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, 2018 by Delphix. All rights reserved.
26 #include <sys/zfs_context.h>
27 #include <sys/dmu_objset.h>
28 #include <sys/dmu_traverse.h>
29 #include <sys/dsl_dataset.h>
30 #include <sys/dsl_dir.h>
31 #include <sys/dsl_pool.h>
32 #include <sys/dnode.h>
34 #include <sys/spa_impl.h>
36 #include <sys/dmu_impl.h>
38 #include <sys/sa_impl.h>
39 #include <sys/callb.h>
40 #include <sys/zfeature.h>
42 static int32_t zfs_pd_bytes_max = 50 * 1024 * 1024; /* 50MB */
43 static int32_t send_holes_without_birth_time = 1;
44 static int32_t zfs_traverse_indirect_prefetch_limit = 32;
46 typedef struct prefetch_data {
49 int32_t pd_bytes_fetched;
53 zbookmark_phys_t pd_resume;
56 typedef struct traverse_data {
61 zbookmark_phys_t *td_resume;
63 prefetch_data_t *td_pfd;
65 uint64_t td_hole_birth_enabled_txg;
68 boolean_t td_realloc_possible;
71 static int traverse_dnode(traverse_data_t *td, const blkptr_t *bp,
72 const dnode_phys_t *dnp, uint64_t objset, uint64_t object);
73 static void prefetch_dnode_metadata(traverse_data_t *td, const dnode_phys_t *,
74 uint64_t objset, uint64_t object);
77 traverse_zil_block(zilog_t *zilog, const blkptr_t *bp, void *arg,
80 traverse_data_t *td = arg;
86 if (claim_txg == 0 && bp->blk_birth >= spa_min_claim_txg(td->td_spa))
89 SET_BOOKMARK(&zb, td->td_objset, ZB_ZIL_OBJECT, ZB_ZIL_LEVEL,
90 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]);
92 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL, td->td_arg);
98 traverse_zil_record(zilog_t *zilog, const lr_t *lrc, void *arg,
101 traverse_data_t *td = arg;
103 if (lrc->lrc_txtype == TX_WRITE) {
104 lr_write_t *lr = (lr_write_t *)lrc;
105 blkptr_t *bp = &lr->lr_blkptr;
111 if (claim_txg == 0 || bp->blk_birth < claim_txg)
114 SET_BOOKMARK(&zb, td->td_objset, lr->lr_foid,
115 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp));
117 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL,
124 traverse_zil(traverse_data_t *td, zil_header_t *zh)
126 uint64_t claim_txg = zh->zh_claim_txg;
129 * We only want to visit blocks that have been claimed but not yet
130 * replayed; plus blocks that are already stable in read-only mode.
132 if (claim_txg == 0 && spa_writeable(td->td_spa))
135 zilog_t *zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh);
136 (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td,
137 claim_txg, !(td->td_flags & TRAVERSE_NO_DECRYPT));
141 typedef enum resume_skip {
148 * Returns RESUME_SKIP_ALL if td indicates that we are resuming a traversal and
149 * the block indicated by zb does not need to be visited at all. Returns
150 * RESUME_SKIP_CHILDREN if we are resuming a post traversal and we reach the
151 * resume point. This indicates that this block should be visited but not its
152 * children (since they must have been visited in a previous traversal).
153 * Otherwise returns RESUME_SKIP_NONE.
156 resume_skip_check(traverse_data_t *td, const dnode_phys_t *dnp,
157 const zbookmark_phys_t *zb)
159 if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) {
161 * If we already visited this bp & everything below,
162 * don't bother doing it again.
164 if (zbookmark_subtree_completed(dnp, zb, td->td_resume))
165 return (RESUME_SKIP_ALL);
168 * If we found the block we're trying to resume from, zero
169 * the bookmark out to indicate that we have resumed.
171 if (memcmp(zb, td->td_resume, sizeof (*zb)) == 0) {
172 memset(td->td_resume, 0, sizeof (*zb));
173 if (td->td_flags & TRAVERSE_POST)
174 return (RESUME_SKIP_CHILDREN);
177 return (RESUME_SKIP_NONE);
181 * Returns B_TRUE, if prefetch read is issued, otherwise B_FALSE.
