load() will catch errors for 291 * zap_table_store. 292 */ 293 blk = (idx*2) >> (bs-3); 294 295 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 296 (tbl->zt_nextblk + blk) << bs, FTAG, &db, 297 DMU_READ_NO_PREFETCH); 298 dmu_buf_rele(db, FTAG); 299 } 300 return (err); 301 } 302 303 /* 304 * Routines for growing the ptrtbl. 305 */ 306 307 static void 308 zap_ptrtbl_transfer(const uint64_t *src, uint64_t *dst, int n) 309 { 310 int i; 311 for (i = 0; i < n; i++) { 312 uint64_t lb = src[i]; 313 dst[2*i+0] = lb; 314 dst[2*i+1] = lb; 315 } 316 } 317 318 static int 319 zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx) 320 { 321 /* 322 * The pointer table should never use more hash bits than we 323 * have (otherwise we'd be using useless zero bits to index it). 324 * If we are within 2 bits of running out, stop growing, since 325 * this is already an aberrant condition. 326 */ 327 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift >= zap_hashbits(zap) - 2) 328 return (SET_ERROR(ENOSPC)); 329 330 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 331 /* 332 * We are outgrowing the "embedded" ptrtbl (the one 333 * stored in the header block). Give it its own entire 334 * block, which will double the size of the ptrtbl. 335 */ 336 uint64_t newblk; 337 dmu_buf_t *db_new; 338 int err; 339 340 ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==, 341 ZAP_EMBEDDED_PTRTBL_SHIFT(zap)); 342 ASSERT0(zap->zap_f.zap_phys->zap_ptrtbl.zt_blk); 343 344 newblk = zap_allocate_blocks(zap, 1); 345 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 346 newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new, 347 DMU_READ_NO_PREFETCH); 348 if (err) 349 return (err); 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)); 362 363 return (0); 364 } else { 365 return (zap_table_grow(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 366 zap_ptrtbl_transfer, tx)); 367 } 368 } 369 370 static void 371 zap_increment_num_entries(zap_t *zap, int delta, dmu_tx_t *tx) 372 { 373 dmu_buf_will_dirty(zap->zap_dbuf, tx); 374 mutex_enter(&zap->zap_f.zap_num_entries_mtx); 375 ASSERT(delta > 0 || zap->zap_f.zap_phys->zap_num_entries >= -delta); 376 zap->zap_f.zap_phys->zap_num_entries += delta; 377 mutex_exit(&zap->zap_f.zap_num_entries_mtx); 378 } 379 380 static uint64_t 381 zap_allocate_blocks(zap_t *zap, int nblocks) 382 { 383 uint64_t newblk; 384 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 385 newblk = zap->zap_f.zap_phys->zap_freeblk; 386 zap->zap_f.zap_phys->zap_freeblk += nblocks; 387 return (newblk); 388 } 389 390 static zap_leaf_t * 391 zap_create_leaf(zap_t *zap, dmu_tx_t *tx) 392 { 393 void *winner; 394 zap_leaf_t *l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP); 395 396 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 397 398 rw_init(&l->l_rwlock, 0, 0, 0); 399 rw_enter(&l->l_rwlock, RW_WRITER); 400 l->l_blkid = zap_allocate_blocks(zap, 1); 401 l->l_dbuf = NULL; 402 l->l_phys = NULL; 403 404 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object, 405 l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf, 406 DMU_READ_NO_PREFETCH)); 407 winner = dmu_buf_set_user(l->l_dbuf, l, &l->l_phys, zap_leaf_pageout); 408 ASSERT(winner == NULL); 409 dmu_buf_will_dirty(l->l_dbuf, tx); 410 411 zap_leaf_init(l, zap->zap_normflags != 0); 412 413 zap->zap_f.zap_phys->zap_num_leafs++; 414 415 return (l); 416 } 417 418 int 419 fzap_count(zap_t *zap, uint64_t *count) 420 { 421 ASSERT(!zap->zap_ismicro); 422 mutex_enter(&zap->zap_f.zap_num_entries_mtx); /* unnecessary */ 423 *count = zap->zap_f.zap_phys->zap_num_entries; 