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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
1d3ba0bf 9 * or https://opensource.org/licenses/CDDL-1.0.
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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 */
9b7b9cd3 21
34dc7c2f 22/*
428870ff 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
d9b4bf06 24 * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
9b7b9cd3 25 * Copyright 2017 Nexenta Systems, Inc.
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26 */
27
28#ifndef _SYS_ZAP_H
29#define _SYS_ZAP_H
30
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31/*
32 * ZAP - ZFS Attribute Processor
33 *
34 * The ZAP is a module which sits on top of the DMU (Data Management
35 * Unit) and implements a higher-level storage primitive using DMU
36 * objects. Its primary consumer is the ZPL (ZFS Posix Layer).
37 *
38 * A "zapobj" is a DMU object which the ZAP uses to stores attributes.
39 * Users should use only zap routines to access a zapobj - they should
40 * not access the DMU object directly using DMU routines.
41 *
42 * The attributes stored in a zapobj are name-value pairs. The name is
43 * a zero-terminated string of up to ZAP_MAXNAMELEN bytes (including
44 * terminating NULL). The value is an array of integers, which may be
45 * 1, 2, 4, or 8 bytes long. The total space used by the array (number
46 * of integers * integer length) can be up to ZAP_MAXVALUELEN bytes.
47 * Note that an 8-byte integer value can be used to store the location
48 * (object number) of another dmu object (which may be itself a zapobj).
49 * Note that you can use a zero-length attribute to store a single bit
50 * of information - the attribute is present or not.
51 *
52 * The ZAP routines are thread-safe. However, you must observe the
53 * DMU's restriction that a transaction may not be operated on
54 * concurrently.
55 *
56 * Any of the routines that return an int may return an I/O error (EIO
57 * or ECHECKSUM).
58 *
59 *
60 * Implementation / Performance Notes:
61 *
62 * The ZAP is intended to operate most efficiently on attributes with
63 * short (49 bytes or less) names and single 8-byte values, for which
64 * the microzap will be used. The ZAP should be efficient enough so
65 * that the user does not need to cache these attributes.
66 *
67 * The ZAP's locking scheme makes its routines thread-safe. Operations
68 * on different zapobjs will be processed concurrently. Operations on
69 * the same zapobj which only read data will be processed concurrently.
70 * Operations on the same zapobj which modify data will be processed
71 * concurrently when there are many attributes in the zapobj (because
72 * the ZAP uses per-block locking - more than 128 * (number of cpus)
73 * small attributes will suffice).
74 */
75
76/*
77 * We're using zero-terminated byte strings (ie. ASCII or UTF-8 C
78 * strings) for the names of attributes, rather than a byte string
79 * bounded by an explicit length. If some day we want to support names
80 * in character sets which have embedded zeros (eg. UTF-16, UTF-32),
81 * we'll have to add routines for using length-bounded strings.
82 */
83
84#include <sys/dmu.h>
85
86#ifdef __cplusplus
87extern "C" {
88#endif
89
34dc7c2f 90/*
d3cc8b15 91 * Specifies matching criteria for ZAP lookups.
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92 * MT_NORMALIZE Use ZAP normalization flags, which can include both
93 * unicode normalization and case-insensitivity.
94 * MT_MATCH_CASE Do case-sensitive lookups even if MT_NORMALIZE is
95 * specified and ZAP normalization flags include
96 * U8_TEXTPREP_TOUPPER.
34dc7c2f 97 */
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98typedef enum matchtype {
99 MT_NORMALIZE = 1 << 0,
100 MT_MATCH_CASE = 1 << 1,
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101} matchtype_t;
102
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103typedef enum zap_flags {
104 /* Use 64-bit hash value (serialized cursors will always use 64-bits) */
105 ZAP_FLAG_HASH64 = 1 << 0,
106 /* Key is binary, not string (zap_add_uint64() can be used) */
107 ZAP_FLAG_UINT64_KEY = 1 << 1,
108 /*
109 * First word of key (which must be an array of uint64) is
110 * already randomly distributed.
111 */
112 ZAP_FLAG_PRE_HASHED_KEY = 1 << 2,
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113#if defined(__linux__) && defined(_KERNEL)
114} zfs_zap_flags_t;
115#define zap_flags_t zfs_zap_flags_t
116#else
428870ff 117} zap_flags_t;
91350681 118#endif
428870ff 119
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120/*
121 * Create a new zapobj with no attributes and return its object number.