184 traverse_prefetch_metadata(traverse_data_t *td,
185 const blkptr_t *bp, const zbookmark_phys_t *zb)
187 arc_flags_t flags = ARC_FLAG_NOWAIT | ARC_FLAG_PREFETCH;
188 int zio_flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE;
190 if (!(td->td_flags & TRAVERSE_PREFETCH_METADATA))
193 * If we are in the process of resuming, don't prefetch, because
194 * some children will not be needed (and in fact may have already
197 if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume))
199 if (BP_IS_HOLE(bp) || bp->blk_birth <= td->td_min_txg)
201 if (BP_GET_LEVEL(bp) == 0 && BP_GET_TYPE(bp) != DMU_OT_DNODE)
203 ASSERT(!BP_IS_REDACTED(bp));
205 if ((td->td_flags & TRAVERSE_NO_DECRYPT) && BP_IS_PROTECTED(bp))
206 zio_flags |= ZIO_FLAG_RAW;
208 (void) arc_read(NULL, td->td_spa, bp, NULL, NULL,
209 ZIO_PRIORITY_ASYNC_READ, zio_flags, &flags, zb);
214 prefetch_needed(prefetch_data_t *pfd, const blkptr_t *bp)
216 ASSERT(pfd->pd_flags & TRAVERSE_PREFETCH_DATA);
217 if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp) ||
218 BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG || BP_IS_REDACTED(bp))
224 traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp,
225 const blkptr_t *bp, const zbookmark_phys_t *zb)
228 arc_buf_t *buf = NULL;
229 prefetch_data_t *pd = td->td_pfd;
231 switch (resume_skip_check(td, dnp, zb)) {
232 case RESUME_SKIP_ALL:
234 case RESUME_SKIP_CHILDREN:
236 case RESUME_SKIP_NONE:
242 if (bp->blk_birth == 0) {
244 * Since this block has a birth time of 0 it must be one of
245 * two things: a hole created before the
246 * SPA_FEATURE_HOLE_BIRTH feature was enabled, or a hole
247 * which has always been a hole in an object.
249 * If a file is written sparsely, then the unwritten parts of
250 * the file were "always holes" -- that is, they have been
251 * holes since this object was allocated. However, we (and
252 * our callers) can not necessarily tell when an object was
253 * allocated. Therefore, if it's possible that this object
254 * was freed and then its object number reused, we need to
255 * visit all the holes with birth==0.
257 * If it isn't possible that the object number was reused,
258 * then if SPA_FEATURE_HOLE_BIRTH was enabled before we wrote
259 * all the blocks we will visit as part of this traversal,
260 * then this hole must have always existed, so we can skip
261 * it. We visit blocks born after (exclusive) td_min_txg.
263 * Note that the meta-dnode cannot be reallocated.
265 if (!send_holes_without_birth_time &&
266 (!td->td_realloc_possible ||
267 zb->zb_object == DMU_META_DNODE_OBJECT) &&
268 td->td_hole_birth_enabled_txg <= td->td_min_txg)
270 } else if (bp->blk_birth <= td->td_min_txg) {
274 if (pd != NULL && !pd->pd_exited && prefetch_needed(pd, bp)) {
275 uint64_t size = BP_GET_LSIZE(bp);
276 mutex_enter(&pd->pd_mtx);
277 ASSERT(pd->pd_bytes_fetched >= 0);
278 while (pd->pd_bytes_fetched < size && !pd->pd_exited)
279 cv_wait_sig(&pd->pd_cv, &pd->pd_mtx);
280 pd->pd_bytes_fetched -= size;
281 cv_broadcast(&pd->pd_cv);
282 mutex_exit(&pd->pd_mtx);
285 if (BP_IS_HOLE(bp) || BP_IS_REDACTED(bp)) {
286 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg);
292 if (td->td_flags & TRAVERSE_PRE) {
293 err = td->td_func(td->td_spa, NULL, bp, zb, dnp,
295 if (err == TRAVERSE_VISIT_NO_CHILDREN)
301 if (BP_GET_LEVEL(bp) > 0) {
302 uint32_t flags = ARC_FLAG_WAIT;
303 int32_t i, ptidx, pidx;
304 uint32_t prefetchlimit;
305 int32_t epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT;
306 zbookmark_phys_t *czb;
308 ASSERT(!BP_IS_PROTECTED(bp));
310 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf,
311 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb);
315 czb = kmem_alloc(sizeof (zbookmark_phys_t), KM_SLEEP);
318 * When performing a traversal it is beneficial to
319 * asynchronously read-ahead the upcoming indirect
320 * blocks since they will be needed shortly. However,
321 * since a 128k indirect (non-L0) block may contain up
322 * to 1024 128-byte block pointers, its preferable to not
323 * prefetch them all at once. Issuing a large number of
324 * async reads may effect performance, and the earlier
325 * the indirect blocks are prefetched the less likely
326 * they are to still be resident in the ARC when needed.
