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]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2013 by Delphix. All rights reserved.
25 /* Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */
26 /* Copyright (c) 2013, Joyent, Inc. All rights reserved. */
29 #include <sys/dmu_impl.h>
30 #include <sys/dmu_tx.h>
32 #include <sys/dnode.h>
33 #include <sys/zfs_context.h>
34 #include <sys/dmu_objset.h>
35 #include <sys/dmu_traverse.h>
36 #include <sys/dsl_dataset.h>
37 #include <sys/dsl_dir.h>
38 #include <sys/dsl_pool.h>
39 #include <sys/dsl_synctask.h>
40 #include <sys/dsl_prop.h>
41 #include <sys/dmu_zfetch.h>
42 #include <sys/zfs_ioctl.h>
44 #include <sys/zio_checksum.h>
45 #include <sys/zio_compress.h>
49 #include <sys/zfs_znode.h>
53 * Enable/disable nopwrite feature.
55 int zfs_nopwrite_enabled = 1;
56 SYSCTL_DECL(_vfs_zfs);
57 TUNABLE_INT("vfs.zfs.nopwrite_enabled", &zfs_nopwrite_enabled);
58 SYSCTL_INT(_vfs_zfs, OID_AUTO, nopwrite_enabled, CTLFLAG_RDTUN,
59 &zfs_nopwrite_enabled, 0, "Enable nopwrite feature");
61 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
62 { DMU_BSWAP_UINT8, TRUE, "unallocated" },
63 { DMU_BSWAP_ZAP, TRUE, "object directory" },
64 { DMU_BSWAP_UINT64, TRUE, "object array" },
65 { DMU_BSWAP_UINT8, TRUE, "packed nvlist" },
66 { DMU_BSWAP_UINT64, TRUE, "packed nvlist size" },
67 { DMU_BSWAP_UINT64, TRUE, "bpobj" },
68 { DMU_BSWAP_UINT64, TRUE, "bpobj header" },
69 { DMU_BSWAP_UINT64, TRUE, "SPA space map header" },
70 { DMU_BSWAP_UINT64, TRUE, "SPA space map" },
71 { DMU_BSWAP_UINT64, TRUE, "ZIL intent log" },
72 { DMU_BSWAP_DNODE, TRUE, "DMU dnode" },
73 { DMU_BSWAP_OBJSET, TRUE, "DMU objset" },
74 { DMU_BSWAP_UINT64, TRUE, "DSL directory" },
75 { DMU_BSWAP_ZAP, TRUE, "DSL directory child map"},
76 { DMU_BSWAP_ZAP, TRUE, "DSL dataset snap map" },
77 { DMU_BSWAP_ZAP, TRUE, "DSL props" },
78 { DMU_BSWAP_UINT64, TRUE, "DSL dataset" },
79 { DMU_BSWAP_ZNODE, TRUE, "ZFS znode" },
80 { DMU_BSWAP_OLDACL, TRUE, "ZFS V0 ACL" },
81 { DMU_BSWAP_UINT8, FALSE, "ZFS plain file" },
82 { DMU_BSWAP_ZAP, TRUE, "ZFS directory" },
83 { DMU_BSWAP_ZAP, TRUE, "ZFS master node" },
84 { DMU_BSWAP_ZAP, TRUE, "ZFS delete queue" },
85 { DMU_BSWAP_UINT8, FALSE, "zvol object" },
86 { DMU_BSWAP_ZAP, TRUE, "zvol prop" },
87 { DMU_BSWAP_UINT8, FALSE, "other uint8[]" },
88 { DMU_BSWAP_UINT64, FALSE, "other uint64[]" },
89 { DMU_BSWAP_ZAP, TRUE, "other ZAP" },
90 { DMU_BSWAP_ZAP, TRUE, "persistent error log" },
91 { DMU_BSWAP_UINT8, TRUE, "SPA history" },
92 { DMU_BSWAP_UINT64, TRUE, "SPA history offsets" },
93 { DMU_BSWAP_ZAP, TRUE, "Pool properties" },
94 { DMU_BSWAP_ZAP, TRUE, "DSL permissions" },
95 { DMU_BSWAP_ACL, TRUE, "ZFS ACL" },
96 { DMU_BSWAP_UINT8, TRUE, "ZFS SYSACL" },
97 { DMU_BSWAP_UINT8, TRUE, "FUID table" },
98 { DMU_BSWAP_UINT64, TRUE, "FUID table size" },
99 { DMU_BSWAP_ZAP, TRUE, "DSL dataset next clones"},
100 { DMU_BSWAP_ZAP, TRUE, "scan work queue" },
101 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group used" },
102 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group quota" },
103 { DMU_BSWAP_ZAP, TRUE, "snapshot refcount tags"},
104 { DMU_BSWAP_ZAP, TRUE, "DDT ZAP algorithm" },
105 { DMU_BSWAP_ZAP, TRUE, "DDT statistics" },
106 { DMU_BSWAP_UINT8, TRUE, "System attributes" },
107 { DMU_BSWAP_ZAP, TRUE, "SA master node" },
108 { DMU_BSWAP_ZAP, TRUE, "SA attr registration" },
109 { DMU_BSWAP_ZAP, TRUE, "SA attr layouts" },
110 { DMU_BSWAP_ZAP, TRUE, "scan translations" },
111 { DMU_BSWAP_UINT8, FALSE, "deduplicated block" },
112 { DMU_BSWAP_ZAP, TRUE, "DSL deadlist map" },
113 { DMU_BSWAP_UINT64, TRUE, "DSL deadlist map hdr" },
114 { DMU_BSWAP_ZAP, TRUE, "DSL dir clones" },
115 { DMU_BSWAP_UINT64, TRUE, "bpobj subobj" }
118 const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = {
119 { byteswap_uint8_array, "uint8" },
120 { byteswap_uint16_array, "uint16" },
121 { byteswap_uint32_array, "uint32" },
122 { byteswap_uint64_array, "uint64" },
123 { zap_byteswap, "zap" },
124 { dnode_buf_byteswap, "dnode" },
125 { dmu_objset_byteswap, "objset" },
