1168404Spjd/* 2168404Spjd * CDDL HEADER START 3168404Spjd * 4168404Spjd * The contents of this file are subject to the terms of the 5168404Spjd * Common Development and Distribution License (the "License"). 6168404Spjd * You may not use this file except in compliance with the License. 7168404Spjd * 8168404Spjd * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9168404Spjd * or http://www.opensolaris.org/os/licensing. 10168404Spjd * See the License for the specific language governing permissions 11168404Spjd * and limitations under the License. 12168404Spjd * 13168404Spjd * When distributing Covered Code, include this CDDL HEADER in each 14168404Spjd * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15168404Spjd * If applicable, add the following below this CDDL HEADER, with the 16168404Spjd * fields enclosed by brackets "[]" replaced with your own identifying 17168404Spjd * information: Portions Copyright [yyyy] [name of copyright owner] 18168404Spjd * 19168404Spjd * CDDL HEADER END 20168404Spjd */ 21168404Spjd/* 22219089Spjd * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23243674Smm * Copyright (c) 2012 by Delphix. All rights reserved. 24168404Spjd */ 25168404Spjd 26168404Spjd#ifndef _SYS_ZAP_H 27168404Spjd#define _SYS_ZAP_H 28168404Spjd 29168404Spjd/* 30168404Spjd * ZAP - ZFS Attribute Processor 31168404Spjd * 32185029Spjd * The ZAP is a module which sits on top of the DMU (Data Management 33168404Spjd * Unit) and implements a higher-level storage primitive using DMU 34168404Spjd * objects. Its primary consumer is the ZPL (ZFS Posix Layer). 35168404Spjd * 36168404Spjd * A "zapobj" is a DMU object which the ZAP uses to stores attributes. 37168404Spjd * Users should use only zap routines to access a zapobj - they should 38168404Spjd * not access the DMU object directly using DMU routines. 39168404Spjd * 40168404Spjd * The attributes stored in a zapobj are name-value pairs. The name is 41168404Spjd * a zero-terminated string of up to ZAP_MAXNAMELEN bytes (including 42168404Spjd * terminating NULL). The value is an array of integers, which may be 43168404Spjd * 1, 2, 4, or 8 bytes long. The total space used by the array (number 44168404Spjd * of integers * integer length) can be up to ZAP_MAXVALUELEN bytes. 45168404Spjd * Note that an 8-byte integer value can be used to store the location 46168404Spjd * (object number) of another dmu object (which may be itself a zapobj). 47168404Spjd * Note that you can use a zero-length attribute to store a single bit 48168404Spjd * of information - the attribute is present or not. 49168404Spjd * 50168404Spjd * The ZAP routines are thread-safe. However, you must observe the 51168404Spjd * DMU's restriction that a transaction may not be operated on 52168404Spjd * concurrently. 53168404Spjd * 54168404Spjd * Any of the routines that return an int may return an I/O error (EIO 55168404Spjd * or ECHECKSUM). 56168404Spjd * 57168404Spjd * 58168404Spjd * Implementation / Performance Notes: 59168404Spjd * 60168404Spjd * The ZAP is intended to operate most efficiently on attributes with 61168404Spjd * short (49 bytes or less) names and single 8-byte values, for which 62168404Spjd * the microzap will be used. The ZAP should be efficient enough so 63168404Spjd * that the user does not need to cache these attributes. 64168404Spjd * 65168404Spjd * The ZAP's locking scheme makes its routines thread-safe. Operations 66168404Spjd * on different zapobjs will be processed concurrently. Operations on 67168404Spjd * the same zapobj which only read data will be processed concurrently. 68168404Spjd * Operations on the same zapobj which modify data will be processed 69168404Spjd * concurrently when there are many attributes in the zapobj (because 70168404Spjd * the ZAP uses per-block locking - more than 128 * (number of cpus) 71168404Spjd * small attributes will suffice). 