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34dc7c2f BB |
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 | /* | |
428870ff | 22 | * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. |
9ae529ec | 23 | * Copyright (c) 2012 by Delphix. All rights reserved. |
34dc7c2f BB |
24 | */ |
25 | ||
26 | #ifndef _SYS_ZAP_H | |
27 | #define _SYS_ZAP_H | |
28 | ||
34dc7c2f BB |
29 | /* |
30 | * ZAP - ZFS Attribute Processor | |
31 | * | |
32 | * The ZAP is a module which sits on top of the DMU (Data Management | |
33 | * Unit) and implements a higher-level storage primitive using DMU | |
34 | * objects. Its primary consumer is the ZPL (ZFS Posix Layer). | |
35 | * | |
36 | * A "zapobj" is a DMU object which the ZAP uses to stores attributes. | |
37 | * Users should use only zap routines to access a zapobj - they should | |
38 | * not access the DMU object directly using DMU routines. | |
39 | * | |
40 | * The attributes stored in a zapobj are name-value pairs. The name is | |
41 | * a zero-terminated string of up to ZAP_MAXNAMELEN bytes (including | |
42 | * terminating NULL). The value is an array of integers, which may be | |
43 | * 1, 2, 4, or 8 bytes long. The total space used by the array (number | |
44 | * of integers * integer length) can be up to ZAP_MAXVALUELEN bytes. | |
45 | * Note that an 8-byte integer value can be used to store the location | |
46 | * (object number) of another dmu object (which may be itself a zapobj). | |
47 | * Note that you can use a zero-length attribute to store a single bit | |
48 | * of information - the attribute is present or not. | |
49 | * | |
50 | * The ZAP routines are thread-safe. However, you must observe the | |
51 | * DMU's restriction that a transaction may not be operated on | |
52 | * concurrently. | |
53 | * | |
54 | * Any of the routines that return an int may return an I/O error (EIO | |
55 | * or ECHECKSUM). | |
56 | * | |
57 | * | |
58 | * Implementation / Performance Notes: | |
59 | * | |
60 | * The ZAP is intended to operate most efficiently on attributes with | |
61 | * short (49 bytes or less) names and single 8-byte values, for which | |
62 | * the microzap will be used. The ZAP should be efficient enough so | |
63 | * that the user does not need to cache these attributes. | |
64 | * | |
65 | * The ZAP's locking scheme makes its routines thread-safe. Operations | |
66 | * on different zapobjs will be processed concurrently. Operations on | |
67 | * the same zapobj which only read data will be processed concurrently. | |
68 | * Operations on the same zapobj which modify data will be processed | |
69 | * concurrently when there are many attributes in the zapobj (because | |
70 | * the ZAP uses per-block locking - more than 128 * (number of cpus) | |
71 | * small attributes will suffice). | |
72 | */ | |
73 | ||
74 | /* | |
75 | * We're using zero-terminated byte strings (ie. ASCII or UTF-8 C | |
76 | * strings) for the names of attributes, rather than a byte string | |
77 | * bounded by an explicit length. If some day we want to support names | |
78 | * in character sets which have embedded zeros (eg. UTF-16, UTF-32), | |
79 | * we'll have to add routines for using length-bounded strings. | |
80 | */ | |
81 | ||
82 | #include <sys/dmu.h> | |
83 | ||
84 | #ifdef __cplusplus | |
85 | extern "C" { | |
86 | #endif | |
87 | ||
34dc7c2f | 88 | /* |
a08ee875 | 89 | * Specifies matching criteria for ZAP lookups. |
34dc7c2f BB |
90 | */ |
91 | typedef enum matchtype | |
92 | { | |
a08ee875 | 93 | /* Only find an exact match (non-normalized) */ |
