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) 2012 by Delphix. All rights reserved.
24 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
28 #include <sys/dmu_impl.h>
29 #include <sys/dmu_tx.h>
31 #include <sys/dnode.h>
32 #include <sys/zfs_context.h>
33 #include <sys/dmu_objset.h>
34 #include <sys/dmu_traverse.h>
35 #include <sys/dsl_dataset.h>
36 #include <sys/dsl_dir.h>
37 #include <sys/dsl_pool.h>
38 #include <sys/dsl_synctask.h>
39 #include <sys/dsl_prop.h>
40 #include <sys/dmu_zfetch.h>
41 #include <sys/zfs_ioctl.h>
43 #include <sys/zio_checksum.h>
46 #include <sys/vmsystm.h>
47 #include <sys/zfs_znode.h>
50 const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
51 { DMU_BSWAP_UINT8, TRUE, "unallocated" },
52 { DMU_BSWAP_ZAP, TRUE, "object directory" },
53 { DMU_BSWAP_UINT64, TRUE, "object array" },
54 { DMU_BSWAP_UINT8, TRUE, "packed nvlist" },
55 { DMU_BSWAP_UINT64, TRUE, "packed nvlist size" },
56 { DMU_BSWAP_UINT64, TRUE, "bpobj" },
57 { DMU_BSWAP_UINT64, TRUE, "bpobj header" },
58 { DMU_BSWAP_UINT64, TRUE, "SPA space map header" },
59 { DMU_BSWAP_UINT64, TRUE, "SPA space map" },
60 { DMU_BSWAP_UINT64, TRUE, "ZIL intent log" },
61 { DMU_BSWAP_DNODE, TRUE, "DMU dnode" },
62 { DMU_BSWAP_OBJSET, TRUE, "DMU objset" },
63 { DMU_BSWAP_UINT64, TRUE, "DSL directory" },
64 { DMU_BSWAP_ZAP, TRUE, "DSL directory child map"},
65 { DMU_BSWAP_ZAP, TRUE, "DSL dataset snap map" },
66 { DMU_BSWAP_ZAP, TRUE, "DSL props" },
67 { DMU_BSWAP_UINT64, TRUE, "DSL dataset" },
68 { DMU_BSWAP_ZNODE, TRUE, "ZFS znode" },
69 { DMU_BSWAP_OLDACL, TRUE, "ZFS V0 ACL" },
70 { DMU_BSWAP_UINT8, FALSE, "ZFS plain file" },
71 { DMU_BSWAP_ZAP, TRUE, "ZFS directory" },
72 { DMU_BSWAP_ZAP, TRUE, "ZFS master node" },
73 { DMU_BSWAP_ZAP, TRUE, "ZFS delete queue" },
74 { DMU_BSWAP_UINT8, FALSE, "zvol object" },
75 { DMU_BSWAP_ZAP, TRUE, "zvol prop" },
76 { DMU_BSWAP_UINT8, FALSE, "other uint8[]" },
77 { DMU_BSWAP_UINT64, FALSE, "other uint64[]" },
78 { DMU_BSWAP_ZAP, TRUE, "other ZAP" },
79 { DMU_BSWAP_ZAP, TRUE, "persistent error log" },
80 { DMU_BSWAP_UINT8, TRUE, "SPA history" },
81 { DMU_BSWAP_UINT64, TRUE, "SPA history offsets" },
82 { DMU_BSWAP_ZAP, TRUE, "Pool properties" },
83 { DMU_BSWAP_ZAP, TRUE, "DSL permissions" },
84 { DMU_BSWAP_ACL, TRUE, "ZFS ACL" },
85 { DMU_BSWAP_UINT8, TRUE, "ZFS SYSACL" },
86 { DMU_BSWAP_UINT8, TRUE, "FUID table" },
87 { DMU_BSWAP_UINT64, TRUE, "FUID table size" },
88 { DMU_BSWAP_ZAP, TRUE, "DSL dataset next clones"},
89 { DMU_BSWAP_ZAP, TRUE, "scan work queue" },
90 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group used" },
91 { DMU_BSWAP_ZAP, TRUE, "ZFS user/group quota" },
92 { DMU_BSWAP_ZAP, TRUE, "snapshot refcount tags"},
93 { DMU_BSWAP_ZAP, TRUE, "DDT ZAP algorithm" },
94 { DMU_BSWAP_ZAP, TRUE, "DDT statistics" },
95 { DMU_BSWAP_UINT8, TRUE, "System attributes" },
96 { DMU_BSWAP_ZAP, TRUE, "SA master node" },
97 { DMU_BSWAP_ZAP, TRUE, "SA attr registration" },
98 { DMU_BSWAP_ZAP, TRUE, "SA attr layouts" },
99 { DMU_BSWAP_ZAP, TRUE, "scan translations" },
100 { DMU_BSWAP_UINT8, FALSE, "deduplicated block" },
101 { DMU_BSWAP_ZAP, TRUE, "DSL deadlist map" },
102 { DMU_BSWAP_UINT64, TRUE, "DSL deadlist map hdr" },
103 { DMU_BSWAP_ZAP, TRUE, "DSL dir clones" },
104 { DMU_BSWAP_UINT64, TRUE, "bpobj subobj" }
107 const dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = {
108 { byteswap_uint8_array, "uint8" },
109 { byteswap_uint16_array, "uint16" },
110 { byteswap_uint32_array, "uint32" },
111 { byteswap_uint64_array, "uint64" },
112 { zap_byteswap, "zap" },
113 { dnode_buf_byteswap, "dnode" },
114 { dmu_objset_byteswap, "objset" },
115 { zfs_znode_byteswap, "znode" },
116 { zfs_oldacl_byteswap, "oldacl" },
117 { zfs_acl_byteswap, "acl" }
121 dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
122 void *tag, dmu_buf_t **dbp, int flags)
128 int db_flags = DB_RF_CANFAIL;
130 if (flags & DMU_READ_NO_PREFETCH)
131 db_flags |= DB_RF_NOPREFETCH;
133 err = dnode_hold(os, object, FTAG, &dn);
136 blkid = dbuf_whichblock(dn, offset);
137 rw_enter(&dn->dn_struct_rwlock, RW_READER);
138 db = dbuf_hold(dn, blkid, tag);
139 rw_exit(&dn->dn_struct_rwlock);
143 err = dbuf_read(db, NULL, db_flags);
150 dnode_rele(dn, FTAG);
151 *dbp = &db->db; /* NULL db plus first field offset is NULL */
158 return (DN_MAX_BONUSLEN);
162 dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx)
164 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
171 if (dn->dn_bonus != db) {
173 } else if (newsize < 0 || newsize > db_fake->db_size) {
176 dnode_setbonuslen(dn, newsize, tx);
185 dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx)
187 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
194 if (!DMU_OT_IS_VALID(type)) {
196 } else if (dn->dn_bonus != db) {
199 dnode_setbonus_type(dn, type, tx);
208 dmu_get_bonustype(dmu_buf_t *db_fake)
210 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
212 dmu_object_type_t type;
216 type = dn->dn_bonustype;
223 dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx)
228 error = dnode_hold(os, object, FTAG, &dn);
229 dbuf_rm_spill(dn, tx);
230 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
231 dnode_rm_spill(dn, tx);
232 rw_exit(&dn->dn_struct_rwlock);
233 dnode_rele(dn, FTAG);
238 * returns ENOENT, EIO, or 0.
241 dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
247 error = dnode_hold(os, object, FTAG, &dn);
251 rw_enter(&dn->dn_struct_rwlock, RW_READER);
252 if (dn->dn_bonus == NULL) {
253 rw_exit(&dn->dn_struct_rwlock);
254 rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
