xref: /titanic_41/usr/src/uts/common/fs/zfs/zap_micro.c (revision c4cb95767ae6931f185dc5c02edb165c2ff75b10)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25  */
26 
27 #include <sys/zio.h>
28 #include <sys/spa.h>
29 #include <sys/dmu.h>
30 #include <sys/zfs_context.h>
31 #include <sys/zap.h>
32 #include <sys/refcount.h>
33 #include <sys/zap_impl.h>
34 #include <sys/zap_leaf.h>
35 #include <sys/avl.h>
36 #include <sys/arc.h>
37 #include <sys/dmu_objset.h>
38 
39 #ifdef _KERNEL
40 #include <sys/sunddi.h>
41 #endif
42 
43 extern inline mzap_phys_t *zap_m_phys(zap_t *zap);
44 
45 static int mzap_upgrade(zap_t **zapp, dmu_tx_t *tx, zap_flags_t flags);
46 
47 uint64_t
zap_getflags(zap_t * zap)48 zap_getflags(zap_t *zap)
49 {
50 	if (zap->zap_ismicro)
51 		return (0);
52 	return (zap_f_phys(zap)->zap_flags);
53 }
54 
55 int
zap_hashbits(zap_t * zap)56 zap_hashbits(zap_t *zap)
57 {
58 	if (zap_getflags(zap) & ZAP_FLAG_HASH64)
59 		return (48);
60 	else
61 		return (28);
62 }
63 
64 uint32_t
zap_maxcd(zap_t * zap)65 zap_maxcd(zap_t *zap)
66 {
67 	if (zap_getflags(zap) & ZAP_FLAG_HASH64)
68 		return ((1<<16)-1);
69 	else
70 		return (-1U);
71 }
72 
73 static uint64_t
zap_hash(zap_name_t * zn)74 zap_hash(zap_name_t *zn)
75 {
76 	zap_t *zap = zn->zn_zap;
77 	uint64_t h = 0;
78 
79 	if (zap_getflags(zap) & ZAP_FLAG_PRE_HASHED_KEY) {
80 		ASSERT(zap_getflags(zap) & ZAP_FLAG_UINT64_KEY);
81 		h = *(uint64_t *)zn->zn_key_orig;
82 	} else {
83 		h = zap->zap_salt;
84 		ASSERT(h != 0);
85 		ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY);
86 
87 		if (zap_getflags(zap) & ZAP_FLAG_UINT64_KEY) {
88 			int i;
89 			const uint64_t *wp = zn->zn_key_norm;
90 
91 			ASSERT(zn->zn_key_intlen == 8);
92 			for (i = 0; i < zn->zn_key_norm_numints; wp++, i++) {
93 				int j;
94 				uint64_t word = *wp;
95 
96 				for (j = 0; j < zn->zn_key_intlen; j++) {
97 					h = (h >> 8) ^
98 					    zfs_crc64_table[(h ^ word) & 0xFF];
99 					word >>= NBBY;
100 				}
101 			}
102 		} else {
103 			int i, len;
104 			const uint8_t *cp = zn->zn_key_norm;
105 
106 			/*
107 			 * We previously stored the terminating null on
108 			 * disk, but didn't hash it, so we need to
109 			 * continue to not hash it.  (The
110 			 * zn_key_*_numints includes the terminating
111 			 * null for non-binary keys.)
112 			 */
113 			len = zn->zn_key_norm_numints - 1;
114 
115 			ASSERT(zn->zn_key_intlen == 1);
116 			for (i = 0; i < len; cp++, i++) {
117 				h = (h >> 8) ^
118 				    zfs_crc64_table[(h ^ *cp) & 0xFF];
119 			}
120 		}
121 	}
122 	/*
123 	 * Don't use all 64 bits, since we need some in the cookie for
124 	 * the collision differentiator.  We MUST use the high bits,
125 	 * since those are the ones that we first pay attention to when
126 	 * chosing the bucket.
127 	 */
128 	h &= ~((1ULL << (64 - zap_hashbits(zap))) - 1);
129 
130 	return (h);
131 }
132 
133 static int
zap_normalize(zap_t * zap,const char * name,char * namenorm)134 zap_normalize(zap_t *zap, const char *name, char *namenorm)
135 {
136 	size_t inlen, outlen;
137 	int err;
138 
139 	ASSERT(!(zap_getflags(zap) & ZAP_FLAG_UINT64_KEY));
140 
141 	inlen = strlen(name) + 1;
142 	outlen = ZAP_MAXNAMELEN;
143 
144 	err = 0;
145 	(void) u8_textprep_str((char *)name, &inlen, namenorm, &outlen,
146 	    zap->zap_normflags | U8_TEXTPREP_IGNORE_NULL |
147 	    U8_TEXTPREP_IGNORE_INVALID, U8_UNICODE_LATEST, &err);
148 
149 	return (err);
150 }
151 
152 boolean_t
zap_match(zap_name_t * zn,const char * matchname)153 zap_match(zap_name_t *zn, const char *matchname)
154 {
155 	ASSERT(!(zap_getflags(zn->zn_zap) & ZAP_FLAG_UINT64_KEY));
156 
157 	if (zn->zn_matchtype == MT_FIRST) {
158 		char norm[ZAP_MAXNAMELEN];
159 
160 		if (zap_normalize(zn->zn_zap, matchname, norm) != 0)
161 			return (B_FALSE);
162 
163 		return (strcmp(zn->zn_key_norm, norm) == 0);
164 	} else {
165 		/* MT_BEST or MT_EXACT */
166 		return (strcmp(zn->zn_key_orig, matchname) == 0);
167 	}
168 }
169 
170 void
zap_name_free(zap_name_t * zn)171 zap_name_free(zap_name_t *zn)
172 {
173 	kmem_free(zn, sizeof (zap_name_t));
174 }
175 
176 zap_name_t *
zap_name_alloc(zap_t * zap,const char * key,matchtype_t mt)177 zap_name_alloc(zap_t *zap, const char *key, matchtype_t mt)
178 {
179 	zap_name_t *zn = kmem_alloc(sizeof (zap_name_t), KM_SLEEP);
180 
181 	zn->zn_zap = zap;
182 	zn->zn_key_intlen = sizeof (*key);
183 	zn->zn_key_orig = key;
184 	zn->zn_key_orig_numints = strlen(zn->zn_key_orig) + 1;
185 	zn->zn_matchtype = mt;
186 	if (zap->zap_normflags) {
187 		if (zap_normalize(zap, key, zn->zn_normbuf) != 0) {
188 			zap_name_free(zn);
189 			return (NULL);
190 		}
191 		zn->zn_key_norm = zn->zn_normbuf;
192 		zn->zn_key_norm_numints = strlen(zn->zn_key_norm) + 1;
193 	} else {
194 		if (mt != MT_EXACT) {
195 			zap_name_free(zn);
196 			return (NULL);
197 		}
198 		zn->zn_key_norm = zn->zn_key_orig;
199 		zn->zn_key_norm_numints = zn->zn_key_orig_numints;
200 	}
201 
202 	zn->zn_hash = zap_hash(zn);
203 	return (zn);
204 }
205 
206 zap_name_t *
zap_name_alloc_uint64(zap_t * zap,const uint64_t * key,int numints)207 zap_name_alloc_uint64(zap_t *zap, const uint64_t *key, int numints)
208 {
209 	zap_name_t *zn = kmem_alloc(sizeof (zap_name_t), KM_SLEEP);
