Patrick Welche <prlw1@cam.ac.uk>
[netbsd-mini2440.git] / external / cddl / osnet / dist / uts / common / fs / zfs / dmu.c
blobf3c2b37f4d47114e43740e32cb7a7d2f46e4c8c0
1 /*
2 * CDDL HEADER START
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.
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.
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]
19 * CDDL HEADER END
22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
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
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" },
90 int
91 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
92 void *tag, dmu_buf_t **dbp)
94 dnode_t *dn;
95 uint64_t blkid;
96 dmu_buf_impl_t *db;
97 int err;
99 err = dnode_hold(os->os, object, FTAG, &dn);
100 if (err)
101 return (err);
102 blkid = dbuf_whichblock(dn, offset);
103 rw_enter(&dn->dn_struct_rwlock, RW_READER);
104 db = dbuf_hold(dn, blkid, tag);
105 rw_exit(&dn->dn_struct_rwlock);
106 if (db == NULL) {
107 err = EIO;
108 } else {
109 err = dbuf_read(db, NULL, DB_RF_CANFAIL);
110 if (err) {
111 dbuf_rele(db, tag);
112 db = NULL;
116 dnode_rele(dn, FTAG);
117 *dbp = &db->db;
118 return (err);
122 dmu_bonus_max(void)
124 return (DN_MAX_BONUSLEN);
128 dmu_set_bonus(dmu_buf_t *db, int newsize, dmu_tx_t *tx)
130 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
132 if (dn->dn_bonus != (dmu_buf_impl_t *)db)
133 return (EINVAL);
134 if (newsize < 0 || newsize > db->db_size)
135 return (EINVAL);
136 dnode_setbonuslen(dn, newsize, tx);
137 return (0);
141 * returns ENOENT, EIO, or 0.
144 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
146 dnode_t *dn;
147 dmu_buf_impl_t *db;
148 int error;
150 error = dnode_hold(os->os, object, FTAG, &dn);
151 if (error)
152 return (error);
154 rw_enter(&dn->dn_struct_rwlock, RW_READER);
155 if (dn->dn_bonus == NULL) {
156 rw_exit(&dn->dn_struct_rwlock);
157 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
158 if (dn->dn_bonus == NULL)
159 dbuf_create_bonus(dn);
161 db = dn->dn_bonus;
162 rw_exit(&dn->dn_struct_rwlock);
164 /* as long as the bonus buf is held, the dnode will be held */
165 if (refcount_add(&db->db_holds, tag) == 1)
166 VERIFY(dnode_add_ref(dn, db));
168 dnode_rele(dn, FTAG);
170 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED));
172 *dbp = &db->db;
173 return (0);
177 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
178 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
179 * and can induce severe lock contention when writing to several files
180 * whose dnodes are in the same block.