34dc7c2f | 94 | MT_EXACT, |
a08ee875 LG |
95 | /* |
96 | * If there is an exact match, find that, otherwise find the | |
97 | * first normalized match. | |
98 | */ | |
34dc7c2f | 99 | MT_BEST, |
a08ee875 LG |
100 | /* |
101 | * Find the "first" normalized (case and Unicode form) match; | |
102 | * the designated "first" match will not change as long as the | |
103 | * set of entries with this normalization doesn't change. | |
104 | */ | |
34dc7c2f BB |
105 | MT_FIRST |
106 | } matchtype_t; | |
107 | ||
428870ff BB |
108 | typedef enum zap_flags { |
109 | /* Use 64-bit hash value (serialized cursors will always use 64-bits) */ | |
110 | ZAP_FLAG_HASH64 = 1 << 0, | |
111 | /* Key is binary, not string (zap_add_uint64() can be used) */ | |
112 | ZAP_FLAG_UINT64_KEY = 1 << 1, | |
113 | /* | |
114 | * First word of key (which must be an array of uint64) is | |
115 | * already randomly distributed. | |
116 | */ | |
117 | ZAP_FLAG_PRE_HASHED_KEY = 1 << 2, | |
118 | } zap_flags_t; | |
119 | ||
34dc7c2f BB |
120 | /* |
121 | * Create a new zapobj with no attributes and return its object number. | |
122 | * MT_EXACT will cause the zap object to only support MT_EXACT lookups, | |
123 | * otherwise any matchtype can be used for lookups. | |
124 | * | |
125 | * normflags specifies what normalization will be done. values are: | |
126 | * 0: no normalization (legacy on-disk format, supports MT_EXACT matching | |
127 | * only) | |
128 | * U8_TEXTPREP_TOLOWER: case normalization will be performed. | |
129 | * MT_FIRST/MT_BEST matching will find entries that match without | |
130 | * regard to case (eg. looking for "foo" can find an entry "Foo"). | |
131 | * Eventually, other flags will permit unicode normalization as well. | |
132 | */ | |
133 | uint64_t zap_create(objset_t *ds, dmu_object_type_t ot, | |
134 | dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); | |
135 | uint64_t zap_create_norm(objset_t *ds, int normflags, dmu_object_type_t ot, | |
136 | dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); | |
428870ff BB |
137 | uint64_t zap_create_flags(objset_t *os, int normflags, zap_flags_t flags, |
138 | dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift, | |
139 | dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); | |
9ae529ec CS |
140 | uint64_t zap_create_link(objset_t *os, dmu_object_type_t ot, |
141 | uint64_t parent_obj, const char *name, dmu_tx_t *tx); | |
34dc7c2f BB |
142 | |
143 | /* | |
144 | * Create a new zapobj with no attributes from the given (unallocated) | |
145 | * object number. | |
146 | */ | |
147 | int zap_create_claim(objset_t *ds, uint64_t obj, dmu_object_type_t ot, | |
148 | dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); | |
149 | int zap_create_claim_norm(objset_t *ds, uint64_t obj, | |
150 | int normflags, dmu_object_type_t ot, | |
151 | dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx); | |
152 | ||
153 | /* | |
154 | * The zapobj passed in must be a valid ZAP object for all of the | |
155 | * following routines. | |
156 | */ | |
157 | ||
158 | /* | |
159 | * Destroy this zapobj and all its attributes. | |
160 | * | |
161 | * Frees the object number using dmu_object_free. | |
162 | */ | |
163 | int zap_destroy(objset_t *ds, uint64_t zapobj, dmu_tx_t *tx); | |
164 | ||
165 | /* | |
166 | * Manipulate attributes. | |
167 | * | |
168 | * 'integer_size' is in bytes, and must be 1, 2, 4, or 8. | |
169 | */ | |
170 | ||
171 | /* | |
172 | * Retrieve the contents of the attribute with the given name. | |
173 | * | |
