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) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
24 * Copyright 2016 Gary Mills
27 #include <sys/dsl_scan.h>
28 #include <sys/dsl_pool.h>
29 #include <sys/dsl_dataset.h>
30 #include <sys/dsl_prop.h>
31 #include <sys/dsl_dir.h>
32 #include <sys/dsl_synctask.h>
33 #include <sys/dnode.h>
34 #include <sys/dmu_tx.h>
35 #include <sys/dmu_objset.h>
39 #include <sys/zfs_context.h>
40 #include <sys/fs/zfs.h>
41 #include <sys/zfs_znode.h>
42 #include <sys/spa_impl.h>
43 #include <sys/vdev_impl.h>
44 #include <sys/zil_impl.h>
45 #include <sys/zio_checksum.h>
48 #include <sys/sa_impl.h>
49 #include <sys/zfeature.h>
51 #include <sys/zfs_vfsops.h>
54 typedef int (scan_cb_t
)(dsl_pool_t
*, const blkptr_t
*,
55 const zbookmark_phys_t
*);
57 static scan_cb_t dsl_scan_scrub_cb
;
58 static void dsl_scan_cancel_sync(void *, dmu_tx_t
*);
59 static void dsl_scan_sync_state(dsl_scan_t
*, dmu_tx_t
*);
60 static boolean_t
dsl_scan_restarting(dsl_scan_t
*, dmu_tx_t
*);
62 int zfs_top_maxinflight
= 32; /* maximum I/Os per top-level */
63 int zfs_resilver_delay
= 2; /* number of ticks to delay resilver */
64 int zfs_scrub_delay
= 4; /* number of ticks to delay scrub */
65 int zfs_scan_idle
= 50; /* idle window in clock ticks */
67 int zfs_scan_min_time_ms
= 1000; /* min millisecs to scrub per txg */
68 int zfs_free_min_time_ms
= 1000; /* min millisecs to free per txg */
69 int zfs_resilver_min_time_ms
= 3000; /* min millisecs to resilver per txg */
70 boolean_t zfs_no_scrub_io
= B_FALSE
; /* set to disable scrub i/o */
71 boolean_t zfs_no_scrub_prefetch
= B_FALSE
; /* set to disable scrub prefetch */
72 enum ddt_class zfs_scrub_ddt_class_max
= DDT_CLASS_DUPLICATE
;
73 int dsl_scan_delay_completion
= B_FALSE
; /* set to delay scan completion */
74 /* max number of blocks to free in a single TXG */
75 uint64_t zfs_free_max_blocks
= UINT64_MAX
;
77 #define DSL_SCAN_IS_SCRUB_RESILVER(scn) \
78 ((scn)->scn_phys.scn_func == POOL_SCAN_SCRUB || \
79 (scn)->scn_phys.scn_func == POOL_SCAN_RESILVER)
81 extern int zfs_txg_timeout
;
84 * Enable/disable the processing of the free_bpobj object.
86 boolean_t zfs_free_bpobj_enabled
= B_TRUE
;
88 /* the order has to match pool_scan_type */
89 static scan_cb_t
*scan_funcs
[POOL_SCAN_FUNCS
] = {
91 dsl_scan_scrub_cb
, /* POOL_SCAN_SCRUB */
92 dsl_scan_scrub_cb
, /* POOL_SCAN_RESILVER */
96 dsl_scan_init(dsl_pool_t
*dp
, uint64_t txg
)
100 spa_t
*spa
= dp
->dp_spa
;
103 scn
= dp
->dp_scan
= kmem_zalloc(sizeof (dsl_scan_t
), KM_SLEEP
);
107 * It's possible that we're resuming a scan after a reboot so
108 * make sure that the scan_async_destroying flag is initialized
111 ASSERT(!scn
->scn_async_destroying
);
112 scn
->scn_async_destroying
= spa_feature_is_active(dp
->dp_spa
,
113 SPA_FEATURE_ASYNC_DESTROY
);
115 err
= zap_lookup(dp
->dp_meta_objset
, DMU_POOL_DIRECTORY_OBJECT
,
116 "scrub_func", sizeof (uint64_t), 1, &f
);
119 * There was an old-style scrub in progress. Restart a
120 * new-style scrub from the beginning.
122 scn
->scn_restart_txg
= txg
;
123 zfs_dbgmsg("old-style scrub was in progress; "
124 "restarting new-style scrub in txg %llu",
125 scn
->scn_restart_txg
);
128 * Load the queue obj from the old location so that it
129 * can be freed by dsl_scan_done().
131 (void) zap_lookup(dp
->dp_meta_objset
, DMU_POOL_DIRECTORY_OBJECT
,
132 "scrub_queue", sizeof (uint64_t), 1,
133 &scn
->scn_phys
.scn_queue_obj
);
135 err
= zap_lookup(dp
->dp_meta_objset
, DMU_POOL_DIRECTORY_OBJECT
,
136 DMU_POOL_SCAN
, sizeof (uint64_t), SCAN_PHYS_NUMINTS
,
143 if (scn
->scn_phys
.scn_state
== DSS_SCANNING
&&
144 spa_prev_software_version(dp
->dp_spa
) < SPA_VERSION_SCAN
) {
146 * A new-type scrub was in progress on an old
147 * pool, and the pool was accessed by old
148 * software. Restart from the beginning, since
149 * the old software may have changed the pool in
152 scn
->scn_restart_txg
= txg
;
153 zfs_dbgmsg("new-style scrub was modified "
154 "by old software; restarting in txg %llu",
155 scn
->scn_restart_txg
);
159 spa_scan_stat_init(spa
);
164 dsl_scan_fini(dsl_pool_t
*dp
)
167 kmem_free(dp
->dp_scan
, sizeof (dsl_scan_t
));
174 dsl_scan_setup_check(void *arg
, dmu_tx_t
*tx
)
176 dsl_scan_t
*scn
= dmu_tx_pool(tx
)->dp_scan
;
178 if (scn
->scn_phys
.scn_state
== DSS_SCANNING
)
179 return (SET_ERROR(EBUSY
));
185 dsl_scan_setup_sync(void *arg
, dmu_tx_t
*tx
)
187 dsl_scan_t
*scn
= dmu_tx_pool(tx
)->dp_scan
;
188 pool_scan_func_t
*funcp
= arg
;
189 dmu_object_type_t ot
= 0;
190 dsl_pool_t
*dp
= scn
->scn_dp
;
191 spa_t
*spa
= dp
->dp_spa
;
193 ASSERT(scn
->scn_phys
.scn_state
!= DSS_SCANNING
);
194 ASSERT(*funcp
> POOL_SCAN_NONE
&& *funcp
< POOL_SCAN_FUNCS
);
195 bzero(&scn
->scn_phys
, sizeof (scn
->scn_phys
));
196 scn
->scn_phys
.scn_func
= *funcp
;
197 scn
->scn_phys
.scn_state
= DSS_SCANNING
;
198 scn
->scn_phys
.scn_min_txg
= 0;
199 scn
->scn_phys
.scn_max_txg
= tx
->tx_txg
;
200 scn
->scn_phys
.scn_ddt_class_max
= DDT_CLASSES
- 1; /* the entire DDT */
201 scn
->scn_phys
.scn_start_time
= gethrestime_sec();
202 scn
->scn_phys
.scn_errors
= 0;
203 scn
->scn_phys
.scn_to_examine
= spa
->spa_root_vdev
->vdev_stat
.vs_alloc
;
204 scn
->scn_restart_txg
= 0;
205 scn
->scn_done_txg
= 0;
206 spa_scan_stat_init(spa
);
208 if (DSL_SCAN_IS_SCRUB_RESILVER(scn
)) {
209 scn
->scn_phys
.scn_ddt_class_max
= zfs_scrub_ddt_class_max
;
211 /* rewrite all disk labels */
212 vdev_config_dirty(spa
->spa_root_vdev
);
214 if (vdev_resilver_needed(spa
->spa_root_vdev
,
215 &scn
->scn_phys
.scn_min_txg
, &scn
->scn_phys
.scn_max_txg
)) {
216 spa_event_notify(spa
, NULL
, ESC_ZFS_RESILVER_START
);
218 spa_event_notify(spa
, NULL
, ESC_ZFS_SCRUB_START
);
221 spa
->spa_scrub_started
= B_TRUE
;
223 * If this is an incremental scrub, limit the DDT scrub phase
224 * to just the auto-ditto class (for correctness); the rest
225 * of the scrub should go faster using top-down pruning.
227 if (scn
->scn_phys
.scn_min_txg
> TXG_INITIAL
)
228 scn
->scn_phys
.scn_ddt_class_max
= DDT_CLASS_DITTO
;
232 /* back to the generic stuff */
234 if (dp
->dp_blkstats
== NULL
) {
236 kmem_alloc(sizeof (zfs_all_blkstats_t
), KM_SLEEP
);
238 bzero(dp
->dp_blkstats
, sizeof (zfs_all_blkstats_t
));
240 if (spa_version(spa
) < SPA_VERSION_DSL_SCRUB
)
241 ot
= DMU_OT_ZAP_OTHER
;
243 scn
->scn_phys
.scn_queue_obj
= zap_create(dp
->dp_meta_objset
,
244 ot
? ot
: DMU_OT_SCAN_QUEUE
, DMU_OT_NONE
, 0, tx
);
246 dsl_scan_sync_state(scn
, tx
);
248 spa_history_log_internal(spa
, "scan setup", tx
,
249 "func=%u mintxg=%llu maxtxg=%llu",
250 *funcp
, scn
->scn_phys
.scn_min_txg
, scn
->scn_phys
.scn_max_txg
);
255 dsl_scan_done(dsl_scan_t
*scn
, boolean_t complete
, dmu_tx_t
*tx
)
257 static const char *old_names
[] = {
259 "scrub_ddt_bookmark",
260 "scrub_ddt_class_max",
269 dsl_pool_t
*dp
= scn
->scn_dp
;
270 spa_t
*spa
= dp
->dp_spa
;
273 /* Remove any remnants of an old-style scrub. */
274 for (i
= 0; old_names
[i
]; i
++) {
275 (void) zap_remove(dp
->dp_meta_objset
,
276 DMU_POOL_DIRECTORY_OBJECT
, old_names
[i
], tx
);
279 if (scn
->scn_phys
.scn_queue_obj
!= 0) {
280 VERIFY(0 == dmu_object_free(dp
->dp_meta_objset
,
281 scn
->scn_phys
.scn_queue_obj
, tx
));
282 scn
->scn_phys
.scn_queue_obj
= 0;
286 * If we were "restarted" from a stopped state, don't bother
287 * with anything else.
