xref: /netbsd/external/cddl/osnet/dist/uts/common/fs/zfs/zap.c (revision 93f3d2b8)
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) 2012, 2016 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
25  */
26 
27 /*
28  * This file contains the top half of the zfs directory structure
29  * implementation. The bottom half is in zap_leaf.c.
30  *
31  * The zdir is an extendable hash data structure. There is a table of
32  * pointers to buckets (zap_t->zd_data->zd_leafs). The buckets are
33  * each a constant size and hold a variable number of directory entries.
34  * The buckets (aka "leaf nodes") are implemented in zap_leaf.c.
35  *
36  * The pointer table holds a power of 2 number of pointers.
37  * (1<<zap_t->zd_data->zd_phys->zd_prefix_len).  The bucket pointed to
38  * by the pointer at index i in the table holds entries whose hash value
39  * has a zd_prefix_len - bit prefix
40  */
41 
42 #include <sys/spa.h>
43 #include <sys/dmu.h>
44 #include <sys/zfs_context.h>
45 #include <sys/zfs_znode.h>
46 #include <sys/fs/zfs.h>
47 #include <sys/zap.h>
48 #include <sys/refcount.h>
49 #include <sys/zap_impl.h>
50 #include <sys/zap_leaf.h>
51 
52 int fzap_default_block_shift = 14; /* 16k blocksize */
53 
54 extern inline zap_phys_t *zap_f_phys(zap_t *zap);
55 
56 static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks);
57 
58 void
fzap_byteswap(void * vbuf,size_t size)59 fzap_byteswap(void *vbuf, size_t size)
60 {
61 	uint64_t block_type;
62 
63 	block_type = *(uint64_t *)vbuf;
64 
65 	if (block_type == ZBT_LEAF || block_type == BSWAP_64(ZBT_LEAF))
66 		zap_leaf_byteswap(vbuf, size);
67 	else {
68 		/* it's a ptrtbl block */
69 		byteswap_uint64_array(vbuf, size);
70 	}
71 }
72 
73 void
fzap_upgrade(zap_t * zap,dmu_tx_t * tx,zap_flags_t flags)74 fzap_upgrade(zap_t *zap, dmu_tx_t *tx, zap_flags_t flags)
75 {
76 	dmu_buf_t *db;
77 	zap_leaf_t *l;
78 	int i;
79 	zap_phys_t *zp;
80 
81 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
82 	zap->zap_ismicro = FALSE;
83 
84 	zap->zap_dbu.dbu_evict_func_sync = zap_evict_sync;
85 	zap->zap_dbu.dbu_evict_func_async = NULL;
86 
87 	mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0);
88 	zap->zap_f.zap_block_shift = highbit64(zap->zap_dbuf->db_size) - 1;
89 
90 	zp = zap_f_phys(zap);
91 	/*
92 	 * explicitly zero it since it might be coming from an
93 	 * initialized microzap
94 	 */
95 	bzero(zap->zap_dbuf->db_data, zap->zap_dbuf->db_size);
96 	zp->zap_block_type = ZBT_HEADER;
97 	zp->zap_magic = ZAP_MAGIC;
98 
99 	zp->zap_ptrtbl.zt_shift = ZAP_EMBEDDED_PTRTBL_SHIFT(zap);
100 
101 	zp->zap_freeblk = 2;		/* block 1 will be the first leaf */
102 	zp->zap_num_leafs = 1;
103 	zp->zap_num_entries = 0;
104 	zp->zap_salt = zap->zap_salt;
105 	zp->zap_normflags = zap->zap_normflags;
106 	zp->zap_flags = flags;
107 
108 	/* block 1 will be the first leaf */
109 	for (i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++)
110 		ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1;
111 
112 	/*
113 	 * set up block 1 - the first leaf
114 	 */
115 	VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
116 	    1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db, DMU_READ_NO_PREFETCH));
117 	dmu_buf_will_dirty(db, tx);
118 
119 	l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
120 	l->l_dbuf = db;
121 
122 	zap_leaf_init(l, zp->zap_normflags != 0);
123 
124 	kmem_free(l, sizeof (zap_leaf_t));
125 	dmu_buf_rele(db, FTAG);
126 }
127 
128 static int
zap_tryupgradedir(zap_t * zap,dmu_tx_t * tx)129 zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx)
130 {
131 	if (RW_WRITE_HELD(&zap->zap_rwlock))
132 		return (1);
133 	if (rw_tryupgrade(&zap->zap_rwlock)) {
134 		dmu_buf_will_dirty(zap->zap_dbuf, tx);
135 		return (1);
136 	}
137 	return (0);
138 }
139 
140 /*
141  * Generic routines for dealing with the pointer & cookie tables.
142  */
143 
144 static int
zap_table_grow(zap_t * zap,zap_table_phys_t * tbl,void (* transfer_func)(const uint64_t * src,uint64_t * dst,int n),dmu_tx_t * tx)145 zap_table_grow(zap_t *zap, zap_table_phys_t *tbl,
146     void (*transfer_func)(const uint64_t *src, uint64_t *dst, int n),
147     dmu_tx_t *tx)
148 {
149 	uint64_t b, newblk;
150 	dmu_buf_t *db_old, *db_new;
151 	int err;
152 	int bs = FZAP_BLOCK_SHIFT(zap);
153 	int hepb = 1<<(bs-4);
154 	/* hepb = half the number of entries in a block */
155 
156 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
157 	ASSERT(tbl->zt_blk != 0);
158 	ASSERT(tbl->zt_numblks > 0);
159 
160 	if (tbl->zt_nextblk != 0) {
161 		newblk = tbl->zt_nextblk;
162 	} else {
163 		newblk = zap_allocate_blocks(zap, tbl->zt_numblks * 2);
164 		tbl->zt_nextblk = newblk;
165 		ASSERT0(tbl->zt_blks_copied);
166 		dmu_prefetch(zap->zap_objset, zap->zap_object, 0,
167 		    tbl->zt_blk << bs, tbl->zt_numblks << bs,
168 		    ZIO_PRIORITY_SYNC_READ);
169 	}
170 
171 	/*
172 	 * Copy the ptrtbl from the old to new location.