72168404Spjd */ 73168404Spjd 74168404Spjd/* 75168404Spjd * We're using zero-terminated byte strings (ie. ASCII or UTF-8 C 76168404Spjd * strings) for the names of attributes, rather than a byte string 77168404Spjd * bounded by an explicit length. If some day we want to support names 78168404Spjd * in character sets which have embedded zeros (eg. UTF-16, UTF-32), 79168404Spjd * we'll have to add routines for using length-bounded strings. 80168404Spjd */ 81168404Spjd 82168404Spjd#include <sys/dmu.h> 83168404Spjd 84168404Spjd#ifdef __cplusplus 85168404Spjdextern "C" { 86168404Spjd#endif 87168404Spjd 88168404Spjd/* 89252751Sdelphij * Specifies matching criteria for ZAP lookups. 90185029Spjd */ 91185029Spjdtypedef enum matchtype 92185029Spjd{ 93252751Sdelphij /* Only find an exact match (non-normalized) */ 94185029Spjd MT_EXACT, 95252751Sdelphij /* 96252751Sdelphij * If there is an exact match, find that, otherwise find the 97252751Sdelphij * first normalized match. 98252751Sdelphij */ 99185029Spjd MT_BEST, 100252751Sdelphij /* 101252751Sdelphij * Find the "first" normalized (case and Unicode form) match; 102252751Sdelphij * the designated "first" match will not change as long as the 103252751Sdelphij * set of entries with this normalization doesn't change. 104252751Sdelphij */ 105185029Spjd MT_FIRST 106185029Spjd} matchtype_t; 107185029Spjd 108219089Spjdtypedef enum zap_flags { 109219089Spjd /* Use 64-bit hash value (serialized cursors will always use 64-bits) */ 110219089Spjd ZAP_FLAG_HASH64 = 1 << 0, 111219089Spjd /* Key is binary, not string (zap_add_uint64() can be used) */ 112219089Spjd ZAP_FLAG_UINT64_KEY = 1 << 1, 113219089Spjd /* 114219089Spjd * First word of key (which must be an array of uint64) is 115219089Spjd * already randomly distributed. 116219089Spjd */ 117219089Spjd ZAP_FLAG_PRE_HASHED_KEY = 1 << 2, 118219089Spjd} zap_flags_t; 119219089Spjd 120185029Spjd/* 121168404Spjd * Create a new zapobj with no attributes and return its object number. 122185029Spjd * MT_EXACT will cause the zap object to only support MT_EXACT lookups, 123185029Spjd * otherwise any matchtype can be used for lookups. 124185029Spjd * 125185029Spjd * normflags specifies what normalization will be done. values are: 126185029Spjd * 0: no normalization (legacy on-disk format, supports MT_EXACT matching 127185029Spjd * only) 128185029Spjd * U8_TEXTPREP_TOLOWER: case normalization will be performed. 129185029Spjd * MT_FIRST/MT_BEST matching will find entries that match without 130185029Spjd * regard to case (eg. looking for "foo" can find an entry "Foo"). 131185029Spjd * Eventually, other flags will permit unicode normalization as well. 132168404Spjd */ 133168404Spjduint64_t zap_create(objset_t *ds, dmu_object_type_t ot, 134168404Spjd dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 135185029Spjduint64_t zap_create_norm(objset_t *ds, int normflags, dmu_object_type_t ot, 136185029Spjd dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 137219089Spjduint64_t zap_create_flags(objset_t *os, int normflags, zap_flags_t flags, 138219089Spjd dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift, 139219089Spjd dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 140243674Smmuint64_t zap_create_link(objset_t *os, dmu_object_type_t ot, 141243674Smm uint64_t parent_obj, const char *name, dmu_tx_t *tx); 142168404Spjd 143168404Spjd/* 144263391Sdelphij * Initialize an already-allocated object. 145263391Sdelphij */ 146263391Sdelphijvoid mzap_create_impl(objset_t *os, uint64_t obj, int normflags, 147263391Sdelphij zap_flags_t flags, dmu_tx_t *tx); 148263391Sdelphij 149263391Sdelphij/* 150168404Spjd * Create a new zapobj with no attributes from the given (unallocated) 151168404Spjd * object number. 152168404Spjd */ 153168404Spjdint zap_create_claim(objset_t *ds, uint64_t obj, dmu_object_type_t ot, 154168404Spjd dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 155185029Spjdint zap_create_claim_norm(objset_t *ds, uint64_t obj, 156185029Spjd int normflags, dmu_object_type_t ot, 157185029Spjd dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); 158168404Spjd 159168404Spjd/* 160168404Spjd * The zapobj passed in must be a valid ZAP object for all of the 161168404Spjd * following routines. 