289 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
293 scn
->scn_phys
.scn_state
= DSS_FINISHED
;
295 scn
->scn_phys
.scn_state
= DSS_CANCELED
;
297 if (dsl_scan_restarting(scn
, tx
))
298 spa_history_log_internal(spa
, "scan aborted, restarting", tx
,
299 "errors=%llu", spa_get_errlog_size(spa
));
301 spa_history_log_internal(spa
, "scan cancelled", tx
,
302 "errors=%llu", spa_get_errlog_size(spa
));
304 spa_history_log_internal(spa
, "scan done", tx
,
305 "errors=%llu", spa_get_errlog_size(spa
));
307 if (DSL_SCAN_IS_SCRUB_RESILVER(scn
)) {
308 mutex_enter(&spa
->spa_scrub_lock
);
309 while (spa
->spa_scrub_inflight
> 0) {
310 cv_wait(&spa
->spa_scrub_io_cv
,
311 &spa
->spa_scrub_lock
);
313 mutex_exit(&spa
->spa_scrub_lock
);
314 spa
->spa_scrub_started
= B_FALSE
;
315 spa
->spa_scrub_active
= B_FALSE
;
318 * If the scrub/resilver completed, update all DTLs to
319 * reflect this. Whether it succeeded or not, vacate
320 * all temporary scrub DTLs.
322 vdev_dtl_reassess(spa
->spa_root_vdev
, tx
->tx_txg
,
323 complete
? scn
->scn_phys
.scn_max_txg
: 0, B_TRUE
);
325 spa_event_notify(spa
, NULL
, scn
->scn_phys
.scn_min_txg
?
326 ESC_ZFS_RESILVER_FINISH
: ESC_ZFS_SCRUB_FINISH
);
328 spa_errlog_rotate(spa
);
331 * We may have finished replacing a device.
332 * Let the async thread assess this and handle the detach.
334 spa_async_request(spa
, SPA_ASYNC_RESILVER_DONE
);
337 scn
->scn_phys
.scn_end_time
= gethrestime_sec();
342 dsl_scan_cancel_check(void *arg
, dmu_tx_t
*tx
)
344 dsl_scan_t
*scn
= dmu_tx_pool(tx
)->dp_scan
;
346 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
347 return (SET_ERROR(ENOENT
));
353 dsl_scan_cancel_sync(void *arg
, dmu_tx_t
*tx
)
355 dsl_scan_t
*scn
= dmu_tx_pool(tx
)->dp_scan
;
357 dsl_scan_done(scn
, B_FALSE
, tx
);
358 dsl_scan_sync_state(scn
, tx
);
362 dsl_scan_cancel(dsl_pool_t
*dp
)
364 return (dsl_sync_task(spa_name(dp
->dp_spa
), dsl_scan_cancel_check
,
365 dsl_scan_cancel_sync
, NULL
, 3, ZFS_SPACE_CHECK_RESERVED
));
368 static void dsl_scan_visitbp(blkptr_t
*bp
, const zbookmark_phys_t
*zb
,
369 dnode_phys_t
*dnp
, dsl_dataset_t
*ds
, dsl_scan_t
*scn
,
370 dmu_objset_type_t ostype
, dmu_tx_t
*tx
);
371 static void dsl_scan_visitdnode(dsl_scan_t
*, dsl_dataset_t
*ds
,
372 dmu_objset_type_t ostype
,
373 dnode_phys_t
*dnp
, uint64_t object
, dmu_tx_t
*tx
);
376 dsl_free(dsl_pool_t
*dp
, uint64_t txg
, const blkptr_t
*bp
)
378 zio_free(dp
->dp_spa
, txg
, bp
);
382 dsl_free_sync(zio_t
*pio
, dsl_pool_t
*dp
, uint64_t txg
, const blkptr_t
*bpp
)
384 ASSERT(dsl_pool_sync_context(dp
));
385 zio_nowait(zio_free_sync(pio
, dp
->dp_spa
, txg
, bpp
, pio
->io_flags
));
389 dsl_scan_ds_maxtxg(dsl_dataset_t
*ds
)
391 uint64_t smt
= ds
->ds_dir
->dd_pool
->dp_scan
->scn_phys
.scn_max_txg
;
392 if (ds
->ds_is_snapshot
)
393 return (MIN(smt
, dsl_dataset_phys(ds
)->ds_creation_txg
));
398 dsl_scan_sync_state(dsl_scan_t
*scn
, dmu_tx_t
*tx
)
400 VERIFY0(zap_update(scn
->scn_dp
->dp_meta_objset
,
401 DMU_POOL_DIRECTORY_OBJECT
,
402 DMU_POOL_SCAN
, sizeof (uint64_t), SCAN_PHYS_NUMINTS
,
403 &scn
->scn_phys
, tx
));
406 extern int zfs_vdev_async_write_active_min_dirty_percent
;
409 dsl_scan_check_pause(dsl_scan_t
*scn
, const zbookmark_phys_t
*zb
)
411 /* we never skip user/group accounting objects */
412 if (zb
&& (int64_t)zb
->zb_object
< 0)
415 if (scn
->scn_pausing
)
416 return (B_TRUE
); /* we're already pausing */
418 if (!ZB_IS_ZERO(&scn
->scn_phys
.scn_bookmark
))
419 return (B_FALSE
); /* we're resuming */
421 /* We only know how to resume from level-0 blocks. */
422 if (zb
&& zb
->zb_level
!= 0)
427 * - we have scanned for the maximum time: an entire txg
428 * timeout (default 5 sec)
430 * - we have scanned for at least the minimum time (default 1 sec
431 * for scrub, 3 sec for resilver), and either we have sufficient
432 * dirty data that we are starting to write more quickly
433 * (default 30%), or someone is explicitly waiting for this txg
436 * - the spa is shutting down because this pool is being exported
437 * or the machine is rebooting.
439 int mintime
= (scn
->scn_phys
.scn_func
== POOL_SCAN_RESILVER
) ?
440 zfs_resilver_min_time_ms
: zfs_scan_min_time_ms
;
441 uint64_t elapsed_nanosecs
= gethrtime() - scn
->scn_sync_start_time
;
442 int dirty_pct
= scn
->scn_dp
->dp_dirty_total
* 100 / zfs_dirty_data_max
;
443 if (elapsed_nanosecs
/ NANOSEC
>= zfs_txg_timeout
||
444 (NSEC2MSEC(elapsed_nanosecs
) > mintime
&&
445 (txg_sync_waiting(scn
->scn_dp
) ||
446 dirty_pct
>= zfs_vdev_async_write_active_min_dirty_percent
)) ||
447 spa_shutting_down(scn
->scn_dp
->dp_spa
)) {
449 dprintf("pausing at bookmark %llx/%llx/%llx/%llx\n",
450 (longlong_t
)zb
->zb_objset
,
451 (longlong_t
)zb
->zb_object
,
452 (longlong_t
)zb
->zb_level
,
453 (longlong_t
)zb
->zb_blkid
);
454 scn
->scn_phys
.scn_bookmark
= *zb
;
456 dprintf("pausing at DDT bookmark %llx/%llx/%llx/%llx\n",
457 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_class
,
458 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_type
,
459 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_checksum
,
460 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_cursor
);
461 scn
->scn_pausing
= B_TRUE
;
467 typedef struct zil_scan_arg
{
469 zil_header_t
*zsa_zh
;
474 dsl_scan_zil_block(zilog_t
*zilog
, blkptr_t
*bp
, void *arg
, uint64_t claim_txg
)
476 zil_scan_arg_t
*zsa
= arg
;
477 dsl_pool_t
*dp
= zsa
->zsa_dp
;
478 dsl_scan_t
*scn
= dp
->dp_scan
;
479 zil_header_t
*zh
= zsa
->zsa_zh
;
482 if (BP_IS_HOLE(bp
) || bp
->blk_birth
<= scn
->scn_phys
.scn_cur_min_txg
)
486 * One block ("stubby") can be allocated a long time ago; we
487 * want to visit that one because it has been allocated
488 * (on-disk) even if it hasn't been claimed (even though for
489 * scrub there's nothing to do to it).
491 if (claim_txg
== 0 && bp
->blk_birth
>= spa_first_txg(dp
->dp_spa
))
494 SET_BOOKMARK(&zb
, zh
->zh_log
.blk_cksum
.zc_word
[ZIL_ZC_OBJSET
],
495 ZB_ZIL_OBJECT
, ZB_ZIL_LEVEL
, bp
->blk_cksum
.zc_word
[ZIL_ZC_SEQ
]);
497 VERIFY(0 == scan_funcs
[scn
->scn_phys
.scn_func
](dp
, bp
, &zb
));
503 dsl_scan_zil_record(zilog_t
*zilog
, lr_t
*lrc
, void *arg
, uint64_t claim_txg
)
505 if (lrc
->lrc_txtype
== TX_WRITE
) {
506 zil_scan_arg_t
*zsa
= arg
;
507 dsl_pool_t
*dp
= zsa
->zsa_dp
;
508 dsl_scan_t
*scn
= dp
->dp_scan
;
509 zil_header_t
*zh
= zsa
->zsa_zh
;
510 lr_write_t
*lr
= (lr_write_t
*)lrc
;
511 blkptr_t
*bp
= &lr
->lr_blkptr
;
514 if (BP_IS_HOLE(bp
) ||
515 bp
->blk_birth
<= scn
->scn_phys
.scn_cur_min_txg
)
519 * birth can be < claim_txg if this record's txg is
520 * already txg sync'ed (but this log block contains
521 * other records that are not synced)
523 if (claim_txg
== 0 || bp
->blk_birth
< claim_txg
)
526 SET_BOOKMARK(&zb
, zh
->zh_log
.blk_cksum
.zc_word
[ZIL_ZC_OBJSET
],
527 lr
->lr_foid
, ZB_ZIL_LEVEL
,
528 lr
->lr_offset
/ BP_GET_LSIZE(bp
));
530 VERIFY(0 == scan_funcs
[scn
->scn_phys
.scn_func
](dp
, bp
, &zb
));
536 dsl_scan_zil(dsl_pool_t
*dp
, zil_header_t
*zh
)
538 uint64_t claim_txg
= zh
->zh_claim_txg
;
539 zil_scan_arg_t zsa
= { dp
, zh
};
543 * We only want to visit blocks that have been claimed but not yet
544 * replayed (or, in read-only mode, blocks that *would* be claimed).
