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Allow disabling of unmapped I/O on FreeBSD
[zfs.git] / module / zfs / zap_leaf.c
blobaa6c298c3b4b430872a2c68f0ff1143d00faf69e
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 /*
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
25 * Copyright 2017 Nexenta Systems, Inc.
26 */
27
28 /*
29 * The 512-byte leaf is broken into 32 16-byte chunks.
30 * chunk number n means l_chunk[n], even though the header precedes it.
31 * the names are stored null-terminated.
32 */
33
34 #include <sys/zio.h>
35 #include <sys/spa.h>
36 #include <sys/dmu.h>
37 #include <sys/zfs_context.h>
38 #include <sys/fs/zfs.h>
39 #include <sys/zap.h>
40 #include <sys/zap_impl.h>
41 #include <sys/zap_leaf.h>
42 #include <sys/arc.h>
43
44 static uint16_t *zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry);
45
46 #define CHAIN_END 0xffff /* end of the chunk chain */
47
48 #define LEAF_HASH(l, h) \
49 ((ZAP_LEAF_HASH_NUMENTRIES(l)-1) & \
50 ((h) >> \
51 (64 - ZAP_LEAF_HASH_SHIFT(l) - zap_leaf_phys(l)->l_hdr.lh_prefix_len)))
52
53 #define LEAF_HASH_ENTPTR(l, h) (&zap_leaf_phys(l)->l_hash[LEAF_HASH(l, h)])
54
55 extern inline zap_leaf_phys_t *zap_leaf_phys(zap_leaf_t *l);
56
57 static void
58 zap_memset(void *a, int c, size_t n)
59 {
60 char *cp = a;
61 char *cpend = cp + n;
62
63 while (cp < cpend)
64 *cp++ = c;
65 }
66
67 static void
68 stv(int len, void *addr, uint64_t value)
69 {
70 switch (len) {
71 case 1:
72 *(uint8_t *)addr = value;
73 return;
74 case 2:
75 *(uint16_t *)addr = value;
76 return;
77 case 4:
78 *(uint32_t *)addr = value;
79 return;
80 case 8:
81 *(uint64_t *)addr = value;
82 return;
83 default:
84 cmn_err(CE_PANIC, "bad int len %d", len);
85 }
86 }
87
88 static uint64_t
89 ldv(int len, const void *addr)
90 {
91 switch (len) {
92 case 1:
93 return (*(uint8_t *)addr);
94 case 2:
95 return (*(uint16_t *)addr);
96 case 4:
97 return (*(uint32_t *)addr);
98 case 8:
99 return (*(uint64_t *)addr);
100 default:
101 cmn_err(CE_PANIC, "bad int len %d", len);
102 }
103 return (0xFEEDFACEDEADBEEFULL);
104 }
105
106 void
107 zap_leaf_byteswap(zap_leaf_phys_t *buf, int size)
108 {
109 zap_leaf_t l;
110 dmu_buf_t l_dbuf;
111
112 l_dbuf.db_data = buf;
113 l.l_bs = highbit64(size) - 1;
114 l.l_dbuf = &l_dbuf;
115
116 buf->l_hdr.lh_block_type = BSWAP_64(buf->l_hdr.lh_block_type);
117 buf->l_hdr.lh_prefix = BSWAP_64(buf->l_hdr.lh_prefix);
118 buf->l_hdr.lh_magic = BSWAP_32(buf->l_hdr.lh_magic);
119 buf->l_hdr.lh_nfree = BSWAP_16(buf->l_hdr.lh_nfree);
120 buf->l_hdr.lh_nentries = BSWAP_16(buf->l_hdr.lh_nentries);
121 buf->l_hdr.lh_prefix_len = BSWAP_16(buf->l_hdr.lh_prefix_len);
122 buf->l_hdr.lh_freelist = BSWAP_16(buf->l_hdr.lh_freelist);
123
124 for (int i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++)
125 buf->l_hash[i] = BSWAP_16(buf->l_hash[i]);
126
127 for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
128 zap_leaf_chunk_t *lc = &ZAP_LEAF_CHUNK(&l, i);
129 struct zap_leaf_entry *le;
130
131 switch (lc->l_free.lf_type) {