255 if (dn->dn_bonus == NULL)
256 dbuf_create_bonus(dn);
260 /* as long as the bonus buf is held, the dnode will be held */
261 if (refcount_add(&db->db_holds, tag) == 1) {
262 VERIFY(dnode_add_ref(dn, db));
263 (void) atomic_inc_32_nv(&dn->dn_dbufs_count);
267 * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's
268 * hold and incrementing the dbuf count to ensure that dnode_move() sees
269 * a dnode hold for every dbuf.
271 rw_exit(&dn->dn_struct_rwlock);
273 dnode_rele(dn, FTAG);
275 VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH));
282 * returns ENOENT, EIO, or 0.
284 * This interface will allocate a blank spill dbuf when a spill blk
285 * doesn't already exist on the dnode.
287 * if you only want to find an already existing spill db, then
288 * dmu_spill_hold_existing() should be used.
291 dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp)
293 dmu_buf_impl_t *db = NULL;
296 if ((flags & DB_RF_HAVESTRUCT) == 0)
297 rw_enter(&dn->dn_struct_rwlock, RW_READER);
299 db = dbuf_hold(dn, DMU_SPILL_BLKID, tag);
301 if ((flags & DB_RF_HAVESTRUCT) == 0)
302 rw_exit(&dn->dn_struct_rwlock);
305 err = dbuf_read(db, NULL, flags);
314 dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
316 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
323 if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) {
326 rw_enter(&dn->dn_struct_rwlock, RW_READER);
328 if (!dn->dn_have_spill) {
331 err = dmu_spill_hold_by_dnode(dn,
332 DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp);
335 rw_exit(&dn->dn_struct_rwlock);
343 dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
345 dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
351 err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp);
358 * Note: longer-term, we should modify all of the dmu_buf_*() interfaces
359 * to take a held dnode rather than <os, object> -- the lookup is wasteful,
360 * and can induce severe lock contention when writing to several files
361 * whose dnodes are in the same block.
364 dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
365 int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
367 dsl_pool_t *dp = NULL;
369 uint64_t blkid, nblks, i;
375 ASSERT(length <= DMU_MAX_ACCESS);
377 dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
378 if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
379 dbuf_flags |= DB_RF_NOPREFETCH;
381 rw_enter(&dn->dn_struct_rwlock, RW_READER);
382 if (dn->dn_datablkshift) {
383 int blkshift = dn->dn_datablkshift;
384 nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
385 P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
387 if (offset + length > dn->dn_datablksz) {
388 zfs_panic_recover("zfs: accessing past end of object "
389 "%llx/%llx (size=%u access=%llu+%llu)",
390 (longlong_t)dn->dn_objset->
391 os_dsl_dataset->ds_object,
392 (longlong_t)dn->dn_object, dn->dn_datablksz,
393 (longlong_t)offset, (longlong_t)length);
394 rw_exit(&dn->dn_struct_rwlock);
399 dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_PUSHPAGE | KM_NODEBUG);
401 if (dn->dn_objset->os_dsl_dataset)
402 dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
403 if (dp && dsl_pool_sync_context(dp))
405 zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
406 blkid = dbuf_whichblock(dn, offset);
407 for (i = 0; i < nblks; i++) {
408 dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
410 rw_exit(&dn->dn_struct_rwlock);
411 dmu_buf_rele_array(dbp, nblks, tag);
415 /* initiate async i/o */
417 (void) dbuf_read(db, zio, dbuf_flags);
421 rw_exit(&dn->dn_struct_rwlock);
423 /* wait for async i/o */
425 /* track read overhead when we are in sync context */
426 if (dp && dsl_pool_sync_context(dp))
427 dp->dp_read_overhead += gethrtime() - start;
429 dmu_buf_rele_array(dbp, nblks, tag);
433 /* wait for other io to complete */
435 for (i = 0; i < nblks; i++) {
436 dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
437 mutex_enter(&db->db_mtx);
438 while (db->db_state == DB_READ ||
439 db->db_state == DB_FILL)
440 cv_wait(&db->db_changed, &db->db_mtx);
441 if (db->db_state == DB_UNCACHED)
443 mutex_exit(&db->db_mtx);
445 dmu_buf_rele_array(dbp, nblks, tag);
457 dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
458 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
463 err = dnode_hold(os, object, FTAG, &dn);
467 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
468 numbufsp, dbpp, DMU_READ_PREFETCH);
470 dnode_rele(dn, FTAG);
476 dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset,
477 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
479 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
485 err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
486 numbufsp, dbpp, DMU_READ_PREFETCH);
493 dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
496 dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
501 for (i = 0; i < numbufs; i++) {
503 dbuf_rele(dbp[i], tag);
506 kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
510 dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
516 if (zfs_prefetch_disable)
519 if (len == 0) { /* they're interested in the bonus buffer */
520 dn = DMU_META_DNODE(os);
522 if (object == 0 || object >= DN_MAX_OBJECT)
525 rw_enter(&dn->dn_struct_rwlock, RW_READER);
526 blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
527 dbuf_prefetch(dn, blkid);
528 rw_exit(&dn->dn_struct_rwlock);
533 * XXX - Note, if the dnode for the requested object is not
534 * already cached, we will do a *synchronous* read in the
535 * dnode_hold() call. The same is true for any indirects.