182 static int
183 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset,
184 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
186 dsl_pool_t *dp = NULL;
187 dmu_buf_t **dbp;
188 uint64_t blkid, nblks, i;
189 uint32_t flags;
190 int err;
191 zio_t *zio;
192 hrtime_t start;
194 ASSERT(length <= DMU_MAX_ACCESS);
196 flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT;
197 if (length > zfetch_array_rd_sz)
198 flags |= DB_RF_NOPREFETCH;
200 rw_enter(&dn->dn_struct_rwlock, RW_READER);
201 if (dn->dn_datablkshift) {
202 int blkshift = dn->dn_datablkshift;
203 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
204 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
205 } else {
206 if (offset + length > dn->dn_datablksz) {
207 zfs_panic_recover("zfs: accessing past end of object "
208 "%llx/%llx (size=%u access=%llu+%llu)",
209 (longlong_t)dn->dn_objset->
210 os_dsl_dataset->ds_object,
211 (longlong_t)dn->dn_object, dn->dn_datablksz,
212 (longlong_t)offset, (longlong_t)length);
213 return (EIO);
215 nblks = 1;
217 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
219 if (dn->dn_objset->os_dsl_dataset)
220 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
221 if (dp && dsl_pool_sync_context(dp))
222 start = gethrtime();
223 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
224 blkid = dbuf_whichblock(dn, offset);
225 for (i = 0; i < nblks; i++) {
226 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
227 if (db == NULL) {
228 rw_exit(&dn->dn_struct_rwlock);
229 dmu_buf_rele_array(dbp, nblks, tag);
230 zio_nowait(zio);
231 return (EIO);
233 /* initiate async i/o */
234 if (read) {
235 rw_exit(&dn->dn_struct_rwlock);
236 (void) dbuf_read(db, zio, flags);
237 rw_enter(&dn->dn_struct_rwlock, RW_READER);
239 dbp[i] = &db->db;
241 rw_exit(&dn->dn_struct_rwlock);
243 /* wait for async i/o */
244 err = zio_wait(zio);
245 /* track read overhead when we are in sync context */
246 if (dp && dsl_pool_sync_context(dp))
247 dp->dp_read_overhead += gethrtime() - start;
248 if (err) {
249 dmu_buf_rele_array(dbp, nblks, tag);
250 return (err);
253 /* wait for other io to complete */
254 if (read) {
255 for (i = 0; i < nblks; i++) {
256 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
257 mutex_enter(&db->db_mtx);
258 while (db->db_state == DB_READ ||
259 db->db_state == DB_FILL)
260 cv_wait(&db->db_changed, &db->db_mtx);
261 if (db->db_state == DB_UNCACHED)
262 err = EIO;
263 mutex_exit(&db->db_mtx);
264 if (err) {
265 dmu_buf_rele_array(dbp, nblks, tag);
266 return (err);
271 *numbufsp = nblks;
272 *dbpp = dbp;
273 return (0);
276 static int
277 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
278 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
280 dnode_t *dn;
281 int err;
283 err = dnode_hold(os->os, object, FTAG, &dn);
284 if (err)
285 return (err);
287 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
288 numbufsp, dbpp);
290 dnode_rele(dn, FTAG);
292 return (err);
296 dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
297 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
299 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
300 int err;
302 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
303 numbufsp, dbpp);
305 return (err);
308 void
309 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
311 int i;
312 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
314 if (numbufs == 0)
315 return;
317 for (i = 0; i < numbufs; i++) {
318 if (dbp[i])
319 dbuf_rele(dbp[i], tag);
322 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
325 void
326 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
328 dnode_t *dn;
329 uint64_t blkid;
330 int nblks, i, err;
332 if (zfs_prefetch_disable)
333 return;
335 if (len == 0) { /* they're interested in the bonus buffer */
336 dn = os->os->os_meta_dnode;
338 if (object == 0 || object >= DN_MAX_OBJECT)
339 return;
341 rw_enter(&dn->dn_struct_rwlock, RW_READER);
342 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
343 dbuf_prefetch(dn, blkid);
344 rw_exit(&dn->dn_struct_rwlock);
345 return;
349 * XXX - Note, if the dnode for the requested object is not
350 * already cached, we will do a *synchronous* read in the
351 * dnode_hold() call. The same is true for any indirects.