546 if (claim_txg
== 0 && spa_writeable(dp
->dp_spa
))
549 zilog
= zil_alloc(dp
->dp_meta_objset
, zh
);
551 (void) zil_parse(zilog
, dsl_scan_zil_block
, dsl_scan_zil_record
, &zsa
,
559 dsl_scan_prefetch(dsl_scan_t
*scn
, arc_buf_t
*buf
, blkptr_t
*bp
,
560 uint64_t objset
, uint64_t object
, uint64_t blkid
)
562 zbookmark_phys_t czb
;
563 arc_flags_t flags
= ARC_FLAG_NOWAIT
| ARC_FLAG_PREFETCH
;
565 if (zfs_no_scrub_prefetch
)
568 if (BP_IS_HOLE(bp
) || bp
->blk_birth
<= scn
->scn_phys
.scn_min_txg
||
569 (BP_GET_LEVEL(bp
) == 0 && BP_GET_TYPE(bp
) != DMU_OT_DNODE
))
572 SET_BOOKMARK(&czb
, objset
, object
, BP_GET_LEVEL(bp
), blkid
);
574 (void) arc_read(scn
->scn_zio_root
, scn
->scn_dp
->dp_spa
, bp
,
575 NULL
, NULL
, ZIO_PRIORITY_ASYNC_READ
,
576 ZIO_FLAG_CANFAIL
| ZIO_FLAG_SCAN_THREAD
, &flags
, &czb
);
580 dsl_scan_check_resume(dsl_scan_t
*scn
, const dnode_phys_t
*dnp
,
581 const zbookmark_phys_t
*zb
)
584 * We never skip over user/group accounting objects (obj<0)
586 if (!ZB_IS_ZERO(&scn
->scn_phys
.scn_bookmark
) &&
587 (int64_t)zb
->zb_object
>= 0) {
589 * If we already visited this bp & everything below (in
590 * a prior txg sync), don't bother doing it again.
592 if (zbookmark_subtree_completed(dnp
, zb
,
593 &scn
->scn_phys
.scn_bookmark
))
597 * If we found the block we're trying to resume from, or
598 * we went past it to a different object, zero it out to
599 * indicate that it's OK to start checking for pausing
602 if (bcmp(zb
, &scn
->scn_phys
.scn_bookmark
, sizeof (*zb
)) == 0 ||
603 zb
->zb_object
> scn
->scn_phys
.scn_bookmark
.zb_object
) {
604 dprintf("resuming at %llx/%llx/%llx/%llx\n",
605 (longlong_t
)zb
->zb_objset
,
606 (longlong_t
)zb
->zb_object
,
607 (longlong_t
)zb
->zb_level
,
608 (longlong_t
)zb
->zb_blkid
);
609 bzero(&scn
->scn_phys
.scn_bookmark
, sizeof (*zb
));
616 * Return nonzero on i/o error.
617 * Return new buf to write out in *bufp.
620 dsl_scan_recurse(dsl_scan_t
*scn
, dsl_dataset_t
*ds
, dmu_objset_type_t ostype
,
621 dnode_phys_t
*dnp
, const blkptr_t
*bp
,
622 const zbookmark_phys_t
*zb
, dmu_tx_t
*tx
)
624 dsl_pool_t
*dp
= scn
->scn_dp
;
625 int zio_flags
= ZIO_FLAG_CANFAIL
| ZIO_FLAG_SCAN_THREAD
;
628 if (BP_GET_LEVEL(bp
) > 0) {
629 arc_flags_t flags
= ARC_FLAG_WAIT
;
632 int epb
= BP_GET_LSIZE(bp
) >> SPA_BLKPTRSHIFT
;
635 err
= arc_read(NULL
, dp
->dp_spa
, bp
, arc_getbuf_func
, &buf
,
636 ZIO_PRIORITY_ASYNC_READ
, zio_flags
, &flags
, zb
);
638 scn
->scn_phys
.scn_errors
++;
641 for (i
= 0, cbp
= buf
->b_data
; i
< epb
; i
++, cbp
++) {
642 dsl_scan_prefetch(scn
, buf
, cbp
, zb
->zb_objset
,
643 zb
->zb_object
, zb
->zb_blkid
* epb
+ i
);
645 for (i
= 0, cbp
= buf
->b_data
; i
< epb
; i
++, cbp
++) {
646 zbookmark_phys_t czb
;
648 SET_BOOKMARK(&czb
, zb
->zb_objset
, zb
->zb_object
,
650 zb
->zb_blkid
* epb
+ i
);
651 dsl_scan_visitbp(cbp
, &czb
, dnp
,
652 ds
, scn
, ostype
, tx
);
654 (void) arc_buf_remove_ref(buf
, &buf
);
655 } else if (BP_GET_TYPE(bp
) == DMU_OT_DNODE
) {
656 arc_flags_t flags
= ARC_FLAG_WAIT
;
659 int epb
= BP_GET_LSIZE(bp
) >> DNODE_SHIFT
;
662 err
= arc_read(NULL
, dp
->dp_spa
, bp
, arc_getbuf_func
, &buf
,
663 ZIO_PRIORITY_ASYNC_READ
, zio_flags
, &flags
, zb
);
665 scn
->scn_phys
.scn_errors
++;
668 for (i
= 0, cdnp
= buf
->b_data
; i
< epb
; i
++, cdnp
++) {
669 for (j
= 0; j
< cdnp
->dn_nblkptr
; j
++) {
670 blkptr_t
*cbp
= &cdnp
->dn_blkptr
[j
];
671 dsl_scan_prefetch(scn
, buf
, cbp
,
672 zb
->zb_objset
, zb
->zb_blkid
* epb
+ i
, j
);
675 for (i
= 0, cdnp
= buf
->b_data
; i
< epb
; i
++, cdnp
++) {
676 dsl_scan_visitdnode(scn
, ds
, ostype
,
677 cdnp
, zb
->zb_blkid
* epb
+ i
, tx
);
680 (void) arc_buf_remove_ref(buf
, &buf
);
681 } else if (BP_GET_TYPE(bp
) == DMU_OT_OBJSET
) {
682 arc_flags_t flags
= ARC_FLAG_WAIT
;
686 err
= arc_read(NULL
, dp
->dp_spa
, bp
, arc_getbuf_func
, &buf
,
687 ZIO_PRIORITY_ASYNC_READ
, zio_flags
, &flags
, zb
);
689 scn
->scn_phys
.scn_errors
++;
695 dsl_scan_visitdnode(scn
, ds
, osp
->os_type
,
696 &osp
->os_meta_dnode
, DMU_META_DNODE_OBJECT
, tx
);
698 if (OBJSET_BUF_HAS_USERUSED(buf
)) {
700 * We also always visit user/group accounting
701 * objects, and never skip them, even if we are
702 * pausing. This is necessary so that the space
703 * deltas from this txg get integrated.
705 dsl_scan_visitdnode(scn
, ds
, osp
->os_type
,
706 &osp
->os_groupused_dnode
,
707 DMU_GROUPUSED_OBJECT
, tx
);
708 dsl_scan_visitdnode(scn
, ds
, osp
->os_type
,
709 &osp
->os_userused_dnode
,
710 DMU_USERUSED_OBJECT
, tx
);
712 (void) arc_buf_remove_ref(buf
, &buf
);
719 dsl_scan_visitdnode(dsl_scan_t
*scn
, dsl_dataset_t
*ds
,
720 dmu_objset_type_t ostype
, dnode_phys_t
*dnp
,
721 uint64_t object
, dmu_tx_t
*tx
)
725 for (j
= 0; j
< dnp
->dn_nblkptr
; j
++) {
726 zbookmark_phys_t czb
;
728 SET_BOOKMARK(&czb
, ds
? ds
->ds_object
: 0, object
,
729 dnp
->dn_nlevels
- 1, j
);
730 dsl_scan_visitbp(&dnp
->dn_blkptr
[j
],
731 &czb
, dnp
, ds
, scn
, ostype
, tx
);
734 if (dnp
->dn_flags
& DNODE_FLAG_SPILL_BLKPTR
) {
735 zbookmark_phys_t czb
;
736 SET_BOOKMARK(&czb
, ds
? ds
->ds_object
: 0, object
,
738 dsl_scan_visitbp(&dnp
->dn_spill
,
739 &czb
, dnp
, ds
, scn
, ostype
, tx
);
744 * The arguments are in this order because mdb can only print the
745 * first 5; we want them to be useful.