210 
211 	ASSERT(zap->zap_normflags == 0);
212 	zn->zn_zap = zap;
213 	zn->zn_key_intlen = sizeof (*key);
214 	zn->zn_key_orig = zn->zn_key_norm = key;
215 	zn->zn_key_orig_numints = zn->zn_key_norm_numints = numints;
216 	zn->zn_matchtype = MT_EXACT;
217 
218 	zn->zn_hash = zap_hash(zn);
219 	return (zn);
220 }
221 
222 static void
mzap_byteswap(mzap_phys_t * buf,size_t size)223 mzap_byteswap(mzap_phys_t *buf, size_t size)
224 {
225 	int i, max;
226 	buf->mz_block_type = BSWAP_64(buf->mz_block_type);
227 	buf->mz_salt = BSWAP_64(buf->mz_salt);
228 	buf->mz_normflags = BSWAP_64(buf->mz_normflags);
229 	max = (size / MZAP_ENT_LEN) - 1;
230 	for (i = 0; i < max; i++) {
231 		buf->mz_chunk[i].mze_value =
232 		    BSWAP_64(buf->mz_chunk[i].mze_value);
233 		buf->mz_chunk[i].mze_cd =
234 		    BSWAP_32(buf->mz_chunk[i].mze_cd);
235 	}
236 }
237 
238 void
zap_byteswap(void * buf,size_t size)239 zap_byteswap(void *buf, size_t size)
240 {
241 	uint64_t block_type;
242 
243 	block_type = *(uint64_t *)buf;
244 
245 	if (block_type == ZBT_MICRO || block_type == BSWAP_64(ZBT_MICRO)) {
246 		/* ASSERT(magic == ZAP_LEAF_MAGIC); */
247 		mzap_byteswap(buf, size);
248 	} else {
249 		fzap_byteswap(buf, size);
250 	}
251 }
252 
253 static int
mze_compare(const void * arg1,const void * arg2)254 mze_compare(const void *arg1, const void *arg2)
255 {
256 	const mzap_ent_t *mze1 = arg1;
257 	const mzap_ent_t *mze2 = arg2;
258 
259 	if (mze1->mze_hash > mze2->mze_hash)
260 		return (+1);
261 	if (mze1->mze_hash < mze2->mze_hash)
262 		return (-1);
263 	if (mze1->mze_cd > mze2->mze_cd)
264 		return (+1);
265 	if (mze1->mze_cd < mze2->mze_cd)
266 		return (-1);
267 	return (0);
268 }
269 
270 static void
mze_insert(zap_t * zap,int chunkid,uint64_t hash)271 mze_insert(zap_t *zap, int chunkid, uint64_t hash)
272 {
273 	mzap_ent_t *mze;
274 
275 	ASSERT(zap->zap_ismicro);
276 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
277 
278 	mze = kmem_alloc(sizeof (mzap_ent_t), KM_SLEEP);
279 	mze->mze_chunkid = chunkid;
280 	mze->mze_hash = hash;
281 	mze->mze_cd = MZE_PHYS(zap, mze)->mze_cd;
282 	ASSERT(MZE_PHYS(zap, mze)->mze_name[0] != 0);
283 	avl_add(&zap->zap_m.zap_avl, mze);
284 }
285 
286 static mzap_ent_t *
mze_find(zap_name_t * zn)287 mze_find(zap_name_t *zn)
288 {
289 	mzap_ent_t mze_tofind;
290 	mzap_ent_t *mze;
291 	avl_index_t idx;
292 	avl_tree_t *avl = &zn->zn_zap->zap_m.zap_avl;
293 
294 	ASSERT(zn->zn_zap->zap_ismicro);
295 	ASSERT(RW_LOCK_HELD(&zn->zn_zap->zap_rwlock));
296 
297 	mze_tofind.mze_hash = zn->zn_hash;
298 	mze_tofind.mze_cd = 0;
299 
300 again:
301 	mze = avl_find(avl, &mze_tofind, &idx);
302 	if (mze == NULL)
303 		mze = avl_nearest(avl, idx, AVL_AFTER);
304 	for (; mze && mze->mze_hash == zn->zn_hash; mze = AVL_NEXT(avl, mze)) {
305 		ASSERT3U(mze->mze_cd, ==, MZE_PHYS(zn->zn_zap, mze)->mze_cd);
306 		if (zap_match(zn, MZE_PHYS(zn->zn_zap, mze)->mze_name))
307 			return (mze);
308 	}
309 	if (zn->zn_matchtype == MT_BEST) {
310 		zn->zn_matchtype = MT_FIRST;
311 		goto again;
312 	}
313 	return (NULL);
314 }
315 
316 static uint32_t
mze_find_unused_cd(zap_t * zap,uint64_t hash)317 mze_find_unused_cd(zap_t *zap, uint64_t hash)
318 {
319 	mzap_ent_t mze_tofind;
320 	mzap_ent_t *mze;
321 	avl_index_t idx;
322 	avl_tree_t *avl = &zap->zap_m.zap_avl;
323 	uint32_t cd;
324 
325 	ASSERT(zap->zap_ismicro);
326 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
327 
328 	mze_tofind.mze_hash = hash;
329 	mze_tofind.mze_cd = 0;
330 
331 	cd = 0;
332 	for (mze = avl_find(avl, &mze_tofind, &idx);
333 	    mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) {
334 		if (mze->mze_cd != cd)
335 			break;
336 		cd++;
337 	}
338 
339 	return (cd);
340 }
341 
342 static void
mze_remove(zap_t * zap,mzap_ent_t * mze)343 mze_remove(zap_t *zap, mzap_ent_t *mze)
344 {
345 	ASSERT(zap->zap_ismicro);
346 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
347 
348 	avl_remove(&zap->zap_m.zap_avl, mze);
349 	kmem_free(mze, sizeof (mzap_ent_t));
350 }
351 
352 static void
mze_destroy(zap_t * zap)353 mze_destroy(zap_t *zap)
354 {
355 	mzap_ent_t *mze;
356 	void *avlcookie = NULL;
357 
358 	while (mze = avl_destroy_nodes(&zap->zap_m.zap_avl, &avlcookie))
359 		kmem_free(mze, sizeof (mzap_ent_t));
360 	avl_destroy(&zap->zap_m.zap_avl);
361 }
362 
363 static zap_t *
mzap_open(objset_t * os,uint64_t obj,dmu_buf_t * db)364 mzap_open(objset_t *os, uint64_t obj, dmu_buf_t *db)
365 {
366 	zap_t *winner;
367 	zap_t *zap;
368 	int i;
369 
370 	ASSERT3U(MZAP_ENT_LEN, ==, sizeof (mzap_ent_phys_t));
371 
372 	zap = kmem_zalloc(sizeof (zap_t), KM_SLEEP);
373 	rw_init(&zap->zap_rwlock, 0, 0, 0);
374 	rw_enter(&zap->zap_rwlock, RW_WRITER);
375 	zap->zap_objset = os;
376 	zap->zap_object = obj;
377 	zap->zap_dbuf = db;
378 
379 	if (*(uint64_t *)db->db_data != ZBT_MICRO) {
380 		mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0);
381 		zap->zap_f.zap_block_shift = highbit64(db->db_size) - 1;
382 	} else {
383 		zap->zap_ismicro = TRUE;
384 	}
385 
386 	/*
387 	 * Make sure that zap_ismicro is set before we let others see
388 	 * it, because zap_lockdir() checks zap_ismicro without the lock
389 	 * held.