353 err = dnode_hold(os->os, object, FTAG, &dn);
354 if (err != 0)
355 return;
357 rw_enter(&dn->dn_struct_rwlock, RW_READER);
358 if (dn->dn_datablkshift) {
359 int blkshift = dn->dn_datablkshift;
360 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
361 P2ALIGN(offset, 1<<blkshift)) >> blkshift;
362 } else {
363 nblks = (offset < dn->dn_datablksz);
366 if (nblks != 0) {
367 blkid = dbuf_whichblock(dn, offset);
368 for (i = 0; i < nblks; i++)
369 dbuf_prefetch(dn, blkid+i);
372 rw_exit(&dn->dn_struct_rwlock);
374 dnode_rele(dn, FTAG);
377 static int
378 get_next_chunk(dnode_t *dn, uint64_t *offset, uint64_t limit)
380 uint64_t len = *offset - limit;
381 uint64_t chunk_len = dn->dn_datablksz * DMU_MAX_DELETEBLKCNT;
382 uint64_t subchunk =
383 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
385 ASSERT(limit <= *offset);
387 if (len <= chunk_len) {
388 *offset = limit;
389 return (0);
392 ASSERT(ISP2(subchunk));
394 while (*offset > limit) {
395 uint64_t initial_offset = P2ROUNDUP(*offset, subchunk);
396 uint64_t delta;
397 int err;
399 /* skip over allocated data */
400 err = dnode_next_offset(dn,
401 DNODE_FIND_HOLE|DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
402 if (err == ESRCH)
403 *offset = limit;
404 else if (err)
405 return (err);
407 ASSERT3U(*offset, <=, initial_offset);
408 *offset = P2ALIGN(*offset, subchunk);
409 delta = initial_offset - *offset;
410 if (delta >= chunk_len) {
411 *offset += delta - chunk_len;
412 return (0);
414 chunk_len -= delta;
416 /* skip over unallocated data */
417 err = dnode_next_offset(dn,
418 DNODE_FIND_BACKWARDS, offset, 1, 1, 0);
419 if (err == ESRCH)
420 *offset = limit;
421 else if (err)
422 return (err);
424 if (*offset < limit)
425 *offset = limit;
426 ASSERT3U(*offset, <, initial_offset);
428 return (0);
431 static int
432 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
433 uint64_t length, boolean_t free_dnode)
435 dmu_tx_t *tx;
436 uint64_t object_size, start, end, len;
437 boolean_t trunc = (length == DMU_OBJECT_END);
438 int align, err;
440 align = 1 << dn->dn_datablkshift;
441 ASSERT(align > 0);
442 object_size = align == 1 ? dn->dn_datablksz :
443 (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
445 if (trunc || (end = offset + length) > object_size)
446 end = object_size;
447 if (end <= offset)
448 return (0);
449 length = end - offset;
451 while (length) {
452 start = end;
453 err = get_next_chunk(dn, &start, offset);
454 if (err)
455 return (err);
456 len = trunc ? DMU_OBJECT_END : end - start;
458 tx = dmu_tx_create(os);
459 dmu_tx_hold_free(tx, dn->dn_object, start, len);
460 err = dmu_tx_assign(tx, TXG_WAIT);
461 if (err) {
462 dmu_tx_abort(tx);
463 return (err);
466 dnode_free_range(dn, start, trunc ? -1 : len, tx);
468 if (start == 0 && free_dnode) {
469 ASSERT(trunc);
470 dnode_free(dn, tx);
473 length -= end - start;
475 dmu_tx_commit(tx);
476 end = start;
478 return (0);
482 dmu_free_long_range(objset_t *os, uint64_t object,
483 uint64_t offset, uint64_t length)
485 dnode_t *dn;
486 int err;
488 err = dnode_hold(os->os, object, FTAG, &dn);
489 if (err != 0)
490 return (err);
491 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
492 dnode_rele(dn, FTAG);
493 return (err);
497 dmu_free_object(objset_t *os, uint64_t object)
499 dnode_t *dn;
500 dmu_tx_t *tx;
501 int err;
503 err = dnode_hold_impl(os->os, object, DNODE_MUST_BE_ALLOCATED,
504 FTAG, &dn);
505 if (err != 0)
506 return (err);
507 if (dn->dn_nlevels == 1) {
508 tx = dmu_tx_create(os);
509 dmu_tx_hold_bonus(tx, object);
510 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
511 err = dmu_tx_assign(tx, TXG_WAIT);
512 if (err == 0) {
513 dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
514 dnode_free(dn, tx);
515 dmu_tx_commit(tx);
516 } else {
517 dmu_tx_abort(tx);
519 } else {
520 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
522 dnode_rele(dn, FTAG);
523 return (err);
527 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
528 uint64_t size, dmu_tx_t *tx)
530 dnode_t *dn;
531 int err = dnode_hold(os->os, object, FTAG, &dn);
532 if (err)
533 return (err);
534 ASSERT(offset < UINT64_MAX);
535 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
536 dnode_free_range(dn, offset, size, tx);
537 dnode_rele(dn, FTAG);
538 return (0);
542 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
543 void *buf)
545 dnode_t *dn;
546 dmu_buf_t **dbp;
547 int numbufs, i, err;
549 err = dnode_hold(os->os, object, FTAG, &dn);
550 if (err)
551 return (err);
554 * Deal with odd block sizes, where there can't be data past the first
555 * block. If we ever do the tail block optimization, we will need to
556 * handle that here as well.