174 | * If the requested attribute does not exist, the call will fail and | |
175 | * return ENOENT. | |
176 | * | |
177 | * If 'integer_size' is smaller than the attribute's integer size, the | |
178 | * call will fail and return EINVAL. | |
179 | * | |
180 | * If 'integer_size' is equal to or larger than the attribute's integer | |
a08ee875 LG |
181 | * size, the call will succeed and return 0. |
182 | * | |
183 | * When converting to a larger integer size, the integers will be treated as | |
184 | * unsigned (ie. no sign-extension will be performed). | |
34dc7c2f BB |
185 | * |
186 | * 'num_integers' is the length (in integers) of 'buf'. | |
187 | * | |
188 | * If the attribute is longer than the buffer, as many integers as will | |
189 | * fit will be transferred to 'buf'. If the entire attribute was not | |
190 | * transferred, the call will return EOVERFLOW. | |
a08ee875 LG |
191 | */ |
192 | int zap_lookup(objset_t *ds, uint64_t zapobj, const char *name, | |
193 | uint64_t integer_size, uint64_t num_integers, void *buf); | |
194 | ||
195 | /* | |
34dc7c2f BB |
196 | * If rn_len is nonzero, realname will be set to the name of the found |
197 | * entry (which may be different from the requested name if matchtype is | |
198 | * not MT_EXACT). | |
199 | * | |
200 | * If normalization_conflictp is not NULL, it will be set if there is | |
201 | * another name with the same case/unicode normalized form. | |
202 | */ | |
34dc7c2f BB |
203 | int zap_lookup_norm(objset_t *ds, uint64_t zapobj, const char *name, |
204 | uint64_t integer_size, uint64_t num_integers, void *buf, | |
205 | matchtype_t mt, char *realname, int rn_len, | |
206 | boolean_t *normalization_conflictp); | |
428870ff BB |
207 | int zap_lookup_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, |
208 | int key_numints, uint64_t integer_size, uint64_t num_integers, void *buf); | |
209 | int zap_contains(objset_t *ds, uint64_t zapobj, const char *name); | |
210 | int zap_prefetch_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, | |
211 | int key_numints); | |
34dc7c2f | 212 | |
9babb374 | 213 | int zap_count_write(objset_t *os, uint64_t zapobj, const char *name, |
45d1cae3 | 214 | int add, uint64_t *towrite, uint64_t *tooverwrite); |
9babb374 | 215 | |
34dc7c2f BB |
216 | /* |
217 | * Create an attribute with the given name and value. | |
218 | * | |
219 | * If an attribute with the given name already exists, the call will | |
220 | * fail and return EEXIST. | |
221 | */ | |
428870ff | 222 | int zap_add(objset_t *ds, uint64_t zapobj, const char *key, |
34dc7c2f BB |
223 | int integer_size, uint64_t num_integers, |
224 | const void *val, dmu_tx_t *tx); | |
428870ff BB |
225 | int zap_add_uint64(objset_t *ds, uint64_t zapobj, const uint64_t *key, |
226 | int key_numints, int integer_size, uint64_t num_integers, | |
227 | const void *val, dmu_tx_t *tx); | |
34dc7c2f BB |
228 | |
229 | /* | |
230 | * Set the attribute with the given name to the given value. If an | |
231 | * attribute with the given name does not exist, it will be created. If | |
232 | * an attribute with the given name already exists, the previous value | |
233 | * will be overwritten. The integer_size may be different from the | |
234 | * existing attribute's integer size, in which case the attribute's | |
235 | * integer size will be updated to the new value. | |
236 | */ | |
237 | int zap_update(objset_t *ds, uint64_t zapobj, const char *name, | |
238 | int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx); | |
428870ff BB |
239 | int zap_update_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, |