537 err = dnode_hold(os, object, FTAG, &dn);
541 rw_enter(&dn->dn_struct_rwlock, RW_READER);
542 if (dn->dn_datablkshift) {
543 int blkshift = dn->dn_datablkshift;
544 nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
545 P2ALIGN(offset, 1<<blkshift)) >> blkshift;
547 nblks = (offset < dn->dn_datablksz);
551 blkid = dbuf_whichblock(dn, offset);
552 for (i = 0; i < nblks; i++)
553 dbuf_prefetch(dn, blkid+i);
556 rw_exit(&dn->dn_struct_rwlock);
558 dnode_rele(dn, FTAG);
562 * Get the next "chunk" of file data to free. We traverse the file from
563 * the end so that the file gets shorter over time (if we crashes in the
564 * middle, this will leave us in a better state). We find allocated file
565 * data by simply searching the allocated level 1 indirects.
568 get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit)
570 uint64_t len = *start - limit;
572 uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1));
574 dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
576 ASSERT(limit <= *start);
578 if (len <= iblkrange * maxblks) {
582 ASSERT(ISP2(iblkrange));
584 while (*start > limit && blkcnt < maxblks) {
587 /* find next allocated L1 indirect */
588 err = dnode_next_offset(dn,
589 DNODE_FIND_BACKWARDS, start, 2, 1, 0);
591 /* if there are no more, then we are done */
600 /* reset offset to end of "next" block back */
601 *start = P2ALIGN(*start, iblkrange);
611 dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
612 uint64_t length, boolean_t free_dnode)
615 uint64_t object_size, start, end, len;
616 boolean_t trunc = (length == DMU_OBJECT_END);
619 align = 1 << dn->dn_datablkshift;
621 object_size = align == 1 ? dn->dn_datablksz :
622 (dn->dn_maxblkid + 1) << dn->dn_datablkshift;
624 end = offset + length;
625 if (trunc || end > object_size)
629 length = end - offset;
633 /* assert(offset <= start) */
634 err = get_next_chunk(dn, &start, offset);
637 len = trunc ? DMU_OBJECT_END : end - start;
639 tx = dmu_tx_create(os);
640 dmu_tx_hold_free(tx, dn->dn_object, start, len);
641 err = dmu_tx_assign(tx, TXG_WAIT);
647 dnode_free_range(dn, start, trunc ? -1 : len, tx);
649 if (start == 0 && free_dnode) {
654 length -= end - start;
663 dmu_free_long_range(objset_t *os, uint64_t object,
664 uint64_t offset, uint64_t length)
669 err = dnode_hold(os, object, FTAG, &dn);
672 err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
673 dnode_rele(dn, FTAG);
678 dmu_free_object(objset_t *os, uint64_t object)
684 err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
688 if (dn->dn_nlevels == 1) {
689 tx = dmu_tx_create(os);
690 dmu_tx_hold_bonus(tx, object);
691 dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
692 err = dmu_tx_assign(tx, TXG_WAIT);
694 dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
701 err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
703 dnode_rele(dn, FTAG);
708 dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
709 uint64_t size, dmu_tx_t *tx)
712 int err = dnode_hold(os, object, FTAG, &dn);
715 ASSERT(offset < UINT64_MAX);
716 ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
717 dnode_free_range(dn, offset, size, tx);
718 dnode_rele(dn, FTAG);
723 dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
724 void *buf, uint32_t flags)
730 err = dnode_hold(os, object, FTAG, &dn);
735 * Deal with odd block sizes, where there can't be data past the first
736 * block. If we ever do the tail block optimization, we will need to
737 * handle that here as well.
739 if (dn->dn_maxblkid == 0) {
740 int newsz = offset > dn->dn_datablksz ? 0 :
741 MIN(size, dn->dn_datablksz - offset);
742 bzero((char *)buf + newsz, size - newsz);
747 uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
751 * NB: we could do this block-at-a-time, but it's nice
752 * to be reading in parallel.