126 { zfs_znode_byteswap, "znode" },
127 { zfs_oldacl_byteswap, "oldacl" },
128 { zfs_acl_byteswap, "acl" }
132 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
133 void *tag, dmu_buf_t **dbp, int flags)
139 int db_flags = DB_RF_CANFAIL;
141 if (flags & DMU_READ_NO_PREFETCH)
142 db_flags |= DB_RF_NOPREFETCH;
144 err = dnode_hold(os, object, FTAG, &dn);
147 blkid = dbuf_whichblock(dn, offset);
148 rw_enter(&dn->dn_struct_rwlock, RW_READER);
149 db = dbuf_hold(dn, blkid, tag);
150 rw_exit(&dn->dn_struct_rwlock);
152 err = SET_ERROR(EIO);
154 err = dbuf_read(db, NULL, db_flags);
161 dnode_rele(dn, FTAG);
162 *dbp = &db->db; /* NULL db plus first field offset is NULL */
169 return (DN_MAX_BONUSLEN);
173 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx)
175 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
182 if (dn->dn_bonus != db) {
183 error = SET_ERROR(EINVAL);
184 } else if (newsize < 0 || newsize > db_fake->db_size) {
185 error = SET_ERROR(EINVAL);
187 dnode_setbonuslen(dn, newsize, tx);
196 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx)
198 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
205 if (!DMU_OT_IS_VALID(type)) {
206 error = SET_ERROR(EINVAL);
207 } else if (dn->dn_bonus != db) {
208 error = SET_ERROR(EINVAL);
210 dnode_setbonus_type(dn, type, tx);
219 dmu_get_bonustype(dmu_buf_t *db_fake)
221 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
223 dmu_object_type_t type;
227 type = dn->dn_bonustype;
234 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx)
239 error = dnode_hold(os, object, FTAG, &dn);
240 dbuf_rm_spill(dn, tx);
241 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
242 dnode_rm_spill(dn, tx);
243 rw_exit(&dn->dn_struct_rwlock);
244 dnode_rele(dn, FTAG);
249 * returns ENOENT, EIO, or 0.
252 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
258 error = dnode_hold(os, object, FTAG, &dn);
262 rw_enter(&dn->dn_struct_rwlock, RW_READER);
263 if (dn->dn_bonus == NULL) {
264 rw_exit(&dn->dn_struct_rwlock);
265 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
266 if (dn->dn_bonus == NULL)
267 dbuf_create_bonus(dn);
271 /* as long as the bonus buf is held, the dnode will be held */
272 if (refcount_add(&db->db_holds, tag) == 1) {
273 VERIFY(dnode_add_ref(dn, db));
274 (void) atomic_inc_32_nv(&dn->dn_dbufs_count);
278 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's
279 * hold and incrementing the dbuf count to ensure that dnode_move() sees
280 * a dnode hold for every dbuf.
282 rw_exit(&dn->dn_struct_rwlock);
284 dnode_rele(dn, FTAG);
286 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH));
293 * returns ENOENT, EIO, or 0.
295 * This interface will allocate a blank spill dbuf when a spill blk
296 * doesn't already exist on the dnode.
298 * if you only want to find an already existing spill db, then
299 * dmu_spill_hold_existing() should be used.
302 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp)
304 dmu_buf_impl_t *db = NULL;
307 if ((flags & DB_RF_HAVESTRUCT) == 0)
308 rw_enter(&dn->dn_struct_rwlock, RW_READER);
310 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag);
312 if ((flags & DB_RF_HAVESTRUCT) == 0)
313 rw_exit(&dn->dn_struct_rwlock);
316 err = dbuf_read(db, NULL, flags);
325 dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
327 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
334 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) {
335 err = SET_ERROR(EINVAL);
337 rw_enter(&dn->dn_struct_rwlock, RW_READER);
339 if (!dn->dn_have_spill) {
340 err = SET_ERROR(ENOENT);
342 err = dmu_spill_hold_by_dnode(dn,
343 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp);
346 rw_exit(&dn->dn_struct_rwlock);
354 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
356 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
362 err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp);
369 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
370 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
371 * and can induce severe lock contention when writing to several files
372 * whose dnodes are in the same block.