390 	 */
391 	dmu_buf_init_user(&zap->zap_dbu, zap_evict_sync, NULL, &zap->zap_dbuf);
392 	winner = dmu_buf_set_user(db, &zap->zap_dbu);
393 
394 	if (winner != NULL) {
395 		rw_exit(&zap->zap_rwlock);
396 		rw_destroy(&zap->zap_rwlock);
397 		if (!zap->zap_ismicro)
398 			mutex_destroy(&zap->zap_f.zap_num_entries_mtx);
399 		kmem_free(zap, sizeof (zap_t));
400 		return (winner);
401 	}
402 
403 	if (zap->zap_ismicro) {
404 		zap->zap_salt = zap_m_phys(zap)->mz_salt;
405 		zap->zap_normflags = zap_m_phys(zap)->mz_normflags;
406 		zap->zap_m.zap_num_chunks = db->db_size / MZAP_ENT_LEN - 1;
407 		avl_create(&zap->zap_m.zap_avl, mze_compare,
408 		    sizeof (mzap_ent_t), offsetof(mzap_ent_t, mze_node));
409 
410 		for (i = 0; i < zap->zap_m.zap_num_chunks; i++) {
411 			mzap_ent_phys_t *mze =
412 			    &zap_m_phys(zap)->mz_chunk[i];
413 			if (mze->mze_name[0]) {
414 				zap_name_t *zn;
415 
416 				zap->zap_m.zap_num_entries++;
417 				zn = zap_name_alloc(zap, mze->mze_name,
418 				    MT_EXACT);
419 				mze_insert(zap, i, zn->zn_hash);
420 				zap_name_free(zn);
421 			}
422 		}
423 	} else {
424 		zap->zap_salt = zap_f_phys(zap)->zap_salt;
425 		zap->zap_normflags = zap_f_phys(zap)->zap_normflags;
426 
427 		ASSERT3U(sizeof (struct zap_leaf_header), ==,
428 		    2*ZAP_LEAF_CHUNKSIZE);
429 
430 		/*
431 		 * The embedded pointer table should not overlap the
432 		 * other members.
433 		 */
434 		ASSERT3P(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), >,
435 		    &zap_f_phys(zap)->zap_salt);
436 
437 		/*
438 		 * The embedded pointer table should end at the end of
439 		 * the block
440 		 */
441 		ASSERT3U((uintptr_t)&ZAP_EMBEDDED_PTRTBL_ENT(zap,
442 		    1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)) -
443 		    (uintptr_t)zap_f_phys(zap), ==,
444 		    zap->zap_dbuf->db_size);
445 	}
446 	rw_exit(&zap->zap_rwlock);
447 	return (zap);
448 }
449 
450 int
zap_lockdir(objset_t * os,uint64_t obj,dmu_tx_t * tx,krw_t lti,boolean_t fatreader,boolean_t adding,zap_t ** zapp)451 zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx,
452     krw_t lti, boolean_t fatreader, boolean_t adding, zap_t **zapp)
453 {
454 	zap_t *zap;
455 	dmu_buf_t *db;
456 	krw_t lt;
457 	int err;
458 
459 	*zapp = NULL;
460 
461 	err = dmu_buf_hold(os, obj, 0, NULL, &db, DMU_READ_NO_PREFETCH);
462 	if (err)
463 		return (err);
464 
465 #ifdef ZFS_DEBUG
466 	{
467 		dmu_object_info_t doi;
468 		dmu_object_info_from_db(db, &doi);
469 		ASSERT3U(DMU_OT_BYTESWAP(doi.doi_type), ==, DMU_BSWAP_ZAP);
470 	}
471 #endif
472 
473 	zap = dmu_buf_get_user(db);
474 	if (zap == NULL)
475 		zap = mzap_open(os, obj, db);
476 
477 	/*
478 	 * We're checking zap_ismicro without the lock held, in order to
479 	 * tell what type of lock we want.  Once we have some sort of
480 	 * lock, see if it really is the right type.  In practice this
481 	 * can only be different if it was upgraded from micro to fat,
482 	 * and micro wanted WRITER but fat only needs READER.
483 	 */
484 	lt = (!zap->zap_ismicro && fatreader) ? RW_READER : lti;
485 	rw_enter(&zap->zap_rwlock, lt);
486 	if (lt != ((!zap->zap_ismicro && fatreader) ? RW_READER : lti)) {
487 		/* it was upgraded, now we only need reader */
488 		ASSERT(lt == RW_WRITER);
489 		ASSERT(RW_READER ==
490 		    (!zap->zap_ismicro && fatreader) ? RW_READER : lti);
491 		rw_downgrade(&zap->zap_rwlock);
492 		lt = RW_READER;
493 	}
494 
495 	zap->zap_objset = os;
496 
497 	if (lt == RW_WRITER)
498 		dmu_buf_will_dirty(db, tx);
499 
500 	ASSERT3P(zap->zap_dbuf, ==, db);
501 
502 	ASSERT(!zap->zap_ismicro ||
503 	    zap->zap_m.zap_num_entries <= zap->zap_m.zap_num_chunks);
504 	if (zap->zap_ismicro && tx && adding &&
505 	    zap->zap_m.zap_num_entries == zap->zap_m.zap_num_chunks) {
506 		uint64_t newsz = db->db_size + SPA_MINBLOCKSIZE;
507 		if (newsz > MZAP_MAX_BLKSZ) {
508 			dprintf("upgrading obj %llu: num_entries=%u\n",
509 			    obj, zap->zap_m.zap_num_entries);
510 			*zapp = zap;
511 			return (mzap_upgrade(zapp, tx, 0));
512 		}
513 		err = dmu_object_set_blocksize(os, obj, newsz, 0, tx);
514 		ASSERT0(err);
515 		zap->zap_m.zap_num_chunks =
516 		    db->db_size / MZAP_ENT_LEN - 1;
517 	}
518 
519 	*zapp = zap;
520 	return (0);
521 }
522 
523 void
zap_unlockdir(zap_t * zap)524 zap_unlockdir(zap_t *zap)
525 {
526 	rw_exit(&zap->zap_rwlock);
527 	dmu_buf_rele(zap->zap_dbuf, NULL);
528 }
529 
530 static int
mzap_upgrade(zap_t ** zapp,dmu_tx_t * tx,zap_flags_t flags)531 mzap_upgrade(zap_t **zapp, dmu_tx_t *tx, zap_flags_t flags)
532 {
533 	mzap_phys_t *mzp;
534 	int i, sz, nchunks;
535 	int err = 0;
536 	zap_t *zap = *zapp;
537 
538 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
539 
540 	sz = zap->zap_dbuf->db_size;
541 	mzp = zio_buf_alloc(sz);
542 	bcopy(zap->zap_dbuf->db_data, mzp, sz);
543 	nchunks = zap->zap_m.zap_num_chunks;
544 
545 	if (!flags) {
546 		err = dmu_object_set_blocksize(zap->zap_objset, zap->zap_object,
547 		    1ULL << fzap_default_block_shift, 0, tx);
548 		if (err) {
549 			zio_buf_free(mzp, sz);
550 			return (err);
551 		}
552 	}
553 
554 	dprintf("upgrading obj=%llu with %u chunks\n",
555 	    zap->zap_object, nchunks);
556 	/* XXX destroy the avl later, so we can use the stored hash value */
557 	mze_destroy(zap);
558 
559 	fzap_upgrade(zap, tx, flags);
560 
561 	for (i = 0; i < nchunks; i++) {