754 err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
755 TRUE, FTAG, &numbufs, &dbp, flags);
759 for (i = 0; i < numbufs; i++) {
762 dmu_buf_t *db = dbp[i];
766 bufoff = offset - db->db_offset;
767 tocpy = (int)MIN(db->db_size - bufoff, size);
769 bcopy((char *)db->db_data + bufoff, buf, tocpy);
773 buf = (char *)buf + tocpy;
775 dmu_buf_rele_array(dbp, numbufs, FTAG);
777 dnode_rele(dn, FTAG);
782 dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
783 const void *buf, dmu_tx_t *tx)
791 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
792 FALSE, FTAG, &numbufs, &dbp));
794 for (i = 0; i < numbufs; i++) {
797 dmu_buf_t *db = dbp[i];
801 bufoff = offset - db->db_offset;
802 tocpy = (int)MIN(db->db_size - bufoff, size);
804 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
806 if (tocpy == db->db_size)
807 dmu_buf_will_fill(db, tx);
809 dmu_buf_will_dirty(db, tx);
811 (void) memcpy((char *)db->db_data + bufoff, buf, tocpy);
813 if (tocpy == db->db_size)
814 dmu_buf_fill_done(db, tx);
818 buf = (char *)buf + tocpy;
820 dmu_buf_rele_array(dbp, numbufs, FTAG);
824 dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
833 VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
834 FALSE, FTAG, &numbufs, &dbp));
836 for (i = 0; i < numbufs; i++) {
837 dmu_buf_t *db = dbp[i];
839 dmu_buf_will_not_fill(db, tx);
841 dmu_buf_rele_array(dbp, numbufs, FTAG);
845 * DMU support for xuio
847 kstat_t *xuio_ksp = NULL;
849 typedef struct xuio_stats {
850 /* loaned yet not returned arc_buf */
851 kstat_named_t xuiostat_onloan_rbuf;
852 kstat_named_t xuiostat_onloan_wbuf;
853 /* whether a copy is made when loaning out a read buffer */
854 kstat_named_t xuiostat_rbuf_copied;
855 kstat_named_t xuiostat_rbuf_nocopy;
856 /* whether a copy is made when assigning a write buffer */
857 kstat_named_t xuiostat_wbuf_copied;
858 kstat_named_t xuiostat_wbuf_nocopy;
861 static xuio_stats_t xuio_stats = {
862 { "onloan_read_buf", KSTAT_DATA_UINT64 },
863 { "onloan_write_buf", KSTAT_DATA_UINT64 },
864 { "read_buf_copied", KSTAT_DATA_UINT64 },
865 { "read_buf_nocopy", KSTAT_DATA_UINT64 },
866 { "write_buf_copied", KSTAT_DATA_UINT64 },
867 { "write_buf_nocopy", KSTAT_DATA_UINT64 }
870 #define XUIOSTAT_INCR(stat, val) \
871 atomic_add_64(&xuio_stats.stat.value.ui64, (val))
872 #define XUIOSTAT_BUMP(stat) XUIOSTAT_INCR(stat, 1)
875 dmu_xuio_init(xuio_t *xuio, int nblk)
878 uio_t *uio = &xuio->xu_uio;
880 uio->uio_iovcnt = nblk;
881 uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_PUSHPAGE);
883 priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_PUSHPAGE);
885 priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_PUSHPAGE);
886 priv->iovp = uio->uio_iov;
887 XUIO_XUZC_PRIV(xuio) = priv;
889 if (XUIO_XUZC_RW(xuio) == UIO_READ)
890 XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk);
892 XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk);
898 dmu_xuio_fini(xuio_t *xuio)
900 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
901 int nblk = priv->cnt;
903 kmem_free(priv->iovp, nblk * sizeof (iovec_t));
904 kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *));
905 kmem_free(priv, sizeof (dmu_xuio_t));
907 if (XUIO_XUZC_RW(xuio) == UIO_READ)
908 XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk);
910 XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk);
914 * Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf }
915 * and increase priv->next by 1.
918 dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n)
921 uio_t *uio = &xuio->xu_uio;
922 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
923 int i = priv->next++;
925 ASSERT(i < priv->cnt);
926 ASSERT(off + n <= arc_buf_size(abuf));
927 iov = uio->uio_iov + i;
928 iov->iov_base = (char *)abuf->b_data + off;
930 priv->bufs[i] = abuf;
935 dmu_xuio_cnt(xuio_t *xuio)
937 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
942 dmu_xuio_arcbuf(xuio_t *xuio, int i)
944 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
946 ASSERT(i < priv->cnt);
947 return (priv->bufs[i]);
951 dmu_xuio_clear(xuio_t *xuio, int i)
953 dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
955 ASSERT(i < priv->cnt);
956 priv->bufs[i] = NULL;
962 xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc",
963 KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t),
965 if (xuio_ksp != NULL) {
966 xuio_ksp->ks_data = &xuio_stats;
967 kstat_install(xuio_ksp);
974 if (xuio_ksp != NULL) {
975 kstat_delete(xuio_ksp);
981 xuio_stat_wbuf_copied()
983 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
987 xuio_stat_wbuf_nocopy()
989 XUIOSTAT_BUMP(xuiostat_wbuf_nocopy);
995 * Copy up to size bytes between arg_buf and req based on the data direction
996 * described by the req. If an entire req's data cannot be transfered the
997 * req's is updated such that it's current index and bv offsets correctly
998 * reference any residual data which could not be copied. The return value
999 * is the number of bytes successfully copied to arg_buf.