375 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
376 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
379 uint64_t blkid, nblks, i;
384 ASSERT(length <= DMU_MAX_ACCESS);
386 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
387 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
388 dbuf_flags |= DB_RF_NOPREFETCH;
390 rw_enter(&dn->dn_struct_rwlock, RW_READER);
391 if (dn->dn_datablkshift) {
392 int blkshift = dn->dn_datablkshift;
393 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
394 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
396 if (offset + length > dn->dn_datablksz) {
397 zfs_panic_recover("zfs: accessing past end of object "
398 "%llx/%llx (size=%u access=%llu+%llu)",
399 (longlong_t)dn->dn_objset->
400 os_dsl_dataset->ds_object,
401 (longlong_t)dn->dn_object, dn->dn_datablksz,
402 (longlong_t)offset, (longlong_t)length);
403 rw_exit(&dn->dn_struct_rwlock);
404 return (SET_ERROR(EIO));
408 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
410 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
411 blkid = dbuf_whichblock(dn, offset);
412 for (i = 0; i < nblks; i++) {
413 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
415 rw_exit(&dn->dn_struct_rwlock);
416 dmu_buf_rele_array(dbp, nblks, tag);
418 return (SET_ERROR(EIO));
420 /* initiate async i/o */
422 (void) dbuf_read(db, zio, dbuf_flags);
425 curthread->td_ru.ru_oublock++;
429 rw_exit(&dn->dn_struct_rwlock);
431 /* wait for async i/o */
434 dmu_buf_rele_array(dbp, nblks, tag);
438 /* wait for other io to complete */
440 for (i = 0; i < nblks; i++) {
441 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
442 mutex_enter(&db->db_mtx);
443 while (db->db_state == DB_READ ||
444 db->db_state == DB_FILL)
445 cv_wait(&db->db_changed, &db->db_mtx);
446 if (db->db_state == DB_UNCACHED)
447 err = SET_ERROR(EIO);
448 mutex_exit(&db->db_mtx);
450 dmu_buf_rele_array(dbp, nblks, tag);
462 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
463 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
468 err = dnode_hold(os, object, FTAG, &dn);
472 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
473 numbufsp, dbpp, DMU_READ_PREFETCH);
475 dnode_rele(dn, FTAG);
481 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset,
482 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
484 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
490 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
491 numbufsp, dbpp, DMU_READ_PREFETCH);
498 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
501 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
506 for (i = 0; i < numbufs; i++) {
508 dbuf_rele(dbp[i], tag);
511 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
515 * Issue prefetch i/os for the given blocks.
517 * Note: The assumption is that we *know* these blocks will be needed
518 * almost immediately. Therefore, the prefetch i/os will be issued at
519 * ZIO_PRIORITY_SYNC_READ
521 * Note: indirect blocks and other metadata will be read synchronously,
522 * causing this function to block if they are not already cached.
525 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
531 if (zfs_prefetch_disable)
534 if (len == 0) { /* they're interested in the bonus buffer */
535 dn = DMU_META_DNODE(os);
537 if (object == 0 || object >= DN_MAX_OBJECT)
540 rw_enter(&dn->dn_struct_rwlock, RW_READER);
541 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
542 dbuf_prefetch(dn, blkid, ZIO_PRIORITY_SYNC_READ);
543 rw_exit(&dn->dn_struct_rwlock);
548 * XXX - Note, if the dnode for the requested object is not
549 * already cached, we will do a *synchronous* read in the
550 * dnode_hold() call. The same is true for any indirects.
552 err = dnode_hold(os, object, FTAG, &dn);
556 rw_enter(&dn->dn_struct_rwlock, RW_READER);
557 if (dn->dn_datablkshift) {
558 int blkshift = dn->dn_datablkshift;
559 nblks = (P2ROUNDUP(offset + len, 1 << blkshift) -
560 P2ALIGN(offset, 1 << blkshift)) >> blkshift;
562 nblks = (offset < dn->dn_datablksz);
566 blkid = dbuf_whichblock(dn, offset);
567 for (int i = 0; i < nblks; i++)
568 dbuf_prefetch(dn, blkid + i, ZIO_PRIORITY_SYNC_READ);
571 rw_exit(&dn->dn_struct_rwlock);
573 dnode_rele(dn, FTAG);
577 * Get the next "chunk" of file data to free. We traverse the file from
578 * the end so that the file gets shorter over time (if we crashes in the
579 * middle, this will leave us in a better state). We find allocated file
580 * data by simply searching the allocated level 1 indirects.
582 * On input, *start should be the first offset that does not need to be
583 * freed (e.g. "offset + length"). On return, *start will be the first
584 * offset that should be freed.
587 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum)
589 uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1);
590 /* bytes of data covered by a level-1 indirect block */
592 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
594 ASSERT3U(minimum, <=, *start);
596 if (*start - minimum <= iblkrange * maxblks) {
600 ASSERT(ISP2(iblkrange));
602 for (uint64_t blks = 0; *start > minimum && blks < maxblks; blks++) {
606 * dnode_next_offset(BACKWARDS) will find an allocated L1
607 * indirect block at or before the input offset. We must
608 * decrement *start so that it is at the end of the region
612 err = dnode_next_offset(dn,
613 DNODE_FIND_BACKWARDS, start, 2, 1, 0);
615 /* if there are no indirect blocks before start, we are done */
619 } else if (err != 0) {
623 /* set start to the beginning of this L1 indirect */
624 *start = P2ALIGN(*start, iblkrange);
626 if (*start < minimum)
632 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
635 uint64_t object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz;
638 if (offset >= object_size)
641 if (length == DMU_OBJECT_END || offset + length > object_size)
642 length = object_size - offset;
644 while (length != 0) {
645 uint64_t chunk_end, chunk_begin;
647 chunk_end = chunk_begin = offset + length;
649 /* move chunk_begin backwards to the beginning of this chunk */
650 err = get_next_chunk(dn, &chunk_begin, offset);
653 ASSERT3U(chunk_begin, >=, offset);
654 ASSERT3U(chunk_begin, <=, chunk_end);
656 dmu_tx_t *tx = dmu_tx_create(os);
657 dmu_tx_hold_free(tx, dn->dn_object,
658 chunk_begin, chunk_end - chunk_begin);
659 err = dmu_tx_assign(tx, TXG_WAIT);
664 dnode_free_range(dn, chunk_begin, chunk_end - chunk_begin, tx);
667 length -= chunk_end - chunk_begin;
673 dmu_free_long_range(objset_t *os, uint64_t object,
674 uint64_t offset, uint64_t length)
679 err = dnode_hold(os, object, FTAG, &dn);
682 err = dmu_free_long_range_impl(os, dn, offset, length);
685 * It is important to zero out the maxblkid when freeing the entire
686 * file, so that (a) subsequent calls to dmu_free_long_range_impl()
687 * will take the fast path, and (b) dnode_reallocate() can verify
688 * that the entire file has been freed.