132 case ZAP_CHUNK_ENTRY:
133 le = &lc->l_entry;
134
135 le->le_type = BSWAP_8(le->le_type);
136 le->le_value_intlen = BSWAP_8(le->le_value_intlen);
137 le->le_next = BSWAP_16(le->le_next);
138 le->le_name_chunk = BSWAP_16(le->le_name_chunk);
139 le->le_name_numints = BSWAP_16(le->le_name_numints);
140 le->le_value_chunk = BSWAP_16(le->le_value_chunk);
141 le->le_value_numints = BSWAP_16(le->le_value_numints);
142 le->le_cd = BSWAP_32(le->le_cd);
143 le->le_hash = BSWAP_64(le->le_hash);
144 break;
145 case ZAP_CHUNK_FREE:
146 lc->l_free.lf_type = BSWAP_8(lc->l_free.lf_type);
147 lc->l_free.lf_next = BSWAP_16(lc->l_free.lf_next);
148 break;
149 case ZAP_CHUNK_ARRAY:
150 lc->l_array.la_type = BSWAP_8(lc->l_array.la_type);
151 lc->l_array.la_next = BSWAP_16(lc->l_array.la_next);
152 /* la_array doesn't need swapping */
153 break;
154 default:
155 cmn_err(CE_PANIC, "bad leaf type %d",
156 lc->l_free.lf_type);
157 }
158 }
159 }
160
161 void
162 zap_leaf_init(zap_leaf_t *l, boolean_t sort)
163 {
164 l->l_bs = highbit64(l->l_dbuf->db_size) - 1;
165 zap_memset(&zap_leaf_phys(l)->l_hdr, 0,
166 sizeof (struct zap_leaf_header));
167 zap_memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
168 2*ZAP_LEAF_HASH_NUMENTRIES(l));
169 for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
170 ZAP_LEAF_CHUNK(l, i).l_free.lf_type = ZAP_CHUNK_FREE;
171 ZAP_LEAF_CHUNK(l, i).l_free.lf_next = i+1;
172 }
173 ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)-1).l_free.lf_next = CHAIN_END;
174 zap_leaf_phys(l)->l_hdr.lh_block_type = ZBT_LEAF;
175 zap_leaf_phys(l)->l_hdr.lh_magic = ZAP_LEAF_MAGIC;
176 zap_leaf_phys(l)->l_hdr.lh_nfree = ZAP_LEAF_NUMCHUNKS(l);
177 if (sort)
178 zap_leaf_phys(l)->l_hdr.lh_flags |= ZLF_ENTRIES_CDSORTED;
179 }
180
181 /*
182 * Routines which manipulate leaf chunks (l_chunk[]).
183 */
184
185 static uint16_t
186 zap_leaf_chunk_alloc(zap_leaf_t *l)
187 {
188 ASSERT(zap_leaf_phys(l)->l_hdr.lh_nfree > 0);
189
190 int chunk = zap_leaf_phys(l)->l_hdr.lh_freelist;
191 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
192 ASSERT3U(ZAP_LEAF_CHUNK(l, chunk).l_free.lf_type, ==, ZAP_CHUNK_FREE);
193
194 zap_leaf_phys(l)->l_hdr.lh_freelist =
195 ZAP_LEAF_CHUNK(l, chunk).l_free.lf_next;
196
197 zap_leaf_phys(l)->l_hdr.lh_nfree--;
198
199 return (chunk);
200 }
201
202 static void
203 zap_leaf_chunk_free(zap_leaf_t *l, uint16_t chunk)
204 {
205 struct zap_leaf_free *zlf = &ZAP_LEAF_CHUNK(l, chunk).l_free;
206 ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_nfree, <, ZAP_LEAF_NUMCHUNKS(l));
207 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
208 ASSERT(zlf->lf_type != ZAP_CHUNK_FREE);
209
210 zlf->lf_type = ZAP_CHUNK_FREE;
211 zlf->lf_next = zap_leaf_phys(l)->l_hdr.lh_freelist;
212 bzero(zlf->lf_pad, sizeof (zlf->lf_pad)); /* help it to compress */
213 zap_leaf_phys(l)->l_hdr.lh_freelist = chunk;
214
215 zap_leaf_phys(l)->l_hdr.lh_nfree++;
216 }
217
218 /*
219 * Routines which manipulate leaf arrays (zap_leaf_array type chunks).