1002 dmu_req_copy(void *arg_buf, int size, int *offset, struct request *req)
1005 struct req_iterator iter;
1010 rq_for_each_segment(bv, req, iter) {
1012 /* Fully consumed the passed arg_buf */
1013 ASSERT3S(*offset, <=, size);
1014 if (size == *offset)
1017 /* Skip fully consumed bv's */
1018 if (bv->bv_len == 0)
1021 tocpy = MIN(bv->bv_len, size - *offset);
1022 ASSERT3S(tocpy, >=, 0);
1024 bv_buf = page_address(bv->bv_page) + bv->bv_offset;
1025 ASSERT3P(bv_buf, !=, NULL);
1027 if (rq_data_dir(req) == WRITE)
1028 memcpy(arg_buf + *offset, bv_buf, tocpy);
1030 memcpy(bv_buf, arg_buf + *offset, tocpy);
1033 bv->bv_offset += tocpy;
1034 bv->bv_len -= tocpy;
1041 dmu_bio_put(struct bio *bio)
1043 struct bio *bio_next;
1046 bio_next = bio->bi_next;
1053 dmu_bio_clone(struct bio *bio, struct bio **bio_copy)
1055 struct bio *bio_root = NULL;
1056 struct bio *bio_last = NULL;
1057 struct bio *bio_new;
1063 bio_new = bio_clone(bio, GFP_NOIO);
1064 if (bio_new == NULL) {
1065 dmu_bio_put(bio_root);
1070 bio_last->bi_next = bio_new;
1080 *bio_copy = bio_root;
1086 dmu_read_req(objset_t *os, uint64_t object, struct request *req)
1088 uint64_t size = blk_rq_bytes(req);
1089 uint64_t offset = blk_rq_pos(req) << 9;
1090 struct bio *bio_saved = req->bio;
1092 int numbufs, i, err;
1095 * NB: we could do this block-at-a-time, but it's nice
1096 * to be reading in parallel.
1098 err = dmu_buf_hold_array(os, object, offset, size, TRUE, FTAG,
1104 * Clone the bio list so the bv->bv_offset and bv->bv_len members
1105 * can be safely modified. The original bio list is relinked in to
1106 * the request when the function exits. This is required because
1107 * some file systems blindly assume that these values will remain
1108 * constant between bio_submit() and the IO completion callback.
1110 err = dmu_bio_clone(bio_saved, &req->bio);
1114 for (i = 0; i < numbufs; i++) {
1115 int tocpy, didcpy, bufoff;
1116 dmu_buf_t *db = dbp[i];
1118 bufoff = offset - db->db_offset;
1119 ASSERT3S(bufoff, >=, 0);
1121 tocpy = (int)MIN(db->db_size - bufoff, size);
1125 err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
1138 dmu_bio_put(req->bio);
1139 req->bio = bio_saved;
1141 dmu_buf_rele_array(dbp, numbufs, FTAG);
1147 dmu_write_req(objset_t *os, uint64_t object, struct request *req, dmu_tx_t *tx)
1149 uint64_t size = blk_rq_bytes(req);
1150 uint64_t offset = blk_rq_pos(req) << 9;
1151 struct bio *bio_saved = req->bio;
1160 err = dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG,
1166 * Clone the bio list so the bv->bv_offset and bv->bv_len members
1167 * can be safely modified. The original bio list is relinked in to
1168 * the request when the function exits. This is required because
1169 * some file systems blindly assume that these values will remain
1170 * constant between bio_submit() and the IO completion callback.
1172 err = dmu_bio_clone(bio_saved, &req->bio);
1176 for (i = 0; i < numbufs; i++) {
1177 int tocpy, didcpy, bufoff;
1178 dmu_buf_t *db = dbp[i];
1180 bufoff = offset - db->db_offset;
1181 ASSERT3S(bufoff, >=, 0);
1183 tocpy = (int)MIN(db->db_size - bufoff, size);
1187 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1189 if (tocpy == db->db_size)
1190 dmu_buf_will_fill(db, tx);
1192 dmu_buf_will_dirty(db, tx);
1194 err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
1196 if (tocpy == db->db_size)
1197 dmu_buf_fill_done(db, tx);
1210 dmu_bio_put(req->bio);
1211 req->bio = bio_saved;
1213 dmu_buf_rele_array(dbp, numbufs, FTAG);
1219 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
1222 int numbufs, i, err;
1223 xuio_t *xuio = NULL;
1226 * NB: we could do this block-at-a-time, but it's nice
1227 * to be reading in parallel.
1229 err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
1234 for (i = 0; i < numbufs; i++) {
1237 dmu_buf_t *db = dbp[i];
1241 bufoff = uio->uio_loffset - db->db_offset;
1242 tocpy = (int)MIN(db->db_size - bufoff, size);
1245 dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db;
1246 arc_buf_t *dbuf_abuf = dbi->db_buf;
1247 arc_buf_t *abuf = dbuf_loan_arcbuf(dbi);
1248 err = dmu_xuio_add(xuio, abuf, bufoff, tocpy);
1250 uio->uio_resid -= tocpy;
1251 uio->uio_loffset += tocpy;
1254 if (abuf == dbuf_abuf)
1255 XUIOSTAT_BUMP(xuiostat_rbuf_nocopy);
1257 XUIOSTAT_BUMP(xuiostat_rbuf_copied);
1259 err = uiomove((char *)db->db_data + bufoff, tocpy,
1267 dmu_buf_rele_array(dbp, numbufs, FTAG);
1273 dmu_write_uio_dnode(dnode_t *dn, uio_t *uio, uint64_t size, dmu_tx_t *tx)
1280 err = dmu_buf_hold_array_by_dnode(dn, uio->uio_loffset, size,
1281 FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH);
1285 for (i = 0; i < numbufs; i++) {
1288 dmu_buf_t *db = dbp[i];
1292 bufoff = uio->uio_loffset - db->db_offset;
1293 tocpy = (int)MIN(db->db_size - bufoff, size);
1295 ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
1297 if (tocpy == db->db_size)
1298 dmu_buf_will_fill(db, tx);
1300 dmu_buf_will_dirty(db, tx);
1303 * XXX uiomove could block forever (eg.nfs-backed
1304 * pages). There needs to be a uiolockdown() function
1305 * to lock the pages in memory, so that uiomove won't
1308 err = uiomove((char *)db->db_data + bufoff, tocpy,
1311 if (tocpy == db->db_size)
1312 dmu_buf_fill_done(db, tx);
1320 dmu_buf_rele_array(dbp, numbufs, FTAG);
1325 dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size,
1328 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
1337 err = dmu_write_uio_dnode(dn, uio, size, tx);
1344 dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
1353 err = dnode_hold(os, object, FTAG, &dn);
1357 err = dmu_write_uio_dnode(dn, uio, size, tx);
1359 dnode_rele(dn, FTAG);
1363 #endif /* _KERNEL */
1366 * Allocate a loaned anonymous arc buffer.