690 if (err == 0 && offset == 0 && length == DMU_OBJECT_END)
693 dnode_rele(dn, FTAG);
698 dmu_free_long_object(objset_t *os, uint64_t object)
703 err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END);
707 tx = dmu_tx_create(os);
708 dmu_tx_hold_bonus(tx, object);
709 dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END);
710 err = dmu_tx_assign(tx, TXG_WAIT);
712 err = dmu_object_free(os, object, tx);
722 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
723 uint64_t size, dmu_tx_t *tx)
726 int err = dnode_hold(os, object, FTAG, &dn);
729 ASSERT(offset < UINT64_MAX);
730 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
731 dnode_free_range(dn, offset, size, tx);
732 dnode_rele(dn, FTAG);
737 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
738 void *buf, uint32_t flags)
744 err = dnode_hold(os, object, FTAG, &dn);
749 * Deal with odd block sizes, where there can't be data past the first
750 * block. If we ever do the tail block optimization, we will need to
751 * handle that here as well.
753 if (dn->dn_maxblkid == 0) {
754 int newsz = offset > dn->dn_datablksz ? 0 :
755 MIN(size, dn->dn_datablksz - offset);
756 bzero((char *)buf + newsz, size - newsz);
761 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
765 * NB: we could do this block-at-a-time, but it's nice
766 * to be reading in parallel.
768 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
769 TRUE, FTAG, &numbufs, &dbp, flags);
773 for (i = 0; i < numbufs; i++) {
776 dmu_buf_t *db = dbp[i];
780 bufoff = offset - db->db_offset;
781 tocpy = (int)MIN(db->db_size - bufoff, size);
783 bcopy((char *)db->db_data + bufoff, buf, tocpy);
787 buf = (char *)buf + tocpy;
789 dmu_buf_rele_array(dbp, numbufs, FTAG);
791 dnode_rele(dn, FTAG);
796 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
797 const void *buf, dmu_tx_t *tx)
805 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
806 FALSE, FTAG, &numbufs, &dbp));
808 for (i = 0; i < numbufs; i++) {
811 dmu_buf_t *db = dbp[i];
815 bufoff = offset - db->db_offset;
816 tocpy = (int)MIN(db->db_size - bufoff, size);
818 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
820 if (tocpy == db->db_size)
821 dmu_buf_will_fill(db, tx);
823 dmu_buf_will_dirty(db, tx);
825 bcopy(buf, (char *)db->db_data + bufoff, tocpy);
827 if (tocpy == db->db_size)
828 dmu_buf_fill_done(db, tx);
832 buf = (char *)buf + tocpy;
834 dmu_buf_rele_array(dbp, numbufs, FTAG);
838 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
847 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
848 FALSE, FTAG, &numbufs, &dbp));
850 for (i = 0; i < numbufs; i++) {
851 dmu_buf_t *db = dbp[i];
853 dmu_buf_will_not_fill(db, tx);
855 dmu_buf_rele_array(dbp, numbufs, FTAG);
859 * DMU support for xuio
861 kstat_t *xuio_ksp = NULL;
864 dmu_xuio_init(xuio_t *xuio, int nblk)
867 uio_t *uio = &xuio->xu_uio;
869 uio->uio_iovcnt = nblk;
870 uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_SLEEP);
872 priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP);
874 priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP);
875 priv->iovp = uio->uio_iov;
876 XUIO_XUZC_PRIV(xuio) = priv;
878 if (XUIO_XUZC_RW(xuio) == UIO_READ)
879 XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk);
881 XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk);
887 dmu_xuio_fini(xuio_t *xuio)
889 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
890 int nblk = priv->cnt;
892 kmem_free(priv->iovp, nblk * sizeof (iovec_t));
893 kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *));
894 kmem_free(priv, sizeof (dmu_xuio_t));
896 if (XUIO_XUZC_RW(xuio) == UIO_READ)
897 XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk);
899 XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk);
903 * Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf }
904 * and increase priv->next by 1.
907 dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n)
910 uio_t *uio = &xuio->xu_uio;
911 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
912 int i = priv->next++;
914 ASSERT(i < priv->cnt);
915 ASSERT(off + n <= arc_buf_size(abuf));
916 iov = uio->uio_iov + i;
917 iov->iov_base = (char *)abuf->b_data + off;
919 priv->bufs[i] = abuf;
924 dmu_xuio_cnt(xuio_t *xuio)
926 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
931 dmu_xuio_arcbuf(xuio_t *xuio, int i)
933 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
935 ASSERT(i < priv->cnt);
936 return (priv->bufs[i]);
940 dmu_xuio_clear(xuio_t *xuio, int i)
942 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
944 ASSERT(i < priv->cnt);
945 priv->bufs[i] = NULL;
951 xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc",
952 KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t),
954 if (xuio_ksp != NULL) {
955 xuio_ksp->ks_data = &xuio_stats;
956 kstat_install(xuio_ksp);
963 if (xuio_ksp != NULL) {
964 kstat_delete(xuio_ksp);
970 xuio_stat_wbuf_copied()
972 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
976 xuio_stat_wbuf_nocopy()
978 XUIOSTAT_BUMP(xuiostat_wbuf_nocopy);
983 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
990 * NB: we could do this block-at-a-time, but it's nice
991 * to be reading in parallel.