162168404Spjd */ 163168404Spjd 164168404Spjd/* 165168404Spjd * Destroy this zapobj and all its attributes. 166168404Spjd * 167168404Spjd * Frees the object number using dmu_object_free. 168168404Spjd */ 169168404Spjdint zap_destroy(objset_t *ds, uint64_t zapobj, dmu_tx_t *tx); 170168404Spjd 171168404Spjd/* 172168404Spjd * Manipulate attributes. 173168404Spjd * 174168404Spjd * 'integer_size' is in bytes, and must be 1, 2, 4, or 8. 175168404Spjd */ 176168404Spjd 177168404Spjd/* 178168404Spjd * Retrieve the contents of the attribute with the given name. 179168404Spjd * 180168404Spjd * If the requested attribute does not exist, the call will fail and 181168404Spjd * return ENOENT. 182168404Spjd * 183168404Spjd * If 'integer_size' is smaller than the attribute's integer size, the 184168404Spjd * call will fail and return EINVAL. 185168404Spjd * 186168404Spjd * If 'integer_size' is equal to or larger than the attribute's integer 187252751Sdelphij * size, the call will succeed and return 0. 188168404Spjd * 189252751Sdelphij * When converting to a larger integer size, the integers will be treated as 190252751Sdelphij * unsigned (ie. no sign-extension will be performed). 191252751Sdelphij * 192168404Spjd * 'num_integers' is the length (in integers) of 'buf'. 193168404Spjd * 194168404Spjd * If the attribute is longer than the buffer, as many integers as will 195168404Spjd * fit will be transferred to 'buf'. If the entire attribute was not 196168404Spjd * transferred, the call will return EOVERFLOW. 197252751Sdelphij */ 198252751Sdelphijint zap_lookup(objset_t *ds, uint64_t zapobj, const char *name, 199252751Sdelphij uint64_t integer_size, uint64_t num_integers, void *buf); 200252751Sdelphij 201252751Sdelphij/* 202185029Spjd * If rn_len is nonzero, realname will be set to the name of the found 203185029Spjd * entry (which may be different from the requested name if matchtype is 204185029Spjd * not MT_EXACT). 205185029Spjd * 206185029Spjd * If normalization_conflictp is not NULL, it will be set if there is 207185029Spjd * another name with the same case/unicode normalized form. 208168404Spjd */ 209185029Spjdint zap_lookup_norm(objset_t *ds, uint64_t zapobj, const char *name, 210185029Spjd uint64_t integer_size, uint64_t num_integers, void *buf, 211185029Spjd matchtype_t mt, char *realname, int rn_len, 212185029Spjd boolean_t *normalization_conflictp); 213219089Spjdint zap_lookup_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, 214219089Spjd int key_numints, uint64_t integer_size, uint64_t num_integers, void *buf); 215219089Spjdint zap_contains(objset_t *ds, uint64_t zapobj, const char *name); 216219089Spjdint zap_prefetch_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, 217219089Spjd int key_numints); 218168404Spjd 219209962Smmint zap_count_write(objset_t *os, uint64_t zapobj, const char *name, 220209962Smm int add, uint64_t *towrite, uint64_t *tooverwrite); 221209962Smm 222168404Spjd/* 223168404Spjd * Create an attribute with the given name and value. 224168404Spjd * 225168404Spjd * If an attribute with the given name already exists, the call will 226168404Spjd * fail and return EEXIST. 227168404Spjd */ 228219089Spjdint zap_add(objset_t *ds, uint64_t zapobj, const char *key, 229168404Spjd int integer_size, uint64_t num_integers, 230168404Spjd const void *val, dmu_tx_t *tx); 231219089Spjdint zap_add_uint64(objset_t *ds, uint64_t zapobj, const uint64_t *key, 232219089Spjd int key_numints, int integer_size, uint64_t num_integers, 233219089Spjd const void *val, dmu_tx_t *tx); 234168404Spjd 235168404Spjd/* 236168404Spjd * Set the attribute with the given name to the given value. If an 237168404Spjd * attribute with the given name does not exist, it will be created. If 238168404Spjd * an attribute with the given name already exists, the previous value 239168404Spjd * will be overwritten. The integer_size may be different from the 240168404Spjd * existing attribute's integer size, in which case the attribute's 241168404Spjd * integer size will be updated to the new value. 