562 		mzap_ent_phys_t *mze = &mzp->mz_chunk[i];
563 		zap_name_t *zn;
564 		if (mze->mze_name[0] == 0)
565 			continue;
566 		dprintf("adding %s=%llu\n",
567 		    mze->mze_name, mze->mze_value);
568 		zn = zap_name_alloc(zap, mze->mze_name, MT_EXACT);
569 		err = fzap_add_cd(zn, 8, 1, &mze->mze_value, mze->mze_cd, tx);
570 		zap = zn->zn_zap;	/* fzap_add_cd() may change zap */
571 		zap_name_free(zn);
572 		if (err)
573 			break;
574 	}
575 	zio_buf_free(mzp, sz);
576 	*zapp = zap;
577 	return (err);
578 }
579 
580 void
mzap_create_impl(objset_t * os,uint64_t obj,int normflags,zap_flags_t flags,dmu_tx_t * tx)581 mzap_create_impl(objset_t *os, uint64_t obj, int normflags, zap_flags_t flags,
582     dmu_tx_t *tx)
583 {
584 	dmu_buf_t *db;
585 	mzap_phys_t *zp;
586 
587 	VERIFY(0 == dmu_buf_hold(os, obj, 0, FTAG, &db, DMU_READ_NO_PREFETCH));
588 
589 #ifdef ZFS_DEBUG
590 	{
591 		dmu_object_info_t doi;
592 		dmu_object_info_from_db(db, &doi);
593 		ASSERT3U(DMU_OT_BYTESWAP(doi.doi_type), ==, DMU_BSWAP_ZAP);
594 	}
595 #endif
596 
597 	dmu_buf_will_dirty(db, tx);
598 	zp = db->db_data;
599 	zp->mz_block_type = ZBT_MICRO;
600 	zp->mz_salt = ((uintptr_t)db ^ (uintptr_t)tx ^ (obj << 1)) | 1ULL;
601 	zp->mz_normflags = normflags;
602 	dmu_buf_rele(db, FTAG);
603 
604 	if (flags != 0) {
605 		zap_t *zap;
606 		/* Only fat zap supports flags; upgrade immediately. */
607 		VERIFY(0 == zap_lockdir(os, obj, tx, RW_WRITER,
608 		    B_FALSE, B_FALSE, &zap));
609 		VERIFY3U(0, ==, mzap_upgrade(&zap, tx, flags));
610 		zap_unlockdir(zap);
611 	}
612 }
613 
614 int
zap_create_claim(objset_t * os,uint64_t obj,dmu_object_type_t ot,dmu_object_type_t bonustype,int bonuslen,dmu_tx_t * tx)615 zap_create_claim(objset_t *os, uint64_t obj, dmu_object_type_t ot,
616     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
617 {
618 	return (zap_create_claim_norm(os, obj,
619 	    0, ot, bonustype, bonuslen, tx));
620 }
621 
622 int
zap_create_claim_norm(objset_t * os,uint64_t obj,int normflags,dmu_object_type_t ot,dmu_object_type_t bonustype,int bonuslen,dmu_tx_t * tx)623 zap_create_claim_norm(objset_t *os, uint64_t obj, int normflags,
624     dmu_object_type_t ot,
625     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
626 {
627 	int err;
628 
629 	err = dmu_object_claim(os, obj, ot, 0, bonustype, bonuslen, tx);
630 	if (err != 0)
631 		return (err);
632 	mzap_create_impl(os, obj, normflags, 0, tx);
633 	return (0);
634 }
635 
636 uint64_t
zap_create(objset_t * os,dmu_object_type_t ot,dmu_object_type_t bonustype,int bonuslen,dmu_tx_t * tx)637 zap_create(objset_t *os, dmu_object_type_t ot,
638     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
639 {
640 	return (zap_create_norm(os, 0, ot, bonustype, bonuslen, tx));
641 }
642 
643 uint64_t
zap_create_norm(objset_t * os,int normflags,dmu_object_type_t ot,dmu_object_type_t bonustype,int bonuslen,dmu_tx_t * tx)644 zap_create_norm(objset_t *os, int normflags, dmu_object_type_t ot,
645     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
646 {
647 	uint64_t obj = dmu_object_alloc(os, ot, 0, bonustype, bonuslen, tx);
648 
649 	mzap_create_impl(os, obj, normflags, 0, tx);
650 	return (obj);
651 }
652 
653 uint64_t
zap_create_flags(objset_t * os,int normflags,zap_flags_t flags,dmu_object_type_t ot,int leaf_blockshift,int indirect_blockshift,dmu_object_type_t bonustype,int bonuslen,dmu_tx_t * tx)654 zap_create_flags(objset_t *os, int normflags, zap_flags_t flags,
655     dmu_object_type_t ot, int leaf_blockshift, int indirect_blockshift,
656     dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx)
657 {
658 	uint64_t obj = dmu_object_alloc(os, ot, 0, bonustype, bonuslen, tx);
659 
660 	ASSERT(leaf_blockshift >= SPA_MINBLOCKSHIFT &&
661 	    leaf_blockshift <= SPA_OLD_MAXBLOCKSHIFT &&
662 	    indirect_blockshift >= SPA_MINBLOCKSHIFT &&
663 	    indirect_blockshift <= SPA_OLD_MAXBLOCKSHIFT);
664 
665 	VERIFY(dmu_object_set_blocksize(os, obj,
666 	    1ULL << leaf_blockshift, indirect_blockshift, tx) == 0);
667 
668 	mzap_create_impl(os, obj, normflags, flags, tx);
669 	return (obj);
670 }
671 
672 int
zap_destroy(objset_t * os,uint64_t zapobj,dmu_tx_t * tx)673 zap_destroy(objset_t *os, uint64_t zapobj, dmu_tx_t *tx)
674 {
675 	/*
676 	 * dmu_object_free will free the object number and free the
677 	 * data.  Freeing the data will cause our pageout function to be
678 	 * called, which will destroy our data (zap_leaf_t's and zap_t).
679 	 */
680 
681 	return (dmu_object_free(os, zapobj, tx));
682 }
683 
684 void
zap_evict_sync(void * dbu)685 zap_evict_sync(void *dbu)
686 {
687 	zap_t *zap = dbu;
688 
689 	rw_destroy(&zap->zap_rwlock);
690 
691 	if (zap->zap_ismicro)
692 		mze_destroy(zap);
693 	else
694 		mutex_destroy(&zap->zap_f.zap_num_entries_mtx);
695 
696 	kmem_free(zap, sizeof (zap_t));
697 }
698 
699 int
zap_count(objset_t * os,uint64_t zapobj,uint64_t * count)700 zap_count(objset_t *os, uint64_t zapobj, uint64_t *count)
701 {
702 	zap_t *zap;
703 	int err;
704 
705 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
706 	if (err)
707 		return (err);
708 	if (!zap->zap_ismicro) {
709 		err = fzap_count(zap, count);
710 	} else {
711 		*count = zap->zap_m.zap_num_entries;
712 	}
713 	zap_unlockdir(zap);
714 	return (err);
715 }
716 
717 /*
718  * zn may be NULL; if not specified, it will be computed if needed.