173 	 */
174 
175 	b = tbl->zt_blks_copied;
176 	err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
177 	    (tbl->zt_blk + b) << bs, FTAG, &db_old, DMU_READ_NO_PREFETCH);
178 	if (err)
179 		return (err);
180 
181 	/* first half of entries in old[b] go to new[2*b+0] */
182 	VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
183 	    (newblk + 2*b+0) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH));
184 	dmu_buf_will_dirty(db_new, tx);
185 	transfer_func(db_old->db_data, db_new->db_data, hepb);
186 	dmu_buf_rele(db_new, FTAG);
187 
188 	/* second half of entries in old[b] go to new[2*b+1] */
189 	VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
190 	    (newblk + 2*b+1) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH));
191 	dmu_buf_will_dirty(db_new, tx);
192 	transfer_func((uint64_t *)db_old->db_data + hepb,
193 	    db_new->db_data, hepb);
194 	dmu_buf_rele(db_new, FTAG);
195 
196 	dmu_buf_rele(db_old, FTAG);
197 
198 	tbl->zt_blks_copied++;
199 
200 	dprintf("copied block %llu of %llu\n",
201 	    tbl->zt_blks_copied, tbl->zt_numblks);
202 
203 	if (tbl->zt_blks_copied == tbl->zt_numblks) {
204 		(void) dmu_free_range(zap->zap_objset, zap->zap_object,
205 		    tbl->zt_blk << bs, tbl->zt_numblks << bs, tx);
206 
207 		tbl->zt_blk = newblk;
208 		tbl->zt_numblks *= 2;
209 		tbl->zt_shift++;
210 		tbl->zt_nextblk = 0;
211 		tbl->zt_blks_copied = 0;
212 
213 		dprintf("finished; numblocks now %llu (%lluk entries)\n",
214 		    tbl->zt_numblks, 1<<(tbl->zt_shift-10));
215 	}
216 
217 	return (0);
218 }
219 
220 static int
zap_table_store(zap_t * zap,zap_table_phys_t * tbl,uint64_t idx,uint64_t val,dmu_tx_t * tx)221 zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val,
222     dmu_tx_t *tx)
223 {
224 	int err;
225 	uint64_t blk, off;
226 	int bs = FZAP_BLOCK_SHIFT(zap);
227 	dmu_buf_t *db;
228 
229 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
230 	ASSERT(tbl->zt_blk != 0);
231 
232 	dprintf("storing %llx at index %llx\n", val, idx);
233 
234 	blk = idx >> (bs-3);
235 	off = idx & ((1<<(bs-3))-1);
236 
237 	err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
238 	    (tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH);
239 	if (err)
240 		return (err);
241 	dmu_buf_will_dirty(db, tx);
242 
243 	if (tbl->zt_nextblk != 0) {
244 		uint64_t idx2 = idx * 2;
245 		uint64_t blk2 = idx2 >> (bs-3);
246 		uint64_t off2 = idx2 & ((1<<(bs-3))-1);
247 		dmu_buf_t *db2;
248 
249 		err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
250 		    (tbl->zt_nextblk + blk2) << bs, FTAG, &db2,
251 		    DMU_READ_NO_PREFETCH);
252 		if (err) {
253 			dmu_buf_rele(db, FTAG);
254 			return (err);
255 		}
256 		dmu_buf_will_dirty(db2, tx);
257 		((uint64_t *)db2->db_data)[off2] = val;
258 		((uint64_t *)db2->db_data)[off2+1] = val;
259 		dmu_buf_rele(db2, FTAG);
260 	}
261 
262 	((uint64_t *)db->db_data)[off] = val;
263 	dmu_buf_rele(db, FTAG);
264 
265 	return (0);
266 }
267 
268 static int
zap_table_load(zap_t * zap,zap_table_phys_t * tbl,uint64_t idx,uint64_t * valp)269 zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp)
270 {
271 	uint64_t blk, off;
272 	int err;
273 	dmu_buf_t *db;
274 	dnode_t *dn;
275 	int bs = FZAP_BLOCK_SHIFT(zap);
276 
277 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
278 
279 	blk = idx >> (bs-3);
280 	off = idx & ((1<<(bs-3))-1);
281 
282 	/*
283 	 * Note: this is equivalent to dmu_buf_hold(), but we use
284 	 * _dnode_enter / _by_dnode because it's faster because we don't
285 	 * have to hold the dnode.
286 	 */
287 	dn = dmu_buf_dnode_enter(zap->zap_dbuf);
288 	err = dmu_buf_hold_by_dnode(dn,
289 	    (tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH);
290 	dmu_buf_dnode_exit(zap->zap_dbuf);
291 	if (err)
292 		return (err);
293 	*valp = ((uint64_t *)db->db_data)[off];
294 	dmu_buf_rele(db, FTAG);
295 
296 	if (tbl->zt_nextblk != 0) {
297 		/*
298 		 * read the nextblk for the sake of i/o error checking,
299 		 * so that zap_table_load() will catch errors for
300 		 * zap_table_store.
301 		 */
302 		blk = (idx*2) >> (bs-3);
303 
304 		dn = dmu_buf_dnode_enter(zap->zap_dbuf);
305 		err = dmu_buf_hold_by_dnode(dn,
306 		    (tbl->zt_nextblk + blk) << bs, FTAG, &db,
307 		    DMU_READ_NO_PREFETCH);
308 		dmu_buf_dnode_exit(zap->zap_dbuf);
309 		if (err == 0)
310 			dmu_buf_rele(db, FTAG);
311 	}
312 	return (err);
313 }
314 
315 /*
316  * Routines for growing the ptrtbl.
317  */
318 
319 static void
zap_ptrtbl_transfer(const uint64_t * src,uint64_t * dst,int n)320 zap_ptrtbl_transfer(const uint64_t *src, uint64_t *dst, int n)
321 {
322 	int i;
323 	for (i = 0; i < n; i++) {
324 		uint64_t lb = src[i];
325 		dst[2*i+0] = lb;
326 		dst[2*i+1] = lb;
327 	}
328 }
329 
330 static int
zap_grow_ptrtbl(zap_t * zap,dmu_tx_t * tx)331 zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx)
332 {
333 	/*
334 	 * The pointer table should never use more hash bits than we
335 	 * have (otherwise we'd be using useless zero bits to index it).
336 	 * If we are within 2 bits of running out, stop growing, since
337 	 * this is already an aberrant condition.
338 	 */
339 	if (zap_f_phys(zap)->zap_ptrtbl.zt_shift >= zap_hashbits(zap) - 2)
340 		return (SET_ERROR(ENOSPC));
341 
342 	if (zap_f_phys(zap)->zap_ptrtbl.zt_numblks == 0) {
343 		/*
344 		 * We are outgrowing the "embedded" ptrtbl (the one
345 		 * stored in the header block).  Give it its own entire
346 		 * block, which will double the size of the ptrtbl.