327 * Therefore, prefetching indirect blocks is limited to
328 * zfs_traverse_indirect_prefetch_limit=32 blocks by
331 * pidx: Index for which next prefetch to be issued.
332 * ptidx: Index at which next prefetch to be triggered.
336 prefetchlimit = zfs_traverse_indirect_prefetch_limit;
337 for (i = 0; i < epb; i++) {
338 if (prefetchlimit && i == ptidx) {
339 ASSERT3S(ptidx, <=, pidx);
340 for (uint32_t prefetched = 0; pidx < epb &&
341 prefetched < prefetchlimit; pidx++) {
342 SET_BOOKMARK(czb, zb->zb_objset,
343 zb->zb_object, zb->zb_level - 1,
344 zb->zb_blkid * epb + pidx);
345 if (traverse_prefetch_metadata(td,
346 &((blkptr_t *)buf->b_data)[pidx],
350 MAX(prefetchlimit / 2, 1))
356 /* recursively visitbp() blocks below this */
357 SET_BOOKMARK(czb, zb->zb_objset, zb->zb_object,
359 zb->zb_blkid * epb + i);
360 err = traverse_visitbp(td, dnp,
361 &((blkptr_t *)buf->b_data)[i], czb);
366 kmem_free(czb, sizeof (zbookmark_phys_t));
368 } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) {
369 uint32_t flags = ARC_FLAG_WAIT;
370 uint32_t zio_flags = ZIO_FLAG_CANFAIL;
372 int32_t epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT;
373 dnode_phys_t *child_dnp;
376 * dnode blocks might have their bonus buffers encrypted, so
377 * we must be careful to honor TRAVERSE_NO_DECRYPT
379 if ((td->td_flags & TRAVERSE_NO_DECRYPT) && BP_IS_PROTECTED(bp))
380 zio_flags |= ZIO_FLAG_RAW;
382 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf,
383 ZIO_PRIORITY_ASYNC_READ, zio_flags, &flags, zb);
387 child_dnp = buf->b_data;
389 for (i = 0; i < epb; i += child_dnp[i].dn_extra_slots + 1) {
390 prefetch_dnode_metadata(td, &child_dnp[i],
391 zb->zb_objset, zb->zb_blkid * epb + i);
394 /* recursively visitbp() blocks below this */
395 for (i = 0; i < epb; i += child_dnp[i].dn_extra_slots + 1) {
396 err = traverse_dnode(td, bp, &child_dnp[i],
397 zb->zb_objset, zb->zb_blkid * epb + i);
401 } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) {
402 uint32_t zio_flags = ZIO_FLAG_CANFAIL;
403 arc_flags_t flags = ARC_FLAG_WAIT;
406 if ((td->td_flags & TRAVERSE_NO_DECRYPT) && BP_IS_PROTECTED(bp))
407 zio_flags |= ZIO_FLAG_RAW;
409 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf,
410 ZIO_PRIORITY_ASYNC_READ, zio_flags, &flags, zb);
415 prefetch_dnode_metadata(td, &osp->os_meta_dnode, zb->zb_objset,
416 DMU_META_DNODE_OBJECT);
418 * See the block comment above for the goal of this variable.
419 * If the maxblkid of the meta-dnode is 0, then we know that
420 * we've never had more than DNODES_PER_BLOCK objects in the
421 * dataset, which means we can't have reused any object ids.