719  * See also the comment above zap_entry_normalization_conflict().
720  */
721 static boolean_t
mzap_normalization_conflict(zap_t * zap,zap_name_t * zn,mzap_ent_t * mze)722 mzap_normalization_conflict(zap_t *zap, zap_name_t *zn, mzap_ent_t *mze)
723 {
724 	mzap_ent_t *other;
725 	int direction = AVL_BEFORE;
726 	boolean_t allocdzn = B_FALSE;
727 
728 	if (zap->zap_normflags == 0)
729 		return (B_FALSE);
730 
731 again:
732 	for (other = avl_walk(&zap->zap_m.zap_avl, mze, direction);
733 	    other && other->mze_hash == mze->mze_hash;
734 	    other = avl_walk(&zap->zap_m.zap_avl, other, direction)) {
735 
736 		if (zn == NULL) {
737 			zn = zap_name_alloc(zap, MZE_PHYS(zap, mze)->mze_name,
738 			    MT_FIRST);
739 			allocdzn = B_TRUE;
740 		}
741 		if (zap_match(zn, MZE_PHYS(zap, other)->mze_name)) {
742 			if (allocdzn)
743 				zap_name_free(zn);
744 			return (B_TRUE);
745 		}
746 	}
747 
748 	if (direction == AVL_BEFORE) {
749 		direction = AVL_AFTER;
750 		goto again;
751 	}
752 
753 	if (allocdzn)
754 		zap_name_free(zn);
755 	return (B_FALSE);
756 }
757 
758 /*
759  * Routines for manipulating attributes.
760  */
761 
762 int
zap_lookup(objset_t * os,uint64_t zapobj,const char * name,uint64_t integer_size,uint64_t num_integers,void * buf)763 zap_lookup(objset_t *os, uint64_t zapobj, const char *name,
764     uint64_t integer_size, uint64_t num_integers, void *buf)
765 {
766 	return (zap_lookup_norm(os, zapobj, name, integer_size,
767 	    num_integers, buf, MT_EXACT, NULL, 0, NULL));
768 }
769 
770 int
zap_lookup_norm(objset_t * os,uint64_t zapobj,const char * name,uint64_t integer_size,uint64_t num_integers,void * buf,matchtype_t mt,char * realname,int rn_len,boolean_t * ncp)771 zap_lookup_norm(objset_t *os, uint64_t zapobj, const char *name,
772     uint64_t integer_size, uint64_t num_integers, void *buf,
773     matchtype_t mt, char *realname, int rn_len,
774     boolean_t *ncp)
775 {
776 	zap_t *zap;
777 	int err;
778 	mzap_ent_t *mze;
779 	zap_name_t *zn;
780 
781 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
782 	if (err)
783 		return (err);
784 	zn = zap_name_alloc(zap, name, mt);
785 	if (zn == NULL) {
786 		zap_unlockdir(zap);
787 		return (SET_ERROR(ENOTSUP));
788 	}
789 
790 	if (!zap->zap_ismicro) {
791 		err = fzap_lookup(zn, integer_size, num_integers, buf,
792 		    realname, rn_len, ncp);
793 	} else {
794 		mze = mze_find(zn);
795 		if (mze == NULL) {
796 			err = SET_ERROR(ENOENT);
797 		} else {
798 			if (num_integers < 1) {
799 				err = SET_ERROR(EOVERFLOW);
800 			} else if (integer_size != 8) {
801 				err = SET_ERROR(EINVAL);
802 			} else {
803 				*(uint64_t *)buf =
804 				    MZE_PHYS(zap, mze)->mze_value;
805 				(void) strlcpy(realname,
806 				    MZE_PHYS(zap, mze)->mze_name, rn_len);
807 				if (ncp) {
808 					*ncp = mzap_normalization_conflict(zap,
809 					    zn, mze);
810 				}
811 			}
812 		}
813 	}
814 	zap_name_free(zn);
815 	zap_unlockdir(zap);
816 	return (err);
817 }
818 
819 int
zap_prefetch_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints)820 zap_prefetch_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
821     int key_numints)
822 {
823 	zap_t *zap;
824 	int err;
825 	zap_name_t *zn;
826 
827 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
828 	if (err)
829 		return (err);
830 	zn = zap_name_alloc_uint64(zap, key, key_numints);
831 	if (zn == NULL) {
832 		zap_unlockdir(zap);
833 		return (SET_ERROR(ENOTSUP));
834 	}
835 
836 	fzap_prefetch(zn);
837 	zap_name_free(zn);
838 	zap_unlockdir(zap);
839 	return (err);
840 }
841 
842 int
zap_lookup_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints,uint64_t integer_size,uint64_t num_integers,void * buf)843 zap_lookup_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
844     int key_numints, uint64_t integer_size, uint64_t num_integers, void *buf)
845 {
846 	zap_t *zap;
847 	int err;
848 	zap_name_t *zn;
849 
850 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
851 	if (err)
852 		return (err);
853 	zn = zap_name_alloc_uint64(zap, key, key_numints);
854 	if (zn == NULL) {
855 		zap_unlockdir(zap);
856 		return (SET_ERROR(ENOTSUP));
857 	}
858 
859 	err = fzap_lookup(zn, integer_size, num_integers, buf,
860 	    NULL, 0, NULL);
861 	zap_name_free(zn);
862 	zap_unlockdir(zap);
863 	return (err);
864 }
865 
866 int
zap_contains(objset_t * os,uint64_t zapobj,const char * name)867 zap_contains(objset_t *os, uint64_t zapobj, const char *name)
868 {
869 	int err = zap_lookup_norm(os, zapobj, name, 0,
870 	    0, NULL, MT_EXACT, NULL, 0, NULL);
871 	if (err == EOVERFLOW || err == EINVAL)
872 		err = 0; /* found, but skipped reading the value */
873 	return (err);
874 }
875 
876 int
zap_length(objset_t * os,uint64_t zapobj,const char * name,uint64_t * integer_size,uint64_t * num_integers)877 zap_length(objset_t *os, uint64_t zapobj, const char *name,
878     uint64_t *integer_size, uint64_t *num_integers)
879 {
880 	zap_t *zap;
881 	int err;
882 	mzap_ent_t *mze;
883 	zap_name_t *zn;
884 
885 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
886 	if (err)
887 		return (err);
888 	zn = zap_name_alloc(zap, name, MT_EXACT);
889 	if (zn == NULL) {
890 		zap_unlockdir(zap);
891 		return (SET_ERROR(ENOTSUP));
892 	}
893 	if (!zap->zap_ismicro) {
