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