1369 dmu_request_arcbuf(dmu_buf_t *handle, int size)
1371 dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
1374 DB_GET_SPA(&spa, db);
1375 return (arc_loan_buf(spa, size));
1379 * Free a loaned arc buffer.
1382 dmu_return_arcbuf(arc_buf_t *buf)
1384 arc_return_buf(buf, FTAG);
1385 VERIFY(arc_buf_remove_ref(buf, FTAG) == 1);
1389 * When possible directly assign passed loaned arc buffer to a dbuf.
1390 * If this is not possible copy the contents of passed arc buf via
1394 dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
1397 dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle;
1400 uint32_t blksz = (uint32_t)arc_buf_size(buf);
1403 DB_DNODE_ENTER(dbuf);
1404 dn = DB_DNODE(dbuf);
1405 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1406 blkid = dbuf_whichblock(dn, offset);
1407 VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
1408 rw_exit(&dn->dn_struct_rwlock);
1409 DB_DNODE_EXIT(dbuf);
1411 if (offset == db->db.db_offset && blksz == db->db.db_size) {
1412 dbuf_assign_arcbuf(db, buf, tx);
1413 dbuf_rele(db, FTAG);
1418 DB_DNODE_ENTER(dbuf);
1419 dn = DB_DNODE(dbuf);
1421 object = dn->dn_object;
1422 DB_DNODE_EXIT(dbuf);
1424 dbuf_rele(db, FTAG);
1425 dmu_write(os, object, offset, blksz, buf->b_data, tx);
1426 dmu_return_arcbuf(buf);
1427 XUIOSTAT_BUMP(xuiostat_wbuf_copied);
1432 dbuf_dirty_record_t *dsa_dr;
1433 dmu_sync_cb_t *dsa_done;
1440 dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
1442 dmu_sync_arg_t *dsa = varg;
1443 dmu_buf_t *db = dsa->dsa_zgd->zgd_db;
1444 blkptr_t *bp = zio->io_bp;
1446 if (zio->io_error == 0) {
1447 if (BP_IS_HOLE(bp)) {
1449 * A block of zeros may compress to a hole, but the
1450 * block size still needs to be known for replay.
1452 BP_SET_LSIZE(bp, db->db_size);
1454 ASSERT(BP_GET_LEVEL(bp) == 0);
1461 dmu_sync_late_arrival_ready(zio_t *zio)
1463 dmu_sync_ready(zio, NULL, zio->io_private);
1468 dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
1470 dmu_sync_arg_t *dsa = varg;
1471 dbuf_dirty_record_t *dr = dsa->dsa_dr;
1472 dmu_buf_impl_t *db = dr->dr_dbuf;
1474 mutex_enter(&db->db_mtx);
1475 ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
1476 if (zio->io_error == 0) {
1477 dr->dt.dl.dr_overridden_by = *zio->io_bp;
1478 dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
1479 dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
1480 if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by))
1481 BP_ZERO(&dr->dt.dl.dr_overridden_by);
1483 dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
1485 cv_broadcast(&db->db_changed);
1486 mutex_exit(&db->db_mtx);
1488 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1490 kmem_free(dsa, sizeof (*dsa));
1494 dmu_sync_late_arrival_done(zio_t *zio)
1496 blkptr_t *bp = zio->io_bp;
1497 dmu_sync_arg_t *dsa = zio->io_private;
1499 if (zio->io_error == 0 && !BP_IS_HOLE(bp)) {
1500 ASSERT(zio->io_bp->blk_birth == zio->io_txg);
1501 ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa));
1502 zio_free(zio->io_spa, zio->io_txg, zio->io_bp);
1505 dmu_tx_commit(dsa->dsa_tx);
1507 dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
1509 kmem_free(dsa, sizeof (*dsa));
1513 dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd,
1514 zio_prop_t *zp, zbookmark_t *zb)
1516 dmu_sync_arg_t *dsa;
1519 tx = dmu_tx_create(os);
1520 dmu_tx_hold_space(tx, zgd->zgd_db->db_size);
1521 if (dmu_tx_assign(tx, TXG_WAIT) != 0) {
1523 return (EIO); /* Make zl_get_data do txg_waited_synced() */
1526 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_PUSHPAGE);
1528 dsa->dsa_done = done;
1532 zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp,
1533 zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp,
1534 dmu_sync_late_arrival_ready, dmu_sync_late_arrival_done, dsa,
1535 ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL | ZIO_FLAG_FASTWRITE, zb));
1541 * Intent log support: sync the block associated with db to disk.
1542 * N.B. and XXX: the caller is responsible for making sure that the
1543 * data isn't changing while dmu_sync() is writing it.
1547 * EEXIST: this txg has already been synced, so there's nothing to to.
1548 * The caller should not log the write.