347 		 */
348 		uint64_t newblk;
349 		dmu_buf_t *db_new;
350 		int err;
351 
352 		ASSERT3U(zap_f_phys(zap)->zap_ptrtbl.zt_shift, ==,
353 		    ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
354 		ASSERT0(zap_f_phys(zap)->zap_ptrtbl.zt_blk);
355 
356 		newblk = zap_allocate_blocks(zap, 1);
357 		err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
358 		    newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new,
359 		    DMU_READ_NO_PREFETCH);
360 		if (err)
361 			return (err);
362 		dmu_buf_will_dirty(db_new, tx);
363 		zap_ptrtbl_transfer(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
364 		    db_new->db_data, 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
365 		dmu_buf_rele(db_new, FTAG);
366 
367 		zap_f_phys(zap)->zap_ptrtbl.zt_blk = newblk;
368 		zap_f_phys(zap)->zap_ptrtbl.zt_numblks = 1;
369 		zap_f_phys(zap)->zap_ptrtbl.zt_shift++;
370 
371 		ASSERT3U(1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift, ==,
372 		    zap_f_phys(zap)->zap_ptrtbl.zt_numblks <<
373 		    (FZAP_BLOCK_SHIFT(zap)-3));
374 
375 		return (0);
376 	} else {
377 		return (zap_table_grow(zap, &zap_f_phys(zap)->zap_ptrtbl,
378 		    zap_ptrtbl_transfer, tx));
379 	}
380 }
381 
382 static void
zap_increment_num_entries(zap_t * zap,int delta,dmu_tx_t * tx)383 zap_increment_num_entries(zap_t *zap, int delta, dmu_tx_t *tx)
384 {
385 	dmu_buf_will_dirty(zap->zap_dbuf, tx);
386 	mutex_enter(&zap->zap_f.zap_num_entries_mtx);
387 	ASSERT(delta > 0 || zap_f_phys(zap)->zap_num_entries >= -delta);
388 	zap_f_phys(zap)->zap_num_entries += delta;
389 	mutex_exit(&zap->zap_f.zap_num_entries_mtx);
390 }
391 
392 static uint64_t
zap_allocate_blocks(zap_t * zap,int nblocks)393 zap_allocate_blocks(zap_t *zap, int nblocks)
394 {
395 	uint64_t newblk;
396 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
397 	newblk = zap_f_phys(zap)->zap_freeblk;
398 	zap_f_phys(zap)->zap_freeblk += nblocks;
399 	return (newblk);
400 }
401 
402 static void
zap_leaf_evict_sync(void * dbu)403 zap_leaf_evict_sync(void *dbu)
404 {
405 	zap_leaf_t *l = dbu;
406 
407 	rw_destroy(&l->l_rwlock);
408 	kmem_free(l, sizeof (zap_leaf_t));
409 }
410 
411 static zap_leaf_t *
zap_create_leaf(zap_t * zap,dmu_tx_t * tx)412 zap_create_leaf(zap_t *zap, dmu_tx_t *tx)
413 {
414 	void *winner;
415 	zap_leaf_t *l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
416 
417 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
418 
419 	rw_init(&l->l_rwlock, 0, 0, 0);
420 	rw_enter(&l->l_rwlock, RW_WRITER);
421 	l->l_blkid = zap_allocate_blocks(zap, 1);
422 	l->l_dbuf = NULL;
423 
424 	VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
425 	    l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf,
426 	    DMU_READ_NO_PREFETCH));
427 	dmu_buf_init_user(&l->l_dbu, zap_leaf_evict_sync, NULL, &l->l_dbuf);
428 	winner = dmu_buf_set_user(l->l_dbuf, &l->l_dbu);
429 	ASSERT(winner == NULL);
430 	dmu_buf_will_dirty(l->l_dbuf, tx);
431 
432 	zap_leaf_init(l, zap->zap_normflags != 0);
433 
434 	zap_f_phys(zap)->zap_num_leafs++;
435 
436 	return (l);
437 }
438 
439 int
fzap_count(zap_t * zap,uint64_t * count)440 fzap_count(zap_t *zap, uint64_t *count)
441 {
442 	ASSERT(!zap->zap_ismicro);
443 	mutex_enter(&zap->zap_f.zap_num_entries_mtx); /* unnecessary */
444 	*count = zap_f_phys(zap)->zap_num_entries;
445 	mutex_exit(&zap->zap_f.zap_num_entries_mtx);
446 	return (0);
447 }
448 
449 /*
450  * Routines for obtaining zap_leaf_t's
451  */
452 
453 void
zap_put_leaf(zap_leaf_t * l)454 zap_put_leaf(zap_leaf_t *l)
455 {
456 	rw_exit(&l->l_rwlock);
457 	dmu_buf_rele(l->l_dbuf, NULL);
458 }
459 
460 static zap_leaf_t *
zap_open_leaf(uint64_t blkid,dmu_buf_t * db)461 zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
462 {
463 	zap_leaf_t *l, *winner;
464 
465 	ASSERT(blkid != 0);
466 
467 	l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
468 	rw_init(&l->l_rwlock, 0, 0, 0);
469 	rw_enter(&l->l_rwlock, RW_WRITER);
470 	l->l_blkid = blkid;
471 	l->l_bs = highbit64(db->db_size) - 1;
472 	l->l_dbuf = db;
473 
474 	dmu_buf_init_user(&l->l_dbu, zap_leaf_evict_sync, NULL, &l->l_dbuf);
475 	winner = dmu_buf_set_user(db, &l->l_dbu);
476 
477 	rw_exit(&l->l_rwlock);
478 	if (winner != NULL) {
479 		/* someone else set it first */
480 		zap_leaf_evict_sync(&l->l_dbu);
481 		l = winner;
482 	}
483 
484 	/*
485 	 * lhr_pad was previously used for the next leaf in the leaf
486 	 * chain.  There should be no chained leafs (as we have removed
487 	 * support for them).
488 	 */
489 	ASSERT0(zap_leaf_phys(l)->l_hdr.lh_pad1);
490 
491 	/*
492 	 * There should be more hash entries than there can be
493 	 * chunks to put in the hash table
494 	 */
495 	ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3);
496 
497 	/* The chunks should begin at the end of the hash table */
498 	ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==,
499 	    &zap_leaf_phys(l)->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]);
500 
501 	/* The chunks should end at the end of the block */
502 	ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) -
503 	    (uintptr_t)zap_leaf_phys(l), ==, l->l_dbuf->db_size);
504 
505 	return (l);
506 }
507 
508 static int
zap_get_leaf_byblk(zap_t * zap,uint64_t blkid,dmu_tx_t * tx,krw_t lt,zap_leaf_t ** lp)509 zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt,
510     zap_leaf_t **lp)
511 {
512 	dmu_buf_t *db;
513 	zap_leaf_t *l;
514 	int bs = FZAP_BLOCK_SHIFT(zap);
515 	int err;
516 
517 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
518 
519 	dnode_t *dn = dmu_buf_dnode_enter(zap->zap_dbuf);
520 	err = dmu_buf_hold_by_dnode(dn,
521 	    blkid << bs, NULL, &db, DMU_READ_NO_PREFETCH);
522 	dmu_buf_dnode_exit(zap->zap_dbuf);
523 	if (err)
524 		return (err);
525 
526 	ASSERT3U(db->db_object, ==, zap->zap_object);
527 	ASSERT3U(db->db_offset, ==, blkid << bs);
528 	ASSERT3U(db->db_size, ==, 1 << bs);
529 	ASSERT(blkid != 0);
530 
531 	l = dmu_buf_get_user(db);
532 
533 	if (l == NULL)
534 		l = zap_open_leaf(blkid, db);
535 
536 	rw_enter(&l->l_rwlock, lt);
537 	/*
538 	 * Must lock before dirtying, otherwise zap_leaf_phys(l) could change,
539 	 * causing ASSERT below to fail.