558 if (dn->dn_datablkshift == 0) {
559 int newsz = offset > dn->dn_datablksz ? 0 :
560 MIN(size, dn->dn_datablksz - offset);
561 bzero((char *)buf + newsz, size - newsz);
562 size = newsz;
565 while (size > 0) {
566 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
569 * NB: we could do this block-at-a-time, but it's nice
570 * to be reading in parallel.
572 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
573 TRUE, FTAG, &numbufs, &dbp);
574 if (err)
575 break;
577 for (i = 0; i < numbufs; i++) {
578 int tocpy;
579 int bufoff;
580 dmu_buf_t *db = dbp[i];
582 ASSERT(size > 0);
584 bufoff = offset - db->db_offset;
585 tocpy = (int)MIN(db->db_size - bufoff, size);
587 bcopy((char *)db->db_data + bufoff, buf, tocpy);
589 offset += tocpy;
590 size -= tocpy;
591 buf = (char *)buf + tocpy;
593 dmu_buf_rele_array(dbp, numbufs, FTAG);
595 dnode_rele(dn, FTAG);
596 return (err);
599 void
600 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
601 const void *buf, dmu_tx_t *tx)
603 dmu_buf_t **dbp;
604 int numbufs, i;
606 if (size == 0)
607 return;
609 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
610 FALSE, FTAG, &numbufs, &dbp));
612 for (i = 0; i < numbufs; i++) {
613 int tocpy;
614 int bufoff;
615 dmu_buf_t *db = dbp[i];
617 ASSERT(size > 0);
619 bufoff = offset - db->db_offset;
620 tocpy = (int)MIN(db->db_size - bufoff, size);
622 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
624 if (tocpy == db->db_size)
625 dmu_buf_will_fill(db, tx);
626 else
627 dmu_buf_will_dirty(db, tx);
629 bcopy(buf, (char *)db->db_data + bufoff, tocpy);
631 if (tocpy == db->db_size)
632 dmu_buf_fill_done(db, tx);
634 offset += tocpy;
635 size -= tocpy;
636 buf = (char *)buf + tocpy;
638 dmu_buf_rele_array(dbp, numbufs, FTAG);
641 void
642 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
643 dmu_tx_t *tx)
645 dmu_buf_t **dbp;
646 int numbufs, i;
648 if (size == 0)
649 return;
651 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
652 FALSE, FTAG, &numbufs, &dbp));
654 for (i = 0; i < numbufs; i++) {
655 dmu_buf_t *db = dbp[i];
657 dmu_buf_will_not_fill(db, tx);
659 dmu_buf_rele_array(dbp, numbufs, FTAG);
662 #ifdef _KERNEL
664 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
666 dmu_buf_t **dbp;
667 int numbufs, i, err;
670 * NB: we could do this block-at-a-time, but it's nice
671 * to be reading in parallel.
