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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 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/dmu.h>
27 #include <sys/dmu_impl.h>
28 #include <sys/dmu_tx.h>
29 #include <sys/dbuf.h>
30 #include <sys/dnode.h>
31 #include <sys/zfs_context.h>
32 #include <sys/dmu_objset.h>
33 #include <sys/dmu_traverse.h>
34 #include <sys/dsl_dataset.h>
35 #include <sys/dsl_dir.h>
36 #include <sys/dsl_pool.h>
37 #include <sys/dsl_synctask.h>
38 #include <sys/dsl_prop.h>
39 #include <sys/dmu_zfetch.h>
40 #include <sys/zfs_ioctl.h>
41 #include <sys/zap.h>
42 #include <sys/zio_checksum.h>
43 #ifdef _KERNEL
44 #include <sys/vmsystm.h>
45 #include <sys/zfs_znode.h>
46 #endif
47
48 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
49 { byteswap_uint8_array, TRUE, "unallocated" },
50 { zap_byteswap, TRUE, "object directory" },
51 { byteswap_uint64_array, TRUE, "object array" },
52 { byteswap_uint8_array, TRUE, "packed nvlist" },
53 { byteswap_uint64_array, TRUE, "packed nvlist size" },
54 { byteswap_uint64_array, TRUE, "bplist" },
55 { byteswap_uint64_array, TRUE, "bplist header" },
56 { byteswap_uint64_array, TRUE, "SPA space map header" },
57 { byteswap_uint64_array, TRUE, "SPA space map" },
58 { byteswap_uint64_array, TRUE, "ZIL intent log" },
59 { dnode_buf_byteswap, TRUE, "DMU dnode" },
60 { dmu_objset_byteswap, TRUE, "DMU objset" },
61 { byteswap_uint64_array, TRUE, "DSL directory" },
62 { zap_byteswap, TRUE, "DSL directory child map"},
63 { zap_byteswap, TRUE, "DSL dataset snap map" },
64 { zap_byteswap, TRUE, "DSL props" },
65 { byteswap_uint64_array, TRUE, "DSL dataset" },
66 { zfs_znode_byteswap, TRUE, "ZFS znode" },
67 { zfs_oldacl_byteswap, TRUE, "ZFS V0 ACL" },
68 { byteswap_uint8_array, FALSE, "ZFS plain file" },
69 { zap_byteswap, TRUE, "ZFS directory" },
70 { zap_byteswap, TRUE, "ZFS master node" },
71 { zap_byteswap, TRUE, "ZFS delete queue" },
72 { byteswap_uint8_array, FALSE, "zvol object" },
73 { zap_byteswap, TRUE, "zvol prop" },
74 { byteswap_uint8_array, FALSE, "other uint8[]" },
75 { byteswap_uint64_array, FALSE, "other uint64[]" },
76 { zap_byteswap, TRUE, "other ZAP" },
77 { zap_byteswap, TRUE, "persistent error log" },
78 { byteswap_uint8_array, TRUE, "SPA history" },
79 { byteswap_uint64_array, TRUE, "SPA history offsets" },
80 { zap_byteswap, TRUE, "Pool properties" },
81 { zap_byteswap, TRUE, "DSL permissions" },
82 { zfs_acl_byteswap, TRUE, "ZFS ACL" },
83 { byteswap_uint8_array, TRUE, "ZFS SYSACL" },
84 { byteswap_uint8_array, TRUE, "FUID table" },
85 { byteswap_uint64_array, TRUE, "FUID table size" },
86 { zap_byteswap, TRUE, "DSL dataset next clones"},
87 { zap_byteswap, TRUE, "scrub work queue" },
88 { zap_byteswap, TRUE, "ZFS user/group used" },
89 { zap_byteswap, TRUE, "ZFS user/group quota" },
90 };
91
92 int
93 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
94 void *tag, dmu_buf_t **dbp)
95 {
96 dnode_t *dn;
97 uint64_t blkid;
98 dmu_buf_impl_t *db;
99 int err;
100
101 err = dnode_hold(os->os, object, FTAG, &dn);
102 if (err)
103 return (err);
104 blkid = dbuf_whichblock(dn, offset);
105 rw_enter(&dn->dn_struct_rwlock, RW_READER);
106 db = dbuf_hold(dn, blkid, tag);
107 rw_exit(&dn->dn_struct_rwlock);
108 if (db == NULL) {
109 err = EIO;
110 } else {
111 err = dbuf_read(db, NULL, DB_RF_CANFAIL);
112 if (err) {
113 dbuf_rele(db, tag);
114 db = NULL;
115 }
116 }
117
118 dnode_rele(dn, FTAG);
119 *dbp = &db->db;
120 return (err);
121 }
122
123 int
124 dmu_bonus_max(void)
125 {
126 return (DN_MAX_BONUSLEN);
127 }
128
129 int
130 dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx)
131 {
132 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
133
134 if (dn->dn_bonus != (dmu_buf_impl_t *)db)
135 return (EINVAL);
136 if (newsize < 0 || newsize > db->db_size)
137 return (EINVAL);
138 dnode_setbonuslen(dn, newsize, tx);
139 return (0);
140 }
141
142 /*
143 * returns ENOENT, EIO, or 0.