220 */
221
222 static uint16_t
223 zap_leaf_array_create(zap_leaf_t *l, const char *buf,
224 int integer_size, int num_integers)
225 {
226 uint16_t chunk_head;
227 uint16_t *chunkp = &chunk_head;
228 int byten = 0;
229 uint64_t value = 0;
230 int shift = (integer_size - 1) * 8;
231 int len = num_integers;
232
233 ASSERT3U(num_integers * integer_size, <=, ZAP_MAXVALUELEN);
234
235 while (len > 0) {
236 uint16_t chunk = zap_leaf_chunk_alloc(l);
237 struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
238
239 la->la_type = ZAP_CHUNK_ARRAY;
240 for (int i = 0; i < ZAP_LEAF_ARRAY_BYTES; i++) {
241 if (byten == 0)
242 value = ldv(integer_size, buf);
243 la->la_array[i] = value >> shift;
244 value <<= 8;
245 if (++byten == integer_size) {
246 byten = 0;
247 buf += integer_size;
248 if (--len == 0)
249 break;
250 }
251 }
252
253 *chunkp = chunk;
254 chunkp = &la->la_next;
255 }
256 *chunkp = CHAIN_END;
257
258 return (chunk_head);
259 }
260
261 static void
262 zap_leaf_array_free(zap_leaf_t *l, uint16_t *chunkp)
263 {
264 uint16_t chunk = *chunkp;
265
266 *chunkp = CHAIN_END;
267
268 while (chunk != CHAIN_END) {
269 int nextchunk = ZAP_LEAF_CHUNK(l, chunk).l_array.la_next;
270 ASSERT3U(ZAP_LEAF_CHUNK(l, chunk).l_array.la_type, ==,
271 ZAP_CHUNK_ARRAY);
272 zap_leaf_chunk_free(l, chunk);
273 chunk = nextchunk;
274 }
275 }
276
277 /* array_len and buf_len are in integers, not bytes */
278 static void
279 zap_leaf_array_read(zap_leaf_t *l, uint16_t chunk,
280 int array_int_len, int array_len, int buf_int_len, uint64_t buf_len,
281 void *buf)
282 {
283 int len = MIN(array_len, buf_len);
284 int byten = 0;
285 uint64_t value = 0;
286 char *p = buf;
287
288 ASSERT3U(array_int_len, <=, buf_int_len);
289
290 /* Fast path for one 8-byte integer */
291 if (array_int_len == 8 && buf_int_len == 8 && len == 1) {
292 struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
293 uint8_t *ip = la->la_array;
294 uint64_t *buf64 = buf;
295
296 *buf64 = (uint64_t)ip[0] << 56 | (uint64_t)ip[1] << 48 |
297 (uint64_t)ip[2] << 40 | (uint64_t)ip[3] << 32 |
298 (uint64_t)ip[4] << 24 | (uint64_t)ip[5] << 16 |
299 (uint64_t)ip[6] << 8 | (uint64_t)ip[7];
300 return;
301 }
302
303 /* Fast path for an array of 1-byte integers (eg. the entry name) */
304 if (array_int_len == 1 && buf_int_len == 1 &&
305 buf_len > array_len + ZAP_LEAF_ARRAY_BYTES) {
306 while (chunk != CHAIN_END) {
307 struct zap_leaf_array *la =
308 &ZAP_LEAF_CHUNK(l, chunk).l_array;
309 bcopy(la->la_array, p, ZAP_LEAF_ARRAY_BYTES);
310 p += ZAP_LEAF_ARRAY_BYTES;
311 chunk = la->la_next;
312 }
313 return;
314 }
315
316 while (len > 0) {
317 struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
318
319 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