993 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
999 if (uio->uio_extflg == UIO_XUIO)
1000 xuio = (xuio_t *)uio;
1003 for (i = 0; i < numbufs; i++) {
1006 dmu_buf_t *db = dbp[i];
1010 bufoff = uio->uio_loffset - db->db_offset;
1011 tocpy = (int)MIN(db->db_size - bufoff, size);
1014 dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db;
1015 arc_buf_t *dbuf_abuf = dbi->db_buf;
1016 arc_buf_t *abuf = dbuf_loan_arcbuf(dbi);
1017 err = dmu_xuio_add(xuio, abuf, bufoff, tocpy);
1019 uio->uio_resid -= tocpy;
1020 uio->uio_loffset += tocpy;
1023 if (abuf == dbuf_abuf)
1024 XUIOSTAT_BUMP(xuiostat_rbuf_nocopy);
1026 XUIOSTAT_BUMP(xuiostat_rbuf_copied);
1028 err = uiomove((char *)db->db_data + bufoff, tocpy,
1036 dmu_buf_rele_array(dbp, numbufs, FTAG);
1042 dmu_write_uio_dnode(dnode_t *dn, uio_t *uio, uint64_t size, dmu_tx_t *tx)
1049 err = dmu_buf_hold_array_by_dnode(dn, uio->uio_loffset, size,
1050 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH);
1054 for (i = 0; i < numbufs; i++) {
1057 dmu_buf_t *db = dbp[i];
1061 bufoff = uio->uio_loffset - db->db_offset;
1062 tocpy = (int)MIN(db->db_size - bufoff, size);
1064 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1066 if (tocpy == db->db_size)
1067 dmu_buf_will_fill(db, tx);
1069 dmu_buf_will_dirty(db, tx);
1072 * XXX uiomove could block forever (eg. nfs-backed
1073 * pages). There needs to be a uiolockdown() function
1074 * to lock the pages in memory, so that uiomove won't
1077 err = uiomove((char *)db->db_data + bufoff, tocpy,
1080 if (tocpy == db->db_size)
1081 dmu_buf_fill_done(db, tx);
1089 dmu_buf_rele_array(dbp, numbufs, FTAG);
1094 dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size,
1097 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
1106 err = dmu_write_uio_dnode(dn, uio, size, tx);
1113 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
1122 err = dnode_hold(os, object, FTAG, &dn);
1126 err = dmu_write_uio_dnode(dn, uio, size, tx);
1128 dnode_rele(dn, FTAG);
1135 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1136 page_t *pp, dmu_tx_t *tx)
1145 err = dmu_buf_hold_array(os, object, offset, size,
1146 FALSE, FTAG, &numbufs, &dbp);
1150 for (i = 0; i < numbufs; i++) {
1151 int tocpy, copied, thiscpy;
1153 dmu_buf_t *db = dbp[i];
1157 ASSERT3U(db->db_size, >=, PAGESIZE);
1159 bufoff = offset - db->db_offset;
1160 tocpy = (int)MIN(db->db_size - bufoff, size);
1162 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1164 if (tocpy == db->db_size)
1165 dmu_buf_will_fill(db, tx);
1167 dmu_buf_will_dirty(db, tx);
1169 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
1170 ASSERT3U(pp->p_offset, ==, db->db_offset + bufoff);
1171 thiscpy = MIN(PAGESIZE, tocpy - copied);
1172 va = zfs_map_page(pp, S_READ);
1173 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
1174 zfs_unmap_page(pp, va);
1179 if (tocpy == db->db_size)
1180 dmu_buf_fill_done(db, tx);
1185 dmu_buf_rele_array(dbp, numbufs, FTAG);
1192 dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
1193 vm_page_t *ma, dmu_tx_t *tx)
1203 err = dmu_buf_hold_array(os, object, offset, size,
1204 FALSE, FTAG, &numbufs, &dbp);
1208 for (i = 0; i < numbufs; i++) {
1209 int tocpy, copied, thiscpy;
1211 dmu_buf_t *db = dbp[i];
1215 ASSERT3U(db->db_size, >=, PAGESIZE);
1217 bufoff = offset - db->db_offset;
1218 tocpy = (int)MIN(db->db_size - bufoff, size);
1220 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1222 if (tocpy == db->db_size)
1223 dmu_buf_will_fill(db, tx);
1225 dmu_buf_will_dirty(db, tx);
1227 for (copied = 0; copied < tocpy; copied += PAGESIZE) {
1228 ASSERT3U(ptoa((*ma)->pindex), ==, db->db_offset + bufoff);
1229 thiscpy = MIN(PAGESIZE, tocpy - copied);
1230 va = zfs_map_page(*ma, &sf);
1231 bcopy(va, (char *)db->db_data + bufoff, thiscpy);
1237 if (tocpy == db->db_size)
1238 dmu_buf_fill_done(db, tx);
1243 dmu_buf_rele_array(dbp, numbufs, FTAG);
1250 * Allocate a loaned anonymous arc buffer.