144 */
145 int
146 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
147 {
148 dnode_t *dn;
149 dmu_buf_impl_t *db;
150 int error;
151
152 error = dnode_hold(os->os, object, FTAG, &dn);
153 if (error)
154 return (error);
155
156 rw_enter(&dn->dn_struct_rwlock, RW_READER);
157 if (dn->dn_bonus == NULL) {
158 rw_exit(&dn->dn_struct_rwlock);
159 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
160 if (dn->dn_bonus == NULL)
161 dbuf_create_bonus(dn);
162 }
163 db = dn->dn_bonus;
164 rw_exit(&dn->dn_struct_rwlock);
165
166 /* as long as the bonus buf is held, the dnode will be held */
167 if (refcount_add(&db->db_holds, tag) == 1)
168 VERIFY(dnode_add_ref(dn, db));
169
170 dnode_rele(dn, FTAG);
171
172 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED));
173
174 *dbp = &db->db;
175 return (0);
176 }
177
178 /*
179 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
180 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
181 * and can induce severe lock contention when writing to several files
182 * whose dnodes are in the same block.
183 */
184 static int
185 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
186 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
187 {
188 dsl_pool_t *dp = NULL;
189 dmu_buf_t **dbp;
190 uint64_t blkid, nblks, i;
191 uint32_t dbuf_flags;
192 int err;
193 zio_t *zio;
194 hrtime_t start;
195
196 ASSERT(length <= DMU_MAX_ACCESS);
197
198 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT;
199 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
200 dbuf_flags |= DB_RF_NOPREFETCH;
201
202 rw_enter(&dn->dn_struct_rwlock, RW_READER);
203 if (dn->dn_datablkshift) {
204 int blkshift = dn->dn_datablkshift;
205 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
206 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
207 } else {
208 if (offset + length > dn->dn_datablksz) {
209 zfs_panic_recover("zfs: accessing past end of object "
210 "%llx/%llx (size=%u access=%llu+%llu)",
211 (longlong_t)dn->dn_objset->
212 os_dsl_dataset->ds_object,
213 (longlong_t)dn->dn_object, dn->dn_datablksz,
214 (longlong_t)offset, (longlong_t)length);
215 return (EIO);
216 }
217 nblks = 1;
218 }
219 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
220
221 if (dn->dn_objset->os_dsl_dataset)
222 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
223 if (dp && dsl_pool_sync_context(dp))
224 start = gethrtime();
225 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
226 blkid = dbuf_whichblock(dn, offset);
227 for (i = 0; i < nblks; i++) {
228 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
229 if (db == NULL) {
230 rw_exit(&dn->dn_struct_rwlock);
231 dmu_buf_rele_array(dbp, nblks, tag);
232 zio_nowait(zio);
233 return (EIO);
234 }
235 /* initiate async i/o */
236 if (read) {
237 rw_exit(&dn->dn_struct_rwlock);
238 (void) dbuf_read(db, zio, dbuf_flags);
239 rw_enter(&dn->dn_struct_rwlock, RW_READER);
240 }
241 dbp[i] = &db->db;
242 }
243 rw_exit(&dn->dn_struct_rwlock);
244
245 /* wait for async i/o */
246 err = zio_wait(zio);
247 /* track read overhead when we are in sync context */
248 if (dp && dsl_pool_sync_context(dp))
249 dp->dp_read_overhead += gethrtime() - start;
250 if (err) {
251 dmu_buf_rele_array(dbp, nblks, tag);
252 return (err);
253 }
254
255 /* wait for other io to complete */
256 if (read) {
257 for (i = 0; i < nblks; i++) {
258 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
259 mutex_enter(&db->db_mtx);
260 while (db->db_state == DB_READ ||
261 db->db_state == DB_FILL)
262 cv_wait(&db->db_changed, &db->db_mtx);
263 if (db->db_state == DB_UNCACHED)
264 err = EIO;
265 mutex_exit(&db->db_mtx);
266 if (err) {
267 dmu_buf_rele_array(dbp, nblks, tag);
268 return (err);
269 }
270 }
271 }
272
273 *numbufsp = nblks;
274 *dbpp = dbp;
275 return (0);
276 }
277
278 static int
279 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
280 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
281 {
282 dnode_t *dn;
283 int err;
284
285 err = dnode_hold(os->os, object, FTAG, &dn);
286 if (err)
287 return (err);
288
289 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
290 numbufsp, dbpp, DMU_READ_PREFETCH);
291
292 dnode_rele(dn, FTAG);
293
294 return (err);
295 }
296
297 int
298 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
299 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
300 {
301 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
302 int err;
303