894 		err = fzap_length(zn, integer_size, num_integers);
895 	} else {
896 		mze = mze_find(zn);
897 		if (mze == NULL) {
898 			err = SET_ERROR(ENOENT);
899 		} else {
900 			if (integer_size)
901 				*integer_size = 8;
902 			if (num_integers)
903 				*num_integers = 1;
904 		}
905 	}
906 	zap_name_free(zn);
907 	zap_unlockdir(zap);
908 	return (err);
909 }
910 
911 int
zap_length_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints,uint64_t * integer_size,uint64_t * num_integers)912 zap_length_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
913     int key_numints, uint64_t *integer_size, uint64_t *num_integers)
914 {
915 	zap_t *zap;
916 	int err;
917 	zap_name_t *zn;
918 
919 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
920 	if (err)
921 		return (err);
922 	zn = zap_name_alloc_uint64(zap, key, key_numints);
923 	if (zn == NULL) {
924 		zap_unlockdir(zap);
925 		return (SET_ERROR(ENOTSUP));
926 	}
927 	err = fzap_length(zn, integer_size, num_integers);
928 	zap_name_free(zn);
929 	zap_unlockdir(zap);
930 	return (err);
931 }
932 
933 static void
mzap_addent(zap_name_t * zn,uint64_t value)934 mzap_addent(zap_name_t *zn, uint64_t value)
935 {
936 	int i;
937 	zap_t *zap = zn->zn_zap;
938 	int start = zap->zap_m.zap_alloc_next;
939 	uint32_t cd;
940 
941 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
942 
943 #ifdef ZFS_DEBUG
944 	for (i = 0; i < zap->zap_m.zap_num_chunks; i++) {
945 		mzap_ent_phys_t *mze = &zap_m_phys(zap)->mz_chunk[i];
946 		ASSERT(strcmp(zn->zn_key_orig, mze->mze_name) != 0);
947 	}
948 #endif
949 
950 	cd = mze_find_unused_cd(zap, zn->zn_hash);
951 	/* given the limited size of the microzap, this can't happen */
952 	ASSERT(cd < zap_maxcd(zap));
953 
954 again:
955 	for (i = start; i < zap->zap_m.zap_num_chunks; i++) {
956 		mzap_ent_phys_t *mze = &zap_m_phys(zap)->mz_chunk[i];
957 		if (mze->mze_name[0] == 0) {
958 			mze->mze_value = value;
959 			mze->mze_cd = cd;
960 			(void) strcpy(mze->mze_name, zn->zn_key_orig);
961 			zap->zap_m.zap_num_entries++;
962 			zap->zap_m.zap_alloc_next = i+1;
963 			if (zap->zap_m.zap_alloc_next ==
964 			    zap->zap_m.zap_num_chunks)
965 				zap->zap_m.zap_alloc_next = 0;
966 			mze_insert(zap, i, zn->zn_hash);
967 			return;
968 		}
969 	}
970 	if (start != 0) {
971 		start = 0;
972 		goto again;
973 	}
974 	ASSERT(!"out of entries!");
975 }
976 
977 int
zap_add(objset_t * os,uint64_t zapobj,const char * key,int integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)978 zap_add(objset_t *os, uint64_t zapobj, const char *key,
979     int integer_size, uint64_t num_integers,
980     const void *val, dmu_tx_t *tx)
981 {
982 	zap_t *zap;
983 	int err;
984 	mzap_ent_t *mze;
985 	const uint64_t *intval = val;
986 	zap_name_t *zn;
987 
988 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, TRUE, &zap);
989 	if (err)
990 		return (err);
991 	zn = zap_name_alloc(zap, key, MT_EXACT);
992 	if (zn == NULL) {
993 		zap_unlockdir(zap);
994 		return (SET_ERROR(ENOTSUP));
995 	}
996 	if (!zap->zap_ismicro) {
997 		err = fzap_add(zn, integer_size, num_integers, val, tx);
998 		zap = zn->zn_zap;	/* fzap_add() may change zap */
999 	} else if (integer_size != 8 || num_integers != 1 ||
1000 	    strlen(key) >= MZAP_NAME_LEN) {
1001 		err = mzap_upgrade(&zn->zn_zap, tx, 0);
1002 		if (err == 0)
1003 			err = fzap_add(zn, integer_size, num_integers, val, tx);
1004 		zap = zn->zn_zap;	/* fzap_add() may change zap */
1005 	} else {
1006 		mze = mze_find(zn);
1007 		if (mze != NULL) {
1008 			err = SET_ERROR(EEXIST);
1009 		} else {
1010 			mzap_addent(zn, *intval);
1011 		}
1012 	}
1013 	ASSERT(zap == zn->zn_zap);
1014 	zap_name_free(zn);
1015 	if (zap != NULL)	/* may be NULL if fzap_add() failed */
1016 		zap_unlockdir(zap);
1017 	return (err);
1018 }
1019 
1020 int
zap_add_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints,int integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)1021 zap_add_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
1022     int key_numints, int integer_size, uint64_t num_integers,
1023     const void *val, dmu_tx_t *tx)
1024 {
1025 	zap_t *zap;
1026 	int err;
1027 	zap_name_t *zn;
1028 
1029 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, TRUE, &zap);
1030 	if (err)
1031 		return (err);
1032 	zn = zap_name_alloc_uint64(zap, key, key_numints);
1033 	if (zn == NULL) {
1034 		zap_unlockdir(zap);
1035 		return (SET_ERROR(ENOTSUP));
1036 	}
1037 	err = fzap_add(zn, integer_size, num_integers, val, tx);
1038 	zap = zn->zn_zap;	/* fzap_add() may change zap */
1039 	zap_name_free(zn);
1040 	if (zap != NULL)	/* may be NULL if fzap_add() failed */
1041 		zap_unlockdir(zap);
1042 	return (err);
1043 }
1044 
1045 int
zap_update(objset_t * os,uint64_t zapobj,const char * name,int integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)1046 zap_update(objset_t *os, uint64_t zapobj, const char *name,
1047     int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx)
1048 {
1049 	zap_t *zap;
1050 	mzap_ent_t *mze;
1051 	uint64_t oldval;
1052 	const uint64_t *intval = val;
1053 	zap_name_t *zn;
1054 	int err;
1055 
1056 #ifdef ZFS_DEBUG
1057 	/*
1058 	 * If there is an old value, it shouldn't change across the
1059 	 * lockdir (eg, due to bprewrite's xlation).