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122 */
123uint64_t zap_create(objset_t *ds, dmu_object_type_t ot,
124 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
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125uint64_t zap_create_dnsize(objset_t *ds, dmu_object_type_t ot,
126 dmu_object_type_t bonustype, int bonuslen, int dnodesize, dmu_tx_t *tx);
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127uint64_t zap_create_norm(objset_t *ds, int normflags, dmu_object_type_t ot,
128 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
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129uint64_t zap_create_norm_dnsize(objset_t *ds, int normflags,
130 dmu_object_type_t ot, dmu_object_type_t bonustype, int bonuslen,
131 int dnodesize, dmu_tx_t *tx);
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132uint64_t zap_create_flags(objset_t *os, int normflags, zap_flags_t flags,
133 dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift,
134 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
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135uint64_t zap_create_flags_dnsize(objset_t *os, int normflags,
136 zap_flags_t flags, dmu_object_type_t ot, int leaf_blockshift,
137 int indirect_blockshift, dmu_object_type_t bonustype, int bonuslen,
138 int dnodesize, dmu_tx_t *tx);
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139uint64_t zap_create_hold(objset_t *os, int normflags, zap_flags_t flags,
140 dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift,
141 dmu_object_type_t bonustype, int bonuslen, int dnodesize,
dd66857d 142 dnode_t **allocated_dnode, const void *tag, dmu_tx_t *tx);
6955b401 143
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144uint64_t zap_create_link(objset_t *os, dmu_object_type_t ot,
145 uint64_t parent_obj, const char *name, dmu_tx_t *tx);
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146uint64_t zap_create_link_dnsize(objset_t *os, dmu_object_type_t ot,
147 uint64_t parent_obj, const char *name, int dnodesize, dmu_tx_t *tx);
34dc7c2f 148
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149/*
150 * Initialize an already-allocated object.
151 */
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152void mzap_create_impl(dnode_t *dn, int normflags, zap_flags_t flags,
153 dmu_tx_t *tx);
fa86b5db 154
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155/*
156 * Create a new zapobj with no attributes from the given (unallocated)
157 * object number.
158 */
159int zap_create_claim(objset_t *ds, uint64_t obj, dmu_object_type_t ot,
160 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
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161int zap_create_claim_dnsize(objset_t *ds, uint64_t obj, dmu_object_type_t ot,
162 dmu_object_type_t bonustype, int bonuslen, int dnodesize, dmu_tx_t *tx);
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163int zap_create_claim_norm(objset_t *ds, uint64_t obj,
164 int normflags, dmu_object_type_t ot,
165 dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx);
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166int zap_create_claim_norm_dnsize(objset_t *ds, uint64_t obj,
167 int normflags, dmu_object_type_t ot,
168 dmu_object_type_t bonustype, int bonuslen, int dnodesize, dmu_tx_t *tx);
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169
170/*
171 * The zapobj passed in must be a valid ZAP object for all of the
172 * following routines.
173 */
174
175/*
176 * Destroy this zapobj and all its attributes.
177 *
178 * Frees the object number using dmu_object_free.
179 */
180int zap_destroy(objset_t *ds, uint64_t zapobj, dmu_tx_t *tx);
181
182/*
183 * Manipulate attributes.
184 *
185 * 'integer_size' is in bytes, and must be 1, 2, 4, or 8.
186 */
187
188/*
189 * Retrieve the contents of the attribute with the given name.
190 *
191 * If the requested attribute does not exist, the call will fail and
192 * return ENOENT.
193 *
194 * If 'integer_size' is smaller than the attribute's integer size, the
195 * call will fail and return EINVAL.
196 *
197 * If 'integer_size' is equal to or larger than the attribute's integer
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198 * size, the call will succeed and return 0.
199 *
200 * When converting to a larger integer size, the integers will be treated as
201 * unsigned (ie. no sign-extension will be performed).
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202 *
203 * 'num_integers' is the length (in integers) of 'buf'.
204 *
205 * If the attribute is longer than the buffer, as many integers as will
206 * fit will be transferred to 'buf'. If the entire attribute was not
207 * transferred, the call will return EOVERFLOW.