304 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
305 numbufsp, dbpp, DMU_READ_PREFETCH);
306
307 return (err);
308 }
309
310 void
311 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
312 {
313 int i;
314 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
315
316 if (numbufs == 0)
317 return;
318
319 for (i = 0; i < numbufs; i++) {
320 if (dbp[i])
321 dbuf_rele(dbp[i], tag);
322 }
323
324 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
325 }
326
327 void
328 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
329 {
330 dnode_t *dn;
331 uint64_t blkid;
332 int nblks, i, err;
333
334 if (zfs_prefetch_disable)
335 return;
336
337 if (len == 0) { /* they're interested in the bonus buffer */
338 dn = os->os->os_meta_dnode;
339
340 if (object == 0 || object >= DN_MAX_OBJECT)
341 return;
342
343 rw_enter(&dn->dn_struct_rwlock, RW_READER);
344 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
345 dbuf_prefetch(dn, blkid);
346 rw_exit(&dn->dn_struct_rwlock);
347 return;
348 }
349
350 /*
351 * XXX - Note, if the dnode for the requested object is not
352 * already cached, we will do a *synchronous* read in the
353 * dnode_hold() call. The same is true for any indirects.
354 */
355 err = dnode_hold(os->os, object, FTAG, &dn);
356 if (err != 0)
357 return;
358
359 rw_enter(&dn->dn_struct_rwlock, RW_READER);
360 if (dn->dn_datablkshift) {
361 int blkshift = dn->dn_datablkshift;
362 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
363 P2ALIGN(offset, 1<<blkshift)) >> blkshift;
364 } else {
365 nblks = (offset < dn->dn_datablksz);
366 }
367
368 if (nblks != 0) {
369 blkid = dbuf_whichblock(dn, offset);
370 for (i = 0; i < nblks; i++)
371 dbuf_prefetch(dn, blkid+i);
372 }
373
374 rw_exit(&dn->dn_struct_rwlock);
375
376 dnode_rele(dn, FTAG);
377 }
378
379 static int
380 get_next_chunk(dnode_t *dn, uint64_t *offset, uint64_t limit)
381 {
382 uint64_t len = *offset - limit;
383 uint64_t chunk_len = dn->dn_datablksz * DMU_MAX_DELETEBLKCNT;
384 uint64_t subchunk =
385 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
386
387 ASSERT(limit <= *offset);
388
389 if (len <= chunk_len) {
390 *offset = limit;
391 return (0);
392 }
393
394 ASSERT(ISP2(subchunk));
395
396 while (*offset > limit) {
397 uint64_t initial_offset = P2ROUNDUP(*offset, subchunk);
398 uint64_t delta;
399 int err;
400
401 /* skip over allocated data */
402 err = dnode_next_offset(dn,
403 DNODE_FIND_HOLE|DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
404 if (err == ESRCH)
405 *offset = limit;
406 else if (err)
407 return (err);
408
409 ASSERT3U(*offset, <=, initial_offset);
410 *offset = P2ALIGN(*offset, subchunk);
411 delta = initial_offset - *offset;
412 if (delta >= chunk_len) {
413 *offset += delta - chunk_len;
414 return (0);
415 }
416 chunk_len -= delta;
417
418 /* skip over unallocated data */
419 err = dnode_next_offset(dn,
420 DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
421 if (err == ESRCH)
422 *offset = limit;
423 else if (err)
424 return (err);
425
426 if (*offset < limit)
427 *offset = limit;
428 ASSERT3U(*offset, <, initial_offset);
429 }
430 return (0);
431 }
432
433 static int
434 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
435 uint64_t length, boolean_t free_dnode)
436 {
437 dmu_tx_t *tx;
438 uint64_t object_size, start, end, len;
439 boolean_t trunc = (length == DMU_OBJECT_END);
440 int align, err;
441
442 align = 1 << dn->dn_datablkshift;
443 ASSERT(align > 0);
444 object_size = align == 1 ? dn->dn_datablksz :
445 (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
446
447 end = offset + length;
448 if (trunc || end > object_size)
449 end = object_size;
450 if (end <= offset)
451 return (0);
452 length = end - offset;
453
454 while (length) {
455 start = end;
456 /* assert(offset <= start) */
457 err = get_next_chunk(dn, &start, offset);
458 if (err)
459 return (err);
460 len = trunc ? DMU_OBJECT_END : end - start;
461
462 tx = dmu_tx_create(os);
463 dmu_tx_hold_free(tx, dn->dn_object, start, len);
464 err = dmu_tx_assign(tx, TXG_WAIT);
465 if (err) {
466 dmu_tx_abort(tx);
467 return (err);
468 }
469
470 dnode_free_range(dn, start, trunc ? -1 : len, tx);
471
472 if (start == 0 && free_dnode) {
473 ASSERT(trunc);
474 dnode_free(dn, tx);
475 }
476
477 length -= end - start;
478
479 dmu_tx_commit(tx);
480 end = start;
481 }
482 return (0);
483 }
484
485 int
486 dmu_free_long_range(objset_t *os, uint64_t object,