423 if (osp->os_meta_dnode.dn_maxblkid == 0)
424 td->td_realloc_possible = B_FALSE;
426 if (OBJSET_BUF_HAS_USERUSED(buf)) {
427 if (OBJSET_BUF_HAS_PROJECTUSED(buf))
428 prefetch_dnode_metadata(td,
429 &osp->os_projectused_dnode,
430 zb->zb_objset, DMU_PROJECTUSED_OBJECT);
431 prefetch_dnode_metadata(td, &osp->os_groupused_dnode,
432 zb->zb_objset, DMU_GROUPUSED_OBJECT);
433 prefetch_dnode_metadata(td, &osp->os_userused_dnode,
434 zb->zb_objset, DMU_USERUSED_OBJECT);
437 err = traverse_dnode(td, bp, &osp->os_meta_dnode, zb->zb_objset,
438 DMU_META_DNODE_OBJECT);
439 if (err == 0 && OBJSET_BUF_HAS_USERUSED(buf)) {
440 if (OBJSET_BUF_HAS_PROJECTUSED(buf))
441 err = traverse_dnode(td, bp,
442 &osp->os_projectused_dnode, zb->zb_objset,
443 DMU_PROJECTUSED_OBJECT);
445 err = traverse_dnode(td, bp,
446 &osp->os_groupused_dnode, zb->zb_objset,
447 DMU_GROUPUSED_OBJECT);
449 err = traverse_dnode(td, bp,
450 &osp->os_userused_dnode, zb->zb_objset,
451 DMU_USERUSED_OBJECT);
456 arc_buf_destroy(buf, &buf);
459 if (err == 0 && (td->td_flags & TRAVERSE_POST))
460 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg);
462 if ((td->td_flags & TRAVERSE_HARD) && (err == EIO || err == ECKSUM)) {
464 * Ignore this disk error as requested by the HARD flag,
465 * and continue traversal.
471 * If we are stopping here, set td_resume.
473 if (td->td_resume != NULL && err != 0 && !td->td_paused) {
474 td->td_resume->zb_objset = zb->zb_objset;
475 td->td_resume->zb_object = zb->zb_object;
476 td->td_resume->zb_level = 0;
478 * If we have stopped on an indirect block (e.g. due to
479 * i/o error), we have not visited anything below it.
480 * Set the bookmark to the first level-0 block that we need
481 * to visit. This way, the resuming code does not need to
482 * deal with resuming from indirect blocks.
484 * Note, if zb_level <= 0, dnp may be NULL, so we don't want
487 td->td_resume->zb_blkid = zb->zb_blkid;
488 if (zb->zb_level > 0) {
489 td->td_resume->zb_blkid <<= zb->zb_level *
490 (dnp->dn_indblkshift - SPA_BLKPTRSHIFT);
492 td->td_paused = B_TRUE;
499 prefetch_dnode_metadata(traverse_data_t *td, const dnode_phys_t *dnp,
500 uint64_t objset, uint64_t object)
503 zbookmark_phys_t czb;
505 for (j = 0; j < dnp->dn_nblkptr; j++) {
506 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j);
507 traverse_prefetch_metadata(td, &dnp->dn_blkptr[j], &czb);
510 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
511 SET_BOOKMARK(&czb, objset, object, 0, DMU_SPILL_BLKID);
512 traverse_prefetch_metadata(td, DN_SPILL_BLKPTR(dnp), &czb);
517 traverse_dnode(traverse_data_t *td, const blkptr_t *bp, const dnode_phys_t *dnp,
518 uint64_t objset, uint64_t object)
521 zbookmark_phys_t czb;
523 if (object != DMU_META_DNODE_OBJECT && td->td_resume != NULL &&
524 object < td->td_resume->zb_object)
527 if (td->td_flags & TRAVERSE_PRE) {
528 SET_BOOKMARK(&czb, objset, object, ZB_DNODE_LEVEL,
530 err = td->td_func(td->td_spa, NULL, bp, &czb, dnp,
532 if (err == TRAVERSE_VISIT_NO_CHILDREN)
538 for (j = 0; j < dnp->dn_nblkptr; j++) {
539 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j);
540 err = traverse_visitbp(td, dnp, &dnp->dn_blkptr[j], &czb);
545 if (err == 0 && (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR)) {
546 SET_BOOKMARK(&czb, objset, object, 0, DMU_SPILL_BLKID);
547 err = traverse_visitbp(td, dnp, DN_SPILL_BLKPTR(dnp), &czb);
550 if (err == 0 && (td->td_flags & TRAVERSE_POST)) {
551 SET_BOOKMARK(&czb, objset, object, ZB_DNODE_LEVEL,
553 err = td->td_func(td->td_spa, NULL, bp, &czb, dnp,
555 if (err == TRAVERSE_VISIT_NO_CHILDREN)