240 | int key_numints, | |
241 | int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx); | |
34dc7c2f BB |
242 | |
243 | /* | |
244 | * Get the length (in integers) and the integer size of the specified | |
245 | * attribute. | |
246 | * | |
247 | * If the requested attribute does not exist, the call will fail and | |
248 | * return ENOENT. | |
249 | */ | |
250 | int zap_length(objset_t *ds, uint64_t zapobj, const char *name, | |
251 | uint64_t *integer_size, uint64_t *num_integers); | |
428870ff BB |
252 | int zap_length_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, |
253 | int key_numints, uint64_t *integer_size, uint64_t *num_integers); | |
34dc7c2f BB |
254 | |
255 | /* | |
256 | * Remove the specified attribute. | |
257 | * | |
258 | * If the specified attribute does not exist, the call will fail and | |
259 | * return ENOENT. | |
260 | */ | |
261 | int zap_remove(objset_t *ds, uint64_t zapobj, const char *name, dmu_tx_t *tx); | |
262 | int zap_remove_norm(objset_t *ds, uint64_t zapobj, const char *name, | |
263 | matchtype_t mt, dmu_tx_t *tx); | |
428870ff BB |
264 | int zap_remove_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key, |
265 | int key_numints, dmu_tx_t *tx); | |
34dc7c2f BB |
266 | |
267 | /* | |
268 | * Returns (in *count) the number of attributes in the specified zap | |
269 | * object. | |
270 | */ | |
271 | int zap_count(objset_t *ds, uint64_t zapobj, uint64_t *count); | |
272 | ||
34dc7c2f BB |
273 | /* |
274 | * Returns (in name) the name of the entry whose (value & mask) | |
275 | * (za_first_integer) is value, or ENOENT if not found. The string | |
276 | * pointed to by name must be at least 256 bytes long. If mask==0, the | |
277 | * match must be exact (ie, same as mask=-1ULL). | |
278 | */ | |
279 | int zap_value_search(objset_t *os, uint64_t zapobj, | |
280 | uint64_t value, uint64_t mask, char *name); | |
281 | ||
b128c09f BB |
282 | /* |
283 | * Transfer all the entries from fromobj into intoobj. Only works on | |
284 | * int_size=8 num_integers=1 values. Fails if there are any duplicated | |
285 | * entries. | |
286 | */ | |
287 | int zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx); | |
288 | ||
428870ff BB |
289 | /* Same as zap_join, but set the values to 'value'. */ |
290 | int zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj, | |
291 | uint64_t value, dmu_tx_t *tx); | |
292 | ||
293 | /* Same as zap_join, but add together any duplicated entries. */ | |
294 | int zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj, | |
295 | dmu_tx_t *tx); | |
296 | ||
b128c09f BB |
297 | /* |
298 | * Manipulate entries where the name + value are the "same" (the name is | |
299 | * a stringified version of the value). | |
300 | */ | |
301 | int zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx); | |
302 | int zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx); | |
303 | int zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value); | |
428870ff BB |
304 | int zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta, |
305 | dmu_tx_t *tx); | |
306 | ||
307 | /* Here the key is an int and the value is a different int. */ | |
308 | int zap_add_int_key(objset_t *os, uint64_t obj, | |
309 | uint64_t key, uint64_t value, dmu_tx_t *tx); | |
753c3839 MA |
310 | int zap_update_int_key(objset_t *os, uint64_t obj, |
311 | uint64_t key, uint64_t value, dmu_tx_t *tx); | |
428870ff BB |
312 | int zap_lookup_int_key(objset_t *os, uint64_t obj, |
313 | uint64_t key, uint64_t *valuep); | |
314 | ||
428870ff BB |