487 uint64_t offset, uint64_t length)
488 {
489 dnode_t *dn;
490 int err;
491
492 err = dnode_hold(os->os, object, FTAG, &dn);
493 if (err != 0)
494 return (err);
495 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
496 dnode_rele(dn, FTAG);
497 return (err);
498 }
499
500 int
501 dmu_free_object(objset_t *os, uint64_t object)
502 {
503 dnode_t *dn;
504 dmu_tx_t *tx;
505 int err;
506
507 err = dnode_hold_impl(os->os, object, DNODE_MUST_BE_ALLOCATED,
508 FTAG, &dn);
509 if (err != 0)
510 return (err);
511 if (dn->dn_nlevels == 1) {
512 tx = dmu_tx_create(os);
513 dmu_tx_hold_bonus(tx, object);
514 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
515 err = dmu_tx_assign(tx, TXG_WAIT);
516 if (err == 0) {
517 dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
518 dnode_free(dn, tx);
519 dmu_tx_commit(tx);
520 } else {
521 dmu_tx_abort(tx);
522 }
523 } else {
524 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
525 }
526 dnode_rele(dn, FTAG);
527 return (err);
528 }
529
530 int
531 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
532 uint64_t size, dmu_tx_t *tx)
533 {
534 dnode_t *dn;
535 int err = dnode_hold(os->os, object, FTAG, &dn);
536 if (err)
537 return (err);
538 ASSERT(offset < UINT64_MAX);
539 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
540 dnode_free_range(dn, offset, size, tx);
541 dnode_rele(dn, FTAG);
542 return (0);
543 }
544
545 int
546 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
547 void *buf, uint32_t flags)
548 {
549 dnode_t *dn;
550 dmu_buf_t **dbp;
551 int numbufs, i, err;
552
553 err = dnode_hold(os->os, object, FTAG, &dn);
554 if (err)
555 return (err);
556
557 /*
558 * Deal with odd block sizes, where there can't be data past the first
559 * block. If we ever do the tail block optimization, we will need to
560 * handle that here as well.
561 */
562 if (dn->dn_datablkshift == 0) {
563 int newsz = offset > dn->dn_datablksz ? 0 :
564 MIN(size, dn->dn_datablksz - offset);
565 bzero((char *)buf + newsz, size - newsz);
566 size = newsz;
567 }
568
569 while (size > 0) {
570 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
571
572 /*
573 * NB: we could do this block-at-a-time, but it's nice
574 * to be reading in parallel.
575 */
576 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
577 TRUE, FTAG, &numbufs, &dbp, flags);
578 if (err)
579 break;
580
581 for (i = 0; i < numbufs; i++) {
582 int tocpy;
583 int bufoff;
584 dmu_buf_t *db = dbp[i];
585
586 ASSERT(size > 0);
587
588 bufoff = offset - db->db_offset;
589 tocpy = (int)MIN(db->db_size - bufoff, size);
590
591 bcopy((char *)db->db_data + bufoff, buf, tocpy);
592
593 offset += tocpy;
594 size -= tocpy;
595 buf = (char *)buf + tocpy;
596 }
597 dmu_buf_rele_array(dbp, numbufs, FTAG);
598 }
599 dnode_rele(dn, FTAG);
600 return (err);
601 }
602
603 void
604 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
605 const void *buf, dmu_tx_t *tx)
606 {
607 dmu_buf_t **dbp;
608 int numbufs, i;
609
610 if (size == 0)
611 return;
612
613 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
614 FALSE, FTAG, &numbufs, &dbp));
615
616 for (i = 0; i < numbufs; i++) {
617 int tocpy;
618 int bufoff;
619 dmu_buf_t *db = dbp[i];
620
621 ASSERT(size > 0);
622
623 bufoff = offset - db->db_offset;
624 tocpy = (int)MIN(db->db_size - bufoff, size);
625
626 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
627
628 if (tocpy == db->db_size)
629 dmu_buf_will_fill(db, tx);
630 else
631 dmu_buf_will_dirty(db, tx);
632
633 bcopy(buf, (char *)db->db_data + bufoff, tocpy);
634
635 if (tocpy == db->db_size)
636 dmu_buf_fill_done(db, tx);
637
638 offset += tocpy;
639 size -= tocpy;
640 buf = (char *)buf + tocpy;
641 }
642 dmu_buf_rele_array(dbp, numbufs, FTAG);
643 }
644
645 void
646 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
647 dmu_tx_t *tx)
648 {
649 dmu_buf_t **dbp;
650 int numbufs, i;
651
652 if (size == 0)
653 return;
654
655 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
656 FALSE, FTAG, &numbufs, &dbp));
657
658 for (i = 0; i < numbufs; i++) {
659 dmu_buf_t *db = dbp[i];
660
661 dmu_buf_will_not_fill(db, tx);
662 }
663 dmu_buf_rele_array(dbp, numbufs, FTAG);
664 }
665
666 #ifdef _KERNEL
667 int
668 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
669 {
670 dmu_buf_t **dbp;
671 int numbufs, i, err;
672
673 /*
674 * NB: we could do this block-at-a-time, but it's nice
675 * to be reading in parallel.