424 mutex_exit(&zap->zap_f.zap_num_entries_mtx); 425 return (0); 426 } 427 428 /* 429 * Routines for obtaining zap_leaf_t's 430 */ 431 432 void 433 zap_put_leaf(zap_leaf_t *l) 434 { 435 rw_exit(&l->l_rwlock); 436 dmu_buf_rele(l->l_dbuf, NULL); 437 } 438 439 _NOTE(ARGSUSED(0)) 440 static void 441 zap_leaf_pageout(dmu_buf_t *db, void *vl) 442 { 443 zap_leaf_t *l = vl; 444 445 rw_destroy(&l->l_rwlock); 446 kmem_free(l, sizeof (zap_leaf_t)); 447 } 448 449 static zap_leaf_t * 450 zap_open_leaf(uint64_t blkid, dmu_buf_t *db) 451 { 452 zap_leaf_t *l, *winner; 453 454 ASSERT(blkid != 0); 455 456 l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP); 457 rw_init(&l->l_rwlock, 0, 0, 0); 458 rw_enter(&l->l_rwlock, RW_WRITER); 459 l->l_blkid = blkid; 460 l->l_bs = highbit(db->db_size)-1; 461 l->l_dbuf = db; 462 l->l_phys = NULL; 463 464 winner = dmu_buf_set_user(db, l, &l->l_phys, zap_leaf_pageout); 465 466 rw_exit(&l->l_rwlock); 467 if (winner != NULL) { 468 /* someone else set it first */ 469 zap_leaf_pageout(NULL, l); 470 l = winner; 471 } 472 473 /* 474 * lhr_pad was previously used for the next leaf in the leaf 475 * chain. There should be no chained leafs (as we have removed 476 * support for them). 477 */ 478 ASSERT0(l->l_phys->l_hdr.lh_pad1); 479 480 /* 481 * There should be more hash entries than there can be 482 * chunks to put in the hash table 483 */ 484 ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3); 485 486 /* The chunks should begin at the end of the hash table */ 487 ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==, 488 &l->l_phys->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]); 489 490 /* The chunks should end at the end of the block */ 491 ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) - 492 (uintptr_t)l->l_phys, ==, l->l_dbuf->db_size); 493 494 return (l); 495 } 496 497 static int 498 zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt, 499 zap_leaf_t **lp) 500 { 501 dmu_buf_t *db; 502 zap_leaf_t *l; 503 int bs = FZAP_BLOCK_SHIFT(zap); 504 int err; 505 506 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 507 508 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 509 blkid << bs, NULL, &db, DMU_READ_NO_PREFETCH); 510 if (err) 511 return (err); 512 513 ASSERT3U(db->db_object, ==, zap->zap_object); 514 ASSERT3U(db->db_offset, ==, blkid << bs); 515 ASSERT3U(db->db_size, ==, 1 << bs); 516 ASSERT(blkid != 0); 517 518 l = dmu_buf_get_user(db); 519 520 if (l == NULL) 521 l = zap_open_leaf(blkid, db); 522 523 rw_enter(&l->l_rwlock, lt); 524 /* 525 * Must lock before dirtying, otherwise l->l_phys could change, 526 * causing ASSERT below to fail. 527 */ 528 if (lt == RW_WRITER) 529 dmu_buf_will_dirty(db, tx); 530 ASSERT3U(l->l_blkid, ==, blkid); 531 ASSERT3P(l->l_dbuf, ==, db); 532 ASSERT3P(l->l_phys, ==, l->l_dbuf->db_data); 533 ASSERT3U(l->l_phys->l_hdr.lh_block_type, ==, ZBT_LEAF); 534 ASSERT3U(l->l_phys->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC); 535 536 *lp = l; 537 return (0); 538 } 539 540 static int 541 zap_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t *valp) 542 { 543 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 544 545 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 546 ASSERT3U(idx, <, 547 (1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift)); 548 *valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx); 549 return (0); 550 } else { 551 return (zap_table_load(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 552 idx, valp)); 553 } 554 } 555 556 static int 557 zap_set_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t