748 dsl_scan_visitbp(blkptr_t
*bp
, const zbookmark_phys_t
*zb
,
749 dnode_phys_t
*dnp
, dsl_dataset_t
*ds
, dsl_scan_t
*scn
,
750 dmu_objset_type_t ostype
, dmu_tx_t
*tx
)
752 dsl_pool_t
*dp
= scn
->scn_dp
;
753 arc_buf_t
*buf
= NULL
;
754 blkptr_t bp_toread
= *bp
;
756 /* ASSERT(pbuf == NULL || arc_released(pbuf)); */
758 if (dsl_scan_check_pause(scn
, zb
))
761 if (dsl_scan_check_resume(scn
, dnp
, zb
))
767 scn
->scn_visited_this_txg
++;
770 "visiting ds=%p/%llu zb=%llx/%llx/%llx/%llx bp=%p",
771 ds
, ds
? ds
->ds_object
: 0,
772 zb
->zb_objset
, zb
->zb_object
, zb
->zb_level
, zb
->zb_blkid
,
775 if (bp
->blk_birth
<= scn
->scn_phys
.scn_cur_min_txg
)
778 if (dsl_scan_recurse(scn
, ds
, ostype
, dnp
, &bp_toread
, zb
, tx
) != 0)
782 * If dsl_scan_ddt() has aready visited this block, it will have
783 * already done any translations or scrubbing, so don't call the
786 if (ddt_class_contains(dp
->dp_spa
,
787 scn
->scn_phys
.scn_ddt_class_max
, bp
)) {
793 * If this block is from the future (after cur_max_txg), then we
794 * are doing this on behalf of a deleted snapshot, and we will
795 * revisit the future block on the next pass of this dataset.
796 * Don't scan it now unless we need to because something
797 * under it was modified.
799 if (BP_PHYSICAL_BIRTH(bp
) <= scn
->scn_phys
.scn_cur_max_txg
) {
800 scan_funcs
[scn
->scn_phys
.scn_func
](dp
, bp
, zb
);
805 dsl_scan_visit_rootbp(dsl_scan_t
*scn
, dsl_dataset_t
*ds
, blkptr_t
*bp
,
810 SET_BOOKMARK(&zb
, ds
? ds
->ds_object
: DMU_META_OBJSET
,
811 ZB_ROOT_OBJECT
, ZB_ROOT_LEVEL
, ZB_ROOT_BLKID
);
812 dsl_scan_visitbp(bp
, &zb
, NULL
,
813 ds
, scn
, DMU_OST_NONE
, tx
);
815 dprintf_ds(ds
, "finished scan%s", "");
819 dsl_scan_ds_destroyed(dsl_dataset_t
*ds
, dmu_tx_t
*tx
)
821 dsl_pool_t
*dp
= ds
->ds_dir
->dd_pool
;
822 dsl_scan_t
*scn
= dp
->dp_scan
;
825 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
828 if (scn
->scn_phys
.scn_bookmark
.zb_objset
== ds
->ds_object
) {
829 if (ds
->ds_is_snapshot
) {
832 * - scn_cur_{min,max}_txg stays the same.
833 * - Setting the flag is not really necessary if
834 * scn_cur_max_txg == scn_max_txg, because there
835 * is nothing after this snapshot that we care
836 * about. However, we set it anyway and then
837 * ignore it when we retraverse it in
838 * dsl_scan_visitds().
840 scn
->scn_phys
.scn_bookmark
.zb_objset
=
841 dsl_dataset_phys(ds
)->ds_next_snap_obj
;
842 zfs_dbgmsg("destroying ds %llu; currently traversing; "
843 "reset zb_objset to %llu",
844 (u_longlong_t
)ds
->ds_object
,
845 (u_longlong_t
)dsl_dataset_phys(ds
)->
847 scn
->scn_phys
.scn_flags
|= DSF_VISIT_DS_AGAIN
;
849 SET_BOOKMARK(&scn
->scn_phys
.scn_bookmark
,
850 ZB_DESTROYED_OBJSET
, 0, 0, 0);
851 zfs_dbgmsg("destroying ds %llu; currently traversing; "
852 "reset bookmark to -1,0,0,0",
853 (u_longlong_t
)ds
->ds_object
);
855 } else if (zap_lookup_int_key(dp
->dp_meta_objset
,
856 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
, &mintxg
) == 0) {
857 ASSERT3U(dsl_dataset_phys(ds
)->ds_num_children
, <=, 1);
858 VERIFY3U(0, ==, zap_remove_int(dp
->dp_meta_objset
,
859 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
, tx
));
860 if (ds
->ds_is_snapshot
) {
862 * We keep the same mintxg; it could be >
863 * ds_creation_txg if the previous snapshot was
866 VERIFY(zap_add_int_key(dp
->dp_meta_objset
,
867 scn
->scn_phys
.scn_queue_obj
,
868 dsl_dataset_phys(ds
)->ds_next_snap_obj
,
870 zfs_dbgmsg("destroying ds %llu; in queue; "
871 "replacing with %llu",
872 (u_longlong_t
)ds
->ds_object
,
873 (u_longlong_t
)dsl_dataset_phys(ds
)->
876 zfs_dbgmsg("destroying ds %llu; in queue; removing",
877 (u_longlong_t
)ds
->ds_object
);
882 * dsl_scan_sync() should be called after this, and should sync
883 * out our changed state, but just to be safe, do it here.
885 dsl_scan_sync_state(scn
, tx
);
889 dsl_scan_ds_snapshotted(dsl_dataset_t
*ds
, dmu_tx_t
*tx
)
891 dsl_pool_t
*dp
= ds
->ds_dir
->dd_pool
;
892 dsl_scan_t
*scn
= dp
->dp_scan
;
895 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
898 ASSERT(dsl_dataset_phys(ds
)->ds_prev_snap_obj
!= 0);
900 if (scn
->scn_phys
.scn_bookmark
.zb_objset
== ds
->ds_object
) {
901 scn
->scn_phys
.scn_bookmark
.zb_objset
=
902 dsl_dataset_phys(ds
)->ds_prev_snap_obj
;
903 zfs_dbgmsg("snapshotting ds %llu; currently traversing; "
904 "reset zb_objset to %llu",
905 (u_longlong_t
)ds
->ds_object
,
906 (u_longlong_t
)dsl_dataset_phys(ds
)->ds_prev_snap_obj
);
907 } else if (zap_lookup_int_key(dp
->dp_meta_objset
,
908 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
, &mintxg
) == 0) {
909 VERIFY3U(0, ==, zap_remove_int(dp
->dp_meta_objset
,
910 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
, tx
));
911 VERIFY(zap_add_int_key(dp
->dp_meta_objset
,
912 scn
->scn_phys
.scn_queue_obj
,
913 dsl_dataset_phys(ds
)->ds_prev_snap_obj
, mintxg
, tx
) == 0);
914 zfs_dbgmsg("snapshotting ds %llu; in queue; "
915 "replacing with %llu",
916 (u_longlong_t
)ds
->ds_object
,
917 (u_longlong_t
)dsl_dataset_phys(ds
)->ds_prev_snap_obj
);
919 dsl_scan_sync_state(scn
, tx
);
923 dsl_scan_ds_clone_swapped(dsl_dataset_t
*ds1
, dsl_dataset_t
*ds2
, dmu_tx_t
*tx
)
925 dsl_pool_t
*dp
= ds1
->ds_dir
->dd_pool
;
926 dsl_scan_t
*scn
= dp
->dp_scan
;
929 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
932 if (scn
->scn_phys
.scn_bookmark
.zb_objset
== ds1
->ds_object
) {
933 scn
->scn_phys
.scn_bookmark
.zb_objset
= ds2
->ds_object
;
934 zfs_dbgmsg("clone_swap ds %llu; currently traversing; "
935 "reset zb_objset to %llu",
936 (u_longlong_t
)ds1
->ds_object
,
937 (u_longlong_t
)ds2
->ds_object
);
938 } else if (scn
->scn_phys
.scn_bookmark
.zb_objset
== ds2
->ds_object
) {
939 scn
->scn_phys
.scn_bookmark
.zb_objset
= ds1
->ds_object
;
940 zfs_dbgmsg("clone_swap ds %llu; currently traversing; "
941 "reset zb_objset to %llu",
942 (u_longlong_t
)ds2
->ds_object
,
943 (u_longlong_t
)ds1
->ds_object
);
946 if (zap_lookup_int_key(dp
->dp_meta_objset
, scn
->scn_phys
.scn_queue_obj
,
947 ds1
->ds_object
, &mintxg
) == 0) {
950 ASSERT3U(mintxg
, ==, dsl_dataset_phys(ds1
)->ds_prev_snap_txg
);
951 ASSERT3U(mintxg
, ==, dsl_dataset_phys(ds2
)->ds_prev_snap_txg
);
952 VERIFY3U(0, ==, zap_remove_int(dp
->dp_meta_objset
,
953 scn
->scn_phys
.scn_queue_obj
, ds1
->ds_object
, tx
));
954 err
= zap_add_int_key(dp
->dp_meta_objset
,
955 scn
->scn_phys
.scn_queue_obj
, ds2
->ds_object
, mintxg
, tx
);
956 VERIFY(err
== 0 || err
== EEXIST
);
958 /* Both were there to begin with */
959 VERIFY(0 == zap_add_int_key(dp
->dp_meta_objset
,
960 scn
->scn_phys
.scn_queue_obj
,
961 ds1
->ds_object
, mintxg
, tx
));
963 zfs_dbgmsg("clone_swap ds %llu; in queue; "
964 "replacing with %llu",
965 (u_longlong_t
)ds1
->ds_object
,
966 (u_longlong_t
)ds2
->ds_object
);
967 } else if (zap_lookup_int_key(dp
->dp_meta_objset
,
968 scn
->scn_phys
.scn_queue_obj
, ds2
->ds_object
, &mintxg
) == 0) {
969 ASSERT3U(mintxg
, ==, dsl_dataset_phys(ds1
)->ds_prev_snap_txg
);
970 ASSERT3U(mintxg
, ==, dsl_dataset_phys(ds2
)->ds_prev_snap_txg
);
971 VERIFY3U(0, ==, zap_remove_int(dp
->dp_meta_objset
,
972 scn
->scn_phys
.scn_queue_obj
, ds2
->ds_object
, tx
));
973 VERIFY(0 == zap_add_int_key(dp
->dp_meta_objset
,
974 scn
->scn_phys
.scn_queue_obj
, ds1
->ds_object
, mintxg
, tx
));
975 zfs_dbgmsg("clone_swap ds %llu; in queue; "
976 "replacing with %llu",
977 (u_longlong_t
)ds2
->ds_object
,
978 (u_longlong_t
)ds1
->ds_object
);
981 dsl_scan_sync_state(scn
, tx
);
984 struct enqueue_clones_arg
{
991 enqueue_clones_cb(dsl_pool_t
*dp
, dsl_dataset_t
*hds
, void *arg
)
993 struct enqueue_clones_arg
*eca
= arg
;
996 dsl_scan_t
*scn
= dp
->dp_scan
;
998 if (dsl_dir_phys(hds
->ds_dir
)->dd_origin_obj
!= eca
->originobj
)
1001 err
= dsl_dataset_hold_obj(dp
, hds
->ds_object
, FTAG
, &ds
);
1005 while (dsl_dataset_phys(ds
)->ds_prev_snap_obj
!= eca
->originobj
) {
1006 dsl_dataset_t
*prev
;
1007 err
= dsl_dataset_hold_obj(dp
,
1008 dsl_dataset_phys(ds
)->ds_prev_snap_obj
, FTAG
, &prev
);
1010 dsl_dataset_rele(ds
, FTAG
);
1015 VERIFY(zap_add_int_key(dp
->dp_meta_objset
,
1016 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
,
1017 dsl_dataset_phys(ds
)->ds_prev_snap_txg
, eca
->tx
) == 0);
1018 dsl_dataset_rele(ds
, FTAG
);
1023 dsl_scan_visitds(dsl_scan_t
*scn
, uint64_t dsobj
, dmu_tx_t
*tx
)
1025 dsl_pool_t
*dp
= scn
->scn_dp
;
1029 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp
, dsobj
, FTAG
, &ds
));
1031 if (scn
->scn_phys
.scn_cur_min_txg
>=
1032 scn
->scn_phys
.scn_max_txg
) {
1034 * This can happen if this snapshot was created after the
1035 * scan started, and we already completed a previous snapshot
1036 * that was created after the scan started. This snapshot
1037 * only references blocks with:
1039 * birth < our ds_creation_txg
1040 * cur_min_txg is no less than ds_creation_txg.