540 	 */
541 	if (lt == RW_WRITER)
542 		dmu_buf_will_dirty(db, tx);
543 	ASSERT3U(l->l_blkid, ==, blkid);
544 	ASSERT3P(l->l_dbuf, ==, db);
545 	ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_block_type, ==, ZBT_LEAF);
546 	ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);
547 
548 	*lp = l;
549 	return (0);
550 }
551 
552 static int
zap_idx_to_blk(zap_t * zap,uint64_t idx,uint64_t * valp)553 zap_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t *valp)
554 {
555 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
556 
557 	if (zap_f_phys(zap)->zap_ptrtbl.zt_numblks == 0) {
558 		ASSERT3U(idx, <,
559 		    (1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift));
560 		*valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx);
561 		return (0);
562 	} else {
563 		return (zap_table_load(zap, &zap_f_phys(zap)->zap_ptrtbl,
564 		    idx, valp));
565 	}
566 }
567 
568 static int
zap_set_idx_to_blk(zap_t * zap,uint64_t idx,uint64_t blk,dmu_tx_t * tx)569 zap_set_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t blk, dmu_tx_t *tx)
570 {
571 	ASSERT(tx != NULL);
572 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
573 
574 	if (zap_f_phys(zap)->zap_ptrtbl.zt_blk == 0) {
575 		ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk;
576 		return (0);
577 	} else {
578 		return (zap_table_store(zap, &zap_f_phys(zap)->zap_ptrtbl,
579 		    idx, blk, tx));
580 	}
581 }
582 
583 static int
zap_deref_leaf(zap_t * zap,uint64_t h,dmu_tx_t * tx,krw_t lt,zap_leaf_t ** lp)584 zap_deref_leaf(zap_t *zap, uint64_t h, dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp)
585 {
586 	uint64_t idx, blk;
587 	int err;
588 
589 	ASSERT(zap->zap_dbuf == NULL ||
590 	    zap_f_phys(zap) == zap->zap_dbuf->db_data);
591 
592 	/* Reality check for corrupt zap objects (leaf or header). */
593 	if ((zap_f_phys(zap)->zap_block_type != ZBT_LEAF &&
594 	    zap_f_phys(zap)->zap_block_type != ZBT_HEADER) ||
595 	    zap_f_phys(zap)->zap_magic != ZAP_MAGIC) {
596 		return (SET_ERROR(EIO));
597 	}
598 
599 	idx = ZAP_HASH_IDX(h, zap_f_phys(zap)->zap_ptrtbl.zt_shift);
600 	err = zap_idx_to_blk(zap, idx, &blk);
601 	if (err != 0)
602 		return (err);
603 	err = zap_get_leaf_byblk(zap, blk, tx, lt, lp);
604 
605 	ASSERT(err ||
606 	    ZAP_HASH_IDX(h, zap_leaf_phys(*lp)->l_hdr.lh_prefix_len) ==
607 	    zap_leaf_phys(*lp)->l_hdr.lh_prefix);
608 	return (err);
609 }
610 
611 static int
zap_expand_leaf(zap_name_t * zn,zap_leaf_t * l,void * tag,dmu_tx_t * tx,zap_leaf_t ** lp)612 zap_expand_leaf(zap_name_t *zn, zap_leaf_t *l,
613     void *tag, dmu_tx_t *tx, zap_leaf_t **lp)
614 {
615 	zap_t *zap = zn->zn_zap;
616 	uint64_t hash = zn->zn_hash;
617 	zap_leaf_t *nl;
618 	int prefix_diff, i, err;
619 	uint64_t sibling;
620 	int old_prefix_len = zap_leaf_phys(l)->l_hdr.lh_prefix_len;
621 
622 	ASSERT3U(old_prefix_len, <=, zap_f_phys(zap)->zap_ptrtbl.zt_shift);
623 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
624 
625 	ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
626 	    zap_leaf_phys(l)->l_hdr.lh_prefix);
627 
628 	if (zap_tryupgradedir(zap, tx) == 0 ||
629 	    old_prefix_len == zap_f_phys(zap)->zap_ptrtbl.zt_shift) {
630 		/* We failed to upgrade, or need to grow the pointer table */
631 		objset_t *os = zap->zap_objset;
632 		uint64_t object = zap->zap_object;
633 
634 		zap_put_leaf(l);
635 		zap_unlockdir(zap, tag);
636 		err = zap_lockdir(os, object, tx, RW_WRITER,
637 		    FALSE, FALSE, tag, &zn->zn_zap);
638 		zap = zn->zn_zap;
639 		if (err)
640 			return (err);
641 		ASSERT(!zap->zap_ismicro);
642 
643 		while (old_prefix_len ==
644 		    zap_f_phys(zap)->zap_ptrtbl.zt_shift) {
645 			err = zap_grow_ptrtbl(zap, tx);
646 			if (err)
647 				return (err);
648 		}
649 
650 		err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
651 		if (err)
652 			return (err);
653 
654 		if (zap_leaf_phys(l)->l_hdr.lh_prefix_len != old_prefix_len) {
655 			/* it split while our locks were down */
656 			*lp = l;
657 			return (0);
658 		}
659 	}
660 	ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
661 	ASSERT3U(old_prefix_len, <, zap_f_phys(zap)->zap_ptrtbl.zt_shift);
662 	ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
663 	    zap_leaf_phys(l)->l_hdr.lh_prefix);
664 
665 	prefix_diff = zap_f_phys(zap)->zap_ptrtbl.zt_shift -
666 	    (old_prefix_len + 1);
667 	sibling = (ZAP_HASH_IDX(hash, old_prefix_len + 1) | 1) << prefix_diff;
668 
669 	/* check for i/o errors before doing zap_leaf_split */
670 	for (i = 0; i < (1ULL<<prefix_diff); i++) {
671 		uint64_t blk;
672 		err = zap_idx_to_blk(zap, sibling+i, &blk);
673 		if (err)
674 			return (err);
675 		ASSERT3U(blk, ==, l->l_blkid);
676 	}
677 
678 	nl = zap_create_leaf(zap, tx);
679 	zap_leaf_split(l, nl, zap->zap_normflags != 0);
680 
681 	/* set sibling pointers */
682 	for (i = 0; i < (1ULL << prefix_diff); i++) {
683 		err = zap_set_idx_to_blk(zap, sibling+i, nl->l_blkid, tx);
684 		ASSERT0(err); /* we checked for i/o errors above */
685 	}
686 
687 	if (hash & (1ULL << (64 - zap_leaf_phys(l)->l_hdr.lh_prefix_len))) {
688 		/* we want the sibling */
689 		zap_put_leaf(l);
690 		*lp = nl;
691 	} else {
692 		zap_put_leaf(nl);
693 		*lp = l;
694 	}
695 
696 	return (0);
697 }
698 
699 static void
zap_put_leaf_maybe_grow_ptrtbl(zap_name_t * zn,zap_leaf_t * l,void * tag,dmu_tx_t * tx)700 zap_put_leaf_maybe_grow_ptrtbl(zap_name_t *zn, zap_leaf_t *l,
701     void *tag, dmu_tx_t *tx)
702 {
703 	zap_t *zap = zn->zn_zap;
704 	int shift = zap_f_phys(zap)->zap_ptrtbl.zt_shift;
705 	int leaffull = (zap_leaf_phys(l)->l_hdr.lh_prefix_len == shift &&
706 	    zap_leaf_phys(l)->l_hdr.lh_nfree < ZAP_LEAF_LOW_WATER);
707 
708 	zap_put_leaf(l);
709 
710 	if (leaffull || zap_f_phys(zap)->zap_ptrtbl.zt_nextblk) {
711 		int err;
712 
713 		/*
714 		 * We are in the middle of growing the pointer table, or
715 		 * this leaf will soon make us grow it.