1253 dmu_request_arcbuf(dmu_buf_t *handle, int size)
1255 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
1257 return (arc_loan_buf(db->db_objset->os_spa, size));
1261 * Free a loaned arc buffer.
1264 dmu_return_arcbuf(arc_buf_t *buf)
1266 arc_return_buf(buf, FTAG);
1267 VERIFY(arc_buf_remove_ref(buf, FTAG));
1271 * When possible directly assign passed loaned arc buffer to a dbuf.
1272 * If this is not possible copy the contents of passed arc buf via
1276 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
1279 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle;
1282 uint32_t blksz = (uint32_t)arc_buf_size(buf);
1285 DB_DNODE_ENTER(dbuf);
1286 dn = DB_DNODE(dbuf);
1287 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1288 blkid = dbuf_whichblock(dn, offset);
1289 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
1290 rw_exit(&dn->dn_struct_rwlock);
1291 DB_DNODE_EXIT(dbuf);
1293 if (offset == db->db.db_offset && blksz == db->db.db_size) {
1294 dbuf_assign_arcbuf(db, buf, tx);
1295 dbuf_rele(db, FTAG);
1300 DB_DNODE_ENTER(dbuf);
1301 dn = DB_DNODE(dbuf);
1303 object = dn->dn_object;
1304 DB_DNODE_EXIT(dbuf);
1306 dbuf_rele(db, FTAG);
1307 dmu_write(os, object, offset, blksz, buf->b_data, tx);
1308 dmu_return_arcbuf(buf);
1309 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
1314 dbuf_dirty_record_t *dsa_dr;
1315 dmu_sync_cb_t *dsa_done;
1322 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
1324 dmu_sync_arg_t *dsa = varg;
1325 dmu_buf_t *db = dsa->dsa_zgd->zgd_db;
1326 blkptr_t *bp = zio->io_bp;
1328 if (zio->io_error == 0) {
1329 if (BP_IS_HOLE(bp)) {
1331 * A block of zeros may compress to a hole, but the
1332 * block size still needs to be known for replay.
1334 BP_SET_LSIZE(bp, db->db_size);
1336 ASSERT(BP_GET_LEVEL(bp) == 0);
1343 dmu_sync_late_arrival_ready(zio_t *zio)
1345 dmu_sync_ready(zio, NULL, zio->io_private);
1350 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
1352 dmu_sync_arg_t *dsa = varg;
1353 dbuf_dirty_record_t *dr = dsa->dsa_dr;
1354 dmu_buf_impl_t *db = dr->dr_dbuf;
1356 mutex_enter(&db->db_mtx);
1357 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
1358 if (zio->io_error == 0) {
1359 dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE);
1360 if (dr->dt.dl.dr_nopwrite) {
1361 blkptr_t *bp = zio->io_bp;
1362 blkptr_t *bp_orig = &zio->io_bp_orig;
1363 uint8_t chksum = BP_GET_CHECKSUM(bp_orig);
1365 ASSERT(BP_EQUAL(bp, bp_orig));
1366 ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF);
1367 ASSERT(zio_checksum_table[chksum].ci_dedup);
1369 dr->dt.dl.dr_overridden_by = *zio->io_bp;
1370 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
1371 dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
1372 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by))
1373 BP_ZERO(&dr->dt.dl.dr_overridden_by);
1375 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
1377 cv_broadcast(&db->db_changed);
1378 mutex_exit(&db->db_mtx);
1380 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1382 kmem_free(dsa, sizeof (*dsa));
1386 dmu_sync_late_arrival_done(zio_t *zio)
1388 blkptr_t *bp = zio->io_bp;
1389 dmu_sync_arg_t *dsa = zio->io_private;
1390 blkptr_t *bp_orig = &zio->io_bp_orig;
1392 if (zio->io_error == 0 && !BP_IS_HOLE(bp)) {
1394 * If we didn't allocate a new block (i.e. ZIO_FLAG_NOPWRITE)
1395 * then there is nothing to do here. Otherwise, free the
1396 * newly allocated block in this txg.
1398 if (zio->io_flags & ZIO_FLAG_NOPWRITE) {
1399 ASSERT(BP_EQUAL(bp, bp_orig));
1401 ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig));
1402 ASSERT(zio->io_bp->blk_birth == zio->io_txg);
1403 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa));
1404 zio_free(zio->io_spa, zio->io_txg, zio->io_bp);
1408 dmu_tx_commit(dsa->dsa_tx);
1410 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1412 kmem_free(dsa, sizeof (*dsa));
1416 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd,
1417 zio_prop_t *zp, zbookmark_t *zb)
1419 dmu_sync_arg_t *dsa;
1422 tx = dmu_tx_create(os);
1423 dmu_tx_hold_space(tx, zgd->zgd_db->db_size);
1424 if (dmu_tx_assign(tx, TXG_WAIT) != 0) {
1426 /* Make zl_get_data do txg_waited_synced() */
1427 return (SET_ERROR(EIO));
1430 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1432 dsa->dsa_done = done;
1436 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp,
1437 zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp,
1438 dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, dsa,
1439 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb));
1445 * Intent log support: sync the block associated with db to disk.
1446 * N.B. and XXX: the caller is responsible for making sure that the
1447 * data isn't changing while dmu_sync() is writing it.
1451 * EEXIST: this txg has already been synced, so there's nothing to do.
1452 * The caller should not log the write.
1454 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
1455 * The caller should not log the write.
1457 * EALREADY: this block is already in the process of being synced.
1458 * The caller should track its progress (somehow).
1460 * EIO: could not do the I/O.
1461 * The caller should do a txg_wait_synced().