1041 * We have already visited these blocks.
1043 * birth > scn_max_txg
1044 * The scan requested not to visit these blocks.
1046 * Subsequent snapshots (and clones) can reference our
1047 * blocks, or blocks with even higher birth times.
1048 * Therefore we do not need to visit them either,
1049 * so we do not add them to the work queue.
1051 * Note that checking for cur_min_txg >= cur_max_txg
1052 * is not sufficient, because in that case we may need to
1053 * visit subsequent snapshots. This happens when min_txg > 0,
1054 * which raises cur_min_txg. In this case we will visit
1055 * this dataset but skip all of its blocks, because the
1056 * rootbp's birth time is < cur_min_txg. Then we will
1057 * add the next snapshots/clones to the work queue.
1059 char *dsname
= kmem_alloc(MAXNAMELEN
, KM_SLEEP
);
1060 dsl_dataset_name(ds
, dsname
);
1061 zfs_dbgmsg("scanning dataset %llu (%s) is unnecessary because "
1062 "cur_min_txg (%llu) >= max_txg (%llu)",
1064 scn
->scn_phys
.scn_cur_min_txg
,
1065 scn
->scn_phys
.scn_max_txg
);
1066 kmem_free(dsname
, MAXNAMELEN
);
1071 if (dmu_objset_from_ds(ds
, &os
))
1075 * Only the ZIL in the head (non-snapshot) is valid. Even though
1076 * snapshots can have ZIL block pointers (which may be the same
1077 * BP as in the head), they must be ignored. So we traverse the
1078 * ZIL here, rather than in scan_recurse(), because the regular
1079 * snapshot block-sharing rules don't apply to it.
1081 if (DSL_SCAN_IS_SCRUB_RESILVER(scn
) && !ds
->ds_is_snapshot
)
1082 dsl_scan_zil(dp
, &os
->os_zil_header
);
1085 * Iterate over the bps in this ds.
1087 dmu_buf_will_dirty(ds
->ds_dbuf
, tx
);
1088 dsl_scan_visit_rootbp(scn
, ds
, &dsl_dataset_phys(ds
)->ds_bp
, tx
);
1090 char *dsname
= kmem_alloc(ZFS_MAXNAMELEN
, KM_SLEEP
);
1091 dsl_dataset_name(ds
, dsname
);
1092 zfs_dbgmsg("scanned dataset %llu (%s) with min=%llu max=%llu; "
1094 (longlong_t
)dsobj
, dsname
,
1095 (longlong_t
)scn
->scn_phys
.scn_cur_min_txg
,
1096 (longlong_t
)scn
->scn_phys
.scn_cur_max_txg
,
1097 (int)scn
->scn_pausing
);
1098 kmem_free(dsname
, ZFS_MAXNAMELEN
);
1100 if (scn
->scn_pausing
)
1104 * We've finished this pass over this dataset.
1108 * If we did not completely visit this dataset, do another pass.
1110 if (scn
->scn_phys
.scn_flags
& DSF_VISIT_DS_AGAIN
) {
1111 zfs_dbgmsg("incomplete pass; visiting again");
1112 scn
->scn_phys
.scn_flags
&= ~DSF_VISIT_DS_AGAIN
;
1113 VERIFY(zap_add_int_key(dp
->dp_meta_objset
,
1114 scn
->scn_phys
.scn_queue_obj
, ds
->ds_object
,
1115 scn
->scn_phys
.scn_cur_max_txg
, tx
) == 0);
1120 * Add descendent datasets to work queue.
1122 if (dsl_dataset_phys(ds
)->ds_next_snap_obj
!= 0) {
1123 VERIFY(zap_add_int_key(dp
->dp_meta_objset
,
1124 scn
->scn_phys
.scn_queue_obj
,
1125 dsl_dataset_phys(ds
)->ds_next_snap_obj
,
1126 dsl_dataset_phys(ds
)->ds_creation_txg
, tx
) == 0);
1128 if (dsl_dataset_phys(ds
)->ds_num_children
> 1) {
1129 boolean_t usenext
= B_FALSE
;
1130 if (dsl_dataset_phys(ds
)->ds_next_clones_obj
!= 0) {
1133 * A bug in a previous version of the code could
1134 * cause upgrade_clones_cb() to not set
1135 * ds_next_snap_obj when it should, leading to a
1136 * missing entry. Therefore we can only use the
1137 * next_clones_obj when its count is correct.
1139 int err
= zap_count(dp
->dp_meta_objset
,
1140 dsl_dataset_phys(ds
)->ds_next_clones_obj
, &count
);
1142 count
== dsl_dataset_phys(ds
)->ds_num_children
- 1)
1147 VERIFY0(zap_join_key(dp
->dp_meta_objset
,
1148 dsl_dataset_phys(ds
)->ds_next_clones_obj
,
1149 scn
->scn_phys
.scn_queue_obj
,
1150 dsl_dataset_phys(ds
)->ds_creation_txg
, tx
));
1152 struct enqueue_clones_arg eca
;
1154 eca
.originobj
= ds
->ds_object
;
1156 VERIFY0(dmu_objset_find_dp(dp
, dp
->dp_root_dir_obj
,
1157 enqueue_clones_cb
, &eca
, DS_FIND_CHILDREN
));
1162 dsl_dataset_rele(ds
, FTAG
);
1167 enqueue_cb(dsl_pool_t
*dp
, dsl_dataset_t
*hds
, void *arg
)
1172 dsl_scan_t
*scn
= dp
->dp_scan
;
1174 err
= dsl_dataset_hold_obj(dp
, hds
->ds_object
, FTAG
, &ds
);
1178 while (dsl_dataset_phys(ds
)->ds_prev_snap_obj
!= 0) {
1179 dsl_dataset_t
*prev
;
1180 err
= dsl_dataset_hold_obj(dp
,
1181 dsl_dataset_phys(ds
)->ds_prev_snap_obj
, FTAG
, &prev
);
1183 dsl_dataset_rele(ds
, FTAG
);
1188 * If this is a clone, we don't need to worry about it for now.
1190 if (dsl_dataset_phys(prev
)->ds_next_snap_obj
!= ds
->ds_object
) {
1191 dsl_dataset_rele(ds
, FTAG
);
1192 dsl_dataset_rele(prev
, FTAG
);
1195 dsl_dataset_rele(ds
, FTAG
);
1199 VERIFY(zap_add_int_key(dp
->dp_meta_objset
, scn
->scn_phys
.scn_queue_obj
,
1200 ds
->ds_object
, dsl_dataset_phys(ds
)->ds_prev_snap_txg
, tx
) == 0);
1201 dsl_dataset_rele(ds
, FTAG
);
1206 * Scrub/dedup interaction.
1208 * If there are N references to a deduped block, we don't want to scrub it
1209 * N times -- ideally, we should scrub it exactly once.
1211 * We leverage the fact that the dde's replication class (enum ddt_class)
1212 * is ordered from highest replication class (DDT_CLASS_DITTO) to lowest
1213 * (DDT_CLASS_UNIQUE) so that we may walk the DDT in that order.
1215 * To prevent excess scrubbing, the scrub begins by walking the DDT
1216 * to find all blocks with refcnt > 1, and scrubs each of these once.
1217 * Since there are two replication classes which contain blocks with
1218 * refcnt > 1, we scrub the highest replication class (DDT_CLASS_DITTO) first.
1219 * Finally the top-down scrub begins, only visiting blocks with refcnt == 1.
1221 * There would be nothing more to say if a block's refcnt couldn't change
1222 * during a scrub, but of course it can so we must account for changes
1223 * in a block's replication class.
1225 * Here's an example of what can occur:
1227 * If a block has refcnt > 1 during the DDT scrub phase, but has refcnt == 1
1228 * when visited during the top-down scrub phase, it will be scrubbed twice.