716 		 */
717 		if (zap_tryupgradedir(zap, tx) == 0) {
718 			objset_t *os = zap->zap_objset;
719 			uint64_t zapobj = zap->zap_object;
720 
721 			zap_unlockdir(zap, tag);
722 			err = zap_lockdir(os, zapobj, tx,
723 			    RW_WRITER, FALSE, FALSE, tag, &zn->zn_zap);
724 			zap = zn->zn_zap;
725 			if (err)
726 				return;
727 		}
728 
729 		/* could have finished growing while our locks were down */
730 		if (zap_f_phys(zap)->zap_ptrtbl.zt_shift == shift)
731 			(void) zap_grow_ptrtbl(zap, tx);
732 	}
733 }
734 
735 static int
fzap_checkname(zap_name_t * zn)736 fzap_checkname(zap_name_t *zn)
737 {
738 	if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN)
739 		return (SET_ERROR(ENAMETOOLONG));
740 	return (0);
741 }
742 
743 static int
fzap_checksize(uint64_t integer_size,uint64_t num_integers)744 fzap_checksize(uint64_t integer_size, uint64_t num_integers)
745 {
746 	/* Only integer sizes supported by C */
747 	switch (integer_size) {
748 	case 1:
749 	case 2:
750 	case 4:
751 	case 8:
752 		break;
753 	default:
754 		return (SET_ERROR(EINVAL));
755 	}
756 
757 	if (integer_size * num_integers > ZAP_MAXVALUELEN)
758 		return (E2BIG);
759 
760 	return (0);
761 }
762 
763 static int
fzap_check(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers)764 fzap_check(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers)
765 {
766 	int err;
767 
768 	if ((err = fzap_checkname(zn)) != 0)
769 		return (err);
770 	return (fzap_checksize(integer_size, num_integers));
771 }
772 
773 /*
774  * Routines for manipulating attributes.
775  */
776 int
fzap_lookup(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,void * buf,char * realname,int rn_len,boolean_t * ncp)777 fzap_lookup(zap_name_t *zn,
778     uint64_t integer_size, uint64_t num_integers, void *buf,
779     char *realname, int rn_len, boolean_t *ncp)
780 {
781 	zap_leaf_t *l;
782 	int err;
783 	zap_entry_handle_t zeh;
784 
785 	if ((err = fzap_checkname(zn)) != 0)
786 		return (err);
787 
788 	err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
789 	if (err != 0)
790 		return (err);
791 	err = zap_leaf_lookup(l, zn, &zeh);
792 	if (err == 0) {
793 		if ((err = fzap_checksize(integer_size, num_integers)) != 0) {
794 			zap_put_leaf(l);
795 			return (err);
796 		}
797 
798 		err = zap_entry_read(&zeh, integer_size, num_integers, buf);
799 		(void) zap_entry_read_name(zn->zn_zap, &zeh, rn_len, realname);
800 		if (ncp) {
801 			*ncp = zap_entry_normalization_conflict(&zeh,
802 			    zn, NULL, zn->zn_zap);
803 		}
804 	}
805 
806 	zap_put_leaf(l);
807 	return (err);
808 }
809 
810 int
fzap_add_cd(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,const void * val,uint32_t cd,void * tag,dmu_tx_t * tx)811 fzap_add_cd(zap_name_t *zn,
812     uint64_t integer_size, uint64_t num_integers,
813     const void *val, uint32_t cd, void *tag, dmu_tx_t *tx)
814 {
815 	zap_leaf_t *l;
816 	int err;
817 	zap_entry_handle_t zeh;
818 	zap_t *zap = zn->zn_zap;
819 
820 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
821 	ASSERT(!zap->zap_ismicro);
822 	ASSERT(fzap_check(zn, integer_size, num_integers) == 0);
823 
824 	err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
825 	if (err != 0)
826 		return (err);
827 retry:
828 	err = zap_leaf_lookup(l, zn, &zeh);
829 	if (err == 0) {
830 		err = SET_ERROR(EEXIST);
831 		goto out;
832 	}
833 	if (err != ENOENT)
834 		goto out;
835 
836 	err = zap_entry_create(l, zn, cd,
837 	    integer_size, num_integers, val, &zeh);
838 
839 	if (err == 0) {
840 		zap_increment_num_entries(zap, 1, tx);
841 	} else if (err == EAGAIN) {
842 		err = zap_expand_leaf(zn, l, tag, tx, &l);
843 		zap = zn->zn_zap;	/* zap_expand_leaf() may change zap */
844 		if (err == 0)
845 			goto retry;
846 	}
847 
848 out:
849 	if (zap != NULL)
850 		zap_put_leaf_maybe_grow_ptrtbl(zn, l, tag, tx);
851 	return (err);
852 }
853 
854 int
fzap_add(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,const void * val,void * tag,dmu_tx_t * tx)855 fzap_add(zap_name_t *zn,
856     uint64_t integer_size, uint64_t num_integers,
857     const void *val, void *tag, dmu_tx_t *tx)
858 {
859 	int err = fzap_check(zn, integer_size, num_integers);
860 	if (err != 0)
861 		return (err);
862 
863 	return (fzap_add_cd(zn, integer_size, num_integers,
864 	    val, ZAP_NEED_CD, tag, tx));
865 }
866 
867 int
fzap_update(zap_name_t * zn,int integer_size,uint64_t num_integers,const void * val,void * tag,dmu_tx_t * tx)868 fzap_update(zap_name_t *zn,
869     int integer_size, uint64_t num_integers, const void *val,
870     void *tag, dmu_tx_t *tx)
871 {
872 	zap_leaf_t *l;
873 	int err, create;
874 	zap_entry_handle_t zeh;
875 	zap_t *zap = zn->zn_zap;
876 
877 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
878 	err = fzap_check(zn, integer_size, num_integers);
879 	if (err != 0)
880 		return (err);
881 
882 	err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
883 	if (err != 0)
884 		return (err);
885 retry:
886 	err = zap_leaf_lookup(l, zn, &zeh);
887 	create = (err == ENOENT);
888 	ASSERT(err == 0 || err == ENOENT);
889 
890 	if (create) {
891 		err = zap_entry_create(l, zn, ZAP_NEED_CD,
892 		    integer_size, num_integers, val, &zeh);
893 		if (err == 0)
894 			zap_increment_num_entries(zap, 1, tx);
895 	} else {
896 		err = zap_entry_update(&zeh, integer_size, num_integers, val);
897 	}
898 
899 	if (err == EAGAIN) {
900 		err = zap_expand_leaf(zn, l, tag, tx, &l);