676 */
677 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
678 &numbufs, &dbp);
679 if (err)
680 return (err);
681
682 for (i = 0; i < numbufs; i++) {
683 int tocpy;
684 int bufoff;
685 dmu_buf_t *db = dbp[i];
686
687 ASSERT(size > 0);
688
689 bufoff = uio->uio_loffset - db->db_offset;
690 tocpy = (int)MIN(db->db_size - bufoff, size);
691
692 err = uiomove((char *)db->db_data + bufoff, tocpy,
693 UIO_READ, uio);
694 if (err)
695 break;
696
697 size -= tocpy;
698 }
699 dmu_buf_rele_array(dbp, numbufs, FTAG);
700
701 return (err);
702 }
703
704 int
705 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
706 dmu_tx_t *tx)
707 {
708 dmu_buf_t **dbp;
709 int numbufs, i;
710 int err = 0;
711
712 if (size == 0)
713 return (0);
714
715 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size,
716 FALSE, FTAG, &numbufs, &dbp);
717 if (err)
718 return (err);
719
720 for (i = 0; i < numbufs; i++) {
721 int tocpy;
722 int bufoff;
723 dmu_buf_t *db = dbp[i];
724
725 ASSERT(size > 0);
726
727 bufoff = uio->uio_loffset - db->db_offset;
728 tocpy = (int)MIN(db->db_size - bufoff, size);
729
730 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
731
732 if (tocpy == db->db_size)
733 dmu_buf_will_fill(db, tx);
734 else
735 dmu_buf_will_dirty(db, tx);
736
737 /*
738 * XXX uiomove could block forever (eg. nfs-backed
739 * pages). There needs to be a uiolockdown() function
740 * to lock the pages in memory, so that uiomove won't
741 * block.
742 */
743 err = uiomove((char *)db->db_data + bufoff, tocpy,
744 UIO_WRITE, uio);
745
746 if (tocpy == db->db_size)
747 dmu_buf_fill_done(db, tx);
748
749 if (err)
750 break;
751
752 size -= tocpy;
753 }
754 dmu_buf_rele_array(dbp, numbufs, FTAG);
755 return (err);
756 }
757
758 int
759 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
760 page_t *pp, dmu_tx_t *tx)
761 {
762 dmu_buf_t **dbp;
763 int numbufs, i;
764 int err;
765
766 if (size == 0)
767 return (0);
768
769 err = dmu_buf_hold_array(os, object, offset, size,
770 FALSE, FTAG, &numbufs, &dbp);
771 if (err)
772 return (err);
773
774 for (i = 0; i < numbufs; i++) {
775 int tocpy, copied, thiscpy;
776 int bufoff;
777 dmu_buf_t *db = dbp[i];
778 caddr_t va;
779
780 ASSERT(size > 0);
781 ASSERT3U(db->db_size, >=, PAGESIZE);
782
783 bufoff = offset - db->db_offset;
784 tocpy = (int)MIN(db->db_size - bufoff, size);
785
786 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
787
788 if (tocpy == db->db_size)
789 dmu_buf_will_fill(db, tx);
790 else
791 dmu_buf_will_dirty(db, tx);
792
793 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
794 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
795 thiscpy = MIN(PAGESIZE, tocpy - copied);
796 va = zfs_map_page(pp, S_READ);
797 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
798 zfs_unmap_page(pp, va);
799 pp = pp->p_next;
800 bufoff += PAGESIZE;
801 }
802
803 if (tocpy == db->db_size)
804 dmu_buf_fill_done(db, tx);
805
806 if (err)
807 break;
808
809 offset += tocpy;
810 size -= tocpy;
811 }
812 dmu_buf_rele_array(dbp, numbufs, FTAG);
813 return (err);
814 }
815 #endif
816
817 /*
818 * Allocate a loaned anonymous arc buffer.