242168404Spjd */ 243168404Spjdint zap_update(objset_t *ds, uint64_t zapobj, const char *name, 244168404Spjd int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx); 245219089Spjdint zap_update_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, 246219089Spjd int key_numints, 247219089Spjd int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx); 248168404Spjd 249168404Spjd/* 250168404Spjd * Get the length (in integers) and the integer size of the specified 251168404Spjd * attribute. 252168404Spjd * 253168404Spjd * If the requested attribute does not exist, the call will fail and 254168404Spjd * return ENOENT. 255168404Spjd */ 256168404Spjdint zap_length(objset_t *ds, uint64_t zapobj, const char *name, 257168404Spjd uint64_t *integer_size, uint64_t *num_integers); 258219089Spjdint zap_length_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, 259219089Spjd int key_numints, uint64_t *integer_size, uint64_t *num_integers); 260168404Spjd 261168404Spjd/* 262168404Spjd * Remove the specified attribute. 263168404Spjd * 264168404Spjd * If the specified attribute does not exist, the call will fail and 265168404Spjd * return ENOENT. 266168404Spjd */ 267168404Spjdint zap_remove(objset_t *ds, uint64_t zapobj, const char *name, dmu_tx_t *tx); 268185029Spjdint zap_remove_norm(objset_t *ds, uint64_t zapobj, const char *name, 269185029Spjd matchtype_t mt, dmu_tx_t *tx); 270219089Spjdint zap_remove_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, 271219089Spjd int key_numints, dmu_tx_t *tx); 272168404Spjd 273168404Spjd/* 274168404Spjd * Returns (in *count) the number of attributes in the specified zap 275168404Spjd * object. 276168404Spjd */ 277168404Spjdint zap_count(objset_t *ds, uint64_t zapobj, uint64_t *count); 278168404Spjd 279168404Spjd/* 280185029Spjd * Returns (in name) the name of the entry whose (value & mask) 281168404Spjd * (za_first_integer) is value, or ENOENT if not found. The string 282185029Spjd * pointed to by name must be at least 256 bytes long. If mask==0, the 283185029Spjd * match must be exact (ie, same as mask=-1ULL). 284168404Spjd */ 285185029Spjdint zap_value_search(objset_t *os, uint64_t zapobj, 286185029Spjd uint64_t value, uint64_t mask, char *name); 287168404Spjd 288185029Spjd/* 289185029Spjd * Transfer all the entries from fromobj into intoobj. Only works on 290185029Spjd * int_size=8 num_integers=1 values. Fails if there are any duplicated 291185029Spjd * entries. 292185029Spjd */ 293185029Spjdint zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx); 294185029Spjd 295219089Spjd/* Same as zap_join, but set the values to 'value'. */ 296219089Spjdint zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj, 297219089Spjd uint64_t value, dmu_tx_t *tx); 298219089Spjd 299219089Spjd/* Same as zap_join, but add together any duplicated entries. */ 300219089Spjdint zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj, 301219089Spjd dmu_tx_t *tx); 302219089Spjd 303185029Spjd/* 304185029Spjd * Manipulate entries where the name + value are the "same" (the name is 305185029Spjd * a stringified version of the value). 306185029Spjd */ 307185029Spjdint zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx); 308185029Spjdint zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx); 309185029Spjdint zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value); 310219089Spjdint zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta, 311219089Spjd dmu_tx_t *tx); 312185029Spjd 313219089Spjd/* Here the key is an int and the value is a different int. */ 314219089Spjdint zap_add_int_key(objset_t *os, uint64_t obj, 315219089Spjd uint64_t key, uint64_t value, dmu_tx_t *tx); 316243674Smmint zap_update_int_key(objset_t *os, uint64_t obj, 