901 		zap = zn->zn_zap;	/* zap_expand_leaf() may change zap */
902 		if (err == 0)
903 			goto retry;
904 	}
905 
906 	if (zap != NULL)
907 		zap_put_leaf_maybe_grow_ptrtbl(zn, l, tag, tx);
908 	return (err);
909 }
910 
911 int
fzap_length(zap_name_t * zn,uint64_t * integer_size,uint64_t * num_integers)912 fzap_length(zap_name_t *zn,
913     uint64_t *integer_size, uint64_t *num_integers)
914 {
915 	zap_leaf_t *l;
916 	int err;
917 	zap_entry_handle_t zeh;
918 
919 	err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
920 	if (err != 0)
921 		return (err);
922 	err = zap_leaf_lookup(l, zn, &zeh);
923 	if (err != 0)
924 		goto out;
925 
926 	if (integer_size)
927 		*integer_size = zeh.zeh_integer_size;
928 	if (num_integers)
929 		*num_integers = zeh.zeh_num_integers;
930 out:
931 	zap_put_leaf(l);
932 	return (err);
933 }
934 
935 int
fzap_remove(zap_name_t * zn,dmu_tx_t * tx)936 fzap_remove(zap_name_t *zn, dmu_tx_t *tx)
937 {
938 	zap_leaf_t *l;
939 	int err;
940 	zap_entry_handle_t zeh;
941 
942 	err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, tx, RW_WRITER, &l);
943 	if (err != 0)
944 		return (err);
945 	err = zap_leaf_lookup(l, zn, &zeh);
946 	if (err == 0) {
947 		zap_entry_remove(&zeh);
948 		zap_increment_num_entries(zn->zn_zap, -1, tx);
949 	}
950 	zap_put_leaf(l);
951 	return (err);
952 }
953 
954 void
fzap_prefetch(zap_name_t * zn)955 fzap_prefetch(zap_name_t *zn)
956 {
957 	uint64_t idx, blk;
958 	zap_t *zap = zn->zn_zap;
959 	int bs;
960 
961 	idx = ZAP_HASH_IDX(zn->zn_hash,
962 	    zap_f_phys(zap)->zap_ptrtbl.zt_shift);
963 	if (zap_idx_to_blk(zap, idx, &blk) != 0)
964 		return;
965 	bs = FZAP_BLOCK_SHIFT(zap);
966 	dmu_prefetch(zap->zap_objset, zap->zap_object, 0, blk << bs, 1 << bs,
967 	    ZIO_PRIORITY_SYNC_READ);
968 }
969 
970 /*
971  * Helper functions for consumers.
972  */
973 
974 uint64_t
zap_create_link(objset_t * os,dmu_object_type_t ot,uint64_t parent_obj,const char * name,dmu_tx_t * tx)975 zap_create_link(objset_t *os, dmu_object_type_t ot, uint64_t parent_obj,
976     const char *name, dmu_tx_t *tx)
977 {
978 	uint64_t new_obj;
979 
980 	VERIFY((new_obj = zap_create(os, ot, DMU_OT_NONE, 0, tx)) > 0);
981 	VERIFY0(zap_add(os, parent_obj, name, sizeof (uint64_t), 1, &new_obj,
982 	    tx));
983 
984 	return (new_obj);
985 }
986 
987 int
zap_value_search(objset_t * os,uint64_t zapobj,uint64_t value,uint64_t mask,char * name)988 zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, uint64_t mask,
989     char *name)
990 {
991 	zap_cursor_t zc;
992 	zap_attribute_t *za;
993 	int err;
994 
995 	if (mask == 0)
996 		mask = -1ULL;
997 
998 	za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
999 	for (zap_cursor_init(&zc, os, zapobj);
1000 	    (err = zap_cursor_retrieve(&zc, za)) == 0;
1001 	    zap_cursor_advance(&zc)) {
1002 		if ((za->za_first_integer & mask) == (value & mask)) {
1003 			(void) strcpy(name, za->za_name);
1004 			break;
1005 		}
1006 	}
1007 	zap_cursor_fini(&zc);
1008 	kmem_free(za, sizeof (zap_attribute_t));
1009 	return (err);
1010 }
1011 
1012 int
zap_join(objset_t * os,uint64_t fromobj,uint64_t intoobj,dmu_tx_t * tx)1013 zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx)
1014 {
1015 	zap_cursor_t zc;
1016 	zap_attribute_t za;
1017 	int err;
1018 
1019 	err = 0;
1020 	for (zap_cursor_init(&zc, os, fromobj);
1021 	    zap_cursor_retrieve(&zc, &za) == 0;
1022 	    (void) zap_cursor_advance(&zc)) {
1023 		if (za.za_integer_length != 8 || za.za_num_integers != 1) {
1024 			err = SET_ERROR(EINVAL);
1025 			break;
1026 		}
1027 		err = zap_add(os, intoobj, za.za_name,
1028 		    8, 1, &za.za_first_integer, tx);
1029 		if (err)
1030 			break;
1031 	}
1032 	zap_cursor_fini(&zc);
1033 	return (err);
1034 }
1035 
1036 int
zap_join_key(objset_t * os,uint64_t fromobj,uint64_t intoobj,uint64_t value,dmu_tx_t * tx)1037 zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj,
1038     uint64_t value, dmu_tx_t *tx)
1039 {
1040 	zap_cursor_t zc;
1041 	zap_attribute_t za;
1042 	int err;
1043 
1044 	err = 0;
1045 	for (zap_cursor_init(&zc, os, fromobj);
1046 	    zap_cursor_retrieve(&zc, &za) == 0;
1047 	    (void) zap_cursor_advance(&zc)) {
1048 		if (za.za_integer_length != 8 || za.za_num_integers != 1) {
1049 			err = SET_ERROR(EINVAL);
1050 			break;
1051 		}
1052 		err = zap_add(os, intoobj, za.za_name,
1053 		    8, 1, &value, tx);
1054 		if (err)
1055 			break;
1056 	}
1057 	zap_cursor_fini(&zc);
1058 	return (err);
1059 }
1060 
1061 int
zap_join_increment(objset_t * os,uint64_t fromobj,uint64_t intoobj,dmu_tx_t * tx)1062 zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj,
1063     dmu_tx_t *tx)
1064 {
1065 	zap_cursor_t zc;
1066 	zap_attribute_t za;
1067 	int err;
1068 
1069 	err = 0;
1070 	for (zap_cursor_init(&zc, os, fromobj);
1071 	    zap_cursor_retrieve(&zc, &za) == 0;
1072 	    (void) zap_cursor_advance(&zc)) {
1073 		uint64_t delta = 0;
1074 
1075 		if (za.za_integer_length != 8 || za.za_num_integers != 1) {
1076 			err = SET_ERROR(EINVAL);
1077 			break;
1078 		}
1079 
1080 		err = zap_lookup(os, intoobj, za.za_name, 8, 1, &delta);
1081 		if (err != 0 && err != ENOENT)
1082 			break;
1083 		delta += za.za_first_integer;
1084 		err = zap_update(os, intoobj, za.za_name, 8, 1, &delta, tx);
1085 		if (err)
1086 			break;
1087 	}
1088 	zap_cursor_fini(&zc);
1089 	return (err);
1090 }
1091 
1092 int
zap_add_int(objset_t * os,uint64_t obj,uint64_t value,dmu_tx_t * tx)1093 zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