blk, dmu_tx_t *tx) 558 { 559 ASSERT(tx != NULL); 560 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 561 562 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0) { 563 ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk; 564 return (0); 565 } else { 566 return (zap_table_store(zap, &zap->zap_f.zap_phys->zap_ptrtbl, 567 idx, blk, tx)); 568 } 569 } 570 571 static int 572 zap_deref_leaf(zap_t *zap, uint64_t h, dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp) 573 { 574 uint64_t idx, blk; 575 int err; 576 577 ASSERT(zap->zap_dbuf == NULL || 578 zap->zap_f.zap_phys == zap->zap_dbuf->db_data); 579 ASSERT3U(zap->zap_f.zap_phys->zap_magic, ==, ZAP_MAGIC); 580 idx = ZAP_HASH_IDX(h, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 581 err = zap_idx_to_blk(zap, idx, &blk); 582 if (err != 0) 583 return (err); 584 err = zap_get_leaf_byblk(zap, blk, tx, lt, lp); 585 586 ASSERT(err || ZAP_HASH_IDX(h, (*lp)->l_phys->l_hdr.lh_prefix_len) == 587 (*lp)->l_phys->l_hdr.lh_prefix); 588 return (err); 589 } 590 591 static int 592 zap_expand_leaf(zap_name_t *zn, zap_leaf_t *l, dmu_tx_t *tx, zap_leaf_t **lp) 593 { 594 zap_t *zap = zn->zn_zap; 595 uint64_t hash = zn->zn_hash; 596 zap_leaf_t *nl; 597 int prefix_diff, i, err; 598 uint64_t sibling; 599 int old_prefix_len = l->l_phys->l_hdr.lh_prefix_len; 600 601 ASSERT3U(old_prefix_len, <=, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 602 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 603 604 ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==, 605 l->l_phys->l_hdr.lh_prefix); 606 607 if (zap_tryupgradedir(zap, tx) == 0 || 608 old_prefix_len == zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) { 609 /* We failed to upgrade, or need to grow the pointer table */ 610 objset_t *os = zap->zap_objset; 611 uint64_t object = zap->zap_object; 612 613 zap_put_leaf(l); 614 zap_unlockdir(zap); 615 err = zap_lockdir(os, object, tx, RW_WRITER, 616 FALSE, FALSE, &zn->zn_zap); 617 zap = zn->zn_zap; 618 if (err) 619 return (err); 620 ASSERT(!zap->zap_ismicro); 621 622 while (old_prefix_len == 623 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) { 624 err = zap_grow_ptrtbl(zap, tx); 625 if (err) 626 return (err); 627 } 628 629 err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l); 630 if (err) 631 return (err); 632 633 if (l->l_phys->l_hdr.lh_prefix_len != old_prefix_len) { 634 /* it split while our locks were down */ 635 *lp = l; 636 return (0); 637 } 638 } 639 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); 640 ASSERT3U(old_prefix_len, <, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 641 ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==, 642 l->l_phys->l_hdr.lh_prefix); 643 644 prefix_diff = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift - 645 (old_prefix_len + 1); 646 sibling = (ZAP_HASH_IDX(hash, old_prefix_len + 1) | 1) << prefix_diff; 647 648 /* check for i/o errors before doing zap_leaf_split */ 649 for (i = 0; i < (1ULL<<prefix_diff); i++) { 650 uint64_t blk; 651 err = zap_idx_to_blk(zap, sibling+i, &blk); 652 if (err) 653 return (err); 654 ASSERT3U(blk, ==, l->l_blkid); 655 } 656 657 nl = zap_create_leaf(zap, tx); 658 zap_leaf_split(l, nl, zap->zap_normflags != 0); 659 660 /* set sibling pointers */ 661 for (i = 0; i < (1ULL << prefix_diff); i++) { 662 err = zap_set_idx_to_blk(zap, sibling+i, nl->l_blkid, tx); 663 ASSERT0(err); /* we checked for i/o errors above */ 664 } 665 666 if (hash & (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len))) { 667 /* we want the sibling */ 668 zap_put_leaf(l); 669 *lp = nl; 