315 | int zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta, |
316 | dmu_tx_t *tx); | |
b128c09f | 317 | |
34dc7c2f BB |
318 | struct zap; |
319 | struct zap_leaf; | |
320 | typedef struct zap_cursor { | |
321 | /* This structure is opaque! */ | |
322 | objset_t *zc_objset; | |
323 | struct zap *zc_zap; | |
324 | struct zap_leaf *zc_leaf; | |
325 | uint64_t zc_zapobj; | |
428870ff | 326 | uint64_t zc_serialized; |
34dc7c2f BB |
327 | uint64_t zc_hash; |
328 | uint32_t zc_cd; | |
329 | } zap_cursor_t; | |
330 | ||
331 | typedef struct { | |
332 | int za_integer_length; | |
333 | /* | |
334 | * za_normalization_conflict will be set if there are additional | |
335 | * entries with this normalized form (eg, "foo" and "Foo"). | |
336 | */ | |
337 | boolean_t za_normalization_conflict; | |
338 | uint64_t za_num_integers; | |
339 | uint64_t za_first_integer; /* no sign extension for <8byte ints */ | |
340 | char za_name[MAXNAMELEN]; | |
341 | } zap_attribute_t; | |
342 | ||
343 | /* | |
344 | * The interface for listing all the attributes of a zapobj can be | |
345 | * thought of as cursor moving down a list of the attributes one by | |
346 | * one. The cookie returned by the zap_cursor_serialize routine is | |
347 | * persistent across system calls (and across reboot, even). | |
348 | */ | |
349 | ||
350 | /* | |
351 | * Initialize a zap cursor, pointing to the "first" attribute of the | |
352 | * zapobj. You must _fini the cursor when you are done with it. | |
353 | */ | |
354 | void zap_cursor_init(zap_cursor_t *zc, objset_t *ds, uint64_t zapobj); | |
355 | void zap_cursor_fini(zap_cursor_t *zc); | |
356 | ||
357 | /* | |
358 | * Get the attribute currently pointed to by the cursor. Returns | |
359 | * ENOENT if at the end of the attributes. | |
360 | */ | |
361 | int zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za); | |
362 | ||
363 | /* | |
364 | * Advance the cursor to the next attribute. | |
365 | */ | |
366 | void zap_cursor_advance(zap_cursor_t *zc); | |
367 | ||
368 | /* | |
369 | * Get a persistent cookie pointing to the current position of the zap | |
370 | * cursor. The low 4 bits in the cookie are always zero, and thus can | |
371 | * be used as to differentiate a serialized cookie from a different type | |
372 | * of value. The cookie will be less than 2^32 as long as there are | |
373 | * fewer than 2^22 (4.2 million) entries in the zap object. | |
374 | */ | |
375 | uint64_t zap_cursor_serialize(zap_cursor_t *zc); | |
376 | ||
428870ff BB |
377 | /* |
378 | * Advance the cursor to the attribute having the given key. | |
379 | */ | |
380 | int zap_cursor_move_to_key(zap_cursor_t *zc, const char *name, matchtype_t mt); | |
381 | ||
34dc7c2f BB |
382 | /* |
383 | * Initialize a zap cursor pointing to the position recorded by | |
384 | * zap_cursor_serialize (in the "serialized" argument). You can also | |
385 | * use a "serialized" argument of 0 to start at the beginning of the | |
386 | * zapobj (ie. zap_cursor_init_serialized(..., 0) is equivalent to | |
387 | * zap_cursor_init(...).) | |
388 | */ | |
389 | void zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *ds, | |
390 | uint64_t zapobj, uint64_t serialized); | |
391 | ||
392 | ||
393 | #define ZAP_HISTOGRAM_SIZE 10 | |
394 | ||
395 | typedef struct zap_stats { | |
396 | /* | |
397 | * Size of the pointer table (in number of entries). | |
398 | * This is always a power of 2, or zero if it's a microzap. | |
399 | * In general, it should be considerably greater than zs_num_leafs. | |
400 | */ | |