1060 	 */
1061 	if (integer_size == 8 && num_integers == 1)
1062 		(void) zap_lookup(os, zapobj, name, 8, 1, &oldval);
1063 #endif
1064 
1065 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, TRUE, &zap);
1066 	if (err)
1067 		return (err);
1068 	zn = zap_name_alloc(zap, name, MT_EXACT);
1069 	if (zn == NULL) {
1070 		zap_unlockdir(zap);
1071 		return (SET_ERROR(ENOTSUP));
1072 	}
1073 	if (!zap->zap_ismicro) {
1074 		err = fzap_update(zn, integer_size, num_integers, val, tx);
1075 		zap = zn->zn_zap;	/* fzap_update() may change zap */
1076 	} else if (integer_size != 8 || num_integers != 1 ||
1077 	    strlen(name) >= MZAP_NAME_LEN) {
1078 		dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n",
1079 		    zapobj, integer_size, num_integers, name);
1080 		err = mzap_upgrade(&zn->zn_zap, tx, 0);
1081 		if (err == 0)
1082 			err = fzap_update(zn, integer_size, num_integers,
1083 			    val, tx);
1084 		zap = zn->zn_zap;	/* fzap_update() may change zap */
1085 	} else {
1086 		mze = mze_find(zn);
1087 		if (mze != NULL) {
1088 			ASSERT3U(MZE_PHYS(zap, mze)->mze_value, ==, oldval);
1089 			MZE_PHYS(zap, mze)->mze_value = *intval;
1090 		} else {
1091 			mzap_addent(zn, *intval);
1092 		}
1093 	}
1094 	ASSERT(zap == zn->zn_zap);
1095 	zap_name_free(zn);
1096 	if (zap != NULL)	/* may be NULL if fzap_upgrade() failed */
1097 		zap_unlockdir(zap);
1098 	return (err);
1099 }
1100 
1101 int
zap_update_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints,int integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)1102 zap_update_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
1103     int key_numints,
1104     int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx)
1105 {
1106 	zap_t *zap;
1107 	zap_name_t *zn;
1108 	int err;
1109 
1110 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, TRUE, &zap);
1111 	if (err)
1112 		return (err);
1113 	zn = zap_name_alloc_uint64(zap, key, key_numints);
1114 	if (zn == NULL) {
1115 		zap_unlockdir(zap);
1116 		return (SET_ERROR(ENOTSUP));
1117 	}
1118 	err = fzap_update(zn, integer_size, num_integers, val, tx);
1119 	zap = zn->zn_zap;	/* fzap_update() may change zap */
1120 	zap_name_free(zn);
1121 	if (zap != NULL)	/* may be NULL if fzap_upgrade() failed */
1122 		zap_unlockdir(zap);
1123 	return (err);
1124 }
1125 
1126 int
zap_remove(objset_t * os,uint64_t zapobj,const char * name,dmu_tx_t * tx)1127 zap_remove(objset_t *os, uint64_t zapobj, const char *name, dmu_tx_t *tx)
1128 {
1129 	return (zap_remove_norm(os, zapobj, name, MT_EXACT, tx));
1130 }
1131 
1132 int
zap_remove_norm(objset_t * os,uint64_t zapobj,const char * name,matchtype_t mt,dmu_tx_t * tx)1133 zap_remove_norm(objset_t *os, uint64_t zapobj, const char *name,
1134     matchtype_t mt, dmu_tx_t *tx)
1135 {
1136 	zap_t *zap;
1137 	int err;
1138 	mzap_ent_t *mze;
1139 	zap_name_t *zn;
1140 
1141 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, FALSE, &zap);
1142 	if (err)
1143 		return (err);
1144 	zn = zap_name_alloc(zap, name, mt);
1145 	if (zn == NULL) {
1146 		zap_unlockdir(zap);
1147 		return (SET_ERROR(ENOTSUP));
1148 	}
1149 	if (!zap->zap_ismicro) {
1150 		err = fzap_remove(zn, tx);
1151 	} else {
1152 		mze = mze_find(zn);
1153 		if (mze == NULL) {
1154 			err = SET_ERROR(ENOENT);
1155 		} else {
1156 			zap->zap_m.zap_num_entries--;
1157 			bzero(&zap_m_phys(zap)->mz_chunk[mze->mze_chunkid],
1158 			    sizeof (mzap_ent_phys_t));
1159 			mze_remove(zap, mze);
1160 		}
1161 	}
1162 	zap_name_free(zn);
1163 	zap_unlockdir(zap);
1164 	return (err);
1165 }
1166 
1167 int
zap_remove_uint64(objset_t * os,uint64_t zapobj,const uint64_t * key,int key_numints,dmu_tx_t * tx)1168 zap_remove_uint64(objset_t *os, uint64_t zapobj, const uint64_t *key,
1169     int key_numints, dmu_tx_t *tx)
1170 {
1171 	zap_t *zap;
1172 	int err;
1173 	zap_name_t *zn;
1174 
1175 	err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, FALSE, &zap);
1176 	if (err)
1177 		return (err);
1178 	zn = zap_name_alloc_uint64(zap, key, key_numints);
1179 	if (zn == NULL) {
1180 		zap_unlockdir(zap);
1181 		return (SET_ERROR(ENOTSUP));
1182 	}
1183 	err = fzap_remove(zn, tx);
1184 	zap_name_free(zn);
1185 	zap_unlockdir(zap);
1186 	return (err);
1187 }
1188 
1189 /*
1190  * Routines for iterating over the attributes.
1191  */
1192 
1193 void
zap_cursor_init_serialized(zap_cursor_t * zc,objset_t * os,uint64_t zapobj,uint64_t serialized)1194 zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *os, uint64_t zapobj,
1195     uint64_t serialized)
1196 {
1197 	zc->zc_objset = os;
1198 	zc->zc_zap = NULL;
1199 	zc->zc_leaf = NULL;
1200 	zc->zc_zapobj = zapobj;
1201 	zc->zc_serialized = serialized;
1202 	zc->zc_hash = 0;
1203 	zc->zc_cd = 0;
1204 }
1205 
1206 void
zap_cursor_init(zap_cursor_t * zc,objset_t * os,uint64_t zapobj)1207 zap_cursor_init(zap_cursor_t *zc, objset_t *os, uint64_t zapobj)
1208 {
1209 	zap_cursor_init_serialized(zc, os, zapobj, 0);
1210 }
1211 
1212 void
zap_cursor_fini(zap_cursor_t * zc)1213 zap_cursor_fini(zap_cursor_t *zc)
1214 {
1215 	if (zc->zc_zap) {
1216 		rw_enter(&zc->zc_zap->zap_rwlock, RW_READER);
1217 		zap_unlockdir(zc->zc_zap);
1218 		zc->zc_zap = NULL;
1219 	}
1220 	if (zc->zc_leaf) {
1221 		rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
1222 		zap_put_leaf(zc->zc_leaf);
1223 		zc->zc_leaf = NULL;
1224 	}
1225 	zc->zc_objset = NULL;
1226 }
1227 
1228 uint64_t
zap_cursor_serialize(zap_cursor_t * zc)1229 zap_cursor_serialize(zap_cursor_t *zc)
1230 {
1231 	if (zc->zc_hash == -1ULL)
1232 		return (-1ULL);
1233 	if (zc->zc_zap == NULL)
1234 		return (zc->zc_serialized);
1235 	ASSERT((zc->zc_hash & zap_maxcd(zc->zc_zap)) == 0);
1236 	ASSERT(zc->zc_cd < zap_maxcd(zc->zc_zap));
1237 
1238 	/*
1239 	 * We want to keep the high 32 bits of the cursor zero if we can, so
1240 	 * that 32-bit programs can access this.  So usually use a small
1241 	 * (28-bit) hash value so we can fit 4 bits of cd into the low 32-bits
1242 	 * of the cursor.