1229 * This negates our scrub optimization, but is otherwise harmless.
1231 * If a block has refcnt == 1 during the DDT scrub phase, but has refcnt > 1
1232 * on each visit during the top-down scrub phase, it will never be scrubbed.
1233 * To catch this, ddt_sync_entry() notifies the scrub code whenever a block's
1234 * reference class transitions to a higher level (i.e DDT_CLASS_UNIQUE to
1235 * DDT_CLASS_DUPLICATE); if it transitions from refcnt == 1 to refcnt > 1
1236 * while a scrub is in progress, it scrubs the block right then.
1239 dsl_scan_ddt(dsl_scan_t
*scn
, dmu_tx_t
*tx
)
1241 ddt_bookmark_t
*ddb
= &scn
->scn_phys
.scn_ddt_bookmark
;
1242 ddt_entry_t dde
= { 0 };
1246 while ((error
= ddt_walk(scn
->scn_dp
->dp_spa
, ddb
, &dde
)) == 0) {
1249 if (ddb
->ddb_class
> scn
->scn_phys
.scn_ddt_class_max
)
1251 dprintf("visiting ddb=%llu/%llu/%llu/%llx\n",
1252 (longlong_t
)ddb
->ddb_class
,
1253 (longlong_t
)ddb
->ddb_type
,
1254 (longlong_t
)ddb
->ddb_checksum
,
1255 (longlong_t
)ddb
->ddb_cursor
);
1257 /* There should be no pending changes to the dedup table */
1258 ddt
= scn
->scn_dp
->dp_spa
->spa_ddt
[ddb
->ddb_checksum
];
1259 ASSERT(avl_first(&ddt
->ddt_tree
) == NULL
);
1261 dsl_scan_ddt_entry(scn
, ddb
->ddb_checksum
, &dde
, tx
);
1264 if (dsl_scan_check_pause(scn
, NULL
))
1268 zfs_dbgmsg("scanned %llu ddt entries with class_max = %u; pausing=%u",
1269 (longlong_t
)n
, (int)scn
->scn_phys
.scn_ddt_class_max
,
1270 (int)scn
->scn_pausing
);
1272 ASSERT(error
== 0 || error
== ENOENT
);
1273 ASSERT(error
!= ENOENT
||
1274 ddb
->ddb_class
> scn
->scn_phys
.scn_ddt_class_max
);
1279 dsl_scan_ddt_entry(dsl_scan_t
*scn
, enum zio_checksum checksum
,
1280 ddt_entry_t
*dde
, dmu_tx_t
*tx
)
1282 const ddt_key_t
*ddk
= &dde
->dde_key
;
1283 ddt_phys_t
*ddp
= dde
->dde_phys
;
1285 zbookmark_phys_t zb
= { 0 };
1287 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
1290 for (int p
= 0; p
< DDT_PHYS_TYPES
; p
++, ddp
++) {
1291 if (ddp
->ddp_phys_birth
== 0 ||
1292 ddp
->ddp_phys_birth
> scn
->scn_phys
.scn_max_txg
)
1294 ddt_bp_create(checksum
, ddk
, ddp
, &bp
);
1296 scn
->scn_visited_this_txg
++;
1297 scan_funcs
[scn
->scn_phys
.scn_func
](scn
->scn_dp
, &bp
, &zb
);
1302 dsl_scan_visit(dsl_scan_t
*scn
, dmu_tx_t
*tx
)
1304 dsl_pool_t
*dp
= scn
->scn_dp
;
1308 if (scn
->scn_phys
.scn_ddt_bookmark
.ddb_class
<=
1309 scn
->scn_phys
.scn_ddt_class_max
) {
1310 scn
->scn_phys
.scn_cur_min_txg
= scn
->scn_phys
.scn_min_txg
;
1311 scn
->scn_phys
.scn_cur_max_txg
= scn
->scn_phys
.scn_max_txg
;
1312 dsl_scan_ddt(scn
, tx
);
1313 if (scn
->scn_pausing
)
1317 if (scn
->scn_phys
.scn_bookmark
.zb_objset
== DMU_META_OBJSET
) {
1318 /* First do the MOS & ORIGIN */
1320 scn
->scn_phys
.scn_cur_min_txg
= scn
->scn_phys
.scn_min_txg
;
1321 scn
->scn_phys
.scn_cur_max_txg
= scn
->scn_phys
.scn_max_txg
;
1322 dsl_scan_visit_rootbp(scn
, NULL
,
1323 &dp
->dp_meta_rootbp
, tx
);
1324 spa_set_rootblkptr(dp
->dp_spa
, &dp
->dp_meta_rootbp
);
1325 if (scn
->scn_pausing
)
1328 if (spa_version(dp
->dp_spa
) < SPA_VERSION_DSL_SCRUB
) {
1329 VERIFY0(dmu_objset_find_dp(dp
, dp
->dp_root_dir_obj
,
1330 enqueue_cb
, tx
, DS_FIND_CHILDREN
));
1332 dsl_scan_visitds(scn
,
1333 dp
->dp_origin_snap
->ds_object
, tx
);
1335 ASSERT(!scn
->scn_pausing
);
1336 } else if (scn
->scn_phys
.scn_bookmark
.zb_objset
!=
1337 ZB_DESTROYED_OBJSET
) {
1339 * If we were paused, continue from here. Note if the
1340 * ds we were paused on was deleted, the zb_objset may
1341 * be -1, so we will skip this and find a new objset
1344 dsl_scan_visitds(scn
, scn
->scn_phys
.scn_bookmark
.zb_objset
, tx
);
1345 if (scn
->scn_pausing
)
1350 * In case we were paused right at the end of the ds, zero the
1351 * bookmark so we don't think that we're still trying to resume.
1353 bzero(&scn
->scn_phys
.scn_bookmark
, sizeof (zbookmark_phys_t
));
1355 /* keep pulling things out of the zap-object-as-queue */
1356 while (zap_cursor_init(&zc
, dp
->dp_meta_objset
,
1357 scn
->scn_phys
.scn_queue_obj
),
1358 zap_cursor_retrieve(&zc
, &za
) == 0) {
1362 dsobj
= strtonum(za
.za_name
, NULL
);
1363 VERIFY3U(0, ==, zap_remove_int(dp
->dp_meta_objset
,
1364 scn
->scn_phys
.scn_queue_obj
, dsobj
, tx
));
1366 /* Set up min/max txg */
1367 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp
, dsobj
, FTAG
, &ds
));
1368 if (za
.za_first_integer
!= 0) {
1369 scn
->scn_phys
.scn_cur_min_txg
=
1370 MAX(scn
->scn_phys
.scn_min_txg
,
1371 za
.za_first_integer
);
1373 scn
->scn_phys
.scn_cur_min_txg
=
1374 MAX(scn
->scn_phys
.scn_min_txg
,
1375 dsl_dataset_phys(ds
)->ds_prev_snap_txg
);
1377 scn
->scn_phys
.scn_cur_max_txg
= dsl_scan_ds_maxtxg(ds
);
1378 dsl_dataset_rele(ds
, FTAG
);
1380 dsl_scan_visitds(scn
, dsobj
, tx
);
1381 zap_cursor_fini(&zc
);
1382 if (scn
->scn_pausing
)
1385 zap_cursor_fini(&zc
);
1389 dsl_scan_free_should_pause(dsl_scan_t
*scn
)
1391 uint64_t elapsed_nanosecs
;
1396 if (scn
->scn_visited_this_txg
>= zfs_free_max_blocks
)
1399 elapsed_nanosecs
= gethrtime() - scn
->scn_sync_start_time
;
1400 return (elapsed_nanosecs
/ NANOSEC
> zfs_txg_timeout
||
1401 (NSEC2MSEC(elapsed_nanosecs
) > zfs_free_min_time_ms
&&
1402 txg_sync_waiting(scn
->scn_dp
)) ||
1403 spa_shutting_down(scn
->scn_dp
->dp_spa
));
1407 dsl_scan_free_block_cb(void *arg
, const blkptr_t
*bp
, dmu_tx_t
*tx
)
1409 dsl_scan_t
*scn
= arg
;
1411 if (!scn
->scn_is_bptree
||
1412 (BP_GET_LEVEL(bp
) == 0 && BP_GET_TYPE(bp
) != DMU_OT_OBJSET
)) {
1413 if (dsl_scan_free_should_pause(scn
))
1414 return (SET_ERROR(ERESTART
));
1417 zio_nowait(zio_free_sync(scn
->scn_zio_root
, scn
->scn_dp
->dp_spa
,
1418 dmu_tx_get_txg(tx
), bp
, 0));
1419 dsl_dir_diduse_space(tx
->tx_pool
->dp_free_dir
, DD_USED_HEAD
,
1420 -bp_get_dsize_sync(scn
->scn_dp
->dp_spa
, bp
),
1421 -BP_GET_PSIZE(bp
), -BP_GET_UCSIZE(bp
), tx
);
1422 scn
->scn_visited_this_txg
++;
1427 dsl_scan_active(dsl_scan_t
*scn
)
1429 spa_t
*spa
= scn
->scn_dp
->dp_spa
;
1430 uint64_t used
= 0, comp
, uncomp
;
1432 if (spa
->spa_load_state
!= SPA_LOAD_NONE
)
1434 if (spa_shutting_down(spa
))
1436 if (scn
->scn_phys
.scn_state
== DSS_SCANNING
||
1437 (scn
->scn_async_destroying
&& !scn
->scn_async_stalled
))
1440 if (spa_version(scn
->scn_dp
->dp_spa
) >= SPA_VERSION_DEADLISTS
) {
1441 (void) bpobj_space(&scn
->scn_dp
->dp_free_bpobj
,
1442 &used
, &comp
, &uncomp
);
1448 dsl_scan_sync(dsl_pool_t
*dp
, dmu_tx_t
*tx
)
1450 dsl_scan_t
*scn
= dp
->dp_scan
;
1451 spa_t
*spa
= dp
->dp_spa
;
1455 * Check for scn_restart_txg before checking spa_load_state, so
1456 * that we can restart an old-style scan while the pool is being
1457 * imported (see dsl_scan_init).