1463 * 0: the I/O has been initiated.
1464 * The caller should log this blkptr in the done callback.
1465 * It is possible that the I/O will fail, in which case
1466 * the error will be reported to the done callback and
1467 * propagated to pio from zio_done().
1470 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd)
1472 blkptr_t *bp = zgd->zgd_bp;
1473 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db;
1474 objset_t *os = db->db_objset;
1475 dsl_dataset_t *ds = os->os_dsl_dataset;
1476 dbuf_dirty_record_t *dr;
1477 dmu_sync_arg_t *dsa;
1482 ASSERT(pio != NULL);
1485 SET_BOOKMARK(&zb, ds->ds_object,
1486 db->db.db_object, db->db_level, db->db_blkid);
1490 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp);
1494 * If we're frozen (running ziltest), we always need to generate a bp.
1496 if (txg > spa_freeze_txg(os->os_spa))
1497 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1500 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf()
1501 * and us. If we determine that this txg is not yet syncing,
1502 * but it begins to sync a moment later, that's OK because the
1503 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx.
1505 mutex_enter(&db->db_mtx);
1507 if (txg <= spa_last_synced_txg(os->os_spa)) {
1509 * This txg has already synced. There's nothing to do.
1511 mutex_exit(&db->db_mtx);
1512 return (SET_ERROR(EEXIST));
1515 if (txg <= spa_syncing_txg(os->os_spa)) {
1517 * This txg is currently syncing, so we can't mess with
1518 * the dirty record anymore; just write a new log block.
1520 mutex_exit(&db->db_mtx);
1521 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1524 dr = db->db_last_dirty;
1525 while (dr && dr->dr_txg != txg)
1530 * There's no dr for this dbuf, so it must have been freed.
1531 * There's no need to log writes to freed blocks, so we're done.
1533 mutex_exit(&db->db_mtx);
1534 return (SET_ERROR(ENOENT));
1537 ASSERT(dr->dr_next == NULL || dr->dr_next->dr_txg < txg);
1540 * Assume the on-disk data is X, the current syncing data is Y,
1541 * and the current in-memory data is Z (currently in dmu_sync).
1542 * X and Z are identical but Y is has been modified. Normally,
1543 * when X and Z are the same we will perform a nopwrite but if Y
1544 * is different we must disable nopwrite since the resulting write
1545 * of Y to disk can free the block containing X. If we allowed a
1546 * nopwrite to occur the block pointing to Z would reference a freed
1547 * block. Since this is a rare case we simplify this by disabling
1548 * nopwrite if the current dmu_sync-ing dbuf has been modified in
1549 * a previous transaction.
1552 zp.zp_nopwrite = B_FALSE;
1554 ASSERT(dr->dr_txg == txg);
1555 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC ||
1556 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
1558 * We have already issued a sync write for this buffer,
1559 * or this buffer has already been synced. It could not
1560 * have been dirtied since, or we would have cleared the state.
1562 mutex_exit(&db->db_mtx);
1563 return (SET_ERROR(EALREADY));
1566 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN);
1567 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
1568 mutex_exit(&db->db_mtx);
1570 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
1572 dsa->dsa_done = done;
1576 zio_nowait(arc_write(pio, os->os_spa, txg,
1577 bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db),
1578 DBUF_IS_L2COMPRESSIBLE(db), &zp, dmu_sync_ready,
1579 NULL, dmu_sync_done, dsa, ZIO_PRIORITY_SYNC_WRITE,
1580 ZIO_FLAG_CANFAIL, &zb));
1586 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1592 err = dnode_hold(os, object, FTAG, &dn);
1595 err = dnode_set_blksz(dn, size, ibs, tx);
1596 dnode_rele(dn, FTAG);
1601 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1606 /* XXX assumes dnode_hold will not get an i/o error */
1607 (void) dnode_hold(os, object, FTAG, &dn);
1608 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1609 dn->dn_checksum = checksum;
1610 dnode_setdirty(dn, tx);
1611 dnode_rele(dn, FTAG);
1615 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1620 /* XXX assumes dnode_hold will not get an i/o error */
1621 (void) dnode_hold(os, object, FTAG, &dn);
1622 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1623 dn->dn_compress = compress;
1624 dnode_setdirty(dn, tx);
1625 dnode_rele(dn, FTAG);
1628 int zfs_mdcomp_disable = 0;
1629 TUNABLE_INT("vfs.zfs.mdcomp_disable", &zfs_mdcomp_disable);
1630 SYSCTL_INT(_vfs_zfs, OID_AUTO, mdcomp_disable, CTLFLAG_RW,
1631 &zfs_mdcomp_disable, 0, "Disable metadata compression");
1634 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
1636 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET;
1637 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) ||
1639 enum zio_checksum checksum = os->os_checksum;
1640 enum zio_compress compress = os->os_compress;
1641 enum zio_checksum dedup_checksum = os->os_dedup_checksum;
1642 boolean_t dedup = B_FALSE;
1643 boolean_t nopwrite = B_FALSE;
1644 boolean_t dedup_verify = os->os_dedup_verify;
1645 int copies = os->os_copies;
1648 * We maintain different write policies for each of the following
1651 * 2. preallocated blocks (i.e. level-0 blocks of a dump device)
1652 * 3. all other level 0 blocks
1656 * XXX -- we should design a compression algorithm
1657 * that specializes in arrays of bps.