1094 {
1095 	char name[20];
1096 
1097 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
1098 	return (zap_add(os, obj, name, 8, 1, &value, tx));
1099 }
1100 
1101 int
zap_remove_int(objset_t * os,uint64_t obj,uint64_t value,dmu_tx_t * tx)1102 zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
1103 {
1104 	char name[20];
1105 
1106 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
1107 	return (zap_remove(os, obj, name, tx));
1108 }
1109 
1110 int
zap_lookup_int(objset_t * os,uint64_t obj,uint64_t value)1111 zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value)
1112 {
1113 	char name[20];
1114 
1115 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
1116 	return (zap_lookup(os, obj, name, 8, 1, &value));
1117 }
1118 
1119 int
zap_add_int_key(objset_t * os,uint64_t obj,uint64_t key,uint64_t value,dmu_tx_t * tx)1120 zap_add_int_key(objset_t *os, uint64_t obj,
1121     uint64_t key, uint64_t value, dmu_tx_t *tx)
1122 {
1123 	char name[20];
1124 
1125 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
1126 	return (zap_add(os, obj, name, 8, 1, &value, tx));
1127 }
1128 
1129 int
zap_update_int_key(objset_t * os,uint64_t obj,uint64_t key,uint64_t value,dmu_tx_t * tx)1130 zap_update_int_key(objset_t *os, uint64_t obj,
1131     uint64_t key, uint64_t value, dmu_tx_t *tx)
1132 {
1133 	char name[20];
1134 
1135 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
1136 	return (zap_update(os, obj, name, 8, 1, &value, tx));
1137 }
1138 
1139 int
zap_lookup_int_key(objset_t * os,uint64_t obj,uint64_t key,uint64_t * valuep)1140 zap_lookup_int_key(objset_t *os, uint64_t obj, uint64_t key, uint64_t *valuep)
1141 {
1142 	char name[20];
1143 
1144 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
1145 	return (zap_lookup(os, obj, name, 8, 1, valuep));
1146 }
1147 
1148 int
zap_increment(objset_t * os,uint64_t obj,const char * name,int64_t delta,dmu_tx_t * tx)1149 zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta,
1150     dmu_tx_t *tx)
1151 {
1152 	uint64_t value = 0;
1153 	int err;
1154 
1155 	if (delta == 0)
1156 		return (0);
1157 
1158 	err = zap_lookup(os, obj, name, 8, 1, &value);
1159 	if (err != 0 && err != ENOENT)
1160 		return (err);
1161 	value += delta;
1162 	if (value == 0)
1163 		err = zap_remove(os, obj, name, tx);
1164 	else
1165 		err = zap_update(os, obj, name, 8, 1, &value, tx);
1166 	return (err);
1167 }
1168 
1169 int
zap_increment_int(objset_t * os,uint64_t obj,uint64_t key,int64_t delta,dmu_tx_t * tx)1170 zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta,
1171     dmu_tx_t *tx)
1172 {
1173 	char name[20];
1174 
1175 	(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
1176 	return (zap_increment(os, obj, name, delta, tx));
1177 }
1178 
1179 /*
1180  * Routines for iterating over the attributes.
1181  */
1182 
1183 int
fzap_cursor_retrieve(zap_t * zap,zap_cursor_t * zc,zap_attribute_t * za)1184 fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za)
1185 {
1186 	int err = ENOENT;
1187 	zap_entry_handle_t zeh;
1188 	zap_leaf_t *l;
1189 
1190 	/* retrieve the next entry at or after zc_hash/zc_cd */
1191 	/* if no entry, return ENOENT */
1192 
1193 	if (zc->zc_leaf &&
1194 	    (ZAP_HASH_IDX(zc->zc_hash,
1195 	    zap_leaf_phys(zc->zc_leaf)->l_hdr.lh_prefix_len) !=
1196 	    zap_leaf_phys(zc->zc_leaf)->l_hdr.lh_prefix)) {
1197 		rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
1198 		zap_put_leaf(zc->zc_leaf);
1199 		zc->zc_leaf = NULL;
1200 	}
1201 
1202 again:
1203 	if (zc->zc_leaf == NULL) {
1204 		err = zap_deref_leaf(zap, zc->zc_hash, NULL, RW_READER,
1205 		    &zc->zc_leaf);
1206 		if (err != 0)
1207 			return (err);
1208 	} else {
1209 		rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
1210 	}
1211 	l = zc->zc_leaf;
1212 
1213 	err = zap_leaf_lookup_closest(l, zc->zc_hash, zc->zc_cd, &zeh);
1214 
1215 	if (err == ENOENT) {
1216 		uint64_t nocare =
1217 		    (1ULL << (64 - zap_leaf_phys(l)->l_hdr.lh_prefix_len)) - 1;
1218 		zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1;
1219 		zc->zc_cd = 0;
1220 		if (zap_leaf_phys(l)->l_hdr.lh_prefix_len == 0 ||
1221 		    zc->zc_hash == 0) {
1222 			zc->zc_hash = -1ULL;
1223 		} else {
1224 			zap_put_leaf(zc->zc_leaf);
1225 			zc->zc_leaf = NULL;
1226 			goto again;
1227 		}
1228 	}
1229 
1230 	if (err == 0) {
1231 		zc->zc_hash = zeh.zeh_hash;
1232 		zc->zc_cd = zeh.zeh_cd;
1233 		za->za_integer_length = zeh.zeh_integer_size;
1234 		za->za_num_integers = zeh.zeh_num_integers;
1235 		if (zeh.zeh_num_integers == 0) {
1236 			za->za_first_integer = 0;
1237 		} else {
1238 			err = zap_entry_read(&zeh, 8, 1, &za->za_first_integer);
1239 			ASSERT(err == 0 || err == EOVERFLOW);
1240 		}
1241 		err = zap_entry_read_name(zap, &zeh,
1242 		    sizeof (za->za_name), za->za_name);
1243 		ASSERT(err == 0);
1244 
1245 		za->za_normalization_conflict =
1246 		    zap_entry_normalization_conflict(&zeh,
1247 		    NULL, za->za_name, zap);
1248 	}
1249 	rw_exit(&zc->zc_leaf->l_rwlock);
1250 	return (err);
1251 }
1252 
1253 static void
zap_stats_ptrtbl(zap_t * zap,uint64_t * tbl,int len,zap_stats_t * zs)1254 zap_stats_ptrtbl(zap_t *zap, uint64_t *tbl, int len, zap_stats_t *zs)
1255 {
1256 	int i, err;
1257 	uint64_t lastblk = 0;
1258 
1259 	/*
1260 	 * NB: if a leaf has more pointers than an entire ptrtbl block
1261 	 * can hold, then it'll be accounted for more than once, since
1262 	 * we won't have lastblk.