1459 if (dsl_scan_restarting(scn
, tx
)) {
1460 pool_scan_func_t func
= POOL_SCAN_SCRUB
;
1461 dsl_scan_done(scn
, B_FALSE
, tx
);
1462 if (vdev_resilver_needed(spa
->spa_root_vdev
, NULL
, NULL
))
1463 func
= POOL_SCAN_RESILVER
;
1464 zfs_dbgmsg("restarting scan func=%u txg=%llu",
1466 dsl_scan_setup_sync(&func
, tx
);
1470 * Only process scans in sync pass 1.
1472 if (spa_sync_pass(dp
->dp_spa
) > 1)
1476 * If the spa is shutting down, then stop scanning. This will
1477 * ensure that the scan does not dirty any new data during the
1480 if (spa_shutting_down(spa
))
1484 * If the scan is inactive due to a stalled async destroy, try again.
1486 if (!scn
->scn_async_stalled
&& !dsl_scan_active(scn
))
1489 scn
->scn_visited_this_txg
= 0;
1490 scn
->scn_pausing
= B_FALSE
;
1491 scn
->scn_sync_start_time
= gethrtime();
1492 spa
->spa_scrub_active
= B_TRUE
;
1495 * First process the async destroys. If we pause, don't do
1496 * any scrubbing or resilvering. This ensures that there are no
1497 * async destroys while we are scanning, so the scan code doesn't
1498 * have to worry about traversing it. It is also faster to free the
1499 * blocks than to scrub them.
1501 if (zfs_free_bpobj_enabled
&&
1502 spa_version(dp
->dp_spa
) >= SPA_VERSION_DEADLISTS
) {
1503 scn
->scn_is_bptree
= B_FALSE
;
1504 scn
->scn_zio_root
= zio_root(dp
->dp_spa
, NULL
,
1505 NULL
, ZIO_FLAG_MUSTSUCCEED
);
1506 err
= bpobj_iterate(&dp
->dp_free_bpobj
,
1507 dsl_scan_free_block_cb
, scn
, tx
);
1508 VERIFY3U(0, ==, zio_wait(scn
->scn_zio_root
));
1510 if (err
!= 0 && err
!= ERESTART
)
1511 zfs_panic_recover("error %u from bpobj_iterate()", err
);
1514 if (err
== 0 && spa_feature_is_active(spa
, SPA_FEATURE_ASYNC_DESTROY
)) {
1515 ASSERT(scn
->scn_async_destroying
);
1516 scn
->scn_is_bptree
= B_TRUE
;
1517 scn
->scn_zio_root
= zio_root(dp
->dp_spa
, NULL
,
1518 NULL
, ZIO_FLAG_MUSTSUCCEED
);
1519 err
= bptree_iterate(dp
->dp_meta_objset
,
1520 dp
->dp_bptree_obj
, B_TRUE
, dsl_scan_free_block_cb
, scn
, tx
);
1521 VERIFY0(zio_wait(scn
->scn_zio_root
));
1523 if (err
== EIO
|| err
== ECKSUM
) {
1525 } else if (err
!= 0 && err
!= ERESTART
) {
1526 zfs_panic_recover("error %u from "
1527 "traverse_dataset_destroyed()", err
);
1530 if (bptree_is_empty(dp
->dp_meta_objset
, dp
->dp_bptree_obj
)) {
1531 /* finished; deactivate async destroy feature */
1532 spa_feature_decr(spa
, SPA_FEATURE_ASYNC_DESTROY
, tx
);
1533 ASSERT(!spa_feature_is_active(spa
,
1534 SPA_FEATURE_ASYNC_DESTROY
));
1535 VERIFY0(zap_remove(dp
->dp_meta_objset
,
1536 DMU_POOL_DIRECTORY_OBJECT
,
1537 DMU_POOL_BPTREE_OBJ
, tx
));
1538 VERIFY0(bptree_free(dp
->dp_meta_objset
,
1539 dp
->dp_bptree_obj
, tx
));
1540 dp
->dp_bptree_obj
= 0;
1541 scn
->scn_async_destroying
= B_FALSE
;
1542 scn
->scn_async_stalled
= B_FALSE
;
1545 * If we didn't make progress, mark the async
1546 * destroy as stalled, so that we will not initiate
1547 * a spa_sync() on its behalf. Note that we only
1548 * check this if we are not finished, because if the
1549 * bptree had no blocks for us to visit, we can
1550 * finish without "making progress".
1552 scn
->scn_async_stalled
=
1553 (scn
->scn_visited_this_txg
== 0);
1556 if (scn
->scn_visited_this_txg
) {
1557 zfs_dbgmsg("freed %llu blocks in %llums from "
1558 "free_bpobj/bptree txg %llu; err=%u",
1559 (longlong_t
)scn
->scn_visited_this_txg
,
1561 NSEC2MSEC(gethrtime() - scn
->scn_sync_start_time
),
1562 (longlong_t
)tx
->tx_txg
, err
);
1563 scn
->scn_visited_this_txg
= 0;
1566 * Write out changes to the DDT that may be required as a
1567 * result of the blocks freed. This ensures that the DDT
1568 * is clean when a scrub/resilver runs.
1570 ddt_sync(spa
, tx
->tx_txg
);
1574 if (dp
->dp_free_dir
!= NULL
&& !scn
->scn_async_destroying
&&
1575 zfs_free_leak_on_eio
&&
1576 (dsl_dir_phys(dp
->dp_free_dir
)->dd_used_bytes
!= 0 ||
1577 dsl_dir_phys(dp
->dp_free_dir
)->dd_compressed_bytes
!= 0 ||
1578 dsl_dir_phys(dp
->dp_free_dir
)->dd_uncompressed_bytes
!= 0)) {
1580 * We have finished background destroying, but there is still
1581 * some space left in the dp_free_dir. Transfer this leaked
1582 * space to the dp_leak_dir.
1584 if (dp
->dp_leak_dir
== NULL
) {
1585 rrw_enter(&dp
->dp_config_rwlock
, RW_WRITER
, FTAG
);
1586 (void) dsl_dir_create_sync(dp
, dp
->dp_root_dir
,
1588 VERIFY0(dsl_pool_open_special_dir(dp
,
1589 LEAK_DIR_NAME
, &dp
->dp_leak_dir
));
1590 rrw_exit(&dp
->dp_config_rwlock
, FTAG
);
1592 dsl_dir_diduse_space(dp
->dp_leak_dir
, DD_USED_HEAD
,
1593 dsl_dir_phys(dp
->dp_free_dir
)->dd_used_bytes
,
1594 dsl_dir_phys(dp
->dp_free_dir
)->dd_compressed_bytes
,
1595 dsl_dir_phys(dp
->dp_free_dir
)->dd_uncompressed_bytes
, tx
);
1596 dsl_dir_diduse_space(dp
->dp_free_dir
, DD_USED_HEAD
,
1597 -dsl_dir_phys(dp
->dp_free_dir
)->dd_used_bytes
,
1598 -dsl_dir_phys(dp
->dp_free_dir
)->dd_compressed_bytes
,
1599 -dsl_dir_phys(dp
->dp_free_dir
)->dd_uncompressed_bytes
, tx
);
1601 if (dp
->dp_free_dir
!= NULL
&& !scn
->scn_async_destroying
) {
1602 /* finished; verify that space accounting went to zero */
1603 ASSERT0(dsl_dir_phys(dp
->dp_free_dir
)->dd_used_bytes
);
1604 ASSERT0(dsl_dir_phys(dp
->dp_free_dir
)->dd_compressed_bytes
);
1605 ASSERT0(dsl_dir_phys(dp
->dp_free_dir
)->dd_uncompressed_bytes
);
1608 if (scn
->scn_phys
.scn_state
!= DSS_SCANNING
)
1611 if (scn
->scn_done_txg
== tx
->tx_txg
) {
1612 ASSERT(!scn
->scn_pausing
);
1613 /* finished with scan. */
1614 zfs_dbgmsg("txg %llu scan complete", tx
->tx_txg
);
1615 dsl_scan_done(scn
, B_TRUE
, tx
);
1616 ASSERT3U(spa
->spa_scrub_inflight
, ==, 0);
1617 dsl_scan_sync_state(scn
, tx
);
1621 if (scn
->scn_phys
.scn_ddt_bookmark
.ddb_class
<=
1622 scn
->scn_phys
.scn_ddt_class_max
) {
1623 zfs_dbgmsg("doing scan sync txg %llu; "
1624 "ddt bm=%llu/%llu/%llu/%llx",
1625 (longlong_t
)tx
->tx_txg
,
1626 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_class
,
1627 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_type
,
1628 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_checksum
,
1629 (longlong_t
)scn
->scn_phys
.scn_ddt_bookmark
.ddb_cursor
);
1630 ASSERT(scn
->scn_phys
.scn_bookmark
.zb_objset
== 0);
1631 ASSERT(scn
->scn_phys
.scn_bookmark
.zb_object
== 0);
1632 ASSERT(scn
->scn_phys
.scn_bookmark
.zb_level
== 0);
1633 ASSERT(scn
->scn_phys
.scn_bookmark
.zb_blkid
== 0);
1635 zfs_dbgmsg("doing scan sync txg %llu; bm=%llu/%llu/%llu/%llu",
1636 (longlong_t
)tx
->tx_txg
,
1637 (longlong_t
)scn
->scn_phys
.scn_bookmark
.zb_objset
,
1638 (longlong_t
)scn
->scn_phys
.scn_bookmark
.zb_object
,
1639 (longlong_t
)scn
->scn_phys
.scn_bookmark
.zb_level
,
1640 (longlong_t
)scn
->scn_phys
.scn_bookmark
.zb_blkid
);
1643 scn
->scn_zio_root
= zio_root(dp
->dp_spa
, NULL
,
1644 NULL
, ZIO_FLAG_CANFAIL
);
1645 dsl_pool_config_enter(dp
, FTAG
);
1646 dsl_scan_visit(scn
, tx
);
1647 dsl_pool_config_exit(dp
, FTAG
);
1648 (void) zio_wait(scn
->scn_zio_root
);
1649 scn
->scn_zio_root
= NULL
;
1651 zfs_dbgmsg("visited %llu blocks in %llums",
1652 (longlong_t
)scn
->scn_visited_this_txg
,
1653 (longlong_t
)NSEC2MSEC(gethrtime() - scn
->scn_sync_start_time
));
1655 if (!scn
->scn_pausing
) {
1656 scn
->scn_done_txg
= tx
->tx_txg
+ 1;
1657 zfs_dbgmsg("txg %llu traversal complete, waiting till txg %llu",
1658 tx
->tx_txg
, scn
->scn_done_txg
);
1661 if (DSL_SCAN_IS_SCRUB_RESILVER(scn
)) {
1662 mutex_enter(&spa
->spa_scrub_lock
);
1663 while (spa
->spa_scrub_inflight
> 0) {
1664 cv_wait(&spa
->spa_scrub_io_cv
,
1665 &spa
->spa_scrub_lock
);
1667 mutex_exit(&spa
->spa_scrub_lock
);
1670 dsl_scan_sync_state(scn
, tx
);
1674 * This will start a new scan, or restart an existing one.