670 } else { 671 zap_put_leaf(nl); 672 *lp = l; 673 } 674 675 return (0); 676 } 677 678 static void 679 zap_put_leaf_maybe_grow_ptrtbl(zap_name_t *zn, zap_leaf_t *l, dmu_tx_t *tx) 680 { 681 zap_t *zap = zn->zn_zap; 682 int shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift; 683 int leaffull = (l->l_phys->l_hdr.lh_prefix_len == shift && 684 l->l_phys->l_hdr.lh_nfree < ZAP_LEAF_LOW_WATER); 685 686 zap_put_leaf(l); 687 688 if (leaffull || zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk) { 689 int err; 690 691 /* 692 * We are in the middle of growing the pointer table, or 693 * this leaf will soon make us grow it. 694 */ 695 if (zap_tryupgradedir(zap, tx) == 0) { 696 objset_t *os = zap->zap_objset; 697 uint64_t zapobj = zap->zap_object; 698 699 zap_unlockdir(zap); 700 err = zap_lockdir(os, zapobj, tx, 701 RW_WRITER, FALSE, FALSE, &zn->zn_zap); 702 zap = zn->zn_zap; 703 if (err) 704 return; 705 } 706 707 /* could have finished growing while our locks were down */ 708 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift == shift) 709 (void) zap_grow_ptrtbl(zap, tx); 710 } 711 } 712 713 static int 714 fzap_checkname(zap_name_t *zn) 715 { 716 if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN) 717 return (SET_ERROR(ENAMETOOLONG)); 718 return (0); 719 } 720 721 static int 722 fzap_checksize(uint64_t integer_size, uint64_t num_integers) 723 { 724 /* Only integer sizes supported by C */ 725 switch (integer_size) { 726 case 1: 727 case 2: 728 case 4: 729 case 8: 730 break; 731 default: 732 return (SET_ERROR(EINVAL)); 733 } 734 735 if (integer_size * num_integers > ZAP_MAXVALUELEN) 736 return (E2BIG); 737 738 return (0); 739 } 740 741 static int 742 fzap_check(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers) 743 { 744 int err; 745 746 if ((err = fzap_checkname(zn)) != 0) 747 return (err); 748 return (fzap_checksize(integer_size, num_integers)); 749 } 750 751 /* 752 * Routines for manipulating attributes. 753 */ 754 int 755 fzap_lookup(zap_name_t *zn, 756 uint64_t integer_size, uint64_t num_integers, void *buf, 757 char *realname, int rn_len, boolean_t *ncp) 758 { 759 zap_leaf_t *l; 760 int err; 761 zap_entry_handle_t zeh; 762 763 if ((err = fzap_checkname(zn)) != 0) 764 return (err); 765 766 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l); 767 if (err != 0) 768 return (err); 769 err = zap_leaf_lookup(l, zn, &zeh); 770 if (err == 0) { 771 if ((err = fzap_checksize(integer_size, num_integers)) != 0) { 772 zap_put_leaf(l); 773 return (err); 774 } 775 776 err = zap_entry_read(&zeh, integer_size, num_integers, buf); 777 (void) zap_entry_read_name(zn->zn_zap, &zeh, rn_len, realname); 778 if (ncp) { 779 *ncp = zap_entry_normalization_conflict(&zeh, 780 zn, NULL, zn->zn_zap); 781 } 782 } 783 784 zap_put_leaf(l); 785 return (err); 786 } 787 788 int 789 fzap_add_cd(zap_name_t *zn, 790 uint64_t integer_size, uint64_t num_integers, 791 const void *val, uint32_t cd, dmu_tx_t *tx) 792 { 793 zap_leaf_t *l; 794 int err; 795 zap_entry_handle_t zeh; 796 zap_t *zap = zn->zn_zap; 797 798 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 799 ASSERT(!zap->zap_ismicro); 800 ASSERT(fzap_check(zn, integer_size, num_integers) == 0); 801 802 err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l); 803 if (err != 0) 804 return (err); 805 retry: 806 err = zap_leaf_lookup(l, zn, &zeh); 807 if (err == 0) { 808 err = SET_ERROR(EEXIST); 809 goto out; 810 } 811 if (err != ENOENT) 812 goto out; 813 814 err = zap_entry_create(l, zn, cd, 815 integer_size, num_integers, val, &zeh); 816 817 if (err == 0) { 818 