317243674Smm uint64_t key, uint64_t value, dmu_tx_t *tx); 318219089Spjdint zap_lookup_int_key(objset_t *os, uint64_t obj, 319219089Spjd uint64_t key, uint64_t *valuep); 320219089Spjd 321219089Spjdint zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta, 322219089Spjd dmu_tx_t *tx); 323219089Spjd 324168404Spjdstruct zap; 325168404Spjdstruct zap_leaf; 326168404Spjdtypedef struct zap_cursor { 327168404Spjd /* This structure is opaque! */ 328168404Spjd objset_t *zc_objset; 329168404Spjd struct zap *zc_zap; 330168404Spjd struct zap_leaf *zc_leaf; 331168404Spjd uint64_t zc_zapobj; 332219089Spjd uint64_t zc_serialized; 333168404Spjd uint64_t zc_hash; 334168404Spjd uint32_t zc_cd; 335168404Spjd} zap_cursor_t; 336168404Spjd 337168404Spjdtypedef struct { 338168404Spjd int za_integer_length; 339185029Spjd /* 340185029Spjd * za_normalization_conflict will be set if there are additional 341185029Spjd * entries with this normalized form (eg, "foo" and "Foo"). 342185029Spjd */ 343185029Spjd boolean_t za_normalization_conflict; 344168404Spjd uint64_t za_num_integers; 345168404Spjd uint64_t za_first_integer; /* no sign extension for <8byte ints */ 346168404Spjd char za_name[MAXNAMELEN]; 347168404Spjd} zap_attribute_t; 348168404Spjd 349168404Spjd/* 350168404Spjd * The interface for listing all the attributes of a zapobj can be 351168404Spjd * thought of as cursor moving down a list of the attributes one by 352168404Spjd * one. The cookie returned by the zap_cursor_serialize routine is 353168404Spjd * persistent across system calls (and across reboot, even). 354168404Spjd */ 355168404Spjd 356168404Spjd/* 357168404Spjd * Initialize a zap cursor, pointing to the "first" attribute of the 358168404Spjd * zapobj. You must _fini the cursor when you are done with it. 359168404Spjd */ 360168404Spjdvoid zap_cursor_init(zap_cursor_t *zc, objset_t *ds, uint64_t zapobj); 361168404Spjdvoid zap_cursor_fini(zap_cursor_t *zc); 362168404Spjd 363168404Spjd/* 364168404Spjd * Get the attribute currently pointed to by the cursor. Returns 365168404Spjd * ENOENT if at the end of the attributes. 366168404Spjd */ 367168404Spjdint zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za); 368168404Spjd 369168404Spjd/* 370168404Spjd * Advance the cursor to the next attribute. 371168404Spjd */ 372168404Spjdvoid zap_cursor_advance(zap_cursor_t *zc); 373168404Spjd 374168404Spjd/* 375168404Spjd * Get a persistent cookie pointing to the current position of the zap 376168404Spjd * cursor. The low 4 bits in the cookie are always zero, and thus can 377168404Spjd * be used as to differentiate a serialized cookie from a different type 378168404Spjd * of value. The cookie will be less than 2^32 as long as there are 379168404Spjd * fewer than 2^22 (4.2 million) entries in the zap object. 380168404Spjd */ 381168404Spjduint64_t zap_cursor_serialize(zap_cursor_t *zc); 382168404Spjd 383168404Spjd/* 384219089Spjd * Advance the cursor to the attribute having the given key. 385219089Spjd */ 386219089Spjdint zap_cursor_move_to_key(zap_cursor_t *zc, const char *name, matchtype_t mt); 387219089Spjd 388219089Spjd/* 389168404Spjd * Initialize a zap cursor pointing to the position recorded by 390168404Spjd * zap_cursor_serialize (in the "serialized" argument). You can also 391168404Spjd * use a "serialized" argument of 0 to start at the beginning of the 392168404Spjd * zapobj (ie. zap_cursor_init_serialized(..., 0) is equivalent to 393168404Spjd * zap_cursor_init(...).) 394168404Spjd */ 395168404Spjdvoid zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *ds, 396168404Spjd uint64_t zapobj, uint64_t serialized); 397168404Spjd 398168404Spjd 399168404Spjd#define ZAP_HISTOGRAM_SIZE 10 400168404Spjd 401168404Spjdtypedef struct zap_stats { 402168404Spjd /* 403168404Spjd * Size of the pointer table (in number of entries). 404168404Spjd * This is always a power of 2, or zero if it's a microzap. 405168404Spjd * In general, it should be considerably greater than zs_num_leafs. 