320 for (int i = 0; i < ZAP_LEAF_ARRAY_BYTES && len > 0; i++) {
321 value = (value << 8) | la->la_array[i];
322 byten++;
323 if (byten == array_int_len) {
324 stv(buf_int_len, p, value);
325 byten = 0;
326 len--;
327 if (len == 0)
328 return;
329 p += buf_int_len;
330 }
331 }
332 chunk = la->la_next;
333 }
334 }
335
336 static boolean_t
337 zap_leaf_array_match(zap_leaf_t *l, zap_name_t *zn,
338 int chunk, int array_numints)
339 {
340 int bseen = 0;
341
342 if (zap_getflags(zn->zn_zap) & ZAP_FLAG_UINT64_KEY) {
343 uint64_t *thiskey =
344 kmem_alloc(array_numints * sizeof (*thiskey), KM_SLEEP);
345 ASSERT(zn->zn_key_intlen == sizeof (*thiskey));
346
347 zap_leaf_array_read(l, chunk, sizeof (*thiskey), array_numints,
348 sizeof (*thiskey), array_numints, thiskey);
349 boolean_t match = bcmp(thiskey, zn->zn_key_orig,
350 array_numints * sizeof (*thiskey)) == 0;
351 kmem_free(thiskey, array_numints * sizeof (*thiskey));
352 return (match);
353 }
354
355 ASSERT(zn->zn_key_intlen == 1);
356 if (zn->zn_matchtype & MT_NORMALIZE) {
357 char *thisname = kmem_alloc(array_numints, KM_SLEEP);
358
359 zap_leaf_array_read(l, chunk, sizeof (char), array_numints,
360 sizeof (char), array_numints, thisname);
361 boolean_t match = zap_match(zn, thisname);
362 kmem_free(thisname, array_numints);
363 return (match);
364 }
365
366 /*
367 * Fast path for exact matching.
368 * First check that the lengths match, so that we don't read
369 * past the end of the zn_key_orig array.
370 */
371 if (array_numints != zn->zn_key_orig_numints)
372 return (B_FALSE);
373 while (bseen < array_numints) {
374 struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
375 int toread = MIN(array_numints - bseen, ZAP_LEAF_ARRAY_BYTES);
376 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
377 if (bcmp(la->la_array, (char *)zn->zn_key_orig + bseen, toread))
378 break;
379 chunk = la->la_next;
380 bseen += toread;
381 }
382 return (bseen == array_numints);
383 }
384
385 /*
386 * Routines which manipulate leaf entries.
387 */
388
389 int
390 zap_leaf_lookup(zap_leaf_t *l, zap_name_t *zn, zap_entry_handle_t *zeh)
391 {
392 struct zap_leaf_entry *le;
393
394 ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);
395
396 for (uint16_t *chunkp = LEAF_HASH_ENTPTR(l, zn->zn_hash);
397 *chunkp != CHAIN_END; chunkp = &le->le_next) {
398 uint16_t chunk = *chunkp;
399 le = ZAP_LEAF_ENTRY(l, chunk);
400
401 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
402 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
403
404 if (le->le_hash != zn->zn_hash)
405 continue;
406
407 /*
408 * NB: the entry chain is always sorted by cd on
409 * normalized zap objects, so this will find the
410 * lowest-cd match for MT_NORMALIZE.