zap_increment_num_entries(zap, 1, tx); 819 } else if (err == EAGAIN) { 820 err = zap_expand_leaf(zn, l, tx, &l); 821 zap = zn->zn_zap; /* zap_expand_leaf() may change zap */ 822 if (err == 0) 823 goto retry; 824 } 825 826 out: 827 if (zap != NULL) 828 zap_put_leaf_maybe_grow_ptrtbl(zn, l, tx); 829 return (err); 830 } 831 832 int 833 fzap_add(zap_name_t *zn, 834 uint64_t integer_size, uint64_t num_integers, 835 const void *val, dmu_tx_t *tx) 836 { 837 int err = fzap_check(zn, integer_size, num_integers); 838 if (err != 0) 839 return (err); 840 841 return (fzap_add_cd(zn, integer_size, num_integers, 842 val, ZAP_NEED_CD, tx)); 843 } 844 845 int 846 fzap_update(zap_name_t *zn, 847 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx) 848 { 849 zap_leaf_t *l; 850 int err, create; 851 zap_entry_handle_t zeh; 852 zap_t *zap = zn->zn_zap; 853 854 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); 855 err = fzap_check(zn, integer_size, num_integers); 856 if (err != 0) 857 return (err); 858 859 err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l); 860 if (err != 0) 861 return (err); 862 retry: 863 err = zap_leaf_lookup(l, zn, &zeh); 864 create = (err == ENOENT); 865 ASSERT(err == 0 || err == ENOENT); 866 867 if (create) { 868 err = zap_entry_create(l, zn, ZAP_NEED_CD, 869 integer_size, num_integers, val, &zeh); 870 if (err == 0) 871 zap_increment_num_entries(zap, 1, tx); 872 } else { 873 err = zap_entry_update(&zeh, integer_size, num_integers, val); 874 } 875 876 if (err == EAGAIN) { 877 err = zap_expand_leaf(zn, l, tx, &l); 878 zap = zn->zn_zap; /* zap_expand_leaf() may change zap */ 879 if (err == 0) 880 goto retry; 881 } 882 883 if (zap != NULL) 884 zap_put_leaf_maybe_grow_ptrtbl(zn, l, tx); 885 return (err); 886 } 887 888 int 889 fzap_length(zap_name_t *zn, 890 uint64_t *integer_size, uint64_t *num_integers) 891 { 892 zap_leaf_t *l; 893 int err; 894 zap_entry_handle_t zeh; 895 896 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l); 897 if (err != 0) 898 return (err); 899 err = zap_leaf_lookup(l, zn, &zeh); 900 if (err != 0) 901 goto out; 902 903 if (integer_size) 904 *integer_size = zeh.zeh_integer_size; 905 if (num_integers) 906 *num_integers = zeh.zeh_num_integers; 907 out: 908 zap_put_leaf(l); 909 return (err); 910 } 911 912 int 913 fzap_remove(zap_name_t *zn, dmu_tx_t *tx) 914 { 915 zap_leaf_t *l; 916 int err; 917 zap_entry_handle_t zeh; 918 919 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, tx, RW_WRITER, &l); 920 if (err != 0) 921 return (err); 922 err = zap_leaf_lookup(l, zn, &zeh); 923 if (err == 0) { 924 zap_entry_remove(&zeh); 925 zap_increment_num_entries(zn->zn_zap, -1, tx); 926 } 927 zap_put_leaf(l); 928 return (err); 929 } 930 931 void 932 fzap_prefetch(zap_name_t *zn) 933 { 934 uint64_t idx, blk; 935 zap_t *zap = zn->zn_zap; 936 int bs; 937 938 idx = ZAP_HASH_IDX(zn->zn_hash, 939 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift); 940 if (zap_idx_to_blk(zap, idx, &blk) != 0) 941 return; 942 bs = FZAP_BLOCK_SHIFT(zap); 943 dmu_prefetch(zap->zap_objset, zap->zap_object, blk << bs, 1 << bs); 944 } 945 946 /* 947 * Helper functions for consumers. 