1659 compress = zfs_mdcomp_disable ? ZIO_COMPRESS_EMPTY :
1663 * Metadata always gets checksummed. If the data
1664 * checksum is multi-bit correctable, and it's not a
1665 * ZBT-style checksum, then it's suitable for metadata
1666 * as well. Otherwise, the metadata checksum defaults
1669 if (zio_checksum_table[checksum].ci_correctable < 1 ||
1670 zio_checksum_table[checksum].ci_eck)
1671 checksum = ZIO_CHECKSUM_FLETCHER_4;
1672 } else if (wp & WP_NOFILL) {
1676 * If we're writing preallocated blocks, we aren't actually
1677 * writing them so don't set any policy properties. These
1678 * blocks are currently only used by an external subsystem
1679 * outside of zfs (i.e. dump) and not written by the zio
1682 compress = ZIO_COMPRESS_OFF;
1683 checksum = ZIO_CHECKSUM_NOPARITY;
1685 compress = zio_compress_select(dn->dn_compress, compress);
1687 checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ?
1688 zio_checksum_select(dn->dn_checksum, checksum) :
1692 * Determine dedup setting. If we are in dmu_sync(),
1693 * we won't actually dedup now because that's all
1694 * done in syncing context; but we do want to use the
1695 * dedup checkum. If the checksum is not strong
1696 * enough to ensure unique signatures, force
1699 if (dedup_checksum != ZIO_CHECKSUM_OFF) {
1700 dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE;
1701 if (!zio_checksum_table[checksum].ci_dedup)
1702 dedup_verify = B_TRUE;
1706 * Enable nopwrite if we have a cryptographically secure
1707 * checksum that has no known collisions (i.e. SHA-256)
1708 * and compression is enabled. We don't enable nopwrite if
1709 * dedup is enabled as the two features are mutually exclusive.
1711 nopwrite = (!dedup && zio_checksum_table[checksum].ci_dedup &&
1712 compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled);
1715 zp->zp_checksum = checksum;
1716 zp->zp_compress = compress;
1717 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
1718 zp->zp_level = level;
1719 zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa));
1720 zp->zp_dedup = dedup;
1721 zp->zp_dedup_verify = dedup && dedup_verify;
1722 zp->zp_nopwrite = nopwrite;
1726 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1731 err = dnode_hold(os, object, FTAG, &dn);
1735 * Sync any current changes before
1736 * we go trundling through the block pointers.
1738 for (i = 0; i < TXG_SIZE; i++) {
1739 if (list_link_active(&dn->dn_dirty_link[i]))
1742 if (i != TXG_SIZE) {
1743 dnode_rele(dn, FTAG);
1744 txg_wait_synced(dmu_objset_pool(os), 0);
1745 err = dnode_hold(os, object, FTAG, &dn);
1750 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1751 dnode_rele(dn, FTAG);
1757 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1761 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1762 mutex_enter(&dn->dn_mtx);
1766 doi->doi_data_block_size = dn->dn_datablksz;
1767 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1768 1ULL << dn->dn_indblkshift : 0;
1769 doi->doi_type = dn->dn_type;
1770 doi->doi_bonus_type = dn->dn_bonustype;
1771 doi->doi_bonus_size = dn->dn_bonuslen;
1772 doi->doi_indirection = dn->dn_nlevels;
1773 doi->doi_checksum = dn->dn_checksum;
1774 doi->doi_compress = dn->dn_compress;
1775 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
1776 doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz;
1777 doi->doi_fill_count = 0;
1778 for (int i = 0; i < dnp->dn_nblkptr; i++)
1779 doi->doi_fill_count += dnp->dn_blkptr[i].blk_fill;
1781 mutex_exit(&dn->dn_mtx);
1782 rw_exit(&dn->dn_struct_rwlock);
1786 * Get information on a DMU object.
1787 * If doi is NULL, just indicates whether the object exists.
1790 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1793 int err = dnode_hold(os, object, FTAG, &dn);
1799 dmu_object_info_from_dnode(dn, doi);
1801 dnode_rele(dn, FTAG);
1806 * As above, but faster; can be used when you have a held dbuf in hand.
1809 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi)
1811 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1814 dmu_object_info_from_dnode(DB_DNODE(db), doi);
1819 * Faster still when you only care about the size.
1820 * This is specifically optimized for zfs_getattr().
1823 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize,
1824 u_longlong_t *nblk512)
1826 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1832 *blksize = dn->dn_datablksz;
1833 /* add 1 for dnode space */
1834 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1835 SPA_MINBLOCKSHIFT) + 1;
1840 byteswap_uint64_array(void *vbuf, size_t size)
1842 uint64_t *buf = vbuf;
1843 size_t count = size >> 3;
1846 ASSERT((size & 7) == 0);
1848 for (i = 0; i < count; i++)
1849 buf[i] = BSWAP_64(buf[i]);
1853 byteswap_uint32_array(void *vbuf, size_t size)
1855 uint32_t *buf = vbuf;
1856 size_t count = size >> 2;
1859 ASSERT((size & 3) == 0);
1861 for (i = 0; i < count; i++)
1862 buf[i] = BSWAP_32(buf[i]);
1866 byteswap_uint16_array(void *vbuf, size_t size)
1868 uint16_t *buf = vbuf;
1869 size_t count = size >> 1;
1872 ASSERT((size & 1) == 0);
1874 for (i = 0; i < count; i++)
1875 buf[i] = BSWAP_16(buf[i]);
1880 byteswap_uint8_array(void *vbuf, size_t size)
1894 zio_compress_init();
1902 arc_fini(); /* arc depends on l2arc, so arc must go first */
1905 zio_compress_fini();