673 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
674 &numbufs, &dbp);
675 if (err)
676 return (err);
678 for (i = 0; i < numbufs; i++) {
679 int tocpy;
680 int bufoff;
681 dmu_buf_t *db = dbp[i];
683 ASSERT(size > 0);
685 bufoff = uio->uio_loffset - db->db_offset;
686 tocpy = (int)MIN(db->db_size - bufoff, size);
688 err = uiomove((char *)db->db_data + bufoff, tocpy,
689 UIO_READ, uio);
690 if (err)
691 break;
693 size -= tocpy;
695 dmu_buf_rele_array(dbp, numbufs, FTAG);
697 return (err);
701 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
702 dmu_tx_t *tx)
704 dmu_buf_t **dbp;
705 int numbufs, i;
706 int err = 0;
708 if (size == 0)
709 return (0);
711 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size,
712 FALSE, FTAG, &numbufs, &dbp);
713 if (err)
714 return (err);
716 for (i = 0; i < numbufs; i++) {
717 int tocpy;
718 int bufoff;
719 dmu_buf_t *db = dbp[i];
721 ASSERT(size > 0);
723 bufoff = uio->uio_loffset - db->db_offset;
724 tocpy = (int)MIN(db->db_size - bufoff, size);
726 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
728 if (tocpy == db->db_size)
729 dmu_buf_will_fill(db, tx);
730 else
731 dmu_buf_will_dirty(db, tx);
734 * XXX uiomove could block forever (eg. nfs-backed
735 * pages). There needs to be a uiolockdown() function
736 * to lock the pages in memory, so that uiomove won't
737 * block.
739 err = uiomove((char *)db->db_data + bufoff, tocpy,
740 UIO_WRITE, uio);
742 if (tocpy == db->db_size)
743 dmu_buf_fill_done(db, tx);
745 if (err)
746 break;
748 size -= tocpy;
750 dmu_buf_rele_array(dbp, numbufs, FTAG);
751 return (err);
754 #ifndef __NetBSD__
756 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
757 page_t *pp, dmu_tx_t *tx)
759 dmu_buf_t **dbp;
760 int numbufs, i;
761 int err;
763 if (size == 0)
764 return (0);
766 err = dmu_buf_hold_array(os, object, offset, size,
767 FALSE, FTAG, &numbufs, &dbp);
768 if (err)
769 return (err);
771 for (i = 0; i < numbufs; i++) {
772 int tocpy, copied, thiscpy;
773 int bufoff;
774 dmu_buf_t *db = dbp[i];
775 caddr_t va;
777 ASSERT(size > 0);
778 ASSERT3U(db->db_size, >=, PAGESIZE);
780 bufoff = offset - db->db_offset;
781 tocpy = (int)MIN(db->db_size - bufoff, size);
783 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
785 if (tocpy == db->db_size)
786 dmu_buf_will_fill(db, tx);
787 else
788 dmu_buf_will_dirty(db, tx);
790 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
791 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
792 thiscpy = MIN(PAGESIZE, tocpy - copied);
793 va = zfs_map_page(pp, S_READ);
794 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
795 zfs_unmap_page(pp, va);
796 pp = pp->p_next;
797 bufoff += PAGESIZE;
800 if (tocpy == db->db_size)
801 dmu_buf_fill_done(db, tx);
803 if (err)
804 break;
806 offset += tocpy;
807 size -= tocpy;
809 dmu_buf_rele_array(dbp, numbufs, FTAG);
810 return (err);
812 #endif /* __NetBSD__ */
813 #endif
815 typedef struct {
816 dbuf_dirty_record_t *dr;
817 dmu_sync_cb_t *done;
818 void *arg;
819 } dmu_sync_arg_t;
821 /* ARGSUSED */
822 static void
823 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
825 blkptr_t *bp = zio->io_bp;
827 if (!BP_IS_HOLE(bp)) {
828 dmu_sync_arg_t *in = varg;
829 dbuf_dirty_record_t *dr = in->dr;
830 dmu_buf_impl_t *db = dr->dr_dbuf;
831 ASSERT(BP_GET_TYPE(bp) == db->db_dnode->dn_type);
832 ASSERT(BP_GET_LEVEL(bp) == 0);
833 bp->blk_fill = 1;
837 /* ARGSUSED */
838 static void
839 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
841 dmu_sync_arg_t *in = varg;
842 dbuf_dirty_record_t *dr = in->dr;
843 dmu_buf_impl_t *db = dr->dr_dbuf;
844 dmu_sync_cb_t *done = in->done;
846 mutex_enter(&db->db_mtx);
847 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
848 dr->dt.dl.dr_overridden_by = *zio->io_bp; /* structure assignment */
849 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
850 cv_broadcast(&db->db_changed);
851 mutex_exit(&db->db_mtx);
853 if (done)
854 done(&(db->db), in->arg);
856 kmem_free(in, sizeof (dmu_sync_arg_t));
860 * Intent log support: sync the block associated with db to disk.