411 */
412 ASSERT((zn->zn_matchtype == 0) ||
413 (zap_leaf_phys(l)->l_hdr.lh_flags & ZLF_ENTRIES_CDSORTED));
414 if (zap_leaf_array_match(l, zn, le->le_name_chunk,
415 le->le_name_numints)) {
416 zeh->zeh_num_integers = le->le_value_numints;
417 zeh->zeh_integer_size = le->le_value_intlen;
418 zeh->zeh_cd = le->le_cd;
419 zeh->zeh_hash = le->le_hash;
420 zeh->zeh_chunkp = chunkp;
421 zeh->zeh_leaf = l;
422 return (0);
423 }
424 }
425
426 return (SET_ERROR(ENOENT));
427 }
428
429 /* Return (h1,cd1 >= h2,cd2) */
430 #define HCD_GTEQ(h1, cd1, h2, cd2) \
431 ((h1 > h2) ? TRUE : ((h1 == h2 && cd1 >= cd2) ? TRUE : FALSE))
432
433 int
434 zap_leaf_lookup_closest(zap_leaf_t *l,
435 uint64_t h, uint32_t cd, zap_entry_handle_t *zeh)
436 {
437 uint64_t besth = -1ULL;
438 uint32_t bestcd = -1U;
439 uint16_t bestlh = ZAP_LEAF_HASH_NUMENTRIES(l)-1;
440 struct zap_leaf_entry *le;
441
442 ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);
443
444 for (uint16_t lh = LEAF_HASH(l, h); lh <= bestlh; lh++) {
445 for (uint16_t chunk = zap_leaf_phys(l)->l_hash[lh];
446 chunk != CHAIN_END; chunk = le->le_next) {
447 le = ZAP_LEAF_ENTRY(l, chunk);
448
449 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
450 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
451
452 if (HCD_GTEQ(le->le_hash, le->le_cd, h, cd) &&
453 HCD_GTEQ(besth, bestcd, le->le_hash, le->le_cd)) {
454 ASSERT3U(bestlh, >=, lh);
455 bestlh = lh;
456 besth = le->le_hash;
457 bestcd = le->le_cd;
458
459 zeh->zeh_num_integers = le->le_value_numints;
460 zeh->zeh_integer_size = le->le_value_intlen;
461 zeh->zeh_cd = le->le_cd;
462 zeh->zeh_hash = le->le_hash;
463 zeh->zeh_fakechunk = chunk;
464 zeh->zeh_chunkp = &zeh->zeh_fakechunk;
465 zeh->zeh_leaf = l;
466 }
467 }
468 }
469
470 return (bestcd == -1U ? SET_ERROR(ENOENT) : 0);
471 }
472
473 int
474 zap_entry_read(const zap_entry_handle_t *zeh,
475 uint8_t integer_size, uint64_t num_integers, void *buf)
476 {
477 struct zap_leaf_entry *le =
478 ZAP_LEAF_ENTRY(zeh->zeh_leaf, *zeh->zeh_chunkp);
479 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
480
481 if (le->le_value_intlen > integer_size)
482 return (SET_ERROR(EINVAL));
483
484 zap_leaf_array_read(zeh->zeh_leaf, le->le_value_chunk,
485 le->le_value_intlen, le->le_value_numints,
486 integer_size, num_integers, buf);
487
488 if (zeh->zeh_num_integers > num_integers)
489 return (SET_ERROR(EOVERFLOW));
490 return (0);
491
492 }
493
494 int
495 zap_entry_read_name(zap_t *zap, const zap_entry_handle_t *zeh, uint16_t buflen,
496 char *buf)
497 {
498 struct zap_leaf_entry *le =
499 ZAP_LEAF_ENTRY(zeh->zeh_leaf, *zeh->zeh_chunkp);
500 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
501
502 if (zap_getflags(zap) & ZAP_FLAG_UINT64_KEY) {
503 zap_leaf_array_read(zeh->zeh_leaf, le->le_name_chunk, 8,
504 le->le_name_numints, 8, buflen / 8, buf);
505 } else {
506 zap_leaf_array_read(zeh->zeh_leaf, le->le_name_chunk, 1,
507 le->le_name_numints, 1, buflen, buf);
508 }
509 if (le->le_name_numints > buflen)
510 return (SET_ERROR(EOVERFLOW));
511 return (0);
512 }
513
514 int
515 zap_entry_update(zap_entry_handle_t *zeh,
516 uint8_t integer_size, uint64_t num_integers, const void *buf)
517 {
518 zap_leaf_t *l = zeh->zeh_leaf;
519 struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, *zeh->zeh_chunkp);
520
521 int delta_chunks = ZAP_LEAF_ARRAY_NCHUNKS(num_integers * integer_size) -
522 ZAP_LEAF_ARRAY_NCHUNKS(le->le_value_numints * le->le_value_intlen);
523
524 if ((int)zap_leaf_phys(l)->l_hdr.lh_nfree < delta_chunks)