819 */
820 arc_buf_t *
821 dmu_request_arcbuf(dmu_buf_t *handle, int size)
822 {
823 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode;
824
825 return (arc_loan_buf(dn->dn_objset->os_spa, size));
826 }
827
828 /*
829 * Free a loaned arc buffer.
830 */
831 void
832 dmu_return_arcbuf(arc_buf_t *buf)
833 {
834 arc_return_buf(buf, FTAG);
835 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1);
836 }
837
838 /*
839 * When possible directly assign passed loaned arc buffer to a dbuf.
840 * If this is not possible copy the contents of passed arc buf via
841 * dmu_write().
842 */
843 void
844 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
845 dmu_tx_t *tx)
846 {
847 dnode_t *dn = ((dmu_buf_impl_t *)handle)->db_dnode;
848 dmu_buf_impl_t *db;
849 uint32_t blksz = (uint32_t)arc_buf_size(buf);
850 uint64_t blkid;
851
852 rw_enter(&dn->dn_struct_rwlock, RW_READER);
853 blkid = dbuf_whichblock(dn, offset);
854 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
855 rw_exit(&dn->dn_struct_rwlock);
856
857 if (offset == db->db.db_offset && blksz == db->db.db_size) {
858 dbuf_assign_arcbuf(db, buf, tx);
859 dbuf_rele(db, FTAG);
860 } else {
861 dbuf_rele(db, FTAG);
862 ASSERT(dn->dn_objset->os.os == dn->dn_objset);
863 dmu_write(&dn->dn_objset->os, dn->dn_object, offset, blksz,
864 buf->b_data, tx);
865 dmu_return_arcbuf(buf);
866 }
867 }
868
869 typedef struct {
870 dbuf_dirty_record_t *dr;
871 dmu_sync_cb_t *done;
872 void *arg;
873 } dmu_sync_arg_t;
874
875 /* ARGSUSED */
876 static void
877 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
878 {
879 blkptr_t *bp = zio->io_bp;
880
881 if (!BP_IS_HOLE(bp)) {
882 dmu_sync_arg_t *in = varg;
883 dbuf_dirty_record_t *dr = in->dr;
884 dmu_buf_impl_t *db = dr->dr_dbuf;
885 ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type);
886 ASSERT(BP_GET_LEVEL(bp) == 0);
887 bp->blk_fill = 1;
888 }
889 }
890
891 /* ARGSUSED */
892 static void
893 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
894 {
895 dmu_sync_arg_t *in = varg;
896 dbuf_dirty_record_t *dr = in->dr;
897 dmu_buf_impl_t *db = dr->dr_dbuf;
898 dmu_sync_cb_t *done = in->done;
899
900 mutex_enter(&db->db_mtx);
901 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
902 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */
903 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
904 cv_broadcast(&db->db_changed);
905 mutex_exit(&db->db_mtx);
906
907 if (done)
908 done(&(db->db), in->arg);
909
910 kmem_free(in, sizeof (dmu_sync_arg_t));
911 }
912
913 /*
914 * Intent log support: sync the block associated with db to disk.
915 * N.B. and XXX: the caller is responsible for making sure that the
916 * data isn't changing while dmu_sync() is writing it.
917 *
918 * Return values:
919 *
920 * EEXIST: this txg has already been synced, so there's nothing to to.
921 * The caller should not log the write.
922 *
923 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
924 * The caller should not log the write.
925 *
926 * EALREADY: this block is already in the process of being synced.
927 * The caller should track its progress (somehow).
928 *
929 * EINPROGRESS: the IO has been initiated.
930 * The caller should log this blkptr in the callback.
931 *
932 * 0: completed. Sets *bp to the blkptr just written.
933 * The caller should log this blkptr immediately.
934 */
935 int
936 dmu_sync(zio_t *pio, dmu_buf_t *db_fake,
937 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg)
938 {
939 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
940 objset_impl_t *os = db->db_objset;
941 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool;
942 tx_state_t *tx = &dp->dp_tx;
943 dbuf_dirty_record_t *dr;
944 dmu_sync_arg_t *in;
945 zbookmark_t zb;
946 writeprops_t wp = { 0 };
947 zio_t *zio;
948 int err;
949
950 ASSERT(BP_IS_HOLE(bp));
951 ASSERT(txg != 0);
952
953 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n",
954 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg);
955
956 /*
957 * XXX - would be nice if we could do this without suspending...
958 */
959 txg_suspend(dp);
960
961 /*
962 * If this txg already synced, there's nothing to do.