861 * N.B. and XXX: the caller is responsible for making sure that the
862 * data isn't changing while dmu_sync() is writing it.
864 * Return values:
866 * EEXIST: this txg has already been synced, so there's nothing to to.
867 * The caller should not log the write.
869 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
870 * The caller should not log the write.
872 * EALREADY: this block is already in the process of being synced.
873 * The caller should track its progress (somehow).
875 * EINPROGRESS: the IO has been initiated.
876 * The caller should log this blkptr in the callback.
878 * 0: completed. Sets *bp to the blkptr just written.
879 * The caller should log this blkptr immediately.
882 dmu_sync(zio_t *pio, dmu_buf_t *db_fake,
883 blkptr_t *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg)
885 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
886 objset_impl_t *os = db->db_objset;
887 dsl_pool_t *dp = os->os_dsl_dataset->ds_dir->dd_pool;
888 tx_state_t *tx = &dp->dp_tx;
889 dbuf_dirty_record_t *dr;
890 dmu_sync_arg_t *in;
891 zbookmark_t zb;
892 writeprops_t wp = { 0 };
893 zio_t *zio;
894 int err;
896 ASSERT(BP_IS_HOLE(bp));
897 ASSERT(txg != 0);
899 dprintf("dmu_sync txg=%llu, s,o,q %llu %llu %llu\n",
900 txg, tx->tx_synced_txg, tx->tx_open_txg, tx->tx_quiesced_txg);
903 * XXX - would be nice if we could do this without suspending...
905 txg_suspend(dp);
908 * If this txg already synced, there's nothing to do.
910 if (txg <= tx->tx_synced_txg) {
911 txg_resume(dp);
913 * If we're running ziltest, we need the blkptr regardless.
915 if (txg > spa_freeze_txg(dp->dp_spa)) {
916 /* if db_blkptr == NULL, this was an empty write */
917 if (db->db_blkptr)
918 *bp = *db->db_blkptr; /* structure assignment */
919 return (0);
921 return (EEXIST);
924 mutex_enter(&db->db_mtx);
926 if (txg == tx->tx_syncing_txg) {
927 while (db->db_data_pending) {
929 * IO is in-progress. Wait for it to finish.
930 * XXX - would be nice to be able to somehow "attach"
931 * this zio to the parent zio passed in.
933 cv_wait(&db->db_changed, &db->db_mtx);
934 if (!db->db_data_pending &&
935 db->db_blkptr && BP_IS_HOLE(db->db_blkptr)) {
937 * IO was compressed away
939 *bp = *db->db_blkptr; /* structure assignment */
940 mutex_exit(&db->db_mtx);
941 txg_resume(dp);
942 return (0);
944 ASSERT(db->db_data_pending ||
945 (db->db_blkptr && db->db_blkptr->blk_birth == txg));
948 if (db->db_blkptr && db->db_blkptr->blk_birth == txg) {
950 * IO is already completed.