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208 */
209int zap_lookup(objset_t *ds, uint64_t zapobj, const char *name,
210 uint64_t integer_size, uint64_t num_integers, void *buf);
211
212/*
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213 * If rn_len is nonzero, realname will be set to the name of the found
214 * entry (which may be different from the requested name if matchtype is
215 * not MT_EXACT).
216 *
217 * If normalization_conflictp is not NULL, it will be set if there is
218 * another name with the same case/unicode normalized form.
219 */
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220int zap_lookup_norm(objset_t *ds, uint64_t zapobj, const char *name,
221 uint64_t integer_size, uint64_t num_integers, void *buf,
222 matchtype_t mt, char *realname, int rn_len,
223 boolean_t *normalization_conflictp);
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224int zap_lookup_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
225 int key_numints, uint64_t integer_size, uint64_t num_integers, void *buf);
226int zap_contains(objset_t *ds, uint64_t zapobj, const char *name);
07248450 227int zap_prefetch(objset_t *os, uint64_t zapobj, const char *name);
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228int zap_prefetch_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
229 int key_numints);
34dc7c2f 230
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231int zap_lookup_by_dnode(dnode_t *dn, const char *name,
232 uint64_t integer_size, uint64_t num_integers, void *buf);
233int zap_lookup_norm_by_dnode(dnode_t *dn, const char *name,
234 uint64_t integer_size, uint64_t num_integers, void *buf,
235 matchtype_t mt, char *realname, int rn_len,
236 boolean_t *ncp);
237
238int zap_count_write_by_dnode(dnode_t *dn, const char *name,
c13060e4 239 int add, zfs_refcount_t *towrite, zfs_refcount_t *tooverwrite);
9babb374 240
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241/*
242 * Create an attribute with the given name and value.
243 *
244 * If an attribute with the given name already exists, the call will
245 * fail and return EEXIST.
246 */
428870ff 247int zap_add(objset_t *ds, uint64_t zapobj, const char *key,
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248 int integer_size, uint64_t num_integers,
249 const void *val, dmu_tx_t *tx);
0eef1bde 250int zap_add_by_dnode(dnode_t *dn, const char *key,
251 int integer_size, uint64_t num_integers,
252 const void *val, dmu_tx_t *tx);
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253int zap_add_uint64(objset_t *ds, uint64_t zapobj, const uint64_t *key,
254 int key_numints, int integer_size, uint64_t num_integers,
255 const void *val, dmu_tx_t *tx);
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256int zap_add_uint64_by_dnode(dnode_t *dn, const uint64_t *key,
257 int key_numints, int integer_size, uint64_t num_integers,
258 const void *val, dmu_tx_t *tx);
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259
260/*
261 * Set the attribute with the given name to the given value. If an
262 * attribute with the given name does not exist, it will be created. If
263 * an attribute with the given name already exists, the previous value
264 * will be overwritten. The integer_size may be different from the
265 * existing attribute's integer size, in which case the attribute's
266 * integer size will be updated to the new value.
267 */
268int zap_update(objset_t *ds, uint64_t zapobj, const char *name,
269 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx);
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270int zap_update_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
271 int key_numints,
272 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx);
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273int zap_update_uint64_by_dnode(dnode_t *dn, const uint64_t *key,
274 int key_numints,
275 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx);
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276
277/*
278 * Get the length (in integers) and the integer size of the specified
279 * attribute.
280 *
281 * If the requested attribute does not exist, the call will fail and
282 * return ENOENT.
283 */
284int zap_length(objset_t *ds, uint64_t zapobj, const char *name,
285 uint64_t *integer_size, uint64_t *num_integers);
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286int zap_length_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
287 int key_numints, uint64_t *integer_size, uint64_t *num_integers);
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288
289/*
290 * Remove the specified attribute.
291 *
292 * If the specified attribute does not exist, the call will fail and
293 * return ENOENT.
294 */
295int zap_remove(objset_t *ds, uint64_t zapobj, const char *name, dmu_tx_t *tx);
296int zap_remove_norm(objset_t *ds, uint64_t zapobj, const char *name,
297 matchtype_t mt, dmu_tx_t *tx);
0eef1bde 298int zap_remove_by_dnode(dnode_t *dn, const char *name, dmu_tx_t *tx);
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299int zap_remove_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
300 int key_numints, dmu_tx_t *tx);
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301int zap_remove_uint64_by_dnode(dnode_t *dn, const uint64_t *key,
302 int key_numints, dmu_tx_t *tx);
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303
304/*
305 * Returns (in *count) the number of attributes in the specified zap
306 * object.