1243 	 *
1244 	 * [ collision differentiator | zap_hashbits()-bit hash value ]
1245 	 */
1246 	return ((zc->zc_hash >> (64 - zap_hashbits(zc->zc_zap))) |
1247 	    ((uint64_t)zc->zc_cd << zap_hashbits(zc->zc_zap)));
1248 }
1249 
1250 int
zap_cursor_retrieve(zap_cursor_t * zc,zap_attribute_t * za)1251 zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za)
1252 {
1253 	int err;
1254 	avl_index_t idx;
1255 	mzap_ent_t mze_tofind;
1256 	mzap_ent_t *mze;
1257 
1258 	if (zc->zc_hash == -1ULL)
1259 		return (SET_ERROR(ENOENT));
1260 
1261 	if (zc->zc_zap == NULL) {
1262 		int hb;
1263 		err = zap_lockdir(zc->zc_objset, zc->zc_zapobj, NULL,
1264 		    RW_READER, TRUE, FALSE, &zc->zc_zap);
1265 		if (err)
1266 			return (err);
1267 
1268 		/*
1269 		 * To support zap_cursor_init_serialized, advance, retrieve,
1270 		 * we must add to the existing zc_cd, which may already
1271 		 * be 1 due to the zap_cursor_advance.
1272 		 */
1273 		ASSERT(zc->zc_hash == 0);
1274 		hb = zap_hashbits(zc->zc_zap);
1275 		zc->zc_hash = zc->zc_serialized << (64 - hb);
1276 		zc->zc_cd += zc->zc_serialized >> hb;
1277 		if (zc->zc_cd >= zap_maxcd(zc->zc_zap)) /* corrupt serialized */
1278 			zc->zc_cd = 0;
1279 	} else {
1280 		rw_enter(&zc->zc_zap->zap_rwlock, RW_READER);
1281 	}
1282 	if (!zc->zc_zap->zap_ismicro) {
1283 		err = fzap_cursor_retrieve(zc->zc_zap, zc, za);
1284 	} else {
1285 		mze_tofind.mze_hash = zc->zc_hash;
1286 		mze_tofind.mze_cd = zc->zc_cd;
1287 
1288 		mze = avl_find(&zc->zc_zap->zap_m.zap_avl, &mze_tofind, &idx);
1289 		if (mze == NULL) {
1290 			mze = avl_nearest(&zc->zc_zap->zap_m.zap_avl,
1291 			    idx, AVL_AFTER);
1292 		}
1293 		if (mze) {
1294 			mzap_ent_phys_t *mzep = MZE_PHYS(zc->zc_zap, mze);
1295 			ASSERT3U(mze->mze_cd, ==, mzep->mze_cd);
1296 			za->za_normalization_conflict =
1297 			    mzap_normalization_conflict(zc->zc_zap, NULL, mze);
1298 			za->za_integer_length = 8;
1299 			za->za_num_integers = 1;
1300 			za->za_first_integer = mzep->mze_value;
1301 			(void) strcpy(za->za_name, mzep->mze_name);
1302 			zc->zc_hash = mze->mze_hash;
1303 			zc->zc_cd = mze->mze_cd;
1304 			err = 0;
1305 		} else {
1306 			zc->zc_hash = -1ULL;
1307 			err = SET_ERROR(ENOENT);
1308 		}
1309 	}
1310 	rw_exit(&zc->zc_zap->zap_rwlock);
1311 	return (err);
1312 }
1313 
1314 void
zap_cursor_advance(zap_cursor_t * zc)1315 zap_cursor_advance(zap_cursor_t *zc)
1316 {
1317 	if (zc->zc_hash == -1ULL)
1318 		return;
1319 	zc->zc_cd++;
1320 }
1321 
1322 int
zap_get_stats(objset_t * os,uint64_t zapobj,zap_stats_t * zs)1323 zap_get_stats(objset_t *os, uint64_t zapobj, zap_stats_t *zs)
1324 {
1325 	int err;
1326 	zap_t *zap;
1327 
1328 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
1329 	if (err)
1330 		return (err);
1331 
1332 	bzero(zs, sizeof (zap_stats_t));
1333 
1334 	if (zap->zap_ismicro) {
1335 		zs->zs_blocksize = zap->zap_dbuf->db_size;
1336 		zs->zs_num_entries = zap->zap_m.zap_num_entries;
1337 		zs->zs_num_blocks = 1;
1338 	} else {
1339 		fzap_get_stats(zap, zs);
1340 	}
1341 	zap_unlockdir(zap);
1342 	return (0);
1343 }
1344 
1345 int
zap_count_write(objset_t * os,uint64_t zapobj,const char * name,int add,uint64_t * towrite,uint64_t * tooverwrite)1346 zap_count_write(objset_t *os, uint64_t zapobj, const char *name, int add,
1347     uint64_t *towrite, uint64_t *tooverwrite)
1348 {
1349 	zap_t *zap;
1350 	int err = 0;
1351 
1352 	/*
1353 	 * Since, we don't have a name, we cannot figure out which blocks will
1354 	 * be affected in this operation. So, account for the worst case :
1355 	 * - 3 blocks overwritten: target leaf, ptrtbl block, header block
1356 	 * - 4 new blocks written if adding:
1357 	 * 	- 2 blocks for possibly split leaves,
1358 	 * 	- 2 grown ptrtbl blocks
1359 	 *
1360 	 * This also accomodates the case where an add operation to a fairly
1361 	 * large microzap results in a promotion to fatzap.
1362 	 */
1363 	if (name == NULL) {
1364 		*towrite += (3 + (add ? 4 : 0)) * SPA_OLD_MAXBLOCKSIZE;
1365 		return (err);
1366 	}
1367 
1368 	/*
1369 	 * We lock the zap with adding == FALSE. Because, if we pass
1370 	 * the actual value of add, it could trigger a mzap_upgrade().
1371 	 * At present we are just evaluating the possibility of this operation
1372 	 * and hence we donot want to trigger an upgrade.
1373 	 */
1374 	err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, FALSE, &zap);
1375 	if (err)
1376 		return (err);
1377 
1378 	if (!zap->zap_ismicro) {
1379 		zap_name_t *zn = zap_name_alloc(zap, name, MT_EXACT);
1380 		if (zn) {
1381 			err = fzap_count_write(zn, add, towrite,
1382 			    tooverwrite);
1383 			zap_name_free(zn);
1384 		} else {
1385 			/*
1386 			 * We treat this case as similar to (name == NULL)
1387 			 */
1388 			*towrite += (3 + (add ? 4 : 0)) * SPA_OLD_MAXBLOCKSIZE;
1389 		}
1390 	} else {
1391 		/*
1392 		 * We are here if (name != NULL) and this is a micro-zap.
1393 		 * We account for the header block depending on whether it
1394 		 * is freeable.
1395 		 *
1396 		 * Incase of an add-operation it is hard to find out
1397 		 * if this add will promote this microzap to fatzap.
1398 		 * Hence, we consider the worst case and account for the
1399 		 * blocks assuming this microzap would be promoted to a
1400 		 * fatzap.
1401 		 *
1402 		 * 1 block overwritten  : header block
1403 		 * 4 new blocks written : 2 new split leaf, 2 grown
1404 		 *			ptrtbl blocks
1405 		 */
1406 		if (dmu_buf_freeable(zap->zap_dbuf))
1407 			*tooverwrite += MZAP_MAX_BLKSZ;
1408 		else
1409 			*towrite += MZAP_MAX_BLKSZ;
1410 
1411 		if (add) {
1412 			*towrite += 4 * MZAP_MAX_BLKSZ;
1413 		}
1414 	}
1415 
1416 	zap_unlockdir(zap);
1417 	return (err);
1418 }
1419