952 *bp = *db->db_blkptr; /* structure assignment */
953 mutex_exit(&db->db_mtx);
954 txg_resume(dp);
955 return (0);
959 dr = db->db_last_dirty;
960 while (dr && dr->dr_txg > txg)
961 dr = dr->dr_next;
962 if (dr == NULL || dr->dr_txg < txg) {
964 * This dbuf isn't dirty, must have been free_range'd.
965 * There's no need to log writes to freed blocks, so we're done.
967 mutex_exit(&db->db_mtx);
968 txg_resume(dp);
969 return (ENOENT);
972 ASSERT(dr->dr_txg == txg);
973 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC) {
975 * We have already issued a sync write for this buffer.
977 mutex_exit(&db->db_mtx);
978 txg_resume(dp);
979 return (EALREADY);
980 } else if (dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
982 * This buffer has already been synced. It could not
983 * have been dirtied since, or we would have cleared the state.
985 *bp = dr->dt.dl.dr_overridden_by; /* structure assignment */
986 mutex_exit(&db->db_mtx);
987 txg_resume(dp);
988 return (0);
991 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
992 in = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
993 in->dr = dr;
994 in->done = done;
995 in->arg = arg;
996 mutex_exit(&db->db_mtx);
997 txg_resume(dp);
999 zb.zb_objset = os->os_dsl_dataset->ds_object;
1000 zb.zb_object = db->db.db_object;
1001 zb.zb_level = db->db_level;
1002 zb.zb_blkid = db->db_blkid;
1004 wp.wp_type = db->db_dnode->dn_type;
1005 wp.wp_level = db->db_level;
1006 wp.wp_copies = os->os_copies;
1007 wp.wp_dnchecksum = db->db_dnode->dn_checksum;
1008 wp.wp_oschecksum = os->os_checksum;
1009 wp.wp_dncompress = db->db_dnode->dn_compress;
1010 wp.wp_oscompress = os->os_compress;
1012 ASSERT(BP_IS_HOLE(bp));
1014 zio = arc_write(pio, os->os_spa, &wp, DBUF_IS_L2CACHEABLE(db),
1015 txg, bp, dr->dt.dl.dr_data, dmu_sync_ready, dmu_sync_done, in,
1016 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
1017 if (pio) {
1018 zio_nowait(zio);
1019 err = EINPROGRESS;
1020 } else {
1021 err = zio_wait(zio);
1022 ASSERT(err == 0);
1024 return (err);
1028 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1029 dmu_tx_t *tx)
1031 dnode_t *dn;
1032 int err;
1034 err = dnode_hold(os->os, object, FTAG, &dn);
1035 if (err)
1036 return (err);
1037 err = dnode_set_blksz(dn, size, ibs, tx);
1038 dnode_rele(dn, FTAG);
1039 return (err);
1042 void
1043 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1044 dmu_tx_t *tx)
1046 dnode_t *dn;
1048 /* XXX assumes dnode_hold will not get an i/o error */
1049 (void) dnode_hold(os->os, object, FTAG, &dn);
1050 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1051 dn->dn_checksum = checksum;
1052 dnode_setdirty(dn, tx);
1053 dnode_rele(dn, FTAG);
1056 void
1057 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1058 dmu_tx_t *tx)
1060 dnode_t *dn;
1062 /* XXX assumes dnode_hold will not get an i/o error */
1063 (void) dnode_hold(os->os, object, FTAG, &dn);
1064 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1065 dn->dn_compress = compress;
1066 dnode_setdirty(dn, tx);
1067 dnode_rele(dn, FTAG);
1071 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1073 dnode_t *dn;
1074 int i, err;
1076 err = dnode_hold(os->os, object, FTAG, &dn);
1077 if (err)
1078 return (err);
1080 * Sync any current changes before
1081 * we go trundling through the block pointers.