1550 * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
1551 * The caller should not log the write.
1553 * EALREADY: this block is already in the process of being synced.
1554 * The caller should track its progress (somehow).
1556 * EIO: could not do the I/O.
1557 * The caller should do a txg_wait_synced().
1559 * 0: the I/O has been initiated.
1560 * The caller should log this blkptr in the done callback.
1561 * It is possible that the I/O will fail, in which case
1562 * the error will be reported to the done callback and
1563 * propagated to pio from zio_done().
1566 dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd)
1568 blkptr_t *bp = zgd->zgd_bp;
1569 dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db;
1570 objset_t *os = db->db_objset;
1571 dsl_dataset_t *ds = os->os_dsl_dataset;
1572 dbuf_dirty_record_t *dr;
1573 dmu_sync_arg_t *dsa;
1578 ASSERT(pio != NULL);
1579 ASSERT(BP_IS_HOLE(bp));
1582 SET_BOOKMARK(&zb, ds->ds_object,
1583 db->db.db_object, db->db_level, db->db_blkid);
1587 dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp);
1591 * If we're frozen (running ziltest), we always need to generate a bp.
1593 if (txg > spa_freeze_txg(os->os_spa))
1594 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1597 * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf()
1598 * and us. If we determine that this txg is not yet syncing,
1599 * but it begins to sync a moment later, that's OK because the
1600 * sync thread will block in dbuf_sync_leaf() until we drop db_mtx.
1602 mutex_enter(&db->db_mtx);
1604 if (txg <= spa_last_synced_txg(os->os_spa)) {
1606 * This txg has already synced. There's nothing to do.
1608 mutex_exit(&db->db_mtx);
1612 if (txg <= spa_syncing_txg(os->os_spa)) {
1614 * This txg is currently syncing, so we can't mess with
1615 * the dirty record anymore; just write a new log block.
1617 mutex_exit(&db->db_mtx);
1618 return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
1621 dr = db->db_last_dirty;
1622 while (dr && dr->dr_txg != txg)
1627 * There's no dr for this dbuf, so it must have been freed.
1628 * There's no need to log writes to freed blocks, so we're done.
1630 mutex_exit(&db->db_mtx);
1634 ASSERT(dr->dr_txg == txg);
1635 if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC ||
1636 dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
1638 * We have already issued a sync write for this buffer,
1639 * or this buffer has already been synced. It could not
1640 * have been dirtied since, or we would have cleared the state.
1642 mutex_exit(&db->db_mtx);
1646 ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN);
1647 dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
1648 mutex_exit(&db->db_mtx);
1650 dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_PUSHPAGE);
1652 dsa->dsa_done = done;
1656 zio_nowait(arc_write(pio, os->os_spa, txg,
1657 bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db),
1658 DBUF_IS_L2COMPRESSIBLE(db), &zp, dmu_sync_ready, dmu_sync_done,
1659 dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL | ZIO_FLAG_FASTWRITE, &zb));
1665 dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
1671 err = dnode_hold(os, object, FTAG, &dn);
1674 err = dnode_set_blksz(dn, size, ibs, tx);
1675 dnode_rele(dn, FTAG);
1680 dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
1685 /* XXX assumes dnode_hold will not get an i/o error */
1686 (void) dnode_hold(os, object, FTAG, &dn);
1687 ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
1688 dn->dn_checksum = checksum;
1689 dnode_setdirty(dn, tx);
1690 dnode_rele(dn, FTAG);
1694 dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
1699 /* XXX assumes dnode_hold will not get an i/o error */
1700 (void) dnode_hold(os, object, FTAG, &dn);
1701 ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
1702 dn->dn_compress = compress;
1703 dnode_setdirty(dn, tx);
1704 dnode_rele(dn, FTAG);
1707 int zfs_mdcomp_disable = 0;
1710 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
1712 dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET;
1713 boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) ||
1715 enum zio_checksum checksum = os->os_checksum;
1716 enum zio_compress compress = os->os_compress;
1717 enum zio_checksum dedup_checksum = os->os_dedup_checksum;
1719 boolean_t dedup_verify = os->os_dedup_verify;
1720 int copies = os->os_copies;
1723 * Determine checksum setting.
1727 * Metadata always gets checksummed. If the data
1728 * checksum is multi-bit correctable, and it's not a
1729 * ZBT-style checksum, then it's suitable for metadata
1730 * as well. Otherwise, the metadata checksum defaults
1733 if (zio_checksum_table[checksum].ci_correctable < 1 ||
1734 zio_checksum_table[checksum].ci_eck)
1735 checksum = ZIO_CHECKSUM_FLETCHER_4;
1737 checksum = zio_checksum_select(dn->dn_checksum, checksum);
1741 * Determine compression setting.
1745 * XXX -- we should design a compression algorithm
1746 * that specializes in arrays of bps.
1748 compress = zfs_mdcomp_disable ? ZIO_COMPRESS_EMPTY :
1751 compress = zio_compress_select(dn->dn_compress, compress);
1755 * Determine dedup setting. If we are in dmu_sync(), we won't
1756 * actually dedup now because that's all done in syncing context;
1757 * but we do want to use the dedup checkum. If the checksum is not
1758 * strong enough to ensure unique signatures, force dedup_verify.
1760 dedup = (!ismd && dedup_checksum != ZIO_CHECKSUM_OFF);
1762 checksum = dedup_checksum;
1763 if (!zio_checksum_table[checksum].ci_dedup)
1767 if (wp & WP_DMU_SYNC)
1770 if (wp & WP_NOFILL) {
1771 ASSERT(!ismd && level == 0);
1772 checksum = ZIO_CHECKSUM_OFF;
1773 compress = ZIO_COMPRESS_OFF;
1777 zp->zp_checksum = checksum;
1778 zp->zp_compress = compress;
1779 zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
1780 zp->zp_level = level;
1781 zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa));
1782 zp->zp_dedup = dedup;
1783 zp->zp_dedup_verify = dedup && dedup_verify;
1787 dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
1792 err = dnode_hold(os, object, FTAG, &dn);
1796 * Sync any current changes before
1797 * we go trundling through the block pointers.