525 return (SET_ERROR(EAGAIN));
526
527 zap_leaf_array_free(l, &le->le_value_chunk);
528 le->le_value_chunk =
529 zap_leaf_array_create(l, buf, integer_size, num_integers);
530 le->le_value_numints = num_integers;
531 le->le_value_intlen = integer_size;
532 return (0);
533 }
534
535 void
536 zap_entry_remove(zap_entry_handle_t *zeh)
537 {
538 zap_leaf_t *l = zeh->zeh_leaf;
539
540 ASSERT3P(zeh->zeh_chunkp, !=, &zeh->zeh_fakechunk);
541
542 uint16_t entry_chunk = *zeh->zeh_chunkp;
543 struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, entry_chunk);
544 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
545
546 zap_leaf_array_free(l, &le->le_name_chunk);
547 zap_leaf_array_free(l, &le->le_value_chunk);
548
549 *zeh->zeh_chunkp = le->le_next;
550 zap_leaf_chunk_free(l, entry_chunk);
551
552 zap_leaf_phys(l)->l_hdr.lh_nentries--;
553 }
554
555 int
556 zap_entry_create(zap_leaf_t *l, zap_name_t *zn, uint32_t cd,
557 uint8_t integer_size, uint64_t num_integers, const void *buf,
558 zap_entry_handle_t *zeh)
559 {
560 uint16_t chunk;
561 struct zap_leaf_entry *le;
562 uint64_t h = zn->zn_hash;
563
564 uint64_t valuelen = integer_size * num_integers;
565
566 int numchunks = 1 + ZAP_LEAF_ARRAY_NCHUNKS(zn->zn_key_orig_numints *
567 zn->zn_key_intlen) + ZAP_LEAF_ARRAY_NCHUNKS(valuelen);
568 if (numchunks > ZAP_LEAF_NUMCHUNKS(l))
569 return (SET_ERROR(E2BIG));
570
571 if (cd == ZAP_NEED_CD) {
572 /* find the lowest unused cd */
573 if (zap_leaf_phys(l)->l_hdr.lh_flags & ZLF_ENTRIES_CDSORTED) {
574 cd = 0;
575
576 for (chunk = *LEAF_HASH_ENTPTR(l, h);
577 chunk != CHAIN_END; chunk = le->le_next) {
578 le = ZAP_LEAF_ENTRY(l, chunk);
579 if (le->le_cd > cd)
580 break;
581 if (le->le_hash == h) {
582 ASSERT3U(cd, ==, le->le_cd);
583 cd++;
584 }
585 }
586 } else {
587 /* old unsorted format; do it the O(n^2) way */
588 for (cd = 0; ; cd++) {
589 for (chunk = *LEAF_HASH_ENTPTR(l, h);
590 chunk != CHAIN_END; chunk = le->le_next) {
591 le = ZAP_LEAF_ENTRY(l, chunk);
592 if (le->le_hash == h &&
593 le->le_cd == cd) {
594 break;
595 }
596 }
597 /* If this cd is not in use, we are good. */
598 if (chunk == CHAIN_END)
599 break;
600 }
601 }
602 /*
603 * We would run out of space in a block before we could
604 * store enough entries to run out of CD values.
605 */
606 ASSERT3U(cd, <, zap_maxcd(zn->zn_zap));
607 }
608
609 if (zap_leaf_phys(l)->l_hdr.lh_nfree < numchunks)
610 return (SET_ERROR(EAGAIN));
611
612 /* make the entry */
613 chunk = zap_leaf_chunk_alloc(l);
614 le = ZAP_LEAF_ENTRY(l, chunk);
615 le->le_type = ZAP_CHUNK_ENTRY;
616 le->le_name_chunk = zap_leaf_array_create(l, zn->zn_key_orig,
617 zn->zn_key_intlen, zn->zn_key_orig_numints);
618 le->le_name_numints = zn->zn_key_orig_numints;
619 le->le_value_chunk =
620 zap_leaf_array_create(l, buf, integer_size, num_integers);
621 le->le_value_numints = num_integers;
622 le->le_value_intlen = integer_size;
623 le->le_hash = h;
624 le->le_cd = cd;
625
626 /* link it into the hash chain */
627 /* XXX if we did the search above, we could just use that */
628 uint16_t *chunkp = zap_leaf_rehash_entry(l, chunk);
629
630 zap_leaf_phys(l)->l_hdr.lh_nentries++;
631
632 zeh->zeh_leaf = l;
633 zeh->zeh_num_integers = num_integers;
634 zeh->zeh_integer_size = le->le_value_intlen;
635 zeh->zeh_cd = le->le_cd;
636 zeh->zeh_hash = le->le_hash;
637 zeh->zeh_chunkp = chunkp;
638
639 return (0);
640 }
641
642 /*
643 * Determine if there is another entry with the same normalized form.