1083 for (i = 0; i < TXG_SIZE; i++) {
1084 if (list_link_active(&dn->dn_dirty_link[i]))
1085 break;
1087 if (i != TXG_SIZE) {
1088 dnode_rele(dn, FTAG);
1089 txg_wait_synced(dmu_objset_pool(os), 0);
1090 err = dnode_hold(os->os, object, FTAG, &dn);
1091 if (err)
1092 return (err);
1095 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1096 dnode_rele(dn, FTAG);
1098 return (err);
1101 void
1102 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1104 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1105 mutex_enter(&dn->dn_mtx);
1107 doi->doi_data_block_size = dn->dn_datablksz;
1108 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1109 1ULL << dn->dn_indblkshift : 0;
1110 doi->doi_indirection = dn->dn_nlevels;
1111 doi->doi_checksum = dn->dn_checksum;
1112 doi->doi_compress = dn->dn_compress;
1113 doi->doi_physical_blks = (DN_USED_BYTES(dn->dn_phys) +
1114 SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT;
1115 doi->doi_max_block_offset = dn->dn_phys->dn_maxblkid;
1116 doi->doi_type = dn->dn_type;
1117 doi->doi_bonus_size = dn->dn_bonuslen;
1118 doi->doi_bonus_type = dn->dn_bonustype;
1120 mutex_exit(&dn->dn_mtx);
1121 rw_exit(&dn->dn_struct_rwlock);
1125 * Get information on a DMU object.
1126 * If doi is NULL, just indicates whether the object exists.
1129 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1131 dnode_t *dn;
1132 int err = dnode_hold(os->os, object, FTAG, &dn);
1134 if (err)
1135 return (err);
1137 if (doi != NULL)
1138 dmu_object_info_from_dnode(dn, doi);
1140 dnode_rele(dn, FTAG);
1141 return (0);
1145 * As above, but faster; can be used when you have a held dbuf in hand.
1147 void
1148 dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi)
1150 dmu_object_info_from_dnode(((dmu_buf_impl_t *)db)->db_dnode, doi);
1154 * Faster still when you only care about the size.
1155 * This is specifically optimized for zfs_getattr().
1157 void
1158 dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize, u_longlong_t *nblk512)
1160 dnode_t *dn = ((dmu_buf_impl_t *)db)->db_dnode;
1162 *blksize = dn->dn_datablksz;
1163 /* add 1 for dnode space */
1164 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1165 SPA_MINBLOCKSHIFT) + 1;
1168 void
1169 byteswap_uint64_array(void *vbuf, size_t size)
1171 uint64_t *buf = vbuf;
1172 size_t count = size >> 3;
1173 int i;
1175 ASSERT((size & 7) == 0);
1177 for (i = 0; i < count; i++)
1178 buf[i] = BSWAP_64(buf[i]);
1181 void
1182 byteswap_uint32_array(void *vbuf, size_t size)
1184 uint32_t *buf = vbuf;
1185 size_t count = size >> 2;
1186 int i;
1188 ASSERT((size & 3) == 0);
1190 for (i = 0; i < count; i++)
1191 buf[i] = BSWAP_32(buf[i]);
1194 void
1195 byteswap_uint16_array(void *vbuf, size_t size)
1197 uint16_t *buf = vbuf;
1198 size_t count = size >> 1;
1199 int i;
1201 ASSERT((size & 1) == 0);
1203 for (i = 0; i < count; i++)
1204 buf[i] = BSWAP_16(buf[i]);
1207 /* ARGSUSED */
1208 void
1209 byteswap_uint8_array(void *vbuf, size_t size)
1213 void
1214 dmu_init(void)
1216 dbuf_init();
1217 dnode_init();
1218 arc_init();
1219 l2arc_init();
1222 void
1223 dmu_fini(void)
1225 arc_fini();
1226 dnode_fini();
1227 dbuf_fini();
1228 l2arc_fini();