963 */
964 if (txg <= tx->tx_synced_txg) {
965 txg_resume(dp);
966 /*
967 * If we're running ziltest, we need the blkptr regardless.
968 */
969 if (txg > spa_freeze_txg(dp->dp_spa)) {
970 /* if db_blkptr == NULL, this was an empty write */
971 if (db->db_blkptr)
972 *bp = *db->db_blkptr; /* structure assignment */
973 return (0);
974 }
975 return (EEXIST);
976 }
977
978 mutex_enter(&db->db_mtx);
979
980 if (txg == tx->tx_syncing_txg) {
981 while (db->db_data_pending) {
982 /*
983 * IO is in-progress. Wait for it to finish.
984 * XXX - would be nice to be able to somehow "attach"
985 * this zio to the parent zio passed in.
986 */
987 cv_wait(&db->db_changed, &db->db_mtx);
988 if (!db->db_data_pending &&
989 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) {
990 /*
991 * IO was compressed away
992 */
993 *bp = *db->db_blkptr; /* structure assignment */
994 mutex_exit(&db->db_mtx);
995 txg_resume(dp);
996 return (0);
997 }
998 ASSERT(db->db_data_pending ||
999 (db->db_blkptr && db->db_blkptr->blk_birth == txg));
1000 }
1001
1002 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) {
1003 /*
1004 * IO is already completed.
1005 */
1006 *bp = *db->db_blkptr; /* structure assignment */
1007 mutex_exit(&db->db_mtx);
1008 txg_resume(dp);
1009 return (0);
1010 }
1011 }
1012
1013 dr = db->db_last_dirty;
1014 while (dr && dr->dr_txg > txg)
1015 dr = dr->dr_next;
1016 if (dr == NULL || dr->dr_txg < txg) {
1017 /*
1018 * This dbuf isn't dirty, must have been free_range'd.
1019 * There's no need to log writes to freed blocks, so we're done.
1020 */
1021 mutex_exit(&db->db_mtx);
1022 txg_resume(dp);
1023 return (ENOENT);
1024 }
1025
1026 ASSERT(dr->dr_txg == txg);
1027 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) {
1028 /*
1029 * We have already issued a sync write for this buffer.
1030 */
1031 mutex_exit(&db->db_mtx);
1032 txg_resume(dp);
1033 return (EALREADY);
1034 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
1035 /*
1036 * This buffer has already been synced. It could not
1037 * have been dirtied since, or we would have cleared the state.
1038 */
1039 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */
1040 mutex_exit(&db->db_mtx);
1041 txg_resume(dp);
1042 return (0);
1043 }
1044
1045 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
1046 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1047 in->dr = dr;
1048 in->done = done;
1049 in->arg = arg;
1050 mutex_exit(&db->db_mtx);
1051 txg_resume(dp);
1052
1053 zb.zb_objset = os->os_dsl_dataset->ds_object;
1054 zb.zb_object = db->db.db_object;
1055 zb.zb_level = db->db_level;
1056 zb.zb_blkid = db->db_blkid;
1057
1058 wp.wp_type = db->db_dnode->dn_type;
1059 wp.wp_level = db->db_level;
1060 wp.wp_copies = os->os_copies;
1061 wp.wp_dnchecksum = db->db_dnode->dn_checksum;
1062 wp.wp_oschecksum = os->os_checksum;
1063 wp.wp_dncompress = db->db_dnode->dn_compress;
1064 wp.wp_oscompress = os->os_compress;
1065
1066 ASSERT(BP_IS_HOLE(bp));
1067
1068 zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db),
1069 txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in,
1070 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
1071 if (pio) {
1072 zio_nowait(zio);
1073 err = EINPROGRESS;
1074 } else {
1075 err = zio_wait(zio);
1076 ASSERT(err == 0);
1077 }
1078 return (err);
1079 }
1080
1081 int
1082 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1083 dmu_tx_t *tx)
1084 {
1085 dnode_t *dn;
1086 int err;
1087
1088 err = dnode_hold(os->os, object, FTAG, &dn);
1089 if (err)
1090 return (err);
1091 err = dnode_set_blksz(dn, size, ibs, tx);
1092 dnode_rele(dn, FTAG);
1093 return (err);
1094 }
1095
1096 void
1097 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1098 dmu_tx_t *tx)
1099 {
1100 dnode_t *dn;
1101
1102 /* XXX assumes dnode_hold will not get an i/o error */
1103 (void) dnode_hold(os->os, object, FTAG, &dn);
1104 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1105 dn->dn_checksum = checksum;
1106 dnode_setdirty(dn, tx);
1107 dnode_rele(dn, FTAG);
1108 }
1109
1110 void
1111 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1112 dmu_tx_t *tx)
1113 {
1114 dnode_t *dn;
1115
1116 /* XXX assumes dnode_hold will not get an i/o error */
1117 (void) dnode_hold(os->os, object, FTAG, &dn);
1118 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1119 dn->dn_compress = compress;
1120 dnode_setdirty(dn, tx);
1121 dnode_rele(dn, FTAG);
1122 }
1123
1124 int
1125 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1126 {
1127 dnode_t *dn;
1128 int i, err;
1129
1130 err = dnode_hold(os->os, object, FTAG, &dn);
1131 if (err)
1132 return (err);
1133 /*
1134 * Sync any current changes before
1135 * we go trundling through the block pointers.