564 traverse_prefetcher(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
565 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
567 (void) zilog, (void) dnp;
568 prefetch_data_t *pfd = arg;
569 int zio_flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE;
570 arc_flags_t aflags = ARC_FLAG_NOWAIT | ARC_FLAG_PREFETCH |
571 ARC_FLAG_PRESCIENT_PREFETCH;
573 ASSERT(pfd->pd_bytes_fetched >= 0);
574 if (zb->zb_level == ZB_DNODE_LEVEL)
577 return (SET_ERROR(EINTR));
579 if (!prefetch_needed(pfd, bp))
582 mutex_enter(&pfd->pd_mtx);
583 while (!pfd->pd_cancel && pfd->pd_bytes_fetched >= zfs_pd_bytes_max)
584 cv_wait_sig(&pfd->pd_cv, &pfd->pd_mtx);
585 pfd->pd_bytes_fetched += BP_GET_LSIZE(bp);
586 cv_broadcast(&pfd->pd_cv);
587 mutex_exit(&pfd->pd_mtx);
589 if ((pfd->pd_flags & TRAVERSE_NO_DECRYPT) && BP_IS_PROTECTED(bp))
590 zio_flags |= ZIO_FLAG_RAW;
592 (void) arc_read(NULL, spa, bp, NULL, NULL, ZIO_PRIORITY_ASYNC_READ,
593 zio_flags, &aflags, zb);
599 traverse_prefetch_thread(void *arg)
601 traverse_data_t *td_main = arg;
602 traverse_data_t td = *td_main;
603 zbookmark_phys_t czb;
604 fstrans_cookie_t cookie = spl_fstrans_mark();
606 td.td_func = traverse_prefetcher;
607 td.td_arg = td_main->td_pfd;
609 td.td_resume = &td_main->td_pfd->pd_resume;
611 SET_BOOKMARK(&czb, td.td_objset,
612 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
613 (void) traverse_visitbp(&td, NULL, td.td_rootbp, &czb);
615 mutex_enter(&td_main->td_pfd->pd_mtx);
616 td_main->td_pfd->pd_exited = B_TRUE;
617 cv_broadcast(&td_main->td_pfd->pd_cv);
618 mutex_exit(&td_main->td_pfd->pd_mtx);
619 spl_fstrans_unmark(cookie);
623 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are
624 * in syncing context).
627 traverse_impl(spa_t *spa, dsl_dataset_t *ds, uint64_t objset, blkptr_t *rootbp,
628 uint64_t txg_start, zbookmark_phys_t *resume, int flags,
629 blkptr_cb_t func, void *arg)
633 zbookmark_phys_t *czb;
636 ASSERT(ds == NULL || objset == ds->ds_object);
637 ASSERT(!(flags & TRAVERSE_PRE) || !(flags & TRAVERSE_POST));
639 td = kmem_alloc(sizeof (traverse_data_t), KM_SLEEP);
640 pd = kmem_zalloc(sizeof (prefetch_data_t), KM_SLEEP);
641 czb = kmem_alloc(sizeof (zbookmark_phys_t), KM_SLEEP);
644 td->td_objset = objset;
645 td->td_rootbp = rootbp;
646 td->td_min_txg = txg_start;
647 td->td_resume = resume;
651 td->td_flags = flags;
652 td->td_paused = B_FALSE;
653 td->td_realloc_possible = (txg_start == 0 ? B_FALSE : B_TRUE);
655 if (spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) {
656 VERIFY(spa_feature_enabled_txg(spa,
657 SPA_FEATURE_HOLE_BIRTH, &td->td_hole_birth_enabled_txg));
659 td->td_hole_birth_enabled_txg = UINT64_MAX;
662 pd->pd_flags = flags;
664 pd->pd_resume = *resume;
665 mutex_init(&pd->pd_mtx, NULL, MUTEX_DEFAULT, NULL);
666 cv_init(&pd->pd_cv, NULL, CV_DEFAULT, NULL);
668 SET_BOOKMARK(czb, td->td_objset,
669 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
671 /* See comment on ZIL traversal in dsl_scan_visitds. */
672 if (ds != NULL && !ds->ds_is_snapshot && !BP_IS_HOLE(rootbp)) {
673 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL;
674 uint32_t flags = ARC_FLAG_WAIT;
677 ASSERT(!BP_IS_REDACTED(rootbp));
679 if ((td->td_flags & TRAVERSE_NO_DECRYPT) &&
680 BP_IS_PROTECTED(rootbp))
681 zio_flags |= ZIO_FLAG_RAW;
683 err = arc_read(NULL, td->td_spa, rootbp, arc_getbuf_func,
684 &buf, ZIO_PRIORITY_ASYNC_READ, zio_flags, &flags, czb);
687 * If both TRAVERSE_HARD and TRAVERSE_PRE are set,
688 * continue to visitbp so that td_func can be called
689 * in pre stage, and err will reset to zero.