644 * For performance purposes, either zn or name must be provided (the
645 * other can be NULL). Note, there usually won't be any hash
646 * conflicts, in which case we don't need the concatenated/normalized
647 * form of the name. But all callers have one of these on hand anyway,
648 * so might as well take advantage. A cleaner but slower interface
649 * would accept neither argument, and compute the normalized name as
650 * needed (using zap_name_alloc(zap_entry_read_name(zeh))).
651 */
652 boolean_t
653 zap_entry_normalization_conflict(zap_entry_handle_t *zeh, zap_name_t *zn,
654 const char *name, zap_t *zap)
655 {
656 struct zap_leaf_entry *le;
657 boolean_t allocdzn = B_FALSE;
658
659 if (zap->zap_normflags == 0)
660 return (B_FALSE);
661
662 for (uint16_t chunk = *LEAF_HASH_ENTPTR(zeh->zeh_leaf, zeh->zeh_hash);
663 chunk != CHAIN_END; chunk = le->le_next) {
664 le = ZAP_LEAF_ENTRY(zeh->zeh_leaf, chunk);
665 if (le->le_hash != zeh->zeh_hash)
666 continue;
667 if (le->le_cd == zeh->zeh_cd)
668 continue;
669
670 if (zn == NULL) {
671 zn = zap_name_alloc(zap, name, MT_NORMALIZE);
672 allocdzn = B_TRUE;
673 }
674 if (zap_leaf_array_match(zeh->zeh_leaf, zn,
675 le->le_name_chunk, le->le_name_numints)) {
676 if (allocdzn)
677 zap_name_free(zn);
678 return (B_TRUE);
679 }
680 }
681 if (allocdzn)
682 zap_name_free(zn);
683 return (B_FALSE);
684 }
685
686 /*
687 * Routines for transferring entries between leafs.
688 */
689
690 static uint16_t *
691 zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry)
692 {
693 struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, entry);
694 struct zap_leaf_entry *le2;
695 uint16_t *chunkp;
696
697 /*
698 * keep the entry chain sorted by cd
699 * NB: this will not cause problems for unsorted leafs, though
700 * it is unnecessary there.
701 */
702 for (chunkp = LEAF_HASH_ENTPTR(l, le->le_hash);
703 *chunkp != CHAIN_END; chunkp = &le2->le_next) {
704 le2 = ZAP_LEAF_ENTRY(l, *chunkp);
705 if (le2->le_cd > le->le_cd)
706 break;
707 }
708
709 le->le_next = *chunkp;
710 *chunkp = entry;
711 return (chunkp);
712 }
713
714 static uint16_t
715 zap_leaf_transfer_array(zap_leaf_t *l, uint16_t chunk, zap_leaf_t *nl)
716 {
717 uint16_t new_chunk;
718 uint16_t *nchunkp = &new_chunk;
719
720 while (chunk != CHAIN_END) {
721 uint16_t nchunk = zap_leaf_chunk_alloc(nl);
722 struct zap_leaf_array *nla =
723 &ZAP_LEAF_CHUNK(nl, nchunk).l_array;
724 struct zap_leaf_array *la =
725 &ZAP_LEAF_CHUNK(l, chunk).l_array;
726 int nextchunk = la->la_next;
727
728 ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
729 ASSERT3U(nchunk, <, ZAP_LEAF_NUMCHUNKS(l));
730
731 *nla = *la; /* structure assignment */
732
733 zap_leaf_chunk_free(l, chunk);
734 chunk = nextchunk;
735 *nchunkp = nchunk;
736 nchunkp = &nla->la_next;
737 }
738 *nchunkp = CHAIN_END;
739 return (new_chunk);
740 }
741
742 static void
743 zap_leaf_transfer_entry(zap_leaf_t *l, int entry, zap_leaf_t *nl)
744 {
745 struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, entry);
746 ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
747
748 uint16_t chunk = zap_leaf_chunk_alloc(nl);
749 struct zap_leaf_entry *nle = ZAP_LEAF_ENTRY(nl, chunk);
750 *nle = *le; /* structure assignment */
751
752 (void) zap_leaf_rehash_entry(nl, chunk);
753
754 nle->le_name_chunk = zap_leaf_transfer_array(l, le->le_name_chunk, nl);
755 nle->le_value_chunk =
756 zap_leaf_transfer_array(l, le->le_value_chunk, nl);
757
758 zap_leaf_chunk_free(l, entry);
759
760 zap_leaf_phys(l)->l_hdr.lh_nentries--;
761 zap_leaf_phys(nl)->l_hdr.lh_nentries++;
762 }
763
764 /*
765 * Transfer the entries whose hash prefix ends in 1 to the new leaf.