948 */ 949 950 uint64_t 951 zap_create_link(objset_t *os, dmu_object_type_t ot, uint64_t parent_obj, 952 const char *name, dmu_tx_t *tx) 953 { 954 uint64_t new_obj; 955 956 VERIFY((new_obj = zap_create(os, ot, DMU_OT_NONE, 0, tx)) > 0); 957 VERIFY(zap_add(os, parent_obj, name, sizeof (uint64_t), 1, &new_obj, 958 tx) == 0); 959 960 return (new_obj); 961 } 962 963 int 964 zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, uint64_t mask, 965 char *name) 966 { 967 zap_cursor_t zc; 968 zap_attribute_t *za; 969 int err; 970 971 if (mask == 0) 972 mask = -1ULL; 973 974 za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP); 975 for (zap_cursor_init(&zc, os, zapobj); 976 (err = zap_cursor_retrieve(&zc, za)) == 0; 977 zap_cursor_advance(&zc)) { 978 if ((za->za_first_integer & mask) == (value & mask)) { 979 (void) strcpy(name, za->za_name); 980 break; 981 } 982 } 983 zap_cursor_fini(&zc); 984 kmem_free(za, sizeof (zap_attribute_t)); 985 return (err); 986 } 987 988 int 989 zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx) 990 { 991 zap_cursor_t zc; 992 zap_attribute_t za; 993 int err; 994 995 for (zap_cursor_init(&zc, os, fromobj); 996 zap_cursor_retrieve(&zc, &za) == 0; 997 (void) zap_cursor_advance(&zc)) { 998 if (za.za_integer_length != 8 || za.za_num_integers != 1) 999 return (SET_ERROR(EINVAL)); 1000 err = zap_add(os, intoobj, za.za_name, 1001 8, 1, &za.za_first_integer, tx); 1002 if (err) 1003 return (err); 1004 } 1005 zap_cursor_fini(&zc); 1006 return (0); 1007 } 1008 1009 int 1010 zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj, 1011 uint64_t value, dmu_tx_t *tx) 1012 { 1013 zap_cursor_t zc; 1014 zap_attribute_t za; 1015 int err; 1016 1017 for (zap_cursor_init(&zc, os, fromobj); 1018 zap_cursor_retrieve(&zc, &za) == 0; 1019 (void) zap_cursor_advance(&zc)) { 1020 if (za.za_integer_length != 8 || za.za_num_integers != 1) 1021 return (SET_ERROR(EINVAL)); 1022 err = zap_add(os, intoobj, za.za_name, 1023 8, 1, &value, tx); 1024 if (err) 1025 return (err); 1026 } 1027 zap_cursor_fini(&zc); 1028 return (0); 1029 } 1030 1031 int 1032 zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj, 1033 dmu_tx_t *tx) 1034 { 1035 zap_cursor_t zc; 1036 zap_attribute_t za; 1037 int err; 1038 1039 for (zap_cursor_init(&zc, os, fromobj); 1040 zap_cursor_retrieve(&zc, &za) == 0; 1041 (void) zap_cursor_advance(&zc)) { 1042 uint64_t delta = 0; 1043 1044 if (za.za_integer_length != 8 || za.za_num_integers != 1) 1045 return (SET_ERROR(EINVAL)); 1046 1047 err = zap_lookup(os, intoobj, za.za_name, 8, 1, &delta); 1048 if (err != 0 && err != ENOENT) 1049 return (err); 1050 delta += za.za_first_integer; 1051 err = zap_update(os, intoobj, za.za_name, 8, 1, &delta, tx); 1052 if (err) 1053 return (err); 1054 } 1055 zap_cursor_fini(&zc); 1056 return (0); 1057 } 1058 1059 int 1060 zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx) 1061 { 1062 char name[20]; 1063 1064 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value); 1065 return (zap_add(os, obj, name, 8, 1, &value, tx)); 1066 } 1067 1068 int 1069 zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx) 1070 { 1071 char name[20]; 1072 1073 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value); 1074 return (zap_remove(os, obj, name, tx)); 1075 } 1076 1077 int 1078 zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value) 1079 { 1080 char name[20]; 1081 1082 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value); 1083 return (zap_lookup(os, obj, name, 8, 1, &value)); 1084 } 1085 1086 int 1087 zap_add_int_key(objset_t *os, uint64_t obj, 1088 uint64_t key, uint64_t value, dmu_tx_t *tx) 1089 { 1090 char name[20]; 1091 1092 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)key); 1093 return (zap_add(os, obj, name, 8, 1, &value, tx)); 1094 } 1095 1096 int 1097 zap_update_int_key(objset_t *os, uint64_t obj, 1098 uint64_t key, uint64_t value, dmu_tx_t *tx) 1099 { 1100 char name[20]; 1101 1102 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)key); 1103 return (zap_update(os, obj, name, 8, 1, &value, tx)); 1104 } 1105 1106 int 1107 zap_lookup_int_key(objset_t *os, uint64_t obj, uint64_t key, uint64_t *valuep) 1108 { 1109 char name[20]; 1110 1111 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)key); 1112 return (zap_lookup(os, obj, name, 8, 1, valuep)); 1113 } 1114 1115 int 1116 zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta, 1117 dmu_tx_t *tx) 1118 { 1119 uint64_t value = 0; 1120 int err; 1121 1122 if (delta == 0) 1123 return (0); 1124 1125 err = zap_lookup(os, obj, name, 8, 1, &value); 1126 if (err != 0 && err != ENOENT) 1127 return (err); 1128 value += delta; 1129 if (value == 0) 1130 err = zap_remove(os, obj, name, tx); 1131 else 1132 err = zap_update(os, obj, name, 8, 1, &value, tx); 1133 return (err); 1134 } 1135 1136 int 1137 zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta, 1138 dmu_tx_t *tx) 1139 { 1140 char name[20]; 1141 1142 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)key); 1143 return (zap_increment(os, obj, name, delta, tx)); 1144 } 1145 1146 /* 1147 * Routines for iterating over the attributes. 1148 */ 1149 1150 int 1151 fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za) 1152 { 1153 int err = ENOENT; 1154 zap_entry_handle_t zeh; 1155 zap_leaf_t *l; 1156 1157 /* retrieve the next entry at or after zc_hash/zc_cd */ 1158 /* if no entry, return ENOENT */ 1159 1160 if (zc->zc_leaf && 1161 (ZAP_HASH_IDX(zc->zc_hash, 1162 zc->zc_leaf->l_phys->l_hdr.lh_prefix_len) != 1163 zc->zc_leaf->l_phys->l_hdr.lh_prefix)) { 1164 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); 1165 zap_put_leaf(zc->zc_leaf); 1166 zc->zc_leaf = NULL; 1167 } 1168 1169 again: 1170 if (zc->zc_leaf == NULL) { 1171 err = zap_deref_leaf(zap, zc->zc_hash, NULL, RW_READER, 1172 &zc->zc_leaf); 1173 if (err != 0) 1174 return (err); 1175 } else { 1176 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); 1177 } 1178 l = zc->zc_leaf; 1179 1180 err = zap_leaf_lookup_closest(l, zc->zc_hash, zc->zc_cd, &zeh); 1181 1182 if (err == ENOENT) { 1183 uint64_t nocare = 1184 (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len)) - 1; 1185 zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1; 1186 zc->zc_cd = 0; 1187 if (l->l_phys->l_hdr.lh_prefix_len == 0 || zc->zc_hash == 0) { 1188 zc->zc_hash = -1ULL; 1189 } else { 1190 zap_put_leaf(zc->zc_leaf); 1191 zc->zc_leaf = NULL; 1192 goto again; 1193 } 1194 } 1195 1196 if (err == 0) { 1197 zc->zc_hash = zeh.zeh_hash; 1198 zc->zc_cd = zeh.zeh_cd; 1199 za->za_integer_length = zeh.zeh_integer_size; 1200 za->za_num_integers = zeh.zeh_num_integers; 1201 if (zeh.zeh_num_integers == 0) { 1202 za->za_first_integer = 0; 1203 } else { 1204 err = zap_entry_read(&zeh, 8, 1, &za->za_first_integer); 1205 ASSERT(err == 0 || err == EOVERFLOW); 1206 } 1207 err = zap_entry_read_name(zap, &zeh, 1208 sizeof (za->za_name), za->za_name); 1209 ASSERT(err == 0); 1210 1211 za->za_normalization_conflict = 1212 zap_entry_normalization_conflict(&zeh, 1213 NULL, za->za_name, zap); 1214 } 1215 rw_exit(&zc->zc_leaf->l_rwlock); 1216 return (err); 1217 } 1218 1219 static void 1220 zap_stats_ptrtbl(zap_t *zap, uint64_t *tbl, int len, zap_stats_t *zs) 1221 { 1222 int i, err; 1223 uint64_t lastblk = 0; 1224 1225 /* 1226 * NB: if a leaf has more pointers than an entire ptrtbl block 1227 * can hold, then it'll be accounted for more than once, since 1228 * we won't have lastblk. 