406168404Spjd */ 407168404Spjd uint64_t zs_ptrtbl_len; 408168404Spjd 409168404Spjd uint64_t zs_blocksize; /* size of zap blocks */ 410168404Spjd 411168404Spjd /* 412168404Spjd * The number of blocks used. Note that some blocks may be 413168404Spjd * wasted because old ptrtbl's and large name/value blocks are 414168404Spjd * not reused. (Although their space is reclaimed, we don't 415168404Spjd * reuse those offsets in the object.) 416168404Spjd */ 417168404Spjd uint64_t zs_num_blocks; 418168404Spjd 419168404Spjd /* 420168404Spjd * Pointer table values from zap_ptrtbl in the zap_phys_t 421168404Spjd */ 422168404Spjd uint64_t zs_ptrtbl_nextblk; /* next (larger) copy start block */ 423168404Spjd uint64_t zs_ptrtbl_blks_copied; /* number source blocks copied */ 424168404Spjd uint64_t zs_ptrtbl_zt_blk; /* starting block number */ 425168404Spjd uint64_t zs_ptrtbl_zt_numblks; /* number of blocks */ 426168404Spjd uint64_t zs_ptrtbl_zt_shift; /* bits to index it */ 427168404Spjd 428168404Spjd /* 429168404Spjd * Values of the other members of the zap_phys_t 430168404Spjd */ 431168404Spjd uint64_t zs_block_type; /* ZBT_HEADER */ 432168404Spjd uint64_t zs_magic; /* ZAP_MAGIC */ 433168404Spjd uint64_t zs_num_leafs; /* The number of leaf blocks */ 434168404Spjd uint64_t zs_num_entries; /* The number of zap entries */ 435168404Spjd uint64_t zs_salt; /* salt to stir into hash function */ 436168404Spjd 437168404Spjd /* 438168404Spjd * Histograms. For all histograms, the last index 439168404Spjd * (ZAP_HISTOGRAM_SIZE-1) includes any values which are greater 440168404Spjd * than what can be represented. For example 441168404Spjd * zs_leafs_with_n5_entries[ZAP_HISTOGRAM_SIZE-1] is the number 442168404Spjd * of leafs with more than 45 entries. 443168404Spjd */ 444168404Spjd 445168404Spjd /* 446168404Spjd * zs_leafs_with_n_pointers[n] is the number of leafs with 447168404Spjd * 2^n pointers to it. 448168404Spjd */ 449168404Spjd uint64_t zs_leafs_with_2n_pointers[ZAP_HISTOGRAM_SIZE]; 450168404Spjd 451168404Spjd /* 452168404Spjd * zs_leafs_with_n_entries[n] is the number of leafs with 453168404Spjd * [n*5, (n+1)*5) entries. In the current implementation, there 454168404Spjd * can be at most 55 entries in any block, but there may be 455168404Spjd * fewer if the name or value is large, or the block is not 456168404Spjd * completely full. 457168404Spjd */ 458168404Spjd uint64_t zs_blocks_with_n5_entries[ZAP_HISTOGRAM_SIZE]; 459168404Spjd 460168404Spjd /* 461168404Spjd * zs_leafs_n_tenths_full[n] is the number of leafs whose 462168404Spjd * fullness is in the range [n/10, (n+1)/10). 463168404Spjd */ 464168404Spjd uint64_t zs_blocks_n_tenths_full[ZAP_HISTOGRAM_SIZE]; 465168404Spjd 466168404Spjd /* 467168404Spjd * zs_entries_using_n_chunks[n] is the number of entries which 468168404Spjd * consume n 24-byte chunks. (Note, large names/values only use 469168404Spjd * one chunk, but contribute to zs_num_blocks_large.) 470168404Spjd */ 471168404Spjd uint64_t zs_entries_using_n_chunks[ZAP_HISTOGRAM_SIZE]; 472168404Spjd 473168404Spjd /* 474168404Spjd * zs_buckets_with_n_entries[n] is the number of buckets (each 475168404Spjd * leaf has 64 buckets) with n entries. 476168404Spjd * zs_buckets_with_n_entries[1] should be very close to 477168404Spjd * zs_num_entries. 478168404Spjd */ 479168404Spjd uint64_t zs_buckets_with_n_entries[ZAP_HISTOGRAM_SIZE]; 480168404Spjd} zap_stats_t; 481168404Spjd 482168404Spjd/* 483168404Spjd * Get statistics about a ZAP object. Note: you need to be aware of the 484168404Spjd * internal implementation of the ZAP to correctly interpret some of the 485168404Spjd * statistics. This interface shouldn't be relied on unless you really 486168404Spjd * know what you're doing. 487168404Spjd */ 488168404Spjdint zap_get_stats(objset_t *ds, uint64_t zapobj, zap_stats_t *zs); 489168404Spjd 490168404Spjd#ifdef __cplusplus 491168404Spjd} 492168404Spjd#endif 493168404Spjd 494168404Spjd#endif /* _SYS_ZAP_H */ 495