766 */
767 void
768 zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort)
769 {
770 int bit = 64 - 1 - zap_leaf_phys(l)->l_hdr.lh_prefix_len;
771
772 /* set new prefix and prefix_len */
773 zap_leaf_phys(l)->l_hdr.lh_prefix <<= 1;
774 zap_leaf_phys(l)->l_hdr.lh_prefix_len++;
775 zap_leaf_phys(nl)->l_hdr.lh_prefix =
776 zap_leaf_phys(l)->l_hdr.lh_prefix | 1;
777 zap_leaf_phys(nl)->l_hdr.lh_prefix_len =
778 zap_leaf_phys(l)->l_hdr.lh_prefix_len;
779
780 /* break existing hash chains */
781 zap_memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
782 2*ZAP_LEAF_HASH_NUMENTRIES(l));
783
784 if (sort)
785 zap_leaf_phys(l)->l_hdr.lh_flags |= ZLF_ENTRIES_CDSORTED;
786
787 /*
788 * Transfer entries whose hash bit 'bit' is set to nl; rehash
789 * the remaining entries
790 *
791 * NB: We could find entries via the hashtable instead. That
792 * would be O(hashents+numents) rather than O(numblks+numents),
793 * but this accesses memory more sequentially, and when we're
794 * called, the block is usually pretty full.
795 */
796 for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
797 struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, i);
798 if (le->le_type != ZAP_CHUNK_ENTRY)
799 continue;
800
801 if (le->le_hash & (1ULL << bit))
802 zap_leaf_transfer_entry(l, i, nl);
803 else
804 (void) zap_leaf_rehash_entry(l, i);
805 }
806 }
807
808 void
809 zap_leaf_stats(zap_t *zap, zap_leaf_t *l, zap_stats_t *zs)
810 {
811 int n = zap_f_phys(zap)->zap_ptrtbl.zt_shift -
812 zap_leaf_phys(l)->l_hdr.lh_prefix_len;
813 n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
814 zs->zs_leafs_with_2n_pointers[n]++;
815
816
817 n = zap_leaf_phys(l)->l_hdr.lh_nentries/5;
818 n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
819 zs->zs_blocks_with_n5_entries[n]++;
820
821 n = ((1<<FZAP_BLOCK_SHIFT(zap)) -
822 zap_leaf_phys(l)->l_hdr.lh_nfree * (ZAP_LEAF_ARRAY_BYTES+1))*10 /
823 (1<<FZAP_BLOCK_SHIFT(zap));
824 n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
825 zs->zs_blocks_n_tenths_full[n]++;
826
827 for (int i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(l); i++) {
828 int nentries = 0;
829 int chunk = zap_leaf_phys(l)->l_hash[i];
830
831 while (chunk != CHAIN_END) {
832 struct zap_leaf_entry *le =
833 ZAP_LEAF_ENTRY(l, chunk);
834
835 n = 1 + ZAP_LEAF_ARRAY_NCHUNKS(le->le_name_numints) +
836 ZAP_LEAF_ARRAY_NCHUNKS(le->le_value_numints *
837 le->le_value_intlen);
838 n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
839 zs->zs_entries_using_n_chunks[n]++;
840
841 chunk = le->le_next;
842 nentries++;
843 }
844
845 n = nentries;
846 n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
847 zs->zs_buckets_with_n_entries[n]++;
848 }
849 }
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