1136 */
1137 for (i = 0; i < TXG_SIZE; i++) {
1138 if (list_link_active(&dn->dn_dirty_link[i]))
1139 break;
1140 }
1141 if (i != TXG_SIZE) {
1142 dnode_rele(dn, FTAG);
1143 txg_wait_synced(dmu_objset_pool(os), 0);
1144 err = dnode_hold(os->os, object, FTAG, &dn);
1145 if (err)
1146 return (err);
1147 }
1148
1149 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1150 dnode_rele(dn, FTAG);
1151
1152 return (err);
1153 }
1154
1155 void
1156 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1157 {
1158 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1159 mutex_enter(&dn->dn_mtx);
1160
1161 doi->doi_data_block_size = dn->dn_datablksz;
1162 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1163 1ULL << dn->dn_indblkshift : 0;
1164 doi->doi_indirection = dn->dn_nlevels;
1165 doi->doi_checksum = dn->dn_checksum;
1166 doi->doi_compress = dn->dn_compress;
1167 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) +
1168 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT;
1169 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid;
1170 doi->doi_type = dn->dn_type;
1171 doi->doi_bonus_size = dn->dn_bonuslen;
1172 doi->doi_bonus_type = dn->dn_bonustype;
1173
1174 mutex_exit(&dn->dn_mtx);
1175 rw_exit(&dn->dn_struct_rwlock);
1176 }
1177
1178 /*
1179 * Get information on a DMU object.
1180 * If doi is NULL, just indicates whether the object exists.
1181 */
1182 int
1183 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1184 {
1185 dnode_t *dn;
1186 int err = dnode_hold(os->os, object, FTAG, &dn);
1187
1188 if (err)
1189 return (err);
1190
1191 if (doi != NULL)
1192 dmu_object_info_from_dnode(dn, doi);
1193
1194 dnode_rele(dn, FTAG);
1195 return (0);
1196 }
1197
1198 /*
1199 * As above, but faster; can be used when you have a held dbuf in hand.
1200 */
1201 void
1202 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi)
1203 {
1204 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi);
1205 }
1206
1207 /*
1208 * Faster still when you only care about the size.
1209 * This is specifically optimized for zfs_getattr().
1210 */
1211 void
1212 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512)
1213 {
1214 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
1215
1216 *blksize = dn->dn_datablksz;
1217 /* add 1 for dnode space */
1218 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1219 SPA_MINBLOCKSHIFT) + 1;
1220 }
1221
1222 void
1223 byteswap_uint64_array(void *vbuf, size_t size)
1224 {
1225 uint64_t *buf = vbuf;
1226 size_t count = size >> 3;
1227 int i;
1228
1229 ASSERT((size & 7) == 0);
1230
1231 for (i = 0; i < count; i++)
1232 buf[i] = BSWAP_64(buf[i]);
1233 }
1234
1235 void
1236 byteswap_uint32_array(void *vbuf, size_t size)
1237 {
1238 uint32_t *buf = vbuf;
1239 size_t count = size >> 2;
1240 int i;
1241
1242 ASSERT((size & 3) == 0);
1243
1244 for (i = 0; i < count; i++)
1245 buf[i] = BSWAP_32(buf[i]);
1246 }
1247
1248 void
1249 byteswap_uint16_array(void *vbuf, size_t size)
1250 {
1251 uint16_t *buf = vbuf;
1252 size_t count = size >> 1;
1253 int i;
1254
1255 ASSERT((size & 1) == 0);
1256
1257 for (i = 0; i < count; i++)
1258 buf[i] = BSWAP_16(buf[i]);
1259 }
1260
1261 /* ARGSUSED */
1262 void
1263 byteswap_uint8_array(void *vbuf, size_t size)
1264 {
1265 }
1266
1267 void
1268 dmu_init(void)
1269 {
1270 dbuf_init();
1271 dnode_init();
1272 arc_init();
1273 l2arc_init();
1274 }
1275
1276 void
1277 dmu_fini(void)
1278 {
1279 arc_fini();
1280 dnode_fini();
1281 dbuf_fini();
1282 l2arc_fini();
1283 }
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