1799 for (i = 0; i < TXG_SIZE; i++) {
1800 if (list_link_active(&dn->dn_dirty_link[i]))
1803 if (i != TXG_SIZE) {
1804 dnode_rele(dn, FTAG);
1805 txg_wait_synced(dmu_objset_pool(os), 0);
1806 err = dnode_hold(os, object, FTAG, &dn);
1811 err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
1812 dnode_rele(dn, FTAG);
1818 dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
1823 rw_enter(&dn->dn_struct_rwlock, RW_READER);
1824 mutex_enter(&dn->dn_mtx);
1828 doi->doi_data_block_size = dn->dn_datablksz;
1829 doi->doi_metadata_block_size = dn->dn_indblkshift ?
1830 1ULL << dn->dn_indblkshift : 0;
1831 doi->doi_type = dn->dn_type;
1832 doi->doi_bonus_type = dn->dn_bonustype;
1833 doi->doi_bonus_size = dn->dn_bonuslen;
1834 doi->doi_indirection = dn->dn_nlevels;
1835 doi->doi_checksum = dn->dn_checksum;
1836 doi->doi_compress = dn->dn_compress;
1837 doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
1838 doi->doi_max_offset = (dnp->dn_maxblkid + 1) * dn->dn_datablksz;
1839 doi->doi_fill_count = 0;
1840 for (i = 0; i < dnp->dn_nblkptr; i++)
1841 doi->doi_fill_count += dnp->dn_blkptr[i].blk_fill;
1843 mutex_exit(&dn->dn_mtx);
1844 rw_exit(&dn->dn_struct_rwlock);
1848 * Get information on a DMU object.
1849 * If doi is NULL, just indicates whether the object exists.
1852 dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
1855 int err = dnode_hold(os, object, FTAG, &dn);
1861 dmu_object_info_from_dnode(dn, doi);
1863 dnode_rele(dn, FTAG);
1868 * As above, but faster; can be used when you have a held dbuf in hand.
1871 dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi)
1873 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1876 dmu_object_info_from_dnode(DB_DNODE(db), doi);
1881 * Faster still when you only care about the size.
1882 * This is specifically optimized for zfs_getattr().
1885 dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize,
1886 u_longlong_t *nblk512)
1888 dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
1894 *blksize = dn->dn_datablksz;
1895 /* add 1 for dnode space */
1896 *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
1897 SPA_MINBLOCKSHIFT) + 1;
1902 byteswap_uint64_array(void *vbuf, size_t size)
1904 uint64_t *buf = vbuf;
1905 size_t count = size >> 3;
1908 ASSERT((size & 7) == 0);
1910 for (i = 0; i < count; i++)
1911 buf[i] = BSWAP_64(buf[i]);
1915 byteswap_uint32_array(void *vbuf, size_t size)
1917 uint32_t *buf = vbuf;
1918 size_t count = size >> 2;
1921 ASSERT((size & 3) == 0);
1923 for (i = 0; i < count; i++)
1924 buf[i] = BSWAP_32(buf[i]);
1928 byteswap_uint16_array(void *vbuf, size_t size)
1930 uint16_t *buf = vbuf;
1931 size_t count = size >> 1;
1934 ASSERT((size & 1) == 0);
1936 for (i = 0; i < count; i++)
1937 buf[i] = BSWAP_16(buf[i]);
1942 byteswap_uint8_array(void *vbuf, size_t size)
1976 #if defined(_KERNEL) && defined(HAVE_SPL)
1977 EXPORT_SYMBOL(dmu_bonus_hold);
1978 EXPORT_SYMBOL(dmu_buf_hold_array_by_bonus);
1979 EXPORT_SYMBOL(dmu_buf_rele_array);
1980 EXPORT_SYMBOL(dmu_prefetch);
1981 EXPORT_SYMBOL(dmu_free_range);
1982 EXPORT_SYMBOL(dmu_free_long_range);
1983 EXPORT_SYMBOL(dmu_free_object);
1984 EXPORT_SYMBOL(dmu_read);
1985 EXPORT_SYMBOL(dmu_write);
1986 EXPORT_SYMBOL(dmu_prealloc);
1987 EXPORT_SYMBOL(dmu_object_info);
1988 EXPORT_SYMBOL(dmu_object_info_from_dnode);
1989 EXPORT_SYMBOL(dmu_object_info_from_db);
1990 EXPORT_SYMBOL(dmu_object_size_from_db);
1991 EXPORT_SYMBOL(dmu_object_set_blocksize);
1992 EXPORT_SYMBOL(dmu_object_set_checksum);
1993 EXPORT_SYMBOL(dmu_object_set_compress);
1994 EXPORT_SYMBOL(dmu_write_policy);
1995 EXPORT_SYMBOL(dmu_sync);
1996 EXPORT_SYMBOL(dmu_request_arcbuf);
1997 EXPORT_SYMBOL(dmu_return_arcbuf);
1998 EXPORT_SYMBOL(dmu_assign_arcbuf);
1999 EXPORT_SYMBOL(dmu_buf_hold);
2000 EXPORT_SYMBOL(dmu_ot);
2002 module_param(zfs_mdcomp_disable, int, 0644);
2003 MODULE_PARM_DESC(zfs_mdcomp_disable, "Disable meta data compression");