307 */
308int zap_count(objset_t *ds, uint64_t zapobj, uint64_t *count);
309
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310/*
311 * Returns (in name) the name of the entry whose (value & mask)
312 * (za_first_integer) is value, or ENOENT if not found. The string
313 * pointed to by name must be at least 256 bytes long. If mask==0, the
314 * match must be exact (ie, same as mask=-1ULL).
315 */
316int zap_value_search(objset_t *os, uint64_t zapobj,
317 uint64_t value, uint64_t mask, char *name);
318
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319/*
320 * Transfer all the entries from fromobj into intoobj. Only works on
321 * int_size=8 num_integers=1 values. Fails if there are any duplicated
322 * entries.
323 */
324int zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx);
325
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326/* Same as zap_join, but set the values to 'value'. */
327int zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj,
328 uint64_t value, dmu_tx_t *tx);
329
330/* Same as zap_join, but add together any duplicated entries. */
331int zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj,
332 dmu_tx_t *tx);
333
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334/*
335 * Manipulate entries where the name + value are the "same" (the name is
336 * a stringified version of the value).
337 */
338int zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx);
339int zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx);
340int zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value);
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341int zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta,
342 dmu_tx_t *tx);
343
344/* Here the key is an int and the value is a different int. */
345int zap_add_int_key(objset_t *os, uint64_t obj,
346 uint64_t key, uint64_t value, dmu_tx_t *tx);
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347int zap_update_int_key(objset_t *os, uint64_t obj,
348 uint64_t key, uint64_t value, dmu_tx_t *tx);
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349int zap_lookup_int_key(objset_t *os, uint64_t obj,
350 uint64_t key, uint64_t *valuep);
351
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352int zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta,
353 dmu_tx_t *tx);
b128c09f 354
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355struct zap;
356struct zap_leaf;
357typedef struct zap_cursor {
358 /* This structure is opaque! */
359 objset_t *zc_objset;
360 struct zap *zc_zap;
361 struct zap_leaf *zc_leaf;
362 uint64_t zc_zapobj;
428870ff 363 uint64_t zc_serialized;
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364 uint64_t zc_hash;
365 uint32_t zc_cd;
d9b4bf06 366 boolean_t zc_prefetch;
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367} zap_cursor_t;
368
369typedef struct {
370 int za_integer_length;
371 /*
372 * za_normalization_conflict will be set if there are additional
373 * entries with this normalized form (eg, "foo" and "Foo").
374 */
375 boolean_t za_normalization_conflict;
376 uint64_t za_num_integers;
377 uint64_t za_first_integer; /* no sign extension for <8byte ints */
eca7b760 378 char za_name[ZAP_MAXNAMELEN];
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379} zap_attribute_t;
380
381/*
382 * The interface for listing all the attributes of a zapobj can be
383 * thought of as cursor moving down a list of the attributes one by
384 * one. The cookie returned by the zap_cursor_serialize routine is
385 * persistent across system calls (and across reboot, even).
386 */
387
388/*
389 * Initialize a zap cursor, pointing to the "first" attribute of the
390 * zapobj. You must _fini the cursor when you are done with it.
391 */
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392void zap_cursor_init(zap_cursor_t *zc, objset_t *os, uint64_t zapobj);
393void zap_cursor_init_noprefetch(zap_cursor_t *zc, objset_t *os,
394 uint64_t zapobj);
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395void zap_cursor_fini(zap_cursor_t *zc);
396
397/*
398 * Get the attribute currently pointed to by the cursor. Returns
399 * ENOENT if at the end of the attributes.
400 */
401int zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za);
402
403/*
404 * Advance the cursor to the next attribute.
405 */
406void zap_cursor_advance(zap_cursor_t *zc);
407
408/*
409 * Get a persistent cookie pointing to the current position of the zap
410 * cursor. The low 4 bits in the cookie are always zero, and thus can
411 * be used as to differentiate a serialized cookie from a different type
412 * of value. The cookie will be less than 2^32 as long as there are
413 * fewer than 2^22 (4.2 million) entries in the zap object.