1677 dsl_resilver_restart(dsl_pool_t
*dp
, uint64_t txg
)
1681 tx
= dmu_tx_create_dd(dp
->dp_mos_dir
);
1682 VERIFY(0 == dmu_tx_assign(tx
, TXG_WAIT
));
1684 txg
= dmu_tx_get_txg(tx
);
1685 dp
->dp_scan
->scn_restart_txg
= txg
;
1688 dp
->dp_scan
->scn_restart_txg
= txg
;
1690 zfs_dbgmsg("restarting resilver txg=%llu", txg
);
1694 dsl_scan_resilvering(dsl_pool_t
*dp
)
1696 return (dp
->dp_scan
->scn_phys
.scn_state
== DSS_SCANNING
&&
1697 dp
->dp_scan
->scn_phys
.scn_func
== POOL_SCAN_RESILVER
);
1705 count_block(zfs_all_blkstats_t
*zab
, const blkptr_t
*bp
)
1710 * If we resume after a reboot, zab will be NULL; don't record
1711 * incomplete stats in that case.
1716 for (i
= 0; i
< 4; i
++) {
1717 int l
= (i
< 2) ? BP_GET_LEVEL(bp
) : DN_MAX_LEVELS
;
1718 int t
= (i
& 1) ? BP_GET_TYPE(bp
) : DMU_OT_TOTAL
;
1719 if (t
& DMU_OT_NEWTYPE
)
1721 zfs_blkstat_t
*zb
= &zab
->zab_type
[l
][t
];
1725 zb
->zb_asize
+= BP_GET_ASIZE(bp
);
1726 zb
->zb_lsize
+= BP_GET_LSIZE(bp
);
1727 zb
->zb_psize
+= BP_GET_PSIZE(bp
);
1728 zb
->zb_gangs
+= BP_COUNT_GANG(bp
);
1730 switch (BP_GET_NDVAS(bp
)) {
1732 if (DVA_GET_VDEV(&bp
->blk_dva
[0]) ==
1733 DVA_GET_VDEV(&bp
->blk_dva
[1]))
1734 zb
->zb_ditto_2_of_2_samevdev
++;
1737 equal
= (DVA_GET_VDEV(&bp
->blk_dva
[0]) ==
1738 DVA_GET_VDEV(&bp
->blk_dva
[1])) +
1739 (DVA_GET_VDEV(&bp
->blk_dva
[0]) ==
1740 DVA_GET_VDEV(&bp
->blk_dva
[2])) +
1741 (DVA_GET_VDEV(&bp
->blk_dva
[1]) ==
1742 DVA_GET_VDEV(&bp
->blk_dva
[2]));
1744 zb
->zb_ditto_2_of_3_samevdev
++;
1745 else if (equal
== 3)
1746 zb
->zb_ditto_3_of_3_samevdev
++;
1753 dsl_scan_scrub_done(zio_t
*zio
)
1755 spa_t
*spa
= zio
->io_spa
;
1757 zio_data_buf_free(zio
->io_data
, zio
->io_size
);
1759 mutex_enter(&spa
->spa_scrub_lock
);
1760 spa
->spa_scrub_inflight
--;
1761 cv_broadcast(&spa
->spa_scrub_io_cv
);
1763 if (zio
->io_error
&& (zio
->io_error
!= ECKSUM
||
1764 !(zio
->io_flags
& ZIO_FLAG_SPECULATIVE
))) {
1765 spa
->spa_dsl_pool
->dp_scan
->scn_phys
.scn_errors
++;
1767 mutex_exit(&spa
->spa_scrub_lock
);
1771 dsl_scan_scrub_cb(dsl_pool_t
*dp
,
1772 const blkptr_t
*bp
, const zbookmark_phys_t
*zb
)
1774 dsl_scan_t
*scn
= dp
->dp_scan
;
1775 size_t size
= BP_GET_PSIZE(bp
);
1776 spa_t
*spa
= dp
->dp_spa
;
1777 uint64_t phys_birth
= BP_PHYSICAL_BIRTH(bp
);
1779 int zio_flags
= ZIO_FLAG_SCAN_THREAD
| ZIO_FLAG_RAW
| ZIO_FLAG_CANFAIL
;
1782 if (phys_birth
<= scn
->scn_phys
.scn_min_txg
||
1783 phys_birth
>= scn
->scn_phys
.scn_max_txg
)
1786 count_block(dp
->dp_blkstats
, bp
);
1788 if (BP_IS_EMBEDDED(bp
))
1791 ASSERT(DSL_SCAN_IS_SCRUB_RESILVER(scn
));
1792 if (scn
->scn_phys
.scn_func
== POOL_SCAN_SCRUB
) {
1793 zio_flags
|= ZIO_FLAG_SCRUB
;
1795 scan_delay
= zfs_scrub_delay
;
1797 ASSERT3U(scn
->scn_phys
.scn_func
, ==, POOL_SCAN_RESILVER
);
1798 zio_flags
|= ZIO_FLAG_RESILVER
;
1800 scan_delay
= zfs_resilver_delay
;
1803 /* If it's an intent log block, failure is expected. */
1804 if (zb
->zb_level
== ZB_ZIL_LEVEL
)
1805 zio_flags
|= ZIO_FLAG_SPECULATIVE
;
1807 for (int d
= 0; d
< BP_GET_NDVAS(bp
); d
++) {
1808 vdev_t
*vd
= vdev_lookup_top(spa
,
1809 DVA_GET_VDEV(&bp
->blk_dva
[d
]));
1812 * Keep track of how much data we've examined so that
1813 * zpool(1M) status can make useful progress reports.
1815 scn
->scn_phys
.scn_examined
+= DVA_GET_ASIZE(&bp
->blk_dva
[d
]);
1816 spa
->spa_scan_pass_exam
+= DVA_GET_ASIZE(&bp
->blk_dva
[d
]);
1818 /* if it's a resilver, this may not be in the target range */
1820 if (DVA_GET_GANG(&bp
->blk_dva
[d
])) {
1822 * Gang members may be spread across multiple
1823 * vdevs, so the best estimate we have is the
1824 * scrub range, which has already been checked.
1825 * XXX -- it would be better to change our
1826 * allocation policy to ensure that all
1827 * gang members reside on the same vdev.
1831 needs_io
= vdev_dtl_contains(vd
, DTL_PARTIAL
,
1837 if (needs_io
&& !zfs_no_scrub_io
) {
1838 vdev_t
*rvd
= spa
->spa_root_vdev
;
1839 uint64_t maxinflight
= rvd
->vdev_children
* zfs_top_maxinflight
;
1840 void *data
= zio_data_buf_alloc(size
);
1842 mutex_enter(&spa
->spa_scrub_lock
);
1843 while (spa
->spa_scrub_inflight
>= maxinflight
)
1844 cv_wait(&spa
->spa_scrub_io_cv
, &spa
->spa_scrub_lock
);
1845 spa
->spa_scrub_inflight
++;
1846 mutex_exit(&spa
->spa_scrub_lock
);
1849 * If we're seeing recent (zfs_scan_idle) "important" I/Os
1850 * then throttle our workload to limit the impact of a scan.
1852 if (ddi_get_lbolt64() - spa
->spa_last_io
<= zfs_scan_idle
)
1855 zio_nowait(zio_read(NULL
, spa
, bp
, data
, size
,
1856 dsl_scan_scrub_done
, NULL
, ZIO_PRIORITY_SCRUB
,
1860 /* do not relocate this block */
1865 dsl_scan(dsl_pool_t
*dp
, pool_scan_func_t func
)
1867 spa_t
*spa
= dp
->dp_spa
;
1870 * Purge all vdev caches and probe all devices. We do this here
1871 * rather than in sync context because this requires a writer lock
1872 * on the spa_config lock, which we can't do from sync context. The
1873 * spa_scrub_reopen flag indicates that vdev_open() should not
1874 * attempt to start another scrub.
1876 spa_vdev_state_enter(spa
, SCL_NONE
);
1877 spa
->spa_scrub_reopen
= B_TRUE
;
1878 vdev_reopen(spa
->spa_root_vdev
);
1879 spa
->spa_scrub_reopen
= B_FALSE
;
1880 (void) spa_vdev_state_exit(spa
, NULL
, 0);
1882 return (dsl_sync_task(spa_name(spa
), dsl_scan_setup_check
,
1883 dsl_scan_setup_sync
, &func
, 0, ZFS_SPACE_CHECK_NONE
));
1887 dsl_scan_restarting(dsl_scan_t
*scn
, dmu_tx_t
*tx
)
1889 return (scn
->scn_restart_txg
!= 0 &&
1890 scn
->scn_restart_txg
<= tx
->tx_txg
);