691 if (!(td->td_flags & TRAVERSE_HARD) ||
692 !(td->td_flags & TRAVERSE_PRE))
696 traverse_zil(td, &osp->os_zil_header);
697 arc_buf_destroy(buf, &buf);
701 if (!(flags & TRAVERSE_PREFETCH_DATA) ||
702 taskq_dispatch(spa->spa_prefetch_taskq, traverse_prefetch_thread,
703 td, TQ_NOQUEUE) == TASKQID_INVALID)
704 pd->pd_exited = B_TRUE;
706 err = traverse_visitbp(td, NULL, rootbp, czb);
708 mutex_enter(&pd->pd_mtx);
709 pd->pd_cancel = B_TRUE;
710 cv_broadcast(&pd->pd_cv);
711 while (!pd->pd_exited)
712 cv_wait_sig(&pd->pd_cv, &pd->pd_mtx);
713 mutex_exit(&pd->pd_mtx);
715 mutex_destroy(&pd->pd_mtx);
716 cv_destroy(&pd->pd_cv);
718 kmem_free(czb, sizeof (zbookmark_phys_t));
719 kmem_free(pd, sizeof (struct prefetch_data));
720 kmem_free(td, sizeof (struct traverse_data));
726 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are
727 * in syncing context).
730 traverse_dataset_resume(dsl_dataset_t *ds, uint64_t txg_start,
731 zbookmark_phys_t *resume,
732 int flags, blkptr_cb_t func, void *arg)
734 return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds, ds->ds_object,
735 &dsl_dataset_phys(ds)->ds_bp, txg_start, resume, flags, func, arg));
739 traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start,
740 int flags, blkptr_cb_t func, void *arg)
742 return (traverse_dataset_resume(ds, txg_start, NULL, flags, func, arg));
746 traverse_dataset_destroyed(spa_t *spa, blkptr_t *blkptr,
747 uint64_t txg_start, zbookmark_phys_t *resume, int flags,
748 blkptr_cb_t func, void *arg)
750 return (traverse_impl(spa, NULL, ZB_DESTROYED_OBJSET,
751 blkptr, txg_start, resume, flags, func, arg));
755 * NB: pool must not be changing on-disk (eg, from zdb or sync context).
758 traverse_pool(spa_t *spa, uint64_t txg_start, int flags,
759 blkptr_cb_t func, void *arg)
762 dsl_pool_t *dp = spa_get_dsl(spa);
763 objset_t *mos = dp->dp_meta_objset;
764 boolean_t hard = (flags & TRAVERSE_HARD);
767 err = traverse_impl(spa, NULL, 0, spa_get_rootblkptr(spa),
768 txg_start, NULL, flags, func, arg);
772 /* visit each dataset */
773 for (uint64_t obj = 1; err == 0;
774 err = dmu_object_next(mos, &obj, B_FALSE, txg_start)) {
775 dmu_object_info_t doi;
777 err = dmu_object_info(mos, obj, &doi);
784 if (doi.doi_bonus_type == DMU_OT_DSL_DATASET) {
786 uint64_t txg = txg_start;
788 dsl_pool_config_enter(dp, FTAG);
789 err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
790 dsl_pool_config_exit(dp, FTAG);
796 if (dsl_dataset_phys(ds)->ds_prev_snap_txg > txg)
797 txg = dsl_dataset_phys(ds)->ds_prev_snap_txg;
798 err = traverse_dataset(ds, txg, flags, func, arg);
799 dsl_dataset_rele(ds, FTAG);
809 EXPORT_SYMBOL(traverse_dataset);
810 EXPORT_SYMBOL(traverse_pool);
812 ZFS_MODULE_PARAM(zfs, zfs_, pd_bytes_max, INT, ZMOD_RW,
813 "Max number of bytes to prefetch");
815 ZFS_MODULE_PARAM(zfs, zfs_, traverse_indirect_prefetch_limit, INT, ZMOD_RW,
816 "Traverse prefetch number of blocks pointed by indirect block");
819 module_param_named(ignore_hole_birth, send_holes_without_birth_time, int, 0644);
820 MODULE_PARM_DESC(ignore_hole_birth,
821 "Alias for send_holes_without_birth_time");
825 ZFS_MODULE_PARAM(zfs, , send_holes_without_birth_time, INT, ZMOD_RW,
826 "Ignore hole_birth txg for zfs send");