401 | uint64_t zs_ptrtbl_len; | |
402 | ||
403 | uint64_t zs_blocksize; /* size of zap blocks */ | |
404 | ||
405 | /* | |
406 | * The number of blocks used. Note that some blocks may be | |
407 | * wasted because old ptrtbl's and large name/value blocks are | |
408 | * not reused. (Although their space is reclaimed, we don't | |
409 | * reuse those offsets in the object.) | |
410 | */ | |
411 | uint64_t zs_num_blocks; | |
412 | ||
413 | /* | |
414 | * Pointer table values from zap_ptrtbl in the zap_phys_t | |
415 | */ | |
416 | uint64_t zs_ptrtbl_nextblk; /* next (larger) copy start block */ | |
417 | uint64_t zs_ptrtbl_blks_copied; /* number source blocks copied */ | |
418 | uint64_t zs_ptrtbl_zt_blk; /* starting block number */ | |
419 | uint64_t zs_ptrtbl_zt_numblks; /* number of blocks */ | |
420 | uint64_t zs_ptrtbl_zt_shift; /* bits to index it */ | |
421 | ||
422 | /* | |
423 | * Values of the other members of the zap_phys_t | |
424 | */ | |
425 | uint64_t zs_block_type; /* ZBT_HEADER */ | |
426 | uint64_t zs_magic; /* ZAP_MAGIC */ | |
427 | uint64_t zs_num_leafs; /* The number of leaf blocks */ | |
428 | uint64_t zs_num_entries; /* The number of zap entries */ | |
429 | uint64_t zs_salt; /* salt to stir into hash function */ | |
430 | ||
431 | /* | |
432 | * Histograms. For all histograms, the last index | |
433 | * (ZAP_HISTOGRAM_SIZE-1) includes any values which are greater | |
434 | * than what can be represented. For example | |
435 | * zs_leafs_with_n5_entries[ZAP_HISTOGRAM_SIZE-1] is the number | |
436 | * of leafs with more than 45 entries. | |
437 | */ | |
438 | ||
439 | /* | |
440 | * zs_leafs_with_n_pointers[n] is the number of leafs with | |
441 | * 2^n pointers to it. | |
442 | */ | |
443 | uint64_t zs_leafs_with_2n_pointers[ZAP_HISTOGRAM_SIZE]; | |
444 | ||
445 | /* | |
446 | * zs_leafs_with_n_entries[n] is the number of leafs with | |
447 | * [n*5, (n+1)*5) entries. In the current implementation, there | |
448 | * can be at most 55 entries in any block, but there may be | |
449 | * fewer if the name or value is large, or the block is not | |
450 | * completely full. | |
451 | */ | |
452 | uint64_t zs_blocks_with_n5_entries[ZAP_HISTOGRAM_SIZE]; | |
453 | ||
454 | /* | |
455 | * zs_leafs_n_tenths_full[n] is the number of leafs whose | |
456 | * fullness is in the range [n/10, (n+1)/10). | |
457 | */ | |
458 | uint64_t zs_blocks_n_tenths_full[ZAP_HISTOGRAM_SIZE]; | |
459 | ||
460 | /* | |
461 | * zs_entries_using_n_chunks[n] is the number of entries which | |
462 | * consume n 24-byte chunks. (Note, large names/values only use | |
463 | * one chunk, but contribute to zs_num_blocks_large.) | |
464 | */ | |
465 | uint64_t zs_entries_using_n_chunks[ZAP_HISTOGRAM_SIZE]; | |
466 | ||
467 | /* | |
468 | * zs_buckets_with_n_entries[n] is the number of buckets (each | |
469 | * leaf has 64 buckets) with n entries. | |
470 | * zs_buckets_with_n_entries[1] should be very close to | |
471 | * zs_num_entries. | |
472 | */ | |
473 | uint64_t zs_buckets_with_n_entries[ZAP_HISTOGRAM_SIZE]; | |
474 | } zap_stats_t; | |
475 | ||
476 | /* | |
477 | * Get statistics about a ZAP object. Note: you need to be aware of the | |
478 | * internal implementation of the ZAP to correctly interpret some of the | |
479 | * statistics. This interface shouldn't be relied on unless you really | |
480 | * know what you're doing. | |
481 | */ | |
482 | int zap_get_stats(objset_t *ds, uint64_t zapobj, zap_stats_t *zs); | |
483 | ||
484 | #ifdef __cplusplus | |
485 | } | |
486 | #endif | |
487 | ||
488 | #endif /* _SYS_ZAP_H */ |