1229 */ 1230 for (i = 0; i < len; i++) { 1231 zap_leaf_t *l; 1232 1233 if (tbl[i] == lastblk) 1234 continue; 1235 lastblk = tbl[i]; 1236 1237 err = zap_get_leaf_byblk(zap, tbl[i], NULL, RW_READER, &l); 1238 if (err == 0) { 1239 zap_leaf_stats(zap, l, zs); 1240 zap_put_leaf(l); 1241 } 1242 } 1243 } 1244 1245 void 1246 fzap_get_stats(zap_t *zap, zap_stats_t *zs) 1247 { 1248 int bs = FZAP_BLOCK_SHIFT(zap); 1249 zs->zs_blocksize = 1ULL << bs; 1250 1251 /* 1252 * Set zap_phys_t fields 1253 */ 1254 zs->zs_num_leafs = zap->zap_f.zap_phys->zap_num_leafs; 1255 zs->zs_num_entries = zap->zap_f.zap_phys->zap_num_entries; 1256 zs->zs_num_blocks = zap->zap_f.zap_phys->zap_freeblk; 1257 zs->zs_block_type = zap->zap_f.zap_phys->zap_block_type; 1258 zs->zs_magic = zap->zap_f.zap_phys->zap_magic; 1259 zs->zs_salt = zap->zap_f.zap_phys->zap_salt; 1260 1261 /* 1262 * Set zap_ptrtbl fields 1263 */ 1264 zs->zs_ptrtbl_len = 1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift; 1265 zs->zs_ptrtbl_nextblk = zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk; 1266 zs->zs_ptrtbl_blks_copied = 1267 zap->zap_f.zap_phys->zap_ptrtbl.zt_blks_copied; 1268 zs->zs_ptrtbl_zt_blk = zap->zap_f.zap_phys->zap_ptrtbl.zt_blk; 1269 zs->zs_ptrtbl_zt_numblks = zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks; 1270 zs->zs_ptrtbl_zt_shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift; 1271 1272 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) { 1273 /* the ptrtbl is entirely in the header block. */ 1274 zap_stats_ptrtbl(zap, &ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), 1275 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap), zs); 1276 } else { 1277 int b; 1278 1279 dmu_prefetch(zap->zap_objset, zap->zap_object, 1280 zap->zap_f.zap_phys->zap_ptrtbl.zt_blk << bs, 1281 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks << bs); 1282 1283 for (b = 0; b < zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks; 1284 b++) { 1285 dmu_buf_t *db; 1286 int err; 1287 1288 err = dmu_buf_hold(zap->zap_objset, zap->zap_object, 1289 (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk + b) << bs, 1290 FTAG, &db, DMU_READ_NO_PREFETCH); 1291 if (err == 0) { 1292 zap_stats_ptrtbl(zap, db->db_data, 1293 1<<(bs-3), zs); 1294 dmu_buf_rele(db, FTAG); 1295 } 1296 } 1297 } 1298 } 1299 1300 int 1301 fzap_count_write(zap_name_t *zn, int add, uint64_t *towrite, 1302 uint64_t *tooverwrite) 1303 { 1304 zap_t *zap = zn->zn_zap; 1305 zap_leaf_t *l; 1306 int err; 1307 1308 /* 1309 * Account for the header block of the fatzap. 1310 */ 1311 if (!add && dmu_buf_freeable(zap->zap_dbuf)) { 1312 *tooverwrite += zap->zap_dbuf->db_size; 1313 } else { 1314 *towrite += zap->zap_dbuf->db_size; 1315 } 1316 1317 /* 1318 * Account for the pointer table blocks. 1319 * If we are adding we need to account for the following cases : 1320 * - If the pointer table is embedded, this operation could force an 1321 * external pointer table. 1322 * - If this already has an external pointer table this operation 1323 * could extend the table. 1324 */ 1325 if (add) { 1326 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0) 1327 *towrite += zap->zap_dbuf->db_size; 1328 else 1329 *towrite += (zap->zap_dbuf->db_size * 3); 1330 } 1331 1332 /* 1333 * Now, check if the block containing leaf is freeable 1334 * and account accordingly. 1335 */ 1336 err = zap_deref_leaf(zap, zn->zn_hash, NULL, RW_READER, &l); 1337 if (err != 0) { 1338 return (err); 1339 } 1340 1341 if (!add && dmu_buf_freeable(l->l_dbuf)) { 1342 *tooverwrite += l->l_dbuf->db_size; 1343 } else { 1344 /* 1345 * If this an add operation, the leaf block could split. 1346 * Hence, we need to account for an additional leaf block. 1347 */ 1348 *towrite += (add ? 2 : 1) * l->l_dbuf->db_size; 1349 } 1350 1351 zap_put_leaf(l); 1352 return (0); 1353 } 1354