414 */
415uint64_t zap_cursor_serialize(zap_cursor_t *zc);
416
417/*
418 * Initialize a zap cursor pointing to the position recorded by
419 * zap_cursor_serialize (in the "serialized" argument). You can also
420 * use a "serialized" argument of 0 to start at the beginning of the
421 * zapobj (ie. zap_cursor_init_serialized(..., 0) is equivalent to
422 * zap_cursor_init(...).)
423 */
424void zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *ds,
425 uint64_t zapobj, uint64_t serialized);
426
427
428#define ZAP_HISTOGRAM_SIZE 10
429
430typedef struct zap_stats {
431 /*
432 * Size of the pointer table (in number of entries).
433 * This is always a power of 2, or zero if it's a microzap.
434 * In general, it should be considerably greater than zs_num_leafs.
435 */
436 uint64_t zs_ptrtbl_len;
437
438 uint64_t zs_blocksize; /* size of zap blocks */
439
440 /*
441 * The number of blocks used. Note that some blocks may be
442 * wasted because old ptrtbl's and large name/value blocks are
443 * not reused. (Although their space is reclaimed, we don't
444 * reuse those offsets in the object.)
445 */
446 uint64_t zs_num_blocks;
447
448 /*
449 * Pointer table values from zap_ptrtbl in the zap_phys_t
450 */
451 uint64_t zs_ptrtbl_nextblk; /* next (larger) copy start block */
452 uint64_t zs_ptrtbl_blks_copied; /* number source blocks copied */
453 uint64_t zs_ptrtbl_zt_blk; /* starting block number */
454 uint64_t zs_ptrtbl_zt_numblks; /* number of blocks */
455 uint64_t zs_ptrtbl_zt_shift; /* bits to index it */
456
457 /*
458 * Values of the other members of the zap_phys_t
459 */
460 uint64_t zs_block_type; /* ZBT_HEADER */
461 uint64_t zs_magic; /* ZAP_MAGIC */
462 uint64_t zs_num_leafs; /* The number of leaf blocks */
463 uint64_t zs_num_entries; /* The number of zap entries */
464 uint64_t zs_salt; /* salt to stir into hash function */
465
466 /*
467 * Histograms. For all histograms, the last index
468 * (ZAP_HISTOGRAM_SIZE-1) includes any values which are greater
469 * than what can be represented. For example
470 * zs_leafs_with_n5_entries[ZAP_HISTOGRAM_SIZE-1] is the number
471 * of leafs with more than 45 entries.
472 */
473
474 /*
475 * zs_leafs_with_n_pointers[n] is the number of leafs with
476 * 2^n pointers to it.
477 */
478 uint64_t zs_leafs_with_2n_pointers[ZAP_HISTOGRAM_SIZE];
479
480 /*
481 * zs_leafs_with_n_entries[n] is the number of leafs with
482 * [n*5, (n+1)*5) entries. In the current implementation, there
483 * can be at most 55 entries in any block, but there may be
484 * fewer if the name or value is large, or the block is not
485 * completely full.
486 */
487 uint64_t zs_blocks_with_n5_entries[ZAP_HISTOGRAM_SIZE];
488
489 /*
490 * zs_leafs_n_tenths_full[n] is the number of leafs whose
491 * fullness is in the range [n/10, (n+1)/10).
492 */
493 uint64_t zs_blocks_n_tenths_full[ZAP_HISTOGRAM_SIZE];
494
495 /*
496 * zs_entries_using_n_chunks[n] is the number of entries which
497 * consume n 24-byte chunks. (Note, large names/values only use
498 * one chunk, but contribute to zs_num_blocks_large.)
499 */
500 uint64_t zs_entries_using_n_chunks[ZAP_HISTOGRAM_SIZE];
501
502 /*
503 * zs_buckets_with_n_entries[n] is the number of buckets (each
504 * leaf has 64 buckets) with n entries.
505 * zs_buckets_with_n_entries[1] should be very close to
506 * zs_num_entries.
507 */
508 uint64_t zs_buckets_with_n_entries[ZAP_HISTOGRAM_SIZE];
509} zap_stats_t;
510
511/*
512 * Get statistics about a ZAP object. Note: you need to be aware of the
513 * internal implementation of the ZAP to correctly interpret some of the
514 * statistics. This interface shouldn't be relied on unless you really
515 * know what you're doing.
516 */
517int zap_get_stats(objset_t *ds, uint64_t zapobj, zap_stats_t *zs);
518
519#ifdef __cplusplus
520}
521#endif
522
523#endif /* _SYS_ZAP_H */