1263 	 */
1264 	for (i = 0; i < len; i++) {
1265 		zap_leaf_t *l;
1266 
1267 		if (tbl[i] == lastblk)
1268 			continue;
1269 		lastblk = tbl[i];
1270 
1271 		err = zap_get_leaf_byblk(zap, tbl[i], NULL, RW_READER, &l);
1272 		if (err == 0) {
1273 			zap_leaf_stats(zap, l, zs);
1274 			zap_put_leaf(l);
1275 		}
1276 	}
1277 }
1278 
1279 int
fzap_cursor_move_to_key(zap_cursor_t * zc,zap_name_t * zn)1280 fzap_cursor_move_to_key(zap_cursor_t *zc, zap_name_t *zn)
1281 {
1282 	int err;
1283 	zap_leaf_t *l;
1284 	zap_entry_handle_t zeh;
1285 
1286 	if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN)
1287 		return (SET_ERROR(ENAMETOOLONG));
1288 
1289 	err = zap_deref_leaf(zc->zc_zap, zn->zn_hash, NULL, RW_READER, &l);
1290 	if (err != 0)
1291 		return (err);
1292 
1293 	err = zap_leaf_lookup(l, zn, &zeh);
1294 	if (err != 0)
1295 		return (err);
1296 
1297 	zc->zc_leaf = l;
1298 	zc->zc_hash = zeh.zeh_hash;
1299 	zc->zc_cd = zeh.zeh_cd;
1300 
1301 	return (err);
1302 }
1303 
1304 void
fzap_get_stats(zap_t * zap,zap_stats_t * zs)1305 fzap_get_stats(zap_t *zap, zap_stats_t *zs)
1306 {
1307 	int bs = FZAP_BLOCK_SHIFT(zap);
1308 	zs->zs_blocksize = 1ULL << bs;
1309 
1310 	/*
1311 	 * Set zap_phys_t fields
1312 	 */
1313 	zs->zs_num_leafs = zap_f_phys(zap)->zap_num_leafs;
1314 	zs->zs_num_entries = zap_f_phys(zap)->zap_num_entries;
1315 	zs->zs_num_blocks = zap_f_phys(zap)->zap_freeblk;
1316 	zs->zs_block_type = zap_f_phys(zap)->zap_block_type;
1317 	zs->zs_magic = zap_f_phys(zap)->zap_magic;
1318 	zs->zs_salt = zap_f_phys(zap)->zap_salt;
1319 
1320 	/*
1321 	 * Set zap_ptrtbl fields
1322 	 */
1323 	zs->zs_ptrtbl_len = 1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift;
1324 	zs->zs_ptrtbl_nextblk = zap_f_phys(zap)->zap_ptrtbl.zt_nextblk;
1325 	zs->zs_ptrtbl_blks_copied =
1326 	    zap_f_phys(zap)->zap_ptrtbl.zt_blks_copied;
1327 	zs->zs_ptrtbl_zt_blk = zap_f_phys(zap)->zap_ptrtbl.zt_blk;
1328 	zs->zs_ptrtbl_zt_numblks = zap_f_phys(zap)->zap_ptrtbl.zt_numblks;
1329 	zs->zs_ptrtbl_zt_shift = zap_f_phys(zap)->zap_ptrtbl.zt_shift;
1330 
1331 	if (zap_f_phys(zap)->zap_ptrtbl.zt_numblks == 0) {
1332 		/* the ptrtbl is entirely in the header block. */
1333 		zap_stats_ptrtbl(zap, &ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
1334 		    1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap), zs);
1335 	} else {
1336 		int b;
1337 
1338 		dmu_prefetch(zap->zap_objset, zap->zap_object, 0,
1339 		    zap_f_phys(zap)->zap_ptrtbl.zt_blk << bs,
1340 		    zap_f_phys(zap)->zap_ptrtbl.zt_numblks << bs,
1341 		    ZIO_PRIORITY_SYNC_READ);
1342 
1343 		for (b = 0; b < zap_f_phys(zap)->zap_ptrtbl.zt_numblks;
1344 		    b++) {
1345 			dmu_buf_t *db;
1346 			int err;
1347 
1348 			err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
1349 			    (zap_f_phys(zap)->zap_ptrtbl.zt_blk + b) << bs,
1350 			    FTAG, &db, DMU_READ_NO_PREFETCH);
1351 			if (err == 0) {
1352 				zap_stats_ptrtbl(zap, db->db_data,
1353 				    1<<(bs-3), zs);
1354 				dmu_buf_rele(db, FTAG);
1355 			}
1356 		}
1357 	}
1358 }
1359 
1360 int
fzap_count_write(zap_name_t * zn,int add,refcount_t * towrite,refcount_t * tooverwrite)1361 fzap_count_write(zap_name_t *zn, int add, refcount_t *towrite,
1362     refcount_t *tooverwrite)
1363 {
1364 	zap_t *zap = zn->zn_zap;
1365 	zap_leaf_t *l;
1366 	int err;
1367 
1368 	/*
1369 	 * Account for the header block of the fatzap.
1370 	 */
1371 	if (!add && dmu_buf_freeable(zap->zap_dbuf)) {
1372 		(void) refcount_add_many(tooverwrite,
1373 		    zap->zap_dbuf->db_size, FTAG);
1374 	} else {
1375 		(void) refcount_add_many(towrite,
1376 		    zap->zap_dbuf->db_size, FTAG);
1377 	}
1378 
1379 	/*
1380 	 * Account for the pointer table blocks.
1381 	 * If we are adding we need to account for the following cases :
1382 	 * - If the pointer table is embedded, this operation could force an
1383 	 *   external pointer table.
1384 	 * - If this already has an external pointer table this operation
1385 	 *   could extend the table.
1386 	 */
1387 	if (add) {
1388 		if (zap_f_phys(zap)->zap_ptrtbl.zt_blk == 0) {
1389 			(void) refcount_add_many(towrite,
1390 			    zap->zap_dbuf->db_size, FTAG);
1391 		} else {
1392 			(void) refcount_add_many(towrite,
1393 			    zap->zap_dbuf->db_size * 3, FTAG);
1394 		}
1395 	}
1396 
1397 	/*
1398 	 * Now, check if the block containing leaf is freeable
1399 	 * and account accordingly.
1400 	 */
1401 	err = zap_deref_leaf(zap, zn->zn_hash, NULL, RW_READER, &l);
1402 	if (err != 0) {
1403 		return (err);
1404 	}
1405 
1406 	if (!add && dmu_buf_freeable(l->l_dbuf)) {
1407 		(void) refcount_add_many(tooverwrite, l->l_dbuf->db_size, FTAG);
1408 	} else {
1409 		/*
1410 		 * If this an add operation, the leaf block could split.
1411 		 * Hence, we need to account for an additional leaf block.
1412 		 */
1413 		(void) refcount_add_many(towrite,
1414 		    (add ? 2 : 1) * l->l_dbuf->db_size, FTAG);
1415 	}
1416 
1417 	zap_put_leaf(l);
1418 	return (0);
1419 }
1420